Richard Rhodes.
Foreword to the
25th Anniversary Edition
More than seven decades aer its conception under the looming storm front
of the Second World War, the Manhattan Project is fading into mythe
massive production reactors and plutonium extraction canyons at Hanford,
Washington; the half-mile-long uranium enrichment factory at Oak Ridge,
Tennessee; the several hundred thousand workers who built and operated
the vast machinery while managing to keep its purpose secret, disappear
from view, leaving behind a bare nucleus of legend: a secret laboratory on a
New Mexican mesa, Los Alamos, where the actual bombs were designed and
built; a charismatic lab director, the American physicist Robert
Oppenheimer, who rose to international prominence postwar until his
enemies brought him low; a lone B-29 bomber incongruently named for the
pilot’s mother, Enola Gay; a devastated city, Hiroshima, and poor ruined
Nagasaki all but forgotten.
Almost mythical too are the weapons themselves, except when an enemy
seeks to acquire them.
New nuclear powers are a threat, we are warned; old
nuclear powers keep the peace.
A young scholar, Anne Harrington de
Santana, has discerned that nuclear weapons have acquired the status of
fetish objects; like the coin of the realm in relation to commodities, our
glittering warheads have become markers of national power: “Just as access
to wealth in the form of money determines an individual’s opportunities and
place in a social hierarchy, access to power in the form of nuclear weapons
determines a state’s opportunities and place in the international order.” at’s
why most industrial nations have considered acquiring nuclear weapons at
one time or another since 1945 even as none has dared to use them.
If the
bombs were ever actually used, the walls would come tumbling down.
e danger of use was one reason I decided in 1978 to write the history of
the development of the first atomic bombs.
(Another reason was the
declassification of the bulk of Manhattan Project records, which made it
possible to support the story with documents.) Nuclear war seemed more
imminent then than it does now.
In the late 1970s and early 1980s, when I
researched and wrote this book, the nuclear arms race between the United
States and the Soviet Union appeared to be accelerating.
I, and many others,
worried that accident, inadvertence, or misunderstanding would lead to
catastrophe.
e Soviets were at war in Afghanistan and appeared to President Jimmy
Carter to be thrusting down toward the Arabian Sea and the oilrich Middle
East—something Carter swore the United States would not allow even if it
meant nuclear war.
e Soviets were determined to enlarge their nuclear
arsenal to match ours—a decision they made in the aermath of the Cuban
Missile Crisis of 1962, when President John F.
Kennedy was able to back
them down by threatening nuclear war—and the closer they came to parity
the more belligerently the American right howled for blood.
Ronald Reagan,
elected president in 1980, proceeded to more than double the U.S.
defense
budget while coining such provocative characterizations of the other nuclear
superpower as “the evil empire” and “the focus of evil in the modern world.”
e Soviets shot down a Korean airliner that had wandered into their
airspace, killing all aboard.
A 1983 NATO field exercise, Able Archer, which
included a trial run-up to nuclear war in which heads of government
participated, very nearly scared the Soviet leadership under an ailing Yuri
Andropov into launching a nuclear first strike.
Disturbing as these events were, I found it hard to believe that a species as
clever and adaptable as ours would voluntarily destroy itself, even though it
had voluntarily manufactured the means to do so.
I wondered if, back at the
beginning, before the first bombs burned out those two Japanese cities and
fundamentally changed the nature of war, there had been alternative
pathways to the present, pathways different from those which we and the
Soviets had followed.
Why seventy thousand nuclear weapons between us
when only a few were more than enough to destroy each other?
Why a
primarily military confrontation across the Cold War when nuclear weapons
made direct military conflict between the superpowers suicidal?
Why, on the
other hand, despite all the rhetoric and posturing, had not one nuclear
weapon been exploded in anger since Nagasaki?
It seemed to me that if I
went back to the beginning, even to before the beginning, when releasing
the enormous energies held latent in the nuclei of atoms was simply an
interesting and challenging physics problem, that I might rediscover
abandoned pathways which could, if reilluminated, lead toward an outcome
different from the looming threat of nuclear apocalypse.
ose alternative pathways did exist.
I did find them, as others had before
me, hidden in plain sight.
By placing them at the center of this book I tried
to reilluminate them.
e Making of the Atomic Bomb has become the
standard prehistory and history of the Manhattan Project.
It has been
translated into a dozen languages and published around the world.
I’ve
heard from enough people in government, in the United States and abroad,
to know that it has been widely read in pentagons and white houses.
In that
way it has contributed to a general understanding of the paradox of nuclear
weapons.
I don’t mean the paradox of deterrence, which partakes of the
fetish object delusion that Harrington de Santana delineates.
I mean the
paradox which the great Danish physicist Niels Bohr first articulated: that,
though nuclear weapons are the property of individual nation-states, which
claim the right to hold and to use them in defense of national sovereignty, in
their indiscriminate destructiveness they are a common danger to all, like an
epidemic disease, and like an epidemic disease they transcend national
borders, disputes, and ideologies.
I included so much Manhattan Project prehistory in this book—the
history of nuclear physics from the discovery of radioactivity at the end of
the nineteenth century up to the discovery of nuclear fission in Nazi
Germany in late 1938—partly because I believed I had to understand the
physics, as well as a layman can, if I hoped to understand what was
revolutionary about the bombs, and assumed readers would wish to do so as
well.
I had one lecture course in physics in college, no more, but I learned
there that nuclear physics is almost entirely an experimental science.
Which
means that the discoveries that led to the bombs were the consequence of
the physical manipulation of objects in the laboratory: this metal box, fitted
with a radiation source, a sample inserted, measured using this instrument,
with this result, and so on.
Once I’d mastered the jargon, it was possible to
read through the classic papers in the field, visualize the experiments, and
understand the discoveries, at least where their application to making
bombs was concerned.
Later, I realized that reviewing the history of nuclear physics served
another purpose as well: It gave the lie to the naive belief that the physicists
could have come together when nuclear fission was discovered (in Nazi
Germany!) and agreed to keep the discovery a secret, thereby sparing
humankind the nuclear burden.
No.
Given the development of nuclear
physics up to 1938, development that physicists throughout the world
pursued in all innocence of any intention of finding the engine of a new
weapon of mass destruction—only one of them, the remarkable Hungarian
physicist Leo Szilard, took that possibility seriously—the discovery of
nuclear fission was inevitable.
To stop it, you would have had to stop physics.
If German scientists hadn’t made the discovery when they did, British,
French, American, Russian, Italian, or Danish scientists would have done so,
almost certainly within days or weeks.
ey were all working at the same
cutting edge, trying to understand the strange results of a simple experiment
bombarding uranium with neutrons.
Here was no Faustian bargain, as movie directors and other naifs still find
it intellectually challenging to imagine.
Here was no evil machinery that the
noble scientists might have hidden from the politicians and the generals.
To
the contrary, here was a new insight into how the world works, an energetic
reaction, older than the earth, that science had finally devised the
instruments and arrangements to coax forth.
“Make it seem inevitable,”
Louis Pasteur used to advise his students when they prepared to write up
their discoveries.
But it was.
To wish that it might have been ignored or
suppressed is barbarous.
“Knowledge,” Niels Bohr once noted, “is itself the
basis for civilization.” You cannot have the one without the other; the one
depends upon the other.
Nor can you have only benevolent knowledge; the
scientific method doesn’t filter for benevolence.
Knowledge has
consequences, not always intended, not always comfortable, not always
welcome.
e earth revolves around the sun, not the sun around the earth.
“It is a profound and necessary truth,” Robert Oppenheimer would say, “that
the deep things in science are not found because they are useful; they are
found because it was possible to find them.”
ose first atomic bombs, made by hand on a mesa in New Mexico, fell
onto a stunned pre-nuclear world.
Aerward, when the Soviet Union
exploded a copy of the Fat Man plutonium bomb built from plans supplied
by Klaus Fuchs and Ted Hall and then went on to develop a comprehensive
arsenal of its own, matching the American arsenal; when the hydrogen
bomb increased the already devastating destructiveness of nuclear weapons
by several orders of magnitude; when the British, the French, the Chinese,
the Israelis, and other nations acquired nuclear weapons, the strange new
nuclear world matured.
Bohr proposed once that the goal of science is not
universal truth.
Rather, he argued, the modest but relentless goal of science
is “the gradual removal of prejudices.” e discovery that the earth revolves
around the sun has gradually removed the prejudice that the earth is the
center of the universe.
e discovery of microbes is gradually removing the
prejudice that disease is a punishment from God.
e discovery of evolution
is gradually removing the prejudice that Homo sapiens is a separate and
special creation.
e closing days of the Second World War marked a similar turning point
in human history, the point of entry into a new era when humankind for the
first time acquired the means of its own destruction.
e discovery of how
to release nuclear energy, and its application to build weapons of mass
destruction, has gradually removed the prejudice on which total war is
based: the insupportable conviction that there is a limited amount of energy
available in the world to concentrate into explosives, that it is possible to
accumulate more of such energy than one’s enemies and thereby militarily to
prevail.
So cheap, so portable, so holocaustal did nuclear weapons eventually
become that even nation-states as belligerent as the Soviet Union and the
United States preferred to sacrifice a portion of their national sovereignty—
preferred to forego the power to make total war—rather than be destroyed
in their fury.
Lesser wars continue, and will continue until the world
community is sufficiently impressed with their destructive futility to forge
new instruments of protection and new forms of citizenship.
But world war
at least has been revealed to be historical, not universal, a manifestation of
destructive technologies of limited scale.
In the long history of human
slaughter that is no small achievement.
In the middle years of my life I lived on four acres of land in Connecticut,
a meadow completely enclosed within a forested wildlife preserve.
It teemed
with creatures: deer, squirrels, raccoons, a woodchuck family, turkeys,
songbirds, crows, a Cooper’s hawk, even a pair of coyotes.
Except for the
hawk, every one of those animals constantly and fearfully watched over its
shoulder lest it be caught, torn, and eaten alive.
From the animals’ point of
view, my edenic four acres were a war zone.
Only very rarely does an animal
living under natural conditions in the wild die of old age.
Until recently, the human world was not much different.
Since we are
predators, at the top of the food chain, our worst natural enemies
historically have been microbes.
Natural violence, in the form of epidemic
disease, took a large and continuous toll of human life, such that very few
human beings lived out their natural lifespans.
By contrast, man-made death
—death, that is, by war and war’s attendant privations—persisted at a low
and relatively constant level throughout human history, hardly
distinguishable in the noise of the natural toll.
e invention of public health in the nineteenth century, and the
application of technology to war in the nineteenth and twentieth centuries,
inverted that pattern in the industrialized world.
Natural violence—
epidemic disease—retreated before the preventive methodologies of public
health to low and controlled levels.
At the same time, man-made death
began rapidly and pathologically to increase, reaching horrendous peaks in
the twentieth century’s two world wars.
Man-made death accounted for not
fewer than 200 million human lives in that most violent of all centuries in
human history, a number that the Scottish writer Gil Elliot vividly
characterizes as a “nation of the dead.”
e epidemic of man-made death collapsed abruptly aer the Second
World War.
Losses dropped precipitously to levels characteristic of the
earlier interwar years.
Since then, chartered violence has smoldered along,
flaring in guerrilla conflicts and conventional wars on the nuclear periphery,
accounting for an average of about 1.5 million lives a year—a terrible
number, to be sure, but the average before 1945 was fully a million lives
higher; and the peak, in 1943, 15 million.
Man-made death became epidemic in the twentieth century because
increasingly efficient killing technologies made the extreme exercise of
national sovereignty pathological.
And it was evidently the discovery of how
to release nuclear energy and its application to nuclear weapons that
reduced the virulence of the pathogen.
In a profound and even a quantifiable
sense, the weapons that counseled caution these past seven decades at the
level of deep nuclear fear served as containers in which to sequester the
deaths they held potential, like a vaccine made from the attenuated
pathogen itself.
It required three tons of Allied bombs to kill a German
citizen during the Second World War.
By that quantitative measure, the
strategic arsenals of the United States and the Soviet Union at the height of
the Cold War held latent some three billion deaths, a number that
corresponds closely to a 1984 World Health Organization estimate, arrived
at by other means, of potential deaths from a full-scale nuclear war.
Packaging death in the form of nuclear weapons made it visible.
e
sobering arsenals became memento mori, blunt reminders of our collective
mortality.
In the confusion of the battlefield, in the air and on the high seas
it had been possible before to deny or ignore the terrible cost in lives that the
pursuit of absolute sovereignty entails.
Nuclear weapons, the ultimate
containers of man-made death, made the consequences of sovereign
violence starkly obvious for the first time in human history.
Since there was
no sure defense against such weapons, they also made the consequences
certain.
A new caste of arms strategists hustled to discover ways to use them,
but every strategy foundered on the certain calculus of escalation.
“Every
great and deep difficulty bears within itself its own solution,” Niels Bohr had
counseled the scientists at Los Alamos whose consciences he found stirred
when he arrived there in 1943.
Nuclear weapons, encapsulating potential
human violence at its most indiscriminate extreme, paradoxically
demonstrate the reductio ad absurdum of man-made death.
e years since
1945 have been a dangerous but unavoidable learning experience.
On many
more occasions than the Cuban Missile Crisis and the near-debacle of Able
Archer 83, I’ve been told, we almost lost our way.
We will confront such risk again, and may we be so lucky the next time,
and the next aer that.
Or perhaps the disaster will break in some other
hemisphere and the millions who will die will fall under another flag.
It
won’t take much to involve the rest of us even at a ten-thousandmile remove.
In 2008, some of the scientists who modeled the original 1983 nuclear
winter scenario investigated the likely result of a theoretical regional nuclear
war between India and Pakistan, a war they postulated to involve only 100
Hiroshima-scale nuclear weapons, yielding a total of only 1.5 megatons—no
more than the yield of some single warheads in the U.S.
and Russian
arsenals.
ey were shocked to discover that because such an exchange
would inevitably be targeted on cities filled with combustible materials, the
resulting firestorms would inject massive volumes of black smoke into the
upper atmosphere which would spread around the world, cooling the earth
long enough and sufficiently to produce worldwide agricultural collapse.
Twenty million prompt deaths from blast, fire, and radiation, Alan Robock
and Owen Brian Toon projected, and another billion deaths in the months
that followed from mass starvation—from a mere 1.5 -megaton regional
nuclear war.
e 1996 Canberra Commission on the Elimination of Nuclear Weapons
identified a fundamental principle that it called the “axiom of proliferation.”
In its most succinct form, the axiom of proliferation asserts that As long as
any state has nuclear weapons, others will seek to acquire them.
A member of
the commission, the Australian ambassador-at-large for nuclear
disarmament, Richard Butler, told me, “e basic reason for this assertion is
that justice, which most human beings interpret essentially as fairness, is
demonstrably a concept of the deepest importance to people all over the
world.
Relating this to the axiom of proliferation, it is manifestly the case
that the attempts over the years of those who own nuclear weapons to assert
that their security justifies having those nuclear weapons while the security
of others does not, has been an abject failure.”
Elaborating before an audience in Sydney in 2002, Butler said, “I have
worked on the Nuclear Non-Proliferation Treaty all my adult life....
e
problem of nuclear-weapon haves and have-nots is the central, perennial
one.” From 1997 to 1999 Butler was the last chairman of UNSCOM, the
United Nations commission monitoring the disarming of Iraq.
“Amongst my
toughest moments in Baghdad,” he said in Sydney, “were when the Iraqis
demanded that I explain why they should be hounded for their weapons of
mass destruction when, just down the road, Israel was not, even though it
was known to possess some 200 nuclear weapons.
I confess too,” Butler
continued, “that I flinch when I hear American, British, and French
fulminations against weapons of mass destruction, ignoring the fact that
they are the proud owners of massive quantities of those weapons,
unapologetically insisting that they are essential for their national security
and will remain so.”
“e principle I would derive from this,” Butler concluded, “is that
manifest unfairness, double standards, no matter what power would appear
at a given moment to support them, produces a situation that is deeply,
inherently, unstable.
is is because human beings will not swallow such
unfairness.
is principle is as certain as the basic laws of physics itself.”
At a later time and place Butler spoke of the particular resistance of
Americans to recognizing their double standard.
“My attempts to have the
Americans enter into discussions about double standards,” he said, “have
been an abject failure—even with highly educated and engaged people.
I
sometimes felt I was speaking to them in Martian, so deep is their inability
to understand.
What Americans totally fail to understand is that their
weapons of mass destruction are just as much a problem as are those of
Iraq.” Or of Iran, North Korea—or of any other confirmed or would-be
nuclear power.
e Canberra Commission was speaking directly to the original nuclear
powers, of course, the five nations whose status as nuclearweapons states
had been effectively grandfathered into the 1968 Nuclear Non-Proliferation
Treaty.
In 2009, in Prague, President Barack Obama offered a chilling
corollary to the axiom of proliferation.
“Some argue that the spread of these
weapons cannot be stopped, cannot be checked,” he said—“that we are
destined to live in a world where more nations and more people possess the
ultimate tools of destruction.
Such fatalism is a deadly adversary, for if we
believe that the spread of nuclear weapons is inevitable, then in some way we
are admitting to ourselves that the use of nuclear weapons is inevitable.”
And should we come to such disaster, would we still believe the weapons
keep us safe?
Would we see their possession then for what it is now, a crime
against humanity?
Would we wish we had done the hard work of abolishing
them, everywhere in the world?
I have studied and written about nuclear history now for more than thirty
years.
What I take away from this long venture, most of all, is a sense of awe
at the depth and power of the natural world, and a fascination with the
complexities and the ironies of our species’ continuing encounter with
technology.
Despite everything, across these past seven decades—nearly the
length of my life—we have managed to take into our clumsy hands a
limitless new source of energy, hold it, examine it, turn it over, he it, and
put it to work without yet blowing ourselves up.
When we finally make our
way across to the other shore—when all the nuclear weapons have been
dismantled and their cores blended down for reactor fuel—we will find
ourselves facing much the same political insecurities we face now.
e
bombs didn’t fix them and they won’t be fixed by putting the bombs away.
e world will be a more transparent place, to be sure, but information
technology is moving it in that direction anyway.
e difference, as Jonathan
Schell has pointed out, will be that the threat of rearming will serve for
deterrence rather than the threat of nuclear war.
I think of a world without nuclear weapons not as a utopian dream but
simply as a world where delivery times have been deliberately lengthened to
months or even years, with correspondingly longer periods interim during
which to resolve disputes short of war.
In such a world, if negotiations fail, if
conventional skirmishes fail, if both sides revert to arming themselves with
nuclear weapons again—then at worst we will only arrive once more at the
dangerous precipice where we all stand now.
e discovery of how to release nuclear energy, like all fundamental
scientific discoveries, changed the structure of human affairs—permanently.
How that happened is the story this book attempts to tell.
—Richard Rhodes
Half Moon Bay
February 2012
PART ONE
PROFOUND
AND
NECESSARY
TRUTH
It is a profound and necessary truth that the deep things in science are not found because they are useful; they are found because it was possible to find them.
Robert Oppenheimer
It is still an unending source of surprise for me to see how a few scribbles on a blackboard or on a sheet of paper could change the course of human affairs.
Stanislaw Ulam
1
Moonshine
In London, where Southampton Row passes Russell Square, across from the
British Museum in Bloomsbury, Leo Szilard waited irritably one gray
Depression morning for the stoplight to change.
A trace of rain had fallen
during the night; Tuesday, September 12, 1933, dawned cool, humid and
dull.1 Drizzling rain would begin again in early aernoon.
When Szilard
told the story later he never mentioned his destination that morning.
He
may have had none; he oen walked to think.
In any case another
destination intervened.
e stoplight changed to green.
Szilard stepped off
the curb.
As he crossed the street time cracked open before him and he saw
a way to the future, death into the world and all our woe, the shape of things
to come.
Leo Szilard, the Hungarian theoretical physicist, born of Jewish heritage in
Budapest on February 11, 1898, was thirty-five years old in 1933.
At five feet,
six inches he was not tall even for the day.
Nor was he yet the “short fat
man,” round-faced and potbellied, “his eyes shining with intelligence and
wit” and “as generous with his ideas as a Maori chief with his wives,” that the
French biologist Jacques Monod met in a later year.2 Midway between trim
youth and portly middle age, Szilard had thick, curly, dark hair and an
animated face with full lips, flat cheekbones and dark brown eyes.
In
photographs he still chose to look soulful.
He had reason.
His deepest
ambition, more profound even than his commitment to science, was
somehow to save the world.
e Shape of ings to Come was H.
G.
Wells’ new novel, just published,
reviewed with avuncular warmth in e Times on September 1.
“Mr.
Wells’
newest ‘dream of the future’ is its own brilliant justification,” e Times
praised, obscurely.
3, 4 e visionary English novelist was one among Szilard’s network of influential acquaintances, a network he assembled by plating his
articulate intelligence with the purest brass.
In 1928, in Berlin, where he was a Privatdozent at the University of Berlin
and a confidant and partner in practical invention of Albert Einstein, Szilard
had read Wells’ tract e Open Conspiracy.
5 e Open Conspiracy was to be a public collusion of science-minded industrialists and financiers to
establish a world republic.
us to save the world.
Szilard appropriated
Wells’ term and used it off and on for the rest of his life.
More to the point,
he traveled to London in 1929 to meet Wells and bid for the Central
European rights to his books.
6, 7 Given Szilard’s ambition he would certainly have discussed much more than publishing rights.
But the meeting
prompted no immediate further connection.
He had not yet encountered
the most appealing orphan among Wells’ Dickensian crowd of tales.
Szilard’s past prepared him for his revelation on Southampton Row.
He
was the son of a civil engineer.
His mother was loving and he was well
provided for.
“I knew languages because we had governesses at home, first in
order to learn German and second in order to learn French.” He was “sort of
a mascot” to classmates at his Gymnasium, the University of Budapest’s
famous Minta.
8 “When I was young,” he told an audience once, “I had two
great interests in life; one was physics and the other politics.
”9 He remembers
informing his awed classmates, at the beginning of the Great War, when he
was sixteen, how the fortunes of nations should go, based on his precocious
weighing of the belligerents’ relative political strength:
I said to them at the time that I did of course not know who would win the war, but I did know
how the war ought to end.
It ought to end by the defeat of the central powers, that is the Austro-
Hungarian monarchy and Germany, and also end by the defeat of Russia.
I said I couldn’t quite see
how this could happen, since they were fighting on opposite sides, but I said that this was really
what ought to happen.
In retrospect I find it difficult to understand how at the age of sixteen and
without any direct knowledge of countries other than Hungary, I was able to make this
statement.
10
He seems to have assembled his essential identity by sixteen.
He believed
his clarity of judgment peaked then, never to increase further; it “perhaps
even declined.” 11
His sixteenth year was the first year of a war that would shatter the
political and legal agreements of an age.
at coincidence—or catalyst—by
itself could turn a young man messianic.
To the end of his life he made dull
men uncomfortable and vain men mad.
He graduated from the Minta in 1916, taking the Eötvös Prize, the
Hungarian national prize in mathematics, and considered his further
education.12 He was interested in physics but “there was no career in physics
in Hungary.” 13 If he studied physics he could become at best a high school teacher.
He thought of studying chemistry, which might be useful later when
he picked up physics, but that wasn’t likely either to be a living.
He settled on
electrical engineering.
Economic justifications may not tell all.
A friend of
his studying in Berlin noticed as late as 1922 that Szilard, despite his Eötvös
Prize, “felt that his skill in mathematical operations could not compete with
that of his colleagues.” On the other hand, he was not alone among
Hungarians of future prominence in physics in avoiding the backwater
science taught in Hungarian universities at the time.
14
He began engineering studies in Budapest at the King Joseph Institute of
Technology, then was draed into the Austro-Hungarian Army.
Because he
had a Gymnasium education he was sent directly to officers’ school to train
for the cavalry.
A leave of absence almost certainly saved his life.
He asked
for leave ostensibly to give his parents moral support while his brother had a
serious operation.
15 In fact, he was ill.
He thought he had pneumonia.
He
wanted to be treated in Budapest, near his parents, rather than in a frontier
Army hospital.
He waited standing at attention for his commanding officer
to appear to hear his request while his fever burned at 102 degrees.
e
captain was reluctant; Szilard characteristically insisted on his leave and got
it, found friends to support him to the train, arrived in Vienna with a lower
temperature but a bad cough and reached Budapest and a decent hospital.
His illness was diagnosed as Spanish influenza, one of the first cases on the
Austro-Hungarian side.
e war was winding down.
Using “family
connections” he arranged some weeks later to be mustered out.16 “Not long
aerward, I heard that my own regiment,” sent to the front, “had been under
severe attack and that all of my comrades had disappeared.” 17
In the summer of 1919, when Lenin’s Hungarian protégé Bela Kun and his
Communist and Social Democratic followers established a shortlived Soviet
republic in Hungary in the disordered aermath of Austro-Hungarian
defeat, Szilard decided it was time to study abroad.
He was twenty-one years
old.
Just as he arranged for a passport, at the beginning of August, the Kun
regime collapsed; he managed another passport from the right-wing regime
of Admiral Nicholas Horthy that succeeded it and le Hungary around
Christmastime.18
Still reluctantly committed to engineering, Szilard enrolled in the
Technische Hochschule, the technology institute, in Berlin.
But what had
seemed necessary in Hungary seemed merely practical in Germany.
e
physics faculty of the University of Berlin included Nobel laureates Albert
Einstein, Max Planck and Max von Laue, theoreticians of the first rank.
Fritz
Haber, whose method for fixing nitrogen from the air to make nitrates for
gunpowder saved Germany from early defeat in the Great War, was only one
among many chemists and physicists of distinction at the several
government- and industry-sponsored Kaiser Wilhelm Institutes in the
elegant Berlin suburb of Dahlem.
e difference in scientific opportunity
between Budapest and Berlin le Szilard physically unable to listen to
engineering lectures.
“In the end, as always, the subconscious proved
stronger than the conscious and made it impossible for me to make any
progress in my studies of engineering.
Finally the ego gave in, and I le the
Technische Hochschule to complete my studies at the University, some time
around the middle of ‘21.” 19
Physics students at that time wandered Europe in search of exceptional
masters much as their forebears in scholarship and cra had done since
medieval days.
Universities in Germany were institutions of the state; a
professor was a salaried civil servant who also collected fees directly from
his students for the courses he chose to give (a Privatdozent, by contrast, was
a visiting scholar with teaching privileges who received no salary but might
collect fees).
If someone whose specialty you wished to learn taught at
Munich, you went to Munich; if at Göttingen, you went to Göttingen.
Science grew out of the cra tradition in any case; in the first third of the
twentieth century it retained—and to some extent still retains—an informal
system of mastery and apprenticeship over which was laid the more recent
system of the European graduate school.
is informal collegiality partly
explains the feeling among scientists of Szilard’s generation of membership
in an exclusive group, almost a guild, of international scope and values.
Szilard’s good friend and fellow Hungarian, the theoretical physicist
Eugene Wigner, who was studying chemical engineering at the Technische
Hochschule at the time of Szilard’s conversion, watched him take the
University of Berlin by storm.
“As soon as it became clear to Szilard that
physics was his real interest, he introduced himself, with characteristic
directness, to Albert Einstein.” Einstein was a man who lived apart—
preferring originality to repetition, he taught few courses—but Wigner
remembers that Szilard convinced him to give them a seminar on statistical
mechanics.
20, 21 Max Planck was a gaunt, bald elder statesman whose study of radiation emitted by a uniformly heated surface (such as the interior of a
kiln) had led him to discover a universal constant of nature.
He followed the
canny tradition among leading scientists of accepting only the most
promising students for tutelage; Szilard won his attention.
Max von Laue,
the handsome director of the university’s Institute for eoretical Physics,
who founded the science of X-ray crystallography and created a popular
sensation by thus making the atomic lattices of crystals visible for the first
time, accepted Szilard into his brilliant course in relativity theory and
eventually sponsored his Ph.22D.
dissertation.
23
e postwar German infection of despair, cynicism and rage at defeat ran
a course close to febrile hallucination in Berlin.
e university, centrally
located between Dorotheenstrasse and Unter den Linden due east of the
Brandenburg Gate, was well positioned to observe the bizarre effects.
Szilard
missed the November 1918 revolution that began among mutinous sailors at
Kiel, quickly spread to Berlin and led to the retreat of the Kaiser to Holland,
to armistice and eventually to the founding, aer bloody riots, of the
insecure Weimar Republic.
By the time he arrived in Berlin at the end of
1919 more than eight months of martial law had been lied, leaving a city at
first starving and bleak but soon restored to intoxicating life.
“ere was snow on the ground,” an Englishman recalls of his first look at
postwar Berlin in the middle of the night, “and the blend of snow, neon and
huge hulking buildings was unearthly.
You felt you had arrived somewhere
totally strange.” To a German involved in the Berlin theater of the 1920s “the
air was always bright, as if it were peppered, like New York late in autumn:
you needed little sleep and never seemed tired.
24 Nowhere else did you fail
in such good form, nowhere else could you be knocked on the chin time and
again without being counted out.” e German aristocracy retreated from
view, and intellectuals, film stars and journalists took its place; the major
annual social event in the city where an imperial palace stood empty was the
Press Ball, sponsored by the Berlin Press Club, which drew as many as six
thousand guests.
25, 26
Ludwig Mies van der Rohe designed his first glass-walled skyscraper in
postwar Berlin.27 Yehudi Menuhin made his precocious debut, with Einstein
in the audience to applaud him.
28 George Grosz sorted among his years of
savage observation on Berlin’s wide boulevards and published Ecce Homo.29
Vladimir Nabokov was there, observing “an elderly, rosy-faced beggar
woman with legs cut off at the pelvis...
set down like a bust at the foot of a
wall and...
selling paradoxical shoelaces.” Fyodor Vinberg, one of the Czar’s
departed officers, was there, publishing a shoddy newspaper, promoting e
Protocols of the Elders of Zion, which he had personally introduced into
Germany from Russia—a new German edition of that pseudo-
Machiavellian, patently fraudulent fantasy of world conquest sold more than
100,000 copies—and openly advocating the violent destruction of the
Jews.
30, 31 Hitler was not there until the end, because he was barred from northern Germany aer his release from prison in 1924, but he sent
rumpelstiltskin Joseph Goebbels to stand in for him; Goebbels learned to
break heads and spin propaganda in an open, lusty, jazz-drunk city he
slandered in his diary as “a dark and mysterious enigma.” 32
In the summer of 1922 the rate of exchange in Germany sank to 400
marks to the dollar.
It fell to 7,000 to the dollar at the beginning of January
1923, the truly terrible year.
One hundred sixty thousand in July.
One
million in August.
And 4.2 trillion marks to the dollar on November 23,
1923, when adjustment finally began.
Banks advertised for bookkeepers
good with zeros and paid out cash withdrawals by weight.
Antique stores
filled to the ceiling with the pawned treasures of the bankrupt middle class.
A theater seat sold for an egg.
Only those with hard currency—mostly
foreigners—thrived at a time when it was possible to cross Germany by first-
class railroad carriage for pennies, but they also earned the enmity of
starving Germans.
“No, one did not feel guilty,” the visiting Englishman
crows, “one felt it was perfectly normal, a gi from the gods.” 33
e German physicist Walter Elsasser, who later emigrated to the United
States, worked in Berlin in 1923 during an interlude in his student years; his
father had agreed to pay his personal expenses.
He was no foreigner, but
with foreign help he was able to live like one:
In order to make me independent of [inflation], my father had appealed to his friend, Kaufmann,
the banker from Basle, who had established for me an account in American dollars at a large
bank....
Once a week I took half a day off to go downtown by subway and withdrew my allowance
in marks; and it was more each time, of course.
Returning to my rented room, I at once bought
enough food staples to last the week, for within three days, all the prices would have risen
appreciably, by fieen percent, say, so that my allowance would have run short and would not have
permitted such pleasures as an excursion to Potsdam or to the lake country on Sundays....
I was
too young, much too callous, and too inexperienced to understand what this galloping inflation
must have meant—actual starvation and misery—to people who had to live on pensions or other
fixed incomes, or even to wage earners, especially those with children, whose pay lagged behind
the rate of inflation.34
So must Szilard have lived, except that no one recalls ever seeing him cook
for himself; he preferred the offerings of delicatessens and cafés.
He would
have understood what inflation meant and some of the reasons for its
extremity.
But though Szilard was preternaturally observant—“During a
long life among scientists,” writes Wigner, “I have met no one with more
imagination and originality, with more independence of thought and
opinion”—his recollections and his papers preserve almost nothing of these
Berlin days.
35 Germany’s premier city at the height of its postwar social,
political and intellectual upheaval earns exactly one sentence from Szilard:
“Berlin at that time lived in the heyday of physics.” at was how much
physics, giving extraordinary birth during the 1920s to its modern synthesis,
meant to him.
36
* * *
Four years of study usually preceded a German student’s thesis work.
en, with a professor’s approval, the student solved a problem of his own
conception or one his professor supplied.
“In order to be acceptable,” says
Szilard, it “had to be a piece of really original work.
”37 If the thesis found
favor, the student took an oral examination one aernoon and if he passed
he was duly awarded a doctorate.
Szilard had already given a year of his life to the Army and two years to
engineering.
He wasted no time advancing through physics.
In the summer
of 1921 he went to Max von Laue and asked for a thesis topic.
Von Laue
apparently decided to challenge Szilard—the challenge may have been
friendly or it may have been an attempt to put him in his place—and gave
him an obscure problem in relativity theory.
“I couldn’t make any headway
with it.
As a matter of fact, I was not even convinced that this was a problem
that could be solved.” 38 Szilard worked on it for six months, until the
Christmas season, “and I thought Christmastime is not a time to work, it is a
time to loaf, so I thought I would just think whatever comes to my mind.”
What he thought, in three weeks, was how to solve a baffling
inconsistency in thermodynamics, the branch of physics that concerns
relationships between heat and other forms of energy.
ere are two
thermodynamic theories, both highly successful at predicting heat
phenomena.
One, the phenomenological, is more abstract and generalized
(and therefore more useful); the other, the statistical, is based on an atomic
model and corresponds more closely to physical reality.
In particular, the
statistical theory depicts thermal equilibrium as a state of random motion of
atoms.
Einstein, for example, had demonstrated in important papers in 1905
that Brownian motion—the continuous, random motion of particles such as
pollen suspended in a liquid—was such a state.39 But the more useful
phenomenological theory treated thermal equilibrium as if it were static, a
state of no change.
at was the inconsistency.
Szilard went for long walks—Berlin would have been cold and gray, the
grayness sometimes relieved by days of brilliant sunshine—“and I saw
something in the middle of the walk; when I came home I wrote it down;
next morning I woke up with a new idea and I went for another walk; this
crystallized in my mind and in the evening I wrote it down.
”40 It was, he
thought, the most creative period of his life.
“Within three weeks I had
produced a manuscript of something which was really quite original.
But I
didn’t dare to take it to von Laue, because it was not what he had asked me
to do.”
He took it instead to Einstein aer a seminar, buttonholed him and said
he would like to tell him about something he had been doing.
“Well, what have you been doing?” Szilard remembers Einstein saying.41
Szilard reported his “quite original” idea.
“at’s impossible,” Einstein said.
“is is something that cannot be done.”
“Well, yes, but I did it.”
“How did you do it?”
Szilard began explaining.
“Five or ten minutes” later, he says, Einstein
understood.
Aer only a year of university physics, Szilard had worked out a
rigorous mathematical proof that the random motion of thermal
equilibrium could be fitted within the framework of the phenomenological
theory in its original, classical form, without reference to a limiting atomic
model—“and [Einstein] liked this very much.”
us emboldened, Szilard took his paper—its title would be “On the
extension of phenomenological thermodynamics to fluctuation
phenomena”—to von Laue, who received it quizzically and took it home.
“And next morning, early in the morning, the telephone rang.
It was von
Laue.
He said, ‘Your manuscript has been accepted as your thesis for the
Ph.D.
degree.’ ” 42
Six months later Szilard wrote another paper in thermodynamics, “On the
decrease of entropy in a thermodynamic system by the intervention of
intelligent beings,” that eventually would be recognized as one of the
important foundation documents of modern information theory.
43 By then
he had his advanced degree; he was Dr.
Leo Szilard now.
He experimented
with X-ray effects in crystals, von Laue’s field, at the Kaiser Wilhelm Institute
for Chemistry in Dahlem until 1925; that year the University of Berlin
accepted his entropy paper as his Habilitationsschri, his inaugural
dissertation, and he was thereupon appointed a Privatdozent, a position he
held until he le for England in 1933.44
One of Szilard’s sidelines, then and later, was invention.
Between 1924 and
1934 he applied to the German patent office individually or jointly with his
partner Albert Einstein for twenty-nine patents.
Most of the joint
applications dealt with home refrigeration.45 “A sad newspaper story...
caught the attention of Einstein and Szilard one morning,” writes one of
Szilard’s later American protégés: “It was reported in a Berlin newspaper
that an entire family, including a number of young children, had been found
asphyxiated in their apartment as a result of their inhalation of the noxious
fumes of the [chemical] that was used as the refrigerant in their primitive
refrigerator and that had escaped in the night through a leaky pump
valve.
”46 Whereupon the two physicists devised a method of pumping
metallicized refrigerant by electromagnetism, a method that required no
moving parts (and therefore no valve seals that might leak) except the
refrigerant itself.47 A.E.G., the German General Electric, signed Szilard on as
a paid consultant and actually built one of the Einstein-Szilard refrigerators,
but the magnetic pump was so noisy compared to even the noisy
conventional compressors of the day that it never le the engineering lab.
Another, oddly similar invention, also patented, might have won Szilard
world acclaim if he had taken it beyond the patent stage.
Independently of
the American experimental physicist Ernest O.
Lawrence and at least three
months earlier, Szilard worked out the basic principle and general design of
what came to be called, as Lawrence’s invention, the cyclotron, a device for
accelerating nuclear particles in a circular magnetic field, a sort of nuclear
pump.
Szilard applied for a patent on his device on January 5, 1929;
Lawrence first thought of the cyclotron on about April 1, 1929, producing a
small working model a year later—for which he won the 1939 Nobel Prize in
Physics.
48, 49
Szilard’s originality stopped at no waterline.
Somewhere along the way
from sixteen-year-old prophet of the fate of nations to thirty-one-year-old
open conspirer negotiating publishing rights with H.
G.
Wells, he conceived
an Open Conspiracy of his own.
He dated his social invention from “the
mid-twenties in Germany.” If so, then he went to see Wells in 1929 as much
from enthusiasm for the Englishman’s perspicacity as for his vision.50 C.
P.
Snow, the British physicist and novelist, writes of Leo Szilard that he “had a
temperament uncommon anywhere, maybe a little less uncommon among
major scientists.
51 He had a powerful ego and invulnerable egocentricity:
but he projected the force of that personality outward, with beneficent
intention toward his fellow creatures.
In that sense, he had a family
resemblance to Einstein on a reduced scale.” Beneficent intention in this
instance is a document proposing a new organization: Der Bund—the order,
the confederacy, or, more simply, the band.
52
e Bund, Szilard writes, would be “a closely knit group of people whose
inner bond is pervaded by a religious and scientific spirit”:53
If we possessed a magical spell with which to recognize the “best” individuals of the rising
generation at an early age...
then we would be able to train them to independent thinking, and
through education in close association we could create a spiritual leadership class with inner
cohesion which would renew itself on its own.
54
Members of this class would not be awarded wealth or personal glory.
To the
contrary, they would be required to take on exceptional responsibilities,
“burdens” that might “demonstrate their devotion.” It seemed to Szilard that
such a group stood a good chance of influencing public affairs even if it had
no formal structure or constitutional position.
But there was also the
possibility that it might “take over a more direct influence on public affairs
as part of the political system, next to government and parliament, or in the
place of government and parliament.
”55
“e Order,” Szilard wrote at a different time, “was not supposed to be
something like a political party...
but rather it was supposed to represent
the state.” 56 He saw representative democracy working itself out somehow
within the cells of thirty to forty people that would form the mature political
structure of the Bund.
“Because of the method of selection [and
education]...
there would be a good chance that decisions at the top level
would be reached by fair majorities.”
Szilard pursued one version or another of his Bund throughout his life.
It
appears as late as 1961, by then suitably disguised, in his popular story “e
Voice of the Dolphins”: a tankful of dolphins at a “Vienna Institute” begin to
impart their compelling wisdom to the world through their keepers and
interpreters, who are U.S.
and Russian scientists; the narrator slyly implies
that the keepers may be the real source of wisdom, exploiting mankind’s
fascination with superhuman saviors to save it.57
A wild burst of optimism—or opportunism—energized Szilard in 1930 to
organize a group of acquaintances, most of them young physicists, to begin
the work of banding together.
He was convinced in the mid-1920s that “the
parliamentary form of democracy would not have a very long life in
Germany” but he “thought that it might survive one or two generations.”
Within five years he understood otherwise.
58, 59 “I reached the conclusion something would go wrong in Germany...
in 1930.” Hjalmar Schacht, the
president of the German Reichsbank, meeting in Paris that year with a
committee of economists called to decide how much Germany could pay in
war reparations, announced that Germany could pay none at all unless its
former colonies, stripped from it aer the war, were returned.
“is was
such a striking statement to make that it caught my attention, and I
concluded that if Hjalmar Schacht believed he could get away with this,
things must be rather bad.
I was so impressed by this that I wrote a letter to
my bank and transferred every single penny I had out of Germany into
Switzerland.” 60
A far more organized Bund was advancing to power in Germany with
another and more primitive program to save the world.
at program, set
out arrogantly in an autobiographical book— Mein Kampf—would achieve a
lengthy and bloody trial.
Yet Szilard in the years ahead would lead a drive to
assemble a Bund of sorts; submerged from view, working to more urgent
and more immediate ends than utopia, that “closely knit group of people”
would finally influence world events more enormously even than Nazism.
* * *
Sometime during the 1920s, a new field of research caught Szilard’s
attention: nuclear physics, the study of the nucleus of the atom, where most
of its mass—and therefore its energy—is concentrated.
He was familiar with
the long record of outstanding work in the general field of radioactivity of
the German chemist Otto Hahn and the Austrian physicist Lise Meitner,
who made a productive team at the Kaiser Wilhelm Institute for Chemistry.
No doubt he was also alert as always to the peculiar tension in the air that
signaled the possibility of new developments.
e nuclei of some light atoms could be shattered by bombarding them
with atomic particles; that much the great British experimental physicist
Ernest Rutherford had already demonstrated.
Rutherford used one nucleus
to bombard another, but since both nuclei were strongly positively charged,
the bombarded nucleus repelled most attacks.
Physicists were therefore
looking for ways to accelerate particles to greater velocities, to force them
past the nucleus’ electrical barrier.
Szilard’s design of a cyclotron-like
particle accelerator that could serve such a purpose indicates that he was
thinking about nuclear physics as early as 1928.
Until 1932 he did no more than think.
He had other work and nuclear
physics was not yet sufficiently interesting to him.
It became compelling in
1932.
A discovery in physics opened the field to new possibilities while
discoveries Szilard made in literature and utopianism opened his mind to
new approaches to world salvation.
On February 27, 1932, in a letter to the British journal Nature, physicist
James Chadwick of the Cavendish Laboratory at Cambridge University,
Ernest Rutherford’s laboratory, announced the possible existence of a
neutron.
(He confirmed the neutron’s existence in a longer paper in the
Proceedings of the Royal Society four months later, but Szilard would no
more have doubted it at the time of Chadwick’s first cautious announcement
than did Chadwick himself; like many scientific discoveries, it was obvious
once it was demonstrated, and Szilard could repeat the demonstration in
Berlin if he chose.
61, 62) e neutron, a particle with nearly the same mass as the positively charged proton that until 1932 was the sole certain component
of the atomic nucleus, had no electric charge, which meant it could pass
through the surrounding electrical barrier and enter into the nucleus.
e
neutron would open the atomic nucleus to examination.
It might even be a
way to force the nucleus to give up some of its enormous energy.
Just then, in 1932, Szilard found or took up for the first time that
appealing orphan among H.
G.
Wells’ books that he had failed to discover
before: e World Set Free.
63 Despite its title, it was not a tract like e Open Conspiracy.
It was a prophetic novel, published in 1914, before the beginning
of the Great War.
irty years later Szilard could still summarize e World
Set Free in accurate detail.
Wells describes, he says:
...
the liberation of atomic energy on a large scale for industrial purposes, the development of
atomic bombs, and a world war which was apparently fought by an alliance of England, France,
and perhaps including America, against Germany and Austria, the powers located in the central
part of Europe.
He places this war in the year 1956, and in this war the major cities of the world are
all destroyed by atomic bombs.64
More personal discoveries emerged from Wells’ visionary novel—ideas
that anticipated or echoed Szilard’s utopian plans, responses that may have
guided him in the years ahead.
Wells writes that his scientist hero, for
example, was “oppressed, he was indeed scared, by his sense of the immense
consequences of his discovery.
He had a vague idea that night that he ought
not to publish his results, that they were premature, that some secret
association of wise men should take care of his work and hand it on from
generation to generation until the world was riper for its practical
application.
”65
Yet e World Set Free influenced Szilard less than its subject matter might
suggest.
“is book made a very great impression on me, but I didn’t regard
it as anything but fiction.
It didn’t start me thinking of whether or not such
things could in fact happen.
I had not been working in nuclear physics up to
that time.” 66
By his own account, a different and quieter dialogue changed the direction
of Szilard’s work.
e friend who had introduced him to H.
G.
Wells
returned in 1932 to the Continent:
I met him again in Berlin and there ensued a memorable conversation.
Otto Mandl said that now
he really thought he knew what it would take to save mankind from a series of ever-recurring wars
that could destroy it.
He said that Man has a heroic streak in himself.
Man is not satisfied with a
happy idyllic life: he has the need to fight and to encounter danger.
And he concluded that what
mankind must do to save itself is to launch an enterprise aimed at leaving the earth.
On this task
he thought the energies of mankind could be concentrated and the need for heroism could be
satisfied.
67 I remember very well my own reaction.
I told him that this was somewhat new to me, and that I really didn’t know whether I would agree with him.
e only thing I could say was this:
that if I came to the conclusion that this was what mankind needed, if I wanted to contribute
something to save mankind, then I would probably go into nuclear physics, because only through
the liberation of atomic energy could we obtain the means which would enable man not only to
leave the earth but to leave the solar system.
Such must have been Szilard’s conclusion; that year he moved to the
Harnack House of the Kaiser Wilhelm Institutes—a residence for visiting
scientists sponsored by German industry, a faculty club of sorts—and
approached Lise Meitner about the possibility of doing experimental work
with her in nuclear physics.
us to save mankind.68
He always lived out of suitcases, in rented rooms.
At the Harnack House
he kept the keys to his two suitcases at hand and the suitcases packed.
“All I
had to do was turn the key and leave when things got too bad.” ings got
bad enough to delay a decision about working with Meitner.
An older
Hungarian friend, Szilard remembers—Michael Polanyi, a chemist at the
Kaiser Wilhelm Institutes with a family to consider—viewed the German
political scene optimistically, like many others in Germany at the time.69 , 70
“ey all thought that civilized Germans would not stand for anything really
rough happening.” Szilard held no such sanguine view, noting that the
Germans themselves were paralyzed with cynicism, one of the uglier effects
on morals of losing a major war.
71
Adolf Hitler was appointed Chancellor of Germany on January 30, 1933.
On the night of February 27 a Nazi gang directed by the head of the Berlin
SA, Hitler’s private army, set fire to the imposing chambers of the Reichstag.
e building was totally destroyed.
Hitler blamed the arson on the
Communists and bullied a stunned Reichstag into awarding him emergency
powers.
Szilard found Polanyi still unconvinced aer the fire.
“He looked at
me and said, ‘Do you really mean to say that you think that [Minister] of the
Interior [Hermann Göring] had anything to do with this?’ and I said, ‘Yes,
this is precisely what I mean.’ He just looked at me with incredulous eyes.” In
late March, Jewish judges and lawyers in Prussia and Bavaria were dismissed
from practice.
72 On the weekend of April 1, Julius Streicher directed a
national boycott of Jewish businesses and Jews were beaten in the streets.
“I
took a train from Berlin to Vienna on a certain date, close to the first of
April, 1933,” Szilard writes.
“e train was empty.
e same train the next
day was overcrowded, was stopped at the frontier, the people had to get out,
and everybody was interrogated by the Nazis.73 is just goes to show that if
you want to succeed in this world you don’t have to be much cleverer than
other people, you just have to be one day earlier.”
e Law for the Restoration of the Career Civil Service was promulgated
throughout Germany on April 7 and thousands of Jewish scholars and
scientists lost their positions in German universities.
From England, where
he landed in early May, Szilard went furiously to work to help them emigrate
and to find jobs for them in England, the United States, Palestine, India,
China and points between.
If he couldn’t yet save all the world, he could at
least save some part of it.
He came up for air in September.
By then he was living at the Imperial
Hotel in Russell Square, having transferred £1,595 from Zurich to his bank
in London.74 More than half the money, £854, he held in trust for his
brother Béla; the rest would see him through the year.
75 Szilard’s funds came
from his patent licenses, refrigeration consulting and Privatdozent fees.
He
was busy finding jobs for others and couldn’t be bothered to seek one
himself.
He had few expenses in any case; a week’s lodging and three meals a
day at a good London hotel cost about £5.5 ; he was a bachelor most of his
life and his needs were simple.
“I was no longer thinking about this conversation [with Otto Mandl about
space travel], or about H.
G.
Wells’ book either, until I found myself in
London about the time of the British Association [meeting].
”76 Szilard’s
syntax slips here: the crucial word is until.
He had been too distracted by
events and by rescue work to think creatively about nuclear physics.
He had
even been considering going into biology, a radical change of field but one
that a number of able physicists have managed, in prewar days and since.
Such a change is highly significant psychologically and Szilard was to make
it in 1946.
But in September 1933, a meeting of the British Association for
the Advancement of Science, an annual assembly, intervened.
If on Friday, September 1, lounging in the lobby of the Imperial Hotel,
Szilard read e Times’ review of e Shape of ings to Come, then he
noticed the anonymous critic’s opinion that Wells had “attempted something
of the sort on earlier occasions—that rather haphazard work, e World Set
Free,’ comes particularly to mind—but never with anything like the same
continuous abundance and solidity of detail, or indeed, the power to
persuade as to the terrifying probability of some of the more immediate and
disastrous developments.” And may have thought again of the atomic bombs
of Wells’ earlier work, of Wells’ Open Conspiracy and his own, of Nazi
Germany and its able physicists, of ruined cities and general war.77
Without question Szilard read e Times of September 12, with its
provocative sequence of headlines:
THE BRITISH ASSOCIATION
BREAKING DOWN
THE ATOM
TRANSFORMATION OF
ELEMENTS
Ernest Rutherford, e Times reported, had recited a history of “the
discoveries of the last quarter of a century in atomic transmutation,”
including:
THE NEUTRON
NOVEL TRANSFORMATIONS
All of which made Szilard restive.
e leading scientists in Great Britain
were meeting and he wasn’t there.
He was safe, he had money in the bank,
but he was only another anonymous Jewish refugee down and out in
London, lingering over morning coffee in a hotel lobby, unemployed and
unknown.
en, midway along the second column of e Times’ summary of
Rutherford’s speech, he found:
HOPE OF TRANSFORMING ANY ATOM
What, Lord Rutherford asked in conclusion, were the prospects 20 or 30 years ahead?
78
High voltages of the order of millions of volts would probably be unnecessary as a means of
accelerating the bombarding particles.
Transformations might be effected with 30,000 or 70,000
volts....
He believed that we should be able to transform all the elements ultimately.
We might in these processes obtain very much more energy than the proton supplied, but on
the average we could not expect to obtain energy in this way.
It was a very poor and inefficient way
of producing energy, and anyone who looked for a source of power in the transformation of the
atoms was talking moonshine.
Did Szilard know what “moonshine” meant—“foolish or visionary talk”?
Did he have to ask the doorman as he threw down the newspaper and
stormed out into the street?
“Lord Rutherford was reported to have said that
whoever talks about the liberation of atomic energy on an industrial scale is
talking moonshine.
Pronouncements of experts to the effect that something
cannot be done have always irritated me.”
“is sort of set me pondering as I was walking in the streets of London,
and I remember that I stopped for a red light at the intersection of
Southampton Row....79 I was pondering whether Lord Rutherford might
not prove to be wrong.” 80
“It occurred to me that neutrons, in contrast to alpha particles, do not
ionize [i.e., interact electrically with] the substance through which they
pass.
81
“Consequently, neutrons need not stop until they hit a nucleus with which
they may react.”
Szilard was not the first to realize that the neutron might slip past the
positive electrical barrier of the nucleus; that realization had come to other
physicists as well.
But he was the first to imagine a mechanism whereby
more energy might be released in the neutron’s bombardment of the nucleus
than the neutron itself supplied.
ere was an analogous process in chemistry.
Polanyi had studied it.
82 A
comparatively small number of active particles—oxygen atoms, for example
—admitted into a chemically unstable system, worked like leaven to elicit a
chemical reaction at temperatures much lower than the temperature that the
reaction normally required.
Chain reaction, the process was called.
One
center of chemical reaction produces thousands of product molecules.
One
center occasionally has an especially favorable encounter with a reactant and
instead of forming only one new center, it forms two or more, each of which
is capable in turn of propagating a reaction chain.
Chemical chain reactions are self-limiting.
Were they not, they would run
away in geometric progression: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024,
2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144, 524288, 1048576,
2097152, 4194304, 8388608, 16777216, 33554432, 67108868, 134217736...
“As the light changed to green and I crossed the street,” Szilard recalls,
“it...
suddenly occurred to me that if we could find an element which is
split by neutrons and which would emit two neutrons when it absorbs one
neutron, such an element, if assembled in sufficiently large mass, could
sustain a nuclear chain reaction.
83, 84
“I didn’t see at the moment just how one would go about finding such an
element, or what experiments would be needed, but the idea never le me.
In certain circumstances it might be possible to set up a nuclear chain
reaction, liberate energy on an industrial scale, and construct atomic
bombs.”
Leo Szilard stepped up onto the sidewalk.
Behind him the light changed to
red.
2
Atoms and Void
Atomic energy requires an atom.
No such beast was born legitimately into
physics until the beginning of the twentieth century.
e atom as an idea—
as an invisible layer of eternal, elemental substance below the world of
appearances where things combine, teem, dissolve and rot—is ancient.
Leucippus, a Greek philosopher of the fih century B.C.
whose name survives
on the strength of an allusion in Aristotle, proposed the concept;
Democritus, a wealthy racian of the same era and wider repute, developed
it.
“ ‘For by convention color exists,’ ” the Greek physician Galen quotes
from one of Democritus’ seventy-two lost books, “ ‘by convention bitter, by
convention sweet, but in reality atoms and void.’ ” From the seventeenth
century onward, physicists postulated atomic models of the world whenever
developments in physical theory seemed to require them.
85 But whether or
not atoms really existed was a matter for continuing debate.
Gradually the debate shied to the question of what kind of atom was
necessary and possible.
Isaac Newton imagined something like a miniature
billiard ball to serve the purposes of his mechanical universe of masses in
motion: “It seems probable to me,” he wrote in 1704, “that God in the
beginning formed matter in solid, massy, hard, impenetrable, movable
particles, of such sizes and figures, and with such other properties, and in
such proportion to space, as most conduced to the end to which he formed
them.
”86 e Scottish physicist James Clerk Maxwell, who organized the
founding of the Cavendish Laboratory, published a seminal Treatise on
Electricity and Magnetism in 1873 that modified Newton’s purely mechanical
universe of particles colliding in a void by introducing into it the idea of an
electromagnetic field.
e field permeated the void; electric and magnetic
energy propagated through it at the speed of light; light itself, Clerk Maxwell
demonstrated, is a form of electromagnetic radiation.
But despite his
modifications, Clerk Maxwell was as devoted as Newton to a hard,
mechanical atom:
ough in the course of ages catastrophes have occurred and may yet occur in the heavens, though ancient systems may be dissolved and new systems evolved out of their ruins, the [atoms] out of
which [the sun and the planets] are built—the foundation stones of the material universe—remain
unbroken and unworn.
ey continue this day as they were created—perfect in number and
measure and weight.
87
Max Planck thought otherwise.
He doubted that atoms existed at all, as
did many of his colleagues—the particulate theory of matter was an English
invention more than a Continental, and its faintly Britannic odor made it
repulsive to the xenophobic German nose—but if atoms did exist he was
sure they could not be mechanical.
“It is of paramount importance,” he
confessed in his Scientific Autobiography, “that the outside world is
something independent from man, something absolute, and the quest for
laws which apply to this absolute appeared to me as the most sublime
scientific pursuit in life.” Of all the laws of physics, Planck believed that the
thermodynamic laws applied most basically to the independent “outside
world” that his need for an absolute required.
88 He saw early that purely
mechanical atoms violated the second law of thermodynamics.
His choice
was clear.
e second law specifies that heat will not pass spontaneously from a
colder to a hotter body without some change in the system.
Or, as Planck
himself generalized it in his Ph.D.
dissertation at the University of Munich
in 1879, that “the process of heat conduction cannot be completely reversed
by any means.” Besides forbidding the construction of perpetual-motion
machines, the second law defines what Planck’s predecessor Rudolf Clausius
named entropy: because energy dissipates as heat whenever work is done—
heat that cannot be collected back into useful, organized form—the universe
must slowly run down to randomness.89 is vision of increasing disorder
means that the universe is one-way and not reversible; the second law is the
expression in physical form of what we call time.
But the equations of
mechanical physics—of what is now called classical physics—theoretically
allowed the universe to run equally well forward or backward.
“us,” an
important German chemist complained, “in a purely mechanical world, the
tree could become a shoot and a seed again, the butterfly turn back into a
caterpillar, and the old man into a child.
No explanation is given by the
mechanistic doctrine for the fact that this does not happen....
e actual
irreversibility of natural phenomena thus proves the existence of
phenomena that cannot be described by mechanical equations; and with this
the verdict on scientific materialism is settled.” 90 Planck, writing a few years
earlier, was characteristically more succinct: “e consistent implementation
of the second law...
is incompatible with the assumption of finite atoms.
”91
A major part of the problem was that atoms were not then directly
accessible to experiment.
ey were a useful concept in chemistry, where
they were invoked to explain why certain substances—elements—combine
to make other substances but cannot themselves be chemically broken
down.
Atoms seemed to be the reason gases behaved as they did, expanding
to fill whatever container they were let into and pushing equally on all the
container’s walls.
ey were invoked again to explain the surprising
discovery that every element, heated in a laboratory flame or vaporized in an
electric arc, colors the resulting light and that such light, spread out into its
rainbow spectrum by a prism or a diffraction grating, invariably is divided
into bands by characteristic bright lines.
But as late as 1894, when Robert
Cecil, the third Marquis of Salisbury, chancellor of Oxford and former
Prime Minister of England, catalogued the unfinished business of science in
his presidential address to the British Association, whether atoms were real
or only convenient and what structure they hid were still undecided issues:
What the atom of each element is, whether it is a movement, or a thing, or a vortex, or a point
having inertia, whether there is any limit to its divisibility, and, if so, how that limit is imposed,
whether the long list of elements is final, or whether any of them have any common origin, all these questions remain surrounded by a darkness as profound as ever.92
Physics worked that way, sorting among alternatives: all science works that
way.
e chemist Michael Polanyi, Leo Szilard’s friend, looked into the
workings of science in his later years at the University of Manchester and at
Oxford.
He discovered a traditional organization far different from what
most nonscientists suppose.
A “republic of science,” he called it, a
community of independent men and women freely cooperating, “a highly
simplified example of a free society.” Not all philosophers of science, which
is what Polanyi became, have agreed.93 , 94 Even Polanyi sometimes called science an “orthodoxy.” But his republican model of science is powerful in
the same way successful scientific models are powerful: it explains
relationships that have not been clear.
Polanyi asked straightforward questions.
How were scientists chosen?
What oath of allegiance did they swear?
Who guided their research—chose
the problems to be studied, approved the experiments, judged the value of
the results?
In the last analysis, who decided what was scientifically “true”?
Armed with these questions, Polanyi then stepped back and looked at
science from outside.
Behind the great structure that in only three centuries had begun to
reshape the entire human world lay a basic commitment to a naturalistic
view of life.
Other views of life dominated at other times and places—the
magical, the mythological.
Children learned the naturalistic outlook when
they learned to speak, when they learned to read, when they went to school.
“Millions are spent annually on the cultivation and dissemination of science
by the public authorities,” Polanyi wrote once when he felt impatient with
those who refused to understand his point, “who will not give a penny for
the advancement of astrology or sorcery.
In other words, our civilization is
deeply committed to certain beliefs about the nature of things; beliefs which
are different, for example, from those to which the early Egyptian or the
Aztec civilizations were committed.
”95
Most young people learned no more than the orthodoxy of science.
ey
acquired “the established doctrine, the dead letter.” Some, at university, went
on to study the beginnings of method.
96 ey practiced experimental proof
in routine research.
ey discovered science’s “uncertainties and its eternally
provisional nature.” at began to bring it to life.
97
Which was not yet to become a scientist.
To become a scientist, Polanyi
thought, required “a full initiation.” Such an initiation came from “close
personal association with the intimate views and practice of a distinguished
master.” e practice of science was not itself a science; it was an art, to be
passed from master to apprentice as the art of painting is passed or as the
skills and traditions of the law or of medicine are passed.
98, 99 You could not learn the law from books and classes alone.
You could not learn medicine.
No more could you learn science, because nothing in science ever quite fits;
no experiment is ever final proof; everything is simplified and approximate.
e American theoretical physicist Richard Feynman once spoke about
his science with similar candor to a lecture hall crowded with
undergraduates at the California Institute of Technology.
“What do we mean
by ‘understanding’ something?” Feynman asked innocently.
100 His amused
sense of human limitation informs his answer:
We can imagine that this complicated array of moving things which constitutes “the world” is
something like a great chess game being played by the gods, and we are observers of the game.
We
do not know what the rules of the game are; all we are allowed to do is to watch the playing.
Of
course, if we watch long enough, we may eventually catch on to a few of the rules.
e rules of the
game are what we mean by fundamental physics.
Even if we know every rule, however...
what we really can explain in terms of those rules is very limited, because almost all situations are so enormously complicated that we cannot follow the plays of the game using the rules, much less tell
what is going to happen next.
We must, therefore, limit ourselves to the more basic question of the
rules of the game.
If we know the rules, we consider that we “understand” the world.
Learning the feel of proof; learning judgment; learning which hunches to
play; learning which stunning calculations to rework, which experimental
results not to trust: these skills admitted you to the spectators’ benches at the
chess game of the gods, and acquiring them required sitting first at the feet
of a master.
Polanyi found one other necessary requirement for full initiation into
science: belief.
If science has become the orthodoxy of the West, individuals
are nevertheless still free to take it or leave it, in whole or in part; believers in
astrology, Marxism and virgin birth abound.
But “no one can become a
scientist unless he presumes that the scientific doctrine and method are
fundamentally sound and that their ultimate premises can be
unquestioningly accepted.” 101
Becoming a scientist is necessarily an act of profound commitment to the
scientific system and the scientific world view.
“Any account of science
which does not explicitly describe it as something we believe in is essentially
incomplete and a false pretense.
It amounts to a claim that science is
essentially different from and superior to all human beliefs that are not
scientific statements—and this is untrue.” Belief is the oath of allegiance that
scientists swear.
102
at was how scientists were chosen and admitted to the order.
ey
constituted a republic of educated believers taught through a chain of
masters and apprentices to judge carefully the slippery edges of their work.
Who then guided that work?
e question was really two questions: who
decided which problems to study, which experiments to perform?
And who
judged the value of the results?
Polanyi proposed an analogy.
Imagine, he said, a group of workers faced
with the problem of assembling a very large, very complex jigsaw puzzle.103
How could they organize themselves to do the job most efficiently?
Each worker could take some of the pieces from the pile and try to fit
them together.
at would be an efficient method if assembling a puzzle was
like shelling peas.
But it wasn’t.
e pieces weren’t isolated.
ey fitted
together into a whole.
And the chance of any one worker’s collection of
pieces fitting together was small.
Even if the group made enough copies of
the pieces to give every worker the entire puzzle to attack, no one would
accomplish as much alone as the group might if it could contrive a way to
work together.
e best way to do the job, Polanyi argued, was to allow each worker to
keep track of what every other worker was doing.
“Let them work on putting
the puzzle together in the sight of the others, so that every time a piece of it
is fitted in by one [worker], all the others will immediately watch out for the
next step that becomes possible in consequence.” at way, even though
each worker acts on his own initiative, he acts to further the entire group’s
achievement.
104 e group works independently together; the puzzle is
assembled in the most efficient way.
Polanyi thought science reached into the unknown along a series of what
he called “growing points,” each point the place where the most productive
discoveries were being made.105 Alerted by their network of scientific
publications and professional friendships—by the complete openness of
their communication, an absolute and vital freedom of speech—scientists
rushed to work at just those points where their particular talents would
bring them the maximum emotional and intellectual return on their
investment of effort and thought.
It was clear, then, who among scientists judged the value of scientific
results: every member of the group, as in a Quaker meeting.
“e authority
of scientific opinion remains essentially mutual; it is established between
scientists, not above them.” ere were leading scientists, scientists who
worked with unusual fertility at the growing points of their fields; but
science had no ultimate leaders.
106 Consensus ruled.
Not that every scientist was competent to judge every contribution.
e
network solved that problem too.
Suppose Scientist M announces a new
result.
He knows his highly specialized subject better than anyone in the
world; who is competent to judge him?
But next to Scientist M are Scientists
L and N.
eir subjects overlap M’s, so they understand his work well
enough to assess its quality and reliability and to understand where it fits
into science.
Next to L and N are other scientists, K and O and J and P, who
know L and N well enough to decide whether to trust their judgment about
M.
On out to Scientists A and Z, whose subjects are almost completely
removed from M’s.
“is network is the seat of scientific opinion,” Polanyi emphasized; “of an
opinion which is not held by any single human brain, but which, split into
thousands of different fragments, is held by a multitude of individuals, each
of whom endorses the other’s opinion at second hand, by relying on the
consensual chains which link him to all the others through a sequence of
overlapping neighborhoods.” 107 Science, Polanyi was hinting, worked like a
giant brain of individual intelligences linked together.
at was the source of
its cumulative and seemingly inexorable power.
But the price of that power,
as both Polanyi and Feynman are careful to emphasize, is voluntary
limitation.
Science succeeds in the difficult task of sustaining a political
network among men and women of differing backgrounds and differing
values, and in the even more difficult task of discovering the rules of the
chess game of the gods, by severely limiting its range of competence.
“Physics,” as Eugene Wigner once reminded a group of his fellows, “does not
even try to give us complete information about the events around us—it
gives information about the correlations between those events.
”108
Which still le the question of what standards scientists consulted when
they passed judgment on the contributions of their peers.
Good science,
original work, always went beyond the body of received opinion, always
represented a dissent from orthodoxy.
How, then, could the orthodox fairly
assess it?
Polanyi suspected that science’s system of masters and apprentices
protected it from rigidity.
e apprentice learned high standards of
judgment from his master.
At the same time he learned to trust his own
judgment: he learned the possibility and the necessity of dissent.
Books and
lectures might teach rules; masters taught controlled rebellion, if only by the
example of their own original—and in that sense rebellious—work.
Apprentices learned three broad criteria of scientific judgment.109 e first
criterion was plausibility.
at would eliminate crackpots and frauds.
It
might also (and sometimes did) eliminate ideas so original that the
orthodox could not recognize them, but to work at all, science had to take
that risk.
e second criterion was scientific value, a composite consisting of
equal parts accuracy, importance to the entire system of whatever branch of
science the idea belonged to, and intrinsic interest.
e third criterion was
originality.
Patent examiners assess an invention for originality according to
the degree of surprise the invention produces in specialists familiar with the
art.
Scientists judged new theories and new discoveries similarly.
Plausibility
and scientific value measured an idea’s quality by the standards of
orthodoxy; originality measured the quality of its dissent.
Polanyi’s model of an open republic of science where each scientist judges
the work of his peers against mutually agreed upon and mutually supported
standards explains why the atom found such precarious lodging in
nineteenth-century physics.
It was plausible; it had considerable scientific
value, especially in systematic importance; but no one had yet made any
surprising discoveries about it.
None, at least, sufficient to convince the
network of only about one thousand men and women throughout the world
in 1895 who called themselves physicists and the larger, associated network
of chemists.110
e atom’s time was at hand.
e great surprises in basic science in the
nineteenth century came in chemistry.
e great surprises in basic science in
the first half of the twentieth century would come in physics.
* * *
In 1895, when young Ernest Rutherford roared up out of the Antipodes to
study physics at the Cavendish with a view to making his name, the New
Zealand he le behind was still a rough frontier.
British nonconformist
crasmen and farmers and a few adventurous gentry had settled the rugged
volcanic archipelago in the 1840s, pushing aside the Polynesian Maori who
had found it first five centuries before; the Maori gave up serious resistance
aer decades of bloody skirmish only in 1871, the year Rutherford was born.
He attended recently established schools, drove the cows home for milking,
rode horseback into the bush to shoot wild pigeons from the berry-laden
branches of virgin miro trees, helped at his father’s flax mill at Brightwater
where wild flax cut from aboriginal swamps was retted, scutched and
hackled for linen thread and tow.
He lost two younger brothers to drowning;
the family searched the Pacific shore near the farm for months.
It was a hard and healthy childhood.
Rutherford capped it by winning
scholarships, first to modest Nelson College in nearby Nelson, South Island,
then to the University of New Zealand, where he earned an M.A.
with
double firsts in mathematics and physical science at twenty-two.
He was
sturdy, enthusiastic and smart, qualities he would need to carry him from
rural New Zealand to the leadership of British science.
Another, more subtle
quality, a braiding of country-boy acuity with a profound frontier
innocence, was crucial to his unmatched lifetime record of physical
discovery.
As his protégé James Chadwick said, Rutherford’s ultimate
distinction was “his genius to be astonished.” He preserved that quality
against every assault of success and despite a well-hidden but sometimes
sickening insecurity, the stiff scar of his colonial birth.
111, 112
His genius found its first occasion at the University of New Zealand,
where Rutherford in 1893 stayed on to earn a B.Sc.
Heinrich Hertz’s 1887
discovery of “electric waves”—radio, we call the phenomenon now—had
impressed Rutherford wonderfully, as it did young people everywhere in the
world.
To study the waves he set up a Hertzian oscillator—electrically
charged metal knobs spaced to make sparks jump between metal plates—in
a dank basement cloakroom.
He was looking for a problem for his first
independent work of research.
He located it in a general agreement among scientists, pointedly including
Hertz himself, that high-frequency alternating current, the sort of current a
Hertzian oscillator produced when the spark radiation surged rapidly back
and forth between the metal plates, would not magnetize iron.
Rutherford
suspected otherwise and ingeniously proved he was right.
e work earned
him an 1851 Exhibition scholarship to Cambridge.
He was spading up
potatoes in the family garden when the cable came.
His mother called the
news down the row; he laughed and jettisoned his spade, shouting triumph
for son and mother both: “at’s the last potato I’ll dig!” (irty-six years
later, when he was created Baron Rutherford of Nelson, he sent his mother a
cable in her turn: “Now Lord Rutherford, more your honour than mine.
”113,
114)“Magnetization of iron by high-frequency discharges” was skilled
observation and brave dissent.115 With deeper originality, Rutherford
noticed a subtle converse reaction while magnetizing iron needles with
high-frequency current: needles already saturated with magnetism became
partly demagnetized when a high-frequency current passed by.
His genius to
be astonished was at work.
He quickly realized that he could use radio
waves, picked up by a suitable antenna and fed into a coil of wire, to induce a
high-frequency current into a packet of magnetized needles.
en the
needles would be partly demagnetized and if he set a compass beside them it
would swing to show the change.
By the time he arrived on borrowed funds at Cambridge in September
1895 to take up work at the Cavendish under its renowned director, J.
J.
omson, Rutherford had elaborated his observation into a device for
detecting radio waves at a distance—in effect, the first crude radio receiver.
Guglielmo Marconi was still laboring to perfect his version of a receiver at
his father’s estate in Italy; for a few months the young New Zealander held
the world record in detecting radio transmissions at a distance.116
Rutherford’s experiments delighted the distinguished British scientists
who learned of them from J.
J.
omson.
ey quickly adopted Rutherford,
even seating him one evening at the Fellows’ high table at King’s in the place
of honor next to the provost, which made him feel, he said, “like an ass in a
lion’s skin” and which shaded certain snobs on the Cavendish staff green
with envy.
117 omson generously arranged for a nervous but exultant
Rutherford to read his third scientific paper, “A magnetic detector of
electrical waves and some of its applications,” at the June 18, 1896, meeting
of the Royal Society of London, the foremost scientific organization in the
world.
118 Marconi only caught up with him in September.119
Rutherford was poor.
He was engaged to Mary Newton, the daughter of
his University of New Zealand landlady, but the couple had postponed
marriage until his fortunes improved.
Working to improve them, he wrote
his fiancée in the midst of his midwinter research: “e reason I am so keen
on the subject [of radio detection] is because of its practical importance....
If my next week’s experiments come out as well as I anticipate, I see a chance
of making cash rapidly in the future.” 120
ere is mystery here, mystery that carries forward all the way to
“moonshine.” Rutherford was known in later years as a hard man with a
research budget, unwilling to accept grants from industry or private donors,
unwilling even to ask, convinced that string and sealing wax would carry the
day.
He was actively hostile to the commercialization of scientific research,
telling his Russian protégé Peter Kapitza, for example, when Kapitza was
offered consulting work in industry, “You cannot serve God and Mammon
at the same time.” 121 e mystery bears on what C.
P.
Snow, who knew him,
calls the “one curious exception” to Rutherford’s “infallible” intuition, adding
that “no scientist has made fewer mistakes.” e exception was Rutherford’s
refusal to admit the possibility of usable energy from the atom, the very
refusal that irritated Leo Szilard in 1933.122 “I believe that he was fearful that
his beloved nuclear domain was about to be invaded by infidels who wished
to blow it to pieces by exploiting it commercially,” another protege, Mark
Oliphant, speculates.
123 Yet Rutherford himself was eager to exploit radio
commercially in January 1896.
Whence the dramatic and lifelong change?
e record is ambiguous but suggestive.
e English scientific tradition
was historically genteel.
It generally disdained research patents and any
other legal and commercial restraints that threatened the open
dissemination of scientific results.
In practice that guard of scientific liberty
could molder into clubbish distaste for “vulgar commercialism.” Ernest
Marsden, a Rutherford-trained physicist and an insightful biographer, heard
that “in his early days at Cambridge there were some few who said that
Rutherford was not a cultured man.” One component of that canard may
have been contempt for his eagerness to make a profit from radio.124
It seems that J.
J.
omson intervened.
A grand new work had abruptly
offered itself.
On November 8, 1895, one month aer Rutherford arrived at
Cambridge, the German physicist Wilhelm Röntgen discovered X rays
radiating from the fluorescing glass wall of a cathode-ray tube.
Röntgen
reported his discovery in December and stunned the world.
e strange
radiation was a new growing point for science and omson began studying
it almost immediately.
At the same time he also continued his experiments
with cathode rays, experiments that would culminate in 1897 in his
identification of what he called the “negative corpuscle”—the electron, the
first atomic particle to be identified.
He must have needed help.
He would
also have understood the extraordinary opportunity for original research
that radiation offered a young man of Rutherford’s skill at experiment.
To settle the issue omson wrote the grand old man of British science,
Lord Kelvin, then seventy-two, asking his opinion of the commercial
possibilities of radio—“before tempting Rutherford to turn to the new
subject,” Marsden says.
Kelvin aer all, vulgar commercialism or not, had
developed the transoceanic telegraph cable.
“e reply of the great man was
that [radio] might justify a captial expenditure of a £100,000 Company on
its promotion, but no more.
”125
By April 24 Rutherford has seen the light.
He writes Mary Newton: “I
hope to make both ends meet somehow, but I must expect to dub out my
first year....
My scientific work at present is progressing slowly.
I am
working with the Professor this term on Röntgen Rays.
I am a little full up of
my old subject and am glad of a change.
I expect it will be a good thing for
me to work with the Professor for a time.
I have done one research to show I
can work by myself.
”126 e tone is chastened and not nearly convinced, as if
a ghostly, parental J.
J.
omson were speaking through Rutherford to his
fiancée.
He has not yet appeared before the Royal Society, where he was
hardly “a little full up” of his subject.
But the turnabout is accomplished.
Hereaer Rutherford’s healthy ambition will go to scientific honors, not
commercial success.
It seems probable that J.
J.
omson sat eager young Ernest Rutherford
down in the darkly paneled rooms of the Gothic Revival Cavendish
Laboratory that Clerk Maxwell had founded, at the university where Newton
wrote his great Principia, and kindly told him he could not serve God and
Mammon at the same time.
It seems probable that the news that the
distinguished director of the Cavendish had written the Olympian Lord
Kelvin about the commercial ambitions of a brash New Zealander chagrined
Rutherford to the bone and that he went away from the encounter feeling
grotesquely like a parvenu.
He would never make the same mistake again,
even if it meant strapping his laboratories for funds, even if it meant driving
away the best of his protégés, as eventually it did.
Even if it meant that
energy from his cherished atom could be nothing more than moonshine.
But if Rutherford gave up commercial wealth for holy science, he won the
atom in exchange.
He found its constituent parts and named them.
With
string and sealing wax he made the atom real.
* * *
e sealing wax was blood red and it was the Bank of England’s most visible
contribution to science.
British experimenters used Bank of England sealing
wax to make glass tubes airtight.127 Rutherford’s earliest work on the atom, like J.
J.
omson’s work with cathode rays, grew out of nineteenthcentury
examination of the fascinating effects produced by evacuating the air from a
glass tube that had metal plates sealed into its ends and then connecting the
metal plates to a battery or an induction coil.
us charged with electricity,
the emptiness inside the sealed tube glowed.
e glow emerged from the
negative plate—the cathode—and disappeared into the positive plate—the
anode.
If you made the anode into a cylinder and sealed the cylinder into
the middle of the tube you could project a beam of glow—of cathode rays—
through the cylinder and on into the end of the tube opposite the cathode.
If
the beam was energetic enough to hit the glass it would make the glass
fluoresce.
e cathode-ray tube, suitably modified, its all-glass end flattened
and covered with phosphors to increase the fluorescence, is the television
tube of today.
In the spring of 1897 omson demonstrated that the beam of glowing
matter in a cathode-ray tube was not made up of light waves, as (he wrote
drily) “the almost unanimous opinion of German physicists” held.
Rather,
cathode rays were negatively charged particles boiling off the negative
cathode and attracted to the positive anode.
ese particles could be
deflected by an electric field and bent into curved paths by a magnetic field.
ey were much lighter than hydrogen atoms and were identical “whatever
the gas through which the discharge passes” if gas was introduced into the
tube.128 Since they were lighter than the lightest known kind of matter and
identical regardless of the kind of matter they were born from, it followed
that they must be some basic constituent part of matter, and if they were a
part, then there must be a whole.
e real, physical electron implied a real,
physical atom: the particulate theory of matter was therefore justified for the
first time convincingly by physical experiment.
ey sang J.
J.’s success at the
annual Cavendish dinner:
e corpuscle won the day129
And in freedom went away
And became a cathode ray.
Armed with the electron, and knowing from other experiments that what
was le when electrons were stripped away from an atom was a much more
massive remainder that was positively charged, omson went on in the
next decade to develop a model of the atom that came to be called the “plum
pudding” model.
e omson atom, “a number of negativelyelectrified
corpuscles enclosed in a sphere of uniform positive electrification” like
raisins in a pudding, was a hybrid: particulate electrons and diffuse
remainder.
130 It served the useful purpose of demonstrating mathematically
that electrons could be arranged in stable configurations within an atom and
that the mathematically stable arrangements could account for the
similarities and regularities among chemical elements that the periodic table
of the elements displays.
It was becoming clear that electrons were
responsible for chemical affinities between elements, that chemistry was
ultimately electrical.
omson just missed discovering X rays in 1894.
He was not so unlucky
in legend as the Oxford physicist Frederick Smith, who found that
photographic plates kept near a cathode-ray tube were liable to be fogged
and merely told his assistant to move them to another place.131 , 132 omson noticed that glass tubing held “at a distance of some feet from the
dischargetube” fluoresced just as the wall of the tube itself did when
bombarded with cathode rays, but he was too intent on studying the rays
themselves to pursue the cause.133 Röntgen isolated the effect by covering
his cathode-ray tube with black paper.
When a nearby screen of fluorescent
material still glowed he realized that whatever was causing the screen to
glow was passing through the paper and the intervening air.
134 If he held his
hand between the covered tube and the screen, his hand slightly reduced the
glow on the screen but in dark shadow he could see its bones.
Röntgen’s discovery intrigued other researchers besides J.
J.
omson and
Ernest Rutherford.
e Frenchman Henri Becquerel was a third-generation
physicist who, like his father and grandfather before him, occupied the chair
of physics at the Musée d’Histoire Naturelle in Paris; like them also he was
an expert on phosphorescence and fluorescence—in his case, particularly of
uranium.
He heard a report of Röntgen’s work at the weekly meeting of the
Académie des Sciences on January 20, 1896.
He learned that the X rays
emerged from the fluorescing glass, which immediately suggested to him
that he should test various fluorescing materials to see if they also emitted X
rays.
He worked for ten days without success, read an article on X rays on
January 30 that encouraged him to keep working and decided to try a
uranium salt, uranyl potassium sulfate.
His first experiment succeeded—he found that the uranium salt emitted
radiation—but misled him.
He had sealed a photographic plate in black
paper, sprinkled a layer of the uranium salt onto the paper and “exposed the
whole thing to the sun for several hours.” When he developed the
photographic plate “I saw the silhouette of the phosphorescent substance in
black on the negative.” He mistakenly thought sunlight activated the effect,
much as cathode rays released Röntgen’s X rays from the glass.
135
e story of Becquerel’s subsequent serendipity is famous.
When he tried
to repeat his experiment on February 26 and again on February 27 Paris was
gray.
He put the covered photographic plate away in a dark drawer, uranium
salt in place.
On March 1 he decided to go ahead and develop the plate,
“expecting to find the images very feeble.
On the contrary, the silhouettes
appeared with great intensity.
I thought at once that the action might be able
to go on in the dark.” Energetic, penetrating radiation from inert matter
unstimulated by rays or light: now Rutherford had his subject, as Marie and
Pierre Curie, looking for the pure element that radiated, had their
backbreaking work.
136
* * *
Between 1898, when Rutherford first turned his attention to the
phenomenon Henri Becquerel found and which Marie Curie named
radioactivity, and 1911, when he made the most important discovery of his
life, the young New Zealand physicist systematically dissected the atom.
He studied the radiations emitted by uranium and thorium and named
two of them: “ere are present at least two distinct types of radiation—one
that is very readily absorbed, which will be termed for convenience the α
[alpha] radiation, and the other of a more penetrative character, which will
be termed the β [beta] radiation.” 137 (A Frenchman, P.
V.
Villard, later discovered the third distinct type, a form of high-energy X rays that was
named gamma radiation in keeping with Rutherford’s scheme.
138) e work
was done at the Cavendish, but by the time he published it, in 1899, when he
was twenty-seven, Rutherford had moved to Montreal to become professor
of physics at McGill University.
A Canadian tobacco merchant had given
money there to build a physics laboratory and to endow a number of
professorships, including Rutherford’s.
“e McGill University has a good
name,” Rutherford wrote his mother.
139 “£500 is not so bad [a salary] and as the physical laboratory is the best of its kind in the world, I cannot
complain.”
In 1900 Rutherford reported the discovery of a radioactive gas emanating
from the radioactive element thorium.
140 Marie and Pierre Curie soon
discovered that radium (which they had purified from uranium ores in
1898) also gave off a radioactive gas.
Rutherford needed a good chemist to
help him establish whether the thorium “emanation” was thorium or
something else; fortunately he was able to shanghai a young Oxford man at
McGill, Frederick Soddy, of talent sufficient eventually to earn a Nobel Prize.
“At the beginning of the winter [of 1900],” Soddy remembers, “Ernest
Rutherford, the Junior Professor of Physics, called on me in the laboratory
and told me about the discoveries he had made.
He had just returned with
his bride from New Zealand...
but before leaving Canada for his trip he
had discovered what he called the thorium emanation....
I was, of course,
intensely interested and suggested that the chemical character of the
[substance] ought to be examined.” 141
e gas proved to have no chemical character whatsoever.
at, says
Soddy, “conveyed the tremendous and inevitable conclusion that the
element thorium was slowly and spontaneously transmuting itself into
[chemically inert] argon gas!” Soddy and Rutherford had observed the
spontaneous disintegration of the radioactive elements, one of the major
discoveries of twentieth-century physics.
142 ey set about tracing the way
uranium, radium and thorium changed their elemental nature by radiating
away part of their substance as alpha and beta particles.
ey discovered that
each different radioactive product possessed a characteristic “half-life,” the
time required for its radiation to reduce to half its previously measured
intensity.
e half-life measured the transmutation of half the atoms in an
element into atoms of another element or of a physically variant form of the
same element—an “isotope,” as Soddy later named it.
143 Half-life became a
way to detect the presence of amounts of transmuted substances—“decay
products”—too small to detect chemically.
e half-life of uranium proved
to be 4.5 billion years, of radium 1,620 years, of one decay product of
thorium 22 minutes, of another decay product of thorium 27 days.
Some
decay products appeared and transmuted themselves in minute fractions of
a second—in the twinkle of an eye.
It was work of immense importance to
physics, opening up field aer new field to excited view, and “for more than
two years,” as Soddy remembered aerward, “life, scientific life, became
hectic to a degree rare in the lifetime of an individual, rare perhaps in the
lifetime of an institution.
”144
Along the way Rutherford explored the radiation emanating from the
radioactive elements in the course of their transmutation.
He demonstrated
that beta radiation consisted of high-energy electrons “similar in all respects
to cathode rays.” He suspected, and later in England conclusively proved,
that alpha particles were positively charged helium atoms ejected during
radioactive decay.145 Helium is found captured in the crystalline spaces of
uranium and thorium ores; now he knew why.
An important 1903 paper written with Soddy, “Radioactive change,”
offered the first informed calculations of the amount of energy released by
radioactive decay:
It may therefore be stated that the total energy of radiation during the disintegration of one gram
of radium cannot be less than 108 [i.e., 100,000,000] gram-calories, and may be between 109 and
1010 gram-calories....
e union of hydrogen and oxygen liberates approximately 4 × 103 [i.e.,
4,000] gram-calories per gram of water produced, and this reaction sets free more energy for a
given weight than any other chemical change known.
e energy of radioactive change must
therefore be at least twenty-thousand times, and may be a million times, as great as the energy of
any molecular change.
146
at was the formal scientific statement; informally Rutherford inclined to
whimsical eschatology.
A Cambridge associate writing an article on
radioactivity that year, 1903, considered quoting Rutherford’s “playful
suggestion that, could a proper detonator be found, it was just conceivable
that a wave of atomic disintegration might be started through matter, which
would indeed make this old world vanish in smoke.” Rutherford liked to
quip that “some fool in a laboratory might blow up the universe unawares.”
If atomic energy would never be useful, it might still be dangerous.
147, 148
Soddy, who returned to England that year, examined the theme more
seriously.
Lecturing on radium to the Corps of Royal Engineers in 1904, he
speculated presciently on the uses to which atomic energy might be put:
It is probable that all heavy matter possesses—latent and bound up with the structure of the atom
—a similar quantity of energy to that possessed by radium.
If it could be tapped and controlled
what an agent it would be in shaping the world’s destiny!
e man who put his hand on the lever
by which a parsimonious nature regulates so jealously the output of this store of energy would possess a weapon by which he could destroy the earth if he chose.149
Soddy did not think the possibility likely: “e fact that we exist is a proof
that [massive energetic release] did not occur; that it has not occurred is the
best possible assurance that it never will.
We may trust Nature to guard her
secret.”
H.
G.
Wells thought Nature less trustworthy when he read similar
statements in Soddy’s 1909 book Interpretation of Radium.
“My idea is taken
from Soddy,” he wrote of e World Set Free.
“One of the good old scientific
romances,” he called his novel; it was important enough to him that he
interrupted a series of social novels to write it.
150 Rutherford’s and Soddy’s
discussions of radioactive change therefore inspired the sciencefiction novel
that eventually started Leo Szilard thinking about chain reactions and
atomic bombs.
In the summer of 1903 the Rutherfords visited the Curies in Paris.
Mme.
Curie happened to be receiving her doctorate in science on the day of their
arrival; mutual friends arranged a celebration.
“Aer a very lively evening,”
Rutherford recalled, “we retired about 11 o’clock in the garden, where
Professor Curie brought out a tube coated in part with zinc sulphide and
containing a large quantity of radium in solution.
151 e luminosity was
brilliant in the darkness and it was a splendid finale to an unforgettable day.”
e zinc-sulfide coating fluoresced white, making the radium’s ejection of
energetic particles on its progess down the periodic table from uranium to
lead visible in the darkness of the Paris evening.
e light was bright enough
to show Rutherford Pierre Curie’s hands, “in a very inflamed and painful
state due to exposure to radium rays.” Hands swollen with radiation burns
was another object lesson in what the energy of matter could do.
A twenty-six-year-old German chemist from Frankfurt, Otto Hahn, came
to Montreal in 1905 to work with Rutherford.
Hahn had already discovered
a new “element,” radiothorium, later understood to be one of thorium’s
twelve isotopes.
He studied thorium radiation with Rutherford; together
they determined that the alpha particles ejected from thorium had the same
mass as the alpha particles ejected from radium and those from another
radioactive element, actinium.
e various particles were probably therefore
identical—one conclusion along the way to Rutherford’s proof in 1908 that
the alpha particle was inevitably a charged helium atom.
Hahn went back to
Germany in 1906 to begin a distinguished career as a discoverer of isotopes
and elements; Leo Szilard encountered him working with physicist Lise
Meitner at the Kaiser Wilhelm Institute for Chemistry in the 1920s in Berlin.
Rutherford’s research at McGill unraveling the complex transmutations of
the radioactive elements earned him, in 1908, a Nobel Prize—not in physics
but in chemistry.
He had wanted that prize, writing his wife when she
returned to New Zealand to visit her family in late 1904, “I may have a
chance if I keep going,” and again early in 1905, “ey are all following on
my trail, and if I am to have a chance for a Nobel Prize in the next few years
I must keep my work moving.” e award for chemistry rather than for
physics at least amused him.
152, 153 “It remained to the end a good joke against him,” says his son-in-law, “which he thoroughly appreciated, that he
was thereby branded for all time as a chemist and no true physicist.
”154
An eyewitness to the ceremonies said Rutherford looked ridiculously
young—he was thirty-seven—and made the speech of the evening.155 He
announced his recent confirmation, only briefly reported the month before,
that the alpha particle was in fact helium.
156 e confirming experiment was
typically elegant.
Rutherford had a glassblower make him a tube with
extremely thin walls.
He evacuated the tube and filled it with radon gas, a
fertile source of alpha particles.
e tube was gastight, but its thin walls
allowed alpha particles to escape.
Rutherford surrounded the radon tube
with another glass tube, pumped out the air between the two tubes and
sealed off the space.
“Aer some days,” he told his Stockholm audience
triumphantly, “a bright spectrum of helium was observed in the outer
vessel.” Rutherford’s experiments still stun with their simplicity.
157 “In this
Rutherford was an artist,” says a former student.
“All his experiments had
style.” 158
In the spring of 1907 Rutherford had le Montreal with his family—by
then including a six-year-old daughter, his only child—and moved back to
England.
He had accepted appointment as professor of physics at
Manchester, in the city where John Dalton had first revived the atomic
theory almost exactly a century earlier.
Rutherford bought a house and went
immediately to work.
He inherited an experienced German physicist named
Hans Geiger who had been his predecessor’s assistant.
Years later Geiger
fondly recalled the Manchester days, Rutherford settled in among his gear:
I see his quiet research room at the top of the physics building, under the roof, where his radium was kept and in which so much well-known work on the emanation was carried out.
But I also see
the gloomy cellar in which he had fitted up his delicate apparatus for the study of the alpha rays.
Rutherford loved this room.
One went down two steps and then heard from the darkness
Rutherford’s voice reminding one that a hot-pipe crossed the room at headlevel, and to step over
two water-pipes.
en finally, in the feeble light one saw the great man himself seated at his
apparatus.
159
e Rutherford house was cheerier; another Manchester protégé liked to
recall that “supper in the white-painted dining room on Saturdays and
Sundays preceded pow-wows till all hours in the study on the first floor; tea
on Sundays in the drawing room oen followed a spin on the Cheshire
roads in the motor.” ere was no liquor in the house because Mary
Rutherford did not approve of drinking.160 Smoking she reluctantly allowed
because her husband smoked heavily, pipe and cigarettes both.
Now in early middle age he was famously loud, a “tribal chief,” as a
student said, fond of banter and slang.
He would march around the lab
singing “Onward Christian Soldiers” off key.
He took up room in the world
now; you knew he was coming.
He was ruddy-faced with twinkling blue
eyes and he was beginning to develop a substantial belly.
e diffidence was
well hidden: his handshake was brief, limp and boneless; “he gave the
impression,” says another former student, “that he was shy of physical
contact.” He could still be mortified by condescension, blushing bright red
and turning aside dumbstruck.161 , 162, 163 With his students he was quieter, gentler, solid gold.
“He was a man,” pronounces one in high praise, “who
never did dirty tricks.” 164
Chaim Weizmann, the Russian-Jewish biochemist who was later elected
the first president of Israel, was working at Manchester on fermentation
products in those days.
He and Rutherford became good friends.
“Youthful,
energetic, boisterous,” Weizmann recalled, “he suggested anything but the
scientist.
He talked readily and vigorously on every subject under the sun,
oen without knowing anything about it.
Going down to the refectory for
lunch I would hear the loud, friendly voice rolling up the corridor.”
Rutherford had no political knowledge at all, Weizmann thought, but
excused him on the grounds that his important scientific work took all his
time.165 “He was a kindly person, but he did not suffer fools gladly.”
In September 1907, his first term at Manchester, Rutherford made up a list
of possible subjects for research.
Number seven on the list was “Scattering of
alpha rays.” Working over the years to establish the alpha particle’s identity,
he had come to appreciate its great value as an atomic probe; because it was
massive compared to the high-energy but nearly weightless beta electron, it
interacted vigorously with matter.166 e measure of that interaction could
reveal the atom’s structure.
“I was brought up to look at the atom as a nice
hard fellow, red or grey in colour, according to taste,” Rutherford told a
dinner audience once.
167 By 1907 it was clear to him that the atom was not a
hard fellow at all but was substantially empty space.
e German physicist
Philipp Lenard had demonstrated as much in 1903 by bombarding elements
with cathode rays.
168 Lenard dramatized his findings with a vivid metaphor:
the space occupied by a cubic meter of solid platinum, he said, was as empty
as the space of stars beyond the earth.
But if there was empty space in atoms—void within void—there was
something else as well.
In 1906, at McGill, Rutherford had studied the
magnetic deflection of alpha particles by projecting them through a narrow
defining slit and passing the resulting thin beam through a magnetic field.
At one point he covered half the defining slit with a sheet of mica only about
three thousandths of a centimeter thick, thin enough to allow alpha particles
to go through.
He was recording the results of the experiment on
photographic paper; he found that the edges of the part of the beam covered
with the mica were blurred.
e blurring meant that as the alpha particles
passed through, the atoms of mica were deflecting—scattering—many of
them from a straight line by as much as two degrees of angle.
Since an
intense magnetic field scattered the uncovered alpha particles only a little
more, something unusual was happening.
For a particle as comparatively
massive as the alpha, moving at such high velocity, two degrees was an
enormous deflection.
Rutherford calculated that it would require an
electrical field of about 100 million volts per centimeter of mica to scatter an
alpha particle so far.
169 “Such results bring out clearly,” he wrote, “the fact
that the atoms of matter must be the seat of very intense electrical forces.” It
was just this scattering that he marked down on his list to study.170
To do so he needed not only to count but also to see individual alpha
particles.
At Manchester he accepted the challenge of perfecting the
necessary instruments.
He worked with Hans Geiger to develop an electrical
device that clicked off the arrival of each individual alpha particle into a
counting chamber.
Geiger would later elaborate the invention into the
familiar Geiger counter of modern radiation studies.
ere was a way to make individual alpha particles visible using zinc
sulfide, the compound that coated the tube of radium solution Pierre Curie
had carried into the night garden in Paris in 1903.
A small glass plate coated
with zinc sulfide and bombarded with alpha particles briefly fluoresced at
the point where each particle struck, a phenomenon known as “scintillation”
from the Greek word for spark.
Under a microscope the faint scintillations
in the zinc sulfide could be individually distinguished and counted.
e
method was tedious in the extreme.
It required sitting for at least thirty
minutes in a dark room to adapt the eyes, then taking counting turns of only
a minute at a time—the change signaled by a timer that rang a bell—because
focusing the eyes consistently on a small, dim screen was impossible for
much longer than that.
171 Even through the microscope the scintillations
hovered at the edge of visibility; a counter who expected an experiment to
produce a certain number of scintillations sometimes unintentionally saw
imaginary flashes.
So the question was whether the count was generally
accurate.
Rutherford and Geiger compared the observation counts with
matched counts by the electric method.
When the observation method
proved reliable they put the electric counter away.
It could count, but it
couldn’t see, and Rutherford was interested first of all in locating an alpha
particle’s position in space.
Geiger went to work on alpha scattering, aided by Ernest Marsden, then
an eighteen-year-old Manchester undergraduate.
ey observed alpha
particles coming out of a firing tube and passing through foils of such metals
as aluminum, silver, gold and platinum.
e results were generally consistent
with expectation: alpha particles might very well accumulate as much as two
degrees of total deflection bouncing around among atoms of the plum-
pudding sort.
But the experiment was troubled with stray particles.
172
Geiger and Marsden thought molecules in the walls of the firing tube might
be scattering them.
ey tried eliminating the strays by narrowing and
defining the end of the firing tube with a series of graduated metal washers.
at proved no help.
Rutherford wandered into the room.
e three men talked over the
problem.
Something about it alerted Rutherford’s intuition for promising
side effects.
Almost as an aerthought he turned to Marsden and said, “See
if you can get some effect of alpha particles directly reflected from a metal
surface.” Marsden knew that a negative result was expected—alpha particles
shot through thin foils, they did not bounce back from them—but that
missing a positive result would be an unforgivable sin.173 He took great care
to prepare a strong alpha source.
He aimed the pencil-narrow beam of
alphas at a forty-five degree angle onto a sheet of gold foil.
He positioned his
scintillation screen on the same side of the foil, beside the alpha beam, so
that a particle bouncing back would strike the screen and register as a
scintillation.
Between firing tube and screen he interposed a thick lead plate
so that no direct alpha particles could interfere.
Arrangement of Ernest Marsden’s experiment: A-B, alpha particle source.
R-R, gold foil.
P, lead
plate.
S, zinc sulfide scintillation screen.
M, microscope.
Immediately, and to his surprise, he found what he was looking for.
“I
remember well reporting the result to Rutherford,” he wrote, “...
when I
met him on the steps leading to his private room, and the joy with which I
told him.” 174
A few weeks later, at Rutherford’s direction, Geiger and Marsden
formulated the experiment for publication.
“If the high velocity and mass of
the α-particle be taken into account,” they concluded, “it seems surprising
that some of the α-particles, as the experiment shows, can be turned within
a layer of 6 × 10−5 [i.e.,.00006] cm.
of gold through an angle of 90°, and
even more.
To produce a similar effect by magnetic field, the enormous field
of 109 absolute units would be required.” Rutherford in the meantime went
off to ponder what the scattering meant.
175
He pondered, in the midst of other work, for more than a year.
He had a
first quick intuition of what the experiment portended and then lost it.
176
Even aer he announced his spectacular conclusion he was reluctant to
promote it.
One reason for his reluctance might be that the discovery
contradicted the atomic models J.
J.
omson and Lord Kelvin had
postulated earlier.
ere were physical objections to his interpretation of
Marsden’s discovery that would require working out as well.
Rutherford had been genuinely astonished by Marsden’s results.
“It was
quite the most incredible event that has ever happened to me in my life,” he
said later.
“It was almost as incredible as if you fired a 15-inch shell at a piece
of tissue paper and it came back and hit you.
On consideration I realised
that this scattering backwards must be the result of a single collision, and
when I made calculations I saw that it was impossible to get anything of that
order of magnitude unless you took a system in which the greatest part of
the mass of the atom was concentrated in a minute nucleus.” 177
“Collision” is misleading.
What Rutherford had visualized, making
calculations and drawing diagrammatic atoms on large sheets of good paper,
was exactly the sort of curving path toward and away from a compact,
massive central body that a comet follows in its gravitational pas de deux
with the sun.178 He had a model made, a heavy electromagnet suspended as
a pendulum on thirty feet of wire that grazed the face of another
electromagnet set on a table.179 With the two grazing faces matched in
polarity and therefore repelling each other, the pendulum was deflected into
a parabolic path according to its velocity and angle of approach, just as the
alpha particles were deflected.
He needed as always to visualize his work.
When further experiment confirmed his theory that the atom had a small,
massive nucleus, he was finally ready to go public.
He chose as his forum an
old Manchester organization, the Manchester Literary and Philosophical
Society—“largely the general public,” says James Chadwick, who attended
the historic occasion as a student on March 7, 1911, “...
people interested
in literary and philosophical ideas, largely business people.” 180
e first item on the agenda was a Manchester fruit importer’s report that
he had found a rare snake in a consignment of Jamaica bananas.181 He
exhibited the snake.
en it was Rutherford’s turn.
Only an abstract of the
announcement survives, but Chadwick remembers how it felt to hear it: it
was “a most shattering performance to us, young boys that we were....
We
realized this was obviously the truth, this was it.” 182
Rutherford had found the nucleus of his atom.
He did not yet have an
arrangement for its electrons.
At the Manchester meeting he spoke of “a
central electric charge concentrated at a point and surrounded by a uniform
spherical distribution of opposite electricity equal in amount.” at was
sufficiently idealized for calculation, but it neglected the significant physical
fact that the “opposite electricity” must be embodied in electrons.
183
Somehow they would have to be arranged around the nucleus.
Another mystery.
A Japanese theoretical physicist, Hantaro Nagaoka, had
postulated in 1903 a “Saturnian” model of the atom with flat rings of
electrons revolving like Saturn’s rings around a “positively charged
particle.” 184 Nagaoka adapted the mathematics for his model from James
Clerk Maxwell’s first triumphant paper, published in 1859, “On the stability
of motion of Saturn’s rings.” All Rutherford’s biographers agree that
Rutherford was unaware of Nagaoka’s paper until March 11, 1911—aer the
Manchester meeting—when he heard about it by postcard from a physicist
friend: “Campbell tells me that Nagaoka once tried to deduce a big positive
centre in his atom in order to account for optical effects.” He thereupon
looked up the paper in the Philosophical Magazine and added a discussion of
it to the last page of the full-length paper, “e scattering of a and β particles
by matter and the structure of the atom,” that he sent to the same magazine
in April.185 He described Nagaoka’s atom in that paper as being “supposed to
consist of a central attracting mass surrounded by rings of rotating
electrons.” 186
But it seems that Nagaoka had recently visited him, because the Japanese
physicist wrote from Tokyo on February 22, 1911, thanking him “for the
great kindness you showed me in Manchester.
”1 Yet the two physicists seem
not to have discussed atomic models, or Nagaoka would probably have
continued the discussion in his letter and Rutherford, a totally honest man,
would certainly have acknowledged it in his paper.
187
One reason Rutherford was unaware of Nagaoka’s Saturnian model of the
atom is that it had been criticized and abandoned soon aer Nagaoka
introduced it because it suffered from a severe defect, the same theoretical
defect that marred the atom Rutherford was now proposing.
188 e rings of
Saturn are stable because the force operating between the particles of debris
that make them up—gravity—is attractive.
e force operating between the
electrons of Nagaoka’s Saturnian electron rings, however—negative electric
charge—was repulsive.
It followed mathematically that whenever two or
more electrons equally spaced on an orbit rotated around the nucleus, they
would dri into modes of oscillation—instabilities—that would quickly tear
the atom apart.
What was true for Nagaoka’s Saturnian atom was also true, theoretically,
for the atom Rutherford had found by experiment.
It the atom operated by
the mechanical laws of classical physics, the Newtonian laws that govern
relationships within planetary systems, then Rutherford’s model should not
work.
But his was not a merely theoretical construct.
It was the result of real
physical experiment.
And work it clearly did.
It was as stable as the ages and
it bounced back alpha particles like cannon shells.
Someone would have to resolve the contradiction between classical
physics and Rutherford’s experimentally tested atom.
It would need to be
someone with qualities different from Rutherford’s: not an experimentalist
but a theoretician, yet a theoretician rooted deeply in the real.
He would
need at least as much courage as Rutherford had and equal self-confidence.
He would need to be willing to step through the mechanical looking glass
into a strange, nonmechanical world where what happened on the atomic
scale could not be modeled with planets or pendulums.
As if he had been called to the cause, such a person abruptly appeared in
Manchester.
Writing to an American friend on March 18, 1912, Rutherford
announced the arrival: “Bohr, a Dane, has pulled out of Cambridge and
turned up here to get some experience in radioactive work.” “Bohr” was
Niels Henrick David Bohr, the Danish theoretical physicist.189 He was then
twenty-seven years old.
3
TVi
“ere came into the room a slight-looking boy,” Ernest Rutherford’s McGill
colleague and biographer A.
S.
Eve recalls of Manchester days, “whom
Rutherford at once took into his study.190 , 191 Mrs.
Rutherford explained to me that the visitor was a young Dane, and that her husband thought very
highly indeed of his work.
No wonder, it was Niels Bohr!” e memory is
odd.
Bohr was an exceptional athlete.
e Danes cheered his university
soccer exploits.
He skied, bicycled and sailed; he chopped wood; he was
unbeatable at Ping-Pong; he routinely took stairs two at a time.
He was also
physically imposing: tall for his generation, with “an enormous domed
head,” says C.
P.
Snow, a long, heavy jaw and big hands.192 He was thinner as
a young man than later and his shock of unruly, combed-back hair might
have seemed boyish to a man of Eve’s age, twelve years older than
Rutherford.
But Niels Bohr was hardly “slight-looking.”
Something other than Bohr’s physical appearance triggered Eve’s
dissonant memory: probably his presence, which could be hesitant.
He was
“much more muscular and athletic than his cautious manner suggested,”
Snow confirms.
“It didn’t help that he spoke with a so voice, not much
above a whisper.” All his life Bohr talked so quietly—and yet indefatigably—
that people strained to hear him.
Snow knew him as “a talker as hard to get
to the point as Henry James in his later years,” but his speech differed
dramatically between public and private and between initial exploration of a
subject and eventual mastery.
193 Publicly, according to Oskar Klein, a
student of Bohr’s and then a colleague, “he took the greatest care to get the
most accurately shaded formulation of the matter.” Albert Einstein admired
Bohr for “uttering his opinions like one perpetually groping and never like
one who [believed himself to be] in the possession of definite truth.
”194 If
Bohr groped through the exploratory phases of his deliberations, with
mastery “his assurance grew and his speech became vigorous and full of
vivid images,” Lise Meitner’s physicist nephew Otto Frisch noted.
195, 196 And
privately, among close friends, says Klein, “he would express himself with
drastic imagery and strong expressions of admiration as well as criticism.
”197
Bohr’s manner was as binary as his speech.
Einstein first met Bohr in
Berlin in the spring of 1920.
“Not oen in life,” he wrote to Bohr aerward,
“has a human being caused me such joy by his mere presence as you did,”
and he reported to their mutual friend Paul Ehrenfest, an Austrian physicist
at Leiden, “I am as much in love with him as you are.” 198 Despite his
enthusiasm Einstein did not fail to observe closely his new Danish friend;
his verdict in Bohr’s thirty-fih year is similar to Eve’s in his twenty-eighth:
“He is like an extremely sensitive child who moves around the world in a
sort of trance.” At first meeting—until Bohr began to speak—the
theoretician Abraham Pais thought the long, heavy face “gloomy” in the
extreme and puzzled at that momentary impression when everyone knew
“its intense animation and its warm and sunny smile.
”199
Bohr’s contributions to twentieth-century physics would rank second only
to Einstein’s.
He would become a scientist-statesman of unmatched
foresight.
To a greater extent than is usually the case with scientists, his sense
of personal identity—his hard-won selood and the emotional values he
grounded there—was crucial to his work.
For a time, when he was a young
man, that identity was painfully divided.
* * *
Bohr’s father, Christian Bohr, was professor of physiology at the University
of Copenhagen.
In Christian Bohr’s case the Bohr jaw extended below a
thick mustache and the face was rounded, the forehead not so high.
He may
have been athletic; he was certainly a sports enthusiast, who encouraged and
helped finance the Akademisk Boldklub for which his sons would one day
play champion soccer (Niels’ younger brother Harald at the 1908 Olympics).
He was progressive in politics; he worked for the emancipation of women;
he was skeptical of religion but nominally conforming, a solid bourgeois
intellectual.
Christian Bohr published his first scientific paper at twenty-two, took a
medical degree and then a Ph.D.
in physiology, studied under the
distinguished physiologist Carl Ludwig at Leipzig.
Respiration was his
special subject and he brought to that research the practice, still novel in the
early 1880s, of careful physical and chemical experiment.
Outside the
laboratory, a friend of his explains, he was a “keen worshipper” of Goethe;
larger issues of philosophy intrigued him.200
One of the great arguments of the day was vitalism versus mechanism, a
disguised form of the old and continuing debate between those, including
the religious, who believe that the world has purpose and those who believe
it operates automatically and by chance or in recurring unprogressive cycles.
e German chemist who scoffed in 1895 at the “purely mechanical world”
of “scientific materialism” that would allow a butterfly to turn back into a
caterpillar was disputing the same issue, an issue as old as Aristotle.
In Christian Bohr’s field of expertise it emerged in the question whether
organisms and their subsystems—their eyes, their lungs—were assembled to
preexisting purpose or according to the blind and unbreathing laws of
chemistry and of evolution.
e extreme proponent of the mechanistic
position in biology then was a German named Ernst Heinrich Haeckel, who
insisted that organic and inorganic matter were one and the same.
Life arose
by spontaneous generation, Haeckel argued; psychology was properly a
branch of physiology; the soul was not immortal nor the will free.
Despite
his commitment to scientific experiment Christian Bohr chose to side
against Haeckel, possibly because of his worship of Goethe.
He had then the
difficult work of reconciling his practice with his views.
Partly for that reason, partly to enjoy the company of friends, he began
stopping at a café for discussions with the philosopher Harald Høffding aer
the regular Friday sessions of the Royal Danish Academy of Sciences and
Letters, of which they were both members.
e congenial physicist C.
Christensen, who spent his childhood as a shepherd, soon added a third
point of view.
e men moved from café meetings to regular rotation among
their homes.
e philologist Vilhelm omsen joined them to make a
formidable foursome: a physicist, a biologist, a philologist, a philosopher.
Niels and Harald Bohr sat at their feet all through childhood.
As earnest of his commitment to female emancipation Christian Bohr
taught review classes to prepare women for university study.
One of his
students was a Jewish banker’s daughter, Ellen Adler.
Her family was
cultured, wealthy, prominent in Danish life; her father was elected at various
times to both the lower and upper houses of the Folketing, the Danish
parliament.
Christian Bohr courted her; they were married in 1881.
She had
a “lovable personality” and great unselfishness, a friend of her sons would
say.201 Apparently she submerged her Judaism aer her marriage.
Nor did
she matriculate at the university as she must originally have planned.
Christian and Ellen Bohr began married life in the Adler family
townhouse that faced, across a wide street of ancient cobbles, Christianborg
Palace, the seat of the Folketing.
Niels Bohr was born in that favorable place
on October 7, 1885, second child and first son.
When his father accepted an
appointment at the university in 1886 the Bohr family moved to a house
beside the Surgical Academy, where the physiology laboratories were
located.
ere Niels and his brother Harald, nineteen months younger, grew
up.
* * *
As far back as Niels Bohr could remember, he liked to dream of great
interrelationships.
His father was fond of speaking in paradoxes; Niels may
have discovered his dreaming in that paternal habit of mind.202 , 203 At the same time the boy was profoundly literal-minded, a trait oen undervalued
that became his anchoring virtue as a physicist.
Walking with him when he
was about three years old, his father began pointing out the balanced
structure of a tree—the trunk, the limbs, the branches, the twigs—
assembling the tree for his son from its parts.
e literal child saw the
wholeness of the organism and dissented: if it wasn’t like that, he said, it
wouldn’t be a tree.
Bohr told that story all his life, the last time only days
before he died, seventy-eight years old, in 1962.
“I was from first youth able
to say something about philosophical questions,” he summarized proudly
then.
And because of that ability, he said, “I was considered something of a
different character.” 204
Harald Bohr was bright, witty, exuberant and assumed at first to be the
smarter of the two brothers.
“At a very early stage, however,” says Niels
Bohr’s later collaborator and biographer Stefan Rozental, “Christian Bohr
took the opposite view; he realized Niels’ great abilities and special gis and
the extent of his imagination.” e father phrased his realization in what
would have been a cruel comparison if the brothers had been less
devoted.
205 Niels, he pronounced, was “the special one in the family.
”206
Assigned in the fih grade to draw a house, Niels produced a remarkably
mature drawing but counted the fence pickets first.
He liked carpentry and
metalworking; he was household handyman from an early age.
“Even as a
child [he] was considered the thinker of the family,” says a younger
colleague, “and his father listened closely to his views on fundamental
problems.” He almost certainly had trouble learning to write and always had
trouble writing.207 , 208 His mother served loyally as his amanuensis: he dictated his schoolwork to her and she copied it down.
He and Harald bonded in childhood close as twins.
“ere runs like a
leitmotif above all else,” Rozental notices, “the inseparability that
characterized the relationship between the two brothers.” ey spoke and
thought “à deux” recalls one of their friends.209 , 210 “In my whole youth,”
Bohr reminisced, “my brother played a very large part....
I had very much
to do with my brother.
He was in all respects more clever than I.” Harald in
his turn told whoever asked that he was merely an ordinary person and his
brother pure gold, and seems to have meant it.
211, 212
Speech is a clumsiness and writing an impoverishment.
Not language but
the surface of the body is the child’s first map of the world, undifferentiated
between subject and object, coextensive with the world it maps until
awakening consciousness divides it off.
Niels Bohr liked to show how a stick
used as a probe—a blind man’s cane, for example—became an extension of
the arm.
213 Feeling seemed to move to the end of the stick, he said.
e
observation was one he oen repeated—it struck his physicist protégés as
wondrous—like the story of the boy and the tree, because it was charged
with emotional meaning for him.
He seems to have been a child of deep connection.
at is a preverbal gi.
His father, with his own Goethesque yearnings for purpose and wholeness—
for natural unity, for the oceanic consolations of religion without the antique
formalisms—especially sensed it.
His overvalued expectation burdened the
boy.
Religious conflict broke early.
Niels “believed literally what he learnt from
the lessons on religion at school,” says Oskar Klein.
“For a long time this
made the sensitive boy unhappy on account of his parents’ lack of faith.”
Bohr at twenty-seven, in a Christmastime letter to his fiancée from
Cambridge, remembered the unhappiness as paternal betrayal: “I see a little
boy in the snow-covered street on his way to church.
214 It was the only day
his father went to church.
Why?
So the little boy would not feel different
from other little boys.
He never said a word to the little boy about belief or
doubt, and the little boy believed with all of his heart.” 215
e difficulty with writing was a more ominous sign.
e family patched
the problem over by supplying him with his mother’s services as a secretary.
He did not compose mentally while alone and then call in his helper.
He
composed on the spot, laboriously.
at was the whispering that reminded
C.
P.
Snow of the later Henry James.
As an adult Bohr draed and redraed
even private letters.
His reworking of scientific papers in dra and then
repeatedly in proof became legendary.216 Once aer continued appeals to
Zurich for the incomparable critical aid of the Austrian theoretical physicist
Wolfgang Pauli, who knew Bohr well, Pauli responded warily, “If the last
proof is sent away, then I will come.” Bohr collaborated first with his mother
and with Harald, then with his wife, then with a lifelong series of younger
physicists.217 ey cherished the opportunity of working with Bohr, but the
experience could be disturbing.
He wanted not only their attention but also
their intellectual and emotional commitment: he wanted to convince his
collaborators that he was right.
Until he succeeded he doubted his
conclusions himself, or at least doubted the language of their formulation.
Behind the difficulty with writing lay another, more pervasive difficulty.
It
took the form of anxiety that without the extraordinary support of his
mother and his brother would have been crippling.
For a time, it was.
218
It may have emerged first as religious doubt, which appeared, according to
Klein, when Niels was “a young man.” Bohr doubted as he had believed,
“with unusual resolution.” By the time he matriculated at the University of
Copenhagen in the autumn of 1903, when he was eighteen, the doubt had
become pervasive, intoxicating him with terrifying infinities.219
Bohr had a favorite novel.
Its author, Poul Martin Møller, introduced En
Dansk Students Eventyr (e Adventures of a Danish Student) as a reading
before the University of Copenhagen student union in 1824.
It was
published posthumously.
It was short, witty and deceptively lighthearted.
In
an important lecture in 1960, “e Unity of Human Knowledge,” Bohr
described Møller’s book as “an unfinished novel still read with delight by the
older as well as the younger generation in [Denmark].” It gives, he said, “a
remarkably vivid and suggestive account of the interplay between the
various aspects of our position [as human beings].
”220 Aer the Great War
the Danish government helped Bohr establish an institute in Copenhagen.
e most promising young physicists in the world pilgrimaged to study
there.
221 “Every one of those who came into closer contact with Bohr at the
Institute,” writes his collaborator Léon Rosenfeld, “as soon as he showed
himself sufficiently proficient in the Danish language, was acquainted with
the little book: it was part of his initiation.
”222
What magic was contained in the little book?
It was the first Danish novel
with a contemporary setting: student life, and especially the extended
conversations of two student cousins, one a “licentiate”—a degree candidate
—the other a “philistine.” e philistine is a familiar type, says Bohr, “very
soberly efficient in practical affairs”; the licentiate, more exotic, “is addicted
to remote philosophical meditations detrimental to his social activities.
”223
Bohr quotes one of the licentiate’s “philosophical meditations”:
[I start] to think about my own thoughts of the situation in which I find myself.
I even think that I
think of it, and divide myself into an infinite retrogressive sequence of “I’s” who consider each other.
I do not know at which “I” to stop as the actual, and in the moment I stop at one, there is
indeed again an “I” which stops at it.
I become confused and feel a dizziness as if I were looking
down into a bottomless abyss.
224
“Bohr kept coming back to the different meanings of the word ‘I,’ ” Robert
Oppenheimer remembered, “the ‘I’ that acts, the ‘I,’ that thinks, the ‘I,’ that
studies itself.
”225
Other conditions that trouble the licentiate in Møller’s novel might be
taken from a clinical description of the conditions that troubled the young
Niels Bohr.
is disability, for example:
Certainly I have seen thoughts put on paper before; but since I have come distinctly to perceive the
contradiction implied in such an action, I feel completely incapable of forming a single written
sentence....
I torture myself to solve the unaccountable puzzle, how one can think, talk, or write.
You see, my friend, a movement presupposes a direction.
e mind cannot proceed without
moving along a certain line; but before following this line, it must already have thought it.
erefore one has already thought every thought before one thinks it.
us every thought, which
seems the work of a minute, presupposes an eternity.
is could almost drive me to madness.
226
Or this complaint, on the fragmentation of the self and its multiplying
duplicity, which Bohr in later years was wont to quote:
us on many occasions man divides himself into two persons, one of whom tries to fool the
other, while a third one, who is in fact the same as the other two, is filled with wonder at this
confusion.
In short, thinking becomes dramatic and quietly acts the most complicated plots with itself and for itself; and the spectator again and again becomes actor.227
“Bohr would point to those scenes,” Rosenfeld notes, “in which the
licentiate describes how he loses the count of his many egos, or [discourses]
on the impossibility of formulating a thought, and from these fanciful
antinomies he would lead his interlocutor...
to the heart of the problem of
unambiguous communication of experience, whose earnestness he thus
dramatically emphasized.” 228 Rosenfeld worshiped Bohr; he failed to see, or
chose not to report, that for Bohr the struggles of the licentiate were more
than “fanciful antinomies.”
Ratiocination—that is the technical term for what the licentiate does, the
term for what the young Bohr did as well—is a defense mechanism against
anxiety.
ought spirals, panicky and compulsive.
Doubt doubles and
redoubles, paralyzing action, emptying out the world.
e mechanism is
infinitely regressive because once the victim knows the trick, he can doubt
anything, even doubt itself.
Philosophically the phenomenon could be
interesting, but as a practical matter ratiocination is a way of stalling.
If work
is never finished, its quality cannot be judged.
e trouble is that stalling
postpones the confrontation and adds that guilt to the burden.
Anxiety
increases; the mechanism accelerates its spiraling flights; the self feels as if it
will fragment; the multiplying “I” dramatizes the feeling of impending
breakup.
At that point madness reveals its horrors; the image that recurred
in Bohr’s conversation and writing throughout his life was the licentiate’s
“bottomless abyss.
”229 We are “suspended in language,” Bohr liked to say,
evoking that abyss; and one of his favorite quotations was two lines from
Schiller:230
Nur die Fülle führt zur Klarheit, 231
Und im Abgrund wohnt die Wahrheit
Only wholeness leads to clarity,
And truth lies in the abyss.
But it was not in Møller that Bohr found solid footing.
He needed more than
a novel, however apposite, for that.
He needed what we all need for sanity:
he needed love and work.
“I took a great interest in philosophy in the years aer my [high school]
examination,” Bohr said in his last interview.
“I came especially in close
connection with Høffding.” 232 Harald Høffding was Bohr’s father’s old
friend, the other charter member of the Friday-night discussion group.
233
Bohr had known him from childhood.
Born in 1843, he was twelve years
older than Christian Bohr, a profound, sensitive and kindly man.
He was a
skillful interpreter of the work of Søren Kierkegaard and of William James
and a respected philosopher in his own right: an anti-Hegelian, a pragmatist
interested in questions of perceptive discontinuity.
Bohr became a Høffding
student.
It seems certain he also turned personally to Høffding for help.
He
made a good choice.
Høffding had struggled through a crisis of his own as a
young man, a crisis that brought him, he wrote later, near “despair.” 234
Høffding was twelve years old when Søren Kierkegaard died of a lung
infection in chill November 1855, old enough to have heard of the near-riot
at the grave a somber walk outside the city walls, old enough for the strange,
awkward, fiercely eloquent poet of multiple pseudonyms to have been a
living figure.
With that familiarity as a point of origin Høffding later turned
to Kierkegaard’s writings for solace from despair.
He found it especially in
Stages on Life’s Way, a black-humorous dramatization of a dialectic of
spiritual stages, each independent, disconnected, bridgeable only by an
irrational leap of faith.
Høffding championed the prolific and difficult Dane
in gratitude; his second major book, published in 1892, would help establish
Kierkegaard as an important philosopher rather than merely a literary stylist
given to outbursts of raving, as Danish critics had first chosen to regard him.
Kierkegaard had much to offer Bohr, especially as Høffding interpreted
him.
Kierkegaard examined the same states of mind as had Poul Martin
Møller.
Møller taught Kierkegaard moral philosophy at the university and
seems to have been a guide.
235 Aer Møller’s death Kierkegaard dedicated
e Concept of Dread to him and referred to him in a dra of the dedication
as “my youth’s enthusiasm, my beginning’s confidant, mighty trumpet of my
awakening, my departed friend.
”236 From Møller to Kierkegaard to Høffding
to Bohr: the line of descent was direct.
Kierkegaard notoriously suffered from a proliferation of identities and
doubts.
e doubling of consciousness is a central theme in Kierkegaard’s
work, as it was in Møller’s before him.
It would even seem to be a hazard of
long standing among the Danes.
e Danish word for despair, Fortvivlelse,
carries lodged at its heart the morpheme tvi, which means “two” and
signifies the doubling of consciousness.237 Tvivl in Danish means “doubt”;
Tvivlesyg means “skepticism”; Tvetydighed, “ambiguity.” e self watching
itself is indeed a commonplace of puritanism, closely akin to the Christian
conscience.
But unlike Møller, who jollies the licentiate’s Tvivl away, Kierkegaard
struggled to find a track through the maze of mirrors.
Høffding, in his
History of Modern Philosophy, which Bohr would have read as an
undergraduate, summarizes the track he understood Kierkegaard to have
found: “His leading idea was that the different possible conceptions of life
are so sharply opposed to one another that we must make a choice between
them, hence his catchword either-or; moreover, it must be a choice which
each particular person must make for himself, hence his second catchword,
the individual.” And, following: “Only in the world of possibilities is there
continuity; in the world of reality decision always comes through a breach of
continuity.
”238, 239 Continuity in the sense that it afflicted Bohr was the proliferating stream of doubts and “I’s” that plagued him; a breach of that
continuity—decisiveness, function—was the termination he hoped to find.
He turned first to mathematics.
He learned in a university lecture about
Riemannian geometry, a type of non-Euclidean geometry developed by the
German mathematician Georg Riemann to represent the functions of
complex variables.
Riemann showed how such multivalued functions (a
number, its square root, its logarithm and so on) could be represented and
related on a stack of coincident geometric planes that came to be called
Riemann surfaces.
“At that time,” Bohr said in his last interview, “I really
thought to write something about philosophy, and that was about this
analogy with multivalued functions.
240 I felt that the various problems in
psychology—which were called the big philosophical problems, of the free
will and such things—that one could really reduce them when one
considered how one really went about them, and that was done on the
analogy to multivalued functions.” By then he thought the problem might be
one of language, of the ambiguity—the multiple values, as it were—between
different meanings of the word “I.” Separate each different meaning on a
different plane and you could keep track of what you were talking about.
e
confusion of identities would resolve itself graphically before one’s eyes.
e scheme was too schematic for Bohr.
Mathematics was probably too
much like ratiocination, leaving him isolated within his anxiety.
He thought
of writing a book about his mathematical analogies but leapt instead to work
that was far more concrete.
But notice that the mathematical analogy begins
to embed the problem of doubt within the framework of language,
identifying doubt as a specialized form of verbal ambiguity, and notice that
it seeks to clarify ambiguities by isolating their several variant meanings on
separate, disconnected planes.
e solid work Bohr took up, in February 1905, when he was nineteen
years old, was a problem in experimental physics.
241 Each year the Royal
Danish Academy of Sciences and Letters announced problems for study
against a two-year deadline, aer which the academy awarded gold and
silver medals for successful papers.
In 1905 the physics problem was to
determine the surface tension of a number of liquids by measuring the
waves produced in those liquids when they were allowed to run out through
a hole (the braided cascade of a garden hose demonstrates such waves).
e
method had been proposed by the British Nobelist John William Strutt,
Lord Rayleigh, but no one had yet tried it out.
Bohr and one other
contestant accepted the challenge.
Bohr went to work in the physiology laboratory where he had watched
and then assisted his father for years, learning the cra of experiment.
To
produce stable jets he decided to use drawn-out glass tubes.
Because the
method required large quantities of liquid he limited his experiment to
water.
e tubes had to be flattened on the sides to make an oval cross
section; that gave the jet of water the shape it needed to evolve braidlike
waves.
All the work of heating, soening and drawing out the tubes Bohr
did himself; he found it hypnotic.
Rosenfeld says Bohr “took such delight in
this operation that, completely forgetting its original purpose, he spent
hours passing tube aer tube through the flame.
”242
Each separate experimental determination of the surface-tension value
took hours.
It had to be done at night, when the lab was unoccupied,
because the jets were easily disturbed by vibration.
Slow work, but Bohr also
dawdled.
e academy had allowed two years.
Toward the end of that time
Christian Bohr realized his son was procrastinating to the point where he
might not finish his paper before the deadline.
“e experiments had no
end,” Bohr told Rosenfeld some years later on a bicycle ride in the country;
“I always noticed new details that I thought I had first to understand.
At last
my father sent me out here, away from the laboratory, and I had to write up
the paper.” 243
“Out here” was Naerumgaard, the Adler country estate north of
Copenhagen.
ere, away from the temptations of the laboratory, Niels
wrote and Harald transcribed an essay of 114 pages.
Niels submitted it to the
academy on the day of deadline, but even then it was incomplete; three days
later he turned in an eleven-page addendum that had been accidentally le
off.
e essay, Bohr’s first scientific paper, determined the surface tension only
of water but also uniquely extended Rayleigh’s theory.
It won a gold medal
from the academy.
It was an outstanding achievement for someone so young
and it set Bohr’s course for physics.
Unlike mathematicized philosophy,
physics was anchored solidly in the real world.
In 1909 the Royal Society of London accepted the surface-tension paper
in modified form for its Philosophical Transactions.
Bohr, who was still only
a student working toward his master’s degree when the essay appeared, had
to explain to the secretary of the society, who had addressed him by his
presumed academic title, that he was “not a professor.
”244
Retreating to the country had helped him once.
It might help again.
Naerumgaard ceased to be available when the Adler family donated it for
use as a school.
When the time came to study for his master’s degree
examinations, between March and May 1909, Bohr traveled to Vissenbjerg,
on the island of Funen, the next island west from Copenhagen’s Zealand, to
stay at the parsonage of the parents of Christian Bohr’s laboratory assistant.
Niels procrastinated on Funen by reading Stages on Life’s Way.
e day he
finished it he enthusiastically mailed the book to Harald.
“is is the only
thing I have to send,” he wrote his younger brother; “nevertheless, I don’t
think I could easily find anything better....
It is something of the finest I
have ever read.” 245 At the end of June, back in Copenhagen, again on
deadline day, Bohr turned in his master’s thesis, copied out in his mother’s
hand.
Harald had sprinted ahead of him by then, having won his M.Sc.
in April
and gone off to the Georgia-Augusta University in Gottingen, Germany, the
center of European mathematics, to study for his Ph.D.
He received that
degree in Göttingen in June 1910.
Niels wrote his younger brother tongue-
in-cheek that his “envy would soon be growing over the rooops,” but in fact
he was happy with his progress on his own doctoral dissertation despite
having spent “four months speculating about a silly question about some
silly electrons and [succeeding] only in writing circa fourteen more or less
divergent rough dras.
”246, 247 Christensen had posed Bohr a problem in the electron theory of metals for his master’s thesis; the subject interested Bohr
enough to continue pursuing it as his doctoral work.
He was specializing in
theoretical studies now; to try to do experimental work too, he explained,
was “unpractical.” 248
He returned to the parsonage at Vissenbjerg in the autumn of 1910.
His
work slowed.
He may have recalled the licentiate’s dissertation problems, for
he again turned to Kierkegaard.
“He made a powerful impression on me
when I wrote my dissertation in a parsonage in Funen, and I read his works
night and day,” Bohr told his friend and former student J.
Rud Nielsen in
1933.
“His honesty and his willingness to think the problems through to
their very limit is what is great.
And his language is wonderful, oen
sublime.
ere is of course much in Kierkegaard that I cannot accept.
I
ascribe that to the times in which he lived.
But I admire his intensity and
perseverance, his analysis to the utmost limit, and the fact that through
these qualities he turned misfortune and suffering into something good.” 249
He finished his Ph.D.
thesis, “Studies in the electron theory of metals,” by
the end of January 1911.
On February 3, suddenly, at fiy-six, his father
died.
He dedicated his thesis “in deepest gratitude to the memory of my
father.
”250 He loved his father; if there had been a burden of expectation he
was free of that burden now.
As was customary, he publicly defended his thesis in Copenhagen on May
13.
“Dr.
Bohr, a pale and modest young man,” the Copenhagen newspaper
Dagbladet reported under a crude drawing of the candidate standing in
white tie and tails at a heavy lectern, “did not take much part in the
proceedings, whose short duration is a record.
”251 e small hall was
crowded to overflowing.
Christiansen, one of the two examiners, said simply
that hardly anyone in Denmark was well enough informed on the subject to
judge the candidate’s work.
Before he died Christian Bohr had helped arrange a fellowship from the
Carlsberg Foundation for his son for study abroad.
Niels spent the summer
sailing and hiking with Margrethe Nørland, the sister of a friend, a beautiful
young student whom he had met in 1910 and to whom, shortly before his
departure, he became engaged.
en he went off in late September to
Cambridge.
He had arranged to study at the Cavendish under J.
J.
omson.
29 Sept.
1911
Eltisley Avenue 10,
Newnham, Cambridge
Oh Harald!
252
ings are going so well for me.
I have just been talking to J.
J.
omson and have explained to him, as well as I could, my ideas about
radiation, magnetism, etc.
If you only knew what it meant to me to talk to
such a man.
He was extremely nice to me, and we talked about so much;
and I do believe that he thought there was some sense in what I said.
He is
now going to read [my dissertation] and he invited me to have dinner
with him Sunday at Trinity College; then he will talk with me about it.
You can imagine that I am happy....
I now have my own little flat.
It is at
the edge of town and is very nice in all respects.
I have two rooms and eat
all alone in my own room.
It is very nice here; now, as I am sitting and
writing to you, it blazes and rumbles in my own little fireplace.
Niels Bohr was delighted with Cambridge.
His father’s Anglophilia had
prepared him to like English settings; the university offered the tradition of
Newton and Clerk Maxwell and the great Cavendish Laboratory with its
awesome record of physical discovery.
Bohr found that his schoolboy
English needed work and set out reading David Copperfield with an
authoritative new dictionary at hand, looking up every uncertain word.
He
discovered that the laboratory was crowded and undersupplied.
On the
other hand, it was amusing to have to go about in cap and gown (once he
was admitted to Trinity as a research student) “under threat of high fines,” to
see the Trinity high table “where they eat so much and so first-rate that it is
quite unbelievable and incomprehensible that they can stand it,” to walk “for
an hour before dinner across the most beautiful meadows along the river,
with the hedges flecked with red berries and with isolated windblown willow
trees—imagine all this under the most magnificent autumn sky with
scurrying clouds and blustering wind.” 253, 254 He joined a soccer club; called on physiologists who had been students of his father; attended physics
lectures; worked on an experiment omson had assigned him; allowed the
English ladies, “absolute geniuses at drawing you out,” to do their duty by
him at dinner parties.255
But omson never got around to reading his dissertation.
e first
meeting had not, in fact, gone so well.
e new student from Denmark had
done more than explain his ideas; he had shown omson the errors he
found in omson’s electron-theory work.
“I wonder,” Bohr wrote
Margrethe soon aer, “what he will say to my disagreement with his
ideas.
”256 And a little later: “I’m longing to hear what omson will say.
He’s
a great man.
I hope he will not get angry with my silly talk.
”257
omson may or may not have been angry.
He was not much interested in
electrons anymore.
He had turned his attention to positive rays—the
experiment he assigned Bohr concerned such rays and Bohr found it
distinctly unpromising—and in any case had very little patience with
theoretical discussions.
“It takes half a year to get to know an Englishman,”
Bohr said in his last interview.
“...
It was the custom in England that they
would be polite and so on, but they wouldn’t be interested to see
anybody....
258 I went Sundays to the dinner in Trinity College....
I was
sitting there, and nobody spoke to me ever in many Sundays.
But then they
understood that I was not more eager to speak to them than they were to
speak to me.
And then we were friends, you see, and then the whole thing
was different.” e insight is generalized; omson’s indifference was
perhaps its first specific instance.
en Rutherford turned up at Cambridge.
He “came down from Manchester to speak at the annual Cavendish
Dinner,” says Bohr.
“Although on this occasion I did not come into personal
contact with [him], I received a deep impression of the charm and power of
his personality by which he had been able to achieve almost the incredible
wherever he worked.
e dinner”—in December—“took place in a most
humorous atmosphere and gave the opportunity for several of Rutherford’s
colleagues to recall some of the many anecdotes which already then were
attached to his name.” 259 Rutherford spoke warmly of the recent work of the
physicist C.
T.
R.
Wilson, the inventor of the cloud chamber (which made
the paths of charged particles visible as lines of water droplets hovering in
supersaturated fog) and a friend from Cambridge student days.
Wilson had
“just then,” says Bohr, photographed alpha particles in his cloud chamber
scattering from interactions with nuclei, “the phenomenon which only a few
months before had led [Rutherford] to his epoch-making discovery of the
atomic nucleus.
”260
Bohr had matters on his mind that he would soon relate to the problem of
the nucleus and its theoretically unstable electrons, but it was Rutherford’s
enthusiastic informality that most impressed him at the annual dinner.
261
Remembering this period of his life long aerward, he would single out for
special praise among Rutherford’s qualities “the patience to listen to every
young man when he felt he had any idea, however modest, on his mind.” 262
In contrast, presumably, to J.
J.
omson, whatever omson’s other virtues.
Soon aer the dinner Bohr went up to Manchester to visit “one of my
recently deceased father’s colleagues who was also a close friend of
Rutherford,” whom Bohr wanted to meet.
263 e close friend brought them
together.
Rutherford looked over the young Dane and liked what he saw
despite his prejudice against theoreticians.
Someone asked him later about
the discrepancy.
“Bohr’s different,” Rutherford roared, disguising affection
with bluster.
“He’s a football player!” Bohr was different in another regard as
well; he was easily the most talented of all Rutherford’s many students—and
Rutherford trained no fewer than eleven Nobel Prize winners during his life,
an unsurpassed record.
264, 265
Bohr held up his decision between Cambridge and Manchester until he
could go over everything with Harald, who visited him in Cambridge in
January 1912 for the purpose.
en Bohr eagerly wrote Rutherford for
permission to study at Manchester, as they had discussed in December.
Rutherford had advised him then not to give up on Cambridge too quickly
—Manchester is always here, he told him, it won’t run away—and so Bohr
proposed to arrive for spring term, which began in late March.266
Rutherford gladly agreed.
Bohr felt he was being wasted at Cambridge.
He
wanted substantial work.
His first six weeks in Manchester he spent following “an introductory
course on the experimental methods of radioactive research,” with Geiger
and Marsden among the instructors.
267 He continued pursuing his
independent studies in electron theory.
He began a lifelong friendship with a
young Hungarian aristocrat, George de Hevesy, a radiochemist with a long,
sensitive face dominated by a towering nose.
De Hevesy’s father was a court
councillor, his mother a baroness; as a child he had hunted partridge in the
private game park of the Austro-Hungarian emperor Franz Josef next to his
grandfather’s estate.
Now he was working to meet a challenge Rutherford
had thrown at him one day to separate radioactive decay products from
their parent substances.
Out of that work he developed over the next several
decades the science of using radioactive tracers in medical and biological
research, one more useful offspring of Rutherford’s casual but fecund
paternity.
Bohr learned about radiochemistry from de Hevesy.
268 He began to see
connections with his electron-theory work.
His sudden burst of intuitions
then was spectacular.
He realized in the space of a few weeks that radioactive
properties originated in the atomic nucleus but chemical properties
depended primarily on the number and distribution of electrons.
He
realized—the idea was wild but happened to be true—that since the
electrons determined the chemistry and the total positive charge of the
nucleus determined the number of electrons, an element’s position on the
periodic table of the elements was exactly the nuclear charge (or “atomic
number”): hydrogen first with a nuclear charge of 1, then helium with a
nuclear charge of 2 and so on up to uranium at 92.
De Hevesy remarked to him that the number of known radio elements
already far outnumbered the available spaces on the periodic table and Bohr
made more intuitive connections.
Soddy had pointed out that the radio
elements were generally not new elements, only variant physical forms of the
natural elements (he would soon give them their modern name, isotopes).
Bohr realized that the radio elements must have the same atomic number as
the natural elements with which they were chemically identical.
at
enabled him to rough out what came to be called the radioactive
displacement law: that when an element transmutes itself through
radioactive decay it shis its position on the periodic table two places to the
le if it emits an alpha particle (a helium nucleus, atomic number 2), one
place to the right if it emits a beta ray (an energetic electron, which leaves
behind in the nucleus an extra positive charge).
Periodic table of the elements.
The lanthanide series (“rare earths”), beginning with lanthanum
(57), and the actinide series, which begins with actinium (89) and includes thorium (90) and
uranium (92), are chemically similar.
Other families of elements read vertically down the table—
at the far right, for example, the noble gases: helium, neon, argon, krypton, xenon, radon.
All these first rough insights would be the work of other men’s years to
anchor soundly in theory and experiment.
Bohr ran them in to Rutherford.
To his surprise, he found the discoverer of the nucleus cautious about his
own discovery.
“Rutherford...
thought that the meagre evidence [so far
obtained] about the nuclear atom was not certain enough to draw such
consequences,” Bohr recalled.269 “And I said to him that I was sure that it
would be the final proof of his atom.” If not convinced, Rutherford was at
least impressed; when de Hevesy asked him a question about radiation one
day Rutherford responded cheerfully, “Ask Bohr!
”270
Rutherford was well prepared for surprises, then, when Bohr came to see
him again in mid-June.
Bohr told Harald what he was on to in a letter on
June 19, aer the meeting:
It could be that I’ve perhaps found out a little bit about the structure of
atoms.
You must not tell anyone anything about it, otherwise I certainly
could not write you this soon.
If I’m right, it would not be an indication of
the nature of a possibility...
but perhaps a little piece of reality....
You
understand that I may yet be wrong, for it hasn’t been worked out fully yet
(but I don’t think so); nor do I believe that Rutherford thinks it’s
completely wild; he is the right kind of man and would never say that he
was convinced of something that was not entirely worked out.
You can
imagine how anxious I am to finish quickly.
271
Bohr had caught a first glimpse of how to stabilize the electrons that
orbited with such theoretical instability around Rutherford’s nucleus.
Rutherford sent him off to his rooms to work it out.
Time was running
short; he planned to marry Margrethe Nørland in Copenhagen on August 1.
He wrote Harald on July 17 that he was “getting along fairly well; I believe I
have found out a few things; but it is certainly taking more time to work
them out than I was foolish enough to believe at first.
272 I hope to have a
little paper ready to show to Rutherford before I leave, so I’m busy, so busy;
but the unbelieveable heat here in Manchester doesn’t exactly help my
diligence.
How I look forward to talking to you!” By the following
Wednesday, July 22, he had seen Rutherford, won further encouragement,
and was making plans to meet Harald on the way home.
273
Bohr married, a serene marriage with a strong, intelligent and beautiful
woman that lasted a lifetime.
He taught at the University of Copenhagen
through the autumn term.
e new model of the atom he was struggling to
develop continued to tax him.
On November 4 he wrote Rutherford that he
expected “to be able to finish the paper in a few weeks.” 274 A few weeks
passed; with nothing finished he arranged to be relieved of his university
teaching and retreated to the country with Margrethe.
e old system
worked; he produced “a very long paper on all these things.
”275 en an
important new idea came to him and he broke up his original long paper
and began rewriting it into three parts.
“On the constitution of atoms and
molecules,” so proudly and bravely titled—Part I mailed to Rutherford on
March 6, 1913, Parts II and III finished and published before the end of the
year—would change the course of twentieth-century physics.
Bohr won the
1922 Nobel Prize in Physics for the work.
* * *
As far back as Bohr’s doctoral dissertation he had decided that some of the
phenomena he was examining could not be explained by the mechanical
laws of Newtonian physics.
“One must assume that there are forces in nature
of a kind completely different from the usual mechanical sort,” he wrote
then.276 He knew where to look for these different forces: he looked to the
work of Max Planck and Albert Einstein.
Planck was the German theoretician whom Leo Szilard would meet at the
University of Berlin in 1921; born in 1858, Planck had taught at Berlin since
1889.
In 1900 he had proposed a revolutionary idea to explain a persistent
problem in mechanical physics, the so-called ultraviolet catastrophe.
According to classical theory there should be an infinite amount of light
(energy, radiation) inside a heated cavity such as a kiln.
at was because
classical theory, with its continuity of process, predicted that the particles in
the heated walls of the cavity which vibrated to produce the light would
vibrate to an infinite range of frequencies.
Obviously such was not the case.
But what kept the energy in the cavity
from running off infinitely into the far ultraviolet?
Planck began his effort to
find out in 1897 and pursued it for three hard years.
Success came with a
last-minute insight announced at a meeting of the Berlin Physical Society on
October 19, 1900.
Friends checked Planck’s new formula that very night
against experimentally derived values.
ey reported its accuracy to him the
next morning.
“Later measurements, too,” Planck wrote proudly in 1947, at
the end of his long life, “confirmed my radiation formula again and again—
the finer the methods of measurement used, the more accurate the formula
was found to be.” 277
Planck solved the radiation problem by proposing that the vibrating
particles can only radiate at certain energies.
e permitted energies would
be determined by a new number—“a universal constant,” he says, “which I
called h.
Since it had the dimension of action (energy X time), I gave it the
name, elementary quantum of action.
”278 (Quantum is the neuter form of the Latin word quantus, meaning “how great.”) Only those limited and finite
energies could appear which were whole-number multiples of hv: of the
frequency ν times Planck’s h.
Planck calculated h to be a very small number,
close to the modern value of 6.63 × 10−27 erg-seconds.
Universal h soon
acquired its modern name: Planck’s constant.
Planck, a thoroughgoing conservative, had no taste for pursuing the
radical consequences of his radiation formula.
Someone else did: Albert
Einstein.
In a paper in 1905 that eventually won for him the Nobel Prize,
Einstein connected Planck’s idea of limited, discontinuous energy levels to
the problem of the photoelectric effect.
Light shone on certain metals
knocks electrons free; the effect is applied today in the solar panels that
power spacecra.
But the energy of the electrons knocked free of the metal
does not depend, as common sense would suggest, on the brightness of the
light.
It depends instead on the color of the light—on its frequency.
Einstein saw a quantum condition in this odd fact.
He proposed the
heretical possibility that light, which years of careful scientific experiment
had demonstrated to travel in waves, actually traveled in small individual
packets—particles—which he called “energy quanta.” Such photons (as they
are called today), he wrote, have a distinctive energy hv and they transfer
most of that energy to the electrons they strike on the surface of the metal.
A
brighter light thus releases more electrons but not more energetic electrons;
the energy of the electrons released depends on hv and so on the frequency
of the light.
us Einstein advanced Planck’s quantum idea from the status
of a convenient tool for calculation to that of a possible physical fact.
With these advances in understanding Bohr was able to confront the
problem of the mechanical instability of Rutherford’s model of the atom.
In
July, at the time of the “little paper ready to show to Rutherford,” he already
had his central idea.
It was this: that since classical mechanics predicted that
an atom like Rutherford’s, with a small, massive central nucleus surrounded
by orbiting electrons, would be unstable, while in fact atoms are among the
most stable of systems, classical mechanics was inadequate to describe such
systems and would have to give way to a quantum approach.
Planck had
introduced quantum principles to save the laws of thermodynamics;
Einstein had extended the quantum idea to light; Bohr now proposed to
lodge quantum principles within the atom itself.
rough the autumn and early winter, back in Denmark, Bohr pursued
the consequences of his idea.
e difficulty with Rutherford’s atom was that
nothing about its design justified its stability.
If it happened to be an atom
with several electrons, it would fly apart.
Even if it were a hydrogen atom
with only one (mechanically stable) electron, classical theory predicted that
the electron would radiate light as it changed direction in its orbit around
the nucleus and therefore, the system losing energy, would spiral into the
nucleus and crash.
e Rutherford atom, from the point of view of
Newtonian mechanics—as a miniature solar system—ought to be impossibly
large or impossibly small.
Bohr therefore proposed that there must be what he called “stationary
states” in the atom: orbits the electrons could occupy without instability,
without radiating light, without spiraling in and crashing.
He worked the
numbers of this model and found they agreed very well with all sorts of
experimental values.
en at least he had a plausible model, one that
explained in particular some of the phenomena of chemistry.
But it was
apparently arbitrary; it was not more obviously a real picture of the atom
than other useful models such as J.
J.
omson’s plum pudding.
Help came then from an unlikely quarter.
A professor of mathematics at
King’s College, London, J.
W.
Nicholson, whom Bohr had met and thought a
fool, published a series of papers proposing a quantized Saturnian model of
the atom to explain the unusual spectrum of the corona of the sun.
e
papers were published in June in an astronomy journal; Bohr didn’t see
them until December.
He was quickly able to identify the inadequacies of
Nicholson’s model, but not before he felt the challenge of other researchers
breathing down his neck—and not without noticing Nicholson’s excursion
into the jungle of spectral lines.
Oriented toward chemistry, communicating back and forth with George
de Hevesy, Bohr had not thought of looking at spectroscopy for evidence to
support his model of the atom.
“e spectra was a very difficult problem,” he
said in his last interview.
“...
One thought that this is marvelous, but it is
not possible to make progress there.
Just as if you have the wing of a
butterfly, then certainly it is very regular with the colors and so on, but
nobody thought that one could get the basis of biology from the coloring of
the wing of a butterfly.
”279
Taking Nicholson’s hint, Bohr now turned to the wings of the spectral
butterfly.
Spectroscopy was a well-developed field in 1912.
e eighteenth-century
Scottish physicist omas Melvill had first productively explored it.
He
mixed chemical salts with alcohol, lit the mixtures and studied the resulting
light through a prism.
Each different chemical produced characteristic
patches of color.
at suggested the possibility of using spectra for chemical
analysis, to identify unknown substances.
e prism spectroscope, invented
in 1859, advanced the science.
It used a narrow slit set in front of a prism to
limit the patches of light to similarly narrow lines; these could be directed
onto a ruled scale (and later onto strips of photographic film) to measure
their spacing and calculate their wavelengths.
Such characteristic patterns of
lines came to be called line spectra.
Every element had its own unique line
spectrum.
Helium was discovered in the chromosphere of the sun in 1868 as
a series of unusual spectral lines twenty-three years before it was discovered
mixed into uranium ore on earth.
e line spectra had their uses.
But no one understood what produced the lines.
At best, mathematicians
and spectroscopists who liked to play with wavelength numbers were able to
find beautiful harmonic regularities among sets of spectral lines.
Johann
Balmer, a nineteenth-century Swiss mathematical physicist, identified in
1885 one of the most basic harmonies, a formula for calculating the
wavelengths of the spectral lines of hydrogen.
ese, collectively called the
Balmer series, look like this:
Balmer series
It is not necessary to understand mathematics to appreciate the simplicity of
the formula Balmer derived that predicts a line’s location on the spectral
band to an accuracy of within one part in a thousand, a formula that has
only one arbitrary number:
(the Greek letter λ, lambda, stands for the wavelength of the line; η takes the
values 3, 4, 5 and so on for the various lines).
Using his formula, Balmer was
able to predict the wavelengths of lines to be expected for parts of the
hydrogen spectrum not yet studied.
ey were found where he said they
would be.
A Swedish spectroscopist, Johannes Rydberg, went Balmer one better and
published in 1890 a general formula valid for a great many different line
spectra.
e Balmer formula then became a special case of the more general
Rydberg equation, which was built around a number called the Rydberg
constant.
at number, subsequently derived by experiment and one of the
most accurately known of all universal constants, takes the precise modern
value of 109,677 cm−1.
Bohr would have known these formulae and numbers from
undergraduate physics, especially since Christensen was an admirer of
Rydberg and had thoroughly studied his work.
But spectroscopy was far
from Bohr’s field and he presumably had forgotten them.
He sought out his
old friend and classmate, Hans Hansen, a physicist and student of
spectroscopy just returned from Göttingen.
Hansen reviewed the regularity
of line spectra with him.
Bohr looked up the numbers.
“As soon as I saw
Balmer’s formula,” he said aerward, “the whole thing was immediately clear
to me.” 280
What was immediately clear was the relationship between his orbiting
electrons and the lines of spectral light.
Bohr proposed that an electron
bound to a nucleus normally occupies a stable, basic orbit called a ground
state.
Add energy to the atom—heat it, for example—and the electron
responds by jumping to a higher orbit, one of the more energetic stationary
states farther away from the nucleus.
Add more energy and the electron
continues jumping to higher orbits.
Cease adding energy—leave the atom
alone—and the electrons jump back to their ground states, like this:
With each jump, each electron emits a photon of characteristic energy.
e
jumps, and so the photon energies, are limited by Planck’s constant.
Subtract
the value of a lower-energy stationary state W 2 from the value of a higher
energy stationary state W 1 and you get exactly the energy of the light as hv.
So here was the physical mechanism of Planck’s cavity radiation.
From this elegant simplification, W 1— W 2 = hv, Bohr was able to derive
the Balmer series.
e lines of the Balmer series turn out to be exactly the
energies of the photons that the hydrogen electron emits when it jumps
down from orbit to orbit to its ground state.
en, sensationally, with the simple formula
(where m is the mass of the electron, e the electron charge and h Planck’s
constant—all fundamental numbers, not arbitrary numbers Bohr made up)
Bohr produced Rydberg’s constant, calculating it within 7 percent of its
experimentally measured value!
“ere is nothing in the world which
impresses a physicist more,” an American physicist comments, “than a
numerical agreement between experiment and theory, and I do not think
that there can ever have been a numerical agreement more impressive than
this one, as I can testify who remember its advent.” 281
“On the constitution of atoms and molecules” was seminally important to
physics.
Besides proposing a useful model of the atom, it demonstrated that
events that take place on the atomic scale are quantized: that just as matter
exists as atoms and particles in a state of essential graininess, so also does
process.
Process is discontinuous and the “granule” of process—of electron
motions within the atom, for example—is Planck’s constant.
e older
mechanistic physics was therefore imprecise; though a good approximation
that worked for large-scale events, it failed to account for atomic subtleties.
Bohr was happy to force this confrontation between the old physics and
the new.
He felt that it would be fruitful for physics.
Because original work is
inherently rebellious, his paper was not only an examination of the physical
world but also a political document.
It proposed, in a sense, to begin a
reform movement in physics: to limit claims and clear up epistemological
fallacies.
Mechanistic physics had become authoritarian.
It had outreached
itself to claim universal application, to claim that the universe and
everything in it is rigidly governed by mechanistic cause and effect.
at was
Haeckelism carried to a cold extreme.
It stifled Niels Bohr as biological
Haeckelism had stifled Christian Bohr and as a similar authoritarianism in
philosophy and in bourgeois Christianity had stifled Søren Kierkegaard.
When Rutherford saw Bohr’s Part I paper, for example, he immediately
found a problem.
“ere appears to me one grave difficulty in your
hypothesis,” he wrote Bohr on March 20, “which I have no doubt you fully
realise, namely, how does an electron decide what frequency it is going to
vibrate at when it passes from one stationary state to the other?
It seems to
me that you would have to assume that the electron knows beforehand
where it is going to stop.” 282 Einstein showed in 1917 that the physical
answer to Rutherford’s question is statistical—any frequency is possible, and
the ones that turn up happen to have the best odds.
But Bohr answered the
question in a later lecture in more philosophical and even anthropomorphic
terms: “Every change in the state of an atom should be regarded as an
individual process, incapable of more detailed description, by which the
atom goes over from one so-called stationary state to another....
We are
here so far removed from a causal description that an atom in a stationary
state may in general even be said to possess a free choice between various
possible transitions.” 283 e “catchwords” here, as Harald Høffding might say, are individual and free choice.
Bohr means the changes of state within
individual atoms are not predictable; the catchwords color that physical
limitation with personal emotion.
In fact the 1913 paper was deeply important emotionally to Bohr.
It is a
remarkable example of how science works and of the sense of personal
authentication that scientific discovery can bestow.
Bohr’s emotional
preoccupations sensitized him to see previously unperceived regularities in
the natural world.
e parallels between his early psychological concerns
and his interpretation of atomic processes are uncanny, so much so that
without the great predictive ability of the paper its assumptions would seem
totally arbitrary.
Whether or not the will is free, for example, was a question that Bohr took
seriously.
To identify a kind of freedom of choice within the atom itself was a
triumph for his carefully assembled structure of beliefs.
e separate,
distinct electron orbits that Bohr called stationary states recall Kierkegaard’s
stages.
ey also recall Bohr’s attempt to redefine the problem of free will by
invoking separate, distinct Riemann surfaces.
And as Kierkegaard’s stages
are discontinuous, negotiable only by leaps of faith, so do Bohr’s electrons
leap discontinuously from orbit to orbit.
Bohr insisted as one of the two
“principal assumptions” of his paper that the electron’s whereabouts between
orbits cannot be calculated or even visualized.284 Before and aer are
completely discontinuous.
In that sense, each stationary state of the electron
is complete and unique, and in that wholeness is stability.
By contrast, the
continuous process predicted by classical mechanics, which Bohr apparently
associated with the licentiate’s endless ratiocination, tears the atom apart or
spirals it into radiative collapse.
Bohr may have found his way through his youthful emotional crisis in
part by calling up his childhood gi of literal-mindedness.
He famously
insisted on anchoring physics in fact and refused to carry argument beyond
physical evidence.
He was never a system-builder.
“Bohr characteristically
avoids such a word as ‘principle,’ ” says Rosenfeld; “he prefers to speak of
‘point of view’ or, better still, ‘argument,’ i.e.
line of reasoning; likewise, he
rarely mentions the ‘laws of nature,’ but rather refers to ‘regularities of the
phenomena.’ ”285 Bohr was not displaying false humility with his choice of
terms; he was reminding himself and his colleagues that physics is not a
grand philosophical system of authoritarian command but simply a way, in
his favorite phrase, of “asking questions of Nature.” 286 He apologized
similarly for his tentative, rambling habit of speech: “I try not to speak more
clearly than I think.” 287
“He points out,” Rosenfeld adds, “that the idealized concepts we use in
science must ultimately derive from common experiences of daily life which
cannot themselves be further analysed; therefore, whenever any two such
idealizations turn out to be incompatible, this can only mean that some
mutual limitation is imposed upon their validity.” 288 Bohr had found a
solution to the spiraling flights of doubt by stepping out of what Kierkegaard
called “the fairyland of the imagination” and back into the real world.
289 In
the real world material objects endure; their atoms cannot, then, ordinarily
be unstable.
In the real world cause and effect sometimes seem to limit our
freedom, but at other times we know we choose.
In the real world it is
meaningless to doubt existence; the doubt itself demonstrates the existence
of the doubter.
Much of the difficulty was language, that slippery medium in
which Bohr saw us inextricably suspended.
“It is wrong,” he told his
colleagues repeatedly, “to think that the task of physics is to find out how
nature is” —which is the territory classical physics had claimed for itself.
“Physics concerns what we can say about nature.” 290
Later Bohr would develop far more elaborately the idea of mutual
limitations as a guide to greater understanding.
It would supply a deep
philosophical basis for his statecra as well as for his physics.
In 1913 he first
demonstrated its resolving power.
“It was clear,” he remembered at the end
of his life, “and that was the point about the Rutherford atom, that we had
something from which we could not proceed at all in any other way than by
radical change.
And that was the reason then that [I] took it up so
seriously.” 291
4
The Long Grave Already Dug
Otto Hahn cherished the day the Kaiser came to visit.
e official dedication
of the first two Kaiser Wilhelm Institutes, one for chemistry, one for physical
chemistry, on October 23, 1912—Bohr in Copenhagen was approaching his
quantized atom—was a wet day in the suburb of Dahlem southwest of
Berlin.
292, 293 e Kaiser, Wilhelm II, Victoria’s eldest grandson, wore a raincloak to protect his uniform, the dark collar of his greatcoat turned out
over the lighter shawl of the cloak.
e officials who walked the requisite
paces behind him, his scholarly friend Adolf von Harnack and the
distinguished chemist Emil Fischer foremost among them, made do with
dark coats and top hats; those farther back in the procession who carried
umbrellas kept them furled.
Schoolboys, caps in hand, lined the curbs of the
shining street like soldiers on parade.
ey stood at childish attention, awe
dazing their dreamy faces, as this corpulent middle-aged man with upturned
dark mustaches who believed he ruled them by divine right passed in
review.
ey were thirteen, perhaps fourteen years old.
ey would be
soldiers soon enough.
Officials in the Ministry of Culture had encouraged His Imperial Majesty
to support German science.
He responded by donating land for a research
center on what had been a royal farm.
Industry and government then
lavishly endowed a science foundation, the Kaiser Wilhelm Society, to
operate the proposed institutes, of which there would be seven by 1914.
294
e society began its official life early in 1911 with von Harnack, a
theologian who was the son of a chemist, as its first president.
e imperial
architect, Ernst von Ihne, went briskly to work.
e Kaiser came to Dahlem
to dedicate the first two finished buildings, and the Institute for Chemistry
especially must have pleased him.
It was set back on a broad lawn at the
corner of ielallee and Faradayweg: three stories of cut stone filigreed with
six-paned windows, a steep, gabled slate roof and at the roofline high above
the entrance a classical pediment supported by four Doric columns.
A wing
angled off paralleling the cross street.
Fitted between the main building and
the wing like a hinge, a round tower rose up dramatically four stories high.
Von Ihne had surmounted the tower with a dome.
Apparently the dome was
meant to flatter the Kaiser’s taste.
A sense of humor was not one of Wilhelm
II’s strong points and no doubt it did.
e dome took the form of a giant
Pickelhaube, the comic-opera spiked helmet that the Kaiser and his soldiers
wore.
Leaving Ernest Rutherford in Montreal in 1906 Hahn had moved to
Berlin to work with Emil Fischer at the university.
Fischer was an organic
chemist who knew little about radioactivity, but he understood that the field
was opening to importance and that Hahn was a first-rate man.
He made
room for Hahn in a wood shop in the basement of his laboratories and
arranged Hahn’s appointment as a Privatdozent, which stirred less forward-
looking chemists on the faculty to wonder aloud at the deplorable decline in
standards.
A chemist who claimed to identify new elements with a gold-foil
electroscope must be at least an embarrassment, if not in fact a fraud.
295
Hahn found the university’s physicists more congenial than its chemists
and regularly attended the physics colloquia.
At one colloquium at the
beginning of the autumn term in 1907 he met an Austrian woman, Lise
Meitner, who had just arrived from Vienna.296 Meitner was twenty-nine, one
year older than Hahn.
She had earned her Ph.D.
at the University of Vienna
and had already published two papers on alpha and beta radiation.
Max
Planck’s lectures in theoretical physics had drawn her to Berlin for
postgraduate study.
Hahn was a gymnast, a skier and a mountain climber, boyishly
goodlooking, fond of beer and cigars, with a Rhineland drawl and a warm,
selfdeprecating sense of humor.
He admired attractive women, went out of
his way to cultivate them and stayed friends with a number of them
throughout his happily married life.
Meitner was petite, dark and pretty, if
also morbidly shy.
Hahn befriended her.
When she found she had free time
she decided to experiment.
She needed a collaborator.
So did Hahn.
A
physicist and a radiochemist, they would make a productive team.
ey required a laboratory.
Fischer agreed that Meitner could share the
wood shop on condition that she never show her face in the laboratory
upstairs where the students, all male, worked.297 For two years she observed
the condition strictly; then, with the liberalization of the university, Fischer
relented, allowed women into his classes and Meitner above the basement.
Vienna had been only a little more enlightened.
Meitner’s father, an attorney
—the Meitners were assimilated Austrian Jews, baptized all around—had
insisted that she acquire a teacher’s diploma in French before beginning to
study physics so that she would always be able to support herself.
Only then
could she prepare for university work.
With the diploma out of the way
Meitner crammed eight years of Gymnasium preparation into two.
She was
the second woman ever to earn a Ph.D at Vienna.
Her father subsidized her
research in Berlin until at least 1912, when Max Planck, by now a warm
supporter, appointed her to an assistantship.
“e German Madame Curie,”
Einstein would call her, characteristically lumping the Germanic peoples
together and forgetting her Austrian birth.
“ere was no question,” says Hahn, “of any closer relationship between us
outside the laboratory.
Lise Meitner had had a strict, lady-like upbringing
and was very reserved, even shy.” ey never ate lunch together, never went
for a walk, met only in colloquia and in the wood shop.
“And yet we were
really close friends.
”298 She whistled Brahms and Schumann to him to pass
the long hours taking timed readings of radioactivity to establish identifying
half-lives, and when Rutherford came through Berlin in 1908 on his way
back from the Nobel Prize ceremonies she selflessly accompanied Mary
Rutherford shopping while the two men indulged themselves in long talks.
e close friends moved together to the new institute in 1912 and worked
to prepare an exhibit for the Kaiser.
In his first venture into radiochemistry,
in London before he went to Montreal, Hahn had spied out what he took to
be a new element, radiothorium, that was one hundred thousand times as
radioactive as its modest namesake.
At McGill he found a third substance
intermediate between the other two; he named it “meso thorium” and it was
later identified as an isotope of radium.
Mesothorium compounds glow in
the dark at a different level of faint illumination from radiothorium
compounds.
Hahn thought the difference might amuse his sovereign.
On a
velvet cushion in a little box he mounted an unshielded sample of
mesothorium equivalent in radiation intensity to 300 milligrams of radium.
He presented his potent offering to the Kaiser and asked him to compare it
to “an emanating sample of radiothorium that produced in the dark very
nice luminous moving shapes on [a] screen.” 299 No one warned His Majesty
of the radiation hazard because no safety standards for radiation exposure
had yet been set.
“If I did the same thing today,” Hahn said fiy years later, “I
should find myself in prison.” 300
e mesothorium caused no obvious harm.
e Kaiser passed on to the
second institute, half a block up Faradayweg northwest beyond the angled
wing.
Two senior chemists managed the Chemistry Institute where Hahn
and Meitner worked, but the Institute for Physical Chemistry and
Electrochemistry, to give it its full name, was established specifically for the
man who was its first director, a difficult, inventive German-Jewish chemist
from Breslau named Fritz Haber.
It was a reward of sorts.
A German
industrial foundation paid for it and endowed it because in 1909 Haber had
succeeded in developing a practical method of extracting nitrogen from the
air to make ammonia.
e ammonia would serve for artificial fertilizer,
replacing Germany’s and the world’s principal natural source, sodium nitrate
dug from the bone-dry northern desert of Chile, an expensive and insecure
supply.
More strategically, the Haber process would be invaluable in time of
war to produce nitrates for explosives; Germany had no nitrates of its own.
Kaiser Wilhelm enlarged at the dedication on the dangers of firedamp, the
explosive mixture of methane and other gases that accumulates in mines.
He
urged his chemists to find some early means of detection.
at was a task, he
said, “worthy of the sweat of noble brows.” 301 Haber, noble brow—he shaved
his bullet head, wore round horn-rimmed glasses and a toothbrush
mustache, dressed well, wined and dined in elegance but suffered bitter
marital discord—set out to invent a firedamp whistle that would sound a
different pitch when dangerous gases were present.
With a fine modern
laboratory uncontaminated by old radioactivity Hahn and Meitner went to
work at radiochemistry and the new field of nuclear physics.
e Kaiser
returned from Dahlem to his palace in Berlin, happy to have lent his name
to yet another organ of burgeoning German power.
* * *
In the summer of 1913 Niels Bohr sailed with his young wife to England.
He
followed the second and third parts of his epochal paper, which he had sent
ahead by mail to Rutherford; he wanted to discuss them before releasing
them for publication.
In Manchester he met his friend George de Hevesy
again and some of the other research men.
One he met, probably for the first
time, was Henry Gwyn Jeffreys Moseley, called Harry, an Eton boy and an
Oxford man who had worked for Rutherford as a demonstrator, teaching
undergraduates, since 1910.302 Harry Moseley at twenty-six was poised for
great accomplishment.
He needed only the catalyst of Bohr’s visit to set him
off.Moseley was a loner, “so reserved,” says A.
S.
Russell, “that I could neither
like him nor not like him,” but with the unfortunate habit of allowing no
loose statement of fact to pass unchallenged.303 When he stopped work long
enough to take tea at the laboratory he even managed to inhibit Ernest
Rutherford.
Rutherford’s other “boys” called him “Papa.” Moseley respected
the boisterous laureate but certainly never honored him with any such
intimacy; he rather thought Rutherford played the stage colonial.
Harry came from a distinguished line of scientists.
His great-grandfather
had operated a lunatic asylum with healing enthusiasm but without benefit
of medical license, but his grandfather was chaplain and professor of natural
philosophy and astronomy at King’s College and his father had sailed as a
biologist on the three-year voyage of H.M.S.
Challenger that produced a
fiy-volume pioneering study of the world ocean.
Henry Moseley—Harry
had his father’s first name—won the friendly praise of Charles Darwin for
his one-volume popular account, Notes by a Naturalist on the ‘Challenger’;
Harry in his turn would work with Darwin’s physicist grandson Charles G.
Darwin at Manchester.
If he was reserved to the point of stuffiness he was also indefatigable at
experiment.
He would go all out for fieen hours, well into the night, until
he was exhausted, eat a spartan meal of cheese sometime before dawn, find a
few hours for sleep and breakfast at noon on fruit salad.
He was trim,
carefully dressed and conservative, fond of his sisters and his widowed
mother, to whom he regularly wrote chatty and warmly devoted letters.
Hay
fever threw off his final honors examinations at Oxford; he despised
teaching the Manchester undergraduates—many were foreigners, “Hindoos,
Burmese, Jap, Egyptian and other vile forms of Indian,” and he recoiled from
their “scented dirtiness.” 304 But finally, in the autumn of 1912, Harry found
his great subject.
“Some Germans have recently got wonderful results by passing X rays
through crystals and then photographing them,” he wrote his mother on
October 10.
305 e Germans, at Munich, were directed by Max von Laue.
Von Laue had found that the orderly, repetitive atomic structure of a crystal
produces monochromatic interference patterns from X rays just as the
mirroring, slightly separated inner and outer surfaces of a soap bubble
produce interference patterns of color from white light.
X-ray
crystallography was the discovery that would win von Laue the Nobel Prize.
Moseley and C.
G.
Darwin set out with a will to explore the new field.
ey
acquired the necessary equipment and worked through the winter.
By May
1913 they had advanced to using crystals as spectroscopes and were
finishing up a first solid piece of work.
X rays are energetic light of extremely
short wavelength.
e atomic lattices of crystals spread out their spectra
much as a prism does visible light.
“We find,” Moseley wrote his mother on
May 18, “that an X ray bulb with a platinum target gives out a sharp line
spectrum of five wavelengths....
Tomorrow we search for the spectra of
other elements.
ere is here a whole new branch of spectroscopy, which is
sure to tell one much about the nature of the atom.
”306
en Bohr arrived and the question they discussed was Bohr’s old insight
that the order of the elements in the periodic table ought to follow the
atomic number rather than, as chemists thought, the atomic weight.
(e
atomic number of uranium, for example, is 92; the atomic weight of the
commonest isotope of uranium is 238; a rarer isotope of uranium has an
atomic weight of 235 and the same atomic number.) Harry could look for
regular shis in the wavelengths of X-ray line spectra and prove Bohr’s
contention.
Atomic number would make a place in the periodic table for all
the variant physical forms that had been discovered and that would soon be
named isotopes; atomic number, emphasizing the charge on the nucleus as
the determiner of the number of electrons and hence of the chemistry,
would strongly confirm Rutherford’s nuclear model of the atom; the X-ray
spectral lines would further document Bohr’s quantized electron orbits.
e
work would be Moseley’s alone; Darwin by then had withdrawn to pursue
other interests.
Bohr and the patient Margrethe went on to Cambridge to vacation and
polish Bohr’s paper.
Rutherford le near the end of July with Mary on an
expedition to the idyllic mountains of the Tyrol.
Moseley stayed in
“unbearably hot and stuffy” Manchester, blowing glass.
“Even now near
midnight,” he wrote his mother two days aer Rutherford’s departure, “I
discard coat and waistcoat and work with windows and door open to try to
get some air.
I will come to you as soon as I can get my apparatus to work
before ever I start measurements.
”307 On August 13 he was still at it.
He
wrote his married sister Margery to explain what he was aer:
I want in this way to find the wave-lengths of the X ray spectra of as many
elements as possible, as I believe they will prove much more important
and fundamental than the ordinary light spectra.
e method of finding
the wavelengths is to reflect the X rays which come from a target of the
element investigated [when such a target is bombarded with cathode
rays]....
I have then merely to find at which angles the rays are reflected,
and that gives the wavelengths.
I aim at an accuracy of at least one in a
thousand.308
e Bohrs returned to Copenhagen, the Rutherfords from the Tyrol, and
now it was September and time for the annual meeting of the British
Association, this year in Birmingham.
Bohr had not planned to attend,
especially aer lingering overlong in Cambridge, but Rutherford thought he
should: his quantized atom with its stunning spectral predictions would be
the talk of the conference.
Bohr relented and rushed over.
Birmingham’s
hotels were booked tight.
He slept the first night on a billiard table.
309 en
the resourceful de Hevesy found him a berth in a girls’ college.
“And that
was very, very practical and wonderful,” Bohr remembered aerward,
adding quickly that “the girls were away.” 310
Sir Oliver Lodge, president of the British Association, mentioned Bohr’s
work in his opening address.
Rutherford touted it in meetings.
James Jeans,
the Cambridge mathematical physicist, allowed wittily that “the only
justification at present put forward for these assumptions is the very weighty
one of success.” 311 A Cavendish physicist, Francis W.
Aston, announced that
he had succeeded in separating two different weights of neon by tediously
diffusing a large sample over and over again several thousand times through
pipe clay—“a definite proof,” de Hevesy noted, “that elements of different
atomic weight can have the same chemical properties.” 312 Marie Curie came
across from France, “shy,” says A.
S.
Eve, “retiring, self-possessed and
noble.” 313 She fended off the bulldog British press by praising Rutherford:
“great developments,” she predicted, were “likely to transpire” from his work.
He was “the one man living who promises to confer some inestimable boon
on mankind.” 314
Harald Bohr reported to his brother that autumn that the younger men at
Gottingen “do not dare to believe that [your paper] can be objectively right;
they find the assumptions too ‘bold’ and ‘fantastic.’ ” 315 Against the
continuing skepticism of many European physicists Bohr heard from de
Hevesy that Einstein himself, encountered at a conference in Vienna, had
been deeply impressed.
De Hevesy passed along a similar tale to Rutherford:
Speaking with Einstein on different topics we came to speak on Bohr’s
theory, he told me that he had once similar ideas but he did not dare to
publish them.
“Should Bohr’s theory be right, it is of the greatest
importance.” When I told him about the [recent discovery of spectral lines
where Bohr’s theory had predicted they should appear] the big eyes of
Einstein looked still bigger and he told me “en it is one of the greatest
discoveries.” 316
I felt very happy hearing Einstein saying so.
So did Bohr.
Moseley labored on.
He had trouble at first making sharp photographs of
his X-ray spectra, but once he got the hang of it the results were outstanding.
e important spectral lines shied with absolute regularity as he went up
the periodic table, one step at a time.
He devised a little staircase of strips of
film by matching up the lines.
He wrote to Bohr on November 16: “During
the last fortnight or so I have been getting results which will interest you....
So far I have dealt with the K [spectral line] series from Calcium to Zinc....
e results are exceedingly simple and largely what you would expect....
K
= N − 1, very exactly, N being the atomic number.” He had calcium at 20,
scandium at 21, titanium at 22, vanadium at 23, chromium at 24 and so on
up to zinc at 30.
He concludes that his results “lend great weight to the
general principles which you use, and I am delighted that this is so, as your
theory is having a splendid effect on Physics.
”317 Harry Moseley’s crisp work
gave experimental confirmation of the Bohr-Rutherford atom that was far
more solidly acceptable than Marsden’s and Geiger’s alpha-scattering
experiments.
“Because you see,” Bohr said in his last interview, “actually the
Rutherford work was not taken seriously.
We cannot understand today, but
it was not taken seriously at all....
e great change came from Moseley.
”318
* * *
Otto Hahn was called upon once more to demonstrate his radioactive
preparations.
In the early spring of 1914 the Bayer Dye Works at
Leverkusen, near Cologne in the Rhineland, gave a reception to celebrate the
opening of a large lecture hall.
319 Germany’s chemical industry led the world
and Bayer was the largest chemical company in Germany, with more than
ten thousand employees.
It manufactured some two thousand different
dyestuffs, large tonnages of inorganic chemicals, a range of pharmaceuticals.
e firm’s managing director, Carl Duisberg, a chemist who preferred
industrial management along American lines, had invited the Oberpräsident
of the Rhineland to attend the reception; he then invited Hahn to add a glow
to the proceedings.
Hahn lectured to the dignitaries on radioactivity.
Near the beginning of
the lecture he wrote Duisberg’s name on a sealed photographic plate with a
small glass tube filled with strong mesothorium.
Technicians developed the
plate while he spoke; at the end Hahn projected the radiographic signature
onto a screen to appreciative applause.
e high point of the celebration at the vast 900-acre chemical complex
came in the evening.
“In the evening there was a banquet,” Hahn
remembered with nostalgia; “everything was exquisite.
On each of the little
tables there was a beautiful orchid, brought from Holland by air.” Orchids
delivered by swi biplane might be adequate symbols of German prosperity
and power in 1914, but the managing director wanted to demonstrate
German technological superiority as well, and found exotic statement: “At
many of the tables,” says Hahn, evoking an unrecognizably futuristic past,
“the wine was cooled by means of liquid air in thermos vessels.
”320
* * *
When war broke out Niels and Harald Bohr were hiking in the Austrian
Alps, covering as much as twenty-two miles a day.
“It is impossible to
describe how amazing and wonderful it is,” Niels had written to Margrethe
along the way, “when the fog on the mountains suddenly comes driving
down from all the peaks, initially as quite small clouds, finally to fill the
whole valley.” 321 e brothers had planned to return home August 6; the war
suddenly came driving down like the mountain fog and they rushed across
Germany before the frontiers closed.
In October Bohr would sail with his
wife from neutral Denmark to teach for two years at Manchester.
Rutherford, his boys off to war work, needed help.
Harry Moseley was in Australia with his mother at the beginning of
August, attending the 1914 British Association meeting, in his spare time
searching out the duck-billed platypus and picturesque silver mines.
e
patriotism of the Australians, who immediately began mobilizing, triggered
his own Etonian spirit of loyalty to King and country.
He sailed for England
as soon as he could book passage.
By late October he had gingered up a
reluctant recruiting officer to arrange his commission as a lieutenant in the
Royal Engineers ahead of the waiting list.
* * *
Chaim Weizmann, the tall, sturdy, Russian-born Jewish biochemist who was
Ernest Rutherford’s good friend at Manchester, was a passionate Zionist at a
time when many, including many influential British Jews, believed Zionism
to be at least visionary and naive if not wrongheaded, fanatic, even a
menace.
But if Weizmann was a Zionist he was also deeply admiring of
British democracy, and one of his first acts aer the beginning of the war
was to cut himself off from the international Zionist organization because it
proposed to remain neutral.
Its European leaders hated Czarist Russia,
England’s ally, and so did Weizmann, but unlike them he did not believe that
Germany in cultural and technological superiority would win the war.
He
believed that the Western democracies would emerge victorious and that
Jewish destiny lay with them.
He, his wife and his young son had been en route to a holiday in
Switzerland at the outbreak of the war.
ey worked their way back to Paris,
where he visited the elderly Baron Edmond de Rothschild, financial
mainstay of the pioneering Jewish agricultural settlements in Palestine.
To
Weizmann’s astonishment Rothschild shared his optimism about the
eventual outcome of the war and its possibilities for Jewry.
ough
Weizmann had no official position in the Zionist movement, Rothschild
urged him to seek out and talk to British leaders.
at matched his own inclinations.
His hope of British influence had deep
roots.
He was the third child among fieen of a timber merchant who
assembled ras of logs and floated them down the Vistula to Danzig for
milling and export.
e Weizmanns lived in that impoverished western
region of Russia cordoned off for the Jews known as the Pale of Settlement.
When Chaim was only eleven he had written a letter that prefigured his
work in the war.
“e eleven-year-old boy,” reports his biographer Isaiah
Berlin, “says that the kings and nations of the world are plainly set upon the
ruin of the Jewish nation; the Jews must not let themselves be destroyed;
England alone may help them to return and rise again in their ancient land
of Palestine.” 322
Young Weizmann’s conviction drove him inexorably west.
At eighteen he
floated on one of his father’s ras to West Prussia, worked his way to Berlin
and studied at the Technische Hochschule.
In 1899 he took his Ph.D.
at the
University of Fribourg in Switzerland, then sold a patent to Bayer that
considerably improved his finances.
He moved to England in 1904, a move
he thought “a deliberate and desperate step....
I was in danger of
degenerating into a Lumensch [literally, an “air-man”], one of those well-
meaning, undisciplined and frustrated ‘eternal students.’ ” 323 Chemical
research would save him from that fate; he settled in Manchester under the
sponsorship of William Henry Perkin, Jr., the head of the chemistry
department there, whose father had established the British coal-tar dye
industry by isolating aniline blue, the purple dye aer which the Mauve
Decade was named.
Returning to Manchester from France in late August 1914, Weizmann
found a circular on his desk from the British War Office “inviting every
scientist in possession of any discovery of military value to report it.” He
possessed such a discovery and forthwith offered it to the War Office
“without remuneration.” 324 e War Office chose not to reply.
Weizmann
went on with his research.
At the same time he began the approach to
British leaders that he and Rothschild had discussed that would elaborate
into some two thousand interviews before the end of the war.
Weizmann’s discovery was a bacillus and a process.
e bacillus was
Clostridium acetobutylicum Weizmann, informally called B-Y (“bacillus-
Weizmann”), an anerobic organism that decomposes starch.
He was trying
to develop a process for making synthetic rubber when he found it, on an
ear of corn.
He thought he could make synthetic rubber from isoamyl
alcohol, which is a minor byproduct of alcoholic fermentation.
He went
looking for a bacillus—millions of species and subspecies live in the soil and
on plants—that converted starch to isoamyl alcohol more efficiently than
known strains.
“In the course of this investigation I found a bacterium
which produced considerable amounts of a liquid smelling very much like
isoamyl alcohol.
325 But when I distilled it, it turned out to be a mixture of
acetone and butyl alcohol in very pure form.
Professor Perkins advised me
to pour the stuff down the sink, but I retorted that no pure chemical is
useless or ought to be thrown away.”
at creature of serendipity was B-Y.
Mixed with a mash of cooked corn it
fermented the mash into a solution of water and three solvents—one part
ethyl alcohol, three parts acetone, six parts butyl alcohol (butanol).
e three
solvents could then be separated by straightforward distillation.
Weizmann
tried developing a process for making synthetic rubber from butanol and
succeeded.
In the meantime, in the years just prior to the beginning of the
war, the price of natural rubber fell and the clamor for synthetic rubber
stilled.
Pursuing his efforts toward a Jewish homeland, Weizmann acquired in
Manchester a loyal and influential friend, C.
P.
Scott, the tall, elderly, liberal
editor of the Manchester Guardian.
Among his many connections, Scott was
David Lloyd George’s most intimate political adviser.
Weizmann found
himself having breakfast one Friday morning in January 1915 with the
vigorous little Welshman who was then Chancellor of the Exchequer and
who would become Prime Minister in the middle of the war.
326 Lloyd
George had been raised on the Bible.
He respected the idea of a Jewish
return to Palestine, especially when Weizmann eloquently compared rocky,
mountainous, diminutive Palestine with rocky, mountainous, diminutive
Wales.
Besides Lloyd George, Weizmann was surprised to find interest in
Zionism among such men as Arthur Balfour, the former Prime Minister
who would serve as Foreign Secretary in Lloyd George’s cabinet, and Jan
Christiaan Smuts, the highly respected Boer who joined the British War
Cabinet in 1917 aer serving behind the scenes previously.
“Really
messianic times are upon us,” Weizmann wrote his wife during this period
of early hope.327
Weizmann had cultured B-Y primarily for its butanol.
He happened one
day to tell the chief research chemist of the Scottish branch of the Nobel
explosives company about his fermentation research.
e man was
impressed.
“You know,” he said to Weizmann, “you may have the key to a
very important situation in your hands.
”328 A major industrial explosion
prevented Nobel from developing the process, but the company let the
British government know.
“So it came about,” writes Weizmann, “that one day in March [1915], I
returned from a visit to Paris to find waiting for me a summons to the
British Admiralty.
”329 e Admiralty, of which Winston Churchill, at
fortyone exactly Weizmann’s age, was First Lord, faced a severe shortage of
acetone.
at acrid solvent was a crucial ingredient in the manufacture of
cordite, a propellant used in heavy artillery, including naval guns, that takes
its name from the cordlike form in which it is usually extruded.
e
explosive material that hurled the heavy shells of the British Navy’s big guns
from ship to ship and ship to shore across miles of intervening water was a
mixture of 64 parts nitrocellulose and 30.2 parts nitroglycerin stabilized
with 5 parts petroleum jelly and soened—gelatinized—with 0.8 percent
acetone.
Cordite could not be manufactured without acetone, and without
cordite the guns would need to be extensively rebuilt to accommodate hotter
propellants that would otherwise quickly erode their barrels.
Weizmann agreed to see what he could do.
Shortly he was brought into
the presence of the First Lord.
As Weizmann remembered the experience of
meeting the “brisk, fascinating, charming and energetic” Winston
Churchill:330
Almost his first words were: “Well, Dr.
Weizmann, we need thirty
thousand tons of acetone.
Can you make it?” I was so terrified by this
lordly request that I almost turned tail.
I answered: “So far I have
succeeded in making a few hundred cubic centimeters of acetone at a time
by the fermentation process.
I do my work in a laboratory.
I am not a
technician, I am only a research chemist.
But, if I were somehow able to
produce a ton of acetone, I would be able to multiply that by any factor
you chose.”...
I was given carte blanche by Mr.
Churchill and the
department, and I took upon myself a task which was to tax all my
energies for the next two years.
at was part one of Weizmann’s acetone experience.
Part two came in
early June.
e British War Cabinet had been shuffled in May because of the
enlarging disaster of the Dardanelles campaign at Gallipoli; Herbert
Asquith, the Prime Minister, had required Churchill’s resignation as First
Lord of the Admiralty and replaced him with Arthur Balfour; Lloyd George
had moved from Chancellor of the Exchequer to Minister of Munitions.
Lloyd George thus immediately inherited the acetone problem in the wider
context of Army as well as Navy needs.
Scott of the Manchester Guardian
alerted him to Weizmann’s work and the two men met on June 7.
Weizmann
told him what he had told Churchill previously.
Lloyd George was impressed
and gave him larger carte blanche to scale up his fermentation process.
In six months of experiments at the Nicholson gin factory in Bow,
Weizmann achieved half-ton scale.
e process proved efficient.
It
fermented 37 tons of solvents—about 11 tons of acetone—from 100 tons of
grain.
Weizmann began training industrial chemists while the government
took over six English, Scottish and Irish distilleries to accommodate them.
A
shortage of American corn—German submarines strangled British shipping
in the First War as in the Second—threatened to shut down the operations.
“Horse-chestnuts were plentiful,” notes Lloyd George in his War Memoirs,
“and a national collection of them was organised for the purpose of using
their starch content as a substitute for maize.
”331 Eventually acetone
production was shied to Canada and the United States and back to corn.
“When our difficulties were solved through Dr.
Weizmann’s genius,”
continues Lloyd George, “I said to him: ‘You have rendered great service to
the State, and I should like to ask the Prime Minister to recommend you to
His Majesty for some honour.’ He said, ‘ere is nothing I want for myself.’
‘But is there nothing we can do as a recognition of your valuable assistance
to the country?’ I asked.
He replied: ‘Yes, I would like you to do something
for my people.’...
at was the fount and origin of the famous declaration
about the National Home for Jews in Palestine.
”332
e “famous declaration” came to be called the Balfour Declaration, a
commitment by the British government in the form of a letter from Arthur
Balfour to Baron Edmond de Rothschild to “view with favour the
establishment in Palestine of a national home for the Jewish people” and to
“use their best endeavours to facilitate the achievement of this object.
”333
at document originated far more complexly than in simple payment for
Weizmann’s biochemical services.
Other spokesmen and statesmen were at
work as well and Weizmann’s two thousand interviews need to be counted
in.
Smuts identified the relationship long aer the war when he said that
Weizmann’s “outstanding war work as a scientist had made him known and
famous in high Allied circles, and his voice carried so much the greater
weight in pleading for the Jewish National Home.
”334
But despite these necessary qualifications, Lloyd George’s version of the
story deserves better than the condescension historians usually accord it.
A
letter of one hundred eighteen words signed by the Foreign Secretary
committing His Majesty’s government to a Jewish homeland in Palestine at
some indefinite future time, “it being clearly understood that nothing shall
be done which may prejudice the civil and religious rights of existing non-
Jewish communities in Palestine.” 335 can hardly be counted an unseemly
reward for saving the guns of the British Army and Navy from premature
senility.
Chaim Weizmann’s experience was an early and instructive example
of the power of science in time of war.
Government took note.
So did
science.
* * *
A heavy German artillery bombardment preceded the second battle of Ypres
that began on April 22, 1915.
Ypres was (or had been: it hardly existed
anymore) a modest market town in southeastern Belgium about eight miles
north of the French border and less than thirty miles inland from the French
port of Dunkirk.
Around Ypres spread shell-cratered, soggy downland
dominated by unpromising low hills—the highest of them, Hill 60 on the
military maps, volcanically contested, only 180 feet elevation.
A line of
Allied and, parallel northeastward, of German trenches curved through the
area, emplaced since the previous November.
Before then, the German attacking and the British defending, the two
armies had run a race to the sea.
e Germans had hoped to win the race to
turn the flank of the Allies.
Not yet fully mobilized for war, they even threw
in Ersatz Corps of ill-trained high school and university students to bolster
their numbers and took 135,000 casualties in what the German people came
to call the Kindermord, the murder of the children.
But at the price of 50,000
lives the British held the narrow flank.
e war that was supposed to be
surgically brief—a quick march through Belgium, France’s capitulation,
home by Christmas—turned to a stagnant war of opposing trenches, in the
Ypres salient as everywhere along the battle line from the Channel to the
Alps.
e April 22 bombardment, the beginning of a concerted German attempt
at breakthrough, had driven the Canadians and French Africans holding the
line at Ypres deep into their trenches.
At sunset it lied.
German troops
moved back from the front line along perpendicular communication
trenches, leaving behind only newly trained Pioniere—combat engineers.
A
German rocket signal went up.
336 e Pioniere set to work opening valves.
A
greenish-yellow cloud hissed from nozzles and dried on the wind across
no-man’s-land.
It blanketed the ground, flowed into craters, over the rotting
bodies of the dead, through wide brambles of barbed wire, dried then
across the sandbagged Allied parapets and down the trench walls past the
firesteps, filled the trenches, found dugouts and deep shelters: and men who
breathed it screamed in pain and choked.
It was chlorine gas, caustic and
asphyxiating.
It smelled as chlorine smells and burned as chlorine burns.
Masses of Africans and Canadians stumbled back in retreat.
Other
masses, surprised and utterly uncomprehending, staggered out of their
trenches into no-man’s-land.
Men clawed at their throats, stuffed their
mouths with shirttails or scarves, tore the dirt with their bare hands and
buried their faces in the earth.
ey writhed in agony, ten thousand of them,
serious casualties; and five thousand others died.
Entire divisions abandoned
the line.
Germany achieved perfect surprise.
All the belligerents had agreed under
the Hague Declaration of 1899 Concerning Asphyxiating Gases “to abstain
from the use of projectiles the sole object of which is the diffusion of
asphyxiating or deleterious gases.” 337 None seemed to think tear gas covered
by this declaration, though tear gases are more toxic than chlorine in
sufficient concentration.
e French used tear gas in the form of rifle
grenades as early as August 1914; the Germans used it in artillery shells fired
against the Russians at Bolimow at the end of January 1915 and on the
Western Front first against the British at Nieuport in March.
But the
chlorine attack at Ypres was the first major and deliberate poison-gas attack
of the war.
As later with other weapons of unfamiliar effect, the chlorine terrorized
and bewildered.
Men threw down their rifles and decamped.
Medical
officers at aid stations were suddenly overwhelmed with casualties the cause
of whose injuries was unknown.
Chemists among the men who survived the
attack recognized chlorine quickly enough, however, and knew how easy it
was to neutralize; within a week the women of London had sewn 300,000
pads of muslin-wrapped cotton for soaking in hyposulfite—the first crude
gas masks.338
Even though the German High Command allowed the use of gas at Ypres,
it apparently doubted its tactical value.
It had massed no reserve troops
behind the lines to follow up.
Allied divisions quickly closed the gap.
Nothing came of the attack except agony.
Otto Hahn, a lieutenant in the infantry reserve, helped install the gas
cylinders, 5,730 of them containing 168 tons of chlorine, originally at a
different place in the line.
339, 340 Shovel crews dug them into the forward walls of the trenches at firestep level and sandbagged them thickly to protect
them from shellfire.
To work them you connected lead pipe to their valves,
ran the pipe over the parapet into no-man’s-land, waited for a rocket to
signal a start and opened the valves for a predetermined time.
Chlorine boils
at—28.5 ° F unpressurized; it boiled out eagerly when released.
But the
prevailing winds had been wrong where Hahn’s team of Pioniere first
installed the chlorine cylinders.
By the time the High Command decided to
remove them to Ypres along a four-mile front where the wind blew more
favorably, Hahn had been sent off to investigate gas-attack conditions in the
Champagne.
In January he was ordered to German-occupied Brussels to see Fritz
Haber.
Haber had just been promoted from reserve sergeant major to
captain, an unprecedented leap in rank in the aristocratic Germany Army.
He needed the rank, he told Hahn, to accomplish his new work.
“Haber
informed me that his job was to set up a special unit for gas-warfare.” 341 It
seems that Hahn was shocked.
Haber offered reasons.
ey were reasons
that would be heard again in time of war:
He explained to me that the Western fronts, which were all bogged down,
could be got moving again only by means of new weapons.
One of the
weapons contemplated was poison gas....
When I objected that this was
a mode of warfare violating the Hague Convention he said that the French
had already started it—though not to much effect—by using rifle-
ammunition filled with gas.
Besides, it was a way of saving countless lives,
if it meant that the war could be brought to an end sooner.
Hahn followed Haber to work on gas warfare.
So did the physicist James
Franck, head of the physics department at Haber’s institute, who, like Haber
and Hahn, would later win the Nobel Prize.
342 So did a crowd of industrial
chemists employed by I.G.
Farben, a cartel of eight chemical companies
assembled in wartime by the energetic Carl Duisberg of Bayer.343 e plant
at Leverkusen with the new lecture hall turned up hundreds of known toxic
substances, many of them dye precursors and intermediates, and sent them
off to the Kaiser Wilhelm Institute for Physical Chemistry and
Electrochemistry for study.
Berlin acquired depots for gas storage and a
school where Hahn instructed in gas defense.
He also directed gas attacks.
In Galicia on the Eastern Front in mid-June
1915, “the wind was favourable and we discharged a very poisonous gas, a
mixture of chlorine and phosgene, against the [Russian] enemy lines....344
Not a single shot was fired....
e attack was a complete success.
”345
Because of its massive chemical industry, which supplied the world before
the war, Germany was far ahead of the Allies in the production of chemicals
for gas warfare.
Early in the war the British had even been reduced to buying
German dyestuffs (not for gas, for dyeing) through neutral countries; when
the Germans discovered the subterfuge they proposed, with what
compounding of cynicism and labored Teutonic humor the record does not
reveal, to trade dyestuffs for scarce rubber and cotton.
346 But France and
Britain went immediately to work.
By the end of the war at least 200,000
tons of chemical warfare agents had been manufactured and used, half by
Germany, half by the several Allies together.
Abrogating the Hague Convention opened an array of new ecological
niches, so to speak, in weaponry.
Types of gas and means of delivery then
proceeded to diversify like Darwin’s finches.
Germany introduced phosgene
next aer chlorine, mixing it with chlorine for cloud-gas attacks like Hahn’s
because of its slow rate of evaporation.
347 e French retaliated in early 1916
with phosgene artillery shells.
Phosgene then became a staple of the war,
dispensed from cylinders, artillery shells, trench mortars, canisters fired
from mortarlike “projectors” and bombs.
It smelled like new-mown hay but
it was by far the most toxic gas used, ten times as toxic as chlorine, fatal in
ten minutes at a concentration of half a milligram per liter of air.
At higher
concentrations one or two breaths killed in a matter of hours.
Phosgene—
carbonyl chloride—hydrolyzed to hydrochloric acid in contact with water;
that was its action in the water-saturated air deep in the delicate bubbled
tissue of the human lung.
It caused more than 80 percent of the war’s gas
fatalities.
Chlorpicrin—the British called it vomiting gas, the Germans called it Klop
—a vicious compound of picric acid and bleaching powder, came along
next.
348 German engineers used it against Russian soldiers in August 1916.
Its special virtue was its chemical inertness.
It did not react with the several
neutralizing chemicals packed in gas-mask canisters; only the modest layer
of activated charcoal in the canisters removed it from the air by adsorption.
So a high concentration could saturate the charcoal and get through.
It
worked like tear gas but induced nausea, vomiting and diarrhea as well.
Men
raised their masks to vomit; if the Klop had been mixed with phosgene, as it
frequently was, they might then be lethally exposed.
Chlorpicrin’s other
advantage was that it was simple and cheap to make.
e most horrible gas of the war, the gas that started a previously
complacent United States developing a chemical-warfare capacity of its own,
was dichlorethyl sulfide, known for its horseradish- or mustard-like smell as
mustard gas.349 e Germans first used it on the night of July 17, 1917, in an
artillery bombardment against the British at Ypres.
e attack came as a
complete surprise and caused thousands of casualties.
Defense in the form
of effective masks and efficient gas discipline had caught up with offense by
the summer of 1917; Germany introduced mustard gas to break the
deadlock, just as it had introduced chlorine before.
Shells marked with
yellow crosses rained down on the men at Ypres.
At first they experienced
not much more than sneezing and many put away their masks.
en they
began vomiting.
eir skin reddened and began to blister.
eir eyelids
inflamed and swelled shut.
ey had to be led away blinded to aid stations,
more than fourteen thousand of them over the next three weeks.
ough the gas smelled like mustard in dense concentrations, in low
concentrations, still extremely toxic, it was hardly noticeable.
It persisted for
days and even weeks in the field.
A gas mask alone was no longer sufficient
protection.
Mustard dissolved rubber and leather; it soaked through
multiple layers of cloth.
One man might bring enough back to a dugout on
the sole of his boot to blind temporarily an entire nest of his mates.
Its odor
could also be disguised with other gases.
e Germans sometimes chose to
disguise mustard with xylyl bromide, a tear gas that smells like lilac, and so
it came to pass in the wartime spring that men ran in terror from a breeze
scented with blossoming lilac shrubs.
ese are not nearly all the gases and poisons developed in the boisterous,
vicious laboratory of the Great War.
ere were sneezing gases and arsenic
powders and a dozen tear gases and every combination.
e French loaded
artillery shells with cyanide—to no point except hatred, as it turned out,
because the resulting vapors were lighter than air and immediately loed
away.
By 1918 a typical artillery barrage locomoting east or west over the
front lines counted nearly as many gas shells as high-explosive.
350 Germany,
always logical at war to the point of inhumanity, blamed the French and
courted a succession of increasingly desperate breakthroughs.
e chemists,
like bargain hunters, imagined they were spending a pittance of tens of
thousands of lives to save a purseful more.
Britain reacted with moral
outrage but capitulated in the name of parity.
It was more than Fritz Haber’s wife could bear.
Clara Immerwahr had
been Haber’s childhood sweetheart.
She was the first woman to win a
doctorate in chemistry from the University of Breslau.
Aer she married
Haber and bore him a son, a neglected housewife with a child to raise, she
withdrew progressively from science and into depression.
Her husband’s
work with poison gas triggered even more desperate melancholy.
“She began
to regard poison gas not only as a perversion of science but also as a sign of
barbarism,” a Haber biographer explains.
“It brought back the tortures men
said they had forgotten long ago.
It degraded and corrupted the discipline
[i.e., chemistry] which had opened new vistas of life.
”351 She asked, argued,
finally adamantly demanded that her husband abandon gas work.
Haber
told her what he had told Hahn, adding for good measure, patriot that he
was, that a scientist belongs to the world in times of peace but to his country
in times of war.352 en he stormed out to supervise a gas attack on the
Eastern Front.
Dr.
Clara Immerwahr Haber committed suicide the same
night.
* * *
e Allied campaign at Gallipoli began on April 25, 1915.
e rough,
southward-descending Gallipoli Peninsula looked westward toward the
Aegean; eastward, across the narrow strait known as the Dardanelles—to the
ancients and to Lord Byron, the Hellespont—it faced Turkish Asia.
Capture
the peninsula; control the Dardanelles, then the Sea of Marmara above, then
the narrow Bosporus Strait that divides Europe from Asia, then
Constantinople, and you might control the Black Sea, into which the
Danube drains—a vast flanking movement against the Central Powers.
Such
were the ambitions of the War Cabinet, chivvied by Winston Churchill, for
the Dardanelles campaign.
e Turks, whose land it was, backed by the
Germans, opposed the operation with machine guns and howitzers.
One Australian, one New Zealand, one French colonial and two British
divisions landed at Gallipoli to establish narrow beachheads.
e water of
one beachhead bay churned as white at first as a rapid, the Turks pouring
down ten thousand rounds a minute from the steep cliffs above; then it
bloomed thick and red with blood.
Geography, error and six Turkish
divisions under a skillful German commander forestalled any effective
advance.
By early May, when a British Gurkha and a French division arrived
to replace the Allied depletions, both sides had chiseled trenches in the
stony ground.
e standoff persisted into summer.
Sir Ian Hamilton, the Allied
commander, Corfu-born, literary, with a Boer-stiffened right arm and the
best of intentions, appealed for reinforcements.
e War Cabinet had
reorganized itself and expelled Churchill; it assented with reluctance to
Hamilton’s appeal and shipped out five divisions more.
Harry Moseley shipped out among them.
He was a signaling officer now,
38th Brigade, 13th Infantry Division, one of Lord Kitchener’s New Army
batches made up of dedicated but inexperienced civilian volunteers.
At
Gibraltar on June 20 he signaled his mother “Our destination no longer in
doubt.” 353 At Alexandria on June 27 he made his will, leaving everything,
which was £2,200, to the Royal Society strictly “to be applied to the
furtherance of experimental research in Pathology Physics Physiology
Chemistry or other branches of science but not in pure mathematics
astronomy or any branch of science which aims merely at describing
cataloguing or systematizing.” 354
Alexandria was “full of heat flies native troops and Australians” and aer a
week they sailed on to Cape Helles on the southern extremity of the
Gallipoli Peninsula, a relatively secure bay behind the trench lines.355 ere
they could ease into combat in the form of artillery shells lobbed over the
Dardanelles to Europe, as it were, from Turkish batteries in Asia.
If men
were bathing in the bay a lookout on the heights blew a trumpet blast to
announce a round coming in.
Centipedes and sand, Harry dispensing
chlorodyne to his men to cure them of the grim amebic dysentery everyone
caught from the beaches, Harry in silk pajamas sharing out the glorious
Tiptree blackberry jam his mother sent.
“e one real interest in life is the
flies,” he wrote her.
“No mosquitoes, but flies by day and flies by night, flies
in the water, flies in the food.
”356
Toward the end of July the divisions crossed to Lemnos to stage for the
reinforcing invasion.
at was to divide the peninsula, gain the heights and
outflank the Turkish lines toward Helles.
Hamilton secreted twenty
thousand men by the dark of the moon into the crowded trenches at a beach
called Anzac halfway up the peninsula and the Turks were none the wiser.
e remainder, some seventeen thousand New Army men, came ashore on
the night of August 6, 1915, at Sulva Bay north of Anzac, to very little
opposition.
When the Turks learned of the invasion they moved new divisions down
the peninsula by forced march.
e objective of the 38th Brigade, what was
le of it toward the end, aer days and nights of continuous marching and
fighting, was an 850-foot hill, Chanuk Bair, inland a mile and a half from
Anzac.
To the west of Chanuk Bair and lower down was another hill with a
patch of cultivated ground: the Farm.
Moseley’s column, commanded by
Brigadier A.
H.
Baldwin, struggling up an imprisoning defile a yard wide
and six hundred feet deep, found its way blocked by a descending train of
mules loaded with ammunition.
at was scabby passage and the brigadier
in a fury of frustration led off north toward the Farm “over ghastly country
in the pitch dark,” says the brigade machine gunner, the men “falling
headlong down holes and climbing up steep and slippery inclines.
”357 But they reached the Farm.
Baldwin’s force then held the far le flank of the line of five thousand
British, Australians and New Zealanders precariously dug into the slopes
below the heights of Chanuk Bair, which the Turks still commanded from
trenches.
e Turkish reinforcements arrived at night and crowded into the Chanuk
trenches, thirty thousand strong.
ey launched their assault at dawn on
August 10 with the sun breaking blindingly at their backs.
John Masefield,
the British poet, was there and lived to report: “ey came on in a
monstrous mass, packed shoulder to shoulder, in some places eight deep, in
others three or four deep.” On the le flank “the Turks got fairly in among
our men with a weight which bore all before it, and what followed was a
long succession of British rallies to a tussle body to body, with knives and
stones and teeth, a fight of wild beasts in the ruined cornfields of e
Farm.
”358 Harry Moseley, in the front line, lost that fight.
When he heard of Moseley’s death, the American physicist Robert A.
Millikan wrote in public eulogy that his loss alone made the war “one of the
most hideous and most irreparable crimes in history.” 359
* * *
Six miles below Dover down the chalk southeastern coast of England the old
resort and harbor town of Folkestone fills a small valley which opens steeply
to the strait.360 Hills shelter the town to the north; the chalk cliff west
sustains a broad municipal promenade of lawns and flower beds.
e harbor,
where Allied soldiers embarked in great numbers for France, offers the
refuge of a deep-water pier a third of a mile long with berths for eight
steamers.
e town remembers William Harvey, the seventeenth-century
physician who discovered the circulation of the blood, as its most
distinguished native son.
At Folkestone on a sunny, warm Friday aernoon, May 25, 1917,
housewives came out in crowds to shop for the Whitsun weekend.
A few
miles away at Shorncliffe camp, Canadian troops mustered on the parade
ground.
ere was bustle and enthusiasm in town and camp alike.
It was
payday.
Without warning the shops and streets exploded.
A line of waiting
housewives crumpled outside a greengrocer’s.
A wine merchant returned to
the front of his shop to find his only customer decapitated.
Blast felled
passersby in a narrow passage between two old buildings.
Horses slumped
dead between the shas of carriages.
Finely shattered glass suddenly iced a
section of street, a conservatory shed its windows, a crater obliterated a
tennis court.
Fires bloomed from damaged stores.
Only aer the first explosions did the people of Folkestone notice the
sound of engines beating the air.
ey hardly understood what they heard.
ey screamed “Zepps!
Zepps!” for until then Zeppelin dirigibles had been
the only mechanism of air attack they knew.
“I saw two aeroplanes,” a
clergyman remembered who ran outside amid the clamor, “not Zeppelins,
emerging from the disc of the sun almost overhead.
en four more, or five,
in a line and others, all light bright silver insects hovering against the blue of
the sky....
ere was about a score in all, and we were charmed with the
beauty of the sight.
”361 Charmed because aircra of any kind were new to
the British sky and these were white and large.
e results were less
charming: 95 killed, 195 injured.
e parade ground at Shorncliffe camp was
damaged but no one was hurt.
Folkestone was the little Guernica of the Great War.
German Gotha
bombers—oversized biplanes—had attacked England for the first time,
bringing with them the burgeoning concept of strategic bombing.
e
England Squadron had been headed for London but had met a solid wall of
clouds inland from Gravesend.
Twenty-one aircra turned south then and
searched for alternative targets.
Folkestone and its nearby army camp
answered the need.
A Zeppelin bombed Antwerp early in the war as the Germans pushed
through Belgium.
Churchill sent Navy fighters to bomb Zeppelin hangars at
Düsseldorf.
Gothas bombed Salonika and a British squadron bombed the
fortress town of Maidos in the Dardanelles during the campaign for
Gallipoli.
But the Gothas that attacked Folkestone in 1917 began the first
effective and sustained campaign of strategic civilian bombardment.
It fitted
Prussian military strategist Karl von Clausewitz’s doctrine of total war in
much the same way that submarine attack did, carrying fear and horror
directly to the enemy to weaken his will to resist.
“You must not suppose
that we set out to kill women and children,” a captured Zeppelin
commander told the British authorities, another rationalization that would
echo.362 “We have higher military aims.
You would not find one officer in
the German Army or Navy who would go to war to kill women and
children.
Such things happen accidentally in war.”
At first the Kaiser, thinking of royal relatives and historic buildings, kept
London off the bombing list.
His naval staff pressed him to relent, which he
did by stages, first allowing the docks to be bombed from naval airships,
then reluctantly enlarging permission westward across the city.
But the
hydrogen-filled airships of Count Ferdinand von Zeppelin were vulnerable
to incendiary bullets; when British pilots learned to fire them the stage was
set for the bombers.
ey came on in irregular numbers, dependent in those later years of the
war not only on the vagaries of weather but also on the vagaries, enforced by
the British blockade, of substandard engine parts and inferior fuel.
A
squadron flew against London by daylight on June 13, nineteen days aer
Folkestone, dropped almost 10,000 pounds of bombs and caused the most
numerous civilian bombing casualties of the war, 432 injured and 162 killed,
including sixteen horribly mangled children in the basement of a nursery
school.
London was nearly defenseless and at first the military saw no reason
to change that naked condition; the War Minister, the Earl of Derby, told the
House of Lords that the bombing was without military significance because
not a single soldier had been killed.
So the Gothas continued their attacks.
ey crossed the Channel from
bases in Belgium three times in July, twice in August, and averaged two raids
a month through the autumn and winter and spring for a total of twenty-
seven in all, first by day and then increasingly, as the British improved their
home defenses, by night.
ey dropped almost a quarter of a million pounds
of bombs, killing 835 people, injuring 1,972 more.
Lloyd George, by then Prime Minister, appealed to the brilliant, reliable
Smuts to develop an air program, including a system of home defense.
Early-warning mechanisms were devised: oversized binaural gramophone
horns connected by stethoscope to keen blind listeners; sound-focusing
cavities carved into sea cliffs that could pick up the wong-wong of Gotha
engines twenty miles out to sea.
Barrage balloons raised aprons of steel cable
that girdled London’s airspace; enormous white arrows mounted on the
ground on pivots guided the radioless defenders in their Sopwith Camels
and Pups toward the invading German bombers.
e completed defense
system around London was primitive but effective and it needed only
technological improvement to ready it for the next war.
At the same time the Germans explored strategic offense.
ey extended
the range of their Gothas with extra fuel tanks.
When daylight bombing
became too risky they learned to fly and bomb at night, navigating by the
stars.
ey produced a behemoth new four-engine bomber, the Giant, a
biplane with a wingspan of 138 feet, unmatched until the advent of the
American B-29 Superfortress more than two decades later.
Its effective range
approached 300 miles.
A Giant dropped the largest bomb of the war on
London on February 16, 1918, a 2,000-pounder that was thirteen feet long; it
exploded on the grounds of the Royal Hospital in Chelsea.
As they came to
understand strategic bombing, the Germans turned from high explosives to
incendiaries, reasoning presciently that fires might cause more damage by
spreading and coalescing than any amount of explosives alone.
By 1918 they
had developed a ten-pound incendiary bomb of almost pure magnesium,
the Elektron, that burned at between 2000° and 3000° and that water could
not dowse.
Only hope of a negotiated peace restrained Germany from
attempting major incendiary raids on London in the final months of the war.
e Germans bombed to establish “a basis for peace” by destroying “the
morale of the English people” and paralyzing their “will to fight.” 363 ey
succeeded in making the British mad enough to think strategic bombing
through.
“e day may not be far off,” Smuts wrote in his report to Lloyd
George, “when aerial operations with their devastation of enemy lands and
destruction of industrial and populous centres on a vast scale may become
the principal operations of the war, to which the older forms of military and
naval operations may become secondary and subordinate.
”364
* * *
e United States Army was slow to respond to gas warfare because it
assumed that masks would adequately protect U.S.
troops.
e civilian
Department of the Interior, which had experience dealing with poison gases
in mines, therefore took the lead in chemical warfare studies.
e Army
quickly changed its mind when the Germans introduced mustard gas in July
1917.
Research contracts for poison-gas development went out to Cornell,
Johns Hopkins, Harvard, MIT, Princeton, Yale and other universities.365
With what a British observer could now call “the great importance attached
in America to this branch of warfare,” Army Ordnance began construction
in November 1917 of a vast war-gas arsenal at Edgewood, Maryland, on
waste and marshy land.366 , 367
e plant, which cost $35.5 million—a complex of 15 miles of roads, 36
miles of railroad track, waterworks and power plants and 550 buildings for
the manufacture of chlorine, phosgene, chlorpicrin, sulfur chloride and
mustard gas—was completed in less than a year.
Ten thousand military and
civilian workers staffed it.
By the end of the war it was capable of filling 1.1
million 75-mm gas shells a month as well as several million other sizes and
types of shells, grenades, mortar bombs and projector drums.
“Had the war
lasted longer,” the British observer notes, “there can be no doubt that this
centre of production would have represented one of the most important
contributions by America to the world war.” 368
* * *
Gas in any case was far less efficient at maiming and killing men than were
artillery and machine-gun fire.
Of a total of some 21 million battle casualties
gas caused perhaps 5 percent, about 1 million.
It killed at least 30,000 men,
but at least 9 million died overall.
Gas may have evoked special horror
because it was unfamiliar and chemical rather than familiar and mechanical
in its effects.
e machine gun forced the opposing armies into trenches; artillery
carried the violence over the parapets once they were there.
So the general
staffs learned to calculate that they would lose 500,000 men in a six-month
offensive or 300,000 men in six months of “ordinary” trench warfare.369 e
British alone fired off more than 170 million artillery rounds, more than 5
million tons, in the course of the war.
370 e shells, if they were not loaded
with shrapnel in the first place, were designed to fragment when they
exploded on impact; they produced by far the most horrible mutilations and
dismemberings of the war, faces torn away, genitals torn away, a flying debris
of arms and legs and heads, human flesh so pulped into the earth that the
filling of sandbags with that earth was a repulsive punishment.
Men cried
out against the monstrousness on all sides.
e machine gun was less mutilating but far more efficient, the basic
slaughtering tool of the war.
“Concentrated essence of infantry,” a military
theorist daintily labeled it.371 Against the criminally stubborn conviction of
the professional officer corps that courage, élan and naked steel must carry
the day the machine gun was the ultimate argument.
“I go forward,” a British
soldier writes of his experience in an attacking line of troops, “...
up and
down across ground like a huge ruined honeycomb, and my wave melts
away, and the second wave comes up, and also melts away, and then the
third wave merges into the ruins of the first and second, and aer a while the
fourth blunders into the remnants of the others.” 372 He was describing the
Battle of the Somme, on July 1, 1916, when at least 21,000 men died in the
first hour, possibly in the first few minutes, and 60,000 the first day.
373
Americans invented the machine gun: Hiram Stevens Maxim, a Yankee
from Maine; Colonel Isaac Lewis, a West Pointer, director of the U.S.
Army
coast artillery school; William J.
Browning, a gunmaker and businessman;
and their predecessor Richard Jordan Gatling, who correctly located the
machine gun among automated systems.
“It bears the same relation to other
firearms,” Gatling noted, “that McCormack’s Reaper does to the sickle, or the
sewing machine to the common needle.
”374 e military historian John
Keegan writes:
For the most important thing about a machine-gun is that it is a machine,
and one of quite an advanced type, similar in some respects to a high-
precision lathe, in others to an automatic press.
Like a lathe, it requires to
be set up, so that it will operate within desired and predetermined limits;
this was done on the Maxim gun...
by adjusting the angle of the barrel
relative to its fixed firing platform, and tightening or loosening its
traversing screw.
en, like an automatic press, it would, when actuated
by a simple trigger, begin and continue to perform its functions with a
minimum of human attention, supplying its own power and only
requiring a steady supply of raw material and a little routine maintenance
to operate efficiently throughout a working shi.
375
e machine gun mechanized war.
Artillery and gas mechanized war.
ey were the hardware of the war, the tools.
But they were only proximately
the mechanism of the slaughter.
e ultimate mechanism was a method of
organization—anachronistically speaking, a soware package.
376 “e basic
lever,” the writer Gil Elliot comments, “was the conscription law, which made
vast numbers of men available for military service.377 e civil machinery
which ensured the carrying out of this law, and the military organization
which turned numbers of men into battalions and divisions, were each
founded on a bureaucracy.
e production of resources, in particular guns
and ammunition, was a matter for civil organization.
e movement of men
and resources to the front, and the trench system of defence, were military
concerns.” Each interlocking system was logical in itself and each system
could be rationalized by those who worked it and moved through it.
us,
Elliot demonstrates, “It is reasonable to obey the law, it is good to organize
well, it is ingenious to devise guns of high technical capacity, it is sensible to
shelter human beings against massive firepower by putting them in
protective trenches.”
What was the purpose of this complex organization?
Officially it was
supposed to save civilization, protect the rights of small democracies,
demonstrate the superiority of Teutonic culture, beat the dirty Hun, beat the
arrogant British, what have you.
But the men caught in the middle came to
glimpse a darker truth.
“e War had become undisguisedly mechanical and
inhuman,” Siegfried Sassoon allows a fictional infantry officer to see.
“What
in earlier days had been dras of volunteers were now droves of victims.
”378
Men on every front independently discovered their victimization.
Awareness intensified as the war dragged on.
In Russia it exploded in
revolution.
In Germany it motivated desertions and surrenders.
Among the
French it led to mutinies in the front lines.
Among the British it fostered
malingering.
Whatever its ostensible purpose, the end result of the complex
organization that was the efficient soware of the Great War was the
manufacture of corpses.
is essentially industrial operation was fantasized
by the generals as a “strategy of attrition.” e British tried to kill Germans,
the Germans tried to kill British and French and so on, a “strategy” so
familiar by now that it almost sounds normal.
It was not normal in Europe
before 1914 and no one in authority expected it to evolve, despite the
pioneering lessons of the American Civil War.
Once the trenches were in
place, the long grave already dug (John Masefield’s bitterly ironic phrase),
then the war stalemated and death-making overwhelmed any rational
response.379 “e war machine,” concludes Elliot, “rooted in law,
organization, production, movement, science, technical ingenuity, with its
product of six thousand deaths a day over a period of 1,500 days, was the
permanent and realistic factor, impervious to fantasy, only slightly altered by
human variation.
”380
No human institution, Elliot stresses, was sufficiently strong to resist the
death machine.
381 A new mechanism, the tank, ended the stalemate.
An old
mechanism, the blockade, choked off the German supply of food and
matériel.
e increasing rebelliousness of the foot soldiers threatened the
security of the bureaucrats.
Or the death machine worked too well, as
against France, and began to run out of raw material.
e Yanks came over
with their sleeves rolled up, an untrenched continent behind them where the
trees were not hung with entrails.
e war putrified to a close.
But the death machine had only sampled a vast new source of raw
material: the civilians behind the lines.
It had not yet evolved equipment
efficient to process them, only big guns and clumsy biplane bombers.
It had
not yet evolved the necessary rationale that old people and women and
children are combatants equally with armed and uniformed young men.
at is why, despite its sickening squalor and brutality, the Great War looks
so innocent to modern eyes.
5
Men from Mars
e first subway on the European continent was dug not in Paris or Berlin
but in Budapest.
Two miles long, completed in 1896, it connected the
thriving Hungarian capital with its northwestern suburbs.
During the same
year the rebuilding of the grand palace of Franz Josef I, in one of his Dual-
Monarchial manifestations King of Hungary, enlarged that structure to 860
rooms.
Across the wide Danube rose a grandiose parliament, its dimensions
measured in acres, six stories of Victorian mansard-roofed masonry
bristling with Neo-Gothic pinnacles set around an elongated Renaissance
dome braced by flying buttresses.
e palace in hilly, quiet Buda confronted
the parliament eastward in flat, bustling Pest.
“Horse-drawn droshkies,”
Hungarian physicist eodor von Kármán remembers of that time, carried
“silk-gowned women and their Hussar counts in red uniforms and furred
hats through the ancient war-scarred hills of Buda.
”382 But “such sights hid
deeper social currents,” von Kármán adds.
From the hills of Buda you could look far beyond Pest onto the great
Hungarian plain, the Carpathian Basin enclosed 250 miles to the east by the
bow of the Carpathian Mountains that the Magyars had crossed to found
Hungary a thousand years before.
Pest expanded within rings of boulevards
on the Viennese model, its offices busy with banking, brokering, lucrative
trade in grain, fruit, wine, beef, leather, timber and industrial proauction
only lately established in a country where more than 96 percent of the
population had lived in settlements of fewer than 20,000 persons as recently
as fiy years before.
Budapest, combining Buda, Óbuda and Pest, had grown
faster than any other city on the Continent in those fiy years, rising from
seventeenth to eighth in rank—almost a million souls.
Now coffeehouses,
“the fountain of illicit trading, adultery, puns, gossip and poetry,” a
Hungarian journalist thought, “the meeting places for the intellectuals and
those opposed to oppression,” enlivened the boulevards; parks and squares
sponsored a cavalry of equestrian bronzes; and peasants visiting for the first
time the Queen City of the Danube gawked suspiciously at blocks of
mansions as fine as any in Europe.383
Economic take-off, the late introduction of a nation rich in agricultural
resources to the organizing mechanisms of capitalism and industrialization,
was responsible for Hungary’s boom.
e operators of those mechanisms, by
virtue of their superior ambition and energy but also by default, were Jews,
who represented about 5 percent of the Hungarian population in 1910.
e
stubbornly rural and militaristic Magyar nobility had managed to keep 33
percent of the Hungarian people illiterate as late as 1918 and wanted nothing
of vulgar commerce except its fruits.384 As a result, by 1904 Jewish families
owned 37.5 percent of Hungary’s arable land; by 1910, although Jews
comprised only 0.1 percent of agricultural laborers and 7.3 percent of
industrial workers, they counted 50.6 percent of Hungary’s lawyers, 53
percent of its commercial businessmen, 59.9 percent of its doctors and 80
percent of its financiers.385 , 386 e only other significant middle class in Hungary was a vast bureaucracy of impoverished Hungarian gentry that
came to vie with the Jewish bourgeoisie for political power.
Caught between
predominantly Jewish socialists and radicals on one side and the entrenched
bureaucracy on the other, both sides hostile, the Jewish commercial elite
allied itself for survival with the old nobility and the monarchy; one measure
of that conservative alliance was the dramatic increase in the early twentieth
century of ennobled Jews.
George de Hevesy’s prosperous maternal grandfather, S.
V.
Schossberger,
became in 1863 the first unconverted Jew ennobled since the Middle Ages,
and in 1895 de Hevesy’s entire family was ennobled.
387 Max Neumann, the
banker father of the brilliant mathematician John von Neumann, was
elevated in 1913.
Von Kármán’s father’s case was exceptional.
Mór Kármán,
the founder of the celebrated Minta school, was an educator rather than a
wealthy businessman.
In the last decades of the nineteenth century he
reorganized the haphazard Hungarian school system along German lines, to
its great improvement—and not incidentally wrested control of education
from the religious institutions that dominated it and passed that control to
the state.
at won him a position at court and the duty of planning the
education of a young archduke, the Emperor’s cousin.
As a result, writes von
Kármán:
One day in August 1907, Franz Joseph called him to the Palace, and said
he wished to reward him for his fine job.
He offered to make my father an
Excellency.388
My father bowed slightly and said: “Imperial Majesty, I am very
flattered.
But I would prefer something which I could hand down to my
children.”
e Emperor nodded his agreement and ordained that my father be
given a place in the hereditary nobility.
To receive a predicate of nobility,
my father had to be landed.
Fortunately he owned a small vineyard near
Budapest, so the Emperor bestowed upon him the predicate “von
Szolloskislak” (small grape).
I have shortened it to von, for even to me, a
Hungarian, the full title is almost unpronounceable.
Jewish family ennoblements in the hundred years prior to 1900 totaled
126; in the short decade and a half between 1900 and the outbreak of the
Great War the insecure conservative alliance bartered 220 more.
389 Some
thousands of men in these 346 families were ultimately involved.
ey were
thus brought into political connection, their power of independent action
siphoned away.
Out of the prospering but vulnerable Hungarian Jewish middle class came
no fewer than seven of the twentieth century’s most exceptional scientists: in
order of birth, eodor von Kármán, George de Hevesy, Michael Polanyi,
Leo Szilard, Eugene Wigner, John von Neumann and Edward Teller.
All
seven le Hungary as young men; all seven proved unusually versatile as
well as talented and made major contributions to science and technology;
two among them, de Hevesy and Wigner, eventually won Nobel Prizes.
e mystery of such a concentration of ability from so remote and
provincial a place has fascinated the community of science.
Recalling that
“galaxy of brilliant Hungarian expatriates,” Otto Frisch remembers that his
friend Fritz Houtermans, a theoretical physicist, proposed the popular
theory that “these people were really visitors from Mars; for them, he said, it
was difficult to speak without an accent that would give them away and
therefore they chose to pretend to be Hungarians whose inability to speak
any language without accent is well known; except Hungarian, and [these]
brilliant men all lived elsewhere.” 390 at was amusing to colleagues and
flattering to the Hungarians, who liked the patina of mystery that
romanticized their pasts.
e truth is harsher: the Hungarians came to live
elsewhere because lack of scientific opportunity and increasing and finally
violent anti-Semitism drove them away.
ey took the lessons they learned
in Hungary with them into the world.
ey all began with talent, variously displayed and remembered.
Von
Kármán at six stunned his parents’ party guests by quickly multiplying
sixfigure numbers in his head.
391 Von Neumann at six joked with his father
in classical Greek and had a truly photographic memory: he could recite
entire chapters of books he had read.392 Edward Teller, like Einstein before
him, was exceptionally late in learning—or choosing—to talk.
393 His
grandfather warned his parents that he might be retarded, but when Teller
finally spoke, at three, he spoke in complete sentences.
Von Neumann too wondered about the mystery of his and his
compatriots’ origins.
His friend and biographer, the Polish mathematician
Stanislaw Ulam, remembers their discussions of the primitive rural foothills
on both sides of the Carpathians, encompassing parts of Hungary,
Czechoslovakia and Poland, populated thickly with impoverished Orthodox
villages.
“Johnny used to say that all the famous Jewish scientists, artists and
writers who emigrated from Hungary around the time of the first World
War came, either directly or indirectly, from those little Carpathian
communities, moving up to Budapest as their material conditions
improved.” 394 Progress, to people of such successful transition, could be a
metaphysical faith.
“As a boy,” writes Teller, “I enjoyed science fiction.
I read
Jules Verne.
His words carried me into an exciting world.
e possibilities of
man’s improvement seemed unlimited.
e achievements of science were
fantastic, and they were good.
”395
Leo Szilard, long before he encountered the novels of H.
G.
Wells, found
another visionary student of the human past and future to admire.
Szilard
thought in maturity that his “addiction to the truth” and his “predilection for
‘Saving the World’ ” were traceable first of all to the stories his mother told
him.
396 But apart from those, he said, “the most serious influence on my life
came from a book which I read when I was ten years old.
It was a Hungarian
classic, taught in the schools, e Tragedy of Man.”
A long dramatic poem in which Adam, Eve and Lucifer are central
characters, e Tragedy of Man was written by an idealistic but disillusioned
young Hungarian nobleman named Imre Madach in the years aer the
failed Hungarian Revolution of 1848.
A modern critic calls the work “the
most dangerously pessimistic poem of the 19th century.” 397 It runs Adam
through history with Lucifer as his guide, rather as the spirits of Christmas
lead Ebenezer Scrooge, enrolling Adam successively as such real historical
personages as Pharaoh, Miltiades, the knight Tancred, Kepler.
Its pessimism
resides in its dramatic strategy.
Lucifer demonstrates to Adam the
pointlessness of man’s faith in progress by staging not imaginary
experiences, as in Faust or Peer Gynt, but real historical events.
Pharaoh
frees his slaves and they revile him for leaving them without a dominating
god; Miltiades returns from Marathon and is attacked by a murderous
crowd of citizens his enemies have bribed; Kepler sells horoscopes to bejewel
his faithless wife.
Adam sensibly concludes that man will never achieve his
ultimate ideals but ought to struggle toward them anyway, a conclusion that
Szilard continued to endorse as late as 1945.
“In [Madach’s] book,” he said
then, “the devil shows Adam the history of mankind, [ending] with the sun
dying down.398 Only a few Eskimos are le and they worry chiefly because
there are too many Eskimos and too few seals [the last scene before Adam
returns to the beginning again].
e thought is that there remains a rather
narrow margin of hope aer you have made your prophecy and it is
pessimistic.”
Szilard’s qualified faith in progress and his liberal political values
ultimately set him apart from his Hungarian peers.
He believed that group
was shaped by the special environment of Budapest at the turn of the
century, “a society where economic security was taken for granted,” as a
historian paraphrases him, and “a high value was placed on intellectual
achievement.” 399 e Minta that Szilard and Teller later attended deeply
gratified von Kármán when he went there in the peaceful 1890s.
“My father
[who founded the school],” he writes, “was a great believer in teaching
everything—Latin, math, and history—by showing its connection with
everyday living.” To begin Latin the students wandered the city copying
down inscriptions from statues and museums; to begin mathematics they
looked up figures for Hungary’s wheat production and made tables and drew
graphs.
“At no time did we memorize rules from a book.
Instead we sought
to develop them ourselves.” 400 What better basic training for a scientist?
Eugene Wigner, small and trim, whose father managed a tannery and who
would become one of the leading theoretical physicists of the twentieth
century, entered the Lutheran Gimnásium in 1913; John von Neumann
followed the next year.
“We had two years of physics courses, the last two
years,” Wigner remembers.
“And it was very interesting.
Our teachers were
just enormously good, but the mathematics teacher was fantastic.
He gave
private classes to Johnny von Neumann.
He gave him private classes because
he realized that this would be a great mathematician.
”401
Von Neumann found a friend in Wigner.
ey walked and talked
mathematics.
Wigner’s mathematical talent was exceptional, but he felt less
than first-rate beside the prodigious banker’s son.
Von Neumann’s brilliance
impressed colleagues throughout his life.
Teller recalls a truncated syllogism
someone proposed to the effect that (a) Johnny can prove anything and (b)
anything Johnny proves is correct.
402 At Princeton, where in 1933 von
Neumann at twenty-nine became the youngest member of the newly
established Institute for Advanced Study, the saying gained currency that the
Hungarian mathematician was indeed a demigod but that he had made a
thorough, detailed study of human beings and could imitate them
perfectly.
403 e story hints at a certain manipulative coldness behind the
mask of bonhomie von Neumann learned to wear, and even Wigner thought
his friendships lacked intimacy.
404 To Wigner he was nevertheless the only
authentic genius of the lot.405
ese earlier memories of Gimnásium days contrast sharply with the
turmoil that Teller experienced.
Part of the difference was personal.
Teller
was bored in first-year math at the Minta and quickly managed to insult his
mathematics teacher, who was also the principal of the school, by improving
on a proof.
e principal took the classroom display unkindly.
“So you are a
genius, Teller?
Well, I don’t like geniuses.” 406 But whatever Teller’s personal
difficulties, he was also confronted directly, as a schoolboy of only eleven
years, with revolution and counterrevolution, with riots and violent
bloodletting, with personal fear.
What had been usually only implicit for the
Martians who preceded him was made explicit before his eyes.
“I think this
was the first time I was deeply impressed by my father,” he told his
biographers.
“He said anti-Semitism was coming.
To me, the idea of anti-
Semitism was new, and the fact that my father was so serious about it
impressed me.” 407
Von Kármán studied mechanical engineering at the University of
Budapest before moving on to Göttingen in 1906; de Hevesy tried Budapest
in 1903 before going to the Technische Hochschule in Berlin in 1904 and on
to work with Fritz Haber and then with Ernest Rutherford; Szilard had
studied at the Technology Institute in Budapest and served in the Army
before the post-Armistice turmoil made him decide to leave.
In contrast,
Wigner, von Neumann and particularly Teller experienced the breakdown of
Hungarian society as adolescents—Teller at the impressionable beginning of
puberty—and at first hand.
“e Revolution arrived as a hurricane,” an eyewitness to the Hungarian
Revolution of October 1918 recalls.
“No one prepared it and no one
arranged it; it broke out by its own irresistible momentum.” 408 But there
were antecedents: a general strike of half a million workers in Budapest and
other Hungarian industrial centers in January 1918; another general strike of
similar magnitude in June.
In the autumn of that year masses of soldiers,
students and workers gathered in Budapest.
is first brief revolution began
with anti-military and nationalistic claims.
By the time the Hungarian
National Council had been formed under Count Mihály Károli (“We can’t
even manage a revolution without a count,” they joked in Budapest), in late
October, there was expectation of real democratic reform: the council issued
a manifesto calling for Hungarian independence, an end to the war, freedom
of the press, a secret ballot and even female suffrage.
e Austro-Hungarian Dual Monarchy collapsed in November.
Austrian
novelist Robert Musil explained that collapse as well as anybody in a dry
epitaph: Es ist passiert (“It sort of happened”).
409 Hungary won a new
government on October 31 and ecstatic crowds filled the streets of Budapest
waving chrysanthemums, which had become the symbol of the revolution,
and cheering the truckloads of soldiers and workers that pushed through.
e victory was not easy aer all.
e revolution hardly extended beyond
Budapest.
e new government was unable to negotiate anything better than
a national dismembering.
e founding of the Republic of Hungary,
proclaimed on November 16, 1918, was shadowed by another founding on
November 20: of the Hungarian Communist Party, by soldiers returning
from Russian camps where they had been radicalized as prisoners of war.
On March 21, 1919, four months aer it began, the Republic of Hungary
bloodlessly metamorphosed into the Hungarian Soviet Republic, its head a
former prisoner of war, disciple of Lenin, journalist, Jew born in the
Carpathians of Transylvania: Béla Kun.
Arthur Koestler, a boy of fourteen
then in Budapest, heard for the first time “the rousing tunes of the
Marseillaise and of the Internationale which, during the hundred days of the
Commune, drowned the music-loving town on the Danube in a fiery,
melodious flood.
”410
It was a little more than a hundred days: 133.
ey were days of confusion,
hope, fear, comic ineptitude and some violence.
Toward the end of the war
von Kármán had returned to Budapest from aeronautics work with the
Austro-Hungarian Air Force, where he had participated in the development
of an early prototype of the helicopter.
De Hevesy had also returned.
Von
Kármán helped reorganize and modernize the university in the brief days of
the Republic and even served as undersecretary for universities during the
Kun regime.
He remembered its naïveté more than its violence: “So far as I
can recall, there was no terrorism in Budapest during the one hundred days
of the Bolsheviks, although I did hear of some sadistic excesses.” 411 Lacking
a qualified physicist, the university hired de Hevesy as a lecturer on
experimental physics during the winter of 1918–19.
Undersecretary von
Kármán appointed him to a newly established professorship of physical
chemistry in March, but de Hevesy found Commune working conditions
unsatisfactory and went off in May to Denmark to visit Bohr.
e two old
friends agreed he would join Bohr’s new institute in Copenhagen as soon as
it was built.
Arthur Koestler remembers that food was scarce, especially if you tried to
buy it with the regime’s ration cards and nearly worthless paper money, but
for some reason the same paper would purchase an abundance of
Commune-sponsored vanilla ice cream, which his family therefore
consumed for breakfast, lunch and dinner.
He mentions this curiosity, he
remarks, “because it was typical of the happy-go-lucky, dilettantish, and
even surrealistic ways in which the Commune was run.” It was, Koestler
thought, “all rather endearing—at least when compared to the lunacy and
savagery which was to descend upon Europe in years to come.
”412
e Hungarian Soviet Republic affected von Neumann and Teller far more
severely.
ey were not admirers like young Koestler nor yet members of the
intellectual elite like de Hevesy and von Kármán.
ey were children of
businessmen—Max Teller was a prosperous attorney.
Max von Neumann
took his family and fled to Vienna.
“We le Hungary,” his son testified many
years later, “very soon aer the Communists seized power....
We le
essentially as soon as it was feasible, which was about 30 or 40 days later, and
we returned about 2 months aer the Communists had been put down.
”413
In Vienna the elder von Neumann joined the group of Hungarian financiers
working with the conservative nobility to overthrow the Commune.
414
Lacking protective wealth, the Tellers stuck it out grimly in Budapest,
living with their fears.
ey made forays into the country to barter with the
peasants for food.
Teller heard of corpses hung from lampposts, though as
with von Kármán’s “sadistic excesses” he witnessed none himself.
415 Faced
with an overcrowded city, the Commune had socialized all housing.
e day
came for the Koestlers as for the Tellers when soldiers charged with
requisitioning bourgeois excesses of floor space and furniture knocked on
their doors.
e Koestlers, who occupied two threadbare rooms in a
boarding house, were allowed to keep what they had, Arthur discovering in
the meantime that working people were interesting and different.
e Tellers
acquired two soldiers who slept on couches in Max Teller’s two office rooms,
connected to the Teller apartment.
416 e soldiers were courteous; they
sometimes shared their food; they urinated on the rubber plant; but because
they searched for hoarded money (which was safely stashed in the cover
linings of Max Teller’s law books) or simply because the Tellers felt generally
insecure, their alien presence terrified.
Yet it was not finally Hungarian communism that frightened Edward
Teller’s parents most.
e leaders of the Commune and many among its
officials were Jewish—necessarily, since the only intelligentsia Hungary had
evolved up to that time was Jewish.
Max Teller warned his son that anti-
Semitism was coming.
Teller’s mother expressed her fears more vividly.
“I
shiver at what my people are doing,” she told her son’s governess in the
heyday of the Commune.417 “When this is over there will be a terrible
revenge.”
In the summer of 1919, as the Commune faltered, eleven-year-old Edward
and his older sister Emmi were packed off to safety at their maternal
grandparents’ home in Rumania.
ey returned in the autumn; by then
Admiral Nicholas Horthy had ridden into Budapest on a white horse behind
a new national army to install a violent fascist regime, the first in Europe.
e Red Terror had come and gone, resulting in some five hundred deaths
by execution.
418 e White Terror of the Horthy regime was of another
order of magnitude: at least 5,000 deaths and many of those sadistic; secret
torture chambers; a selective but unrelenting anti-Semitism that drove tens
of thousands of Jews into exile.
419 A contemporary observer, a socialist
equally biased against either extreme, wrote that he had “no desire whatever
to palliate the brutalities and atrocities of the proletarian dictatorship; its
harshness is not to be denied, even if its terrorists operated more with insults
and threats than with actual deeds.
But the tremendous difference between
the Red and the White Terror is beyond all question.
”420 A friend of the new
regime, Max von Neumann brought his family home.
In 1920 the Horthy regime introduced a numerus clausus law restricting
university admission which required “that the comparative numbers of the
entrants correspond as nearly as possible to the relative population of the
various races or nationalities.” 421 e law, which would limit Jewish
admissions to 5 percent, a drastic reduction, was deliberately anti-Semitic.
ough he was admitted to the University of Budapest and might have
stayed, von Neumann chose instead to leave Hungary at seventeen, in 1921,
for Berlin, where he came under the influence of Fritz Haber and studied
first for a chemical engineering degree, awarded at the Technical Institute of
Zürich in 1925.
A year later he picked up a Ph.D.
summa cum laude in
mathematics at Budapest; in 1927 he became a Privatdozent at the University
of Berlin; in 1929, at twenty-five, he was invited to lecture at Princeton.
He
was professor of mathematics at Princeton by 1931 and accepted lifetime
appointment to the Institute for Advanced Study in 1933.
Von Neumann experienced no personal violence in Hungary, only
upheaval and whatever anxiety his parents communicated.
He nevertheless
felt himself scarred.
His discussion with Stanislaw Ulam went on more
ominously from identifying Carpathian villages as the ultimate places of
origin of Hungary’s talented expatriates.
“It will be le to historians of
science,” Ulam writes, “to discover and explain the conditions which
catalyzed the emergence of so many brilliant individuals from that area....
Johnny used to say that it was a coincidence of some cultural factors which
he could not make precise: an external pressure on the whole society of this
part of Central Europe, a feeling of extreme insecurity in the individuals,
and the necessity to produce the unusual or else face extinction.
”422
Teller was too young to leave Hungary during the worst of the Horthy
years.
is was the adolescent period, as Time magazine paraphrased Teller
later, when Max Teller “dinned into his son two grim lessons: 1) he would
have to emigrate to some more favorable country when he grew up and 2) as
a member of a disliked minority he would have to excel the average just to
stay even.
”423 Teller added a lesson of his own.
“I loved science,” he told an
interviewer once.
“But also it offered a possibility for escaping this doomed
society.” 424 Von Kármán embeds in his autobiography a similarly striking
statement about the place of science in his emotional life.
When the
Hungarian Soviet Republic collapsed he retreated to the home of a wealthy
friend, then found his way back to Germany.
“I was glad to get out of
Hungary,” he writes of his state of mind then.
“I felt I had had enough of
politicians and government upheavals....
Suddenly I was enveloped in the
feeling that only science is lasting.
”425
at science can be a refuge from the world is a conviction common
among men and women who turn to it.
Abraham Pais remarks that Einstein
“once commented that he had sold himself body and soul to science, being
in flight from the ‘I∍ and the ‘we’ to the ‘it.’ ” 426 But science as a means of
escaping from the familiar world of birth and childhood and language when
that world mounts an overwhelming threat—science as a way out, a portable
culture, an international fellowship and the only abiding certitude—must
become a more desperate and therefore a more total dependency.
Chaim
Weizmann gives some measure of that totality in the harsher world of the
Russian Pale when he writes that “the acquisition of knowledge was not for
us so much a normal process of education as the storing up of weapons in an
arsenal by means of which we hoped later to be able to hold our own in a
hostile world.” 427 He remembers painfully that “every division of one’s life
was a watershed.” 428
Teller’s experience in Hungary before he le it in 1926, at seventeen, for
the Technical Institute at Karlsruhe was far less rigorous than Weizmann’s in
the Pale.
But external circumstance is no sure measure of internal
wounding, and there are not many horrors as efficient for the generation of
deep anger and terrible lifelong insecurity as the inability of a father to
protect his child.
* * *
“In the last few years,” Niels Bohr wrote the German theoretical physicist
Arnold Sommerfeld at Munich in April 1922, “I have oen felt myself
scientifically very lonesome, under the impression that my effort to develop
the principles of the quantum theory systematically to the best of my ability
has been received with very little understanding.” 429 rough the war years
Bohr had struggled to follow, wherever it might lead, the “radical change” he
had introduced into physics.
It led to frustration.
However stunning Bohr’s
prewar results had been, too many older European scientists still thought his
inconsistent hypotheses ad hoc and the idea of a quantized atom repugnant.
e war itself stalled advance.
Yet he persisted, groping his way forward in the darkness.
“Only a rare
and uncanny intuition,” writes the Italian physicist Emilio Segrè, “saved
Bohr from getting lost in the maze.” 430 He guided himself delicately by what
he called the correspondence principle.
As Robert Oppenheimer once
explained it, “Bohr remembered that physics was physics and that Newton
described a great part of it and Maxwell a great part of it.” So Bohr assumed
that his quantum rules must approximate, “in situations where the actions
involved were large compared to the quantum, to the classical rules of
Newton and of Maxwell.
”431 at correspondence between the reliable old
and the unfamiliar new gave him an outer limit, a wall to feel his way along.
Bohr built his Institute for eoretical Physics with support from the
University of Copenhagen and from Danish private industry, occupying it
on January 18, 1921, aer more than a year of delay—he struggled with the
architect’s plans as painfully as he struggled with his scientific papers.
e
city of Copenhagen ceded land for the institute on the edge of the
Faelledpark, broad with soccer fields, where a carnival annually marks the
Danish celebration of Constitution Day.
e building itself was modest gray
stucco with a red tile roof, no larger than many private homes, with four
floors inside that looked like only three outside because the lowest floor was
built partly below grade and the top floor, which served the Bohrs at first as
an apartment, extended into the space under the peaked roof (later, as Bohr’s
family increased to five sons, he built a house next door and the apartment
served as living quarters for visiting students and colleagues).
e institute
included a lecture hall, a library, laboratories, offices and a popular PingPong
table where Bohr oen played.
“His reactions were very fast and accurate,”
says Otto Frisch, “and he had tremendous will power and stamina.
In a way
those qualities characterized his scientific work as well.” 432
In 1922, the year his Nobel Prize made him a Danish national hero, Bohr
accomplished a second great theoretical triumph: an explanation of the
atomic structure that underlies the regularities of the periodic table of the
elements.
It linked chemistry irrevocably to physics and is now standard in
every basic chemistry text.
Around the nucleus, Bohr proposed, atoms are
built up of successive orbital shells of electrons—imagine a set of nested
spheres—each shell capable of accommodating up to a certain number of
electrons and no more.
Elements that are similar chemically are similar
because they have identical numbers of electrons in their outermost shells,
available there for chemical combination.
Barium, for example, an alkaline
earth, the fiy-sixth element in the periodic table, atomic weight 137.34 , has
electron shells filled successively by 2, 8, 18, 18, 8 and 2 electrons.
Radium,
another alkaline earth, the eighty-eighth element, atomic weight 226, has
electron shells filled successively by 2, 8, 18, 32, 18, 8 and 2 electrons.
Because the outer shell of each element has two valence electrons, barium
and radium are chemically similar despite their considerable difference in
atomic weight and number.
“at [the] insecure and contradictory
foundation [of Bohr’s quantum hypotheses],” Einstein would say, “was
sufficient to enable a man of Bohr’s unique instinct and perceptiveness to
discover the major laws of spectral lines and of the electron shells of the
atom as well as their significance for chemistry appeared to me like a
miracle....
is is the highest form of musicality in the sphere of
thought.” 433
Confirming the miracle, Bohr predicted in the autumn of 1922 that
element 72 when discovered would not be a rare earth, as chemists expected
and as elements 57 through 71 are, but would rather be a valence 4 metal
like zirconium.
George de Hevesy, now settled in at Bohr’s institute, and a
newly arrived young Dutchman, Dirk Coster, went to work using X-ray
spectroscopy to look for the element in zircon-bearing minerals.
ey had
not finished their checking when Bohr went off with Margrethe in early
December to claim his Nobel Prize.
ey called him in Stockholm the night
before his Nobel lecture, only just in time: they had definitely identified
element 72 and it was chemically almost identical to zirconium.
ey named
the new element hafnium aer Hafnia, the old Roman name for
Copenhagen.
Bohr announced its discovery with pride at the conclusion of
his lecture the next day.
Despite his success with it, quantum theory needed a more solid
foundation than Bohr’s intuition.
Arnold Sommerfeld in Munich was an
early contributor to that work; aer the war the brightest young men,
searching out the growing point of physics, signed on to help.
Bohr
remembered the period as “a unique cooperation of a whole generation of
theoretical physicists from many countries,” an “unforgettable
experience.” 434 He was lonesome no more.
Sommerfeld brought with him to Göttingen in the early summer of 1922
his most promising student, a twenty-year-old Bavarian named Werner
Heisenberg, to hear Bohr as visiting lecturer there.
“I shall never forget the
first lecture,” Heisenberg wrote fiy years later, the memory still textured
with fine detail.
“e hall was filled to capacity.
e great Danish
physicist...
stood on the platform, his head slightly inclined, and a friendly
but somewhat embarrassed smile on his lips.
435 Summer light flooded in
through the wide-open windows.
Bohr spoke fairly soly, with a slight
Danish accent....
Each one of his carefully formulated sentences revealed a
long chain of underlying thoughts, of philosophical reflections, hinted at but
never fully expressed.
I found this approach highly exciting.”
Heisenberg nevertheless raised pointed objection to one of Bohr’s
statements.
Bohr had learned to be alert for bright students who were not
afraid to argue.
“At the end of the discussion he came over to me and asked
me to join him that aernoon on a walk over the Hain Mountain,”
Heisenberg remembers.
“My real scientific career only began that
aernoon.” 436 It is the memory of a conversion.
Bohr proposed that
Heisenberg find his way to Copenhagen eventually so that they could work
together.
“Suddenly, the future looked full of hope.
”437 At dinner the next
evening Bohr was startled to be challenged by two young men in the
uniforms of the Göttingen police.
One of them clapped him on the shoulder:
“You are arrested on the charge of kidnapping small children!” ey were
students, genial frauds.
438 e small child they guarded was Heisenberg,
boyish with freckles and a stiff brush of red hair.
Heisenberg was athletic, vigorous, eager—“radiant,” a close friend says.
“He looked even greener in those days than he really was, for, being a
member of the Youth Movement...
he oen wore, even aer reaching man’s
estate, an open shirt and walking shorts.” 439 In the Youth Movement young
Germans on hiking tours built campfires, sang folk songs, talked of
knighthood and the Holy Grail and of service to the Fatherland.
Many were
idealists, but authoritarianism and anti-Semitism already bloomed
poisonously among them.
When Heisenberg finally got to Copenhagen at
Eastertime in 1924 Bohr took him off on a hike through north Zealand and
asked him about it all.
“‘But now and then our papers also tell us about more
ominous, anti-Semitic, trends in Germany, obviously fostered by
demagogues,’ ” Heisenberg remembers Bohr questioning.
“ ‘Have you come
across any of that yourself?’ ” at was the work of some of the old officers
embittered by the war, Heisenberg said, “but we don’t take these groups very
seriously.” 440
Now, as part of the “unique cooperation” Bohr would speak of, they went
freshly to work on quantum theory.
Heisenberg seems to have begun with a
distaste for visualizing unmeasurable events.
As an undergraduate, for
example, he had been shocked to read in Plato’s Timaeus that atoms had
geometric forms: “It saddened me to find a philosopher of Plato’s critical
acumen succumbing to such fancies.” 441 e orbits of Bohr’s electrons were
similarly fanciful, Heisenberg thought, and Max Born and Wolfgang Pauli,
his colleagues at Göttingen, concurred.
No one could see inside an atom.
What was known and measurable was the light that came out of the atomic
interior, the frequencies and amplitudes associated with spectral lines.
Heisenberg decided to reject models entirely and look for regularities among
the numbers alone.
He returned to Göttingen as a Privatdozent working under Born.
Toward
the end of May 1925 his hay fever flared; he asked Born for two weeks’ leave
of absence and made his way to Heligoland, a stormy sliver of island twenty-
eight miles off the German coast in the North Sea, where very little pollen
blew.
He walked; he swam long distances in the cold sea; “a few days were
enough to jettison all the mathematical ballast that invariably encumbers the
beginning of such attempts, and to arrive at a simple formulation of my
problem.” 442 A few days more and he glimpsed the system he needed.
It
required a strange algebra that he cobbled together as he went along where
numbers multiplied in one direction oen produced different products from
the same numbers multiplied in the opposite direction.
He worried that his
system might violate the basic physical law of the conservation of energy
and he worked until three o’clock in the morning checking his figures,
nervously making mistakes.
By then he saw that he had “mathematical
consistency and coherence.” And so oen with deep physical discovery, the
experience was elating but also psychologically disturbing:
At first, I was deeply alarmed.
I had the feeling that, through the surface
of atomic phenomena, I was looking at a strangely beautiful interior, and
felt almost giddy at the thought that I now had to probe this wealth of
mathematical structures nature had so generously spread out before me.
I
was far too excited to sleep, and so, as a new day dawned, I made for the
southern tip of the island, where I had been longing to climb a rock
jutting out into the sea.
I now did so without too much trouble, and
waited for the sun to rise.
Back in Göttingen Max Born recognized Heisenberg’s strange
mathematics as matrix algebra, a mathematical system for representing and
manipulating arrays of numbers on matrices—grids—that had been devised
in the 1850s and that Born’s teacher David Hilbert had extended in 1904.
In
three months of intensive work Born, Heisenberg and their colleague
Pascual Jordan then developed what Heisenberg calls “a coherent
mathematical framework, one that promised to embrace all the multifarious
aspects of atomic physics.” 443 Quantum mechanics, the new system was
called.
It fit the experimental evidence to a high degree of accuracy.
Pauli
managed with heroic effort to apply it to the hydrogen atom and derive in a
consistent way the same results—the Balmer formula, Rydberg’s constant—
that Bohr had derived from inconsistent assumptions in 1913.
Bohr was
delighted.
At Copenhagen, at Göttingen, at Munich, at Cambridge, the work
of development went on.
* * *
e bow of the Carpathians as they curve around northwestward begins to
define the northern border of Czechoslovakia.
Long before it can complete
that service the bow bends down toward the Austrian Alps, but a border
region of mountainous upli, the Sudetes, continues across Czechoslovakia.
Some sixty miles beyond Prague it turns southwest to form a low range
between Czechoslovakia and Germany that is called, in German, the
Erzgebirge: the Ore Mountains.
e Erzgebirge began to be mined for iron
in medieval days.
In 1516 a rich silver lode was discovered in Joachimsthal
(St.
Joachim’s dale), in the territory of the Count von Schlick, who
immediately appropriated the mine.
In 1519 coins were first struck from its
silver at his command.
Joachimsthaler, the name for the new coins,
shortened to thaler, became “dollar” in English before 1600.
ereby the U.S.
dollar descends from the silver of Joachimsthal.
e Joachimsthal mines, ancient and cavernous, shored with smoky
timbers, offered up other unusual ores, including a black, pitchy, heavy,
nodular mineral descriptively named pitchblende.
A German apothecary
and self-taught chemist, Martin Heinrich Klaproth, who became the first
professor of chemistry at the University of Berlin when it opened its doors in
1810, succeeded in 1789 in extracting a grayish metallic material from a
sample of Joachimsthal pitchblende.
He sought an appropriate name.
Eight
years previously Sir William Herschel, the German-born English
astronomer, had discovered a new planet and named it Uranus aer the
earliest supreme god of Greek mythology, son and husband of Gaea, father
of Titans and Cyclopes, whose son Chronus with Gaea’s help castrated him
and from whose wounded blood, falling then on Earth, the three vengeful
Furies sprang.
To honor Herschel’s discovery Klaproth named his new metal
uranium.
It was found to serve, in the form of sodium and ammonium
diuranates, as an excellent coloring agent of ceramic glazes, giving a good
yellow at 0.006 percent and with higher percentages successively orange,
brown, green and black.
Uranium mining for ceramics, once begun,
continued modestly at Joachimsthal into the modern era.
It was from
Joachimsthal pitchblende residues that Marie and Pierre Curie laboriously
separated the first samples of the new elements they named radium and
polonium.
e radioactivity of the Erzgebirge ores thus lent glamour to the
region’s several spas, including Carlsbad and Marienbad, which could now
announce that their waters were not only naturally heated but dispersed
tonic radioactivity as well.
In the summer of 1921 a wealthy seventeen-year-old American student, a
recent graduate of the Ethical Culture School of New York, made his way to
Joachimsthal on an amateur prospecting trip.
Young Robert Oppenheimer
had begun collecting minerals when his grandfather, who lived in Hanau,
Germany, had given him a modest starter collection on a visit there when
Robert was a small boy, before the Great War.
He dated his interest in
science from that time.
“is was certainly at first a collector’s interest,” he
told an interviewer late in life, “but it began to be also a bit of a scientist’s
interest, not in historical problems of how rocks and minerals came to be,
but really a fascination with crystals, their structure, birefringence, what you
saw in polarized light, and all the canonical business.” e grandfather was
“an unsuccessful businessman, born himself in a hovel, really, in an almost
medieval German village, with a taste for scholarship.
”444 Oppenheimer’s
father had le Hanau for America at seventeen, in 1898, worked his way to
ownership of a textile-importing company and prospered importing lining
fabrics for men’s suits at a time when ready-made suits were replacing hand
tailoring in the United States.
e Oppenheimers—Julius; his beautiful and
delicate wife Ella, artistically trained, from Baltimore; Robert, born April 22,
1904; and Frank, Robert’s sidekick brother, eight years younger—could
afford to summer in Europe and frequently did so.
Julius and Ella Oppenheimer were people of dignity and some caution,
nonpracticing Jews.
ey lived in a spacious apartment on Riverside Drive
near 88th Street overlooking the Hudson River and kept a summer house at
Bay Shore on Long Island.
ey dressed with tailored care, practiced
cultivation, sheltered themselves and their children from real and imagined
harm.
Ella Oppenheimer’s congenitally unformed right hand, hidden always
in a prosthetic glove, was not discussed, not even by the boys out of earshot
among their friends.
She was loving but formal: in her presence only her
husband presumed to raise his voice.
Julius Oppenheimer, according to one
of Robert’s friends a great talker and social arguer, according to another was
“desperately amiable, anxious to be agreeable,” but also essentially kind.445 ,
446 He belonged to Columbia University educator Felix Adler’s Society for
Ethical Culture, of which Robert’s school was an extension, which declared
that “man must assume responsibility for the direction of his life and
destiny”: man, as opposed to God.
Robert Oppenheimer remembered
himself as “an unctuous, repulsively good little boy.” His childhood, he said,
“did not prepare me for the fact that the world is full of cruel and bitter
things.
It gave me no normal, healthy way to be a bastard.
”447 He was a frail
child, frequently ill.
For that reason, or because she had lost a middle son
shortly aer birth, his mother did not encourage him to run in the streets.
He stayed home, collected minerals and at ten years of age wrote poems but
still played with blocks.
He was already working up to science.
A professional microscope was a
childhood toy.
He did laboratory experiments in the third grade, began
keeping scientific notebooks in the fourth, began studying physics in the
fih, though for many years chemistry would interest him more.
e curator
of crystals at the American Museum of Natural History took him as a pupil.
He lectured to the surprised and then delighted members of the New York
Mineralogical Club when he was twelve—from the quality of his
correspondence the membership had assumed he was an adult.
When he was fourteen, to get him out of doors and perhaps to help him
find friends, his parents sent him to camp.
He walked the trails of Camp
Koenig looking for rocks and discoursing with the only friend he found on
George Eliot, emboldened by Eliot’s conviction that cause and effect ruled
human affairs.
He was shy, awkward, unbearably precious and
condescending and he did not fight back.
He wrote his parents that he was
glad to be at camp because he was learning the facts of life.
e
Oppenheimers came running.
When the camp director cracked down on
dirty jokes, the other boys, the ones who called Robert “Cutie,” traced the
censorship to him and hauled him off to the camp icehouse, stripped him
bare, beat him up—“tortured him,” his friend says—painted his genitals and
buttocks green and locked him away naked for the night.
448 Responsibly he
held out to the end of camp but never went back.
“Still a little boy,” another
childhood friend, a girl he liked more than she knew, remembers him at
fieen; “...
very frail, very pink-cheeked, very shy, and very brilliant of
course.
Very quickly everybody admitted that he was different from all the
others and very superior.
As far as studies were concerned he was good in
everything....
Aside from that he was physically—you can’t say clumsy
exactly—he was rather undeveloped, not in the way he behaved but the way
he went about, the way he walked, the way he sat.
ere was something
strangely childish about him.
”449
He graduated as Ethical Culture’s valedictorian in February 1921.
In April
he underwent surgery for appendicitis.
Recovered from that, he traveled
with his family to Europe and off on his side trip to Joachimsthal.
Somewhere along the way he “came down with a heavy, almost fatal case of
trench dysentery.” He was supposed to enter Harvard in September, but “I
was sick abed—in Europe, actually, at the time.
”450 Severe colitis following
the bout of dysentery laid him low for months.
He spent the winter in the
family apartment in New York.
To round off Robert’s convalescence and toughen him up, his father
arranged for a favorite English teacher at Ethical Culture, a warm,
supportive Harvard graduate named Herbert Smith, to take him out West
for the summer.
Robert was then eighteen, his face still boyish but steadied
by arresting blue-gray eyes.
He was six feet tall, on an extremely narrow
frame; he never in his life weighed more than 125 pounds and at times of
illness or stress could waste to 115.
Smith guided his charge to a dude ranch,
Los Piños, in the Sangre de Cristo Mountains northeast of Santa Fe, and
Robert chowed down, chopped wood, learned to ride horses and live in rain
and weather.
A highlight of the summer was a pack trip.
It started in Frijoles, a village
within sheer, pueblo-carved Cañon de los Frijoles across the Rio Grande
from the Sangre de Cristos, and ascended the canyons and mesas of the
Pajarito Plateau up to the Valle Grande of the vast Jemez Caldera above
10,000 feet.
e Jemez Caldera is a bowl-shaped volcanic crater twelve miles
across with a grassy basin inside 3,500 feet below the rim, the basin divided
by mountainous extrusions of lava into several high valleys.
It is a million
years old and one of the largest calderas in the world, visible even from the
moon.
Northward four miles from the Cañon de los Frijoles a parallel
canyon took its Spanish name from the cottonwoods that shaded its washes:
Los Alamos.
Young Robert Oppenheimer first approached it in the summer
of 1922.
Like Eastern semi-invalids in frontier days, Oppenheimer’s encounter
with wilderness, freeing him from overcivilized restraints, was decisive, a
healing of faith.
From an ill and perhaps hypochondriac boy he weathered
across a vigorous summer to a physically confident young man.
He arrived
at Harvard tanned and fit, his body at least in shape.
At Harvard he imagined himself a Goth coming into Rome.451 “He
intellectually looted the place,” a classmate says.
452 He routinely took six
courses for credit—the requirement was five—and audited four more.
Nor
were they easy courses.
He was majoring in chemistry, but a typical year
might include four semesters of chemistry, two of French literature, two of
mathematics, one of philosophy and three of physics, these only the courses
credited.
453 He read on his own as well, studied languages, found occasional
weekends for sailing the 27-foot sloop his father had given him or for
allnight hikes with friends, wrote short stories and poetry when the spirit
moved him but generally shied from extracurricular activities and groups.
Nor did he date; he was still unformed enough to brave no more than
worshiping older women from afar.
He judged later that “although I liked to
work, I spread myself very thin and got by with murder.” 454 e murder he
got by with resulted in a transcript solid with A’s sprinkled with B’s; he
graduated summa cum laude in three years.
ere is something frantic in all this grinding, however disguised in
traditional Harvard languor.
Oppenheimer had not yet found himself—is
that more difficult for Americans than for Europeans like Szilard or Teller,
who seem all of a piece from their earliest days?—and would not manage to
do so at Harvard.
Harvard, he would say, was “the most exciting time I’ve
ever had in my life.
I really had a chance to learn.
I loved it.
I almost came
alive.” 455 Behind the intellectual excitement there was pain.
He was always an intensely, even a cleverly, private man, but late in life he
revealed himself to a group of sensitive friends, a revelation that certainly
reaches back all the way to his undergraduate years.
“Up to now,” he told
that group in 1963, “and even more in the days of my almost infinitely
prolonged adolescence, I hardly took an action, hardly did anything or failed
to do anything, whether it was a paper in physics, or a lecture, or how I read
a book, how I talked to a friend, how I loved, that did not arouse in me a
very great sense of revulsion and of wrong.” 456 His friends at Harvard saw
little of this side—an American university is aer all a safe-house—but he
hinted of it in his letters to Herbert Smith:
Generously, you ask what I do.
Aside from the activities exposed in last
week’s disgusting note, I labor, and write innumerable theses, notes,
poems, stories, and junk; I go to the math lib[rary] and read and to the
Phil lib and divide my time between Meinherr [Bertrand] Russell and the
contemplation of a most beautiful and lovely lady who is writing a thesis
on Spinoza—charmingly ironic, at that, don’t you think?
I make stenches
in three different labs, listen to Allard gossip about Racine, serve tea and
talk learnedly to a few lost souls, go off for the weekend to distill the low
grade energy into laughter and exhaustion, read Greek, commit faux pas,
search my desk for letters, and wish I were dead.
Voila.
457
Part of that exaggerated death wish is Oppenheimer making himself
interesting to his counselor, but part of it is pure misery—considering its
probable weight, rather splendidly and courageously worn.
Both of Oppenheimer’s closest college friends, Francis Fergusson and Paul
Horgan, agree that he was prone to baroque exaggeration, to making more
of things than things could sustain on their own.
458 Since that tendency
would eventually ruin his life, it deserves to be examined.
Oppenheimer was
no longer a frightened boy, but he was still an insecure and uncertain young
man.
He sorted among information, knowledge, eras, systems, languages,
arcane and apposite skills in the spirit of trying them on for size.
Exaggeration made it clear that he knew you knew how awkwardly they fit
(and self-destructively at the same time supplied the awkwardness).
at
was perhaps its social function.
Deeper was worse.
Deeper was self-loathing,
“a very great sense of revulsion and of wrong.” Nothing was yet his, nothing
was original, and what he had appropriated through learning he thought
stolen and himself a thief: a Goth looting Rome.
He loved the loot but
despised the looter.
He was as clear as Harry Moseley was clear in his last
will about the difference between collectors and creators.
At the same time,
intellectual controls were the only controls he seems to have found at that
point in his life, and he could hardly abandon them.
He tried writing, poems and short stories.
His college letters are those of a
literary man more than of a scientist.
He would keep his literary skills and
they would serve him well, but he acquired them first of all for the access he
thought they might open to self-knowledge.
At the same time, he hoped
writing would somehow humanize him.
He read e Waste Land, newly
published, identified with its Weltschmerz and began to seek the stern
consolations of Hindu philosophy.
He worked through the rigors of
Bertrand Russell’s and Alfred North Whitehead’s three-volume Principia
Mathematica with Whitehead himself, newly arrived—only one other
student braved the seminar—and prided himself throughout his life on that
achievement.
Crucially, he began to find the physics that underlay the
chemistry, as he had found crystals emerging in clarity from the historical
complexity of rocks: “It came over me that what I liked in chemistry was
very close to physics; it’s obvious that if you were reading physical chemistry
and you began to run into thermodynamical and statistical mechanical ideas
you’d want to find out about them....
It’s a very odd picture; I never had an
elementary course in physics.” 459
He worked in the laboratory of Percy Bridgman, many years later a Nobel
laureate, “a man,” says Oppenheimer, “to whom one wanted to be an
apprentice.” 460 He learned much of physics, but haphazardly.
He graduated a
chemist and was foolhardy enough to imagine that Ernest Rutherford would
welcome him at Cambridge, where the Manchester physicist had moved in
1919 to take over direction of the Cavendish from the aging J.
J.
omson.
“But Rutherford wouldn’t have me,” Oppenheimer told a historian later.
“He
didn’t think much of Bridgman and my credentials were peculiar and not
impressive, and certainly not impressive to a man with Rutherford’s
common sense....
I don’t even know why I le Harvard, but I somehow felt
that [Cambridge] was more near the center.
”461 Nor would Bridgman’s letter
of recommendation, though well meant, have helped with Rutherford.
Oppenheimer had a “perfectly prodigious power of assimilation,” the
Harvard physicist wrote, and “his problems have in many cases shown a
high degree of originality in treatment and much mathematical power.” But
“his weakness is on the experimental side.
His type of mind is analytical,
rather than physical, and he is not at home in the manipulations of the
laboratory.” Bridgman said honestly that he thought Oppenheimer “a bit of a
gamble.
”462 On the other hand, “if he does make good at all, I believe that he
will be a very unusual success.” Aer another healing summer in New
Mexico with Paul Horgan and old friends from the summer of 1921,
Oppenheimer went off to Cambridge to attack the center where he could.
J.
J.
omson still worked at the Cavendish.
He let Oppenheimer in.
“I am
having a pretty bad time,” Oppenheimer wrote to Francis Fergusson at
Oxford on November 1.
“e lab work is a terrible bore, and I am so bad at
it that it is impossible to feel that I am learning anything....
e lectures are
vile.” Yet he thought “the academic standard here would depeople Harvard
overnight.” 463 He worked in one corner of a large basement room at the
Cavendish (the Garage, it was called); omson worked in another.
He
labored painfully to make thin films of beryllium for an experiment he
seems never to have finished—James Chadwick, who had moved down from
Manchester and was now Rutherford’s assistant director of research, later
put them to use.
“e business of the laboratory was really quite a sham,”
Oppenheimer recalled, “but it got me into the laboratory where I heard talk
and found out a good deal of what people were interested in.
”464
Postwar work on quantum theory was just then getting under way.
It
excited Oppenheimer enormously.
He wanted to be a part of it.
He was
afraid he might be too late.
All his learning had come easily before.
At
Cambridge he hit the wall.
It was as much an emotional wall as an intellectual, probably more.
“e
melancholy of the little boy who will not play because he has been snubbed,”
he described it three years later, aer he broke through.465 e British gave
him the same silent treatment they had given Niels Bohr, but he lacked
Bohr’s hard-earned self-confidence.
Herbert Smith sensed the approaching
disaster.
“How is Robert doing?” he wrote Fergusson.
“Is frigid England
hellish socially and climatically, as you found it?
Or does he enjoy its
exoticism?
I’ve a notion, by the way, that your ability to show him about
should be exercised with great tact, rather than in royal profusion.
Your
[two] years’ start and social adaptivity are likely to make him despair.
And
instead of flying at your throat...
I’m afraid he’d merely cease to think his
own life worth living.” 466 Oppenheimer wrote Smith in December that he
had not been busy “making a career for myself....
Really I have been
engaged in the far more difficult business of making myself for a career.
”467
It was worse than that.
He was in fact, as he later said, “on the point of
bumping myself off.
is was chronic.” 468 He saw Fergusson at
Christmastime in Paris and reported despair at his lab work and frustration
with sexual ventures.
en, contradicting Smith’s prediction, he flew at
Fergusson’s throat and tried to strangle him.
Fergusson easily set him aside.
Back at Cambridge Oppenheimer tried a letter of explanation.
He wrote that
he was sending Fergusson a “noisy” poem.
“I have le out, and that is
probably where the fun came in, just as I did in Paris, the awful fact of
excellence; but as you know, it is that fact now, combined with my inability
to solder two copper wires together, which is probably succeeding in getting
me crazy.” 469
e awful fact of excellence did not continue to elude him.
As he
approached a point of psychological crisis he also drove hard to extend
himself, understanding deeply that his mind must pull him through.
He was
“doing a tremendous amount of work,” a friend said, “thinking, reading,
discussing things, but obviously with a sense of great inner anxiety and
alarm.” 470 A crucial change that year was his first meeting with Bohr.
“When Rutherford introduced me to Bohr he asked me what I was working on.
I
told him and he said, ‘How is it going?’ I said, ‘I’m in difficulties.’ He said,
‘Are the difficulties mathematical or physical?’ I said, ‘I don’t know.’ He said,
‘at’s bad.’ ” 471 But something about Bohr—his avuncular warmth at least,
what C.
P.
Snow calls his simple and genuine kindness, his uninsipid
“sweetness”—helped release Oppenheimer to commitment: “At that point I
forgot about beryllium and films and decided to try to learn the trade of
being a theoretical physicist.” 472, 473
Whether the decision precipitated the crisis or began to relieve it is not
clear from the record.
Oppenheimer visited a Cambridge psychiatrist.
Someone wrote his parents about his problems and they hurried over as they
had hurried to Camp Koenig years before.
ey pushed their son to see a
new psychiatrist.
He found one in London on Harley Street.
Aer a few
sessions the man diagnosed dementia praecox, the older term for what is
now called schizophrenia, a condition characterized by early adult onset,
faulty thought processes, bizarre actions, a tendency to live in an inner
world, incapacity to maintain normal interpersonal relationships and an
extremely poor prognosis.
Given the vagueness of the symptomatology and
Oppenheimer’s intellectual dazzle and profound distress, the psychiatrist’s
mistake is easy enough to understand.
Fergusson met Oppenheimer in
Harley Street one day and asked him how it had gone.
“He said...
that the
guy was too stupid to follow him and that he knew more about his troubles
than the [doctor] did, which was probably true.
”474
Resolution began before the consultations on Harley Street, in the spring,
on a ten-day visit to Corsica with two American friends.
What happened to
bring Oppenheimer through is a mystery, but a mystery important enough
to him that he deliberately emphasized it—tantalizingly and incompletely—
to one of the more sensitive of his profilers, Nuel Pharr Davis.
Corsica,
Oppenheimer wrote his brother Frank soon aer his visit, was “a great place,
with every virtue from wine to glaciers, and from langouste to
brigantines.
”475 To Davis, late in life, he emphasized that although the
United States Government had assembled hundreds of pages of information
about him across the years, so that some people said his entire life was
recorded there, the record in fact contained almost nothing of real
importance.
To prove his point, he said, he would mention Corsica.
“e
[Cambridge] psychiatrist was a prelude to what began for me in Corsica.
You ask whether I will tell you the full story or whether you must dig it out.
But it is known to few and they won’t tell.
You can’t dig it out.
What you
need to know is that it was not a mere love affair, not a love affair at all, but
love.” 476 It was, he said, “a great thing in my life, a great and lasting part of
it.” 477
Whether a love affair or love, Oppenheimer found his vocation in
Cambridge that year: that was the certain healing.
Science saved him from
emotional disaster as science was saving Teller from social disaster.
He
moved to Göttingen, the old medieval town in Lower Saxony in central
Germany with the university established by George II of England, in the
autumn of 1926, late Weimar years.
Max Born headed the university physics
department, newly installed in institute buildings on Bunsenstrasse funded
by the Rockefeller Foundation.
Eugene Wigner traveled to Göttingen to
work with Born, as had Werner Heisenberg and Wolfgang Pauli and, less
happily, the Italian Enrico Fermi, all future Nobel laureates.
James Franck,
having moved over from Haber’s institute at the KWI, a Nobelist as of 1925,
supervised laboratory classes.
e mathematicians Richard Courant,
Herman Weyl and John von Neumann collaborated.
Edward Teller would
show up later on an assistantship.
e town was pleasant, for visiting Americans at least.
ey could drink
frisches Bier at the fieenth-century Schwartzen Bären, the Black Bears, and
sit to crisp, delicate wiener Schnitzel at the Junkernschänke, the Junkers’
Hall, under a steel engraving of former patron Otto von Bismarck.
e
Junkernschänke, four hundred years old, occupied three stories of stained
glass and flowered half-timber at the corner of Barefoot and Jew streets,
which makes it likely that Oppenheimer dined there: he would have
appreciated the juxtaposition.
When a student took his doctorate at
Göttingen he was required by his classmates to kiss the Goose Girl, a pretty,
lifesize bronze maiden within a bronze floral arbor that decorates the
fountain on the square in front of the medieval town hall.
To reach the lips
of the Gänseliesel required wading or leaping the fountain pool, the real
point of the exercise, a baptism into professional distinction Oppenheimer
must have welcomed.
e townspeople still suffered from the disaster of the war and the
inflation.
Oppenheimer and other American students lodged at the walled
mansion of a Göttingen physician who had lost everything and was forced
to take in boarders.
“Although this society [at the university] was extremely
rich and warm and helpful to me,” Oppenheimer says, “it was parked there
in a very miserable German mood...
bitter, sullen, and, I would say,
discontent and angry and with all those ingredients which were later to
produce a major disaster.
And this I felt very much.” 478 At Göttingen he first
measured the depth of German ruin.
Teller generalized it later from his own
experience of lost wars and their aermaths: “Not only do wars create
incredible suffering, but they engender deep hatreds that can last for
generations.” 479
Two of Oppenheimer’s papers, “On the quantum theory of
vibrationrotation bands” and “On the quantum theory of the problem of the
two bodies,” had already been accepted for publication in the Proceedings of
the Cambridge Philosophical Society when he arrived at Göttingen, which
helped to pave the way.
As he came to his vocation the papers multiplied.
His work was no longer apprenticeship but solid achievement.
His special
contribution, appropriate to the sweep of his mind, was to extend quantum
theory beyond its narrow initial ground.
His dissertation, “On the quantum
theory of continuous spectra,” was published in German in the prestigious
Zeitschri für Physik.
Born marked it “with distinction”—high praise indeed.
Oppenheimer and Born jointly worked out the quantum theory of
molecules, an important and enduring contribution.
Counting the
dissertation, Oppenheimer published sixteen papers between 1926 and
1929.
ey established for him an international reputation as a theoretical
physicist.
He came home a far more confident man.
Harvard offered him a job; so
did the young, vigorous California Institute of Technology at Pasadena.
e
University of California at Berkeley especially interested him because it was,
as he said later, “a desert,” meaning it taught no theoretical physics yet at
all.
480 He decided to take Berkeley and Caltech both, arranging to lecture on
the Bay Area campus in the autumn and winter and shi to Pasadena in the
spring.
But first he went back to Europe on a National Research Council
fellowship to tighten up his mathematics with Paul Ehrenfest at Leiden and
then with Pauli, now at Zurich, a mind more analytical and critical even
than Oppenheimer’s, a taste in physics more refined.
Aer Ehrenfest
Oppenheimer had wanted to work in Copenhagen with Bohr.
Ehrenfest
thought not: Bohr’s “largeness and vagueness,” in Oppenheimer’s words,
were not the proper astringent.
“I did see a copy of the letter [Ehrenfest]
wrote Pauli.
It was clear that he was sending me there to be fixed up.
”481
Before he le the United States for Leiden Oppenheimer visited the
Sangre de Cristos with Frank.
e two brothers found a cabin and a piece of
land they liked—“house and six acres and stream,” in Robert’s terse
description—up high on a mountain meadow.
482 e house was rough-
hewn timber chinked with caulk; it lacked even a privy.
While Robert was in
Europe his father arranged a long-term lease and set aside three hundred
dollars for what Oppenheimer calls “restoration.” A summer in the
mountains was restoration for the celebrated young theoretician as well.
* * *
At the end of that summer of 1927 the Fascist government of Benito
Mussolini convened an International Physical Congress at Como on the
southwestern end of ord-like Lake Como in the lake district of northern
Italy.
e congress commemorated the centennial of the death in 1827 of
Alessandro Volta, the Como-born Italian physicist who invented the electric
battery and aer whom the standard unit of electrical potential, the volt, is
named.
Everyone went to Como except Einstein, who refused to lend his
prestige to Fascism.
483 Everyone went because quantum theory was
beleaguered and Niels Bohr was scheduled to speak in its defense.
At issue was an old problem that had emerged in a new and more
challenging form.
Einstein’s 1905 work on the photoelectric effect had
demonstrated that light sometimes behaves as if it consists not of waves but
of particles.
Turning the tables, early in 1926 an articulate, cultured
Viennese theoretical physicist named Erwin Schrödinger published a wave
theory of matter demonstrating that matter at the atomic level behaves as if
it consists of waves.
Schrödinger’s theory was elegant, accessible and
completely consistent.
Its equations produced the quantized energy levels of
the Bohr atom, but as harmonics of vibrating matter “waves” rather than as
jumping electrons.
Schrödinger soon thereaer proved that his “wave
mechanics” was mathematically equivalent to quantum mechanics.
“In other
words,” says Heisenberg, “...
the two were but different mathematical
formulations of the same structure.
”484 at pleased the quantum
mechanicists because it strengthened their case and because Schrödinger’s
more straightforward mathematics simplified calculation.
But Schrödinger, whose sympathies lay with the older classical physics,
made more far-reaching claims for his wave mechanics.
In effect, he claimed
that it represented the reality of the interior of the atom, that not particles
but standing matter waves resided there, that the atom was thereby
recovered for the classical physics of continuous process and absolute
determinism.
In Bohr’s atom electrons navigated stationary states in
quantum jumps that resulted in the emission of photons of light.
Schrödinger offered, instead, multiple waves of matter that produced light by
the process known as constructive interference, the waves adding their
peaks of amplitude together.
“is hypothesis,” says Heisenberg dryly,
“seemed to be too good to be true.” 485 For one thing, Planck’s quantized
radiation formula of 1900, by now exhaustively proven experimentally,
opposed it.
But many traditional physicists, who had never liked quantum
theory, greeted Schrödinger’s work, in Heisenberg’s words, “with a sense of
liberation.” 486 Late in the summer, hoping to talk over the problem,
Heisenberg turned up at a seminar in Munich where Schrödinger was
speaking.
He raised his objections.
“Wilhelm Wien, [a Nobel laureate] who
held the chair of experimental physics at the University of Munich, answered
rather sharply that one must really put an end to quantum jumps and the
whole atomic mysticism, and the difficulties I had mentioned would
certainly soon be solved by Schrödinger.” 487
Bohr invited Schrödinger to Copenhagen.
e debate began at the
railroad station and continued morning and night, says Heisenberg:
For though Bohr was an unusually considerate and obliging person, he
was able in such a discussion, which concerned epistemological problems
which he considered to be of vital importance, to insist fanatically and
with almost terrifying relentlessness on complete clarity in all arguments.
He would not give up, even aer hours of struggling, [until] Schrödinger
had admitted that [his] interpretation was insufficient, and could not even
explain Planck’s law.
Every attempt from Schrödinger’s side to get round
this bitter result was slowly refuted point by point in infinitely laborious
discussions.488
Schrödinger came down with a cold and took to his bed.
Unfortunately he
was staying at the Bohrs’.
“While Mrs.
Bohr nursed him and brought in tea
and cake, Niels Bohr kept sitting on the edge of the bed talking at [him]: ‘But
you must surely admit that...’ ” 489 Schrödinger approached desperation.
“If
one has to go on with these damned quantum jumps,” he exploded, “then
I’m sorry that I ever started to work on atomic theory.” Bohr, always glad for
conflicts that sharpened understanding, calmed his exhausted guest with
praise: “But the rest of us are so grateful that you did, for you have thus
brought atomic physics a decisive step forward.” 490 Schrödinger returned
home discouraged but unconvinced.
Bohr and Heisenberg then went to work on the problem of reconciling the
dualisms of atomic theory.
Bohr hoped to formulate an approach that would
allow matter and light to exist both as particle and as wave; Heisenberg
argued consistently for abandoning models entirely and sticking to
mathematics.
In late February 1927, says Heisenberg, both of them “utterly
exhausted and rather tense,” Bohr went off to Norway to ski.
491 e young
Bavarian tried, using quantum-mechanical equations, to calculate
something so seemingly simple as the trajectory of an electron in a cloud
chamber and realized it was hopeless.
Facing that corner, he turned around.
“I began to wonder whether we might not have been asking the wrong sort
of question all along.”
Working late one evening in his room under the eaves of Bohr’s institute
Heisenberg remembered a paradox Einstein had thrown at him in a
conversation about the value of theory in scientific work.
“It is the theory
which decides what we can observe,” Einstein had said.
492 e memory
made Heisenberg restless; he went downstairs and let himself out—it was
aer midnight—and walked past the great beech trees behind the institute
into the open soccer fields of the Faelledpark.
It was early March and it
would have been cold, but Heisenberg was a vigorous walker who did his
best thinking outdoors.
“On this walk under the stars, the obvious idea
occurred to me that one should postulate that nature allowed only
experimental situations to occur which could be described within the
framework of the [mathematical] formalism of quantum mechanics.
”493 e
bald statement sounds wondrously arbitrary; its test would be its consistent
mathematical formulation and, ultimately, its predictive power for
experiment.
But it led Heisenberg immediately to a stunning conclusion:
that on the extremely small scale of the atom, there must be inherent limits
to how precisely events could be known.
If you identified the position of a
particle—by allowing it to impact on a zinc-sulfide screen, for example, as
Rutherford did—you changed its velocity and so lost that information.
If
you measured its velocity—by scattering gamma rays from it, perhaps—your
energetic gamma-ray photons battered it into a different path and you could
not then locate precisely where it was.
One measurement always made the
other measurement uncertain.
Heisenberg climbed back to his room and began formulating his idea
mathematically: the product of the uncertainties in the measured values of
the position and momentum cannot be smaller than Planck’s constant.
So h
appeared again at the heart of physics to define the basic, unresolvable
granularity of the universe.
What Heisenberg conceived that night came to
be called the uncertainty principle, and it meant the end of strict
determinism in physics: because if atomic events are inherently blurred, if it
is impossible to assemble complete information about the location of
individual particles in time and space, then predictions of their future
behavior can only be statistical.
e dream or bad joke of the Marquis de
Laplace, the eighteenth-century French mathematician and astronomer, that
if he knew at one moment the precise location in time and space of every
particle in the universe he could predict the future forever, was thus
answered late at night in a Copenhagen park: nature blurs that divine
prerogative away.
Bohr ought to have liked Heisenberg’s democratization of the atomic
interior.
494 Instead it bothered him: he had returned from his ski trip with a
grander conception of his own, one that reached back for its force to his
earliest understanding of doubleness and ambiguity, to Poul Martin Møller
and Søren Kierkegaard.
He was particularly unhappy that his Bavarian
protégé had not founded his uncertainty principle on the dualism between
particles and waves.
He trained on him the “terrifying relentlessness” he had
previously directed at Schrödinger.
Oskar Klein, Bohr’s amanuensis of the
period, fortunately mediated.
But Heisenberg was only twenty-six, however
brilliant.
He gave ground.
e uncertainty principle, he agreed, was just a
special case of the more general conception Bohr had devised.
With that
concession Bohr allowed the paper Heisenberg had written to go to the
printer.
And set to work composing his Como address.
At Como in pleasant September Bohr began with a polite reference to
Volta, “the great genius whom we are here assembled to commemorate,”
then plunged in.
He proposed to try to develop “a certain general point of
view” which might help “to harmonize the apparently conflicting views
taken by different scientists.” 495 e problem, Bohr said, was that quantum
conditions ruled on the atomic scale but our instruments for measuring
those conditions—our senses, ultimately—worked in classical ways.
at
inadequacy imposed necessary limitations on what we could know.
An
experiment that demonstrates that light travels in photons is valid within the
limits of its terms.
An experiment that demonstrates that light travels in
waves is equally valid within its limits.
e same is true of particles and
waves of matter.
e reason both could be accepted as valid is that
“particles” and “waves” are words, are abstractions.
What we know is not
particles and waves but the equipment of our experiments and how that
equipment changes in experimental use.
e equipment is large, the
interiors of atoms small, and between the two must be interposed a
necessary and limiting translation.
e solution, Bohr went on, is to accept the different and mutually
exclusive results as equally valid and stand them side by side to build up a
composite picture of the atomic domain.
Nur die Fülle führt zur Klarheit:
only wholeness leads to clarity.
Bohr was never interested in an arrogant
reductionism.
He called instead—the word appears repeatedly in his Como
lecture—for “renunciation,” renunciation of the godlike determinism of
classical physics where the intimate scale of the atomic interior was
concerned.
496 e name he chose for this “general point of view” was
complementarity, a word that derives from the Latin complementum, “that
which fills up or completes.” Light as particle and light as wave, matter as
particle and matter as wave, were mutually exclusive abstractions that
complemented each other.
ey could not be merged or resolved; they had
to stand side by side in their seeming paradox and contradiction; but
accepting that uncomfortably non-Aristotelian condition meant physics
could know more than it otherwise knew.
And furthermore, as Heisenberg’s
recently published uncertainty principle demonstrated within its limited
context, the universe appeared to be arranged that way as far down as
human senses would ever be able to see.
Emilio Segrè, who heard Bohr lecture at Como in 1927 as a young
engineering student, explains complementarity simply and clearly in a
history of modern physics he wrote in retirement: “Two magnitudes are
complementary when the measurement of one of them prevents the
accurate simultaneous measurement of the other.497 Similarly, two concepts
are complementary when one imposes limitations on the other.”
Carefully Bohr then examined the conflicts of classical and quantum
physics one at a time and showed how complementarity clarified them.
In
conclusion he briefly pointed to complementarity’s connection to
philosophy.
e situation in physics, he said, “bears a deep-going analogy to
the general difficulty in the formation of human ideas, inherent in the
distinction between subject and object.” 498 at reached back all the way to
the licentiate’s dilemma in Adventures of a Danish Student, and resolved it:
the I who thinks and the I who acts are different, mutually exclusive, but
complementary abstractions of the self.
In the years to come Bohr would extend the compass of his “certain
general point of view” far into the world.
It would serve him as a guide not
only in questions of physics but in the largest questions of statesmanship as
well.
But it never commanded the central place in physics he hoped it
would.
At Como a substantial minority of the older physicists were
predictably unpersuaded.
Nor was Einstein converted when he heard.
In
1926 he had written to Max Born concerning the statistical nature of
quantum theory that “quantum mechanics demands serious attention.
But
an inner voice tells me that this is not the true Jacob.
e theory
accomplishes a lot, but it does not bring us closer to the secrets of the Old
One.
In any case, I am convinced that He does not play dice.
”499 Another
physics conference, the annual Solvay Conference sponsored by a wealthy
Belgian industrial chemist named Ernest Solvay, was held in Brussels a
month aer Como.
Einstein attended, as did Bohr, Max Planck, Marie Curie,
Hendrick Lorentz, Max Born, Paul Ehrenfest, Erwin Schrödinger, Wolfgang
Pauli, Werner Heisenberg and a crowd of others.
“We all stayed at the same
hotel,” Heisenberg remembers, “and the keenest arguments took place, not
in the conference hall but during the hotel meals.
Bohr and Einstein were in
the thick of it all.
”500
Einstein refused to accept the idea that determinism on the atomic level
was forbidden, that the fine structure of the universe was unknowable, that
statistics rule.
“ ‘God does not throw dice’ was a phrase we oen heard from
his lips in these discussions,” writes Heisenberg.
“And so he refused point-
blank to accept the uncertainty principle, and tried to think up cases in
which the principle would not hold.” Einstein would produce a challenging
thought experiment at breakfast, the debate would go on all day, “and, as a
rule, by suppertime we would have reached a point where Niels Bohr could
prove to Einstein that even his latest experiment failed to shake the
uncertainty principle.
Einstein would look a bit worried, but by next
morning he was ready with a new imaginary experiment more complicated
than the last.
”501 is went on for days, until Ehrenfest chided Einstein—
they were the oldest of friends—that he was ashamed of him, that Einstein
was arguing against quantum theory just as irrationally as his opponents had
argued against relativity theory.
Einstein remained adamant (he remained
adamant to the end of his life where quantum theory was concerned).
Bohr, for his part, supple pragmatist and democrat that he was, never an
absolutist, heard once too oen about Einstein’s personal insight into the
gambling habits of the Deity.
He scolded his distinguished colleague finally
in Einstein’s own terms.
God does not throw dice?
“Nor is it our business to
prescribe to God how He should run the world.
”502
6
Machines
Aer the war, under Ernest Rutherford’s direction, the Cavendish thrived.
Robert Oppenheimer suffered there largely because he was not an
experimentalist; for experimental physicists, Cambridge was exactly the
center that Oppenheimer had thought it to be.
C.
P.
Snow trained there a
little later, in the early 1930s, and in his first novel, e Search, published in
1934, celebrated the experience in the narrative of a fictional young scientist:
I shall not easily forget those Wednesday meetings in the Cavendish.
For
me they were the essence of all the personal excitement in science; they
were romantic, if you like, and not on the plane of the highest experience
I was soon to know [of scientific discovery]; but week aer week I went
away through the raw nights, with east winds howling from the fens down
the old streets, full of a glow that I had seen and heard and been close to
the leaders of the greatest movement in the world.503
More crowded than ever, the laboratory was showing signs of wear and
tear.
Mark Oliphant remembers standing in the hallway outside Rutherford’s
office for the first time and noticing “uncarpeted floor boards, dingy
varnished pine doors and stained plastered walls, indifferently lit by a
skylight with dirty glass.
”504 Oliphant also records Rutherford’s appearance
at that time, the late 1920s, when the Cavendish director was in his
midfiies: “I was received genially by a large, rather florid man, with
thinning fair hair and a large moustache, who reminded me forcibly of the
keeper of the general store and post office in a little village in the hills
behind Adelaide where I had spent part of my childhood.
Rutherford made
me feel welcome and at ease at once.
He spluttered a little as he talked, from
time to time holding a match to a pipe which produced smoke and ash like a
volcano.”
With simple experimental apparatus Rutherford continued to produce
astonishing discoveries.
e most important of them besides the discovery
of the nucleus had come to fruition in 1919, shortly before he le
Manchester for Cambridge—he sent off the paper in April.
Aerward, at the
Cavendish, he and James Chadwick followed through.
e 1919 Manchester
paper actually summarized a series of investigations Rutherford carried out
in his rare moments of spare time during the four years of war, when he kept
the Manchester lab going almost singlehandedly while doing research for
the Admiralty on submarine detection.
It appeared in four parts.
e first
three parts cleared the way for the fourth, “An anomalous effect in nitrogen,”
which was revolutionary.
505
Ernest Marsden, whose examination of alpha scattering had led
Rutherford to discover the atomic nucleus, had found a similarly fruitful
oddity in the course of routine experimental studies at Manchester in 1915.
Marsden was using alpha particles—helium nuclei, atomic weight 4—
emanating from a small glass tube of radon gas to bombard hydrogen atoms.
He did that by fixing the radon tube inside a sealed brass box fitted at one
end with a zinc-sulfide scintillation screen, evacuating the box of air and
then filling it with hydrogen gas.
e alpha particles emanating from the
radon bounced off the hydrogen atoms (atomic weight approximately 1) like
marbles, transferring energy to the H atoms and setting some of them in
motion toward the scintillation screen; Marsden then measured their range
by interposing pieces of absorbing metal foils behind the screen until the
scintillations stopped.
Predictably, the less massive H atoms recoiled farther
as a result of their collisions with the heavier alpha particles than did the
alphas—about four times as far, says Rutherford—just as smaller and larger
marbles colliding in a marbles game do.
at was straightforward enough.
But then Marsden noticed, Rutherford
relates, while the box was evacuated, that the glass radon tube itself “gave
rise to a number of scintillations like those from hydrogen.” He tried a tube
made of quartz, then a nickel disk coated with a radium compound, and
found similarly bright, H-like scintillations.
“Marsden concluded that there
was strong evidence that hydrogen arose from the radioactive matter
itself.
”506 is conjecture would have been stunning, if true—so far
radioactive atoms had been found to eject only helium nuclei, beta electrons
and gamma rays in the course of their decay—but it was not the only
possible deduction.
Nor was it one that Rutherford, who aer all had
discovered two of the three basic radiations and had never found hydrogen
among them, was likely to accept out of hand.
Marsden had returned to New
Zealand in 1915 to teach; Rutherford pursued the strange anomaly.
He had a
good idea what he was aer.
“I occasionally find an odd half day to try a few
of my own experiments,” he wrote Bohr on December 9, 1917, “and have got
I think results that will ultimately prove of great importance.
I wish you were
here to talk matters over with.
I am detecting and counting the lighter atoms
set in motion by [alpha] particles....
I am also trying to break up the atom
by this method.” 507
His equipment was similar to Marsden’s, a small brass box fitted with
stopcocks to admit and evacuate gases from its interior, with a scintillation
screen mounted on one end.
For an alpha source he used a beveled brass
disk coated with a radium compound:
Arrangement of Ernest Rutherford’s experiment: D, alpha source.
S, zinc sulfide scintillation
screen.
M, microscope.
e likeliest explanation for Marsden’s anomalous H atoms was
contamination; hydrogen is light and chemically active and a minor
component of the ubiquitous air.
So Rutherford’s problem was basically one
of rigorous exclusion.
He needed to narrow down the possible sources of
hydrogen atoms in his box until he could conclusively prove their point of
origin.
He started by showing that they did not come from the radioactive
materials alone.
He established that they had the same mass and expected
range as the H atoms that recoiled from alpha bombardment of hydrogen
gas in Marsden’s experiment.
He admitted dry oxygen into the evacuated
brass box, then carbon dioxide, and found in both cases that the H atoms
coming off the radioactive source were slowed down by colliding with the
atoms of those gases—fewer scintillations showed up on the screen.
en he tried dry air.
e result surprised him.
Instead of decreasing the
number of scintillations, as oxygen and carbon dioxide had done, dry air
increased them— doubled them in fact.
ese newfound scintillations “appeared to the eye to be about equal in
brightness to H scintillations,” Rutherford notes cautiously near the
beginning of the revolutionary Part IV of his paper.
508 He went aer them.
If
they were H atoms, they still might be contaminants.
He eliminated that
possibility first.
He showed that they could not be due merely to the
hydrogen in water vapor (H2O): drying the air even more thoroughly made
little difference in their number.
Dust might harbor H atoms like dangerous
germs: he filtered the air he let into the box through long plugs of absorbent
cotton but found little change.
Since the increase in H atoms occurred in air but not in oxygen or carbon
dioxide, Rutherford deduced then that it “must be due either to nitrogen or
to one of the other gases present in atmospheric air.” And since air is 78
percent nitrogen, that gas appeared to be the likeliest candidate.
He tested it
simply, by comparing scintillations from air to scintillations from pure
nitrogen.
e test confirmed his hunch: “With pure nitrogen, the number of
long-range scintillations under similar conditions was greater than in air.
”509
Finally, Rutherford established that the H atoms came in fact from the
nitrogen and not from the radioactive source alone.
And then he made his
stunning announcement, couching it as always in the measured
understatement of British science: “From the results so far obtained it is
difficult to avoid the conclusion that the long-range atoms arising from
collision of [alpha] particles with nitrogen are not nitrogen atoms but
probably atoms of hydrogen....
If this be the case, we must conclude that
the nitrogen atom is disintegrated.
”510 Newspapers soon published the
discovery in plainer words: Sir Ernest Rutherford, headlines blared in 1919,
had split the atom.
It was less a split than a transmutation, the first artificial transmutation
ever achieved.
When an alpha particle, atomic weight 4, collided with a
nitrogen atom, atomic weight 14, knocking out a hydrogen nucleus (which
Rutherford would shortly propose calling a proton), the net result was a new
atom of oxygen in the form of the oxygen isotope 017: 4 plus 14 minus 1.
ere would hardly be enough 017 to breathe; only about one alpha particle
in 300,000 crashed through the electrical barrier around the nitrogen
nucleus to do its alchemical work.
511
But the discovery offered a new way to study the nucleus.
Physicists had
been confined so far to bouncing radiation off its exterior or measuring the
radiation that naturally came out of the nucleus during radioactive decay.
Now they had a technique for probing its insides as well.
Rutherford and
Chadwick soon went aer other light atoms to see if they also could be
disintegrated, and as it turned out, many of them—boron, fluorine, sodium,
aluminum, phosphorus—could.
But farther along the periodic table a
barricade loomed.
e naturally radioactive sources Rutherford used
emitted relatively slow-moving alpha particles that lacked the power to
penetrate past the increasingly formidable electrical barriers of heavier
nuclei.
Chadwick and others at the Cavendish began to talk of finding ways
to accelerate particles to higher velocities.
Rutherford, who scorned complex
equipment, resisted.
Particle acceleration was in any case difficult to do.
For
a time the newborn science of nuclear physics stalled.
* * *
Besides Rutherford’s crowd of “boys,” several individual researchers worked
at the Cavendish, legatees of J.
J.
omson.
One who pursued a different but
related interest was a slim, handsome, athletic, wealthy experimentalist
named Francis William Aston, the son of a Birmingham gunmaker’s
daughter and a Harborne metal merchant.
512 As a child Aston made picric-
acid bombs from soda-bottle cartridges and designed and launched huge
tissue-paper fire balloons; as an adult, a lifelong bachelor, heir aer 1908 to
his father’s wealth, he skied, built and raced motorcycles, played the cello
and took elegant trips around the world, stopping off in Honolulu in 1909, at
thirty-two, to learn surfing, which he thereaer declared to be the finest of
all sports.
Aston was one of Rutherford’s regular Sunday partners at golf on
the Gogs in Cambridge.
It was he who had announced, at the 1913 meeting
of the British Association, the separation of neon into two isotopes by
laborious diffusion through pipe clay.
Aston trained originally as a chemist; Röntgen’s discovery of X rays turned
him to physics.
J.
J.
omson brought him into the Cavendish in 1910, and it
was because omson seemed to have separated neon into two components
inside a positive-ray discharge tube that Aston took up the laborious work of
attempting to confirm the difference by gaseous diffusion.
omson found
that he could separate beams of different kinds of atoms by subjecting his
discharge tube to parallel magnetic and electrostatic fields.
e beams he
produced inside his tubes were not cathode rays; he was working now with
“rays” repelled from the opposite plate, the positively charged anode.
Such
rays were streams of atomic nuclei stripped of their electrons: ionized.
ey
could be generated from gas introduced into the tube.
Or solid materials
could be coated onto the anode plate itself, in which case ionized atoms of
the material would boil off when the tube was evacuated and the anode was
charged.
Mixed nuclei projected in a radiant beam through a magnetic field would
bend into separated component beams according to their velocity, which
gave a measure of their mass.
An electrostatic field bent the component
beams differently depending on their electrical charge, which gave a
measure of their atomic number.
“In this way,” writes George de Hevesy, “a
great variety of different atoms and atomic groupings were proved to be
present in the discharge tube.” 513
Aston thought hard about J.
J.’s discharge tube while he worked during the
war at the Royal Aircra Establishment at Farnborough, southwest of
London, developing tougher dopes and fabrics for aircra coverings.
He
wanted to prove unequivocally that neon was isotopic—J.
J.
was still
unconvinced—and saw the possibility of sorting the isotopes of other
elements as well.
He thought the positive-ray tube was the answer, but
though it was good for general surveying, it was hopelessly imprecise.
By the time Aston returned to Cambridge in 1918 he had worked the
problem out theoretically; he then began building the precision instrument
he had envisioned.
514 It charged a gas or a coating until the material ionized
into its component electrons and nuclei and projected the nuclei through
two slits that produced a knife-edge beam like the slit-narrowed beam of
light in a spectrograph.
It then subjected the beam to a strong electrostatic
field; that sorted the different nuclei into separated beams.
e separated
beams proceeded onward through a magnetic field; that further sorted
nuclei according to their mass, producing separated beams of isotopes.
Finally the sorted beams struck the plateholder of a camera and marked
their precise locations on a calibrated strip of film.
How much the magnetic
field bent the separated beams—where they blackened the strip of film—
determined the mass of their component nuclei to a high degree of accuracy.
Aston called his invention a mass-spectrograph because it sorted elements
and isotopes of elements by mass much as an optical spectrograph sorts light
by its frequency.
e mass-spectrograph was immediately and sensationally
a success.
“In letters to me in January and February, 1920,” says Bohr,
“Rutherford expressed his joy in Aston’s work,” which “gave such a
convincing confirmation of Rutherford’s atomic model.
”515 Of 281 naturally
occurring isotopes, over the next two decades Aston identified 212.
He
discovered that the weights of the atoms of all the elements he measured,
with the notable exception of hydrogen, were very nearly whole numbers,
which was a powerful argument in favor of the theory that the elements
were assembled in nature simply from protons and electrons—from
hydrogen atoms, that is.
Natural elements had not weighed up in whole
numbers for the chemists because they were oen mixtures of isotopes of
different whole-number weights.
Aston proved, for example, as he noted in a
later lecture, “that neon consisted, beyond doubt, of isotopes 20 and 22, and
that its atomic weight 20.2 was the result of these being present in the ratio
of about 9 to 1.
”516 at satisfied even J.
J.
omson.
But why was hydrogen an exception?
If the elements were built up from
hydrogen atoms, why did the hydrogen atom itself, the elemental building
block, weigh 1.008 alone?
Why did it then shrink to 4 when it was packed in
quartet as helium?
Why not 4.032 ?
And why was helium not exactly 4 but
4.002 , or oxygen not exactly 16 but 15.994 ?
What was the meaning of these
extremely small, and varying, differences from whole numbers?
Atoms do not fall apart, Aston reasoned.
Something very powerful holds
them together.
at glue is now called binding energy.
To acquire it,
hydrogen atoms packed together in a nucleus sacrifice some of their mass.
is mass defect is what Aston found when he compared the hydrogen atom
to the atoms of other elements following his whole-number rule.
In
addition, he said, nuclei may be more or less loosely packed.
e density of
their packing requires more or less binding energy, and that in turn requires
more or less mass: hence the small variations.
e difference between the
measured mass and the whole number he expressed as a fraction, the
packing fraction: roughly, the divergence of an element from its whole
number divided by its whole number.
“High packing fractions,” Aston
proposed, “indicate looseness of packing, and therefore low stability: low
packing fractions the reverse.” 517 He plotted the packing fractions on a
graph and demonstrated that the elements in the broad middle of the
periodic table—nickel, iron, tin, for example—had the lowest packing
fractions and were therefore the most stable, while elements at the extremes
of the periodic table—hydrogen at the light end, for example, uranium at the
heavy—had high packing fractions and were therefore the most unstable.
Locked within all the elements, he said, but most unstably so in the case of
those with high packing fractions, was mass converted to energy.
Comparing helium to hydrogen, nearly 1 percent of the hydrogen mass was
missing (4 divided by 4.032 =.992 = 99.2 %).
“If we were able to transmute
[hydrogen] into [helium] nearly 1 percent of the mass would be annihilated.
On the relativity equivalence of mass and energy now experimentally proved
[Aston refers here to Einstein’s famous equation E = mc 2], the quantity of
energy liberated would be prodigious.
us to change the hydrogen in a
glass of water into helium would release enough energy to drive the ‘Queen
Mary’ across the Atlantic and back at full speed.” 518
Aston goes on in this lecture, delivered in 1936, to speculate about the
social consequences of that energy release.
Armed with the necessary
knowledge, he says, “the nuclear chemists, I am convinced, will be able to
synthesise elements just as ordinary chemists synthesise compounds, and it
may be taken as certain that in some reactions sub-atomic energy will be
liberated.” And, continuing:519
ere are those about us who say that such research should be stopped by
law, alleging that man’s destructive powers are already large enough.
So,
no doubt, the more elderly and ape-like of our prehistoric ancestors
objected to the innovation of cooked food and pointed out the grave
dangers attending the use of the newly discovered agency, fire.
Personally
I think there is no doubt that sub-atomic energy is available all around us,
and that one day man will release and control its almost infinite power.
We cannot prevent him from doing so and can only hope that he will not
use it exclusively in blowing up his next door neighbor.
e mass-spectrograph Francis Aston invented in 1919 could not release
the binding energy of the atom.
But with it he identified that binding energy
and located the groups of elements which in their comparative instability
might be most likely to release it if suitably addressed.
He was awarded the
Nobel Prize in Chemistry in 1922 for his work.
Aer accepting the award
alongside Niels Bohr—“Stockholm has been the city of our dreams ever
since,” his sister, who regularly traveled with him, reminisces—he returned
to the Cavendish to build larger and more accurate mass-spectrographs,
operating them habitually at night because he “particularly detested,” his
sister says, “various human noises,” including even conversations muffled
through the walls of his rooms.520 “He was very fond of animals, especially
cats and kittens, and would go to any amount of trouble to make their
acquaintance, but he didn’t like dogs of the barking kind.” 521 Although
Aston respected Ernest Rutherford enormously, the Cavendish director’s
great boom must ever have been a trial.
* * *
e United States led the way in particle acceleration.
e American
mechanical tradition that advanced the factory and diversified the armory
now extended into the laboratory as well.
A congressman in 1914 had
questioned a witness at an appropriations hearing, “What is a physicist?
I
was asked on the floor of the House what in the name of common sense a
physicist is, and I could not answer.” 522 But the war made evident what a
physicist was, made evident the value of science to the development of
technology, including especially military technology, and government
support and the support of private foundations were immediately
forthcoming.
Twice as many Americans became physicists in the dozen
years between 1920 and 1932 as had in the previous sixty.
ey were better
trained than their older counterparts, at least fiy of them in Europe on
National Research Council or International Education Board or the new
Guggenheim fellowships.
By 1932 the United States counted about 2,500
physicists, three times as many as in 1919.
e Physical Review, the journal
that has been to American physicists what the Zeitschri für Physik is to
German, was considered a backwater publication, if not a joke, in Europe
before the 1920s.
It thickened to more than twice its previous size in that
decade, increased in 1929 to biweekly publication, and began to find readers
in Cambridge, Copenhagen, Göttingen and Berlin eager to scan it the
moment it arrived.
Psychometricians have closely questioned American scientists of this first
modern generation, curious to know what kind of men they were—there
were few women among them—and from what backgrounds they
emerged.
523 Small liberal arts colleges in the Middle West and on the Pacific
coast, one study found, were most productive of scientists then (by contrast,
New England in the same period excelled at the manufacture of lawyers).
Half the experimental physicists studied and fully 84 percent of the
theoreticians were the sons of professional men, typically engineers,
physicians and teachers, although a minority of experimentalists were
farmers’ sons.
None of the fathers of the sixty-four scientists, including
twenty-two physicists, in the largest of these studies was an unskilled
laborer, and few of the fathers of physicists were businessmen.
e physicists
were almost all either first-born sons or eldest sons.
eoretical physicists
averaged the highest verbal IQ’s among all scientists studied, clustering
around 170, almost 20 percent higher than the experimentalists.
524
eoreticians also averaged the highest spatial IQ’s, experimentalists ranking
second.
e sixty-four-man study which included twenty-two physicists among its
“most eminent scientists in the U.S.” produced this composite portrait of the
American scientist in his prime:
He is likely to have been a sickly child or to have lost a parent at an early
age.
He has a very high I.Q.
and in boyhood began to do a great deal of
reading.
He tended to feel lonely and “different” and to be shy and aloof
from his classmates.
He had only a moderate interest in girls and did not
begin dating them until college.
He married late...
has two children and
finds security in family life; his marriage is more stable than the average.
Not until his junior or senior year in college did he decide on his vocation
as a scientist.
What decided him (almost invariably) was a college project
in which he had occasion to do some independent research—to find out
things for himself.
Once he discovered the pleasures of this kind of work,
he never turned back.
He is completely satisfied with his chosen
vocation....
He works hard and devotedly in his laboratory, oen seven
days a week.
He says his work is his life, and he has few recreations....
e movies bore him.
He avoids social affairs and political activity, and
religion plays no part in his life or thinking.
Better than any other interest
or activity, scientific research seems to meet the inner need of his
nature.525
Clearly this is close to Robert Oppenheimer.
e group studied, like the
American physics community then, was predominantly Protestant in origin
with a disproportionate minority of Jews and no Catholics.
A psychological examination of scientists at Berkeley, using Rorschach
and ematic Apperception Tests as well as interviews, included six
physicists and twelve chemists in a total group of forty.
526 It found that
scientists think about problems in much the same way artists do.
Scientists
and artists proved less similar in personality than in cognition, but both
groups were similarly different from businessmen.
Dramatically and
significantly, almost half the scientists in this study reported themselves to
have been fatherless as children, “their fathers dying early, or working away
from home, or remaining so aloof and nonsupportive that their sons
scarcely knew them.” 527 ose scientists who grew up with living fathers
described them as “rigid, stern, aloof, and emotionally reserved.” 528 (A
group of artists previously studied was similarly fatherless; a group of
businessmen was not.)
Oen fatherless and “shy, lonely,” writes the psychometrician Lewis M.
Terman, “slow in social development, indifferent to close personal
relationships, group activities or politics,” these highly intelligent young men
found their way into science through a more personal discovery than the
regularly reported pleasure of independent research.529 Guiding that
research was usually a fatherly science teacher.
530 Of the qualities that
distinguished this mentor in the minds of his students, not teaching ability
but “masterfulness, warmth and professional dignity” ranked first.531 One
study of two hundred of these mentors concludes: “It would appear that the
success of such teachers rests mainly upon their capacity to assume a father
role to their students.
”532 e fatherless young man finds a masterful
surrogate father of warmth and dignity, identifies with him and proceeds to
emulate him.
In a later stage of this process the independent scientist works
toward becoming a mentor of historic stature himself.
e man who would found big-machine physics in America arrived at
Berkeley one year before Oppenheimer, in 1928.
Ernest Orlando Lawrence
was three years older than the young theoretician and in many ways his
opposite, an extreme of the composite American type.
533 Both he and
Oppenheimer were tall and both had blue eyes and high expectations.
But
Ernest Lawrence was an experimentalist, from prairie, small-town South
Dakota; of Norwegian stock, the son of a superintendent of schools and
teachers’ college president; domestically educated through the Ph.D.
at the
Universities of South Dakota, Minnesota and Chicago and at Yale; with
“almost an aversion to mathematical thought” according to one of his
protégés, the later Nobel laureate Luis W.
Alvarez; a boyish extrovert whose
strongest expletives were “Sugar!” and “Oh fudge!” who learned to stand at
ease among the empire builders of patrician California’s Bohemian Grove; a
master salesman who paid his way through college peddling aluminum
kitchenware farm to farm; with a gi for inventing ingenious machines.534
Lawrence arrived at Berkeley from Yale in a Reo Flying Cloud with his
parents and his younger brother in tow and put up at the faculty club.
Fired
compulsively with ambition—for physics, for himself—he worked from
early morning until late at night.
As far back as his first year of graduate school, 1922, Lawrence had begun
to think about how to generate high energies.
His flamboyant, fatherly
mentor encouraged him.
William Francis Gray Swann, an Englishman who
had found his way to Minnesota via the Department of Terrestrial
Magnetism of the District of Columbia’s private Carnegie Institution, took
Lawrence along with him first to Chicago and then to Yale as he moved up
the academic ladder himself.
Aer Lawrence earned his Ph.D.
and a
promising reputation Swann convinced Yale to jump him over the
traditional four years of instructorship to a starting position as assistant
professor of physics.
Swann’s leaving Yale in 1926 was one reason Lawrence
had decided to move West, that and Berkeley’s offer of an associate
professorship, a good laboratory, as many graduate-student assistants as he
could handle and $3,300 a year, an offer Yale chose not to match.
At Berkeley, Lawrence said later, “it seemed opportune to review my plans
for research, to see whether I might not profitably go into nuclear research,
for the pioneer work of Rutherford and his school had clearly indicated that
the next great frontier for the experimental physicist was surely the atomic
nucleus.
”535 But as Luis Alvarez explains, “the tedious nature of Rutherford’s technique...
repelled most prospective nuclear physicists.
Simple
calculations showed that one microampere of electrically accelerated light
nuclei would be more valuable than the world’s total supply of radium—if
the nuclear particles had energies in the neighborhood of a million electron
volts.” 536
Alpha particles or, better, protons could be accelerated by generating them
in a discharge tube and then repelling or attracting them electrically.
But no
one knew how to confine in one place for any useful length of time, without
electrical breakdown from sparking or overheating, the million volts that
seemed to be necessary to penetrate the electrical barrier of the heavier
nuclei.
e problem was essentially mechanical and experimental; not
surprisingly, it attracted the young generation of American experimental
physicists who had grown up in small towns and on farms experimenting
with radio.
By 1925 Lawrence’s boyhood friend and Minnesota classmate
Merle Tuve, another protégé of W.
F.
G.
Swann now installed at the Carnegie
Institution and working with three other physicists, had managed brief but
impressive accelerations with a high-voltage transformer submerged in oil;
others, including Robert J.
Van de Graaff at MIT and Charles C.
Lauritsen at
Caltech, were also developing machines.
Lawrence pursued more promising studies but kept the high-energy
problem in mind.
e essential vision came to him in the spring of 1929,
four months before Oppenheimer arrived.
“In his early bachelor days at
Berkeley,” writes Alvarez, “Lawrence spent many of his evenings in the
library, reading widely....
Although he passed his French and German
requirements for the doctor’s degree by the slimmest of margins, and
consequently had almost no facility with either language, he faithfully leafed
through the back issues of the foreign periodicals, night aer night.” 537 Such
was the extent of Lawrence’s compulsion.
It paid.
He was skimming the
German Arkiv für Elektrotechnik, an electrical-engineering journal physicists
seldom read, and happened upon a report by a Norwegian engineer named
Rolf Wideröe, Über ein neues Prinzip zur Herstellung hoher Spannungen: “On
a new principle for the production of higher voltages.” e title arrested him.
He studied the accompanying photographs and diagrams.
ey explained
enough to set Lawrence off and he did not bother to struggle through the
text.
Wideröe, elaborating on a principle established by a Swedish physicist in
1924, had found an ingenious way to avoid the high-voltage problem.
He
mounted two metal cylinders in line, attached them to a voltage source and
evacuated them of air.
e voltage source supplied 25,000 volts of high-
frequency alternating current, current that changed rapidly from positive to
negative potential.
at meant it could be used both to push and to pull
positive ions.
Charge the first cylinder negatively to 25,000 volts, inject
positive ions into one end, and the ions would be accelerated to 25,000 volts
as they le the first cylinder for the second.
Alternate the charge then—
make the first cylinder positive and the second cylinder negative—and the
ions would be pushed and pulled to further acceleration.
Add more
cylinders, each one longer than the last to allow for the increasing speed of
the ions, and theoretically you could accelerate them further still, until such
a time as they scattered too far outward from the center and crashed into the
cylinder walls.
Wideröe’s important innovation was the use of a relatively
small voltage to produce increasing acceleration.
“is new idea,” says
Lawrence, “immediately impressed me as the real answer which I had been
looking for to the technical problem of accelerating positive ions, and
without looking at the article further I then and there made estimates of the
general features of a linear accelerator for protons in the energy range above
one million [volts].” 538
Lawrence’s calculations momentarily discouraged him.
e accelerator
tube would be “some meters in length,” too long, he thought, for the
laboratory.
(Linear accelerators today range in length up to two miles.) “And
accordingly, I asked myself the question, instead of using a large number of
cylindrical electrodes in line, might it not be possible to use two electrodes
over and over again by sending the positive ions back and forth through the
electrodes by some sort of appropriate magnetic field arrangement.” e
arrangement he conceived was a spiral.
“It struck him almost immediately,”
Alvarez later wrote, “that one might ‘wind up’ a linear accelerator into a
spiral accelerator by putting it in a magnetic field,” because the magnetic
lines of force in such a field guide the ions.
539 Given a welltimed push, they
would swing around in a spiral, the spiral becoming larger as the particles
accelerated and were thus harder to confine.
en, making a simple
calculation for the magnetic-field effects, Lawrence uncovered an
unsuspected advantage to a spiral accelerator: in a magnetic field slow
particles complete their smaller circuits in exactly the same time faster
particles complete their larger circuits, which meant they could all be
accelerated together, efficiently, with each alternating push.
Exuberantly Lawrence ran off to tell the world.
An astronomer who was
still awake at the faculty club was draed to check his mathematics.
He
shocked one of his graduate students the next day by bombarding him with
the mathematics of spiral accelerations but mustering no interest whatever
in his thesis experiment.
“Oh, that,” Lawrence told the questioning student.
“Well, you know as much on that now as I do.
Just go ahead on your
own.
”540 A faculty wife crossing the campus the next evening heard a
startling “I’m going to be famous!” as the young experimentalist burst past
her on the walk.541
Lawrence then traveled East to a meeting of the American Physical
Society and discovered that not many of his colleagues agreed.
To less
inspired mechanicians the scattering problem looked insurmountable.
Merle
Tuve was skeptical.
Jesse Beams, a Yale colleague and a close friend, thought
it was a great idea if it worked.
Despite Lawrence’s reputation as a go-getter
—perhaps because no one encouraged him, perhaps because the idea was
solid and sure in his head but the machine on the laboratory bench might
not be—he kept putting off building his spiral particle accelerator.
He was
not the first man of ambition to find himself stalling on the summit ridge of
a famous future.
Oppenheimer arrived in a battered gray Chrysler in the late summer of
1929 from another holiday at the Sangre de Cristos ranch with Frank—the
ranch was named Perro Caliente now, “hot dog,” Oppenheimer’s cheer when
he had learned the property could be leased.542 He put up at the faculty club
and the two opposite numbers, he and Lawrence, became close friends.
Oppenheimer saw “unbelievable vitality and love of life” in Lawrence.
“Work
all day, run off for tennis, and work half the night.
His interest was so
primarily active [and] instrumental and mine just the opposite.” 543 ey
rode horses together, Lawrence in jodhpurs and using an English saddle in
the American West—to distance himself, Oppenheimer thought, from the
farm.
When Lawrence could get away they went off on long recreational
drives in the Reo to Yosemite and Death Valley.
A distinguished experimentalist from the University of Hamburg, Otto
Stern, a Breslau Ph.D., forty-one that year and on his way to a Nobel Prize
(though Lawrence would beat him), gave Lawrence the necessary boost.
Sometime aer the Christmas holidays the two men dined out in San
Francisco, a pleasant ferry ride across the unbridged bay.
Lawrence
rehearsed again his practiced story of particles spinning to boundless
energies in a confining magnetic field, but instead of coughing politely and
changing the subject, as so many other colleagues had done, Stern produced
a Germanic duplicate of Lawrence’s original enthusiasm and barked at him
to leave the restaurant immediately and go to work.
Lawrence waited in
decency until morning, cornered one of his graduate students and
committed him to the project as soon as he had finished studying for his
Ph.D.
exam.
e machine that resulted looked, in top and side views, like this:
e two cylinders of the Wideröe accelerator have become two brass
electrodes shaped like the cut halves of a cylindrical flask.
ese are
contained completely within a vacuum tank and the vacuum tank is
mounted between the round, flat poles of a large electromagnet.
In the space between the two electrodes (which came to be called dees
because of their shape), at the center point, a hot filament and an outlet for
hydrogen gas work together to produce protons which stream off into the
magnetic field.
e two dees, alternately charged, push and pull the protons
as they come around.
When they have been accelerated through about a
hundred spirals the particles exit in a beam which can then be directed onto
a target.
With a 4.5 -inch chamber and with less than 1,000 volts on the dees,
on January 2, 1931, Lawrence and his student M.
Stanley Livingston
produced 80,000-volt protons.
e scattering problem solved itself at low accelerations when Livingston
thought to remove the fine grid of wires installed in the gap between the
dees that kept the accelerating electric field out of the dri space inside.
e
electric fields between the dee edges suddenly began functioning as lenses,
focusing the spiraling particles by deflecting them back toward the middle
plane.
“e intensity then became a hundred times what it was before,”
Livingston says.544 at effect was too weak to confine the higher-speed
particles.
Livingston turned his attention to magnetic confinement.
He
suspected the particle beam lost focus at higher speeds because the pole
faces of the magnet were not completely true, a lack of uniformity which in
turn caused irregularities in the magnetic field.
Impulsively he cut sheets of
iron foil into small shims “having a shape much like an exclamation point,”
as Lawrence and he would write in the Physical Review, and inserted the
shims by trial and error between the pole faces and the vacuum chamber.545
us tuning the magnetic field “increased the amplification factor...
from
about 75 to about 300”— Lawrence added these triumphant italics.
With
both electric and magnetic focusing, in February 1932 an eleven-inch
machine produced million-volt protons.
It had a nickname by then that
Lawrence would make official in 1936: cyclotron.
Even in the formal
scientific report to the Physical Review on April 1, 1932, he was unable to
contain his enthusiasm for the new machine’s possibilities:
Assuming then a voltage amplification of 500, the production of
25,000,000 volt-protons [!] would require 50,000 volts at a wave-length of
14 meters applied across the accelerators; thus, 25,000 volts on each
accelerator with respect to ground.
It does appear entirely feasible to do
this.
546
e magnet for that one would weigh eighty tons, heavier than any machine
used in physics up to that time.
Lawrence, now a full professor, was already
raising funds.
* * *
In his graduate-student days in Europe Robert Oppenheimer told a friend
that he dreamed of founding a great school of theoretical physics in the
United States—at Berkeley, as it happened, the second desert aer New
Mexico that he chose to colonize.
547 Ernest Lawrence seems to have
dreamed of founding a great laboratory.
Both men coveted success and, each
in his own way, the rewards of success, but they were differently driven.
Oppenheimer’s youthful preciosity matured in Europe and the early
Berkeley years into refinement that was usually admirable if still sometimes
exquisite.
Oppenheimer craed that persona for himself at least in part from
a distaste for vulgarity that probably originated in rebellion against his
entrepreneurial father and that was not without elements of anti-Semitic
self-hatred.
Along the way he convinced himself that ambition and worldly
success were vulgar, a conviction bolstered nicely by trust fund earnings to
the extent of ten thousand dollars a year.
ereby he confounded his own
strivings.
e American experimental physicist I.
I.
Rabi would later
question why “men of Oppenheimer’s gis do not discover everything worth
discovering.” 548 His answer addresses one possible source of limitation:
It seems to me that in some respects Oppenheimer was overeducated in
those fields which lie outside the scientific tradition, such as his interest in
religion, in the Hindu religion in particular, which resulted in a feeling for
the mystery of the universe that surrounded him almost like a fog.
He saw
physics clearly, looking toward what had already been done, but at the
border he tended to feel that there was much more of the mysterious and
novel than there actually was....
Some may call it a lack of faith, but in
my opinion it was more a turning away from the hard, crude methods of
theoretical physics into a mystical realm of broad intuition.
But Oppenheimer’s revulsion from what he considered vulgar, from just
those “hard, crude methods” to which Rabi refers, must have been another
and more directly punishing confusion.
His elegant physics, so far as an
outsider can tell—his scientific papers are nearly impenetrable to the
nonmathematician and deliberately so—is a physics of bank shots.
It works
the sides and the corners and uses the full court but prefers not to drive
relentlessly for the goal.
Wolfgang Pauli and the hard, distant Cambridge
theoretician Paul A.
M.
Dirac, Eugene Wigner’s brother-in-law, both
mathematicians of formidable originality, were his models.
Oppenheimer
first described the so-called tunnel effect whereby an uncertainly located
particle sails through the electrical barrier around the nucleus on a light
breeze of probability, existing—in particle terms—then ceasing to exist, then
instantly existing again on the other side.549 But George Gamow, the antic
Russian, lecturing in Cambridge, devised the tunnel-effect equations that
the experimenters used.
Hans Bethe in the late 1930s first defined the
mechanisms of carbon-cycle thermonuclear burning that fire the stars, work
which won for him the Nobel Prize; Oppenheimer looked into the subtleties
of the invisible cosmic margins, modeled the imploding collapse of dying
suns and described theoretical stellar objects that would not be discovered
for thirty and forty years—neutron stars, black holes—because the
instruments required to detect them, radio telescopes and X-ray satellites,
had not been invented yet.
550 (Alvarez believes if Oppenheimer had lived
long enough to see these developments he would have won a Nobel Prize for
his work.) at was originality not so much ahead of its time as outside the
frame.
Some of this psychological and creative convolution winds through a
capsule essay on the virtues of discipline that Oppenheimer composed
within a letter to his brother Frank in March 1932, when he was not quite
twenty-eight years old.
It is worth copying out at length; it hints of the long,
self-punishing penance he expected to serve to cleanse any stain of crudity
from his soul:
You put a hard question on the virtue of discipline.
What you say is true: I
do value it—and I think that you do too—more than for its earthly fruit,
proficiency.
I think that one can give only a metaphysical ground for this
evaluation; but the variety of metaphysics which gave an answer to your
question has been very great, the metaphysics themselves very disparate:
the bhagavad gita, Ecclesiastes, the Stoa, the beginning of the Laws, Hugo
of St Victor, St omas, John of the Cross, Spinoza.
is very great
disparity suggests that the fact that discipline is good for the soul is more
fundamental than any of the grounds given for its goodness.
I believe that
through discipline, though not through discipline alone, we can achieve
serenity, and a certain small but precious measure of freedom from the
accidents of incarnation, and charity, and that detachment which
preserves the world which it renounces.
I believe that through discipline
we can learn to preserve what is essential to our happiness in more and
more adverse circumstances, and to abandon with simplicity what would
else have seemed to us indispensable; that we come a little to see the world
without the gross distortion of personal desire, and in seeing it so, accept
more easily our earthly privation and its earthly horror—But because I
believe that the reward of discipline is greater than its immediate
objective, I would not have you think that discipline without objective is
possible: in its nature discipline involves the subjection of the soul to
some perhaps minor end; and that end must be real, if the discipline is not
to be factitious.
erefore I think that all things which evoke discipline:
study, and our duties to men and to the commonwealth, war, and personal
hardship, and even the need for subsistence, ought to be greeted by us
with profound gratitude, for only through them can we attain to the least
detachment; and only so can we know peace.
551
Lawrence, orders of magnitude less articulate than Oppenheimer, was also
fiercely driven; the question is what drove him.
A paragraph from a letter to
his brother John, written at about the same time as Oppenheimer’s essay, is
revealing: “Interested to hear you have had a period of depression.
I have
them oen—sometimes nothing seems to be OK—but I have gotten used to
them now.
I expect the blues and I endure them.
Of course the best palliative
is work, but sometimes it is hard to work under the circumstances.
”552 at
work is only a “palliative,” not a cure, hints at how blue the blues could be.
Lawrence was a hidden sufferer, in some measure manicdepressive; he kept
moving not to fall in.
To all these emotional troublings—Oppenheimer’s and Lawrence’s, as
Bohr’s and others’ before and since—science offered an anchor: in discovery
is the preservation of the world.
e psychologist who studied scientists at
Berkeley with Rorschach and TAT found that “uncommon sensitivity to
experiences—usually sensory experiences” is the beginning of creative
discovery in science.
“Heightened sensitivity is accompanied in thinking by
overalertness to relatively unimportant or tangential aspects of problems.
It
makes [scientists] look for and postulate significance in things which
customarily would not be singled out.
It encourages highly individualized
and even autistic ways of thinking.
”553 Consider Rutherford playing his
thoroughly unlikely hunch about alpha backscattering, Heisenberg
remembering an obscure remark of Einstein’s and concluding that nature
only performed in consonance with his mathematics, Lawrence flipping
compulsively through obscure foreign journals:
Were this thinking not in the framework of scientific work, it would be
considered paranoid.
In scientific work, creative thinking demands seeing
things not seen previously, or in ways not previously imagined; and this
necessitates jumping off from “normal” positions, and taking risks by
departing from reality.
e difference between the thinking of the
paranoid patient and the scientist comes from the latter’s ability and
willingness to test out his fantasies or grandiose conceptualizations
through the systems of checks and balances science has established—and
to give up those schemes that are shown not to be valid on the basis of
these scientific checks.
It is specifically because science provides such a
framework of rules and regulations to control and set bounds to paranoid
thinking that a scientist can feel comfortable about taking the paranoid
leaps.
Without this structuring, the threat of such unrealistic, illogical,
and even bizarre thinking to overall thought and personality organization
in general would be too great to permit the scientist the freedom of such
fantasying.554
At the leading edges of science, at the threshold of the truly new, the threat
has oen nearly overwhelmed.
us Rutherford’s shock at rebounding alpha
particles, “quite the most incredible event that has ever happened to me in
my life.” us Heisenberg’s “deep alarm” when he came upon his quantum
mechanics, his hallucination of looking through “the surface of atomic
phenomena” into “a strangely beautiful interior” that le him giddy.
us
also, in November 1915, Einstein’s extreme reaction when he realized that
the general theory of relativity he was painfully developing in the isolation
of his study explained anomalies in the orbit of Mercury that had been a
mystery to astronomers for more than fiy years.
e theoretical physicist
Abraham Pais, his biographer, concludes: “is discovery was, I believe, by
far the strongest emotional experience in Einstein’s scientific life, perhaps in
all his life.
Nature had spoken to him.
He had to be right.
‘For a few days, I
was beside myself with joyous excitement.’ Later, he told [a friend] that his
discovery had given him palpitations of the heart.
What he told [another
friend] is even more profoundly significant: when he saw that his
calculations agreed with the unexplained astronomical observations, he had
the feeling that something actually snapped in him.” 555
e compensation for such emotional risk can be enormous.
For the
scientist, at exactly the moment of discovery—that most unstable existential
moment—the external world, nature itself, deeply confirms his innermost
fantastic convictions.
Anchored abruptly in the world, Leviathan gasping on
his hook, he is saved from extreme mental disorder by the most profound
affirmation of the real.
Bohr especially understood this mechanism and had the courage to turn it
around and use it as an instrument of assay.
Otto Frisch remembers a
discussion someone attempted to deflect by telling Bohr it made him giddy,
to which Bohr responded: “But if anybody says he can think about quantum
problems without getting giddy, that only shows that he has not understood
the first thing about them.” 556 Much later, Oppenheimer once told an
audience, Bohr was listening to Pauli talking about a new theory on which
he had recently been attacked.
“And Bohr asked, at the end, ‘Is this really
crazy enough?
e quantum mechanics was really crazy.’ And Pauli said, ‘I
hope so, but maybe not quite.’ ” 557 Bohr’s understanding of how crazy
discovery must be clarifies why Oppenheimer sometimes found himself
unable to push alone into the raw original.
To do so requires a sturdiness at
the core of identity—even a brutality—that men as different as Niels Bohr
and Ernest Lawrence had earned or been granted that he was unlucky
enough to lack.
It seems he was cut out for other work: for now, building
that school of theoretical physics he had dreamed of.
* * *
On June 3, 1920, Ernest Rutherford delivered the Bakerian Lecture before
the Royal Society of London.558 It was the second time he had been invited
to fill the distinguished lectureship.
He used the occasion to sum up present
understanding of the “nuclear constitution” and to discuss his successful
transmutation of the nitrogen atom reported the previous year, the usual
backward glance of such formal public events.
But unusually and presciently,
he also chose to speculate about the possibility of a third major constituent
of atoms besides electrons and protons.
He spoke of “the possible existence
of an atom of mass 1 which has zero nucleus charge.” Such an atomic
structure, he thought, seemed by no means impossible.
It would not be a
new elementary particle, he supposed, but a combination of existing
particles, an electron and a proton intimately united, forming a single
neutral particle.
559
“Such an atom,” Rutherford went on with his usual perspicacity, “would
have very novel properties.
Its external [electrical] field would be practically
zero, except very close to the nucleus, and in consequence it should be able
to move freely through matter.
Its presence would probably be difficult to
detect by the spectroscope, and it may be impossible to contain it in a sealed
vessel.” ose might be its peculiarities.
is would be its exceptional use:
“On the other hand, it should enter readily the structure of atoms, and may
either unite with the nucleus or be disintegrated by its intense field.” A
neutral particle, if such existed— a neutron—might be the most effective of
all tools to probe the atomic nucleus.
Rutherford’s assistant James Chadwick attended this lecture and found
cause for disagreement.560 Chadwick was then twenty-nine years old.
He
had trained at Manchester and followed Rutherford down to Cambridge.
He
had accomplished much already—as a young man, two of his colleagues
write, his output “was hardly inferior to that of Moseley”—but he had sat out
the Great War in a German internment camp, to the detriment of his health
and to his everlasting boredom, and he was eager to move the new work of
nuclear physics along.
561 A neutral particle would be a wonder, but
Chadwick thought Rutherford had deduced it from flimsy evidence.
at winter he discovered his mistake.
Rutherford invited him to
participate in the work of extending the nitrogen transmutation results to
heavier elements.
Chadwick had improved scintillation counting by
developing a microscope that gathered more light and by tightening up
procedures.
He also knew chemistry and might help eliminate hydrogen as a
possible contaminant, a challenge to the nitrogen results that still bothered
Rutherford.
“But also, I think,” said Chadwick many years later in a
memoriallecture, “he wanted company to support the tedium of counting in
the dark—and to lend an ear to his robust rendering of ‘Onward, Christian
Soldiers.’ ”562
“Before the experiments,” Chadwick once told an interviewer, “before we
began to observe in these experiments, we had to accustom ourselves to the
dark, to get our eyes adjusted, and we had a big box in the room in which we
took refuge while Crowe, Rutherford’s personal assistant and technician,
prepared the apparatus.563 at is to say, he brought the radioactive source
down from the radium room, put it in the apparatus, evacuated it, or filled it
with whatever, put the various sources in and made the arrangements that
we’d agreed upon.
And we sat in this dark room, dark box, for perhaps half
an hour or so, and naturally, talked.” Among other things, they talked about
Rutherford’s Bakerian Lecture.
“And it was then that I realized that these
observations which I suspected were quite wrong, and which proved to be
wrong later on, had nothing whatever to do with his suggestion of the
neutron, not really.
He just hung the suggestion on to it.
Because it had been
in his mind for some considerable time.”
Most physicists had been content with the seemingly complete symmetry
of two particles, the electron and the proton, one negative, one positive.
Outside the atom—among the stripped, ionized matter beaming through a
discharge tube, for example—two elementary atomic constituents might be
enough.
But Rutherford was concerned with how each element was
assembled.
“He had asked himself,” Chadwick continues, “and kept on
asking himself, how the atoms were built up, how on earth were you going to
get—the general idea being at that time that protons and electrons were the
constituents of an atomic nucleus...
how on earth were you going to build
up a big nucleus with a large positive charge?
And the answer was a neutral
particle.”
From the lightest elements in the periodic table beyond hydrogen to the
heaviest, atomic number—the nucleus’ electrical charge and a count of its
protons—differed from atomic weight.
Helium’s atomic number was 2 but its
atomic weight was 4; nitrogen’s atomic number was 7 but its atomic weight
was 14; and the disparity increased farther along: silver, 47 but 107; barium,
56 but 137; radium, 88 but 226; uranium, 92 but 235 or 238.
eory at the
time proposed that the difference was made up by additional protons in the
nucleus closely associated with nuclear electrons that neutralized them.
But
the nucleus had a definite maximum size, well established by experiment,
and as elements increased in atomic number and atomic weight there
appeared to be less and less room in their nuclei for all the extra electrons.
e problem worsened with the development in the 1920s of quantum
theory, which made it clear that confining particles as light as electrons so
closely would require enormous energies, energies that ought to show up
when the nucleus was disturbed but never did.
e only evidence for the
presence of electrons in the nucleus was its occasional ejection of beta
particles, energetic electrons.
at was something to go on, but given the
other difficulties with packing electrons into the nucleus it was not enough.
“And so,” Chadwick concludes, “it was these conversations that convinced
me that the neutron must exist.
e only question was how the devil could
one get evidence for it....
It was shortly aer that I began to make
experiments on the side when I could.
[e Cavendish] was very busy, and
le me little time, and occasionally Rutherford’s interest would revive, but
only occasionally.
”564 Chadwick would search for the neutron with
Rutherford’s blessing, but the frustrating work of experiment was usually his
alone.
His temperament matched the challenge of discovering a particle that
might leave little trace of itself in its passage through matter; he was a shy,
quiet, conscientious, reliable man, something of a neutron himself.
Rutherford even felt it necessary to scold him for giving the boys at the
Cavendish too much attention, though Chadwick took their care and
nurturing to be his primary responsibility.
“It was Chadwick,” remembers
Mark Oliphant, “who saw that research students got the equipment they
needed, within the very limited resources of the stores and funds at his
disposal.” 565 If he seemed “dour and unsmiling” at first, with time “the
kindly, helpful and generous person beneath became apparent.” 566 He
tended, says Otto Frisch, “to conceal his kindness behind a gruff façade.” 567
e façade was protective.
James Chadwick was tall, wiry, dark, with a
high forehead, thin lips and a raven’s-beak nose.
“He had,” say his joint
biographers, colleagues both, “a deep voice and a dry sense of humour with
a characteristic chuckle.” 568 He was born in the village of Bollington, south
of Manchester in Cheshire, in 1891.
When he was still a small boy his father
le their country home to start a laundry in Manchester; Chadwick’s
grandmother seems to have raised him.
He sat for two scholarships to the
University of Manchester at sixteen, an early age even in the English
educational system, won them both, kept one and went off to the university.
He meant to read mathematics.
e entrance interviews were held
publicly in a large, crowded hall.
Chadwick got into the wrong line.
He had
already begun to answer the lecturer’s questions when he realized he was
being questioned for a physics course.
Since he was too timid to explain, he
decided that the physics lecturer impressed him and he would read for
physics.
e first year he was sorry, his biographers report: “the physics
classes were large and noisy.
”569 e second year he heard Rutherford lecture
on his early New Zealand experiments and was converted.
In his third year
Rutherford gave him a research project.
His timidity again confounded him,
this time almost fatally for his career: he discovered a snag in the procedure
Rutherford had recommended to him but could not bring himself to point it
out.
Rutherford thought he missed it.
Man and boy found their way past that
misunderstanding and Chadwick graduated from Manchester in 1911 with
first-class honors.
He stayed on for his master’s degree, working with A.
S.
Russell and
following the research in those productive years of Geiger, Marsden, de
Hevesy, Moseley, Darwin and Bohr.
In 1913, taking his M.Sc., he won an
important research scholarship that required him to change laboratories to
broaden his training.
By then Geiger had returned to Berlin; Chadwick
followed.
Which was a pleasure while it lasted—Geiger made a point of
introducing Chadwick around, so that he became acquainted with Einstein,
Hahn and Meitner, among others in Berlin—but the war intervened.
A reserve officer, Geiger was called up early.
He fortified Chadwick with a
personal check for two hundred marks before he le.
Some of the young
Englishman’s German friends advised him to leave the country quickly, but
others convinced him to wait to avoid the danger of encountering troop
trains along the way.
On August 2 Chadwick tried to buy a ticket home by
way of Holland at the Cook’s Tours office in Berlin.
Cook’s suggested going
through Switzerland instead.
at struck Chadwick’s friends as risky.
He
again accepted their advice and settled in to wait.
en it was too late.
He was arrested along with a German friend for
allegedly making subversive remarks—merely speaking English would have
done the job in those first weeks of hysterical nationalism—and languished
in a Berlin jail for ten days before Geiger’s laboratory arranged his release.
Once out he returned to the laboratory until chaos retreated behind order
again and the Kaiser’s government found time to direct that all Englishmen
in Germany be interned for the duration of the war.
e place of internment was a race track at Ruhleben—the name means
“quiet life”—near Spandau.
Chadwick shared with five other men a box stall
designed for two horses and must have thought of Gulliver.
In the winter he
had to stamp his feet till late morning before they thawed.
He and other
interns formed a scientific society and even managed to conduct
experiments.
Chadwick’s cold, hungry, quiet life at Ruhleben continued for
four interminable years.
is was the time, he said later, making the best of
it, when he really began to grow up.570 He returned to Manchester aer the
Armistice with his digestion ruined and £11 in his pocket.
He was at least
alive, unlike poor Harry Moseley.
Rutherford took him in.
Some of the experiments Chadwick conducted at the Cavendish in the
1920s to look for the neutron, he says, “were so desperate, so far-fetched as
to belong to the days of alchemy.
”571 He and Rutherford both thought of the
neutron, as Rutherford had imagined it in his Bakerian Lecture, as a close
union of proton and electron.
ey therefore conjured up various ways to
torture hydrogen—blasting it with electrical discharges, searching out the
effects on it of passing cosmic rays—in the hope that the H atom that had
been stable since the early days of the universe would somehow agree to
collapse into neutrality at their hands.
e neutral particle resisted their blandishments and the nucleus resisted
attack.
e laboratory, Chadwick remembers, “passed through a relatively
quiet spell.
Much interesting and important work was done, but it was work
of consolidation rather than of discovery; in spite of many attempts the
paths to new fields could not be found.” 572 It began to seem, he adds, that
“the problem of the new structure of the nucleus might indeed have to be
le to the next generation, as Rutherford had once said and as many
physicists continued to believe.
”573 Rutherford “was a little disappointed,
because it was so very difficult to find out anything really important.
”574
Quantum theory bloomed while nuclear studies stalled.
Rutherford had felt
optimistic enough in 1923 to shout at the annual meeting of the British
Association, “We are living in the heroic age of physics!” By 1927, in a paper
on atomic structure, he was a little less confident.
575 “We are not yet able to
do more than guess at the structure even of the lighter and presumably least
complex atoms,” he writes.
576 He proposed a structure nonetheless, with
electrons in the nucleus orbiting around nuclear protons, an atom within an
atom.
ey had other work.
In hindsight, it was necessary preparation.
e
scintillation method of detecting radiation had reached its limit of
effectiveness: it was unreliable if the counting rate was greater than 150 per
minute or less than about 3 per minute, and both ranges now came into view
in nuclear studies.
577 A disagreement between the Cavendish and the
Vienna Radium Institute convinced even Rutherford of the necessity of
change.
Vienna had reproduced the Cavendish’s light-element disintegration
experiments and published completely different results.
Worse, the Vienna
physicists attributed the discrepancy to inferior Cavendish equipment.
Chadwick laboriously reran the experiments with a specially made
microscope with zinc sulfide coated directly onto the lens of the
microscope’s objective, which greatly brightened the field.
e results
confirmed the Cavendish’s earlier count.
Chadwick then went to Vienna.
“He found,” write his biographers, “that the scintillation counting was done
by three young women—it was thought that not only did women have better
eyes than men but they were less likely to be distracted by thinking while
counting!” Chadwick observed the young women at work and realized that
because they understood what was expected of the experiments they
produced the expected results, unconsciously counting nonexistent
scintillations.578 To test the technicians he gave them, without explanation,
an unfamiliar experiment; this time their counts matched his own.
Vienna
apologized.
Hans Geiger, among others, turned back to the electrical counter he had
devised with Rutherford in 1908 and improved it.
e result, the Geiger
counter, was essentially an electrically charged wire strung inside a gas-filled
tube with a thinly covered window that allowed charged particles to enter.
Once inside the tube the charged particles ionized gas atoms; the electrons
thus stripped from the gas atoms were drawn to the positively charged wire;
that changed the current level in the wire; the change, in the form of an
electrical pulse, could then be run through an amplifier and converted to a
sound—typically a click—or shown as a jump in the sweep of a light beam
on the television-like screen of an oscilloscope.
e electrical counter could
operate continuously and could count above and below the limits possible to
fallible physicists peering at scintillation screens.
But the early counters had
a significant disadvantage: they were highly sensitive to gamma radiation,
much more so than zinc sulfide, and the radium compounds the Cavendish
used as alpha sources gave off plentiful gamma rays.
Polonium, the
radioactive element that Marie Curie had discovered in 1898 and named
aer her native Poland, could be an excellent alternative.
It was a good alpha
source and with a gamma-ray background 100,000 times less intense than
radium it was much less likely to overload an electrical counter.
Unfortunately, polonium was difficult to acquire.
A ton of uranium ore
contained only about 0.1 gram, too little for commercial separation.
It was
available practically only as a byproduct of the radioactive decay of radium,
and radium too was scarce.
ere was time in those years to recover from the bleakness of the war
and get on with living.
In 1925 Chadwick married Aileen Stewart-Brown,
daughter of a family long established in business in Liverpool.
He had been
living at Gonville and Caius College; now he made plans for permanent
residence.
A year later, in the midst of house-building, when Rutherford
asked him and another Cavendish man to take on part of the work of
revising Rutherford’s old textbook on radioactivity, he fitted in the duty at
night, working bundled in an overcoat at a writing table moved close to the
fireplace of a dray temporary rental.
When the fire burned low he even
pulled on gloves.
At the end of the decade the Rutherfords suffered a personal tragedy.
eir daughter Eileen, twenty-nine years old and the mother of three
children—she was married to a theoretician, R.
H.
Fowler, who kept up that
end of physics at the Cavendish—gave birth to a fourth; one week later, on
December 23, she was felled by a lethal blood clot.
“e loss of his only
child,” writes A.
S.
Eve, “whom he loved and admired, aged Rutherford for a
time; he looked older and stooped more.
He continued his life and work
with a manful purpose, and one of the delights of his life was his group of
four grandchildren.
His face always lit up when he spoke of them.” 579
Rutherford was elevated to baron in the New Year’s Honours List of 1931,
the year he would turn sixty.
A kiwi crested his armorial bearings; they were
supported on the dexter side by a figure representing Hermes Trismegistus,
the Egyptian god of wisdom who was supposed to have written alchemical
books, and on the sinister side by a Maori holding a club; and the two
crossed curves that quartered his escutcheon traced the matched growth and
decay of activity that gives each radioactive element and isotope its
characteristic half-life.
580
Around 1928 a German physicist, Walther Bothe, “a real physicist’s
physicist” to Emilio Segrè, and Bothe’s student Herbert Becker began
studying the gamma radiation excited by alpha bombardment of light
elements.581 ey surveyed the light elements from lithium to oxygen as well
as magnesium, aluminum and silver.
Since they were concentrating on
gamma radiation excited from a target they wanted a minimum gamma
background and used a polonium radiation source.
“I don’t know how
[Bothe] got his sources,” Chadwick puzzles, “but he did.
”582 Lise Meitner had
generously sent polonium to Chadwick from the Kaiser Wilhelm Institutes,
but it was too little to allow Chadwick to do the work Bothe was doing.
e Germans found gamma excitation with boron, magnesium and
aluminum, as they had more or less expected, because alpha particles
disintegrate those elements, but they also and unexpectedly found it with
lithium and beryllium, which alphas in this reaction did not disintegrate.
“Indeed,” writes Norman Feather, one of Chadwick’s colleagues at the
Cavendish, “with beryllium, the intensity of the...
radiation was nearly ten
times as great as with any other element investigated.
”583 at was strange
enough; equally strange was the oddity that beryllium emitted this intense
radiation under alpha bombardment without emitting protons.
Bothe and
Becker reported their results briefly in August 1930, then more fully in
December.
e radiation they had excited from beryllium had more energy
than the bombarding alpha particles.
e principle of the conservation of
energy required a source for the excess; they proposed that it came from
nuclear disintegration despite the absence of protons.
Chadwick set one of his research students, an Australian named H.
C.
Webster, to work studying these unusual results.
A French team began the
same study a little later with better resources: Irene Curie, Mme.
Curie’s
somber and talented daughter, then thirty-three, and her husband Frédéric
Joliot, two years younger, a handsome, outgoing man trained originally as an
engineer whose charm reminded Segré of the French singer Maurice
Chevalier.
Marie Curie’s Radium Institute at the east end of the Rue Pierre Curie in
the Latin Quarter, built just before the war with funds from the French
government and the Pasteur Foundation, had the advantage in any studies
that required polonium.
Radon gas decays over time to three only mildly
radioactive isotopes: lead 210, bismuth 210 and polonium 210, which thus
become available for chemical separation.
Medical doctors throughout the
world then used radon sealed into glass ampules—“seeds”—for cancer
treatment.
When the radon decayed, which it did in a matter of days, the
seeds no longer served.
Many physicians sent them on to Paris as a tribute to
the woman who discovered radium.
ey accumulated to the world’s largest
source of polonium.
e Joliot-Curies had worked independently for the two years since their
marriage in 1927; in 1929 they decided to work in collaboration.
ey first
developed new chemical techniques for separating polonium, and by 1931
had purified a volume of the element almost ten times more intense than
any other existing source.
With their powerful new source they turned their
attention to the mystery of beryllium.
Chadwick’s student H.
C.
Webster had progressed in the meantime, by the
late spring of 1931, beyond recapitulation to discovery: he found, says
Chadwick, “that the radiation from beryllium which was emitted in the
same direction as the...
alpha-particles was more penetrating than the
radiation emitted in a backward direction.
”584 Gamma radiation, an
energetic form of light, should be emitted equally in every direction from a
point source such as a nucleus, just as visible light radiates equally from a
lightbulb filament.
A particle, on the other hand, would usually be bumped
forward by an incoming alpha.
“And that, of course,” Chadwick adds, “was a
point which excited me very much indeed, because I thought, ‘Here’s the
neutron.’ ”585
With twin daughters now, Chadwick had become a family man of regular
habits.
Among the most sacred of these was his annual June family vacation.
e possibility of finding his long-sought neutron was not sufficient cause to
change his plans.
It might have been, but he thought he needed a cloud
chamber for the next step in the search, and the one immediately available
to him at the Cavendish was not in working order.
He found a cloud
chamber in other hands; its owner agreed to help Webster use it when he
had finished using it himself.
Still assuming that the neutron was an
electron-proton doublet with enough residual electrical charge to ionize a
gas at least weakly, Chadwick wanted Webster to aim the beryllium
radiation into the cloud chamber and see if he could photograph its ionizing
tracks.
He le his student to the work and went off on holiday.
“Of course,” Chadwick said in retrospect of the neutron he was hunting
for, “they should not have seen anything” in the cloud chamber, nor did
they.
“ey wrote and told me what had happened, that they hadn’t found
anything, which disappointed me very much.” 586 When Webster moved on
to the University of Bristol, Chadwick decided to take over the beryllium
research himself.
First he had to shi his laboratory to a different part of the Cavendish
building, and that delayed him; then he had to prepare a strong polonium
source.
In the matter of polonium he was lucky.
Norman Feather had spent
the 1929–30 academic year in Baltimore, in the physics department at Johns
Hopkins, and there befriended an English physician who was in charge of
the radium supply at Baltimore’s Kelly Hospital.
e physician had stored
away several hundred used radon seeds; “together,” Feather remembers,
“they contained almost as much polonium as was available to Curie and
Joliot in Paris.” 587 e hospital donated them to the Cavendish and Feather
brought them home.
Chadwick accomplished the dangerous chemical
separation that autumn.
Irène Joliot-Curie reported her first results to the French Academy of
Sciences on December 28, 1931.
e beryllium radiation, she found, was
even more penetrating than Bothe and Becker had reported.
She
standardized her measurements and put the energy of the radiation at three
times the energy of the bombarding alpha particle.
e Joliot-Curies decided next to see if the beryllium radiation would
knock protons out of matter as alpha particles did.
“ey fitted their
ionization chamber with a thin window,” explains Feather, “and placed
various materials close to the window in the path of the radiation.
ey
found nothing, except with materials such as paraffin wax and cellophane
which already contained hydrogen in chemical combination.
When thin
layers of these substances were close to the window, the current in the
ionization chamber was greater than usual.
By a series of experimental tests,
both simple and elegant, they produced convincing evidence that this excess
ionization was due to protons ejected from the hydrogenous material.
”588
e Joliot-Curies understood then that what they were seeing were elastic
collisions—like the collisions of billiard balls or marbles—between the
beryllium radiation and the nuclei of H atoms.
But they were still committed to their previous conviction that the
penetrating radiation from beryllium was gamma radiation.
ey had not
thought about the possibility of a neutral particle.
ey had not read
Rutherford’s Bakerian Lecture because such lectures were invariably, in their
experience, only recapitulations of previously reported work.
Rutherford
and Chadwick alone had thought seriously about the neutron.
On January 18, 1932, the Joliot-Curies reported to the Academy of
Sciences their discovery that paraffin wax emitted high-velocity protons
when bombarded by beryllium radiation.
But that was not the title and the
argument of the paper they wrote.
ey titled their paper “e emission of
protons of high velocity from hydrogenous materials irradiated with very
penetrating gamma rays.” Which was as unlikely as if a marble should
deflect a wrecking ball.
Gamma rays could deflect electrons, a phenomenon
known as the Compton effect aer its discoverer, the American
experimental physicist Arthur Holly Compton, but a proton is 1,836 times
heavier than an electron and not easily moved.
At the Cavendish in early February Chadwick found the Comptes Rendus,
the French physics journal, in his morning mail, discovered the Joliot-Curie
paper and read it with widening eyes:
Not many minutes aerward Feather came to my room to tell me about
this report, as astonished as I was.
A little later that morning I told
Rutherford.
It was a custom of long standing that I should visit him about
11 a.m.
to tell him any news of interest and to discuss the work in
progress in the laboratory.
As I told him about the Curie-Joliot
observation and their views on it, I saw his growing amazement; and
finally he burst out “I don’t believe it.” Such an impatient remark was
utterly out of character, and in all my long association with him I recall no
similar occasion.
I mention it to emphasize the electrifying effect of the
Curie-Joliot report.
Of course, Rutherford agreed that one must believe
the observations; the explanation was quite another matter.589
No further duty interposed itself between Chadwick and his destiny.
He
went fervently to work, starting on February 7, 1932, a Sunday: “It so
happened that I was just ready to begin experiment [when he read of the
Joliot-Curie discovery]....
I started with an open mind, though naturally
my thoughts were on the neutron.
I was reasonably sure that the CurieJoliot
observations could not be ascribed to a kind of Compton effect, for I had
looked for this more than once.
I was convinced that there was something
quite new as well as strange.”
His simple apparatus consisted of a radiation source and an ionization
chamber, the chamber connected to a vacuum-tube amplifier and thence to
an oscilloscope.
e radiation source, an evacuated metal tube strapped to a
rough-sawn block of pine, contained a one-centimeter silver disk coated
with polonium mounted close behind a two-centimeter disk of pure
beryllium, a silver-gray metal that is three times as light as aluminum.
590
Alpha particles from the polonium striking beryllium nuclei knocked out
the penetrating beryllium radiation, which, Chadwick found immediately,
would pass essentially unimpeded through as much as two centimeters of
lead.
e half-inch opening into the small ionization chamber that faced this
radiation source was covered with aluminum foil.
Within the shallow
chamber, in an atmosphere of air at normal pressure, a small charged plate
collected electrons ionized by incoming radiation and moved their pulses
along to the amplifier and oscilloscope.
“For the purpose at hand,” explains
Norman Feather, “such an arrangement was ideal.
If the amplifier were
carefully designed, it was possible to ensure that the magnitude of the
oscillograph deflection was directly proportional to the amount of
ionization produced in the chamber....
e energy of the recoil atom
producing the ionization could thus be calculated directly from the size of
the deflection on the oscillograph record.” 591
Chadwick mounted a sheet of paraffin two millimeters thick in front of
the aluminum-foil window into the ionization chamber; immediately, he
wrote in his final report on the experiment, “the number of deflections
recorded by the oscillograph increased markedly.” at showed that particles
ejected from the paraffin were entering the chamber.
en he began
interposing sheets of aluminum foil between the wax and the chamber
window until no more kicks appeared on the oscilloscope; by scaling the
absorptions of aluminum compared to air he calculated the range of the
particles as just over 40 centimeters in air; that range meant “it was obvious
that the particles were protons.
”592
us repeating the Joliot-Curie work prepared the way.
Now Chadwick
broke new ground.
He removed the paraffin sheet.
He wanted to study what
happens to other elements bombarded directly by the beryllium radiation.
Elements in the form of solids he mounted in front of the chamber window:
“In this way lithium, beryllium, boron, carbon and nitrogen, as
paracyanogen, were tested.
”593 Elements in the form of gases he simply
pumped into the chamber to replace the ambient air: “Hydrogen, helium,
nitrogen, oxygen, and argon were examined in this way.” 594 In every case the
kicks increased on the oscilloscope; the powerful beryllium radiation
knocked protons out of all the elements Chadwick tested.
It knocked about
the same number out of each element.
And, most important for his
conclusion, the energies of the recoiling protons were significantly greater
than they could possibly be if the beryllium radiation consisted of gamma
rays.
“In general,” Chadwick wrote, “the experimental results show that if the
recoil atoms are to be explained by collision with a [gamma-ray photon], we
must assume a larger and larger energy for the [photon] as the mass of the
struck atom increases.” 595 en, quietly, in what in fact is a devastating
criticism of the Joliot-Curie thesis, invoking the basic physical rule that no
more energy or momentum can come out of an event than went into it: “It is
evident that we must either relinquish the application of the conservation of
energy and momentum in these collisions or adopt another hypothesis
about the nature of the radiation.” When they read that sentence the Joliot-
Curies were deeply and properly chagrined.
e hypothesis Chadwick proposed adopting should come as no surprise:
“If we suppose that the radiation is not a [gamma] radiation, but consists of
particles of mass very nearly equal to that of the proton, all the difficulties
connected with the collisions disappear, both with regard to their frequency
and to the energy transfer to different masses.
In order to explain the great
penetrating power of the radiation we must further assume that the particle
has no net charge....
We may suppose it [to be] the ‘neutron’ discussed by
Rutherford in his Bakerian Lecture of 1920.”
Chadwick then worked the numbers to show that his hypothesis was the
correct one to explain the facts.
“It was a strenuous time,” he said aerward.
596 From beginning to end the work took ten days and he kept up his Cavendish responsibilities besides.
He
averaged perhaps three hours of sleep a night, labored over the weekend of
February 13–14 as well, finished probably on the seventeenth, a Wednesday,
the day he sent off a first brief report to Nature to establish priority of
discovery.
He titled that report, published as a letter to the editor, “Possible
existence of a neutron.” “But there was no doubt whatever in my mind or I
should not have written the letter.
”597
“To [Chadwick’s] great credit,” writes Segré in tribute, “when the neutron
was not present [in earlier experiments] he did not detect it, and when it
ultimately was there he perceived it immediately, clearly and
convincingly.598 ese are the marks of a great experimental physicist.”
A young Russian, Peter Kapitza, had come up to Cambridge in 1921 to
work at the Cavendish.
He was solid, dedicated, charming and technically
inventive and he soon made himself the apple of Rutherford’s eye, the only
one among all the boys, even including Chadwick, who could convince the
frugal director to allow large sums of money to be spent for apparatus.
In
1936 Rutherford would attack Chadwick angrily for encouraging the
construction of a cyclotron at the Cavendish; but already in 1932 Kapitza
had a separate laboratory in an elegant new brick building in the Cavendish
courtyard for his expensive experiments with powerful magnetic fields.
As
Kapitza had settled in at Cambridge he had noticed what he considered to
be an excessive and unproductive deference of British physics students to
their seniors.
He therefore founded a club, the Kapitza Club, devoted to
open and unhierarchical discussion.
Membership was limited and coveted.
Members met in college rooms and Kapitza frequently opened discussions
with deliberate howlers so that even the youngest would speak up to correct
him, loosening the grip of tradition on their necks.
at Wednesday Kapitza wined and dined the exhausted Chadwick into
what Mark Oliphant calls “a very mellow mood,” then brought him along to
a Kapitza Club meeting.599 “e intense excitement of all in the Cavendish,
including Rutherford,” Oliphant remembers, “was already remarkable, for
we had heard rumors of Chadwick’s results.” Oliphant says Chadwick spoke
lucidly and with conviction, not failing to mention the contributions of
Bothe, Becker, Webster and the Joliot-Curies, “a lesson to us all.” 600 C.
P.
Snow, who was also present, remembers the performance as “one of the
shortest accounts ever made about a major discovery.” When tall and
birdlike Chadwick finished speaking he looked over the assembly and
announced abruptly, “Now I want to be chloroformed and put to bed for a
fortnight.
”601
He deserved his rest.
He had discovered a new elementary particle, the
third basic constituent of matter.
It was this neutral mass that compounded
the weight of the elements without adding electrical charge.
Two protons
and 2 neutrons made a helium nucleus; 7 protons and 7 neutrons a nitrogen;
47 protons and 60 neutrons a silver; 56 protons and 81 neutrons a barium;
92 protons and 146 (or 143) neutrons a uranium.
And because the neutron was as massive as a proton but carried no
electrical charge, it was hardly affected by the shell of electrons around a
nucleus; nor did the electrical barrier of the nucleus itself block its way.
It
would therefore serve as a new nuclear probe of surpassing power of
penetration.
“A beam of thermal neutrons,” writes the American theoretical
physicist Philip Morrison, “moving at about the speed of sound, which
corresponds to a kinetic energy of only about a fortieth of an electron volt,
produces nuclear reactions in many materials much more easily than a beam
of protons of millions of volts energy, traveling thousands of times faster.
”602
Ernest Lawrence’s cyclotron, spiraling protons to million-volt energies for
the first time the same month that Chadwick made his fateful discovery,
fortunately proved to be adaptable to the production of neutrons.
More than
any other development, Chadwick’s neutron made practical the detailed
examination of the nucleus.
Hans Bethe once remarked that he considered
everything before 1932 “the prehistory of nuclear physics, and from 1932 on
the history of nuclear physics.
”603 e difference, he said, was the discovery
of the neutron.
Word of the discovery reached Copenhagen in the midst of preparations
for an amateur theatrical, a parody of Goethe’s Faust, to celebrate the tenth
anniversary of the opening of Bohr’s Institute for eoretical Physics.
e
postdoctoral dramatists gave the new particle the last word.
ey had cast
Wolfgang Pauli, a corpulent man with a smooth, round face and
protuberant, heavy-lidded eyes who resembled the actor Peter Lorre, as
Mephistopheles, Bohr as e Lord.
Eclectically they cast Chadwick in
absentia as Wagner and an anonymous illustrator drew him into the script,
“the personification of the ideal experimentalist” according to the stage
directions, balancing a vastly magnified neutron on his finger:604
In Copenhagen, as before in Cambridge, Chadwick reports his discovery
briefly and succinctly:
e Neutron has come to be.
Loaded with Mass is he.
605
Of Charge, forever free.
Pauli, do you agree?
Pauli steps forward to dispense his Mephistophelean blessing:
at which experiment has found—
ough theory has no part in—
Is always reckoned more than sound
To put your mind and heart in....
606
And a chorus of clowning, friendly physicists, Bohr’s brilliant young crew,
dances out to sing a finale and bring the curtain down:
Now a reality,
Once but a vision.607
What classicality,
Grace and precision!
Hailed with cordiality,
Honored in song,
Eternal Neutrality
Pulls us along!
It was the last peaceful time many of them would know for years to come.
7
Exodus
“Antisemitism is strong here and political reaction is violent,” Albert
Einstein wrote Paul Ehrenfest from Berlin in December 1919.
608 e letter
coincides with Einstein’s discovery by the popular press, the beginning of his
years of international celebrity.
“A new figure in world history,” the Berliner
Illustrirte Zeitung described him under a cover photograph on December 14,
“...
whose investigations signify a complete revision of our concepts of
nature, and are on a par with the insights of a Copernicus, a Kepler, a
Newton.
”609 Immediately the anti-Semites and fascists set to work on him.
Einstein was already, at forty-three, respected in the first rank of
theoretical physicists.
He had been nominated for the Nobel Prize in all but
two years since 1910, the secondings increasing in number aer 1917; Max
Planck, who was not given to exaggeration, wrote the Nobel Committee in
1919 that Einstein “made the first step beyond Newton.
”610, 611 e award might have come sooner than in 1922 (belatedly for 1921: the 1922 prize was
Bohr’s) had relativity been less paradoxical a revelation.
Physically Einstein was not yet the amused, grandfatherly notable of his
later American years.
His mustache was still dark and his thick black hair
had only begun to gray.
C.
P.
Snow would observe “a massive body, very
heavily muscled.
”612 e Swabian-born physicist’s friends thought his loud
laugh boyish; his enemies thought it rude.
“A powerful sensuality,” Snow
suspected, suspecting also that Einstein took his sensuality to be “one of the
chains of personality that ought to be slipped off.
”613 Nor had he yet learned,
in the psychoanalyst Erik Erikson’s words, “to look into cameras as if he
were meeting the eyes of the future beholders of his image.
”614 In the past
year Einstein had endured a stomach ulcer, jaundice and a painful divorce;
he had lost and partly regained fiy-six pounds; his mother was dying of
cancer: fatigue stained his expressive face.
Leopold Infeld, a young Polish
physicist who knocked at his door in postwar Berlin seeking a letter of
recommendation, found him “dressed in a morning coat and striped
trousers with one important button missing.” Infeld knew Einstein’s face
from magazines and newsreels.
“But no picture could reproduce the shining
glow of his eyes.
”615 ey were large and dark brown, and the diffident
young visitor was one of many—Leo Szilard was another—who found
comfort in those cold days in their honest warmth.
e immediate occasion for world notice was an eclipse of the sun.
Einstein had presented a paper to the Prussian Academy of Sciences in
Berlin on November 25, 1915, “e field equations of gravitation,” in which,
he reported happily, “finally the general theory of relativity is closed as a
logical structure.” 616 e paper stands as his first finished statement of the
general theory.
It was susceptible of proof.
It explained mysterious
anomalies in the orbit of Mercury—that confirmed prediction was the one
which le Einstein feeling something had snapped in him.
e general
theory also predicted that starlight would be deflected, when it passed a
massive body like the sun, through an angle equal to twice the value
Newtonian theory predicts.
e Great War delayed measurement of the
Einstein value.
A total eclipse of the sun (which would block the sun’s glare
and make the stars beyond it visible) due on May 29, 1919, offered the first
postwar occasion.
e British, not the Germans, followed through.
Cambridge astronomer Arthur Stanley Eddington led an expedition to
Principe Island, off the West African coast; the Greenwich Observatory sent
another expedition to Sobral, inland from the coast of northern Brazil.
A
joint meeting of the Royal Society and the Royal Astronomical Society at
Burlington House in London on November 6, under a portrait of Newton,
confirmed the stunning results: the Einstein value, not the Newton value,
held good.
“One of the greatest achievements in the history of human
thought,” J.
J.
omson told the assembled worthies.
“It is not the discovery
of an outlying island but of a whole continent of new scientific ideas.” 617
at was news.
e Times headlined it REVOLUTION IN SCIENCE and the
word spread.
From that day forward Einstein was a marked man.
It rankled German chauvinists, including rightist students and some
physicists, that the eyes of the world should turn to a Jew who had declared
himself a pacifist during the bloodiest of nationalistic wars and who spoke
out for internationalism now.
When Einstein prepared to offer a series of
popular lectures in the University of Berlin’s largest hall—everyone was
lecturing on relativity that winter—students complained of the expense for
coal and electricity.618 e student body president challenged Einstein to
hire his own hall.
He ignored the insult and spoke in the university hall as
scheduled, but at least one of his lectures, in February, was disrupted.
619
He was challenged more seriously the following August by an
organization assembled under obscure leadership and extravagant but
clandestine financing that called itself the Committee of German Scientists
for the Preservation of Pure Scholarship.
e 1905 Nobel laureate Philipp
Lenard, seeing relativity hailed and Einstein come to fame, retreated into a
vindictive anti-Semitism and lent his respectability to the Committee, which
attacked relativity theory as a Jewish corruption and Einstein as a tasteless
self-promoter.
e organization held a well-attended public meeting in
Berlin’s Philharmonic Hall on August 20.
Einstein went to listen—one
speaker, as Leopold Infeld recalled, “said that uproar about the theory of
relativity was hostile to the German spirit”—and stayed to scorn the
crackpot talk with laughter and satiric applause.620
e criticism nevertheless stung.
Einstein mistakenly thought the majority
of his German colleagues subscribed to it.621 Rashly he struck off an
uncharacteristically defensive statement.
It appeared in the Berliner Tageblatt
three days aer the Philharmonic Hall meeting.
“My Answer to the
Antirelativity eory Company Ltd.” 622 shocked his friends, but it
presciently identified the deeper issues of the Committee attack.
“I have
good reason to believe that motives other than a desire to search for truth
are at the bottom of their enterprise,” Einstein wrote.
And parenthetically,
leaving his implications unstated in elision: “(Were I a German national,
with or without swastika, instead of a Jew of liberal, international
disposition, then...).” A month later his sense of humor had returned; he
asked Max Born not to be too hard on him: “Everyone has to sacrifice at the
altar of stupidity from time to time...
and this I have done with my
article.
”623 But before then he had seriously considered leaving Germany.
It would not be the first time.
Einstein had renounced German citizenship
and departed the country once before, at the extraordinary age of sixteen.
at earlier rejection, which he reversed two decades later, prepared him for
the final one, aer the Weimar interlude, when Adolf Hitler came to power.
Germany had been united in empire for only eight years when Einstein
was born in Ulm on March 14, 1879.
He grew up in Munich.
He was slow to
speak, but he was not, as legend has it, slow in his studies; he consistently
earned the highest or next-highest marks in mathematics and Latin in
school and Gymnasium.
At four or five the “miracle” of a compass his father
showed him excited him so much, he remembered, that he “trembled and
grew cold.” It seemed to him then that “there had to be something behind
objects that lay deeply hidden.” 624 He would look for the something which
objects hid, though his particular genius was to discover that there was
nothing behind them to hide; that objects, as matter and as energy, were all;
that even space and time were not the invisible matrices of the material
world but its attributes.
“If you will not take the answer too seriously,” he
told a clamorous crowd of reporters in New York in 1921 who asked him for
a short explanation of relativity, “and consider it only as a kind of joke, then
I can explain it as follows.
It was formerly believed that if all material things
disappeared out of the universe, time and space would be le.
According to
the relativity theory, however, time and space disappear together with the
things.
”625
e quiet child became a rebellious adolescent.
He was working his own
way through Kant and Darwin and mathematics while the Gymnasium
pounded him with rote.
He veered off into religion—Judaism—and came
back bitterly disillusioned: “rough the reading of popular scientific books
I soon reached the conviction that much of the stories in the Bible could not
be true....
e consequence was a positively fanatic free-thinking coupled
with the impression that youth is intentionally being deceived by the state
through lies; it was a crushing impression.
Suspicion against every kind of
authority grew out of this experience, a sceptical attitude towards the
convictions which were alive in any specific social environment.” 626
His father stumbled in business, not for the first time.
627 e family
moved across the Alps to Milan to start again, but Albert stayed behind in a
boardinghouse to complete his Gymnasium work.
He was probably expelled
from the Gymnasium before he could quit.
He acquired a doctor’s certificate
claiming nervous disorders.
It was not only the autocracy of his German
school that he despised.
“Politically,” he wrote later, “I hated Germany from
my youth.” 628 He had thought of renouncing his citizenship while his family
was still in Munich, as a rebellious adolescent of fieen.
at began a long
family debate.
He won it aer he moved from Milan to Zurich to try again to
finish his schooling; his father wrote the German authorities on his behalf.
Einstein renounced his German citizenship officially on January 28, 1896.
e Swiss took him aboard in 1901.
He liked their doughty democracy and
was prepared to serve in their militia but was found medically unfit (because
of flat feet and varicose veins); but one reason he quit Germany was to avoid
the duty of Prussian conscription, Kadavergehorsamkeit, the obedience of
the corpse.629
e boy and the young man rebelled to protect the child within—the
“victorious child,” Erik Erikson has it in Einstein’s case, the child with its
uninhibited creativity preserved into adulthood.630 Einstein grazes the point
in a letter to James Franck:
I sometimes ask myself how it came about that I was the one to develop
the theory of relativity.
e reason, I think, is that a normal adult never
stops to think about problems of space and time.
ese are things which
he has thought of as a child.
But my intellectual development was
retarded, as a result of which I began to wonder about space and time
only when I had already grown up.631
“Relativity” was a misnomer.
Einstein worked his way to a new physics by
demanding consistency and greater objectivity of the old.
If the speed of
light is a constant, then something else must serve as the elastic between two
systems at motion in relation to one another—even if that something else is
time.
If a body gives off an amount E of energy its mass minutely
diminishes.
But if energy has mass, then mass must have energy: the two
must be equivalent: E = mc2, E/c2 = m.632 (I.e., an amount of energy E in joules is equal to an amount of mass m in kilograms multiplied by the
square of the speed of light, an enormous number, 3 × 108 meters per
second times 3 × 108 m/s = 9 × 1016 or 90,000,000,000,000,000 joules per
kilogram.
Dividing E by c2 demonstrates how large an amount of energy is
contained within even a small mass.)
Einstein came to that beautiful, harrowing equivalency in 1907, in a long
paper published in the Jahrbuch der Radioaktivität und Elektronik.
“It is
possible,” he wrote there, “that radioactive processes may become known in
which a considerably larger percentage of the mass of the initial atom is
converted into radiations of various kinds than is the case for radium.
”633
Like Soddy and Rutherford earlier in England, he saw the lesson of radium
that there was vast energy stored in matter, though he was not at all sure that
it could be released, even experimentally.
“e line of thought is amusing
and fascinating,” he confided to a friend at the time, “but I wonder if the
dear Lord laughs about it and has led me around by the nose.” 634 He had his
Ph.D.
then from the University of Zurich and Max Planck had begun to
correspond with him, but he had not yet le the patent office where he
worked as a technical expert from 1902 to 1909, the years of his first great
burst of papers including those on Brownian motion, the photoelectric effect
and special relativity.
He habilitated as a Privatdozent at the University of Bern in 1908 but held
on to the patent-office job for another year for security.
Finally in October
1909, aer receiving his first honorary doctorate, he moved up to associate
professor at the University of Zurich.
A full professorship enticed him to
isolated Prague—he was married now, with a wife and two sons to support
—but happily the Polytechnic in Zurich drew him back a year later with a
matching offer.
e academic hesitations measure how radically new was his
work.
It was 1913 before Max Planck, Fritz Haber and a muster of German
notables, recognizing the waste, offered him a triple appointment in Berlin: a
research position under the aegis of the Prussian Academy of Sciences, a
research professorship at the university and the directorship of the planned
Kaiser Wilhelm Institute for Physics.
Aer the Germans le, Einstein
quipped to his assistant, Otto Stern, that they were “like men looking for a
rare postage stamp.” 635
He arrived in Berlin in April 1914.
In the war years, separated from his
first wife and living alone, he completed the general theory.
To Max Born
that “great work of art” was “the greatest feat of human thinking about
nature, the most amazing combination of philosophical penetration,
physical intuition, and mathematical skill” even though “its connections
with experience were slender.” 636 Einstein’s crowning achievement
ameliorated for him the universal madness of the war:
I begin to feel comfortable amid the present insane tumult, in conscious
detachment from all things which preoccupy the crazy community.
Why
should one not be able to live contentedly as a member of the service
personnel in the lunatic asylum?
Aer all, one respects the lunatics as the
people for whom the building in which one lives exists.
Up to a point, you
can make your own choice of institution—though the distinction between
them is smaller than you think in your younger years.637
Einstein raised funds for the Zionist cause of a Hebrew university in
Palestine on a first trip to the United States, with Chaim Weizmann, in April
and May 1921.
He had seen the crowds of Eastern Jews stumbling into
Berlin in the wake of war and revolution, watched the German incitement
against them and decided to take their part.
His guide to Zionist thinking
was the eloquent spokesman and organizer Kurt Blumenfeld, who also
served in that capacity to the young Hannah Arendt.
It was Blumenfeld who
convinced him to accompany Weizmann to America—his relations with the
forceful, single minded Weizmann, Einstein told Abraham Pais once, “were,
as Freud would say, ambivalent.
”638 He lectured on relativity at Columbia,
the City College of New York and Princeton, met Fiorello La Guardia and
President Warren G.
Harding, conceived “a new theory of eternity” sitting
through formal speeches at the annual dinner of the National Academy of
Sciences and spoke to crowds of enthusiastic American Jews.639
Back home he wrote that he “first discovered the Jewish people” in
America.
“I have seen any number of Jews, but the Jewish people I have
never met either in Berlin or elsewhere in Germany.
is Jewish people
which I found in America came from Russia, Poland, and Eastern Europe
generally.
ese men and women still retain a healthy national feeling; it has
not yet been destroyed by the process of atomization and dispersion.
”640 e
statement implicitly criticizes the Jews of Germany, whose “undignified
assimilationist cravings and strivings,” Einstein wrote elsewhere, had
“always...
annoyed” him.641 Blumenfeld propounded a radical, post-
assimilatory Zionism and had taught him well.
A decade later Hannah
Arendt would write that “in a society on the whole hostile to Jews...
it is
possible to assimilate only by assimilating to anti-Semitism also.” 642 Einstein
specialized in driving assumptions to their logical conclusions: clearly he
had arrived at a similar understanding of the “Jewish question.”
He was now not only the most famous scientist in the world but also a
known spokesman for Jewish causes.
In Berlin on June 24, 1922, right-wing
extremists gunned down Walther Rathenau, the Weimar Republic’s first
Foreign Minister, a physical chemist and industrialist friend of Einstein and
a highly visible Jew.
It appeared that Einstein might be next.
“I am supposed
to belong to that group of persons whom the people are planning to
assassinate,” he wrote Max Planck.
“I have been informed independently by
serious persons that it would be dangerous for me in the near future to stay
in Berlin or, for that matter, to appear anywhere in public in Germany.” 643
He lived privately until October, then le with his second wife, Elsa, on a
long trip to the Far East and Japan, receiving notice of his Nobel Prize en
route.
He spent twelve days in Palestine on the way back and stopped over in
Spain.
By the time he returned to Berlin, German preoccupation with
politics had temporarily retreated behind preoccupation with the Dadaistic
mark, then soaring toward 54,000 to the dollar.644 Einstein went on with his
work, including the Einstein-Szilard refrigerator pump and his first efforts
toward a unified field theory, but began frequently to travel abroad.
* * *
e anti-Semitism Einstein found strong in Berlin in December 1919 was
rampant in Munich.
Pale, thin, thirty-year-old Adolf Hitler sat down that
month at the single battered table in the cramped office of the German
Workers Party, formerly a taproom, to dra his party’s platform.
A grotesque
wood carving served as inspiration.
It would follow its master into history; a
touring Australian academic encountered it again in 1936:
I was being shown round a famous collection of [Nazi] Party relics in
Munich.
e curator was a mild old man, a student of the old German
academic class.645 Aer showing me everything, he led, almost with bated
breath, to his pièce de résistance.
He produced a small sculptured wooden
gibbet from which was suspended a brutally realistic figure of a dangling
Jew.
is piece of humourless sadism, he said, decorated the table at
which Hitler founded the Party, seventeen years ago.
His pale blue eyes shining, Hitler read out the twenty-five points of his
party’s program the following February in the Festsaal of Munich’s
Horäuhaus before nearly two thousand people, the largest crowd the little
German Workers Party had yet attracted.
“ese points of ours,” he had
shouted in triumph the day he finished draing them, “are going to rival
Luther’s placard on the doors of Wittenberg!” All or part of six of them
applied specifically to Jews: that Jews were not countrymen “of German
blood” and therefore could not be citizens; that only citizens could hold
public office or publish German-language newspapers; that no more
nonGermans might immigrate into the country and that all non-Germans
admitted since the beginning of the Great War should be expelled.
646 e
twenty-five points were never officially declared the program of the
Nationalsozialistiche Deutsche Arbeiterpartei, the Nazi Party, which the
German Workers Party evolved to, but their power was felt nevertheless.
e Beer Hall Putsch on November 8, 1923, delivered Hitler to a
comfortable, sunlit cell in Landsberg prison, where he dictated his personal
and political testament to his bashful acolyte Rudolf Hess.
Mein Kampf has
much to say about the Jews.
Across the nearly seven hundred pages of its
two volumes it refers to Jewry more frequently than to any other subject
except Marxism—and Hitler considered Marxism a Jewish invention and a
Jewish “weapon.” 647
Jews, the future Chancellor of Germany declares in Mein Kampf, are “no
lovers of water.
”648 He “oen grew sick to my stomach from [their] smell.”
eir dress is “unclean,” their appearance “generally unheroic.” “A foreign
people,” they have “definite racial characteristics”; they are “inferior
being[s],” “vampires” with “poison fangs,” “yellow fist[s]” and “repulsive
traits.” “e personification of the devil as the symbol of all evil assumes the
living shape of the Jew.”
e attributes of the Jew are legion, Hitler goes on.
e Jew is “a garbage
separator, splashing his filth in the face of humanity.” Or he is a “scribbler...
who poison[s] men’s souls like germ-carriers of the worst sort.” Or “the cold-
hearted, shameless, and calculating director of this revolting vice traffic in
the scum of the big city.” “Was there any form of filth or profligacy,” Hitler
asks rhetorically, “...
without at least one Jew involved in it?
If you cut even
cautiously into such an abscess, you found, like a maggot in a rotting body,
oen dazzled by the sudden light—a kike!”
e Jew is “no German.” Jews are a “race of dialectical liars”; a “people
which lives only for this earth”; “the great masters of the lie”; “traitors,
profiteers, usurers, and swindlers”; a “world hydra”; “a horde of rats.” “Alone
in this world they would stifle in filth and offal.”
“Without any true culture,” the Jew is “a parasite in the body of other
peoples,” “a sponger who like a noxious bacillus keeps spreading as soon as a
favorable medium invites him.” “He lacks idealism in any form.” He is an
“eternal blood-sucker” of “diabolical purposes,” “restrained by no moral
scruples,” who “poisons the blood of others, but preserves his own.” He
“systematically ruins women and girls”: “With satanic joy on his face, the
black-haired Jewish youth lurks in wait for the unsuspecting girl whom he
defiles with his blood, thus stealing her from her people.” He is “master over
bastards and bastards alone” and “it was and is Jews who bring the Negroes
into the Rhineland, always with the same secret thought and clear aim of
ruining the hated white race by the necessarily resulting bastardization.”
Syphilis is a “Jewish disease,” a “Jewification of our spiritual life and
mammonization of our mating instinct [that] will sooner or later destroy
our entire offspring.” e Jew “makes a mockery of natural feelings,
overthrows all concepts of beauty and sublimity, of the noble and the good,
and instead drags men down into the sphere of his own base nature.” “An
apparition in a black caan and black hair locks,” responsible for “spiritual
pestilence worse than the Black Death of olden times,” the Jew is a “coward,”
a “plunderer,” a “menace,” a “foreign element,” a “viper,” a “tyrant,” a
“ferment of decomposition.”
e sun shines in the wide windows of Hitler’s cell at Landsberg.649
Boyish in lederhosen, he remembers that he was blinded by mustard gas
below Ypres.
650 He wrote a poem during the war, a poem out of a dream,
before he took shrapnel in the thigh on the Somme, before Ypres:
I oen go on bitter nights651
To Wotan’s oak in the quiet glade
With dark powers to weave a union—
e runic letters the moon makes with its magic spell
And all who are full of impudence during the day
Are made small by the magic formula!.....
Hitler’s testament is almost finished.
He dictates, his blanched face
tumefying:
If at the beginning of the War and during the War twelve or fieen
thousand of these Hebrew corrupters of the people had been held under
poison gas, as happened to hundreds of thousands of our very best
German workers in the field, the sacrifice of millions at the front would
not have been in vain.652
* * *
e dispersion of the Jewish people from Palestine—the Diaspora—began in
the sixth century B.C.
when Babylon conquered the southern Palestinian
kingdom of Judah, destroyed Solomon’s temple and carried a large body of
Jews into captivity.
653 By the beginning of the Christian era, under Roman
hegemony, Jews had established communities in Egypt, in Greece, around
the Mediterranean and on the shores of the Black Sea and there were Jewish
slaves with the Roman legions on the Rhine.
Conditions worsened again for
the Jews when the Empire was Christianized in the fourth century A.D.
with
the conversion of the Emperor Constantine; Christianity and Judaism
competed, in a Darwinian sense, for the same Holy Land and the same holy
books.
Under systematic persecution only a small remnant of the Jewish
people remained in Judea.
e fantasy of Jews as a brotherhood of evil was
invented during this era when Christianity fought its missionary way to
dominance.
654
In the disorder of the Dark Ages the Jews lost even their vestigial Roman
citizenship.
ose who sought protection won it from rulers like
Charlemagne’s son Louis the Pious who knew their worth as merchants and
crasmen, but the price of protection was that they became the ruler’s
property.
eir rights were thus no longer inherent but chartered.
Against
that threatening insecurity Jews could count their gain of judicial autonomy:
within their communities they were allowed to administer their own laws.
In
parts of Spain they had the power even of life and death.
e medieval Church, challenged by the spread of learning and the
militancy of Islam to shore up its defenses against heresy, exercised its
increasing power over the Jews balefully.
e Lateran Councils of 1179 and
1215 made the baleful conflict visible by denying Jews authority over
Christians, denying them Christian servants, relegating moneylending to
Jews by forbidding it to Christians, forbidding Christians lodging in Jewish
quarters and thus officially sanctioning the establishment of ghettos and,
most onerously, requiring every Jew to wear a distinguishing badge—
frequently, on local authority, the yellow Magen David that the Nazis later
restored.
Every Jew who ventured from the ghetto distinctively marked was
a painted bird, exposed to attack.
e fantasy of Jews as a brotherhood of evil swelled in medieval times to a
full-blown demonology.
e Jewish Messiah became the Antichrist.
e
Jews became sorcerers of Satan who poisoned wells, tortured the
consecrated Host and murdered Christian children to collect their blood for
diabolic rites.
When the Black Death struck in the fourteenth century, a
supposedly demonic people who poisoned wells were obvious suspects: they
needed only to have infiltrated some more vicious poison into the water
supply.
A quarter of Europe died of plague, and in that time of horror tens of
thousands of Jews were burned, drowned, hanged or buried alive in
retaliation.
Massacre became endemic; 350 Jewish communities were
decimated in German lands alone.
e English were the first to expel the Jews entirely.
e Jews of England
belonged to the Crown, which had systematically extracted their wealth
through a special Exchequer to the Jews.
By 1290 it had bled them dry.
Edward I thereupon confiscated what little they had le and threw them out.
ey crossed to France, but expulsion from that country followed in 1392;
from Spain, at the demand of the Inquisition, in 1492; from Portugal in
1497.
Since Germany was a region of multiple sovereignties, German Jews
could not be generally expelled.
ey had been fleeing eastward from bitter
German persecution in any case since the twelh century.
e Jews expelled from Western Europe fled to Poland, a large and thinly
populated kingdom where elected monarchs welcomed them with generous
charters.
e medieval German of these emigrant Ashkenazim evolved to
Yiddish; they founded villages and towns; they dispersed up and down the
long eastern Polish frontier and lived in relative peace for two hundred
years.
Twenty-five thousand at the end of the fieenth century had increased at
least tenfold by the middle of the seventeenth.
en, in violent wars with
Russia and Sweden, Poland began to break up.
Cossacks and their peasant
allies murdered great numbers of Jews and sacked hundreds of their
communities.
e Ukraine was split in two; Poland lost the northern half to
Russia.
War and disorder continued into the eighteenth century with
Prussia, Austria and Turkey variously joining battle.
When Russia invaded
Poland in 1768, Prussia proposed a three-way partition with Austria to
forestall a complete takeover.
at led to Poland’s partial dismemberment in
1772.
In 1795, aer another Russian invasion, the country was completely
partitioned and ceased to exist.
(Much truncated, it was revived by the
Congress of Vienna in 1814 as Congress Poland, joined to Russia by the
linkage of Polish kingship for the Czar.) Its Jewish population had increased
by then to more than one million souls.
Prussia acquired about 150,000 but
promptly expelled them eastward.
Austria acquired about 250,000.
Russia,
which soon controlled more than three-fourths of what had been the Polish
commonwealth, then also controlled the fates of most of the Eastern Jews.
But while Poland had welcomed them, Russia despised them.
Its economy
was too primitive to need their commercial skills and it abhorred their
religion.
To Catherine the Great her one million new subjects were first and
foremost “the enemies of Christ.” 655
e enemies of Christ became Russia’s “Jewish problem.” In Russia’s
benighted intolerance it framed only two solutions: assimilation (by
conversion to Christianity) or expulsion.
For the interim it practiced
quarantine.
A decree of 1791 limited Jewish residence to the formerly Polish
territories and the unpopulated steppes above the Black Sea, a region that
extended north across 286,000 square miles of central Europe to the Baltic:
the Pale of Settlement (“pale” in its old sense of “enclosed by a boundary”).
e Ashkenazim numbered one-ninth of the Pale’s total population, and
might have prospered there, but they were burdened with further
restrictions.
ey were heavily taxed, they could not live in the villages as
they had done for generations, they could not keep the village inns or sell
liquor to the peasants.
eir traditional local governments, the kehillot, were
stripped of legal authority but required to collect Jewish taxes.
More
horribly, under Nicholas I aer 1825 the kehillot were charged to conscript
twelve-year-old Jewish children for a lifetime of forced service in the Russian
Army—six years of brutal “education” followed by twenty-five years in the
ranks—a fate that befell between 40,000 and 50,000 Jewish sons before the
requirement was relaxed in 1856.
e memory of that cruelty would endure:
Edward Teller’s grandmother responded to his childhood misbehavior, he
reminisced once with a friend, by warning him to be a good boy or the
Russians would get him.656
While Eastern Jews toiled to survive in Mother Russia, emancipation was
proceeding in the West.
Small Jewish communities had reestablished
themselves, made up partly of nominal converts to Christianity who had
escaped Spain and Portugal for Holland and England and America, partly of
Eastern returnees.
e Austrian emperor Joseph II issued an Edict of
Tolerance in 1782.
e edicts of emperors were less important to the political future of the
Jewish people than the temper of the Enlightenment with its religious
skepticism and its faith in the self-evident rights of man.
e time had come
in the evolution of European forms of government when no single group or
class any longer had the power to dominate all others as the nobility had
previously done.
e nation-state evolved in part to remove this impasse by
investing power in the state itself.
Such a mechanism made no distinction
between Jew and Christian.
American Jews thus became American citizens
automatically with the Revolution and the Bill of Rights.
e French, remembering ghettos and expulsions, found the
emancipation of the Jews of France more difficult.
“e Jews should be
denied everything as a nation,” the Count of Clermont-Tonnerre argued in
the French National Assembly, “but granted everything as individuals....
It
is intolerable that [they] should become a separate political formation or
class in the country.
Every one of them must individually become a
citizen.
”657 When a Jewish community contracted its loyalty to a monarch in
exchange for his protection it only did what other medieval classes and
orders had done.
But the nation-state was secular and it considered the
autonomous Jewish theocracies lodged within its borders in secular terms.
In secular terms a separate political body, theocratic or not, to which
citizens gave their first loyalty was potentially a rival and inherently
subversive.
Much monstrosity would devolve from that reification.
In the
meantime Liberty, Equality and Fraternity prevailed and the Jews of France
became citoyens on a September Tuesday in 1791.
Emancipations as they progressed within less revolutionary states
included Holland-Belgium, 1795; Sweden, 1848; Denmark and Greece,
1849; England by a gradual unmuddling completely in 1866; Austria, 1867;
Spain by the withdrawal of its 1492 order of expulsion in 1868; the new
German Empire, 1871.
ough they were influential out of all proportion to
their numbers, the emancipated Jews of Western Europe, many of whom
moved directly to assimilate, were only a minute fraction of the Diaspora.
e preponderance of the Jewish people, increased by 1850 to 2.5 million, by
1900 to 5 million, struggled in increasing misery in the Pale.
At his coronation in 1856, amid remissions and amnesties, Czar
Alexander II abolished the special conscription of Jewish children.
Other
alleviations followed, all designed to encourage Jewish assimilation.
“Useful”
Jews—wealthy merchants, university graduates, crasmen and medical
assistants—were allowed residence in the interior of Russia, beyond the Pale.
e universities were restored to autonomy and Jews allowed to attend.
Within the Pale Jews received limited civil rights and became eligible for
local councils.
But the Czar who freed 30 million peasants from serfdom
was dismayed to discover that reform aer so many centuries of repression
might lead not to expressions of gratitude but to revolutionary agitation and
revolt, as it did in Congress Poland in 1863, and the liberalization of Russian
life stalled.
Revolutionaries—a splinter group that called itself “e People’s Will”—
murdered Alexander on March 13, 1881, by lobbing a hail of small bombs
into his open carriage in broad daylight on a main street of St.
Petersburg as
he drove home from reviewing the Imperial Guards.
One member of e
People’s Will, not a bomber, was Jewish; that was pretext enough, in the
confused aermath of regicide, to blame the assassination on the Jews.
A
wave of pogroms—the curious Russian word refers to a violent riot by one
group against another—began that continued until 1884.
“Jewish disorders,”
the dogmatic new Czar, Alexander III, called these murderous raids of
drunken mobs on Jewish quarters everywhere in the Pale.658 ey erupted
with the active participation or tacit consent of the authorities.
More than
two hundred Jewish communities were attacked.
e first wave of pogroms
—there would be more in later decades—le 20,000 Jews homeless and
100,000 ruined.
659 Women were raped, families murdered.
e government
blamed the violence on anarchists and moved to expel even the “useful” Jews
back into the ghettos of the Pale.
With the pogroms came the 1882 May Laws, revising or repealing
previous reforms and imposing catastrophic new restrictions.
Between 1881
and 1900 more than 1 million Jews emigrated from Russia and central
Europe to the United States and another 1.5 million between 1900 and 1920.
A much smaller number of emigrants, like Chaim Weizmann, chose
Western Europe and England.
Most found less opportunity there than their
American counterparts and more virulent anti-Semitism.
One of the important sources of German anti-Semitism in the years aer
the Great War was the strange forgery known as e Protocols of the Elders of
Zion.
Adolf Hitler took the Protocols as a text, to the extent that National
Socialism had a text, for world domination.
“I have read e Protocols of the
Elders of Zion” Hitler told one of his loyalists; “it simply appalled me.
e
stealthiness of the enemy, and his ubiquity!
I saw at once that we must copy
it—in our own way, of course.
”660 Heinrich Himmler confirmed that
connection: “We owe the art of government to the Jews.” To the Protocols, he
meant, which “the Führer learned by heart.
”661
e Protocols were Russian work.
ey link the Jewish experience in
Russia with the Jewish experience in Germany, where so few Jews actually
lived—only about 500,000 in 1933, less than 1 percent of the German
population.
If Russia’s hostility to the Jews was rooted in part in religious
conflict, German anti-Semitism, by contrast, needed a secular myth.
A half-
educated apostate autodidact like Hitler especially needed some structure on
which to hang his anti-Semitic pathology.
German anti-Semitism had
plentiful German antecedents—Richard Wagner’s foamings were high on
Hitler’s list—but the Protocols happened to arrive at the right time and place
to earn a prominent position well forward.
In the 1920s and 1930s millions
of copies of various translations and editions were sold throughout the
world.
e book is cast in the form of lectures and begins in midsentence, its
scene unset, as if torn from the evil hands of its perpetrators.
To supply the
missing background, editors usually bound in explanatory material.
A
popular preliminary was a chapter from the novel Biarritz, the work of a
minor German postal official, entitled “In the Jewish Cemetery in Prague.”
Editors offered this lurid fiction, like the fiction of the Protocols themselves,
as fact.
e historian Norman Cohn summarizes its setting:
At eleven o’clock the gates of the cemetery creak soly and the rustling of
long coats is heard, as they touch against the stones and shrubbery.
A
vague white figure passes like a shadow through the cemetery until it
reaches a certain tombstone; here it kneels down, touches the tombstone
three times with its forehead and whispers a prayer.662 Another figure
approaches; it is that of an old man, bent and limping; he coughs and
sighs as he moves.
e figure takes its place next to its predecessor and it
too kneels down and whispers a prayer....
irteen times this procedure
is repeated.
When the thirteenth and last figure has taken its place a clock
strikes midnight.
From the grave there comes a sharp, metallic sound.
A
blue flame appears and lights up the thirteen kneeling figures.
A hollow
voice [the thirteenth figure] says, “I greet you, heads of the twelve tribes of
Israel.” It is the Devil speaking; and the figures dutifully reply, “We greet
you, son of the accursed.”
e Protocols follow.
ey are twenty-four in all—some eighty pages in book
form.
“What I am about to set forth, then,” explains the speaker at the
beginning of the first Protocol, “is our system from the two points of view,
that of ourselves and that of the goyim” Much about the system set forth is
incoherent, but the Protocols elaborate three main themes: a bitter attack on
liberalism, the political methods of the Jewish world conspiracy and an
outline of the world government the Elders expect soon to install.663
e attack on liberalism would be comical if the Protocols had not found
such vicious use.
Liberalism “produced Constitutional States...
and a
constitution, as you well know, is nothing else but a school of discords,
misunderstandings, quarrels, disagreements, fruitless party agitations, party
whims....
We replaced the ruler by a caricature of a government—by a
president, taken from the mob, from the midst of our puppet creatures, our
slaves.” 664 A touching loyalty to the Russian ancien régime surfaces from time to time and must have given European readers pause:
e principal guarantee of stability of rule is to confirm the aureole of
power, and this aureole is attained only by such a majestic inflexibility of
might as shall carry on its face the emblems of inviolability from mystical
causes—from the choice of God.
Such was, until recent times, the Russian
autocracy, the one and only serious foe we had in the world, without
counting the Papacy.665
In brief, the Elders have stage-managed the invention and dissemination
of modern ideas—of the modern world.
Everything more recent than the
Russian imperial system of czar, landed nobility and serfs is part and parcel
of their diabolical work.
Which helps explain how so obscure a study as
physics came in Germany in the 1920s to be counted part of the Jewish
conspiracy.
e Elders work to establish a world autocracy ruled by a leader who is a
“patriarchial paternal” guardian.
Liberalism will be rooted out, the masses
led away from politics, censorship strict, freedom of the press abolished.
A
third of the population will be recruited for amateur spying (“It will then be
no disgrace to be a spy and informer, but a merit”) and a vast secret police
will keep order.666 All these were Nazi strategies, and certainly Hitler’s debt
to the Protocols is evident in Mein Kampf and explicitly acknowledged.
667
Russia’s contribution to German anti-Semitism was plagiarized from a
work of political satire, Dialogues from Hell Between Montesquieu and
Machiavelli, written by a French lawyer, Maurice Joly, and first published in
Brussels in 1864.
Montesquieu speaks for liberalism, Machiavelli for
despotism.
e concoction of the Protocols was probably the work of the
head of the czarist secret police outside Russia, a Paris-based agent named
Pyotr Ivanovich Rachkovsky.
Borrowing and paraphrasing Machiavelli’s
speeches without even bothering to change their order and attributing them
to a secret Jewish council, Rachkovsky was attempting to discredit Russian
liberalism by showing it to be a Jewish plot.
A St.
Petersburg newspaper
serialized the earliest version of the Protocols in 1903.
It was one of three
books belonging to the Czarina Alexandra Feodorovna—the other two were
the Bible and War and Peace—found among her possessions at Ekaterinburg
aer the murder of the imperial family by Communist revolutionaries on
July 17, 1918.
at coincidence returned the Protocols west.
Fyodor Vinberg, who
arranged the German translation and publication of the Protocols in Berlin
in 1920, was a colonel in the Imperial Guard.
e Czarina had been an
honorary colonel of his regiment and he had worshiped her.
He escaped to
Germany at the end of the Great War convinced that her murderers had
been Jews.
ereaer revenge on the Jews was the central fixation of his life.
He was a friend to Hitler’s advisers, particularly the Nazi Party
“philosopher,” Russian-born Alfred Rosenberg, who published a study of the
Protocols in 1923.
e fiction of a Jewish world conspiracy had practical value for the Nazi
Party.
As it had done for earlier anti-Semitic parties, writes Hannah Arendt,
who was on the scene as a student in Berlin in the 1920s, it “gave them the
advantage of a domestic program, and conditions were such that one had to
enter the arena of social struggle in order to win political power.
ey could
pretend to fight the Jews exactly as the workers were fighting the
bourgeoisie.
eir advantage was that by attacking the Jews, who were
believed to be the secret power behind governments, they could openly
attack the state itself.
”668
e fiction also served for propaganda, to reassure the German people: if
the Jews could dominate the world, then so could the Aryans.
Arendt
continues: “us the Protocols presented world conquest as a practical
possibility, implied that the whole affair was only a question of inspired or
shrewd know-how, and that nobody stood in the way of a German victory
over the entire world but a patently small people, the Jews, who ruled it
without possessing instruments of violence—an easy opponent, therefore,
once their secret was discovered and their method emulated on a larger
scale.” 669
But the scurrilities of Mein Kampf, which on the evidence of their
incoherence are not calculated manipulations but violent emotional
outbursts, demonstrate that Hitler pathologically feared and hated the Jews.
In black megalomania he masked an intelligent, industrious and much-
persecuted people with the distorted features of his own terror.
And that
would make all the difference.
* * *
A German journalist had the temerity in 1931 to ask Adolf Hitler where he
would find the brains to run the country if he took it over.
Hitler snapped
that he would be the brains but went on contemptuously to enlist the help of
the German class that still resisted voting the Nazis into power:
Do you think perhaps that, in the event of a successful revolution along
the lines of my party, we would not inherit the brains in droves?
Do you
believe that the German middle class, this flower of the intelligentsia,
would refuse to serve us and place their minds at our disposal?
e
German middle class would take its stand on the famed ground of the
accomplished fact; we will do what we like with the middle class.
670
But what about the Jews, the journalist persisted—those talented people, war
heroes among them, Einstein among them?
“Everything they have created
has been stolen from us,” Hitler charged.
“Everything that they know will be
used against us.
ey should just go and foment their unrest among other
peoples.
We do not need them.”
At noon on January 30, 1933, Adolf Hitler, forty-three years old, gleefully
accepted appointment as Chancellor of Germany.
With the Reichstag fire
and the subsequent suspension of constitutional liberties, with the Enabling
Act of March 23 by which the Reichstag voluntarily gave over its powers to
the Hitler cabinet, the Nazis began to consolidate their control.
ey moved
immediately to legalize anti-Semitism and abolish the civil rights of German
Jews.
Meeting at his country retreat in Berchtesgaden with Joseph Goebbels,
now his propaganda minister, Hitler decided on a boycott of Jewish
businesses as an opening sally.
671 e national boycott began on Saturday,
April 1.
Already during the previous week Jewish judges and lawyers had
been dismissed from practice in Prussia and Bavaria.
Now newspapers
conveniently published business addresses and teams of Nazi storm troopers
stationed themselves at storefronts to direct the mobs.
Jews caught in the
streets were beaten while the police looked on.
e boycott was a nationwide
German pogrom and it lasted through a violent weekend.
A month earlier, the evening aer the Reichstag fire, Wolfgang Pauli had
dropped in on a Göttingen group that included Edward Teller.
e group
had discussed Germany’s political situation and Pauli had declared
emphatically that the idea of a German dictatorship was Quatsch, Pauli’s
favorite dismissal: rubbish, mush, nonsense.
“I have seen dictatorship in
Russia,” he told them.
“In Germany it just couldn’t happen.
”672 In Hamburg
Otto Frisch had mustered similar optimism, as indeed had many Germans.
“I didn’t take Hitler at all seriously at first,” Frisch told an interviewer later.
“I
had the feeling, ‘Well, chancellors come and chancellors go, and he will be
no worse than the rest of them.’ en things began to change.” 673 e ird
Reich promulgated its first anti-Jewish ordinance on April 7.
e Law for the
Restoration of the Professional Civil Service, the harbinger of some four
hundred anti-Semitic laws and decrees the Nazis would issue, changed
Teller’s life, Pauli’s, Frisch’s, the lives of their colleagues decisively, forever.
It
announced bluntly that “civil servants of non-Aryan descent must retire.
”674
A decree defining “non-Aryan” followed on April 11: anyone “descended
from non-Aryan, especially Jewish, parents or grandparents.
”675 Universities
were state institutions.
Members of their faculties were therefore civil
servants.
e new law abruptly stripped a quarter of the physicists of
Germany, including eleven who had earned or would earn Nobel Prizes, of
their positions and their livelihood.
676 It immediately affected some 1,600
scholars in all.677 Nor were academics dismissed by the Reich likely to find
other work.
To survive they would have to emigrate.
Some had already le, among them Einstein and the older Hungarians.
Einstein read the signs correctly because he was Einstein and because he had
borne the brunt of the attack since immediately aer the war; the
Hungarians had become connoisseurs by now of advancing fascism.
eodor von Kármán departed first, from Aachen.
He had pioneered
aeronautical physics; the California Institute of Technology, then vigorously
assembling its future reputation, wanted to include that specialty in its
curriculum.
Aviation philanthropist Daniel Guggenheim was prevailed
upon to contribute.
e Guggenheim Aeronautical Laboratory, with a
tenfoot wind tunnel, began operation under von Kármán’s direction in 1930.
Caltech also courted Einstein.
So did Oxford and Columbia, but he was
attracted to the cosmological work of the dean of Caltech graduate studies, a
Massachusetts-born physicist of Quaker background named Richard Chace
Tolman.
Ongoing observations at Mount Wilson Observatory, above
Pasadena, might confirm the last of the three original predictions of the
general theory of relativity, the gravitational red-shiing of the light of high-
density stars.
Tolman sent a delegation to Berlin; Einstein agreed to visit
Pasadena in 1931 as a research associate.
He did, twice, returning to Berlin between, dining in Southern California
with Charlie Chaplin, viewing a rough cut of Sergei Eisenstein’s death-
obsessed film Que Viva Mexico!
with its sponsor Upton Sinclair.
As his
second visit approached, in December, Einstein was ready to reassess his
future: “I decided today,” he wrote in his diary, “that I shall essentially give
up my Berlin position and shall be a bird of passage for the rest of my
life.
”678
e bird of passage was not to nest in Pasadena.
Abraham Flexner, the
American educator, sought out Einstein at Caltech.
Flexner was in the
process of founding a new institution, not yet located or named, chartered in
1930 with a $5 million endowment.
e two men strolled for most of an
hour up and down the halls of the club where Einstein was staying.
ey
met again at Oxford in May and once more at the Einsteins’ summer house
at Caputh, outside Berlin, in June.
“We sat then on the veranda and talked
until evening,” Flexner recalled, “when Einstein invited me to stay to supper.
Aer supper we talked until almost eleven.
By that time it was perfectly clear
that Einstein and his wife were prepared to come to America.
”679 ey
walked together to the bus stop.
“Ich bin Feuer und Flamme dafür” Einstein
told his guest as he put him on the bus: “I am fire and flame for it.” 680, 681
e Institute for Advanced Study would be established in Princeton, New
Jersey.
Einstein was its first great acquisition.
He had suggested a salary of
$3,000 a year.
His wife and Flexner negotiated a more respectable $15,000.
It
was what Caltech had been prepared to pay.
But at Caltech, as in Zurich
before, Einstein would have been expected to teach.
At the Institute for
Advanced Study his only responsibility was thought.
e Einsteins le Caputh in December 1932, scheduled to divide the
coming year between Princeton and Berlin.
Einstein knew better.
“Turn
around,” he told his wife as they stepped off the porch of their house.
“You
will never see it again.
”682 She thought his pessimism foolish.
In mid-March the Nazi SA searched the empty house for hidden weapons.
By then Einstein had spoken out publicly against Hitler and was returning to
Europe to prepare to move.
He settled temporarily at a resort town on the
Belgian coast, Le Coq sur Mer, with his wife, his two stepdaughters, his
secretary, his assistant and two Belgian guards: assassination threatened
again.
In Berlin his son-in-law arranged to have his furniture packed.
e
French obligingly transported his personal papers to Paris by diplomatic
pouch.
At the end of March 1933 the most original physicist of the twentieth
century once again renounced his German citizenship.
Princeton University acquired John von Neumann and Eugene Wigner in
1930, in Wigner’s puckish recollection, as a package deal.
e university
sought advice on improving its science from Paul Ehrenfest, who
“recommended to them not to invite a single person but at least two...
who
already knew each other, who wouldn’t feel suddenly put on an island where
they have no intimate contact with anybody.
Johnny’s name was of course
well known by that time the world over, so they decided to invite Johnny
von Neumann.
ey looked: who wrote articles with John von Neumann?
ey found: Mr.
Wigner.
So they sent a telegram to me also.” 683 In fact,
Wigner had already earned a high reputation in a recondite area of physics
known as group theory, about which he published a book in 1931.
He
accepted the invitation to Princeton to look it over and perhaps to look
America over as well.
“ere was no question in the mind of any person that
the days of foreigners [in Germany], particularly with Jewish ancestry, were
numbered....
It was so obvious that you didn’t have to be perceptive....
It
was like, ‘Well, it will be colder in December.’ Yes, it will be.
We know it
well.” 684
Leo Szilard in Berlin debated his future in a musing letter to Eugene
Wigner written on October 8, 1932.685 He was apparently still trying to
organize his Bund: the knowledge had got into his blood that he had work to
accomplish at the moment more noble than science, he wrote—bad luck, it
couldn’t be distilled out again.
He understood he wasn’t allowed to complain
if such work commanded no office space in the world.
He was considering a
professorship in experimental physics in India since it would be essentially
only a teaching post and he could therefore turn his creative energies
elsewhere.
Only the gods knew what might be available in Europe or on the
American coast between Washington and Boston, places he might prefer, so
he perforce might go to India.
In any case, until he found a position he
would at least be free to do science without feeling guilty.
Szilard promised to write Wigner again when he had an “actual program.”
He did not yet know that his actual program would be organizing the
desperate rescue.
He parked his bags at the Harnack House in Dahlem and
sat down with Lise Meitner to talk about doing nuclear physics at the Kaiser
Wilhelm Institute.
She had Hahn, and Hahn was superb, but he was a
chemist.
She could use a jack-of-all-trades like Szilard.
But the collaboration
was not to be.
Events moved too quickly.
Szilard took his train from Berlin,
the train that proved him, if not more clever than most people, at least a day
earlier.
at was “close to the first of April, 1933.” 686
If Pauli, safe behind the lines in Zurich, had misread events before, he was
clear enough once the new law was announced.
Walter Elsasser, among the
first to leave, chose neutral Switzerland, entrained for Zurich and homed on
the physics building at the Polytechnic.
“On entering the main door of this
building one faces a broad and straight staircase leading directly to the
second floor.
Before I could take my first step on it, there appeared at the top
of the stairs the moon-face of Wolfgang Pauli, who shouted down: ‘Elsasser,’
he said, ‘you are the first to come up these stairs; I can see how in the
months to come there will be many, many more to climb up here.’ ”687 e
idea of a German dictatorship was no longer Quatsch.
Longstanding anti-Semitic discrimination in academic appointments
weighted the civil service law dismissals in favor of the natural sciences,
fields of study that had evolved more recently than the older disciplines of
the liberal arts, that German scholarship had looked down upon as
“materialistic” and that had therefore proved less impenetrable to Jews.688
Medicine incurred 423 dismissals, physics 106, mathematics 60—in the
physical and biological sciences other than medicine, an immediate total of
406 scientists.
e University of Berlin and the University of Frankfurt each
lost a third of its faculty.
e promising young theoretical physicist Hans Bethe, then at Tübingen,
first heard of his dismissal from one of his students, who wrote him to say he
read of it in the papers and wondered what he should do.
Bethe thought the
question impertinent—it was he who had been dismissed, not the student—
and asked for a copy of the news story.
Hans Geiger was professor of
experimental physics at Tübingen at the time, having moved there from
Berlin.
When Bethe joined the faculty as a theoretician in November 1932,
“Geiger explained his experiments to me, and in other ways made a lot of
me, so all seemed to be well on the personal level.” Sensibly, then, Bethe
wrote the vacationing Geiger for advice.
689, 690 “He wrote back a completely cold letter saying that with the changed situation it would be necessary to
dispense with my further services—period.
ere was no kind word, no
regret—nothing.
”691 A few days later the official notice arrived.
Bethe at twenty-seven was sturdy, indefatigable, a skier and mountain
climber, exceptionally self-confident in physics if still socially diffident.
692
His eyes were blue, his features Germanic; his thick, dark-brown hair, cut
short, stood up on his head like a brush.
His custom of plowing through
difficulties eventually won Bethe comparison with a battleship, except that
this particularly equable vessel usually boomed with laughter.
He had
already published important work.
Born in Strasbourg on July 2, 1906, Bethe moved during childhood to Kiel
and then to Frankfurt as his father, a university physiologist, achieved
increasing academic success.
He did not think of himself as a Jew: “I was not
Jewish.
693 My mother was Jewish, and until Hitler came that made no
difference whatever.” His father’s background was Protestant and Prussian;
his mother was the daughter of a Strasbourg professor of medicine.
He
counted two Jewish grandparents, more than enough to trigger the
Tübingen dismissal.
Bethe began university studies at Frankfurt in 1924.
Two years later,
recognizing his gi for theoretical work, his adviser sent him to Arnold
Sommerfeld in Munich.
Sommerfeld had trained nearly a third of the full
professors of theoretical physics in the German-speaking world; his protégés
included Max von Laue, Wolfgang Pauli and Werner Heisenberg.
e
American chemist Linus Pauling came to work with Sommerfeld while
Bethe was there, as did the German Rudolf Peierls and Americans Edward
U.
Condon and I.
I.
Rabi.
Edward Teller arrived from Karlsruhe in 1928, but
before the relationship between the two young men could develop into
friendship Teller was incapacitated in a streetcar accident, his right foot
severed just above the ankle.
By the time the amputation healed,
Sommerfeld had gone off on a sixtieth-birthday trip around the world,
leaving Bethe, who had just passed his doctoral examinations, to look for a
job on his own; missing Sommerfeld, Teller chose to move on to Leipzig to
study with Heisenberg.
Bethe went to the Cavendish on a Rockefeller
Fellowship, then to Rome, before accepting appointment at Tübingen.
Since Geiger refused to help challenge his Tübingen dismissal, Bethe
appealed to Munich.
“Sommerfeld immediately replied, ‘You are most
welcome here.
I will have your fellowship again for you.
Just come back.’ ”694
Aer a time in Munich Bethe was invited to Manchester, then to
Copenhagen to work with Bohr.
In the summer of 1934 Cornell University
offered him an assistant professorship.
One of his former students, now on
the Ithaca physics faculty, had recommended him for the post.
He accepted
and shipped for America, arriving in early February 1935.
Teller took his Ph.D.
under Heisenberg at Leipzig in 1930, stayed on there
for another year as a research associate, then shied to Göttingen to work in
its Institute for Physical Chemistry.
“His early papers,” Eugene Wigner
writes, “were entirely in the spirit of the times: the expanding world of the
applications of quantum mechanics.
”695 Teller probed the more developed
part of physics—chemical and molecular physics—with vigorous originality,
producing some thirty papers between 1930 and 1936, most of them written
with collaborators because he was sloppy at calculation and impatient with
the detailed effort of following through.
“It was a foregone conclusion that I had to leave,” Teller remembers.
“Aer
all, not only was I a Jew, I was not even a German citizen.
I wanted to be a
scientist.
e possibility to remain a scientist in Germany and to have any
chance of continuing to work had vanished with the coming of Hitler.
696 I
had to leave, as many others did, as soon as I could.” e director of his
institute, Arnold Eucken, “an old German nationalist,” confirmed Teller’s
conclusion as they le on the same southbound train for spring vacation in
March 1933.697 “I really want you here,” Teller remembers Eucken
equivocating, “but with this new situation, there is no point in your staying.
I would like to help you, but you have no future in Germany.
”698 e
problem then was where to go.
Back in Göttingen aer a tense confrontation
with his parents in Budapest—they wanted him to stay in Hungary—Teller
sat down to apply for a Rockefeller Fellowship to Copenhagen to work with
Bohr.
In Hamburg Otto Frisch decided he would have to take Hitler seriously
aer all.
Frisch, a personable young experimentalist with a gi for ingenious
invention, worked for Otto Stern, the tubby Galician who apprenticed under
Einstein and who had barked at Ernest Lawrence four years previously to get
busy on his notion of a cyclotron.
Stern was “quite shocked,” Frisch writes,
“to find that I was of Jewish origin, just as was he himself and another two of
his four collaborators.699 He would have to leave and the three of us as well,”
although “the University of Hamburg—with the traditions of a Free Hansa
city—was very reluctant to put the racial laws into effect, and I wasn’t sacked
until several months aer the other universities had toed the line.”
Before the Nazis promulgated the civil service law Frisch had applied for,
and won, a Rockefeller Fellowship to work with Enrico Fermi in Rome.
e
program was designed to free promising young scientists from their
immediate duties for a year of research abroad, aer which they were
expected to return to duty again.
At a time of crisis the foundation
unfortunately chose to enforce its rules narrowly.
Frisch was soon “very
disappointed and at first rather disgusted when [the foundation] told me
that, the situation having changed because of the Hitler laws, they had to
withdraw [their] offer of a grant because I no longer had a job to come back
to.
”700
In the meantime Bohr turned up in Hamburg.
He was traveling
throughout Germany to determine who needed help.
“To me it was a great
experience,” Frisch writes, “to be suddenly confronted with Niels Bohr—an
almost legendary name for me—and to see him smile at me like a kindly
father; he took me by my waistcoat button and said: ‘I hope you will come
and work with us sometime; we like people who can carry out “thought
experiments”!’ ” (Frisch had recently verified the prediction of quantum
theory that an atom recoils when it emits a photon, a movement previously
considered too slight to measure.) “at night I wrote home to my
mother...
and told her not to worry: the Good Lord himself had taken me
by my waistcoat button and smiled at me.
at was exactly how I felt.
”701
Stern, secure personally in independent wealth and international
reputation, set out to find places for his people.
“Stern said he would go
traveling,” continues Frisch, “and see if he could sell his Jewish collaborators
—I mean find places for them.
And he said he would try to sell me to
Madame Curie.
So I said, ‘Well, do what you can.
I’ll be very grateful for
anything you can do.
Just sell me to whoever wants to have me.’ And when
he came back [from visiting laboratories abroad] he said that Madame Curie
had not bought me, but Blackett had.
”702 Patrick Maynard Stuart Blackett,
London-born, tall, a Navy man, with a lean, vigorous face, was one of
Rutherford’s protégés and a future laureate.
He had just departed the
Cavendish for a workingmen’s college in London, Birkbeck, aer a furious
argument over the extent of the Cavendish teaching load.
“If physics
laboratories have to be run dictatorially,” Blackett had sworn, emerging
white-faced from Rutherford’s office, “I would rather be my own dictator.
”703
Birkbeck was a night school; experimenters could work at peace all day,
except when Blackett’s automatic cloud chamber, triggered by a passing
cosmic ray, went off like a cannon in their midst.
It was temporary duty.
Frisch took it.
When the appointment ran out the following year he crossed
the North Sea to Copenhagen to work with the Good Lord.
He had the comfort of knowing that for the immediate future his aunt was
safe.
Lise Meitner was forbidden as of the following September to lecture at
the University of Berlin, but because her citizenship was Austrian rather
than German she was allowed to continue her work at the KWI.
She had a
subterfuge to confess, however.
When Hahn, who had been lecturing on
radiochemistry that spring at Cornell, returned hurriedly to salvage what he
could from the wreckage of the Institutes’ staff, Meitner sought him out.
Her
nephew explains:
Lise Meitner had always kept quiet about her Jewish connection.
She had
never felt that she was in any way related to Jewish tradition.
Although
she was, racially speaking, a complete Jew, she had been baptized in her
infancy and had never considered herself as anything but a Protestant
who happened to have Jewish ancestors.
And when all this [anti-Semitic]
trouble began she felt, perhaps partly to let sleeping dogs lie and partly
not to embarrass her friends, that she would keep quiet about it.
It was
rather an embarrassment when Hitler forced it all out into the open, so to
say, and she had to go and tell Hahn, “You know, I am really Jewish and I
am apt to be an embarrassment to you.” 704
At Göttingen the Nobel laureate James Franck, a physical chemist, had a
talk with Niels Bohr.
ough Franck was Jewish, he was exempt from the
civil service law because he had fought at the front in the Great War.
He was
no less outraged.
e problem was deciding what to do.
He listened to many
people, but he told a friend long aerward that it was Bohr who persuaded
him: Bohr insisted that individuals really were responsible for the political
actions of their societies.
705 Franck was director of Göttingen’s Second
Physical Institute.
He resigned in protest on April 17 and made sure the
newspapers knew.
Max Born shared Franck’s convictions and admired his courage but
disliked public confrontation.706 Placed on indefinite “leave of absence” as of
April 25, but hearing from the university curator that arrangements might
eventually be made to reinstate him, Born responded brusquely that he
wanted no special treatment.
“We decided to leave Germany at once,” he
writes.
e Borns had already rented an apartment in an Alpine valley town
for the summer; they slipped the possession date forward and went early.
“us we le for the South Tyrol at the beginning of May.” 707 He passed the
news to Einstein via Leiden.
“Ehrenfest sent me your letter,” Einstein
responded on May 30 from Oxford, which was courting him.
“I am glad that
you have resigned your positions (you and Franck).
ank God there is no
risk involved for either of you.
But my heart aches at the thought of the
young ones.
”708
e young ones—the scientists and scholars just beginning to establish
themselves, as yet unpublished, without international reputation—needed
more than informal arrangements.
ey needed organized support.
* * *
Leo Szilard’s early train delivered him to Vienna, where he put up at the
Regina Hotel.
e news of the Law for the Restoration of the Professional
Civil Service reached him there, probably in the lobby, and he read the first
list of dismissals.
at outrage sent him into the street to walk.
He
encountered an old friend from Berlin, Jacob Marshack, an econometrician.
Szilard insisted they had to do something to help.
Together they went to see
Gottfried Kuhnwald—“the old, hunchbacked Jewish adviser of the Christian
Social party,” a Szilard admirer explains.
“Kuhnwald was a mysterious and
shrewd man, very Austrian, with sideburns like Franz Josef.
He agreed at
once that there would be a great expulsion.
He said that when it happened,
the French would pray for the victims, the British would organize their
rescue, and the Americans would pay for it.” 709
Kuhnwald sent the conspirators to a German economist then visiting
Vienna.
He advised them in turn that Sir William Beveridge, the director of
the London School of Economics, was also visiting Vienna at that time,
working on the history of prices, and was registered at the Regina.
Szilard
bearded the Englishman in his room and found he had not yet thought
further than the modest charity of appointing one dismissed economist to
the school.
at response was at least three orders of magnitude too timid
for Szilard’s taste and he prepared to assault Sir William with the truth.
Kuhnwald, Beveridge and Szilard met for tea and Szilard read out the list
of academic dismissals.
Beveridge then agreed, Szilard’s admirer writes, “that
as soon as he got back to England and got through the most important
things on his agenda, he would try to form a committee to find places for the
academic victims of Nazism; and he suggested that Szilard should come to
London and occasionally prod him.
If he prodded him long enough and
frequently enough, he would probably be able to do something.” 710
e busy economist required very little prodding.
Szilard followed him to
London and on a weekend at Cambridge in May Beveridge convinced
Ernest Rutherford to head an Academic Assistance Council.
e council
announced itself on May 22, proposing “to provide a clearing house and
centre of information” and to “seek to raise a fund.” Among the
distinguished academics who signed the announcement besides Beveridge
and Rutherford were J.
S.
Haldane, Gilbert Murray, A.
E.
Housman, J.
J.
omson, G.
M.
Trevelyan and John Maynard Keynes.
At about the same time a similar response was building in the United
States.
John Dewey helped assemble a Faculty Fellowship Fund at Columbia
University.
ere were other immediate private initiatives such as the hiring
of Hans Bethe at Cornell.
e major U.S.
effort, the Emergency Committee
in Aid of Displaced German Scholars, was organized under the auspices of
the Institute for International Education.711
Szilard beat the bushes that summer.
He did not feel he could properly
represent the Academic Assistance Council (though he ran its office for the
month of August as an upaid volunteer), so he traveled and worked to
coordinate existing groups and start new ones.
A “long and satisfactory
interview” early in May with Chaim Weizmann elicited support from
English Jewry.712 Einstein had thought of creating a “university for exiles”;
Szilard, working through Léon Rosenfeld, convinced him to devote his
prestige to the common effort instead.
713 In Switzerland he nudged the
International Students’ Service and the Intellectual Cooperation Section of
the League of Nations; in Holland he nudged a nervous and disorganized
Ehrenfest, who had a small fund available to support visiting theoretical
physicists.714 e university rectors in Belgium were “sympathetic,” Szilard
reported back to Beveridge, but “war reminiscences make it difficult to
establish in Belgium any organization for the helping of German
scientists.
”715
e Bohrs coordinated their own exhausting efforts with Szilard’s.
Bohr
convened his usual summer conference in Copenhagen, but this time, writes
Otto Frisch, “he proposed to use [it] as a sort of labour exchange.” Frisch
found it “a confusing affair, with so many people and so little time to sort
them out.
”716
It was Bohr with whom Edward Teller had hoped to work when he
applied in Göttingen for a Rockefeller Fellowship.
e foundation denied
him an award on the same grounds it had removed Otto Frisch’s: because he
had no place of employment to return to.
James Franck and Max Born
interceded on Teller’s behalf with the English, and shortly there arrived not
one but two offers of temporary appointments.
Teller accepted an
assistantship in physics at University College, London.
From there, at the
beginning of 1934, with the Rockefeller to secure him, he shied to
Copenhagen.
Szilard had help from an American, a Columbia University man, a
physicist named Benjamin Liebowitz who had invented a new kind of shirt
collar and established himself in the business of shirt manufacturing.
717 At
forty-two, Liebowitz was seven years older than Szilard.
e two men had
met when Szilard had visited the United States briefly in early 1932 and had
renewed their acquaintance aerward in Berlin.
Like Szilard, Liebowitz had
taken up unpaid relief work.
e two threw in together, the New Yorker
supplying Szilard with a useful American connection.
Liebowitz
characterized the German situation vividly in a letter back to New York in
early May:
It is impossible to describe the utter despair of all classes of Jews in
Germany.718 e thoroughness with which they are being hounded out
and stopped short in their careers is appalling.
Unless help comes from
the outside, there is no outlook for thousands, perhaps hundreds of
thousands, except starvation or [suicide].
It is a gigantic “cold pogrom”
and it is not only against Jews; Communists of course are included, but
are not singled out racially; Social Democrats and Liberals generally are
now or are coming under the ban, especially if they protest in the least
against the Nazi movement....
Dr.
Leo Szilard...
proved to be the best prognosticator—he was able to
foresee events better than anybody else I know.
Weeks before the storm
broke he began to formulate plans to provide some means of helping the
scientists and scholars of Germany.
Szilard was becoming nervous about his own lack of anchorage.
He had
not, he wrote another friend in August, “dismissed the idea of going to
India, neither has this idea grown stronger.
”719 He was not opposed to
America, but he would very much prefer to live in England.
Although he
was “rather tired,” he felt “very happy in England.” His happiness darkened
to gloom as soon as he looked ahead: “It is quite probable that Germany will
rearm and I do not believe that this will be stopped by intervention of other
powers within the next years.
erefore it is likely to have in a few years two
heavily armed antagonistic groups in Europe, and the consequence will be
that we shall get war automatically, probably against the wish of either of the
parties.” 720
at prepared him for that cool, humid, dull day in September when he
would step off the Southampton Row curb and begin to shape the things to
come.
* * *
Einstein crossed the Channel to England for the last time on September 9
and came under the flamboyant protection of a Naval Air Service
commander, barrister and M.P.
named Oliver Stillingfleet Locker-Lampson,
who had the peculiar distinction of having been invited, while serving under
the Grand Duke Nicholas of Russia, to murder Rasputin, an invitation
which uncharacteristic discretion led him to decline.721 Locker-Lampson
sent the distinguished physicist off the next morning to a vacation house
isolated on moorlands on the east coast of England.
Einstein had le
Belgium at his wife’s insistence: she feared for his life.
While she organized
their emigration he settled in at Roughton Heath, walking the moors
“talking to the goats,” he said.
722 ere he learned of the suicide of Paul
Ehrenfest, one of his oldest and closest friends, on September 25; Ehrenfest
had tried to kill his youngest son and blinded him and then killed himself.
e largest public event of the rescue was a mass meeting in Royal Albert
Hall, the great circular auditorium in London below Kensington Gardens.
Einstein was the featured speaker and therefore all the hall’s ten thousand
seats were filled and the aisles crowded.
Ernest Rutherford came down from
Cambridge to chair the event.
Aerward Einstein packed his bags and le
for America, joining his wife on the Westernland when it stopped at
Southampton on its way from Antwerp to New York, on October 7.
e mass meeting had been meant to raise money.
It raised very little.
Cambridge physicist P.
B.
Moon remembers Rutherford’s frustration:
He did a very great deal for the refugees from Hitler’s Germany, finding
places for some of them in his laboratory and scraping together what
money he could to keep them and their families going until they could
find established posts.
He told me that one of them had come to him and
said he had discovered something or other.
“I stopped him short and said
‘plenty of people know that,’ but you know, Moon, these chaps are living
on the smell of an oil rag.
ey’ve got to push themselves forward.
”723
With the possible exception of French prayer, in fact, Gottfried
Kuhnwald’s shrewd prediction held true for the first two years of the rescue
effort: the British alone nearly equaled the rest of the world in temporary
appointments, and American contributions, largely from foundations like
the Rockefeller, matched the rest dollar for dollar.724 , 725 en, as the Depression began to ease and the English academic system pinched,
emigration increased to the United States.
Under official Emergency
Committee auspices thirty scientists and scholars arrived in 1933, thirty-two
in 1934, only fieen in 1935; but forty-three came in 1938, ninety-seven in
1939, fiynine in 1940, fiy in 1941.726 Nor were many of these physicists:
with their international network of friendships and acquaintances the
physicists were better able than most to provide for each other.
About one
hundred refugee physicists emigrated to the United States between 1933 and
1941.
727
* * *
Princeton, Einstein reported to his friend Elizabeth, the Queen of Belgium,
“is a wonderful little spot, a quaint and ceremonious village of puny
demigods on stilts.
Yet, by ignoring certain social conventions, I have been
able to create for myself an atmosphere conducive to study and free from
distraction.” 728 Wigner noticed that von Neumann “fell in love with America
on the first day.
He thought: these are sane people who don’t talk in these
traditional terms which are meaningless.
To a certain extent the materialism
of the United States, which was greater than that of Europe, appealed to
him.” 729 When Stanislaw Ulam arrived in Princeton in 1935 he found von
Neumann comfortably ensconced in a “large and impressive house.
A black
servant let me in.” e von Neumanns gave two or three parties a week.
“ese were not completely carefree,” Ulam notes; “the shadow of coming
world events pervaded the social atmosphere.” 730 Ulam’s own enthusiasm for
America, formulated a few years later when he was a Junior Fellow at
Harvard, was tempered with a criticism of the extreme weather: “I used to
tell my friends that the United States was like the little child in a fairy tale, at
whose birth all the good fairies came bearing gis, and only one failed to
come.
It was the one bringing the climate.
”731
Leopold Infeld, riding the train through New Jersey from New York to
Princeton, “was astonished at so many wooden houses; in Europe they are
looked down upon as cheap substitutes which do not, like brick, resist the
attack of passing time.” Inevitably on that passage he noticed “old junked
cars, piles of scrap iron.” At Princeton the campus was deserted.
He found a
hotel and asked where all the students had gone.
Perhaps to see Notre Dame,
the clerk said.
“Was I crazy?” Infeld asked himself.
“Notre Dame is in Paris.
Here is Princeton with empty streets.
What does it all mean?” He soon
found out.
“Suddenly the whole atmosphere changed.
It happened in a
discontinuous way, in a split second.
Cars began to run, crowds of people
streamed through the streets, noisy students shouted and sang.” 732 Infeld
arrived on a Saturday; in those days Princeton played Notre Dame at
football.
His first night in the New World, Hans Bethe walked all over New York.733
A chemist, Kurt Mendelssohn, vividly recalled the morning aer his
escape: “When I woke up the sun was shining in my face.
I had slept deeply,
soundly and long—for the first time in many weeks.
[e previous night] I
had arrived in London and gone to bed without fear that at 3 a.m.
a car with
a couple of S.A.
men would draw up and take me away.
”734
Before it is science and career, before it is livelihood, before even it is
family or love, freedom is sound sleep and safety to notice the play of
morning sun.
8
Stirring and Digging735
e seventh Solvay Conference, held in Brussels in late October 1933, was
George Gamow’s ticket of escape from a Soviet Union rapidly becoming
inhospitable to theoretical physicists who persisted in modern views.
e
previous summer the tall, blond, powerfully built Odessan and his wife Rho,
also a physicist, had tried to escape by paddling a faltboat—a collapsible
rubber kayak—170 miles south from the Crimea to Turkey across the Black
Sea without benefit of a weather report.
ey took a pocket compass,
carefully hoarded hard-boiled eggs, cooking chocolate, two bottles of brandy
and a bag of fresh strawberries, set out in the morning ostensibly on a
recreational excursion and paddled hard all day and into the night.
e only
document they carried was Gamow’s Danish motorcycle-driver’s license,
souvenir of the 1930 winter he spent in Copenhagen aer working with
Rutherford at the Cavendish.
Gamow planned to show the Turks the
document, announce himself in Danish to be a Dane, head for the nearest
Danish consulate and put himself long-distance in Bohr’s capable hands.
But
the Black Sea is named for its storms.
e wind thwarted the Gamows’
escape, drenching them in heavy seas, exhausting them through a long, cold
night and finally blowing them back to shore.
736
Back in Leningrad the following year Gamow received notice from his
government that he was officially delegated to the Solvay Conference.
“I
could not believe my eyes,” he writes in his autobiography.737 It was an easy
way out of the country—except that Rho had not been included.
Gamow
determined to acquire a second passport or defiantly stay home.
rough
the Bolshevik economist Nikolai Bukharin, whom he knew, he arranged an
interview with Party Chairman Vyacheslav Molotov at the Kremlin.
Molotov
wondered that the theoretician could not live for two weeks without his wife.
Gamow feigned camaraderie:
“You see,” I said, “to make my request persuasive I should tell you that my
wife, being a physicist, acts as my scientific secretary, taking care of
papers, notes, and so on.
So I cannot attend a large congress like that
without her help.
But this is not true.
e point is that she has never been
abroad, and aer Brussels I want to take her to Paris to see the Louvre, the
Folies Bergère, and so forth, and to do some shopping.
”738
at Molotov understood.
“I don’t think this will be difficult to arrange,” he
told Gamow.
When the time arrived to collect the passports Gamow found that
Molotov had changed his mind, preferring not to set an awkward precedent.
Gamow stubbornly refused to cooperate.
e passport office called him
three times to pick up his passport and three times he insisted he would wait
until there were two.
e fourth time “the voice on the telephone informed
me that both passports were ready.
And indeed they were!” (Aer the
conference the young defectors sailed to America.
739 Gamow taught at the
University of Michigan’s summer school in pleasant Ann Arbor and from
there moved to accept a professorship at George Washington University in
Washington, D.C.)
e Solvay Conference, devoted for the first time to nuclear physics, drew
men and women from the highest ranks of two generations: Marie Curie,
Rutherford, Bohr, Lise Meitner among the older physicists; Heisenberg,
Pauli, Enrico Fermi, Chadwick (eight men in all from Cambridge and no
one from devastated Göttingen), Gamow, Irene and Frédéric JoliotCurie,
Patrick Blackett, Rudolf Peierls among the younger.
Ernest Lawrence, his
cyclotron humming, was the token American that year.
ey debated the structure of the proton.
Other topics they discussed may
have seemed more far-reaching at the time.
None would prove to be.
On
August 2, 1932, working with a carefully prepared cloud chamber, an
American experimentalist at Caltech named Carl Anderson had discovered
a new particle in a shower of cosmic rays.
e particle was an electron with a
positive instead of a negative charge, a “positron,” the first indication that the
universe consists not only of matter but of antimatter as well.
(Its discovery
earned Anderson the 1936 Nobel Prize.) Physicists everywhere immediately
looked through their files of cloud-chamber photographs and identified
positron tracks they had misidentified before (the Joliot-Curies, who had
missed the neutron, saw that they had also missed the positron).
e new
particle raised the possibility that the positively charged proton might in fact
be compound, might be not a unitary particle but a neutron in association
with a positron.
(It was not; there proved not to be room in the nucleus for
electrons positive or negative.)
Aer they had identified the positrons they had missed before, the Joliot-
Curies had started up their cloud chamber again and looked for the new
particle in other experimental arrangements.
ey found that if they
bombarded medium-weight elements with alpha particles from polonium,
the targets ejected protons.
en they noticed that lighter elements,
including in particular aluminum and boron, sometimes ejected a neutron
and then a positron instead of a proton.
at seemed evidence for a
compound proton.
ey presented their evidence with enthusiasm as a
report to the Solvay Conference.
Lise Meitner attacked the Joliot-Curies’ report.
She had performed similar
experiments at the KWI and she was highly respected for the cautious
precision of her work.
In her experiments, she emphasized, she had been
“unable to uncover a single neutron.
”740 Sentiment favored Meitner.
“In the
end, the great majority of the physicists present did not believe in the
accuracy of our experiments,” Joliot says.
“Aer the meeting we were feeling
rather depressed.” Fortunately the theoreticians intervened.
“But at that
moment Professor Niels Bohr took us aside...
and told us he thought our
results were very important.
A little later Pauli gave us similar
encouragement.” 741 e Joliot-Curies returned to Paris determined to settle
the issue once and for all.
Husband and wife were then thirty-three and thirty-six years old, with a
small daughter at home.
ey sailed and swam together in summer, skied
together in winter, worked together efficiently in the laboratory in the Latin
Quarter on the Rue Pierre Curie.
Irene had succeeded her mother as
director of the Radium Institute in 1932: the long-widowed pioneer was
mortally ill with leukemia induced by too many years of exposure to
radiation.
It seemed likely that the appearance of neutrons and positrons rather than
protons might depend on the energy of the alpha particles attacking the
target.
e Joliot-Curies could test that possibility by moving their polonium
source away from the target, slowing the alphas by forcing them to batter
their way through longer ranges of air.
Joliot went to work.
Without question
he was seeing neutrons.
When he shied the polonium away from the
aluminum-foil target “the emission of neutrons [ceased] altogether when a
minimum velocity [was] reached.” But something else happened then to
surprise him.
742 Aer neutron emission ceased, positron emission
continued—not stopping abruptly but decreasing “only over a period of
time, like the radiation...
from a naturally radioactive element.” What was
going on?
Joliot had been observing the particles with a cloud chamber,
catching their ionizing tracks in its supersaturated fog.
Now he switched to a
Geiger counter and called in Irene.
As he explained to a colleague the next
day: “I irradiate this target with alpha rays from my source; you can hear the
Geiger counter crackling.
I remove the source: the crackling ought to stop,
but in fact it continues.
”743 e strange activity declined to half its initial intensity in about three minutes.
ey would hardly yet have dared to think
of that period as a half-life.
It might merely mark the erratic performance of
the Geiger counter.
A young German physicist who specialized in Geiger counters, Wolfgang
Gentner, was working at the institute that year.
Joliot asked him to check the
lab instruments.
e couple went off to a social evening they could find no
excuse to avoid.
“e following morning,” writes the colleague to whom
Joliot spoke that day, “the Joliots found on their desk a little hand-written
note from Gentner, telling them that the Geiger counters were in perfect
working order.” 744
ey were nearly certain then that they had discovered how to make
matter radioactive by artificial means.
ey calculated the probable reaction.
An aluminum nucleus of 13
protons and 14 neutrons, capturing an alpha particle of 2 protons and 2
neutrons and immediately re-emitting 1 neutron must be converting itself
into an unstable isotope of phosphorus with 15 protons and 15 neutrons (13
+ 2 protons = 15; 14 + 2 - 1 neutrons = 15).
e phosphorus then probably
decayed to silicon (14 protons, 16 neutrons).
e 3-minute period was the
half-life of that decay.
ey could not chemically trace the infinitesimal accumulation of silicon.
Joliot explained why in 1935, when he and his wife accepted the Nobel Prize
in Chemistry for their discovery: “e yield of these transmutations is very
small, and the weights of elements formed...
are less than 10-15 [grams],
representing at most a few million atoms”—too few to find by chemical
reaction alone.745 But they could trace the radioactivity of the phosphorus
with a Geiger counter.
If it did indeed signal the artificial transmutation of
some of the aluminum to phosphorus, they should be able to separate the
two different elements chemically.
e radioactivity would go with the new
phosphorus and leave the untransmuted aluminum behind.
But they needed
a definitive separation that could be carried out within three minutes, before
the faint induced radioactivity faded below their Geiger counter’s threshold.
e request perplexed a chemist in a nearby laboratory—“never having
envisaged chemistry from that point of view,” says Joliot—but he contrived
the necessary procedure.
746 e Joliot-Curies irradiated a piece of aluminum
foil, dropped it into a container of hydrochloric acid and covered the
container.
e acid dissolved the foil, producing, by reaction, gaseous
hydrogen, which should carry the phosphorus with it out of solution.
ey
drew off the gas into an inverted test tube.
e dissolved aluminum fell
silent then but the gas made the Geiger counter chatter: whatever was
radioactive had been carried along.
A different chemical test proved that the
radioactive substance was phosphorus.
Joliot bounded like a boy.
e discovery might serve as an offering to Irène’s ailing mother, who had
prepared the daughter and sponsored the son-in-law:
Marie Curie saw our research work and I will never forget the expression
of intense joy which came over her when Irene and I showed her the first
artificially radioactive element in a little glass tube.
I can still see her
taking in her fingers (which were already burnt with radium) this little
tube containing the radioactive compound—as yet one in which the
activity was very weak.
To verify what we had told her she held it near a
Geiger-Müller counter and she could hear the rate meter giving off a great
many “clicks.” is was doubtless the last great satisfaction of her life.747
e Joliot-Curies reported their work—“one of the most important
discoveries of the century,” Emilio Segrè says in his history of modern
physics—in the Comptes Rendus on January 15, 1934, and in a letter to
Nature dated four days later.748 “ese experiments give the first chemical
proof of artificial transmutation,” they concluded proudly.
749 Rutherford
wrote them within a fortnight: “I congratulate you both on a fine piece of
work which I am sure will ultimately prove of much importance.” He had
tried a number of such experiments himself, he said, “but without any
success”—high praise from the master of experiment.750
ey had demonstrated that it was possible not only to chip pieces off the
nucleus, as Rutherford had done, but also to force it artificially to release
some of its energy in radioactive decay.
Joliot foresaw the potential
consequences of that attack in his half of the joint Nobel Prize address.
Given the progress of science, he said, “we are entitled to think that
scientists, building up or shattering elements at will, will be able to bring
about transmutations of an explosive type....
If such transmutations do
succeed in spreading in matter, the enormous liberation of useful energy can
be imagined.” But he saw the possibility of cataclysm “if the contagion
spreads to all the elements of our planet”:751
Astronomers sometimes observe that a star of medium magnitude
increases suddenly in size; a star invisible to the naked eye may become
very brilliant and visible without any telescope—the appearance of a
Nova.
is sudden flaring up of the star is perhaps due to transmutations
of an explosive character like those which our wandering imagination is
perceiving now—a process that the investigators will no doubt attempt to
realize while taking, we hope, the necessary precautions.
Leo Szilard received no invitation to the Solvay Conference.
By October
1933 he had not accomplished any nuclear physics of note except within the
well-equipped laboratory of his brain.
In August he had written a friend that
he was “spending much money at present for travelling about and earn of
course nothing and cannot possibly go on with this for very long.
”752 e
idea of a nuclear chain reaction “became a sort of obsession” with him.
When he heard of the Joliot-Curies’ discovery, in January, his obsession
bloomed: “I suddenly saw that the tools were on hand to explore the
possibility of such a chain reaction.” 753
He moved to a less expensive hotel, the Strand Palace, near Trafalgar
Square, and settled in to think.
He had “a little money saved up” aer all,
“enough perhaps to live for a year in the style in which I was accustomed to
live, and therefore I was in no particular hurry to look for a job”—the
excitement of new ideas thus relieving his August urgency.754 e bath was
down the hall.
“I remember that I went into my bath...
around nine o’clock
in the morning.
ere is no place as good to think as a bathtub.
I would just
soak there and think, and around twelve o’clock the maid would knock and
say, ‘Are you all right, sir?’ en I usually got out and made a few notes,
dictated a few memoranda.” 755
One of the “memoranda” took the form of a patent application, filed
March 12, 1934, relating to atomic energy.
756, 757 It was the first of several, that year and the next, all finally merged into one complete specification,
“Improvements in or Relating to the Transmutation of Chemical Elements.”
(e same day Szilard applied for a patent, never issued, proposing the
storage of books on microfilm.
758) Szilard had already realized—in
September, in the context of inducing a chain reaction—that neutrons would
be more efficient than alpha particles at bombarding nuclei.
He applied that
insight now to propose an alternative method for creating artificial
radioactivity:
In accordance with the present invention radio-active bodies are
generated by bombarding suitable elements with neutrons....
Such
uncharged nuclei penetrate even substances containing the heavier
elements without ionization losses and cause the formation of radio-active
substances.
759
at was a first step.
It was also a cheeky piece of bravado.
Szilard had only
theoretical grounds for believing that neutrons might induce radioactivity
artificially.
He had not done the necessary experiments.
Only the Joliot-
Curies had carried out such experiments so far, and they used alpha
particles.
Szilard was pursuing more than artificial radioactivity.
He was
pursuing chain reactions, power generation, atomic bombs.
He had not yet
found patentable form for these excursions.
He wondered which element or
elements might emit two or more neutrons for each neutron captured.
He
decided at some point, he said later, “that the reasonable thing to do would
be to investigate systematically all the elements.
ere were ninety-two of
them.
But of course this is a rather boring task, so I thought that I would get
some money, have some apparatus built, and then hire somebody who
would just sit down and go through one element aer the other.
”760
e task would hardly be boring.
e truth is that Szilard lacked the
resources for such work—access to a laboratory, a dedicated crew, sufficient
financial support.
“None of the physicists had any enthusiasm for this idea of
a chain reaction,” he would remember.
Rutherford threw him out.
Blackett
told him, “Look, you will have no luck with such fantastic ideas in
England.
761 Yes, perhaps in Russia.
If a Russian physicist went to the
government and [said], ‘We must make a chain reaction,’ they would give
him all the money and facilities which he would need.
But you won’t get it in
England.” Soaking in his bath against the London chill, Szilard turned back
to mapping the future.
e opportunity to explore the elements
systematically for surprises by bombarding them with neutrons passed him
by.
* * *
It fell instead to Enrico Fermi and his team of young colleagues in Rome.
Fermi was prepared.
762 He had all on hand that Szilard did not.
He saw as
soon as Szilard that the neutron would serve better than the alpha particle
for nuclear bombardment.
e point was not obvious.
One used alphas to
generate neutrons (as the Joliot-Curies had done along the way to chasing
down their positrons).
Since not all the alphas found targets, the neutral
particles were correspondingly that much more scarce.
As Otto Frisch
would write: “I remember that my reaction and probably that of many
others was that Fermi’s was really a silly experiment because neutrons were
much fewer than alpha particles.
What that simple argument overlooked of
course was that they are very much more effective.” 763
Fermi was prepared because he had been organizing his laboratory for a
major expedition into nuclear physics for more than four years.
If Italy had
been one of the hot centers of physical research he might have been too
preoccupied to plan ahead so carefully.
But Italian physics was a ruin as sere
as Pompeii when he came to it.
He had no choice but to push aside the
debris and start fresh.
Both Fermi’s biographers—his wife Laura and his protégé and fellow
Nobel laureate Emilio Segrè—assign the beginning of his commitment to
physics to the period of psychological trauma following the death of his
older brother Giulio when Fermi was fourteen years old, in the winter of
1915.
764 Only a year apart in age, the two boys had been inseparable; Giulio’s
death during minor surgery for a throat abscess le Enrico suddenly bere.
at same winter young Enrico browsed on market day among the stalls
of Rome’s Campo dei Fiori, where a statue commemorates the philosopher
Giordano Bruno, Copernicus’ defender, who was burned at the stake there
in 1600 by the Inquisition.
Fermi found two used volumes in Latin,
Elementorum physicae mathematicae, the work of a Jesuit physicist,
published in 1840.
e desolate boy used his allowance to buy the physics
textbooks and carried them home.
ey excited him enough that he read
them straight through.
When he was finished he told his older sister Maria
he had not even noticed they were written in Latin.
“Fermi must have
studied the treatise very thoroughly,” Segrè would decide, looking through
the old volumes many years later, “because it contains marginal notes,
corrections of errors, and several scraps of paper with notes in Fermi’s
handwriting.
”765
From that point forward Fermi’s development as a physicist proceeded,
with a single significant exception, rapidly and smoothly.
A friend of his
father, an engineer named Adolfo Amidei, guided his adolescent
mathematical and physical studies, lending him texts in algebra,
trigonometry, analytical geometry, calculus and theoretical mechanics
between 1914 and 1917.
When Enrico graduated from the liceo early,
skipping his third year, Amidei asked him if he preferred mathematics or
physics as a career and made a point of writing down, with emphasis, the
young man’s exact reply: “I studied mathematics with passion because I
considered it necessary for the study of physics, to which I want to dedicate
myself exclusively....
I’ve read all the best-known books of physics.
”766
Amidei then advised Fermi to enroll not at the University of Rome but at
the University of Pisa, because he could compete in Pisa to be admitted as a
fellow to an affiliated Scuola Normale Superiore of international reputation
that would pay his room and board.
Among other reasons for the advice,
Amidei told Segrè, he wanted to remove Fermi from his family home, where
“a very depressing atmosphere prevailed...
aer Giulio’s death.” 767
When the Scuola Normale examiner saw Fermi’s competition essay on the
assigned theme “Characteristics of sound” he was stunned.
It set forth,
reports Segrè, “the partial differential equation of a vibrating rod, which
Fermi solved by Fourier analysis, finding the eigenvalues and the
eigenfrequencies...
which would have been creditable for a doctoral
examination.” 768 Calling in the seventeen-year-old liceo graduate, the
examiner told him he was extraordinary and predicted he would become an
important scientist.
By 1920 Fermi could write a friend that he had reached
the point of teaching his Pisa teachers: “In the physics department I am
slowly becoming the most influential authority.
In fact, one of these days I
shall hold (in the presence of several magnates) a lecture on quantum
theory, of which I’m always a great propagandist.” 769 He worked out his first
theory of permanent value to physics while he was still a student in Pisa, a
predictive deduction in general relativity.
e exception to his rapid progress came in the winter of 1923, when
Fermi won a postdoctoral fellowship to travel to Göttingen to study under
Max Born.
Wolfgang Pauli was there then, and Werner Heisenberg and the
brilliant young theoretician Pascual Jordan, but somehow Fermi’s
exceptional ability went unnoticed and he found himself ignored.
Since he
was, in Segrè’s phrase, “shy, proud, and accustomed to solitude,” he may have
brought the ostracism on himself.
770 Or the Germans may have been
prejudiced against him by Italy’s poor reputation in physics.
Or, more
dynamically, Fermi’s visceral aversion to philosophy may have le him
tongue-tied: he “could not penetrate Heisenberg’s early papers on quantum
mechanics, not because of any mathematical difficulties, but because the
physical concepts were alien to him and seemed somewhat nebulous” and he
wrote papers in Göttingen “he could just as well have written in Rome.
”771,
772 Segrè has concluded that “Fermi remembered Göttingen as a sort of
failure.
He was there for a few months.
He sat aside at his table and did his
work.
He didn’t profit.
ey didn’t recognize him.
”773 e following year
Paul Ehrenfest sent along praise through the intermediary of a former
student who looked up Fermi in Rome.
A three-month fellowship then took
the young Italian to Leiden for the traditional Ehrenfest tightening.
Aer
that Fermi could be sure of his worth.
He was always averse to philosophical physics; a rigorous simplicity, an
insistence on concreteness, became the hallmark of his style.
Segrè thought
him inclined “toward concrete questions verifiable by direct experiment.
”774
Wigner noticed that Fermi “disliked complicated theories and avoided them
as much as possible.” 775 Bethe remarked Fermi’s “enlightening simplicity.
”776
Less generously, the sharp-tongued Pauli called him a “quantum engineer”;
Victor Weisskopf, though an admirer, saw some truth in Pauli’s canard, a
difference in style from more philosophical originals like Bohr.
777 “Not a
philosopher,” Robert Oppenheimer once sketched him.778 “Passion for clarity.
He was simply unable to let things be foggy.
Since they always are,
this kept him pretty active.” An American physicist who worked with the
middle-aged Fermi thought him “cold and clear....
Maybe a little ruthless
in the way he would go directly to the facts in deciding any question,
tending to disdain or ignore the vague laws of human nature.
”779
Fermi’s passion for clarity was also a passion to quantify.
He seems to have
attempted to quantify everything within reach, as if he was only comfortable
when phenomena and relationships could be classified or numbered.
“Fermi’s thumb was his always ready yardstick,” Laura Fermi writes.
“By
placing it near his le eye and closing his right, he would measure the
distance of a range of mountains, the height of a tree, even the speed at
which a bird was flying.
”780 His love of classification “was inborn,” Laura
Fermi concludes, “and I have heard him ‘arrange people’ according to their
height, looks, wealth, or even sex appeal.” 781
Fermi was born in Rome on September 29, 1901, into a family that had
successfully made the transition during the nineteenth century from peasant
agriculture in the Po Valley to career civil service with the Italian national
railroad.
His father was a capo divisione in the railroad’s administration, a
civil rank that corresponded to the military rank of brigadier general.
In
accord with a common Italian practice of the day, the infant Enrico was sent
to live in the country with a wet nurse.
So was his brother Giulio, but
because Enrico’s health was delicate he did not return to his mother and
father until he was two and a half years old.
Confronted then with a roomful
of strangers purporting to be his family, and “perhaps,” writes Laura Fermi,
“missing the rough effusiveness of his nurse,” he began to cry:782
His mother talked to him in a firm voice and asked him to stop at once; in
this home naughty boys were not tolerated.
Immediately the child
complied, dried his tears, and fussed no longer.
en, as in later
childhood, he assumed the attitude that there is no point in fighting
authority.
If they wanted him to behave that way, all right, he would; it was
easier to go along with them than against.
In 1926, when he was twenty-five years old, Fermi was chosen under the
Italian system of concorsos, national competitions, to become professor of
theoretical physics at the University of Rome.
An influential patron had seen
to the creation of the new post, a Sicilian named Orso Mario Corbino, a
short, dark, volatile man, forty-six when Fermi sought him out in 1921, the
director of the university physics institute, an exceptional physicist and a
Senator of the Kingdom.
Since the old guard of Italian physicists resented
Fermi’s rapid promotion, he especially welcomed the protection of Corbino’s
patronage.
Corbino found support for his efforts to improve Italian physics
from the Fascist government of the bulletheaded former journalist Benito
Mussolini, although the senator was not himself a party member.
In the later 1920s Corbino and his young professor agreed that the time
was ripe for the small group they were assembling in Rome to colonize new
territory on the frontier of physics.783 ey chose as their territory the
atomic nucleus, then finding description in quantum mechanics but not yet
experimentally disassembled.
Fermi’s tall, erudite Pisa classmate Franco
Rasetti signed on as Corbino’s first assistant early in 1927.
Rasetti and Fermi
together recruited Segrè, who had been studying engineering, by taking him
along to the Como conference and explaining the achievements of the
assembled luminaries to him—by then, Segrè saw, Pauli and Heisenberg
recognized Fermi’s talents and included him among their friends.
e son of
the prosperous owner of a paper mill, Segrè contributed elegance to the
group as well as brains.
Corbino added Edoardo Amaldi, the son of a mathematics professor at
the University of Padua, by frankly raiding the engineering school.
e
group quickly nicknamed Fermi “the Pope” for his quantum infallibility;
Corbino, like Rutherford at the Cavendish, called them all his “boys.” Rasetti
departed to Caltech, Segrè to Amsterdam, for seasoning.
Fermi sent them
out again in the early 1930s, aer the decision to go into nuclear physics:
Segrè to work with Otto Stern in Hamburg, Amaldi to Leipzig to the
laboratory of the physical chemist Peter Debye, Rasetti to Lise Meitner at the
KWI.
By 1933, with a departmental budget above $2,000 a year, ten times
the budget of most Italian physics departments, with a well-made cloud
chamber and a nearby radium source and KWI training in the vagaries of
Geiger counters, the group was ready to begin.
In the meantime, two months aer the Solvay Conference, Fermi
completed the major theoretical work of his life, a fundamental paper on
beta decay.
Beta decay, the creation and expulsion by the nucleus of
highenergy electrons in the course of radioactive change, had needed a
detailed, quantitative theory, and Fermi supplied it entire.
He introduced a
new type of force, the “weak interaction,” completing the four basic forces
known in nature: gravity and electromagnetism, which operate at long
range, and the strong force and Fermi’s weak force, which operate within
nuclear dimensions.
He introduced a new fundamental constant, now called
the Fermi constant, determining it from existing experimental data.
“A
fantastic paper,” Victor Weisskopf later praised it, “...
a monument to
Fermi’s intuition.
”784 In London the editor of Nature rejected it on the grounds that it was too remote from physical reality, which Fermi found
irritating but amusing; he published it instead in the little-known weekly
journal of the Italian Research Council, Ricerca Scientifica, where Amaldi’s
wife Ginestra worked, and later in the Zeitschri fúr Physik.
785, 786 With only minor adjustments Fermi’s theory of beta decay continues to be definitive.
e Comptes Rendus reporting the Joliot-Curies’ discovery of artificial
radioactivity reached Rome shortly aer Fermi returned from skiing in the
Alps, in January 1934.
787 “We had not yet found any [nuclear physics]
problems to work on,” Amaldi reminisces.
“...
en came out the paper of
Joliot, and Fermi immediately started to look for the radioactivity.
”788 Like
Szilard, Fermi saw the advantages of using neutrons.
I.
I.
Rabi catalogues
those advantages in a lecture:
Since the neutron carries no charge, there is no strong electrical repulsion
to prevent its entry into nuclei.
In fact, the forces of attraction which hold
nuclei together may pull the neutron into the nucleus.
When a neutron
enters a nucleus, the effects are about as catastrophic as if the moon struck
the earth.
e nucleus is violently shaken up by the blow, especially if the
collision results in the capture of the neutron.
A large increase in energy
occurs and must be dissipated, and this may happen in a variety of ways,
all of them interesting.
789
When Fermi began his neutron-bombardment experiments he was thirty-
three years old, short, muscular, dark, with thick black hair, a narrow nose
and surprising gray-blue eyes.
His voice was deep and he grinned easily.
Marriage to the petitely beautiful Laura Capon, the daughter of a Jewish
officer in the Italian Navy, had encouraged him in methodical habits: he
worked for several hours privately at home, arrived at the physics institute at
nine, worked until twelve-thirty, lunched at home, returned to the institute
at four and continued work until eight in the evening, returning home then
for dinner.
With marriage he had also gained weight.
He and his team of young colleagues occupied the south section of the
second floor of the institute, sharing the space with Corbino and with the
chief physicist of Rome’s Sanitá Pubblica—its health department—a
generous soul named G.
C.
Trabacchi who lent Corbino’s boys some of the
instruments and supplies they needed for their experiments (in return they
cherished him, nicknaming him “Divine Providence”).
Antonino Lo Sordo,
a frustrated old-guard physicist, fended off the encroaching horde from an
office at the north end of the floor.
Corbino and his family lived above, the
residence overlooking a private garden in back with a goldfish pond at its
focus.
e first floor served students; the basement held electrical generators
and a lead-lined safe for the Sanitá’s gram of radium, worth 670,000 lire—
about $34,000—in that year of its most historic use.
Glass pipes passed
through a wall of the special safe to carry radon, formed in the decay of
radium, to a compact extraction plant, a modest refinery of glasspipe towers
that purified and dried the radioactive gas.
e residential upper story of the
institute, contracted above the longer lower floors to make room at one end
for the dome of a small rotunda, was roofed with tile.
“e location of the
building in a small park on a hill near the central part of Rome was
convenient and beautiful at the same time,” Segrè recalls.
“e garden,
landscaped with palm trees and bamboo thickets, with its prevailing silence
(except at dusk, when gatherings of sparrows populated the greenery), made
the institute a most peaceful and attractive center of study.
”790 A gravel path
that shone white in the golden Roman sun led down to the Via Panisperna.
As usual, Fermi hewed the neutron experiments by hand.
In February and
early March he personally assembled crude Geiger counters from aluminum
cylinders acquired by cutting the bottoms off tubes of medicinal tablets.
791
Wired, filled with gas, their ends sealed and leads attached, the counters
were slightly smaller than rolls of breath mints and a hundred times less
efficient than modern commercial units, but with Fermi to operate them
they served.
While he built Geiger counters he asked Rasetti to prepare a
neutron source in the form of polonium evaporated onto beryllium.
Since
polonium emits relatively low-energy alpha particles, the resulting source
emitted relatively few neutrons per second, and Fermi and Rasetti irradiated
several samples without success.
At that point Rasetti, showing a surprising lack of eagerness for historic
experiment, went off to Morocco for Easter vacation.
Fermi cast about for
some way to acquire a stronger neutron source.
e rationale for using
polonium in the first place, in Paris and Cambridge and Berlin as well as in
Rome, had been that a stronger alpha emitter like radon also emitted strong
beta and gamma radiation, which disturbed the instruments and interfered
with measurements.
Fermi realized suddenly that since he was trying to
observe a delayed effect, he was measuring only aer he removed the
neutron source in any case—and therefore any beta and gamma radiation
wouldn’t matter and he could use radon.
Trabacchi had the radon to spare
and willingly dispensed it; with a half-life of only 3.82 days it was perishable
in any case and his glowing gram of radium continually exhaled a fresh
dra.
To the basement of the physics institute on the Via Panisperna, in his gray
lab coat, in mid-March, Fermi thus carried a snippet of glass tubing no
larger than the first joint of his little finger.
It was flame-sealed at one end
and partly filled with powdered beryllium.
He set the sealed end of this
capsule into a container of liquid air.
e radon, directed from the outlet of
the extraction plant into the capsule, condensed on its walls in the—200 °C
cold.
Fermi then had to attempt quickly to heat and draw closed the other
end of the capsule, without cracking the glass, before the radon evaporated
and escaped.
When he succeeded, he finished preparing the neutron source
by dropping it into a two-foot length of glass tubing of larger diameter and
sealing it into the far end so that it could be handled at a distance safe from
dangerous exposure to its gamma rays.
For all the tedious preparation its
useful life was brief.
In the beginning Fermi worked alone.
He intended eventually to irradiate
most of the elements in the periodic table and he started methodically with
the lightest.
His source, he calculated, supplied him with more than 100,000
neutrons per second.
792 “Small cylindrical containers filled with the
substances tested,” he would explain in his first report, “were subjected to
the action of the radiation from this source during intervals of time varying
from several minutes to several hours.
”793 Fermi first irradiated water—
testing hydrogen and oxygen at the same time—then lithium, beryllium,
boron and carbon without inducing them to radioactivity.
Laura Fermi says
he wavered then, discouraged by the lack of results, but Fermi seldom talked
shop at home and doubt seems unlikely: he knew from the Joliot-Curie work
that aluminum, a little farther along, reacted with alphas, and neutrons
should prove even more effective.
In any case he succeeded on his next attempt, with fluorine: “Calcium
fluoride, irradiated for a few minutes and rapidly brought into the vicinity of
the counter, causes in the first few moments an increase of pulses; the effect
decreases rapidly, reaching the half-value in about 10 seconds.”
Soon he found a radioactivity in aluminum with a half-life of twelve
minutes, different from the Joliot-Curies’ discovery.
Putting aluminum first
to link his work with theirs, he reported his findings in a letter to the Ricerca
Scientifica on March 25, 1934.
A Roman numeral I distinguishes that first report on “Radioactivity
induced by neutron bombardment.” e search was on.
To move it along
Fermi recruited Amaldi and Segrè and cabled Rasetti in Morocco to rush
home.
Segrè writes:
We organized our activities this way: Fermi would do a good part of the
experiments and calculations.
Amaldi would take care of what we would
now call the electronics, and I would secure the substances to be
irradiated, the sources, etc.
Now, of course, this division of labor was by
no means rigid, and we all participated in all phases of the work, but we
had a certain division of responsibility along these lines, and we
proceeded at great speed.
We needed all the help we could get, and we
even enlisted the help of a younger brother of one of the students
(probably 12 years old), persuading him that it was most interesting and
important that he should prepare some neat paper cylinders in which we
could irradiate our stuff.
794
e next letter that went to the Ricerca Scientifica (and in summary form
to Nature) reported artificially induced radioactivity in iron, silicon,
phosphorus, chlorine, vanadium, copper, arsenic, silver, tellurium, iodine,
chromium, barium, sodium, magnesium, titanium, zinc, selenium,
antimony, bromine and lanthanum.
795 By then they had established a
routine: they irradiated substances at one end of the second floor and tested
them under the Geiger counters at the other end, down a long hall.
at
shielded the counters from stray radiation from the neutron source.
But it
also meant, whenever the half-life of an induced radioactivity was short, that
someone had to run down the hall.
“Amaldi and Fermi prided themselves on
being the fastest runners,” Laura Fermi notes, “and theirs was the task of
speeding short-lived substances from one end of the corridor to the other.
ey always raced, and Enrico claims that he could run faster than Edoardo.
But he is not a good loser.” 796 A dignified Spaniard showed up one day to
confer with “His Excellency Fermi.” Rome’s young professor of theoretical
physics, a dirty lab coat flying out behind him, nearly knocked the visitor
down.
ey came, finally, to uranium.
ey had roughly classified the effects they
were seeing.
Light elements generally transmuted to lighter elements by
ejecting either a proton or an alpha particle.
But the electrical barrier around
the nucleus works against exits as well as entrances, and that barrier
increases in strength with increasing atomic number.
So heavy elements got
heavier, not lighter: they captured the bombarding neutron, threw off its
binding energy by emitting gamma radiation, and thus, with the addition of
the neutron’s mass, but with no added or subtracted charge, became a
heavier isotope of themselves.
Which then decayed by the delayed emission
of a negative beta ray to an element with one more unit of atomic number.
Uranium did the same; aer a delay it emitted a beta electron.
at should
mean, Fermi realized, that bombarding uranium with neutrons was
producing first a heavier isotope, uranium 239, and then a new, man-made
transuranic element, atomic number 93, something never seen on earth
before.
It was necessary to purify their uranium sample (uranium nitrate in
solution, a light yellow liquid) of the obscuring beta activity its natural decay
products gave off.
(Uranium decays naturally through a series of fourteen
complex steps down the periodic table to thorium, protactinium, radium,
radon, polonium and bismuth to lead.) Trabacchi in his generosity had by
then even lent the group a young chemist, Oscar D’Agostino, fresh from
training in radiochemistry on the Rue Pierre Curie; D’Agostino
accomplished the laborious purification in early May.
ey were using
stronger sources now, up to 800 millicuries of radon, about a million
neutrons per second.
797 Irradiating the uranium nitrate gave “a very intense
effect with several periods [of half-lives]: one period of about 1 minute,
another of 13 minutes besides longer periods not yet exactly determined”—
thus their May 10 report.
798
ese several induced radioactivities were all beta emitters.
ey made
whatever atom was emitting them heavier by one atomic number.
It seemed
to follow, then, that they were transmutations up the periodic table into the
uncharted new region of man-made elements.
To confirm that stunning
possibility Fermi needed to demonstrate with chemical separations that the
neutron bombardment was not unaccountably creating elements lighter than
uranium.
e one-minute half-life was too short to work with, so he
concentrated on the thirteen-minute substance.
D’Agostino diluted the
irradiated uranium nitrate with 50 percent nitric acid, dissolved into the
acid a small amount of manganese salt and set the solution to boil.
By
adding sodium chlorate to the boiling solution he precipitated crystals of
manganese dioxide.
When he filtered the crystals from the solution the
radioactivity went with the manganese, much as the radioactivity the Joliot-
Curies had induced in aluminum went off with the hydrogen gas.
If the
radioactivity could be precipitated out of the uranium solution along with a
manganese carrier, then it must not be uranium anymore.
By adding other carriers and precipitating other compounds D’Agostino
proved that the thirteen-minute substance was neither protactinium (91),
thorium (90), actinium (89), radium (88), bismuth (83) nor lead (82).
Its
behavior excluded elements 87 (then known as ekacesium), and 86 (radon).
Element 85 was unknown.
Perhaps because the half-lives were different,
Fermi made no attempt to check polonium (84).
But he felt he had been
sufficiently thorough.
“is negative evidence about the identity of the 13
min-activity from a large number of heavy elements,” he reported cautiously
in Nature in June, “suggests the possibility that the atomic number of the
element may be greater than 92.
”799
Corbino injudiciously announced “a new element” at the annual
convocation, the King of Italy in attendance, that closed the academic year,
which set the press baying and gave Fermi a few sleepless nights.
800 Having
so splendidly accomplished Szilard’s “rather boring task,” the weary physicist
was happy to depart aer that with his wife and their small daughter Nella
for a summer lecture tour sponsored by the Italian government through
Argentina, Uruguay and Brazil.
* * *
Leo Szilard had emerged from his bath that spring of 1934 to pursue his
favorite causes, not yet joined, of releasing the energy of the nucleus and of
saving the world.
In a late-April memorandum condemning the recent
Japanese occupation of Manchuria he seemed to look ahead to a far future:
“e discoveries of scientists,” he wrote, “have given weapons to mankind
which may destroy our present civilization if we do not succeed in avoiding
further wars.
”801 He probably meant military aircra; the horrors of strategic
bombing and even its potential for deterrence through a balance of terror
were much bruited at mid-decade.
But almost certainly he was also thinking
of atomic bombs.
Several weeks earlier, looking for a patron, he had sent Sir Hugo Hirst, the
founder of the British General Electric Company, a copy of the first chapter
of e World Set Free.
“Of course,” he wrote Sir Hugo with a touch of
bitterness, still brooding on Rutherford’s prediction, “all this is moonshine,
but I have reason to believe that in so far as the industrial applications of the
present discoveries in physics are concerned, the forecast of the writers may
prove to be more accurate than the forecast of the scientists.
e physicists
have conclusive arguments as to why we cannot create at present new
sources of energy for industrial purposes; I am not so sure whether they do
not miss the point.
”802
at Szilard saw beyond “energy for industrial purposes” to the possibility
of weapons of war is evident in his next patent amendments, dated June 28
and July 4, 1934.
Previously he had described “the transmutation of
chemical elements”; now he added “the liberation of nuclear energy for
power production and other purposes through nuclear transmutation.” He
proposed for the first time “a chain reaction in which particles which carry
no positive charge and the mass of which is approximately equal to the
proton mass or a multiple thereof [i.e., neutrons] form the links of the
chain.” 803 He described the essential features of what came to be known as a
“critical mass”—the volume of a chain-reacting substance necessary to make
the chain reaction self-sustaining.804 He saw that the critical mass could be
reduced by surrounding a sphere of chain-reacting substance with “some
cheap heavy material, for instance lead,” that would reflect neutrons back
into the sphere, the basic concept for what came to be known (by analogy
with the mud tamped into drill holes to confine conventional explosives) as
“tamper.” And he understood what would happen if he assembled a critical
mass, spelling out the results simply on the fourth page of his application:805
If the thickness is larger than the critical value...
I can produce an
explosion.
As if to mark in some distant inhuman ledger the end of one age and the
beginning of another, Marie Sklodowska Curie, born in Warsaw, Poland, on
November 7, 1867, died that day of Szilard’s filing, July 4, 1934, in Savoy.
Einstein’s was the best eulogy: “Marie Curie is,” he said, “of all celebrated
beings, the only one whom fame has not corrupted.” 806
ere is nothing in the documentary record to indicate that Szilard was
yet thinking of uranium.
His June amendment describes a possible chain
reaction using light, silvery beryllium, element number 4 on the periodic
table.
To study that metal Szilard needed access to a laboratory and a source of
radiation.
e beryllium nucleus was so lightly bound he suspected he could
knock neutrons out of it not only with alpha particles or neutrons but even
with gamma rays or high-energy X rays.
Radium emitted gamma rays and
radium was available conveniently at the nearest large hospital.
So Szilard,
an unusually practical visionary, dropped in to see the director of the
physics department at the medical college of St.
Bartholomew’s Hospital.
Couldn’t he use St.
Bart’s radium, “which was not much in use in
summertime,” for experiments?
Something of value to medicine might
emerge.
807 e director thought he could if he teamed up with someone on
the staff.
“ere was a very nice young Englishman, Mr.
[T.
A.] Chalmers,
who was game, and so we teamed up and for the next two months we did
experiments.”
eir first experiment demonstrated a brilliantly simple method for
separating isotopes of iodine by bombarding an iodine compound with
neutrons.
ey then used this Szilard-Chalmers effect (as it came to be
called), which was extremely sensitive, as a tool for measuring the
production of neutrons in their second experiment: knocking neutrons out
of beryllium using the gamma radiation from radium.
“ese experiments,”
Szilard reminisces wryly, “established me as a nuclear physicist, not in the
eyes of Cambridge, but in the eyes of Oxford.
[Szilard had in fact applied to
Rutherford that spring to work at the Cavendish and Rutherford had turned
him down.] I had never done work in nuclear physics before, but Oxford
considered me an expert....
Cambridge...
would never had made that
mistake.
For them I was just an upstart who might make all sorts of
observations, but these observations could not be regarded as discoveries
until they had been repeated at Cambridge and confirmed.” 808, 809
If Szilard’s summer work helped establish his Oxford reputation, it was
also a personal disappointment: beryllium proved an unsatisfactory
candidate for chain reaction.
e problem, not settled until 1935, lay with
the established mass of helium.
810 e one stable isotope of beryllium
consists of two helium nuclei lightly bound by a neutron.
Its apparently high
mass, which was calculated from Francis Aston’s measurements of the mass
of helium, seemed to indicate that it should be unstable.
But the mass
spectrograph was a skittish instrument even in the hands of its inventor, and
as Bethe, Rutherford and others were about to demonstrate, Aston’s
measurements were inaccurate: he had set the mass of helium too high.
One
casualty of that error was beryllium’s candidacy for chain reaction, for
nuclear power and atomic bombs.
* * *
Emilio Segrè and Edoardo Amaldi pilgrimaged to Cambridge early in July,
short on English but carrying with them a comprehensive report on the
Rome neutron-bombardment investigations.
811 ey met Chadwick,
Kapitza and the other regulars at the Cavendish; observed the retired J.
J.
omson making his rounds; noted Aston, says Amaldi innocently, “going
on improving the accuracy of his measurements of atomic masses”; and had
a memorable meeting with Rutherford, whose “strong personality
dominated the whole laboratory.”
e two young physicists had come to compare experiments with two of
Rutherford’s boys.
An unanswered question hung over the neutron work, a
question that called existing nuclear theory into doubt.812 e Nature paper
they brought with them discussed the difficulty frankly.
It concerned what is
called “radiative capture,” the typical reaction of the heavy elements to
neutron bombardment: a nucleus captures a neutron, emits a photon of
gamma radiation to stabilize itself energetically and thus becomes an isotope
one mass unit heavier.
eory at the time treated the nucleus as if it was one large particle.
As
such, it had a definite diameter, which was modest enough that a speeding
neutron could go in one side and exit out the other in about 10-21 seconds, a
billion times less than a trillionth of a second.
Any capture process would
have to work within that brief interval of time.
Otherwise the neutron would
be gone.
Capturing a neutron means stopping it within a nucleus.
To do that
the nucleus has to absorb the neutron’s energy of motion.
e nucleus in
turn has to get rid of the excess energy.
Which it does: by emitting a gamma
photon.
But the gamma-emission times Fermi’s group had measured were
different from what theory said they ought to be.
e nuclei the Rome group
had studied took at least 10-16 seconds to get around to gamma emission—
one hundred thousand times too long.
And that was unaccountable.
Definite proof of radiative capture would sharpen the challenge to theory.
at required proving beyond doubt, by experiment, that a heavier isotope
really forms when a heavy nucleus captures a neutron.
e Cavendish team
Segrè and Amaldi came to visit in the summer of 1934 accomplished the
first part of the proof, using sodium, while the Italians were on hand.
ey
then returned to Rome and enlisted D’Agostino’s help to perform the
confirming chemistry.
In the heat of Roman August they looked for
additional clear-cut examples and won a double prize: “We also found a
second case of ‘proven’ radiative capture,” Amaldi writes, “which was based
on the discovery of a new radioisotope of [aluminum] with a lifetime of
almost 3 minutes.
”813
Fermi planned to stop off in London for an international physics
conference on his way home from South America.
His young colleagues sent
him word of their aluminum discovery.
He reported to the conference on
the neutron work.
(Szilard also attended, happy to hear praise for his
summer experiments and well launched toward a paying fellowship at
Oxford.) Fermi said his group had studied sixty elements so far and had
induced radioactivity in forty of them.
Discussing the radiative-capture
problem he cited the Cavendish results “and those of Amaldi and Segrè on
aluminium,” which were both, he said, “to be considered particularly
important.” 814, 815 Segrè describes the tempestuous aermath:
Shortly aerwards I caught a cold and could not go to the laboratory for
several days.
Amaldi tried to repeat our experiments and found a different
[half-life] for irradiated aluminum which showed that our so-called (n,γ)
reaction [i.e., neutron in, gamma photon out] did not occur.
is was
hurriedly relayed to Fermi who resented having communicated a result
which now looked to be in error.
He strongly criticized us and did not
conceal his displeasure.
e whole business was becoming very
troublesome because we could not find any fault with the various
experiments which gave inconsistent results.
816
e chastened junior members had their work cut out for them.
A new
recruit joined them, a tall, broad-shouldered, handsome tennis champion
from Pisa named Bruno Pontecorvo, as they set about polishing their first
rough work.
Neutron bombardment activated some elements more intensely
than others.
ey had previously categorized that activation only generally
as strong, medium or weak.
Now they proposed to establish a quantitative
scale of activibility.
ey needed some standard intensity against which to
measure the intensity of other activations.
ey chose the convenient 2.3 -
minute half-life period that neutron bombardment induced in silver.
Amaldi and Pontecorvo got the assignment.
ey immediately found, to
their surprise, that their silver cylinders activated differently in different
parts of the laboratory.
“In particular,” writes Amaldi, “there were certain
wooden tables near a spectroscope in a dark room which had miraculous
properties, since silver irradiated on those tables gained much more activity
than when it was irradiated on a marble table in the same room.
”817
at was a mystery worth exploring.
On October 18 they started a
systematic investigation, a series of measurements made inside and outside a
lead housing.
By October 22 they were prepared to measure what might
happen when only a lead wedge separated the neutron source from its
target.
But the experimenters had to give student examinations that morning
and Fermi decided to go ahead on his own.
He described the historic
moment late in life to a colleague curious about the process of discovery in
physics:
I will tell you how I came to make the discovery which I suppose is the
most important one I have made.
We were working very hard on the
neutron-induced radioactivity and the results we were obtaining made no
sense.
One day, as I came into the laboratory, it occurred to me that I
should examine the effect of placing a piece of lead before the incident
neutrons.
Instead of my usual custom, I took great pains to have the piece
of lead precisely machined.
I was clearly dissatisfied with something: I
tried every excuse to postpone putting the piece of lead in its place.
When
finally, with some reluctance, I was going to put it in its place, I said to
myself: “No, I do not want this piece of lead here; what I want is a piece of
paraffin.” It was just like that with no advance warning, no conscious prior
reasoning.
I immediately took some odd piece of paraffin and placed it
where the piece of lead was to have been.
818
e extraordinary result of substituting paraffin wax for a heavy element
like lead was a dramatic increase in the intensity of the activation.
“About
noon,” Segrè remembers, “everybody was summoned to watch the
miraculous effects of the filtration by paraffin.
At first I thought a counter
had gone wrong, because such strong activities had not appeared before, but
it was immediately demonstrated that the strong activation resulted from
the filtering by the paraffin of the radiation that produced the
radioactivity.” 819 Laura Fermi says “the halls of the physics building
resounded with loud exclamations: ‘Fantastic!
Incredible!
Black magic!’ ” 820
Not even his most important discovery kept Fermi from going home for
lunch.
He was alone; his wife and daughter would not return from a visit to
the country until the following morning.
He pondered in solitude and may
have considered the difference between wood and marble tables as well as
between paraffin and lead.
When he returned in midaernoon he proposed
an answer: the neutrons were colliding with the hydrogen nuclei in the
paraffin and the wood.
at slowed them down.
Everyone had assumed that
faster neutrons were better for nuclear bombardment because faster protons
and alpha particles always had been better.
But the analogy ignored the
neutron’s distinctive neutrality.
A charged particle needed energy to push
through the nucleus’ electrical barrier.
A neutron did not.
Slowing down a
neutron gave it more time in the vicinity of the nucleus, and that gave it
more time to be captured.
e simple way to test Fermi’s theory was to try some other material
besides paraffin that contained hydrogen (other light nuclei would also work
to slow neutrons down, but hydrogen would work best: its nuclei are
protons, about the same size and mass as neutrons, and they therefore
bounce hardest and soak up the most energy per collision).
Down to the
first floor and out the back door they marched with their silver cylinder and
their neutron source extended in its long glass tube, to the pond in Corbino’s
garden where Rasetti had experimented with raising salamanders, where
they had all caught the fad one summer of sailing candle-powered toy boats,
where the dark, curving leaves and leathery gray drupes of an almond tree
shaded the lively goldfish.
e hydrogen in water (and in goldfish) worked as well as paraffin.821
Back in the lab they quickly tested whatever they could lay hands on to
irradiate: silicon, zinc, phosphorus, which did not seem to be affected by the
slow neutrons; copper, iodine, aluminum, which did.
ey tried radon
without beryllium to make sure the paraffin was affecting neutrons and not
gamma rays.
ey replaced the paraffin with an oxygen compound and
found much less increase in induced radioactivity.
ey went home to dinner but met aerward at Amaldi’s, whose wife had
a typewriter, to prepare a first report.
“Fermi dictated while I wrote,” Segrè
remembers.
“He stood by me; Rasetti, Amaldi, and Pontecorvo paced the
room excitedly, all making comments at the same time.” 822 Laura Fermi
recreates the scene: “ey shouted their suggestions so loudly, they argued
so heatedly about what to say and how to say it, they paced the floor in such
audible agitation, they le the Amaldis’ house in such a state, that the
Amaldis’ maid timidly inquired whether the guests had all been drunk.
”823
Ginestra Amaldi delivered the typed paper, “Influence of hydrogenous
substances on the radioactivity produced by neutrons—I,” to the director of
the Ricerca Scientifica the next morning.824 Tucked away in its historic
paragraphs was a quiet justification for the confusion over aluminum: “e
case of aluminum is noteworthy.
In water it acquires an activity showing a
period slightly shorter than 3 minutes....
is activity under normal
conditions is so weak that it almost disappears compared to other activities
generated in the same element.
”825
Amaldi and Segrè had not been wrong about aluminum.
ey had simply
irradiated different samples of the element on different tables.
e hydrogen
in the wooden table had slowed down some of the neutrons and enhanced
the almost-three-minute activity.
As Hans Bethe once noted wittily, the
efficiency of slow neutrons “might never have been discovered if Italy were
not rich in marble....
A marble table gave different results from a wooden
table.826 If it had been done [in America], it all would have been done on a
wooden table and people would never have found out.”
e discovery of slow-neutron radioactivity meant that Fermi’s group had
to work its way through the elements again looking for different and
enhanced half-lives—which is to say, different isotopes and decay products.
While that work proceeded a paper appeared in the Physical Review
criticizing the group’s earlier study of uranium.
827 e paper’s primary
author was Aristide von Grosse, who had been one of Otto Hahn’s assistants
at the KWI and who had purified the first substantial sample of
protactinium, the element Hahn and Meitner had discovered in 1917.
Von
Grosse argued that when Fermi irradiated uranium he had created
protactinium, atomic number 91, not a new transuranic element.
e Rome
group took the paper as a challenge to further experiment.
At the same time
Hahn and Meitner decided proprietarily to repeat Fermi’s previous uranium
work.
“It was a logical decision,” Hahn explains in his scientific
autobiography; “having been the discoverers of protactinium, we knew its
chemical characteristics.
”828 e increasing number of different half-lives
that investigators in Berlin and Paris found when they irradiated uranium
were puzzling; Hahn correctly felt that he was better qualified than anyone
else in the world to accomplish the subtle radiochemistry necessary to sort
everything out.
In January and February 1935, in the midst of other projects, Amaldi set
to work looking for alpha-emitting reactions in uranium in addition to the
beta reactions the group had originally found.
If uranium emitted alpha
particles when it captured neutrons it would be transmuting down the
periodic table rather than up, which might indeed produce protactinium
along the way.
Amaldi chose to use an ionization chamber connected to a
linear amplifier to capture and measure the radiation.
“I began to irradiate
some foil[s] of uranium,” he writes, “...
and put them immediately aer
irradiation in front of the thin-window ionization chamber.
”829 Nothing
happened.
Conceivably the half-lives were too brief for the run down the
hall from the irradiation area to the ionization chamber.
Amaldi decided to
try irradiating his samples directly in front of the chamber.
at required
screening out unwanted radiation.
e gamma rays from his neutron source,
which would have disturbed the ionization chamber, he blocked by setting a
piece of lead between the source and the chamber: the desirable neutrons
would find the lead no obstacle.
He also wanted to filter out uranium’s natural alpha background.
To do
that he took advantage of the basic law of radioactivity that shorter half-lives
mean more energetic radiation.
e half-life of natural uranium is about 4.5
billion years; its alphas are proportionately mild, mild enough to be blocked
by a layer of aluminum foil.
On the other hand, if there really were half-lives
in his experiment so short that he had to irradiate directly in front of the
ionization chamber to catch them, their alphas should be energetic enough
to breeze easily through the aluminum and the chamber window and enter
the chamber for counting.
So Amaldi wrapped his uranium samples with
aluminum foil.
It did not occur to him that his shielding might also screen
out other reaction products.
In 1935, alpha, beta and gamma radiation were
the only reaction products anyone knew.
“e experiments,” Amaldi
concludes, “gave negative results.” 830 He found no artificially induced alphas
from uranium.
e Italians thought it even more probable then that by irradiating
uranium they were creating new, man-made elements.
Hahn and Meitner
reported they thought so too.
Fermi’s group rounded up its work in the
Proceedings of the Royal Society in a paper Rutherford approvingly passed
along to that journal on February 15:
rough these experiments our hypothesis that the 13-minute and 100-
minute induced activities of uranium are due to transuranic elements
seems to receive further support.
e simplest interpretation consistent
with the known facts is to assume that the 15-second, 13-minute and 100-
minute activities are chain products [i.e., one decays into the next],
probably with atomic number 92, 93 and 94 respectively and atomic
weight 239.831
But the truth was, uranium was a confusion, and no one yet knew.
What else besides beryllium?
Leo Szilard asked himself in London.
Beryllium looked suspicious.
What other elements might chain-react?
He
answered with an amended patent specification on April 9, 1935: “Other
examples for elements from which neutrons can liberate multiple neutrons
are uranium and bromine.
”832 He was guessing, and without research funds
he saw no way to experiment.
e physicists he talked to remained
profoundly skeptical of his ideas.
“So I thought, there is aer all something
called ‘chain reaction’ in chemistry.
It doesn’t resemble a nuclear chain
reaction, but still it’s a chain reaction.
So I thought I would talk to a
chemist.” 833 e chemist he thought he would talk to was someone even
more skillful than Leo Szilard at raising funds: Chaim Weizmann, who now
lived and worked in London.
Weizmann received Szilard and “understood
what I told him.
”834 He asked Szilard how much money he needed.
Szilard
said £2,000—about $10,000.
ough he was certainly hard-pressed for
funding himself, Weizmann said he would see what he could do.
Szilard
recalls:
I didn’t hear from him for several weeks, but then I ran into Michael
Polanyi, who by that time had arrived in Manchester and was head of the
chemistry department there.
Polanyi told me that Weizmann had come to
talk to him about my ideas for the possibility of a chain reaction, and he
wanted Polanyi’s advice on whether he should get me this money.
Polanyi
thought that this experiment should be done.
A decade passed before Szilard and Weizmann met again, a gulf of history.
Weizmann had not neglected Szilard’s request, he explained then in apology
in late 1945; he had only not succeeded in raising the funds.
Since the beginning of his rescue work in England Szilard had been in
occasional contact with the physicist Frederick Alexander Lindemann, who
was professor of experimental philosophy at Oxford and director of the
Clarendon Laboratory there.835 It was Lindemann, wealthy and well-
connected, who was arranging a fellowship for Szilard, part of his
continuing campaign to arm the decrepit Oxford science laboratory against
its splendid Cambridge rival.
Lindemann had made effective use in that
campaign of the Nazi expulsion of the Jewish academics but had given as
good as he got: immediately upon hearing of the civil service law he had
gone to Imperial Chemical Industries and convinced its directors to
establish a grant program, arguing that such an investment would be not
charity but money well spent.
ICI had already begun paying out its first
grant on May 1, 1933, while Beveridge and Szilard were still laying plans.
It
was an ICI grant that Szilard missed winning the following August, perhaps
because he had not yet accomplished his summer of impressive experiment
at St.
Bart’s, but Lindemann was paying attention now.
e tall, handsome Englishman, forty-nine years old in 1935, had been
born in Germany, at Baden-Baden, because his mother chose not to allow
advanced pregnancy to interfere with a visit to that fashionable spa.
To
provide their son with an outstanding education his English parents had
sent him to the Gymnasium in Darmstadt.
As a student before the Great War
at the Darmstadt Technische Hochschule, where he was a protégé of the
physical chemist Walther Nernst (the 1920 chemistry Nobelist), he had
enjoyed such exceptional family connections that he found himself at times
playing tennis with the Kaiser or the Czar.
Inevitably the war made suspect
such golden aernoons.
Lindemann was chagrined and angered in 1915 to
find that the British Army, noting his German birth certificate and German-
sounding name, was unwilling to extend him a commission.
e Army’s decision injured him deeply and may have changed his life.
He
had served as a co-secretary to the 1911 Solvay Conference, standing up
proudly with Nernst, Rutherford, Planck, Einstein, Mme.
Curie, but even
before that youthful apotheosis Nernst had predicted difficulty: “If your
father were not such a rich man,” the blunt German had said, “you would
become a great physicist.” 836 When the Army questioned Lindemann’s
patriotism, writes a refugee colleague, “he became withdrawn to avoid
exposing himself to slights and insults.
Secretiveness about his personal life
developed into a mania and he discouraged personal approaches by a stand-
offishness which was easily mistaken for arrogance.” 837 Lindemann retreated
from original work and became a talented administrator, “the Prof,” an
“unbending Victorian gentleman,” always impeccable in bowler hat, summer
gray suit, winter dark suit, rolled-up umbrella and long, dark coat.
838 If he
could not win a uniform he would adopt one of his own.
He worked for his country during the war at the Royal Aircra Factory at
Farnborough, designing what are now called avionics and doing
aeronautical research.
Tailspins were recognized maneuvers in air fighting
by 1916, a good way to shake off an attacker.
Lindemann was the first to
study them scientifically.
To do so he took flying lessons—only changing
from civilian clothes to flying clothes on the runway beside the plane—then
coolly flew spin aer spin, memorizing his instrument readings as he
plummeted and writing them down aer he had recovered level flight.
Aer the war Lindemann accepted appointment to an Oxford still
donnishly disdainful of science.
He escaped from that further
condescension, says his colleague, into “gracious living,” enjoying weekends
with the nobility that were seldom vouchsafed to less well-born Oxford
dons.
By then a Rolls-Royce was part of his regalia.
In June 1921, on a
weekend at the country estate of the Duke and Duchess of Westminster,
Lindemann met Winston Churchill, twelve years his senior.
“e two men,
so different in background and character, took to each other immediately
and their acquaintance soon turned into a close friendship.” 839 Churchill
recalled that he “saw a great deal of Frederick Lindemann” during the 1930s.
“Lindemann was already an old friend of mine....
We came much closer
from 1932 onwards, and he frequently motored over from Oxford to stay
with me at Chartwell.
Here we had many talks into the small hours of the
morning about the dangers which seemed to be gathering upon us.
Lindemann...
became my chief adviser on the scientific aspects of modern
war.” 840
To this illustrious personage, a vegetarian who daily consumed copious
quantities of olive oil and Port Salut, Szilard turned in the early summer of
1935 to discuss “the question whether or not the liberation of nuclear
energy...
can be achieved in the immediate future.” If “double neutrons”
could be produced, Szilard wrote Lindemann on June 3, “then it is certainly
less bold to expect this achievement in the immediate future than to believe
the opposite.” at meant trouble, Szilard thought, if Germany achieved a
chain reaction first, and he argued for “an attempt, whatever small chance of
success it may have...
to control this development as long as possible.
”841
Secrecy was the way to achieve such control: first, by winning agreement
from the scientists involved to restrict publication, and second, by taking out
patents.
Michael Polanyi had cautioned Szilard late in 1934 that “there is an
opposition to you on account of taking patents.” 842 e British scientific
tradition that opposed patents assumed that those who filed them did so for
mercenary purposes; Szilard explained his patents to Lindemann to clear his
name:
Early in March last year it seemed advisable to envisage the possibility
that...
the release of large amounts of energy...
might be imminent.
Realising to what extent this hinges on the “double neutron,” I have
applied for a patent along these lines....
Obviously it would be misplaced
to consider patents in this field private property and pursue them with a
view to commercial exploitation for private purposes.
When the time is
ripe some suitable body will have to be created to ensure their proper
use.843
For the time being, Szilard proposed to work at Oxford on finding his
“double neutrons,” possibly raising £1,000 on the side “from private persons”
so that he could hire a helper or two.
To bait Lindemann’s Clarendon
ambitions, he argued in conclusion that “this type of work could greatly
accelerate the building up of nuclear physics at Oxford.” 844 As indeed, had it
gone forward, it might have done.
When he learned, possibly from Lindemann, that he could keep his
patents secret only by assigning them to some appropriate agency of the
British government, Szilard offered them first to the War Office.
Director of
Artillery J.
Coombes turned them down on October 8, noting that “there
appears to be no reason to keep the specification secret so far as the War
Department is concerned.” 845 If Lindemann heard of the rejection he must
have remembered his own rejection by the Army in 1915.
e following
February 1936, he intervened on Szilard’s behalf with the Admiralty,
Churchill’s old bailiwick, writing the head of the Department of Scientific
Research and Development cannily:
I daresay you remember my ringing you up about a man working here
who had a patent which he thought ought to be kept secret.
I enclose a
letter from him on the subject as you suggested.
I am naturally somewhat
less optimistic about the prospects than the inventor, but he is a very good
physicist and even if the chances were a hundred to one against it seems
to me it might be worth keeping the thing secret as it is not going to cost
the Government anything.
846
e patent, Szilard explained in the letter Lindemann enclosed, “contains
information which could be used in the construction of explosive bodies...
very many thousand times more powerful than ordinary bombs.” 847 He was
concerned about “the disasters which could be caused by their use on the
part of certain Powers which might attack this country.” Wisely and withal
inexpensively the Admiralty accepted the patent into its safekeeping.
* * *
Eight months in Copenhagen had suited Edward Teller.
He met George
Gamow on the Odessan’s last visit there, aer the Solvay Conference of the
previous autumn; the two of them roared across Denmark and back during
Easter vacation on Gamow’s motorcycle, working over a problem in
quantum mechanics.
e Rockefeller Foundation did not approve of
marriage during a fellowship period, but James Franck had interceded on his
behalf and Teller had married his childhood sweetheart, Mici Harkanyi, in
Budapest on February 26.
He had also written an important paper.
He
returned to London with Mici in the summer of 1934 with his reputation
enhanced and again took up his lectureship at University College.
Assuming
they would settle in England, the Tellers signed a nine-year lease just before
Christmas on a pleasant three-room flat.
Two offers arrived in January, one of which changed Teller’s mind.
e
first was from Princeton: a lectureship.
e second was from Gamow: a full
professorship at George Washington University.
GWU wanted to strengthen
its physics department; Gamow wanted company and liked Teller’s verve.
Teller was twenty-six years old and a newlywed.
He was less than sure
about living in the United States, but a full professorship was not something
he could sensibly refuse.
His wife found someone to sublet the flat.
e U.S.
State Department refused nonquota immigration visas because Teller had
only taught for one year—the Copenhagen time counted merely as a
fellowship—and was required to have taught for two.
He had not, however,
tried for visas on the Hungarian immigration quota because he assumed the
quota was full.
In fact there was room.
e Tellers followed the Gamows
across the Atlantic in August 1935.
* * *
Niels Bohr celebrated his fiieth birthday on October 7.
“Bohr in those days
seemed at the height of his powers, bodily and mentally,” Otto Frisch
observes.
“When he thundered up the steep staircase [of the institute], two
steps at a time, there were few of us younger ones that could keep pace with
him.
e peace of the library was oen broken by a brisk game of pingpong,
and I don’t remember ever beating Bohr at that game.” 848 To honor
Denmark’s leading physicist, George de Hevesy organized a fund-raising
campaign; the Danish people contributed 100,000 kroner to buy Bohr 0.6
gram of radium for his birthday.
De Hevesy divided the radium, in liquid
solution, into six equal parts, mixed each with beryllium powder and
allowed them to dry, making six potent neutron sources.
He had them
mounted on the ends of long rods and stored them in a dry well in the
basement of the institute that had been dug originally to supply vibration-
free housing for a spectrograph.
e institute’s annual Christmas party continued to be held in the well
room, Stefan Rozental recalls: “e lid of the well served as a table, a
Christmas tree stood in the middle, and all the personnel were gathered,
from the chief down to the youngest apprentice in the workshop, and served
a modest meal of sausages and beer.
During the party Niels Bohr used to
make a speech in which he gave a sort of survey of the past year.” 849 Safely
below the sausages, stuck in a gallon flask of carbon disulphide, the neutron
sources silently transmuted sulfur to radioactive phosphorus for de Hevesy’s
biological radioisotope studies.
Bohr had won national distinction for his work and the enduring
gratitude of refugees for his aid; he had also faced personal pain.
In 1932 the
Danish Academy offered him lifetime free occupancy of the Danish House
of Honor, a palatial estate in Pompeiian style built originally for the founder
of Carlsberg Breweries and subsequently reserved for Denmark’s most
distinguished citizen (Knud Rasmussen, the polar explorer, was its previous
occupant).
By then the institute buildings included a modest director’s
house, but the Bohrs shared it with five handsome sons.
ey moved to the
mansion beside the brewery, the best address in Denmark aer the King’s.
Two years later an accident took the Bohrs’ eldest son, Christian, nineteen
years old.
Father, son and two friends were sailing on the Öresund, the sea
passage between Denmark and Sweden, when a squall blew up.
Christian
“was drowned by falling over[board] in a very rough sea from a sloop,”
Robert Oppenheimer reports, “and Bohr circled as long as there was light,
looking for him.
”850 But the Öresund is cold.
For a time Bohr retreated into
grief.
Exhausting as it was, the refugee turmoil helped him.
Everyone at the institute followed Fermi’s neutron work with fascination.
Frisch, the only physicist on hand who knew Italian, was draed to translate
the successive papers aloud as soon as each issue of the Ricerca Scientifica
arrived.
e Copenhagen group was puzzled that slow neutrons affected
some elements more intensely than others; on the one-particle model of the
nucleus even a slow neutron should almost always shoot completely through
a nucleus without capture.
From Cornell Hans Bethe published a paper calculating the slim odds of
neutron capture.
ey conflicted squarely with observation.
Frisch
remembers the colloquium in Copenhagen in 1935 when someone reported
on Bethe’s paper:
On that occasion Bohr kept interrupting, and I was beginning to wonder,
with some irritation, why he didn’t let the speaker finish.
en, in the
middle of a sentence, Bohr suddenly stopped and sat down, his face
completely dead.
We looked at him for several seconds, getting anxious.
Had he been taken unwell?
But then he suddenly got up and said with an
apologetic smile, “Now I understand it.” 851
What Bohr understood about the nucleus he embodied in a landmark
lecture to the Danish Academy on January 27, 1936, subsequently published
in Nature.
“Neutron capture and nuclear constitution” exploited the
phenomenon of neutron capture to propose a new model of the nucleus;
once again, as he had with Rutherford’s planetary model of the atom, Bohr
stood on the solid ground of experiment to argue for radical theoretical
change.852
He visualized a nucleus made up of neutrons and protons closely packed
together—a model now familiar—rather than a single particle.
(Nuclear
particles collectively are known as nucleons.) A neutron entering such a
crowded nucleus would not pass through; it would collide with the nearest
nucleons, surrender its kinetic energy (as a cue ball does at break in
billiards) and be captured by the strong force that holds the nucleus
together.
e energy added by the neutron would agitate the nearby
nucleons; they would collide in turn with other nucleons beyond; the net
effect would be a more generally agitated, “hotter” nucleus but one where no
single component could quickly acquire enough energy to push through the
electrical barrier and escape.
If the nucleus then radiated its excess energy by
ejecting a gamma photon, “cooling off,” none of its nucleons could accrue
enough energy to escape.
e result, already confirmed by Fermi’s
experiments, would be the creation of a heavier isotope of the original
element being bombarded.
More violent assaults on the nucleus, Bohr thought, would still disperse
their energies throughout the compound nucleus created by their capture.
Subsequent reconcentration of the energy might allow the nucleus to eject
several charged or uncharged particles.
Bohr did not think his compound
model of the nucleus boded well for harnessing nuclear energy:
For still more violent impacts, with particles of energies of about a
thousand million volts, we must even be prepared for the collision to lead
to an explosion of the whole nucleus.
Not only are such energies, of
course, at present far beyond the reach of experiments, but it does not
need to be stressed that such effects would scarcely bring us any nearer to
the solution of the much discussed problem of releasing the nuclear
energy for practical purposes.
Indeed, the more our knowledge of nuclear
reactions advances the remoter this goal seems to become.853
us by the mid-1930s the three most original living physicists had each
spoken to the question of harnessing nuclear energy.
Rutherford had
dismissed it as moonshine; Einstein had compared it to shooting in the dark
at scarce birds; Bohr thought it remote in direct proportion to
understanding.
If they seem less perceptive in their skepticism than Szilard,
they also had a better grasp of the odds.
e essential future is always
unforeseen.
ey were experienced enough not to long for it.
In his lecture Bohr preferred to state only general principles, but to trace
“the consequences of the general argument here developed” he had a specific
mathematical model in mind.
854 He published a discussion of that model
the following year, in 1937.
It reached all the way back to his doctoral
dissertation on the surface tension of fluids to demonstrate the usefulness of
treating the atomic nucleus as if it were a liquid drop.
1
e tendency of molecules to stick together gives liquids a “skin” of
surface tension.
A falling raindrop thus rounds itself into a small perfect
sphere.
But any force acting on a liquid drop deforms it (think of the
wobbles of a water-filled balloon thrown into the air and caught).
Surface
tension and deforming forces work against each other in complex ways; the
molecules of the liquid bump and collide; the drop wobbles and distorts.
Eventually the added energy dissipates as heat, and the drop steadies again.
e nucleus, Bohr proposed, was similar.
e force that stuck the
nucleons together was the nuclear strong force.
Counteracting that strong
force was the common electrical repulsion of the positively charged nuclear
protons.
e delicate balance between the two fundamental forces made the
nucleus liquidlike.
Energy added from the outside by particle bombardment
deformed it; it wobbled like a liquid drop, oscillating complexly just as the
braided streams of water Bohr had studied for his dissertation had
oscillated.
Which meant he could use Rayleigh’s classical formulae for the
surface tension of liquids to understand the complex nuclear energy levels
and exchanges that Fermi’s work had revealed.
“is 1937 paper had to close
with many issues not cleared up,” writes the American theoretical physicist
John Archibald Wheeler, who helped Bohr clear up more of them later.
855,
856 e liquid-drop model proved useful, however, and Frisch in
Copenhagen and Meitner in Berlin, among others, took it to heart.
* * *
One fine October ursday in 1937 Ernest Rutherford, a vigorous sixty-six,
went out into the garden of his house on the green Cambridge Backs to trim
a tree.
He took a bad fall.
He was “seedy” later in the day, Mary Rutherford
said—nausea and indigestion—and she arranged for a masseur.
857
Rutherford vomited that night.
In the morning he called his family doctor.
He suffered from a slight umbilical hernia, which he confined with a truss;
his doctor found a possible strangulation, consulted with a specialist and
directed the Rutherfords to the Evelyn Nursing Home for emergency
surgery.
Rutherford told his wife along the way that his business and
financial affairs were all in order.
She said his illness wasn’t serious and asked
him not to worry.
Surgery that evening confirmed a partial strangulation, released the
imprisoned portion of the small intestine and restored its circulation.
Saturday Rutherford seemed to be recovering but he began vomiting again
on Sunday and there were signs of infection, deadly in those days before
antibiotics.
Monday he was worse; his doctors consulted the surgeon, a
Melbourne man, who advised against a second operation given the patient’s
age and symptoms.
Rutherford was made comfortable with intravenous
saline, six pints by Tuesday, and a stomach tube.
Tuesday morning, October
19, he was slightly improved, but though his wife judged him “a wonderful
patient [who] bears his discomforts splendidly” and believed she discovered
“just a thread of hope,” he began that aernoon to weaken.858 A bequest he
decided late in the day suggests he found gratitude in those last hours
reviewing his life.
“I want to leave a hundred pounds to Nelson College,” he
told Mary Rutherford.859 “You can see to it.” And again loudly a little later:
“Remember, a hundred to Nelson College.” He died that evening.
“Heart and
circulation failed” because of massive infection, his doctor wrote, “and the
end came peacefully.”
An international gathering of physicists in Bologna that week celebrated
the 200th anniversary of the birth of Luigi Galvani; Cambridge cabled the
news of Rutherford’s death on the morning of October 20.
Bohr was on
hand and accepted the grim duty of announcement.
“When the meeting
scheduled for that morning assembled,” writes Mark Oliphant, “Bohr went
to the front, and with faltering voice and tears in his eyes informed the
gathering of what had happened.
”860 ey were shocked at the abruptness of
the loss.
Bohr had visited Rutherford at Cambridge a few weeks earlier; the
Cavendish men had seen their leader in fine fettle only days ago.
Bohr “spoke from the heart,” says Oliphant, recalling “the debt which
science owed so great a man whom he was privileged to call both his master
and his friend.” For Oliphant it was “one of the most moving experiences of
my life.” Remembering Rutherford in a letter to Oppenheimer on December
20 Bohr balanced loss with hope, complementarily: “Life is poorer without
him; but still every thought about him will be a lasting encouragement.
”861
And in 1958, in a memorial lecture, Bohr said simply that “to me he had
almost been as a second father.
”862
e sub-dean of Westminster immediately approved interment of
Rutherford’s ashes in the nave of Westminster Abbey, just west of Newton’s
tomb and in line with Kelvin’s.
Eulogizing Rutherford at a conference in
Calcutta the following January, James Jeans identified his place in the history
of science:
Voltaire said once that Newton was more fortunate than any other
scientist could ever be, since it could fall to only one man to discover the
laws which governed the universe.
Had he lived in a later age, he might
have said something similar of Rutherford and the realm of the infinitely
small; for Rutherford was the Newton of atomic physics.863
Ernest Rutherford unknowingly wrote his own more characteristic
epitaph in a letter to A.
S.
Eve from his country cottage on the first day of
that last October.
He reported of his garden what he had also done for
physics, vigorous and generous work: “I have made a still further clearance
of the blackberry patch and the view is now quite attractive.
”864
* * *
In September 1934, in the wake of Fermi’s June Nature article “Possible
production of elements of atomic number higher than 92,” a curious paper
appeared in a publication seldom read by physicists, the Zeitschri für
Angewandte Chemie—the Journal of Applied Chemistry.
Its author was a
respected German chemist, Ida Noddack, co-discoverer with her husband
(in 1925) of the hard, platinum-white metallic element rhenium, atomic
number 75.
e paper was titled simply “On element 93” and it severely
criticized Fermi’s work.865 His “method of proof” was “not valid,” Noddack
wrote bluntly.
He had demonstrated that “his new beta emitter” was not
protactinium and then distinguished it from several other elements
descending down the periodic table to lead, but it was “not clear why he
chose to stop at lead.” e old view that the radioactive elements form a
continuous series beginning at uranium and ending at lead, wrote Noddack,
was exactly what the Joliot-Curies’ discovery of artificial radioactivity had
disproved.
“Fermi therefore ought to have compared his new radioelement
with all known elements.”
e fact was, Noddack went on, any number of elements could be
precipitated out of uranium nitrate with manganese.
Instead of assuming the
production of a new transuranic element, “one could assume equally well
that when neutrons are used to produce nuclear disintegrations, some
distinctly new nuclear reactions take place which have not been observed
previously.” In the past, elements have transmuted only into their near
neighbors.
But “when heavy nuclei are bombarded by neutrons, it is
conceivable that the nucleus breaks up into several large fragments, which
would of course be isotopes of known elements but would not be neighbors.”
ey would be, rather, much lighter elements farther down the periodic
table than lead.
Segrè remembers reading the Noddack paper.866 He knows, because he
asked them, that Hahn in Berlin and Joliot in Paris read it.
It made very little
sense to anyone.
“I think whatever chemists read it,” Frisch reminisces,
“probably thought that this was quite pointless, carping criticism, and the
physicists possibly even more so if they read it, because they would say,
‘What’s the use of criticizing unless you give some reason why that criticism
would be valid?’ Nobody had ever found a nuclear disintegration creating
far-removed elements.
”867 Which was a point Noddack had carefully
addressed, but was clearly one reason for the paper’s neglect.
e summary
report for Nature on artificial radioactivity that Amaldi and Segrè had
delivered to Rutherford in midsummer 1934 makes the assumption explicit:
“It is reasonable to assume that the atomic number of the active element
should be close to the atomic number...
of the bombarded element.” 868
But Fermi seldom le anything to assumption, however reasonable.
He
would certainly not have le to assumption this issue, about which he was
already acutely sensitive because of Corbino’s ill-timed speech (Noddack
rubbed salt into that wound by referring to “the reports found in the
newspapers”).
He sat down and performed the necessary calculations.
He
later told at least Teller, Segrè and his American protégé Leona Woods that
he had done so.
869 Teller is quite sure he knows what those calculations
were:
Fermi refused to believe [Noddack]....870 He knew how to calculate
whether or not uranium could break in two....
He performed the
calculation Mrs.
Noddack suggested, and found that the probability was
extraordinarily low.
He concluded that Mrs.
Noddack’s suggestion could
not possibly be correct.
So he forgot about it.
His theory was right...
but...
it was based on the...
wrong experimental information.
Here Teller indicts Aston’s measurement of the mass of helium (the same
that had misled Szilard to beryllium), which “introduced a systematic error
into calculating the mass and energy of nuclei.”
Segrè finds Teller’s version of the story possible but not persuasive.
e
helium mass number problem would not necessarily have ruled out
breaking up the uranium nucleus.
“You know, occasionally Fermi would tell
you things, then you asked him, ‘But really, how?
Show me.’ And then he
would say, ‘Oh, well, I know this on c.i.f’ He spoke Italian.871 ‘C.i.f.
’ meant
‘con intuito formidable,’ ‘with formidable intuition.’ So how he did it, I don’t
know.
On the other hand, Fermi made a lot of calculations which he kept to
himself.”
Leona Woods’ version sheds light on Teller’s:
Why was Dr.
Noddack’s suggestion ignored?
e reason is that she was
ahead of her time.
Bohr’s liquid-drop model of the nucleus had not yet
been formulated, and so there was at hand no accepted way to calculate
whether breaking up into several large fragments was energetically
allowed.
872
If Noddack’s physics was avant garde, her chemistry was sound.
By 1938
her article was gathering dust on back shelves, but Bohr had promulgated
the liquid-drop model of the nucleus and the confused chemistry of
uranium increasingly preoccupied Lise Meitner and Otto Hahn.
9
An Extensive Burst
“I believe all young people think about how they would like their lives to
develop,” Lise Meitner wrote in old age, looking back; “when I did so I
always arrived at the conclusion that life need not be easy provided only that
it was not empty.
And this wish I have been granted.” 873 Sixty years old in
1938, the Austrian physicist had earned wide respect by hard and careful
work.
When Wolfgang Pauli had wished to propose an elusive, almost
massless neutral particle to explain the energy that seemed to disappear in
beta decay—it came to be called the neutrino—he had made his proposal in
a letter to Lise Meitner and Hans Geiger.
James Chadwick was “quite
convinced that she would have discovered the neutron if it had been firmly
in her mind, if she had had the advantage of, say, living in the Cavendish for
years, as I had done.” 874 “Slight in figure and shy by nature,” as her nephew
Otto Frisch describes her, she was nevertheless formidable.875
During the Great War she had volunteered as an X-ray technician with the
Austrian Army; “there,” says Frisch, “she had to cope with streams of injured
Polish soldiers, not understanding their language, and with her medical
bosses who interfered with her work, not understanding X-rays.” 876 She
arranged her leaves from duty to coincide with Otto Hahn’s and hurried to
the Kaiser Wilhelm Institute for Chemistry in Dahlem to work with him;
that was when they identified the element next down from uranium that
they named protactinium.
Aer the war she did physics separately until
1934, when, challenged by Fermi’s work, she “persuaded Otto Hahn to
renew our direct collaboration” to explore the consequences of bombarding
uranium with neutrons.877 Meitner headed the physics department at the
institute then, of which Hahn had become the director.
She had attained by
middle age, Hahn remarks fondly, “not only the dignity of a German
professor, but also one of his proverbial attributes, absentmindedness.” At a
scientific gathering “a male colleague greeted her by saying, ‘We met on an
earlier occasion.’ Not remembering that earlier occasion, she replied in all
seriousness, ‘You probably mistake me for Professor Hahn.’ ”878 Hahn supposed she was thinking of the many papers they had published together.
If she hid her shyness behind formidable reserve, among friends, Frisch
says, “she could be lively and cheerful, and an excellent storyteller.
”879 Her
nephew thought her “totally lacking in vanity.” 880 She wore her thick dark
hair, now graying, pulled back and coiled in a bun and her youthful beauty
had muted to bright but darkly circled eyes, a thin mouth, a prominent nose.
She ate lightly but drank quantities of strong coffee.
Music moved her; she
followed it as other people follow trends and fashions in art (a family
cultivation—her sister, Frisch’s mother, was a concert pianist).
She made a
duet at the piano on visits with her musical nephew, “though hardly
anybody else knew that she could play.
”881 She lived in an apartment at the
KWI and when there was time she took long walks, ten miles or more a day:
“It keeps me young and alert.” 882 Her most holy commitment, Frisch
thought, “the vision she never lost” that filled her life, was “of physics as a
battle for final truth.” 883
e truth she battled for through the later 1930s was hidden somewhere
in the complexities of uranium.
She and Hahn, and beginning in 1935 a
young German chemist named Fritz Strassmann, worked to sort out all the
substances into which the heaviest of natural elements transmuted under
neutron bombardment.
By early 1938 they had identified no fewer than ten
different half-life activities, many more than Fermi had demonstrated in his
first pioneering survey.
ey assumed the substances must be either isotopes
of uranium or transuranics.
“For Hahn,” says Frisch, “it was like the old days
when new elements fell like apples when you shook the tree; [but] Lise
Meitner found [the energetic reactions necessary to produce such new
elements] unexpected and increasingly hard to explain.
”884
Meanwhile Irene Curie had begun looking into uranium with a visiting
Yugoslav, Pavel Savitch.
ey described a 3.5 -hour activity the Germans had
not reported and suggested it might be thorium, element 90, with which
Curie had years of experience.
If true, the Curie-Savitch suggestion would
mean that a slow neutron somehow acquired the energy to knock an
energetic alpha particle out of the uranium nucleus.
e KWI trio scoffed,
looked for the 3.5 -hour activity, failed to find it and wrote the Radium
Institute suggesting a public retraction.
e French team identified the
activity again and discovered they could separate it from their uranium by
carrier chemistry using lanthanum (element 57, a rare earth).
ey
proposed therefore that it must be either actinium, element 89, chemically
similar to lanthanum but even harder than thorium to explain, or else a new
and mysterious element.
Either way, their findings called the KWI work into doubt.
Hahn met
Joliot in May at a chemistry congress in Rome and told the Frenchman
cordially but frankly that he was skeptical of Curie’s discovery and intended
to repeat her experiment and expose her error.
885 By then, as Joliot
undoubtedly knew, his wife had already raised the stakes, had tried to
separate the “actinium” from its lanthanum carrier and had found it would
not separate.
No one imagined the substance could actually be lanthanum:
how could a slow neutron transmute uranium into a much lighter rare earth
thirty-four places down the periodic table?
“It seems,” Curie and Savitch
reported that May in the Comptes Rendus, “that this substance cannot be
anything except a transuranic element, possessing very different properties
from those of other known transuranics, a hypothesis which raises great
difficulties for its interpretation.
”886
In the course of this exotic debate Meitner’s status changed.
Adolf Hitler
bullied the young chancellor of Austria to a meeting at the German
dictator’s Berchtesgaden retreat in Bavaria in mid-February.
“Who knows,”
Hitler threatened him, “perhaps I shall be suddenly overnight in Vienna: like
a spring storm.
”887 On March 14 he was, triumphantly parading; the day
before, with the raw new German Wehrmacht occupying its capital, Austria
had proclaimed itself a province of the ird Reich and its most notorious
native son had wept for joy.
e Anschluss—the annexation—made Meitner
a German citizen to whom all the ugly anti-Semitic laws applied that the
Nazi state had been accumulating since 1933.
“e years of the Hitler
regime...
were naturally very depressing,” she wrote near the end of her life.
“But work was a good friend, and I have oen thought and said how
wonderful it is that by work one may be granted a long respite of
forgetfulness from oppressive political conditions.
”888 Aer the spring storm
of the Anschluss her grant was abruptly withdrawn.
Max von Laue sought her out then.
He had heard that Heinrich Himmler,
head of the Nazi SS and chief of German police, had issued an order
forbidding the emigration of any more academics.
Meitner feared she might
be expelled from the KWI and le unemployed and exposed.
889 She made
contact with Dutch colleagues including Dirk Coster, the physicist who had
worked in Copenhagen with George de Hevesy in 1922 to discover hafnium.
e Dutchmen persuaded their government to admit Meitner to Holland
without a visa on a passport that was nothing more now than a sad souvenir.
Coster traveled to Berlin on Friday, July 16, arriving in the evening, and
went straight to Dahlem to the KWI.
e editor of Naturwissenschaen, Paul
Rosbaud, an old friend, showed up as well, and together with Hahn the men
spent the night helping Meitner pack.
“I gave her a beautiful diamond ring,”
Hahn remembers, “that I had inherited from my mother and which I had
never worn myself but always treasured; I wanted her to be provided for in
an emergency.” 890
Meitner le with Coster by train on Saturday morning.
Nine years later
she remembered the grim passage as if she had traveled alone:
I took a train for Holland on the pretext that I wanted to spend a week’s
vacation.
At the Dutch border, I got the scare of my life when a Nazi
military patrol of five men going through the coaches picked up my
Austrian passport, which had expired long ago.
I got so frightened, my
heart almost stopped beating.
I knew that the Nazis had just declared
open season on Jews, that the hunt was on.
For ten minutes I sat there and
waited, ten minutes that seemed like so many hours.
en one of the Nazi
officials returned and handed me back the passport without a word.
Two
minutes later I descended on Dutch territory, where I was met by some of
my Holland colleagues.
891
She was safe then.
She moved on to Copenhagen for the emotional
renewal of rest at the Carlsberg House of Honor with the Bohrs.
Bohr had
found a place for her in Sweden at the Physical Institute of the Academy of
Sciences on the outskirts of Stockholm, a thriving laboratory directed by
Karl Manne Georg Siegbahn, the 1924 Physics Nobel laureate for work in X-
ray spectroscopy.892 e Nobel Foundation provided a grant.
She traveled to
that far northern exile, to a country where she had neither the language nor
many friends, as if to prison.
* * *
Leo Szilard was looking for a patron.
Frederick Lindemann had arranged an
ICI fellowship for him at Oxford beginning in 1935, and for a while Szilard
worked there, but the possibility of war in Europe made him restless.
From
Oxford in late March 1936 he had written Gertrud Weiss in Vienna that she
should consider emigrating to America; he appears to have applied his
reasoning to his own case as well.
Szilard had met Weiss in his Berlin years
and subsequently advised and quietly courted her.
Now she had graduated
from medical school.
At his invitation she came to Oxford to see him.
ey
walked in the country; she photographed him standing at roadside before a
weathered log barrier, rounding at thirty-eight but not yet rotund, with a
budding young tree filigreed behind him.893 “He told me he would be
surprised if one could work in Vienna in two years.
He said Hitler would be
there.
And he was”—the Anschluss—“almost to the day.” 894
Szilard had written in his letter that England was “a very895 likeable
country, but it would certainly be a lot smarter if you went to America....
In America you would be a free human being and very soon would not even
be a ‘stranger.’ ” (Weiss went, and stayed to become a distinguished expert in
public health and, late in their wandering years, Szilard’s wife.) During the
same period Szilard wrote Michael Polanyi he would “stay in England until
one year before the war, at which time I would shi my residence to New
York City.
”896 e letter provoked comment, Szilard enjoyed recalling; it was
“very funny, because how can anyone say what he will do one year before the
war?” As it turned out, his prognostication was off by only four months: he
arrived in the United States on January 2, 1938.
Before then Szilard had located a possible patron there, a Jewish financier
of Virginia background named Lewis Lichtenstein Strauss, his first and
middle names honoring his East Prussian maternal grandfather, his last
name soened in Southern fashion to straws.897 Forty-two years old in 1938,
Lewis Strauss was a full partner at the New York investment-banking house
of Kuhn, Loeb, a self-made millionaire, an adaptable, clever but thin-
skinned and pompous man.
Strauss had dreamed as a boy of becoming a physicist.
e recession of
1913–14 had staggered his family’s Richmond business—wholesale shoes—
and his father had called on him at seventeen to drum a four-state territory.
He did well; by 1917 he had saved twenty thousand dollars and was once
again preparing to pursue a physics career.
is time the Great War
intervened.
A childhood accident had le Strauss with marginal vision in
one eye.
His mother doted on him.
She allowed his younger brother to
volunteer for military service but looked for some less dangerous
contribution for her favorite son.
It turned up when Woodrow Wilson
appointed the celebrated mining engineer and Belgian relief administrator
Herbert Hoover as Food Administrator to manage U.S.
supplies during the
war.
e wealthy Hoover was serving in Washington without pay and
assembling a prosperous, unpaid young staff, Rhodes scholars preferred.
Rosa Lichtenstein Strauss sent her boy.
He was twenty-one, knew how to ingratiate himself, knew also how to
work.
Improbable as it appears against a field of Rhodes scholars, within a
month Hoover appointed the high-school-graduate wholesale shoe
drummer as his private secretary.
Aer the Armistice young Strauss shied
with Hoover to Paris, hastily picked up French at tutoring sessions over
lunch and helped organize the allocation of 27 million tons of food and
supplies to twenty-three countries.
On the side he assisted the Jewish Joint
Distribution Committee in its work of relieving the suffering of the
hundreds of thousands of Jewish refugees streaming from Eastern Europe in
the wake of war.
Strauss believed God had planned his life, which contributed greatly to his
self-confidence.
God let him take up employment when he was twenty-
three, in 1919, at Kuhn, Loeb, a distinguished house with a number of major
railroads among its clients.
Four years later he married Alice Hanauer,
daughter of one of the partners.
His salary and participation reached
$75,000 a year in 1926; the following year it escalated to $120,000.
In 1929
he became a partner himself and settled into prosperous gentility.
e 1930s brought him pain and grief.
Aer resisting Chaim Weizmann’s
attempts to convert him to Zionism at a Jewish conference in London in
1933—“My boy, you are difficult,” Weizmann told him; “we will have to
grind you down”—he returned to the United States to discover his mother
terminally ill with cancer.
898 She died early in 1935; the disease took his
father as well in the hot summer of 1937.
Strauss looked for a suitable
memorial.
“I became aware,” he reports in his memoirs, “of the inadequate
supply of radium for the treatment of cancer in American hospitals.” 899 He
established the Lewis and Rosa Strauss Memorial Fund and turned up a
young refugee physicist from Berlin, Arno Brasch.
Brasch had designed a
capacitor-driven discharge tube for producing bursts of high-energy X rays,
a “surge generator.” When Leo Szilard was working at St.
Bart’s with
Chalmers in the summer of 1934 he had arranged for Brasch and his
colleagues in Berlin to break up beryllium with hard X rays; the experiment
had been a success and Brasch and four other contributors had signed the
report to Nature along with Chalmers and Szilard.900 If X rays could break
up beryllium they might at least induce radioactivity in other elements.
“An
isotope of cobalt thus produced,” writes Strauss, “would be radioactive and
would emit gamma rays similar to the radiation produced by radium....
Radioactive cobalt could be made...
at a cost of a few dollars a gram.
Radium was then priced at about fiy thousand dollars a gram....
I foresaw
the possibility of producing the isotope in quantity and of giving it to
hospitals as a memorial to my parents.
”901
Enter Leo Szilard, still in England:
August 30, 1937902
Dear Mr.
Strauss:
I understand that you are interested in the development of a surge
generator with the view of using it for producing artificially radioactive
elements....
At present...
I am not in the position of [offering manufacturing rights
under this patent].
It is possible, however, that at a later date...
I shall
obtain full liberty of action concerning this patent.
If this happens I shall
let you have a non-exclusive license, royalty free, but limited to the
production of radioactive elements by means of high voltage generated by
a surge generator.
Yours very truly,
Leo Szilard
Brasch and Szilard owned the patent in question jointly.
903 Szilard’s letter
offers to give his interest away free of charge nonexclusively to Strauss, a
politic salutation to a rich man.
But not even Leo Szilard could live on air,
and as Strauss makes clear in his memoirs, the two young physicists
eventually “asked me to finance them in the construction of a ‘surge
generator.’ ” 904 On the other hand, Szilard as usual seems to have sought no
personal financial gain from the project beyond, perhaps, basic support.
In
the time he could spare from observing the developing disaster in Europe he
was apparently trying to promote the building of equipment with which he
might explore further the possibility of a chain reaction.
He crossed the Atlantic in late September to reconnoiter.
A friend
remembers discussing the feasibility of an atomic bomb with Szilard during
this period.
“In the same conversation he spoke of his ideas for preserving
peaches in tins in such a way that they would retain the texture and taste of
the fresh fruit.
”905 When the surge-generator negotiations bogged down in
debates among the lawyers, the resourceful Szilard distracted Strauss with
the idea of using radiation to preserve and protect the natural products of
farm and field.906 e tobacco worm might be exterminated, for example.
But would irradiation harm the tobacco?
Among Szilard’s surviving papers
is lodged a fading letter from Dr.
M.
Lenz of the Montefiore Hospital for
Chronic Diseases that reports the decisive experiment:
On April 14, 1938, at 2:30 p.m.
907, your six cigars were irradiated with 100
kv., a filter focus distance of 20 cm.
with ten minutes in front and ten
minutes over the back of each cigar.
is gave them 1000 r.
in front and
1500 r.
in back of each cigar.
I hope that your friend finds the taste unchanged.
Szilard also bought pork from a meat market on Amsterdam Avenue,
saving the receipt, and arranged its irradiation to see if X rays might kill the
parasitic worm of trichinosis.
He even dispatched his brother Béla to
Chicago to discuss the matter with Swi & Company, which reported it had
in fact made similar experiments of its own.
e surge-generator project developed through the year, incidentally
giving Strauss the opportunity to meet Ernest Lawrence, who dropped by to
pitch the new sixty-inch cyclotron he was building—the pole pieces were
sixty inches across, but the magnet would weigh nearly two hundred tons.
Lawrence and his brother John, a physician, had arrested their mother’s
cancer with accelerator radiation and intended to use the big cyclotron to
further that research.
Strauss remained loyal to the surge generator.
Segrè encountered Strauss’s Hungarian wizard in New York that summer.
e elegant Italian was professor of physics at Palermo by then, married to a
German woman who had fled Breslau to escape the Nazis, with a young son:
I le Palermo with a return ticket, and I arrived in New York.
908 I met Szilard.
“Oh, what are you doing here?” He was a good friend of mine.
I
knew him quite well.
“What are you doing here?
What’s going on?”
I said, “I’m going to Berkeley to look at the short-lived isotopes of
element 43,” which was my plan.
“I’ll work there the summer, and then I’ll
go back to Palermo.”
He said, “You are not going back to Palermo.
By this fall, God knows
what will happen!
You can’t go back.”
I said, “Well, I have a return ticket.
Let’s hope for the best.”
But I had gotten a passport for my wife and my son before leaving,
because I smelled that the situation was dangerous.
So I took the train in
New York, Grand Central, and I bought the newspaper in Chicago.
I still
remember it.
I will remember it as long as I live.
I opened the newspaper,
and I found out that Mussolini had started the antisemitic campaign and
had fired everybody.
So there I was.
So I had the ticket and went to
Berkeley.
I started to work on my short-lived isotopes of technetium, but
at the same time I tried to get some job.
en I got my wife here.
e pall of racism had dropped over Italy.
* * *
e physicists at the institute on Via Panisperna had been alert to the
darkening Italian prospect since at least the mid-1930s.
Segrè remembers
asking Fermi in the spring of 1935 why the group’s mood seemed less happy.
Fermi suggested he look for an answer on the big table in the center of the
institute reading room.
Segrè did and found a world atlas there.
He picked it
up; it fell open automatically to a map of Ethiopia, which Italy in a show of
Fascist bravado was about to invade.909 By the time the invasion began all
but Amaldi were examining their options.
Fermi went off to the University of Michigan’s summer school in Ann
Arbor, renewing an affiliation he had begun with Laura in the summer of
1930.
He liked America.
“He was attracted,” Segrè notes with an ear for
Fermi’s priorities, “by the well-equipped laboratories, the eagerness he
sensed in the new generation of American physicists, and the cordial
reception he enjoyed in academic circles.
Mechanical proficiency and
practical gadgets in America counterbalanced to an extent the beauty of
Italy.
American political life and political ideals were immeasurably superior
to fascism.” 910 Fermi swam in Michigan’s cool lakes and learned to enjoy
American cooking.
But the pressure of events in Italy was not yet sufficiently
extreme, and Laura, Roman to her fine bones, was more than reluctant to
leave the city of plane trees and classical ruins where she was born.
Nor was
anti-Semitism yet an issue in Italy—Mussolini had even declared he did not
propose to make it one.
ere was less to hold the other men.
Rasetti summered at Columbia
University that year, 1935, and decided to stay on.
Segrè had shied to
Palermo but began looking toward Berkeley.
Pontecorvo moved to Paris.
D’Agostino went to work for the Italian National Research Council.
Amaldi
and Fermi pushed on alone, Amaldi remembers, Fermi even jettisoning his
daily routine for the distraction of experiment:
We worked with incredible stubbornness.
We would begin at eight in the
morning and take measurements [they were examining the
unaccountably differing absorption of neutrons by different elements],
almost without a break, until six or seven in the evening, and oen later.
e measurements...
were repeated every three or four minutes,
according to need, and for hours and hours for as many successive days as
were necessary to reach a conclusion on a particular point.
Having solved
one problem, we immediately attacked another....
“Physics as soma” was
our description of the work we performed while the general situation in
Italy grew more and more bleak, first as a result of the Ethiopian
campaign and then as Italy took part in the Spanish Civil War.911
Fermi taught a summer course in thermodynamics at Columbia
University in 1936 as the civil war began in Spain that would last three years,
claim a million lives and set Mussolini decisively at Hitler’s side.
e
following January Corbino died unexpectedly of pneumonia at sixty-one
and the hostile occupant at the north end of the institute’s second floor,
Antonino Lo Sordo, a good Fascist, was appointed to succeed him.
“at
was a sign that Fermi’s fortunes were declining in Italy,” Segrè notes.912
“America,” he concludes of those depressing years, “looked like the land of
the future, separated by an ocean from the misfortunes, follies, and crimes of
Europe.
”913
If the Anschluss was a test of Hitler’s strength, it was also a test of
Mussolini’s willingness to acquiesce to complicity in crime.
He had posed as
Austria’s protector; on the night of the March 1938 invasion Hitler waited
near hysteria at the Chancellery in Berlin for a response from Rome to a
letter he had sent justifying his action.
e call came at 10:25 P.M.
and the
Führer snatched up the phone.
“I have just come back from the Palazzo
Venezia,” his representative reported.
“e Duce accepted the whole thing in
a very friendly manner.
He sends you his regards....
Mussolini said that
Austria would be immaterial to him.” Hitler replied: “en please tell
Mussolini I will never forget him for this!
Never, never, never, no matter
what happens!...
As soon as the Austrian affair has been settled I shall be
ready to go with him through thick and thin—through anything!” e
Führer visited Rome in triumph in May, parading into districts the Duce
had ordered hastily face-lied to conceal their decay.914 Fermi’s circle
repeated the verse passed around the city by word of mouth by which an
indignant Roman poet greeted the Nazi dictator:
Rome of travertine splendor
Patched with cardboard and plaster
Welcomes the little housepainter
As her next lord and master.
915
Italy would only be saved, Fermi told Segrè bitterly, if Mussolini went crazy
and crawled on all fours.916
e summer of 1938, July 14, brought the anti-Semitic Manifesto della
Razza of which Segrè read in the Chicago newspaper on his way from New
York to Berkeley.
Italians are Aryans, the manifesto claimed.
But “Jews do
not belong to the Italian race.” 917 In Germany the vicious distinction had
been commonplace; in Italy it was shocking.
Italian Jews, only one in a
thousand, were largely assimilated.
e Fermis’ two children—Giulio, a son,
had been born in 1936—might be exempted since they were Catholic, born
of a nominally Catholic father.
But Laura was a Jew.
She was spending the
summer with the children in the Dolomites, the South Tyrol district named
for the magnesian limestone that rings broad basin meadows with the flat,
sharp formations Italians call “shovels.” Enrico came up preoccupied in
August to the meadow of San Martino di Castrozza to break the news.
When Mussolini pushed through the first anti-Semitic laws early in
September the Fermis decided to emigrate as soon as they could arrange
their affairs.
Fermi wrote four American universities and to avoid suspicion
mailed each letter from a different Tyrolese town.
Five schools shot back
invitations.
In confidence he accepted a professorship at Columbia and went
off to Copenhagen to Bohr’s annual gathering of the brethren.
e previous month the International Congress of Anthropological and
Ethnological Sciences had invited Bohr to address it at a special session in
Helsingør, Shakespeare’s Elsinore, on the coast of Zealand north of
Copenhagen.
In the Renaissance castle there Denmark’s most prominent
citizen used the occasion to challenge Nazi racism publicly before the world.
It was a brave statement by a brave man.
Bohr understood that the major
Western democracies were not likely to rally to the defense of his small,
unprotected nation when Hitler eventually turned to look its way.
George
Placzek, a Bohemian theoretician working in Copenhagen whose tongue
was almost as sharp as Pauli’s, had already encapsulated that cruel truth.
“Why should Hitler occupy Denmark?” Placzek quipped to Frisch one day.
“He can just telephone, can’t he?
”918
Against the brutal romanticism of German Blood and Earth, Bohr set the
subtle corrective of complementarity.
He spoke of “the dangers, well known
to humanists, of judging from our own standpoint cultures developed
within other societies.” 919 Complementarity, he proposed, offered a way to
cope with the confusion.
Subject and object interact to obscure each other in
cultural comparisons as in physics and psychology; “we may truly say that
different human cultures are complementary to each other.
Indeed, each
such culture represents a harmonious balance of traditional conventions by
means of which latent possibilities of human life can unfold themselves in a
way which reveals to us new aspects of its unlimited richness and variety.
”920
e German delegates walked out.921 Bohr went on to say that the
common aim of all science was “the gradual removal of prejudices,” a
complementary restorative to the usual pious characterization of science as a
quest for incontrovertible truth.
922 To a greater extent than any other
scientist of the twentieth century Bohr perceived the institution of science to
which he dedicated his life to be a profoundly political force in the world.
e purpose of science, he believed, was to set men free.
Totalitarianism, in
Hannah Arendt’s powerful image, drove toward “destroying all space
between men and pressing men against each other.
”923 It was entirely in character that Bohr, at a time of increasing danger, publicly opposed that
drive with the individualistic and enriching discretions of complementarity.
It was also entirely in character, when Fermi came to Copenhagen, that
Bohr should lead him aside, take hold of his waistcoat button and whisper
the message that his name had been mentioned for the Nobel Prize, a secret
traditionally never foretold.
Did Fermi wish his name withdrawn
temporarily, given the political situation in Italy and the monetary
restrictions, or would he like the selection process to go forward?
Which was
the same as telling Fermi he could have the Prize that year, 1938, if he
wanted it and was welcome to use it to escape a homeland that threatened
now despite the distinction he brought it to tear his wife from citizenship.
924
* * *
Leo Szilard’s Cambridge collaborator Maurice Goldhaber emigrated to the
United States in the late summer of 1938 and took up residence as an
assistant professor of physics at the University of Illinois.
925 Szilard appeared
at Goldhaber’s new apartment in Champaign in September to finish work
they had begun together in England and stayed to follow the Munich crisis,
for which purpose his host went out and bought a radio.
Szilard understood,
as Winston Churchill also understood and told his consituents at the end of
August, that “the whole state of Europe and of the world is moving steadily
towards a climax which cannot long be delayed.” 926 Before deciding between
residency in England or the United States, Szilard said later, “I just thought I
would wait and see.” 927
e Sudetes, the border region of mountainous upli that continues
across Czechoslovakia from the Carpathians to the Erzgebirge, sustained at
that time a German-speaking urban and industrialized population of some
2.3 million, about one-third of the population of western Czechoslovakia,
formerly Bohemia.
Nazi agitation began early in the Sudetenland; by 1935 a
surrogate Nazi organization had become the largest political party in the
Czechoslovakian republic.
Hitler wanted Czechoslovakia next aer Austria
to facilitate his dream of German expansion, Lebensraum, and to deny
airfields and support to the Soviet Union in the war he was well along in
planning.
e Sudetenland was his key.
Czechoslovakia had built
fortifications against German invasion across the Sudetes; aer 1933 it
imposed restrictions on the Sudeten Germans in an effort to protect that
flank from subversion.
Hitler opened his Czechoslovakian campaign even
before the Anschluss, asserting the Reich’s duty to protect the Sudeten
Germans.
rough the summer of 1938 German pressure on
Czechoslovakia increased while the Western democracies maneuvered to
avoid confrontation.
By the time Szilard began listening to Maurice Goldhaber’s new radio the
Czech government had established full martial law in the Sudetenland but
also offered autonomy to the region in excess of what the Sudeten German
Party had demanded.
ese developments prompted the British Prime
Minister, Neville Chamberlain, to propose a meeting with Hitler.
Hitler was
delighted.
He invited the Prime Minister to Berchtesgaden.
e last outcome
he wanted was a Czechoslovakian settlement.
He signaled the Sudeten Nazis
to increase their demands.
Chamberlain heard the extremist proclamation
on the radio on September 16 as he rode out by train from Munich: a call for
immediate annexation to the German Reich.
Back in London on September
17 he recommended the annexation.
Hitler, he said, “was in a fighting
mood.” 928
“e British and French cabinets at this time,” writes Churchill, “presented
a front of two overripe melons crushed together; whereas what was needed
was a gleam of steel.
On one thing they were all agreed: there should be no
consultation with the Czechs.
ese should be confronted with the decision
of their guardians.
e Babes in the Wood had no worse treatment.
”929 e
two governments, citing “conditions essential to security,” decided that
Czechoslovakia should cede to Germany all areas of the country where the
population was more than 50 percent German.
930 France had treaty
obligations to Czechoslovakia but chose not to honor them.
Facing such
isolation, the small republic capitulated on September 21.
e Anglo-French proposals invoked self-determination for the German-
speaking areas they defined.
Hitler had agreed to such self-determination
when he saw Chamberlain on September 16.
Now the Prime Minister met
with the Chancellor again, this time at Bad Godesberg on the Rhine outside
Bonn, near Remagen.
Hitler escalated his demands.
“He told me,”
Chamberlain reported immediately aerward to the House of Commons,
“that he never for one moment supposed that I should be able to come back
and say that the principle [of self-determination] was accepted.” 931 Hitler wanted Czech acquiescence without self-determination by September 28 or
he would invade.
Chamberlain did not believe, however, he informed the
Commons, that Hitler was deliberately deceiving him.
e Nazi leader also
told the Prime Minister “that this was the last of his territorial ambitions in
Europe and that he had no wish to include in the Reich people of other races
than Germans.
”932
e Czechs mobilized a million and a half men.
e French partly
mobilized their army.
e British fleet went active.
At the same time a secret
struggle may have been taking place between Hitler and the German general
staff, which resisted any further plunge toward war.
e result should have
been stalemate, but Chamberlain moved again to concession.
“Appeasement” was at that time a popular and not a pejorative word.
“How horrible, fantastic, incredible it is,” the Prime Minister admonished
the British people by radio on September 27, the night before Hitler’s
deadline, “that we should be digging trenches and trying on gas-masks here
because of a quarrel in a faraway country between people of whom we know
nothing!” He volunteered “to pay even a third visit to Germany.” He was, he
said, “a man of peace to the depths of my soul.
”933 He made the offer of a
visit to Hitler at the same time directly by letter, and the Führer took him up
on it the following aernoon.
Chamberlain, French Premier Edouard
Daladier, Mussolini and Hitler met at Munich on the evening of September
29.
By 2 A.M.
the following morning the four leaders had agreed to Czech
evacuation of the Sudetenland without self-determination within ten days
beginning October 1.
At Chamberlain’s suggestion he and Hitler then met
privately and agreed further to “regard the Agreement signed last night...
as symbolic of the desire of our two peoples never to go to war with one
another again.” 934 Before he le Munich, closeted with Mussolini, the Führer
discussed Italian participation in the eventual invasion of the British Isles.935
Chamberlain flew home.
He read the joint declaration to the crowd
gathered at the airport in welcome.
Back in London he waved the
declaration from an upper window of the Prime Minister’s residence.
“is
is the second time there has come back from Germany to Downing Street
peace with honour,” he told the multitude below.
“I believe it is peace in our
time.” 936
A group of refugee scientists was gathered outside the Clarendon
Laboratory at Oxford the next morning discussing the Munich agreement
when Frederick Lindemann drove up.
937 Churchill had described the
Czechoslovakian partition as amounting to “the complete surrender of the
Western Democracies to the Nazi threat of force.
”938 Lindemann, Churchill’s
intimate adviser, was equally disgusted.
One of the refugees asked him if he
thought Chamberlain had something up his sleeve.
“No,” the Prof snapped,
“something down his pants.”
A cable came along to Lindemann then:
HAVE ON ACCOUNT OF INTERNATIONAL SITUATION WITH GREAT REGRET
POSTPONED MY SAILING FOR AN INDEFINITE PERIOD STOP WOULD BE VERY
GRATEFUL IF YOU COULD CONSIDER ABSENCE AS LEAVE WITHOUT PAY STOP
WRITING STOP PLEASE COMMUNICATE MY SINCERELY FELT GOOD WISHES TO ALL
IN THESE DAYS OF GRAVE DECISIONS939
SZILARD
Szilard and Goldhaber found time during the crisis to write up a series of
experiments with indium that they had started in England in 1937 and that
Goldhaber and an Australian student, R.
D.
Hill, had completed before
leaving for the United States.
Szilard had thought indium might be a
candidate for chain reaction but the results indicated that the radioactivity
in indium of which Szilard had been suspicious was caused by a new type of
reaction process, inelastic neutron scattering without neutron capture or
loss.
Szilard was discouraged.
“As my knowledge of nuclear physics
increased,” he said later, “my faith in the possibility of a chain reaction
gradually decreased.
”940 If other kinds of radiation also induced
radioactivity in indium without producing neutrons, then he would have no
more candidates for neutron multiplication and he would have to give up his
belief in the process he still nicknamed “moonshine.” at final experiment
would be worked by friends at the University of Rochester in upstate New
York, where he would travel in early December.
941
* * *
Otto Hahn opened the September 1938 issue of the Comptes Rendus to a
shock.
Part two of the Curie-Savitch study of the elusive 3.5 -hour activity of
uranium appeared there; amid much conjecture its most challenging
conclusion was: “Taken altogether, the properties of R3.5h are those of
lanthanum, from which it is not possible to separate it except by
fractionation.” 9421
Curie and Savitch believed that their R3.5h activity could be at least partly
separated from lanthanum.
It apparently did not occur to them that what
was crystallizing out of solution might be another activity with a similar
half-life, leaving a 3.5 -hour lanthanum activity behind.
ey still could not
believe—nor could anyone else—that uranium bombardment might
produce an element thirty-five steps away down the periodic table.
A
Canadian radiochemist then visiting Dahlem records their German critic’s
response: “You can readily imagine Hahn’s astonishment....
His reaction
was that it just could not be, and that Curie and Savitch were very muddled
up.” 943
Despite his threat to Joliot in May, Hahn had not yet repeated the Curie-
Savitch work.
Now he passed the Comptes Rendus along to Fritz
Strassmann.944 Strassmann studied the French paper and speculated that the
muddle might have a physical cause—two similar radioactivities mixed
together in the same solution.
He told Hahn.
Hahn laughed; the conclusion
seemed improbable.
On second thought, it was worth examining.
As the
Czechoslovakian crisis broke across Europe the two men bombarded
uranium in peaceful Dahlem.
ey used a lanthanum carrier to precipitate
rare-earth elements such as actinium (if any), a barium carrier to precipitate
alkaline-earth elements such as radium (if any).
(Carrier chemicals made it
possible to separate from the parent solution the few thousand atoms of
daughter substances produced by neutron bombardment.
A chemically
similar daughter substance, traceable by its unique half-life, would lodge in
the spaces of the carrier’s crystals as those regular solids formed from
solution by chemical precipitation and would thus be carried away.
Which
carrier accomplished the carrying gave a clue to the part of the periodic
table to which the unknown daughter substance belonged.
en it became a
matter of further separating the daughter substance from the carrier by
fractional crystallization, following it as before by tracing its characteristic
radioactivity.)
Aer a hard week’s work Hahn and Strassmann succeeded in identifying
no fewer than sixteen different activities.
eir barium separations gave
them their most startling results: three previously unknown isotopes which
they believed to be radium.
ey reported their findings in November in
Naturwissenschaen.
e creation of radium, element 88, from uranium,
they pointed out, “must be due to the emission of two successive alpha
particles.” 945
If the physicists had found it hard to swallow that slow-neutron
bombardment might produce thorium (90) or actinium (89), they found it
even harder to swallow that it might produce radium.
Lise Meitner wrote in
warning from Stockholm suggesting pointedly that the two chemists check
and recheck their results.946 Bohr invited Hahn to Copenhagen to lecture on
the strange findings and tried to concoct a sufficiently crazy explanation:
Bohr was skeptical and asked me if it was not highly improbable....
I had
to reply that there was no other explanation, for our artificial radium
could be separated only with weighable quantities of barium as carrier-
substance.
So apart from the radium only barium was present, and it was
out of the question that it was anything but radium.
Bohr suggested that
these new radium isotopes of ours might perhaps in the end turn out to
be strange transuranic elements.947
Of the sixteen activities they had identified in neutron-bombarded uranium
Hahn and Strassmann therefore now turned their full attention to the three
controversial activities carried out of solution by barium.
* * *
Laura Fermi woke to the telephone early on the morning of November 10.
A
call would be placed from Stockholm, the operator advised her.
Professor
Fermi could expect it that evening at six.
Instantly awake to his wife’s message, Fermi estimated the probability at 90
percent that the call would announce his Nobel Prize.
As always he had
planned conservatively, not counting on the award.
e Fermis had
prepared to leave for the United States from Italy shortly aer the first of the
year.
Ostensibly Fermi was to lecture at Columbia for seven months and
then return.
For stays of longer than six months the United States required
immigrant rather than tourist visas, and because Fermi was an academic he
and his family could be granted such visas outside the Italian quota list.
e
ruse of a lecture series was devised to evade a drastic penalty: citizens
leaving Italy permanently could take only the equivalent of fiy dollars with
them out of the country.
But the plan required circumspection.
e Fermis
could not sell their household goods or entirely empty their savings account
without risking discovery.
So the money from the Nobel Prize would be a
godsend.
In the meantime they invested surreptitiously in what Fermi called “the
refugee’s trousseau.” Laura’s new coat was beaver and they distracted
themselves on the day of the Stockholm call shopping for expensive watches.
Diamonds, which had to be registered, they chose not to risk.
Near six o’clock the phone rang.
It was Ginestra Amaldi wondering if they
had heard.
Everyone had gathered at the Amaldis to wait for the call, she
reported.
e Fermis turned on the six o’clock news.
Laura long
remembered the news:
Hard, emphatic, pitiless, the commentator’s voice read the second set of
racial laws.
e laws issued that day limited the activities and the civil
status of the Jews.
eir children were excluded from public schools.
Jewish teachers were dismissed.
Jewish lawyers, physicians, and other
professionals could practice for Jewish clients only.
Many Jewish firms
were dissolved.
“Aryan” servants were not allowed to work for Jews or to
live in their homes.
Jews were to be deprived of full citizenship rights, and
their passports would be withdrawn.
948
e passports of Jews had already been marked.
Fermi had contrived to
keep his wife’s passport clear.
ey probably heard the news from Germany as well: of a vast pogrom the
previous night— Kristallnacht, the night of glass.
A seventeen-year-old
Polish Jewish student had attempted to assassinate Ernst vom Rath, third
secretary in the German Embassy in Paris, on November 7, in reprisal for
German mistreatment of the student’s parents.
Vom Rath died on November
9 and the assassination served as an excuse for general antiSemitic riot.
Mobs torched synagogues, destroyed businesses and stores, dragged Jewish
families from their homes and beat them in the streets.
At least one hundred
people died.
A volume of plate glass was shattered that night across the
ird Reich equal to half the annual production of its original Belgian
sources.
e SS arrested some thirty thousand Jewish men—“especially rich
ones,” its order had specified—and packed them into the concentration
camps at Buchenwald, Dachau and Sachsenhausen, from which they could
be ransomed only at the price of immediate pauperized emigration.
949
Fermi took the Stockholm call.
e Nobel Prize, undivided, would be
awarded for “your discovery of new radioactive substances belonging to the
entire race of elements and for the discovery you made in the course of this
work of the selective power of slow neutrons.
”950 In security the Fermis
could leave the madness behind.
* * *
Lise Meitner had written Otto Hahn of her worries a few days before the
Fermis arrived.
“Most of the time I feel like a wind-up doll running on
automatic,” she told her old friend, “smiling along happily and empty of real
life.
From that you can judge for yourself how productive my efforts are at
work.
And still in the end I’m thankful for it because it forces me to keep my
thoughts together, which isn’t always easy.” She was sorry Hahn’s
rheumatism had returned and was afraid he wasn’t taking care of himself;
she asked aer Planck and von Laue by their private Hahn-Meitner
nicknames, Max Sr.
and Max Jr.; she greeted Hahn’s wife, Edith, and
wondered what Christmas plans he had for his son.
His uranium work was
“really very interesting.” 951 She hoped he would write again soon.
She was living in a small hotel room—there was hardly space to unpack—
and having trouble sleeping.
People told her she was too thin.
Worse,
conditions at the Physical Institute were not what she had expected them to
be.
952 A Swedish friend, Eva von Bahr-Bergius, a physicist she knew from
Berlin who had been a lecturer at the University of Uppsala, had helped with
arrangements and was gradually breaking the bad news.953 Manne Siegbahn
had not wanted to take Meitner on.
He had no money for her, he had
complained; he could give her a place to work but no more.
Von Bahr-
Bergius had pursued the Nobel Foundation grant.
But it provided nothing
for equipment or assistance.
Meitner blamed herself: “Of course it’s my fault;
I should have prepared much better and much earlier for my leaving, should
at least have had drawings made of the most important apparatus [she
would need].” 954
She was a strong woman, but she was miserable and alone.
Hahn
responded with sympathy.
At midmonth she thanked him for that “dear
letter,” then changed moods and charged him with indifference:
“Concerning myself I sometimes suspect you don’t understand my way of
thinking....
Right now I really don’t know if anyone cares about my affairs
at all or if they will ever be taken care of.” 955
Hahn was pursuing Meitner’s affairs as well as his own.
With her moody
letter at hand he stormed down to the revenue office, which was responsible
for inventorying her furniture and other property before allowing its release,
and laid on what he called “a little seizure of my ‘ecstasy,’ ” aer which “the
matter went somewhat better.” 956, 957 at news he wrote to Meitner on Monday evening, December 19, from the KWI.958 Only then did he report
why he had not yet le the laboratory:959
As much as I can through all of this I am working, and Strassmann is
working untiringly, on the uranium activities....
It’s almost 11 at night;
Strassmann will return at 11:30 so that I can see about going home.
e
fact is, there’s something so strange about the “radium isotopes” that for
the time being we are mentioning it only to you.
e half-lives of the three
isotopes are quite precisely determined; they can be separated from all
elements except barium; all the processes are in tune.
Just one is not—
unless there are extremely unusual coincidences: the fractionation doesn’t
work.
Our radium isotopes act like barium.
Hahn and Strassmann worked in three rooms on the ground floor of the
Kaiser Wilhelm Institute for Chemistry, the building with the Pickelhaube
dome: Hahn’s large personal chemistry laboratory north off the main lobby,
a measurement room across the hall at the near end of the wing that
extended northwest along Faradayweg and an irradiation room at the far
end of the wing.
ey separated the three functions of irradiation,
measurement and chemistry to avoid contaminating one with radiation
from another.
All the rooms were fitted with worktables of unfinished raw
pine roughed out by a careful carpenter who took the trouble to add a
graceful taper to the legs.
On the table in the irradiation room rested
cylinders of beeswax-colored paraffin like angelfood cakes drilled for the
neutron sources, which were gram-strength radium salts mixed with
beryllium powder.
Handmade Geiger counters, fixed in hinged, hollowed-
out bricks of lead shielding on the table in the measurement room,
connected through thin coiling wires back to breadboard amplifiers worked
by silvered vacuum tubes like inverted bud vases.
e amplifiers actuated
gleaming brass clockwork counters with numbers showing black through
angled miniature windows on their spines.
Kraboard-covered 90-volt
Pertrix dry batteries that powered the system packed a shelf below the table.
Hahn’s laboratory table held the brackets, beakers, flasks, funnels and filters
of radiochemistry.
e two men moved in their work from room to room on
a regular schedule determined by the duration of the half-lives they were
studying.
ere would have been a pungency of nitrates in the air, mingled
with the aroma of Hahn’s inevitable cigar.
In his fiy-ninth year Hahn stooped slightly but looked younger than his
age.
His hairline had receded and his eyebrows had grown bushy; he had
trimmed back to the edge of his upper lip the waxed Prussian mustache of
his youth; his brown eyes still sparkled with warmth.
By now he was
unquestionably the ablest radiochemist in the world.
He needed all his forty
years’ experience to decode uranium.
He and Strassmann had begun their renewed examination of the three
“radium” isotopes early in December by attempting a purer separation from
uranium.
Strassmann suggested using barium chloride as a carrier rather
than the customary barium sulfate because the chloride, Hahn explains,
“forms beautiful little crystals” of exceptional purity.
960 ey wanted to be
sure their separations would be free of contamination from other
bombardment products with similar half-lives, the difficulty that had
muddled Curie and Savitch.
e procedure for the 86-minute activity they
were studying, which they called “Ra-III,” required them to irradiate about
fieen grams of purified uranium for twelve hours, wait several hours for
their more intense 14-minute “Ra-II” to retreat from the foreground by
decaying, then add barium chloride as a carrier and accomplish the
separation.
e Ra-III came out of the uranium solution with the barium,
but it refused then to remain behind during fractionation when the barium
crystallized away.
Instead it crystallized with the barium.
“e attempts to separate our artificial ‘radium isotopes’ from barium in
this way were unsuccessful,” Hahn would explain in his Nobel Prize lecture;
“no enrichment of the ‘radium’ was obtained.
It was natural to ascribe this
lack of success to the exceptionally low intensity of our preparations.
It was
always a question of merely a few thousands of atoms, which could only be
detected as individual particles by the Geiger-Müller counter.
Such a small
number of atoms could be carried away by the great excess of inactive
barium without any increase or decrease being perceptible.” 961 To check that
possibility they retrieved from storage a known radium isotope they oen
worked with, the isotope they called “mesothorium.” ey diluted it to
match the pale radioactivity of their few thousand atoms of Ra-III, then ran
it through barium precipitation and fractionation.
It separated away cleanly
from the barium.
eir technique was not at fault.
On Saturday, December 17, the day aer Hahn stormed the revenue office
on behalf of Meitner’s furniture, he and Strassmann carried out a further
heroic check.
ey mixed Ra-III with dilute mesothorium and precipitated
and fractionated the two substances together.
en the chemical evidence
was certain, whatever it might mean in physical terms: the mesothorium
remained in solution when the barium carrier crystallized out but Ra-III
went off with the barium, distributing itself uniformly and indivisibly
throughout the small pure crystals.
Hahn wrote an enthusiastic note in his
pocket appointment book to mark the day: “Exciting fractionation of
radium/barium/mesothorium.” 962
It seemed their “radium” isotopes must be barium, element 56, slightly
more than half as heavy as uranium and with just over half its charge.
Hahn
and Strassmann could hardly believe it.
ey conceived an even more
convincing experiment.
If their “radium” was really radium, then by beta
decay it ought to transform itself one step up the periodic table to actinium
(89).
If, on the other hand, it was barium (56), then by beta decay it ought to
transform itself one step up to lanthanum (57).
And lanthanum could be
separated from actinium by fractionation.
ey were carrying out this
definitive project late Monday night, December 19, when Hahn sent Meitner
the news.
“Perhaps you can suggest some fantastic explanation,” he wrote.963 “We
understand that it really can’t break up into barium....
So try to think of
some other possibility.
Barium isotopes with much higher atomic weights
than 137?
If you can think of anything that might be publishable, then the
three of us would be together in this work aer all.
We don’t believe this is
foolishness or that contaminations are playing tricks on us.”
He closed by wishing his friend a “somewhat bearable” Christmas.
Fritz
Strassmann added “very warm greetings and best wishes.
”964 Hahn posted
the letter to Stockholm late at night on his way home.
e two men took time from their readings to attend the annual KWI
Christmas party the next day, though Hahn had little joy of it with Meitner
gone.
965 ey continued the actinium-lanthanum experiment even as they
worked up the radium-barium findings.
Aer the party the institute would
close for Christmas; they kept a typist busy until the end but were unable to
finish their report.
Hahn had called Paul Rosbaud at Naturwissenschaen,
told him the news and asked him to make space in the next issue.966
Rosbaud was willing to pull a less urgent paper from the journal but
cautioned that the manuscript must be delivered no later than Friday,
December 23.
Hahn arranged for a laboratory assistant to serve as typist on
ursday.
In the meantime he and Strassmann would carry on alone.
Meitner received Hahn’s Monday-night letter in Stockholm on
Wednesday, December 21.
It was startling; if the results held she saw it
meant the uranium nucleus must fracture and she immediately wrote him
back:
Your radium results are very amazing.
A process that works with slow
neutrons and leads to barium!...
To me for the time being the hypothesis
of such an extensive burst seems very difficult to accept, but we have
experienced so many surprises in nuclear physics that one cannot say
without hesitation about anything: “It’s impossible.” 967
She was traveling on Friday to the village of Kungälv in the west of Sweden
for a week’s vacation, she told Hahn; “if you write me in the meantime please
address your letter there.” She sent him and his family “warmest
greetings...
and much love and the very best for the New Year.” 968
at day Hahn and Strassmann had finished the actinium-lanthanum
experiment—and confirmed lanthanum from barium decay.
In the late
evening, aer they turned off their counters, Hahn wrote his exiled colleague
again.
e paper was not yet finished; a phrase from the letter would be
reworked to more cautious language for the final dra: “Our radium proofs
convince us that as chemists we must come to the conclusion that the three
carefully-studied isotopes are not radium, but, from the standpoint of the
chemist, barium.” 969
Hahn had hoped Meitner might quickly find some physical explanation
for his unprecedented chemistry.
at would strengthen his conclusion and
also put Meitner’s name on the paper, the best possible Christmas gi.
With
the lanthanum confirmation at hand he could no longer delay.
As it was he
had withheld the news from physicists on his own staff and at the new
physics institute nearby.
Someone else—Curie and Savitch, for example—
might very well have made the same discovery.
And whatever the
explanation, the discovery was clearly of major importance, a reaction
unlike any other yet found.
“We cannot hush up the results,” Hahn wrote
Meitner, “even though they may be absurd in physical terms.
You can see
that you will be performing a good deed if you find an alternative
[explanation].
When we finish tomorrow or the day aer I will send you a
copy of the manuscript....
e whole thing is not very well suited for
Naturwissenschaen.
But they will publish it quickly.”
Hahn mailed the letter to Stockholm.
He did not yet know about Meitner’s
Kungälv vacation.
* * *
Leo Szilard’s work at the University of Rochester confirmed that no neutrons
came out when indium was irradiated.
On December 21, as Hahn and
Meitner exchanged their excited letters, Szilard advised the British
Admiralty by letter:
Further experiments...
have definitely cleared up the anomalies which I
have observed in 1936....
In view of this new work it does not now seem
necessary to maintain [my] patent...
nor would the waiving of the
secrecy of this patent serve any useful purpose.
I beg therefore to suggest
that the patent be withdrawn altogether.
970
Szilard’s faith in the possibility of a chain reaction, as he said later, had “just
about reached the vanishing point.
”971
* * *
Hahn and Strassmann had originally titled their paper “On the radium
isotopes produced by the neutron bombardment of uranium and their
behavior.” 972 With their new data they realized “radium” would no longer
do.
ey considered changing “radium” to “barium” throughout the paper.
But most of it had been written before the lanthanum experiment firmed
their convictions.
ey would have had to rewrite from beginning to end,
“especially,” says Hahn in retrospect, “since in view of this result its major
portion was not especially interesting any more.
”973 Christmas and the
journal deadline were upon them and they had no time.
ey decided to
juryrig what was on hand.
e results would be no less effective for being
inelegant.
ey substituted the noncommittal phrase “alkaline-earth metals”
for “radium isotopes” in the title—both barium and radium are
alkalineearth metals, as are beryllium, magnesium, calcium and strontium.
ey went through the dra putting equivocal quotation marks around their
many references to radium and actinium.
en they attached seven cautious
paragraphs at the end.
“Now we still have to discuss some newer experiments,” this final section
began, “which we publish rather hesitantly due to their peculiar results.”
ey then summarized their series of experiments:
We wanted to identify beyond any doubt the chemical properties of the
parent members of the radioactive series which were separated with the
barium and which have been designated as “radium isotopes.” We have
carried out fractional crystallizations and fractional precipitations, a
method which is well-known for concentrating (or diluting) radium in
barium salt solutions....
When we made appropriate tests with radioactive barium samples
which were free of any later decay products, the results were always
negative.
e activity was distributed evenly among all the barium
fractions....
We come to the conclusion that our “radium isotopes” have
the properties of barium.
As chemists we should actually state that the
new products are not radium, but rather barium itself.
Other elements
besides radium or barium are out of the question.
ey discussed actinium then, distinguished their work from that of Curie
and Savitch and pointed out that all so-called transuranics would have to be
reexamined.
Not quite prepared to usurp the prerogative of the physicists,
they closed on a tentative note:
As chemists we really ought to revise the decay scheme given above and
insert the symbols Ba, La, Ce [cerium], in place of Ra, Ac, [thorium].
However as “nuclear chemists,” working very close to the field of physics,
we cannot bring ourselves yet to take such a drastic step which goes
against all previous laws of nuclear physics.
ere could perhaps be a
series of unusual coincidences which has given us false indications.
Promising further experiments, they prepared to release their news to the
world.
Hahn mailed the paper and then felt the whole thing to be so
improbable “that I wished I could get the document back out of the mail
box”; or Paul Rosbaud came around to the KWI the same evening to pick it
up.974 Both stories survive Hahn’s later recollection.
Since Rosbaud knew the
paper’s importance and dated its receipt December 22, 1938, he probably
picked it up.
But Hahn also visited the mailbox that night, to send a carbon
copy of the seminal paper to Lise Meitner in Stockholm.
His misgivings at
publishing without her—or some dawning glimmer of the fateful
consequences that might follow his discovery—may have accounted for his
remembered apprehension.
* * *
e Swedish village of Kungälv—the name means King’s River—is located
some ten miles above the dominant western harbor city of Goteborg and six
miles inland from the Kattegat coast.
975 e river, now called North River,
descends from Lake Vanern, the largest freshwater lake in Western Europe;
at Kungälv it has cut a sheer granite southward-facing bluff, the precipice of
Fontin, 335 feet high.
e modern village is built along a single cobblestone
lane on the narrow talus between the bluff and the river, its back to the wall.
As Norwegian Kongahalla the village was founded at a less constricted
place downstream around A.D.
800.
But an island hill rises from the river at
Kungälv and is thus guarded by a natural moat, a defensive geography which
the precipice of Fontin reinforces.
In 1308, to mark the border there between
Norway and Sweden, the Norwegians began to build on that island hill a
monumental granite fortress, Bohus’ Fäste (i.e., King Bohus’ Fort), sod-
ridged block walls mazing inward and upward to a cylindrical tower of thick
stone with a conical roof that dominates the entire coastal valley.
An
accident of placement of three of the deep windows that penetrate the tower
—two open above, one centered below—transforms it into a face staring
with hollow eyes toward the Fontin bluff.
To soen the grimness of that face
the people of the valley named the tower Fars Hatt, Father’s Hat, as if it
evoked a workman in a cap.
rough four hundred years of occupation
Bohus’ Fäste was besieged fourteen times while the settlements in the valley
were put to the torch and the graveyard filled on the island below its hard
walls.
e village was ordered moved upriver onto the island in 1612.
e Danes
ruled Norway from the fieenth century to the early nineteenth century;
they ceded the Kungälv region, Bohuslän, to Sweden by the Treaty of
Roskilde in 1658.
Fire in 1676 burned the island village and its burghers
shied for safety to the narrow shore.
ey laid out their lane and strip of
houses extending west and east from a cobblestone marketplace where the
talus widened to make room.
Despite its fortress Kungälv is peaceful,
especially in winter with the river frozen and a depth of clean snow on the
ground.
Its snug wooden houses, painted pastel, enclose rooms cozy with
ships’ chests and china cabinets and lace curtains, warmed by corner
fireplaces faced with decorative tile, aromatic with coffee and baking.
Eva
von Bahr-Bergius and her husband Niklas built a house there in 1927, larger
than most Kungälv houses but constructed in the same style.
In 1938 Lise
Meitner was alone in Stockholm.
Otto Frisch was alone in Copenhagen, his
mother, Meitner’s sister, beyond reach in Vienna, his father incarcerated at
Dachau, a victim of Kristallnacht.
e Bergiuses therefore considerately
invited aunt and nephew to Kungälv for Christmas dinner.
Meitner le Stockholm Friday morning, two days before Christmas.
Frisch took the train ferry across from Denmark.976 His aunt arrived before
him and registered at a quiet inn on Västra gatan, West Street, where they
both would stay, a pale green building much like its modest neighbors but
with a café on the ground floor.977 It faced a shadowed strip of garden north
across the lane; above the stunted garden trees the dark bluff loomed.
e
other way, behind the inn, the flat, snow-covered flood plain of the river
extended into open woods.
e Bergiuses’ house was a short walk eastward
past the marketplace and the white church.
Tired from travel, Frisch and
Meitner met only briefly in the evening when Frisch came in.978
In Copenhagen that winter he had been studying the magnetic behavior
of neutrons.
To further his work he needed a strong, uniform magnetic field,
and on his way to Kungälv he had sketched out a large magnet he meant to
design and build.979 He came downstairs on the morning before Christmas
prepared to interest his aunt in his plans.
She was already at breakfast and
had no intention of discussing magnets: she had brought Hahn’s December
19 letter downstairs with her and insisted Frisch read it.980 He did.
“Barium,”
he told her, “I don’t believe it.
ere’s some mistake.” 981 He tried to change
the subject to his magnet; she changed it back to barium.
“Finally,” says
Meitner, “...
we both became absorbed in my problem.
”982 ey decided to
go for a walk to see what they could puzzle out.
Frisch had brought cross-country skis and wanted to use them.
He was
concerned that his aunt would be unable to keep up.
She could walk as fast
as he could ski on level ground, she told him.
She could and did.
He fetched
his skis and they went out, probably eastward to the Kungälv marketplace,
which gave onto the flood plain of the river, then across the frozen river and
into the open woods beyond.
“But it’s impossible,” Frisch remembers them saying in their collective
effort to understand.
“You couldn’t chip a hundred particles off a nucleus in
one blow.
983 You couldn’t even cut it across.
If you tried to estimate the
nuclear forces, all the bonds you’d have to cut all at once—it’s fantastic.
It’s
quite impossible that a nucleus could do that.” irty years aerward Frisch
summarized their thinking in more formal terms:
But how could barium be formed from uranium?
No larger fragments
than protons or helium nuclei (alpha particles) had ever been chipped
away from nuclei, and the thought that a large number of them should be
chipped off at once could be dismissed; not enough energy was available
to do that.
Nor was it possible that the uranium nucleus could have been
cleaved right across.
Indeed a nucleus was not like a brittle solid that
could be cleaved or broken; Bohr had stressed that a nucleus was much
more like a liquid drop.
984
e liquid-drop model made a division of the nucleus seem possible.
ey
sat down on a log.
Meitner found a scrap of paper and a pencil in her purse.
She drew circles.
“Couldn’t it be this sort of thing?” 985
Frisch: “Now, she always rather suffered from an inability to visualize
things in three dimensions, whereas I had that ability quite well.
I had, in
fact, apparently come around to the same idea, and I drew a shape like a
circle squashed in at two opposite points.
”986
“Well, yes,” Meitner said, “that is what I mean.
”987 She had meant to draw
what Frisch had drawn, a liquid drop elongated like a dumbbell, but had
drawn it end-on, indicating with a smaller dashed circle inside a larger solid
circle the dumbbell’s waist.
Frisch: “I remember that I immediately at that instant thought of the fact
that electric charge diminishes surface tension.” 988 e liquid drop is held
together by surface tension, the nucleus by the analogous strong force.
But
the electrical repulsion of the protons in the nucleus works against the
strong force, and the heavier the element, the more intense the repulsion.
Frisch continues:
And so I promptly started to work out by how much the surface tension
of a nucleus would be reduced.
I don’t know where we got all our
numbers from, but I think I must have had a certain feeling for the
binding energies and could make an estimate of the surface tension.
Of
course we knew the charge and the size reasonably well.
And so, as an
order of magnitude, the result was that at a charge [i.e., an atomic
number] of approximately 100 the surface tension of the nucleus
disappears; and therefore uranium at 92 must be pretty close to that
instability.
ey had discovered the reason no elements beyond uranium exist naturally
in the world: the two forces working against each other in the nucleus
eventually cancel each other out.
ey pictured the uranium nucleus as a liquid drop gone wobbly with the
looseness of its confinement and imagined it hit by even a barely energetic
slow neutron.
e neutron would add its energy to the whole.
e nucleus
would oscillate.
In one of its many random modes of oscillation it might
elongate.
Since the strong force operates only over extremely short distances,
the electric force repelling the two bulbs of an elongated drop would gain
advantage.
e two bulbs would push farther apart.
A waist would form
between them.
e strong force would begin to regain the advantage within
each of the two bulbs.
It would work like surface tension to pull them into
spheres.
e electric repulsion would work at the same time to push the two
separating spheres even farther apart.
Eventually the waist would give way.
Two smaller nuclei would appear
where one large nucleus had been before—barium and krypton, for
example:
“en,” Frisch recalls, “Lise Meitner was saying that if you really do form
two such fragments they would be pushed apart with great energy.” 989 ey
would be pushed apart by the mutual repulsion of their gathered protons at
one-thirtieth the speed of light.
Meitner or Frisch calculated that energy to
be about 200 MeV: 200 million electron volts.
An electron volt is the energy
necessary to accelerate an electron through a potential difference of one volt.
Two hundred million electron volts is not a large amount of energy, but it is
an extremely large amount of energy from one atom.
e most energetic
chemical reactions release about 5 eV per atom.
Ernest Lawrence was that
year building a cyclotron with a nearly 200-ton magnet with which he hoped
to accelerate particles by as much as 25 MeV.
Frisch would calculate later
that the energy from each bursting uranium nucleus would be sufficient to
make a visible grain of sand visibly jump.
In each mere gram of uranium
there are about 2.5 × 1021 atoms, an absurdly large number, 25 followed by
twenty zeros: 2,500,000,000,000,000,000,000.
ey asked themselves what the source of all that energy could be.
at
was the crux of the problem and the reason no one had credited the
possibility before.
Neutron captures that had been observed before had
involved much smaller energy releases.
When she was thirty-one, in 1909, Meitner had met Albert Einstein for
the first time at a scientific conference in Salzburg.
He “gave a lecture on the
development of our views regarding the nature of radiation.
990 At that time I
certainly did not yet realize the full implications of his theory of relativity.”
She listened eagerly.
In the course of the lecture Einstein used the theory of
relativity to derive his equation E = mc 2, with which Meitner was then
unfamiliar.
Einstein showed thereby how to calculate the conversion of mass
into energy.
“ese two facts,” she reminisced in 1964, “were so
overwhelmingly new and surprising that, to this day, I remember the lecture
very well.”
She remembered it in 1938, on the day before Christmas.
She also “had
the packing fractions in her head,” says Frisch—she had memorized Francis
Aston’s numbers for the mass defects of nuclei.991 If the large uranium
nucleus split into two smaller nuclei, the smaller nuclei would weigh less in
total than their common parent.
How much less?
at was a calculation she
could easily work: about one-fih the mass of a proton less.
Process one-fih
of the mass of a proton through E = mc 2.
“One fih of a proton mass,” Frisch
exclaims, “was just equivalent to 200 MeV.
So here was the source for that
energy; it all fitted!” 992
ey converted not quite so suddenly as that.
ey may have been excited,
but Meitner at least was profoundly wary.
is new work called her previous
four years’ work with Hahn and Strassmann into doubt; if she was right
about the one she was wrong about the other, just when she had escaped
from Germany into the indifferent world of exile and needed most to
confirm her reputation.
“Lise Meitner sort of kept saying, ‘We couldn’t have
seen it.
is was so totally unexpected.
Hahn is a good chemist and I trusted
his chemistry to correspond to the elements he said they corresponded to.
Who could have thought that it would be something so much lighter?’ ” 993
Christmas dinner at the Bergiuses’ came and went.
Frisch skied and
Meitner walked.
Nineteen thirty-eight was ticking to its end.
With a week to
pass in a small village they would certainly have visited the fortress and
looked down from its ramparts onto the snow-covered valley, onto centuries
of violent graves.
ough they understood its energetics now, the discovery
was still only physics to them; they did not yet imagine a chain reaction.
Hahn’s letter of December 21, confirming lanthanum, was still not
forwarded from Stockholm, nor was the carbon copy of the
Naturwissenschaen paper.
994 Hahn was eager to win Meitner’s support and
wrote Kungälv directly on the Wednesday aer Christmas to woo her.
Careful not to seem to usurp her place, he called the discovery his “barium
fantasy” and questioned everything except the presence of barium and the
absence of actinium, taking the humble chemist’s part.
“Naturally, I would
be very interested to hear your frank opinion.995 Perhaps you could compute
and publish something.” He had continued to hold off telling other
physicists, though he itched for physical confirmation of his chemistry.
It
was as though a maker of hand axes had discovered fire by striking flints
while the sorcerers pondered how to harness lightning.
He might hardly
believe his luck and urgently seek their authentication even though he knew
what burned his hand was real.
e letter reached Kungälv on ursday; by return mail that day Meitner
responded that the radium-barium finding was “very exciting.
Otto R[obert]
and I have already puzzled over it.
”996 But she let slip no answer to the
puzzle and she asked about the lanthanum result.
Friday she sent Hahn a postcard: “Today the manuscript arrived.” An
important page was missing but it was all “very amazing.” 997 Nothing more;
Hahn must have bitten his lip.
In Dahlem Rosbaud passed along the galley proofs.
Hahn was more
certain now of his findings.
e manuscript had set the barium results
“against all previous laws of nuclear physics.” He moderated the phrase in
proof to “against all previous experience.” 998
But even with the carbon copy, the missing page and the December 21
letter finally at hand in Kungälv, Meitner hesitated to leap.
On January 1,
aer conveying New Year’s greetings to Hahn, she wrote: “We have read
your work very thoroughly and consider it perhaps possible energetically
aer all that such a heavy nucleus bursts.” She veered off to worry about
their misbegotten transuranics, “not a good reference for my new start.
”999
Frisch added a New Year’s wish of his own and a more genial reservation: “If
your new findings are really true, it would certainly be of the greatest
interest and I am very curious about further results.” 1000
Meitner returned to Stockholm later that day and Frisch to Copenhagen.
He was “keen to submit our speculations—it wasn’t really more at that time
—to Bohr.” 1001 e note of hesitancy in their letter to Hahn suggests they
sought the authority of Bohr’s blessing.
Frisch saw him on January 3: “I had
hardly begun to tell him, when he struck his forehead with his hand and
exclaimed, ‘Oh what idiots we have all been!
Oh but this is wonderful!
is
is just as it must be!’ ” eir conversation lasted only a few minutes, Frisch
wrote his aunt that day, “since Bohr immediately and in every respect was in
agreement with us....1002, 1003 [He] still wants to consider this quantitatively this evening and to talk with me again about it tomorrow.” 1004
In Stockholm that day Meitner had received Hahn’s revised proofs.
Independently they quieted her doubt.
She wrote Hahn emphatically: “I am
fairly certain now that you really have a splitting towards barium and I
consider it a wonderful result for which I congratulate you and Strassmann
very warmly....
You now have a wide, beautiful field of work ahead of you.
And believe me, even though I stand here very empty-handed at the
moment, I am still happy about the marvelousness of these findings.” 1005
Now those findings needed interpretation.
Aunt and nephew outlined a
theoretical paper by long-distance telephone.
Frisch draed it Friday,
January 6, and that evening took the trolley to the House of Honor to
discuss it with Bohr, who was leaving for the United States the next morning
for a term of work at the Institute for Advanced Study.1006 ere was time
the next morning to type only part of the dra; Frisch delivered two pages to
Bohr at the train station from which he and his nineteen-year-old son Erik
were departing for Göteborg harbor.
On the assumption that Frisch would
immediately send the paper along to Nature Bohr promised not to mention
it to their American colleagues until he heard from Frisch that it had been
received and was in press.
Among the notes he brought to that final
discussion Frisch mentioned an experiment to confirm by physical means
the Dahlem chemistry.
1007
Hahn’s and Strassmann’s article had been published in Berlin on January
6.
When it arrived in Copenhagen the next day Frisch thought to go over the
whole business with George Placzek.1008 Placzek was characteristically
skeptical and characteristically witty about it.
Uranium already suffered
from alpha decay, Frisch remembers him scoffing; to think that it could be
made to burst as well “was like dissecting a man killed by a falling brick and
finding that he would have died of cancer.” 1009 Placzek suggested that Frisch
use a cloud chamber to look for energetic fragments that would prove the
nucleus had split.
e institute’s radium-based neutron sources would fog a
cloud-chamber photograph with gamma radiation, Frisch realized.
But a
simple ionization chamber would do.
“One would expect fastmoving nuclei,
of atomic number about 40–50 and atomic weight 100–150, and up to 100
MeV energy to emerge from a layer of uranium bombarded with neutrons,”
he explained his experiment in a subsequent report.
“In spite of their high
energy, these nuclei should have a range, in air, of a few millimetres only, on
account of their high effective charge...
which implies very dense
ionization.
”1010 In the course of their short passage his highly charged nuclear fragments would strip about 3 million electrons from the nuclei of
air gases.
ey should be easy to find.
His chamber consisted of “two metal plates separated by a glass ring about
1 cm.
high.” e charged plates, which would collect the air ions, connected
to a simple amplifier, which connected to an oscilloscope.
To the bottom
plate he attached a piece of uranium-coated foil.
He set up the experiment in
the basement of the institute and retrieved three of the neutron sources from
the covered well.
He placed the sources close to the foil and looked for the
expected nuclei to emerge.
Since they were highly energetic and strongly
ionizing they would create quick, sharp, vertical pulses of the sweeping
green beam of the oscilloscope.
Frisch started measurements on the aernoon of Friday, January 13, and
“pulses at about the predicted amplitude and frequency (one or two per
minute) were seen within a few hours.” 1011, 1012 He ran checks with either the neutron sources or the uranium lining removed.
He wrapped the sources
with paraffin to slow the neutrons and “enhanced the effect by a factor of
two.” He continued measurements “until six in the morning to verify that
the apparatus was working consistently.” As had Werner Heisenberg before
him, he lived upstairs at the institute; exhausted, he climbed the stairs to
bed.
He remembers thinking that 13 had proved once again to be his lucky
number.
Even luckier than that: “At seven in the morning I was knocked out of bed
by the postman who brought a telegram to say that my father had been
released from concentration camp.” 1013 His parents would move to
Stockholm and share an apartment with his aunt, whose possessions, thanks
to Hahn, were eventually shipped.
In “a state of slight confusion” Frisch spent the next day repeating the
experiment for anyone who cared to see.1014 One who came down in the
morning to the basement laboratory was a black-haired, blue-eyed
American biologist of Irish heritage named William A.
Arnold who was
studying on a Rockefeller Fellowship with George de Hevesy.
1015 Arnold was
thirtyfour, Frisch’s age, on leave from the Hopkins Marine Station at Pacific
Grove, California.
He had made his way to Europe from San Francisco the
previous September by freighter with his wife and young daughter.
He could
have gone to Berkeley to pick up radioisotope technique, but would have
missed living in Copenhagen, learning from de Hevesy—would have missed
contributing a coinage to the gamble that is history.
Frisch showed the
American the experiment and pointed out the pulses on the oscilloscope.
“From the size of the spikes,” Arnold recalls, “it was clear that they must
represent 100–200 MeV, very much larger than the spikes from [uranium’s
natural background of] alpha particles.”
Later that day Frisch looked me up and said, “You work in a microbiology
lab.
What do you call the process in which one bacterium divides into
two?” And I answered, “binary fission.” He wanted to know if you could
call it “fission” alone, and I said you could.
Frisch the sketch artist, good at visualizing as his aunt was not, had
metamorphosed his liquid drop into a dividing living cell.
1016 ereby the
name for a multiplication of life became the name for a violent process of
destruction.
“I wrote home to my mother,” says Frisch, “that I felt like
someone who has caught an elephant by the tail.” 1017
Aunt and nephew conferred by telephone further over the weekend to
prepare not one but two papers for Nature: a joint explanation of the
reaction and Frisch’s report of the confirming evidence of his
experiment.
1018 Both reports—“Disintegration of uranium by neutrons: a
new type of nuclear reaction” and “Physical evidence for the division of
heavy nuclei under neutron bombardment”—used the new term “fission.”
Frisch finished the two papers on Monday evening, January 16, and posted
them airmail to London the next morning.1019 Since he and Bohr had
already discussed the theoretical paper and since the experiment only
confirmed the HahnStrassmann discovery, he did not hurry to let Bohr
know.
* * *
Bohr sailed on the Swedish-American liner Drottningholm with his son Erik
and the Belgian theoretician Léon Rosenfeld.
“As we were boarding the
ship,” Rosenfeld recalls, “Bohr told me he had just been handed a note by
Frisch, containing his and Lise Meitner’s conclusions; we should ‘try to
understand it.’ ” at meant a working voyage; a blackboard was duly
installed in Bohr’s stateroom.
e North Atlantic was stormy in that season;
it made him “rather miserable, all the time on the verge of seasickness” but
hardly stopped the work.1020 e first question he wanted to answer was
why, if the nucleus oscillated more or less randomly when it was bombarded,
it seemed to prefer splitting into two parts rather than some other number.
He was satisfied when he saw that the heaviest nuclei, because of their
instability, require no more energy to split than they do to emit a single
particle.
It was a question of probabilities and two fragments were greatly
more probable than a crowd.
e Fermis had arrived in New York on January 2, Laura feeling distinctly
alien, Enrico announcing with his usual mock solemnity, “We have founded
the American branch of the Fermi family.
”1021 ey put up temporarily at
the King’s Crown Hotel, opposite Columbia University, where Szilard was
also living.
George Pegram, the tall, so-spoken Virginian who was
chairman of the physics department and dean of graduate studies at
Columbia, had met the Fermis as they debarked the Franconia; now in turn
they waited at dockside to meet Bohr.
e American theoretician John
Archibald Wheeler, then twenty-nine years old, who had worked with Bohr
in Copenhagen in the mid-1930s and would be working with him again at
Princeton, joined them on the crowded West 57th Street pier.
He had taught
his regular Monday morning class, then caught a midday train.
As the Drottningholm berthed, at 1 P.M.
on January 16, Laura Fermi saw
Bohr on an upper deck leaning on the railing searching the crowd.
She
thought him worn when they met: “During the short time that had elapsed
since our visit to his home, Professor Bohr seemed to have aged.
For the last
few months he had been extremely preoccupied about the political situation
in Europe, and his worries showed on him.
He stooped like a man carrying a
heavy burden.
His gaze, troubled and insecure, shied from the one to the
other of us, but stopped on none.” 1022 No doubt Bohr was worried about
Europe.
He had also been seasick.
He had business in New York; he and Erik went off with the Fermis.
Wheeler took Léon Rosenfeld along to Princeton.
1023 Keeping his promise
to Frisch, Bohr had not mentioned the Hahn-Strassmann discovery and the
Frisch-Meitner interpretation to either Fermi or Wheeler, but he had
neglected to tell Rosenfeld of his pledge.
Rosenfeld thought Frisch and
Meitner had already sent off the paper that would give their work of
interpretation priority.
He passed on to Wheeler what Bohr had passed on to
him.
“In those days,” Wheeler remembers, “I was in charge of the Monday
evening journal club”—a weekly gathering of Princeton physicists to discuss
the latest studies they found in physics journals, a way of keeping up.1024 “It
was the custom to get three things reported then, and here was something
hot, as I had learned from Rosenfeld on the train.” America first heard the
news of the splitting of uranium—the term “fission” had not yet crossed the
Atlantic—at the Princeton physics department journal club on the chill
Monday evening of January 16, 1939.
“e effect of my talk on the American
physicists,” says Rosenfeld ruefully, “was more spectacular than the fission
phenomenon itself.
ey rushed about spreading the news in all
directions.
”1025, 1026
Bohr arrived in Princeton the next day to take up residence and Rosenfeld
casually mentioned the journal club talk.
1027 “I was immediately frightened,”
Bohr wrote his wife that night, “as I had promised Frisch I would wait until
Hahn’s note appeared and his own was sent off.” It was more than a point of
honor, though that would have been sufficient in itself to trigger the Bohr
conscience.
It was also that Meitner and Frisch were refugees who could use
so spectacular a coup to establish themselves securely in exile.
Bohr had at
hand the work he and Rosenfeld had accomplished aboard the
Drottningholm; for the next three days he labored to convert it into a letter to
Nature that would give credit pointedly at the outset to Meitner and Frisch.
ree days to produce a seven-hundred-word paper was for Niels Bohr great
haste.
“Can you guess where I found out about [Bohr’s news]?” asks Eugene
Wigner.
“In...
the [Princeton] infirmary.
Because I contracted jaundice and
was in the infirmary for six weeks.
”1028 Wigner and Princeton had not
immediately got along; in 1936 “they said I should look for another job.” 1029
Princeton then, he thought, was “an ivory tower; people did not have any
normal thinking about the facts of life and so forth and they looked down
upon me.” He sought another job and found one at the University of
Wisconsin at Madison.
“From the second day on I felt at home there.
Somebody suggested we go to the track and we ran around the track and we
were friends.
We talked not only about the most difficult problems but about
the daily events.
We got down to earth almost.” He met a young American
woman in Wisconsin; they were quickly married.
She became ill:
I tried to conceal it from her that she had cancer and that there was no
hope for her surviving.
She was in a hospital in Madison and then she
went to see her parents and I went with her but I didn’t want to stay with
her parents, of course, because I was, aer all, a stranger to her parents.
I
went for a little while away to Michigan, Ann Arbor, and then I came back
and saw her in her bed at her parents’.
And then she told me essentially
that she knows that she is close to death.
She said, “Should I tell you where
our suitcases are?” So she knew when she talked to me.
I tried to conceal
it from her because I felt that it would be better if a reasonably young
person does not realize that she is doomed.
Of course, we are all doomed.
He returned to Princeton in 1938, the university by then having more
sensibly assessed his worth (a sophisticated and highly respected
theoretician, Wigner shared the Nobel Prize in Physics in 1963 for his work
on the structure of the nucleus).
Aer Bohr’s arrival Szilard traveled down from New York to visit his sick
friend and won a long-overdue surprise:
Wigner told me of Hahn’s discovery.
1030 Hahn found that uranium breaks
into two parts when it absorbs a neutron....
When I heard this I
immediately saw that these fragments, being heavier than corresponds to
their charge, must emit neutrons, and if enough neutrons are emitted...
then it should be, of course, possible to sustain a chain reaction.
All the
things which H.
G.
Wells predicted appeared suddenly real to me.
At Wigner’s bedside in the Princeton infirmary the two Hungarians debated
what to do.
In the meantime Bohr had sent his letter for Nature to Frisch in
Copenhagen, asking him to forward it on “if, as I hope, Hahn’s article has
already been published and your and your aunt’s note has already been
submitted.” He asked for the “latest news” on that front and wondered “how
the experiments are proceeding.” 1031 In a postscript he added that he had
just seen the Hahn-Strassmann paper in Naturwissenschaen.
Ideas infect like viruses.
e point of origin of the fission infection was
Dahlem.
From there it spread to Stockholm, to Kungälv, to Copenhagen.
It
crossed the Atlantic with Bohr and Rosenfeld.
I.
I.
Rabi and the young
California-born theoretician Willis Eugene Lamb, Jr., two Columbia men
working at Princeton that week, both heard the news, Lamb perhaps from
Wheeler, Rabi from Bohr himself.
1032 ey returned to New York
—“probably Friday night,” Lamb thinks.
1033 Rabi says he told Fermi.
1034 In 1954 Fermi credited Lamb: “I remember one aernoon Willis Lamb came
back very excited and said that Bohr had leaked out great news.” 1035 Lamb
recalls “spreading it around” but does not recall specifically telling Fermi.
1036
Possibly both men talked to the Italian laureate within a space of hours; it
was information he of all physicists would most need to hear, since the
Nobel lecture he had delivered only a month earlier, not yet printed, was
now partly obsolete and an embarrassment.
(Fermi confined revision to a
footnote: “e discovery by Hahn and Strassmann...
makes it necessary to
reexamine all the problems of the transuranic elements, as many of them
might be found to be products of a splitting of uranium.
”1037 e many other
radioactivities he and his group identified and his slow-neutron discovery
still secured his Nobel Prize.)
Szilard also hoped to talk to Fermi: “I thought that if neutrons are in fact
emitted in fission, this fact should be kept secret from the Germans.
So I was
very eager to contact Joliot and to contact Fermi, the two men who were
most likely to think of this possibility.
”1038 He had borrowed Wigner’s
apartment and had not yet le Princeton.
“I got up one morning and wanted
to go out.
It was raining cats and dogs.
I said, ‘My God, I am going to catch
cold!’ Because at that time, the first years I was in America, each time I got
wet I invariably caught a bad cold.” He had to go out anyway.
“I got wet and
came home with a high fever, so I was not able to contact Fermi.”
Fever or not, by January 25—Wednesday—Szilard had returned to New
York, had seen the Hahn-Strassmann paper and was writing Lewis Strauss,
whose patronage might now be more important than ever:
I feel I ought to let you know of a very sensational new development in
nuclear physics.
1039 In a paper...
Hahn reports that he finds when
bombarding uranium with neutrons the uranium breaking up....
is is
entirely unexpected and exciting news for the average physicist.
e
Department of Physics at Princeton, where I spent the last few days, was
like a stirred-up ant heap.
Apart from the purely scientific interest there may be another aspect of
this discovery, which so far does not seem to have caught the attention of
those to whom I spoke.
First of all it is obvious that the energy released in
this new reaction must be very much higher than all previously known
cases....
is in itself might make it possible to produce power by means
of nuclear energy, but I do not think that this possibility is very exciting,
for...
the cost of investment would probably be too high to make the
process worthwhile....
I see...
possibilities in another direction.
ese might lead to large-
scale production of energy and radioactive elements, unfortunately also
perhaps to atomic bombs.
is new discovery revives all the hopes and
fears in this respect which I had in 1934 and 1935, and which I have as
good as abandoned in the course of the last two years.
At present I am
running a high temperature and am therefore confined to my four walls,
but perhaps I can tell you more about these new developments some other
time.
e same day Fermi stepped into the office of John R.
Dunning, a
Columbia experimentalist whose specialty was neutrons, to propose an
experiment.
Dunning, his graduate student Herbert Anderson and others at
Columbia had built a small cyclotron in the basement of Pupin Hall, the
modern thirteen-story physics tower that faces downtown Manhattan from
behind the library on the upper campus.1040 A cyclotron was a potent source
of neutrons; the two men talked about using it to perform an experiment
similar to Frisch’s experiment of January 13–14, of which they were as yet
unaware.
ey discussed arrangements over lunch at the Columbia faculty
club and aerward back at Pupin.
While Fermi was away from his desk Bohr arrived to tell him what he
already knew.
Finding an empty office, Bohr took the elevator to the
basement, to the cyclotron area, where he turned up Herbert Anderson:
He came right over and grabbed me by the shoulder.
Bohr doesn’t lecture
you, he whispers in your ear.
“Young man,” he said, “let me explain to you
about something new and exciting in physics.” en he told me about the
splitting of the uranium nucleus and how naturally this fits in with the
idea of the liquid drop.
I was quite enchanted.
Here was the great man
himself, impressive in his bulk, sharing his excitement with me as if it
were of the utmost importance for me to know what he had to say.
1041
Bohr was en route to a conference in Washington on theoretical physics that
would begin the next aernoon; he le to catch his train without seeing
Fermi.
As soon as Bohr was gone Anderson hunted up the Italian, who had
returned to his office by now.
“Before I had a chance to say anything,”
Anderson remembers, “he smiled in a friendly fashion and said, ‘I think I
know what you want to tell me.
Let me explain it to you....’ I have to say
that Fermi’s explanation was even more dramatic than Bohr’s.” 1042
Fermi helped Anderson and Dunning begin organizing the experiment he
had discussed with Dunning earlier in the day.
Anderson happened not long
before to have built an ionization chamber and linear amplifier.
“All we had
to do was prepare a layer of uranium on one electrode and insert it into the
chamber.
at same aernoon we set up everything at the cyclotron.
But the
cyclotron was not working very well that day.
en I remembered some
radon and beryllium which had been used as a source of neutrons in earlier
experiments.
It was a lucky thought.
”1043 It came too late in the day; Fermi
was also attending the Washington conference and had to leave.
Anderson
and Dunning closed up shop.
e Washington Conferences on eoretical Physics, of which the 1939
meeting would be the fih, were a George Gamow invention.
He had
stipulated their creation as a condition of his employment at George
Washington University in 1934.
He took Bohr’s annual gathering in
Copenhagen for a model; since there was no comparable assembly in the
United States at the time, the Washington Conferences met with immediate
success.
At the instigation of Merle Tuve, Ernest Lawrence’s boyhood friend
and the driving force at the Department of Terrestrial Magnetism of the
Carnegie Institution of Washington, the Carnegie Institution co-sponsored
the conferences with GWU, though expenses were modest, for travel only,
no more in total than five or six hundred dollars a year.
People attended
because they were interested.
Edward Teller recalls the meetings as “in
general small and exciting, thoroughly absorbing, and also a little tiring.
Somehow, most of the running of the conferences Gamow le to me.” 1044
e two men simply chose a topic and made up a list of invitees.
Graduate
students crowded in to listen.
is year’s topic was low-temperature physics.
Bohr sought out Gamow as soon as he arrived in Washington that
evening.
Gamow in turn called Teller: “Bohr has just come in.
He has gone
crazy.
He says a neutron can split uranium.” Teller thought of Fermi’s
experiments in Rome and the mess of radioactivities they produced and
“suddenly understood the obvious.” 1045 In Washington Fermi learned to his
further disappointment from Bohr that Frisch was supposed to have done
an experiment similar to the one le unfinished at Columbia.
“Fermi...
had
no idea before that Frisch had made the experiment,” Bohr wrote Margrethe
a few days later.
“I had no right to prevent others from experimentation, but
I emphasized that Frisch had also spoken of an experiment in his notes.
I
said that it was all my fault that they all heard about Frisch and Meitner’s
explanation, and I earnestly asked them to wait [to make a public
announcement] until I received a copy of Frisch’s note to Nature, which I
hoped would be waiting for me at Princeton [i.e., aer the conference].” 1046
Fermi, understandably, seems to have argued against further delay.
Herbert Anderson returned to the basement of Pupin Hall that
evening.1047 He retrieved his neutron source.
He calculated how many alpha
particles the uranium oxide coated on a metal plate inside his ionization
chamber would eject spontaneously in its normal process of radioactive
decay: three thousand per minute.
He calculated the probability of ten of
those alphas appearing simultaneously to produce a spurious high-energy
kick of the scanning beam of his oscilloscope: “practically never,” he
concluded in his laboratory notebook.
He set the neutron source beside the ionization chamber a little aer 9 P.M.
and began observing the effect on the oscilloscope.
“Most kicks are due to.4
cm range α part[icles] [of approximately].65 M[e]V,” he noted.
en he saw
what he was looking for: “Now large kicks which occur infrequently about 1
every 2 minutes.” He counted them against the clock.
In 60 minutes he had
counted 33 large kicks.
He removed the neutron source.
“In 20 min” without
a neutron source, he wrote, “0 counts.” It was the first intentional
observation of fission west of Copenhagen.
Dunning showed up later that evening, Anderson remembers, and “was
very excited by the result I’d gotten.” Anderson thought Dunning would
telegraph Fermi immediately, but he seems not to have done so.
1048 Frisch,
as he told Bohr later, had cabled no news of his confirming Copenhagen
experiment because it seemed to him “just additional evidence of a
discovery already made” and “cabling to you would have appeared unmodest
to me.” 1049 Dunning, despite his excitement at seeing the new phenomenon
for himself, may have felt the same way.
Bohr woke to his dilemma.
e conference would begin at two.
As
recently as three days previously he had written Frisch again, chiding him
for not sending a copy of his and Meitner’s Nature note.
But he was less
concerned now with that delay than he was with protecting the priority of
Frisch’s experiment, if any.
Reluctantly he acceded to public announcement,
stressing, he wrote Frisch aerward, “that no public account...
could
legitimately appear without mentioning your and your aunt’s original
interpretation of the Hahn results.” 1050
Fiy-one participants sat for a photograph in the course of the Fih
Washington Conference, and even a partial list of their names confirms the
event’s prestige.1051 Otto Stern attended; Fermi; Bohr; Harold Urey of
Columbia, who won the 1934 Nobel Prize in Chemistry for isolating a heavy
form of hydrogen, deuterium, that carried a neutron in its nucleus; Gregory
Breit, a waspish but inspired theoretician; Rabi; George Uhlenbeck, then at
Columbia, who had been Paul Ehrenfest’s assistant; Gamow; Teller; Hans
Bethe down from Cornell; Léon Rosenfeld; Merle Tuve.
Conspicuously
absent was the Western crowd, probably because the two sponsoring
institutions chose not to budget such long-distance travel.
Gamow opened the meeting by introducing Bohr.1052 His news galvanized
the room.
A young physicist watching from the back saw an immediate
application.
Richard B.
Roberts, Princeton-trained, worked with Tuve at the
Department of Terrestrial Magnetism, the experimental section of the
Carnegie Institution, located in a parklike setting in the Chevy Chase area of
the capital.
Roberts—thin, vigorous, with a strong jaw and wavy dark hair—
still remembered the occasion vividly in 1979 in a dra autobiography:
e eo.
Phys.
Conference for 1939 was on the topic of low temperatures
and I was not eager to attend.
However, I went down to sit in the back row
of the meeting....
Bohr and Fermi arrived and Bohr proceeded to reveal
his news concerning the Hahn and Strassmann experiments....
He also
told of Meitner’s interpretation that the uranium had split.
As usual he
mumbled and rambled so there was little in his talk beyond the bare facts.
Fermi then took over and gave his usual elegant presentation including all
the implications.1053
Roberts noted in a letter to his father the Monday aer the conference ended
that “Fermi also...
described an obvious experiment to test the theory”—
Frisch’s experiment, Fermi’s, Dunning’s and Anderson’s experiment.
“e
remarkable thing is that this reaction results in 200 million volts of energy
liberated and brings back the possibility of atomic power.
”1054
Bohr was calling the fission fragments “splitters.” For the time being
everyone borrowed that comical usage.
Lawrence R.
Hafstad, a longtime
associate of Tuve, was sitting beside Roberts.
When Fermi finished, the two
men looked at each other, got up, le the meeting and lit out for the DTM.
If
“splitters” issued forth from uranium they intended to be among the first to
see them.
* * *
In New York that day Szilard dragged himself to the nearest Western Union
office and cabled the British Admiralty:
KINDLY DISREGARD MY RECENT LETTER STOP WRITING1055
e secret patent had revived.
* * *
Naturwissenschaen reached Paris about January 16.
One of Frédéric Joliot’s
associates recalls that “in a rather moving meeting [Joliot] made a report on
this result to Madame Joliot and myself aer having locked himself in for a
few days and not talked to anybody.
”1056, 1057 e Joliot-Curies were once again appalled to find they had barely missed a major discovery.
In the next
few days Joliot independently deduced the large energy release and
considered the possibility of a chain reaction, as Szilard had thought he
might.
He tried to track down the neutrons from fission first, found that
approach difficult, then set up an experiment somewhat like Frisch’s.
He
detected fission fragments on January 26.
* * *
e newest building on the DTM grounds was the Atomic Physics
Observatory, the working contents of which had just been brought on line
two weeks before: a new 5 MV pressure Van de Graaff generator that Tuve,
Roberts and their colleagues had built for $51,000 to extend their studies in
the structure of the nucleus.
e Van de Graaff was named for the Alabama-
born physicist who invented it, but Tuve was the first—in 1932—to put it to
practical use in experiment.
It was essentially a monumental static-
electricity generator, an insulated motor-driven pulley belt that picked up
ions from discharge needles in its metal base, carried them up through an
insulated support cylinder into a smooth metal storage sphere and deposited
them on the sphere.
As ions accumulated the sphere’s voltage increased.
e
voltage could then be discharged as a spark—Van de Graaffs discharging
lightning-bolt sparks have been staples of madscientist movies—or drawn
off to power an accelerator tube.
e new machine was built inside a pear-
shaped pressure tank, as large as the tank of a water tower, that helped
reduce accidental sparking.
When Tuve had first proposed the Van de Graaff to the zoning board of
the prosperous Chevy Chase neighborhood the board had turned him
down.
Smashing atoms smacked of industrial process and the neighborhood
had its property values to consider.
Tuve noted the popularity of the Naval
Observatory, across Connecticut Avenue a few miles west, and rechristened
his project the Atomic Physics Observatory, which it was.
As the APO it
won approval.1058
Roberts and Hafstad chose to work with the APO.
ey had intended to
use the old 1 MV Van de Graaff in the building next door to make neutrons
for their splitter experiment, but that machine’s ion-source filament was
burned out.
Although the APO’s vacuum accelerator tube leaked, finding the
leak looked to be less tedious than replacing the filament.
In fact it needed
two days.
Hafstad went off Friday night on a ski weekend and another young
Tuve protégé, R.
C.
Meyer, took his place.
Roberts’ laboratory notebook entries summarize Saturday’s work:
Sat 4:30 PM 1059
Set up ionization chamber to try to detect
Neutrons from Li + D [accelerated deuterium nuclei bombarding lithium]
...
With uranium lined I.
C.
observed
α’s [approximately] 1-2 mm and occasional 35 mm kicks (Ba + Kr?)
e APO’s target room was a small circular basement accessible down a steel
ladder, a chilly kiva that smelled pleasantly of oil.
As soon as Roberts saw the
“tremendous pulses corresponding to very large energy release” he and
Meyer ran every test they could think of.1060 “We promptly tried the effect of
paraffin (for slow neutrons) and then cadmium to remove the slow
neutrons.
We also tried all the other heavy elements available [to determine
if they would split] and saw the same [i.e., fission] with thorium.
”1061 Having
made that original discovery (Frisch had made it independently in
Copenhagen before them) they stopped to eat.
“I told Tuve aer supper and
he immediately called Bohr and Fermi and they came out Saturday
night.” 1062
Not only Bohr and Fermi came, in heavy, dark, pin-striped three-piece
suits, Fermi swarthy with a day’s growth of beard, but also Tuve; Rosenfeld;
Teller; Erik Bohr, handsome in a heavy overcoat over a decorative Danish
sweater; Gregory Breit, owlish in spectacles; and John A.
Fleming, the
conservative director of the DTM, who had the presence of mind to bring
along a photographer.
All except Teller posed in the target room with Meyer
and Roberts for a historic photograph.
1063 e box of the ionization
chamber in the foreground is stacked with disks of paraffin; Bohr holds the
stub of an aer-dinner cigar; Fermi’s grin reveals the gap between his front
teeth le by a baby tooth he shed late; Roberts looks into the camera weary
but satisfied.
Fermi had been amazed at the ionization pulses on the
oscilloscope and had insisted they check for equipment malfunctions: he
had never seen such pulses in Rome (they were captured by the aluminum
foil Amaldi had wrapped around his uranium to block its alpha
background).1064 Bohr was still fretting.
“I had to stand and look at the first
[sic] experiment,” he wrote Margrethe, “without knowing certainly if Frisch
had done the same experiment and sent a note to Nature”.
1065 Back at Princeton on Sunday he learned from other family letters that Frisch had.
“ere followed,” Roberts concludes, “several days of excitement, press
releases and phone calls.” 1066
Science reporter omas Henry had attended the conference; his story
appeared in the Washington Evening Star on Saturday aernoon.
e
Associated Press picked it up.
Shortened, it earned a place on an inside page
of the Sunday New York Times.
Dunning may have seen it there; he finally
wired Fermi news that morning of the Columbia experiment.
As Herbert
Anderson remembers it, “Fermi...
rushed back to Columbia and
straightaway called me into his office.
My notebook lists the experiments he
felt we should do right away.
e date was January 29, 1939.
”1067 ey had
already agreed, says Anderson, that “I would teach him Americana, and he
would teach me physics.” 1068 Both lessons began in earnest.
e San Francisco Chronicle picked up the wire-service story.
Luis W.
Alvarez, Ernest Lawrence’s tall, ice-blond protégé, a future Nobelist whose
father was a prominent Mayo Clinic physician, read it at Berkeley sitting in a
barber chair in Stevens Union having his hair cut.
“So [I told] the barber to
stop cutting my hair and I got right out of that barber chair and ran as fast as
I could to the Radiation Lab...
where my student Phil Abelson...
had been
[trying to identify] what transuranium elements were produced when
neutrons hit uranium; he was so close to discovering fission that it was
almost pitiful.
”1069 Abelson still remembers the painful moment: “About 9:30
a.m.1070 I heard the sound of running footsteps outside, and immediately
aerward Alvarez burst into the laboratory....
When [he] told me the news,
I almost went numb as I realized that I had come close but had missed a
great discovery....
For nearly 24 hours I remained numb, not functioning
very well.
e next morning I was back to normal with a plan to proceed.”
By the end of the day Abelson found iodine as a decay product of tellurium
from uranium irradiation, another way the nucleus could split (i.e.,
tellurium 52 + zirconium 40 = U 92).
Alvarez wired Gamow for details, learned of the Frisch experiment, then
tracked down Oppenheimer:
I remember telling Robert Oppenheimer that we were going to look for
[ionization pulses from fission] and he said, “at’s impossible” and gave a
lot of theoretical reasons why fission couldn’t really happen.
When I
invited him over to look at the oscilloscope later, when we saw the big
pulses, I would say that in less than fieen minutes Robert had decided
that this was indeed a real effect and...
he had decided that some
neutrons would probably boil off in the reaction, and that you could make
bombs and generate power, all inside of a few minutes....
It was amazing
to see how rapidly his mind worked, and he came to the right
conclusions.1071
e following Saturday Oppenheimer discussed the discovery in a letter to a
friend at Caltech, outlining all the experiments Alvarez and others had
accomplished during the week and speculating on applications:
e U business is unbelievable.
We first saw it in the papers, wired for
more dope, and have had a lot of reports since...
In how many ways does
the U come apart?
At random, as one might guess, or only in certain
ways?
And most of all, are there many neutrons that come off during the
splitting, or from the excited pieces?
If there are, then a 10 cm cube of U
deuteride (one would need the D [deuterium, heavy hydrogen] to slow
them without capture) should be quite something.
1072 What do you
think?
It is I think exciting, not in the rare way of positrons and
mesotrons, but in a good honest practical way.
e next day, in a letter to George Uhlenbeck at Columbia, “quite
something” became “might very well blow itself to hell.” 1073 One of
Oppenheimer’s students, the American theoretical physicist Philip
Morrison, recalls that “when fission was discovered, within perhaps a week
there was on the blackboard in Robert Oppenheimer’s office a drawing—a
very bad, an execrable drawing—of a bomb.
”1074
* * *
Enrico Fermi made similar estimates.
George Uhlenbeck, who shared an
office with him in Pupin Hall, was there one day to overhear him.
Fermi was
standing at his panoramic office window high in the physics tower looking
down the gray winter length of Manhattan Island, its streets alive as always
with vendors and taxis and crowds.
He cupped his hands as if he were
holding a ball.
“A little bomb like that,” he said simply, for once not lightly
mocking, “and it would all disappear.
”1075
PART TWO
A PECULIAR
SOVEREIGNTY
e Manhattan District bore no relation to the industrial or social life of our country; it was a separate
state, with its own airplanes and its own factories and its thousands of secrets.
It had a peculiar sovereignty, one that could bring about the end, peacefully or violently, of all other sovereignties.
Herbert S.
Marks
We must be curious to learn how such a set of objects—hundreds of power plants, thousands of bombs,
tens of thousands of people massed in national establishments—can be traced back to a few people sitting
at laboratory benches discussing the peculiar behavior of one type of atom.
Spencer R.
Weart
10
Neutrons
At the end of January 1939, still ill with a feverish cold that had laid him low
for more than a week but determined to prevent information on the
possibility of a chain reaction in uranium from reaching physicists in Nazi
Germany, Leo Szilard raised himself from his bed in the King’s Crown Hotel
on West 116th Street in Manhattan and went out into the New York winter
to take counsel of his friend Isador Isaac Rabi.1076 Rabi, no taller than
Szilard but always a trimmer and cooler man, who would be the 1944 Nobel
laureate in physics, was born in Galicia in 1898 and emigrated to the United
States with his family as a small child.
Yiddish had been his first language; he
grew up on New York’s Lower East Side, where his father worked in a
sweatshop making women’s blouses until he accumulated enough savings to
open a grocery store.
Because his family was Orthodox and fundamentalist
in its Judaism, Rabi had not known that the earth revolved around the sun
until he read it in a library book.
A frightening vision of the vast yellow face
of the rising moon seen as a child down a New York street had begun his
turn toward science, as had his childhood reading of the cosmological first
verses of the Book of Genesis.
He was a man of abrupt and honest bluntness
who did not easily tolerate fools.
One reason for his impatience was
certainly that it guarded from harm his deeply emotional commitment to
science: he thought physics “infinite,” he told a biographer in late middle
age, and he was disappointed that young physicists of that later day, intent
on technique, seemed to miss what he had found, “the mystery of it: how
very different it is from what you can see, and how profound nature is.” 1077,
1078
Szilard learned from Rabi that Enrico Fermi had discussed the possibility
of a chain reaction in his public presentation at the Fih Washington
Conference on eoretical Physics that had met the week before.
1079 Szilard
adjourned to Fermi’s office but did not find him there.
He went back to Rabi
and asked him to talk to Fermi “and say that these things ought to be kept
secret.” Rabi agreed and Szilard returned to his sickbed.
He was recovering; a day or two later he again sought Rabi out:
I said to him: “Did you talk to Fermi?” Rabi said, “Yes, I did.” I said,
“What did Fermi say?” Rabi said, “Fermi said ‘Nuts!’ ” So I said, “Why did
he say ‘Nuts!’?” and Rabi said, “Well, I don’t know, but he is in and we can
ask him.” So we went over to Fermi’s office, and Rabi said to Fermi, “Look,
Fermi, I told you what Szilard thought and you said ‘Nuts!’ and Szilard
wants to know why you said ‘Nuts!’ ” So Fermi said, “Well...
there is the
remote possibility that neutrons may be emitted in the fission of uranium
and then of course perhaps a chain reaction can be made.” Rabi said,
“What do you mean by ‘remote possibility’?” and Fermi said, “Well, ten
per cent.” Rabi said, “Ten per cent is not a remote possibility if it means
that we may die of it.
If I have pneumonia and the doctor tells me that
there is a remote possibility that I might die, and it’s ten percent, I get
excited about it.” 1080
But despite Fermi’s facility with American slang and Rabi’s with probabilities
Fermi and Szilard were unable to agree.
For the time being they le the
discussion there.
Fermi was not misleading Szilard.
It was easy to estimate the explosive
force of a quantity of uranium, as Fermi would do standing at his office
window overlooking Manhattan, if fission proceeded automatically from
mere assembly of the material; even journalists had managed that simple
calculation.
But such obviously was not the case for uranium in its natural
form, or the substance would long ago have ceased to exist on earth.
However energetically interesting a reaction, fission by itself was merely a
laboratory curiosity.
Only if it released secondary neutrons, and those in
sufficient quantity to initiate and sustain a chain reaction, would it serve for
anything more.
“Nothing known then,” writes Herbert Anderson, Fermi’s
young partner in experiment, “guaranteed the emission of neutrons.
Neutron emission had to be observed experimentally and measured
quantitatively.” 1081 No such work had yet been done.
It was, in fact, the new
work Fermi had proposed to Anderson immediately upon returning from
Washington.
Which meant to Fermi that talk of developing fission into a
weapon of war was absurdly premature.
Many years later Szilard succinctly summed up the difference between his
position and Fermi’s.
“From the very beginning the line was drawn,” he said.
“...
Fermi thought that the conservative thing was to play down the
possibility that [a chain reaction] may happen, and I thought the
conservative thing was to assume that it would happen and take all the
necessary precautions.” 1082
Once he was well again Szilard had catching up to do.
He cabled Oxford to
ship him the cylinder of beryllium he had le behind at the Clarendon when
he came to the United States, preliminary to mounting a neutron-emission
experiment of his own.
At Lewis Strauss’s request he spent a day with the
financier discussing the possible consequences of fission, which included,
Strauss notes wistfully in his memoirs, making “the performance of our
surge generator in Pasadena insignificant.1083 e device had just been
completed.” 1084 e surge generator in which he had invested some tens of
thousands of dollars had been cut down to size.
e Strausses were
scheduled to leave that evening by overnight train for a Palm Beach
vacation; Szilard rode along as far as Washington to continue the discussion.
He was massaging his patron: he needed to rent radium to combine with his
beryllium to make a neutron source and hoped Strauss might be persuaded
to support the expense.
Arriving late at Union Station in Washington, Szilard called the Edward
Tellers.
ey were still recovering from the work of hosting the Washington
Conference.
Mici Teller protested the surprise visit, her husband remembers:
“No!
We are both much too tired.
He must go to a hotel.” ey met Szilard
anyway, whereupon to Teller’s surprise Mici invited their countryman to stay
with them:1085
We drove to our home, and I showed Szilard to his room.
He felt the bed
suspiciously, then turned to me suddenly and said: “Is there a hotel
nearby?” ere was, and he continued: “Good!
I have just remembered
sleeping in this bed before.
It is much too hard.”
But before he le, he sat on the edge of the hard bed and talked
excitedly: “You heard Bohr on fission?”
“Yes,” I replied.
Szilard continued: “You know what that means!”
What it meant to Szilard, Teller remembers, was that “Hitler’s success could
depend on it.”
e next day Szilard discussed his plan for voluntary secrecy with Teller,
then entrained for Princeton to pursue the same subject with Eugene
Wigner, who was still drydocked in the infirmary with jaundice.
Szilard was
thus present in Princeton when yet another momentous insight struck Niels
Bohr.
* * *
Bohr and Léon Rosenfeld were staying at the Nassau Club, the Princeton
faculty center.
On Sunday, February 5, George Placzek joined them at
breakfast in the club dining room.
e Bohemian theoretician had arrived in
Princeton from Copenhagen the night before, another refugee from Nazi
persecution.
Talk turned to fission.
“It is a relief that we are now rid of those
transuranians,” Rosenfeld remembers Bohr saying, referring to the
confusing radioactivities Hahn, Meitner and Strassmann had found in the
late 1930s that Bohr assumed could now be attributed to existing lighter
elements—barium, lanthanum and the many other fission products
researchers were beginning to identify.
Placzek was skeptical.
“e situation is more confused than ever,” he told
Bohr.1086 He began then to specify the sources of confusion.
He was directly
challenging the relevance of Bohr’s liquid-drop model of the nucleus.
e
Danish laureate paid attention.
Physicists use a convenient measurement they call a “cross section” to
indicate the probability that a particular nuclear reaction will or will not
happen.
e theoretical physicist Rudolf Peierls once explained the
measurement with this analogy:
For example, if I throw a ball at a glass window one square foot in area,
there may be one chance in ten that the window will break, and nine
chances in ten that the ball will just bounce.
In the physicists’ language,
this particular window, for a ball thrown in this particular way, has a
“disintegration cross-section” of 1/10 square foot and an “elastic cross-
section” of 9/10 square foot.1087
Cross sections can be measured for many different nuclear reactions, and
they are expressed not in square feet but in minute fractions of square
centimeters, customarily 10–24, because the diminutive nucleus is the target
window of Peierls’ analogy.
e cross section that concerned Placzek in his
discussion with Bohr was the capture cross section: the probability that a
nucleus will capture an approaching neutron.
In terms of Peierls’ analogy,
the capture cross section measures the chance that the window might be
open when the ball arrives and might therefore admit the ball into the living
room.
Nuclei capture neutrons of certain energies more frequently than they
capture neutrons of other energies.
ey are naturally tuned, so to speak, to
certain specific energy levels—as if Peierls’ window opened more easily to
balls thrown at only certain speeds.
is phenomenon is known as
resonance.
e confusion Placzek delighted in reporting concerned a
resonance in the capture cross sections of uranium and thorium.
Placzek pointed out that uranium and thorium both exhibit a capture
resonance for neutrons with medium-range energies of about 25 electron
volts.
at meant, first of all, that although fission was one behavior uranium
could exhibit under neutron bombardment, capture and subsequent
transmutation continued to be another.
Bohr was not ever to be rid of those
inconvenient “transuranians.” Some of them were real.
If a neutron penetrated a uranium nucleus, for example, the result might
be fission.
But if the neutron happened to be traveling at the appropriate
energy when it penetrated—somewhere around 25 eV—the nucleus would
probably capture it without fissioning.
Beta decay would follow, increasing
the nuclear charge by one unit; the result should be a new, as-yet-unnamed
transuranic element of atomic number 93.
at was one of Placzek’s points.
It would prove in time to be crucial.
e other source of confusion was more straightforward.
It was also more
immediately relevant to the question of how to harness nuclear energy.
It
concerned differences between uranium and thorium.
orium, element 90, a so, heavy, lustrous, silver-white metal, was first
isolated by the celebrated Swedish chemist Jons Jakob Berzelius in 1828.
Berzelius named the new element aer or, the Norse god of thunder.
Its
oxide found commercial use beginning in the late nineteenth century as the
primary component of the fragile woven mantles of gas lanterns: heat
incandesces it a brilliant white.
Because it is mildly radioactive, and
radioactivity was once considered tonic, thorium was also for some years
incorporated into a popular German toothpaste, Doramad.
Auer, the
company that made German gas mantles, also made the toothpaste.
Hahn,
Meitner and Strassmann, the Joliot-Curies and others had regularly studied
thorium alongside uranium.
Its behavior was oen similar.
Otto Frisch had
first demonstrated that it fissioned.
He bombarded it next aer uranium in
the course of his January experiment in Copenhagen, the experiment he had
discussed with Bohr aer he returned from Kungälv and Bohr had worked
so hard in the United States to protect.
Frisch was then also the first to notice that the fission characteristics of
thorium differed from those of uranium.
orium did not respond to the
magic of paraffin; it was unaffected by slow neutrons.
Richard B.
Roberts
and his colleagues at the Department of Terrestrial Magnetism of the
Carnegie Institution of Washington had just independently confirmed and
extended Frisch’s findings.
With their 5 million volt Van de Graaff they
could generate neutrons of several different, known energies.
Continuing
their experiments aer their Saturday-night show for the Washington
Conference group, they had compared uranium and thorium fission
responses at varying energies as Frisch with his single neutron source could
not.
ey found to their surprise (Frisch’s paper had not yet appeared in
Nature) that while both uranium and thorium fissioned under
bombardment by fast neutrons, only uranium fissioned under
bombardment by slow neutrons.
Some energy between 0.5 MeV and 2.5
MeV marked a lower threshold for fast-neutron fission for both elements.
(Bohr and John Wheeler, beginning work at Princeton on fission theory, had
estimated the threshold energy to be about 1 MeV.) e slow neutrons that
also fissioned uranium were effective at far lower energies.
“From these
comparisons,” the DTM group concluded in a February paper, “it appears
that the uranium fissions are produced by different processes for fast and
slow neutrons.
”1088
Why, Placzek now prodded Bohr, should both uranium and thorium have
similar capture resonances and similar fast-neutron thresholds but different
responses to slow neutrons?
If the liquid-drop model had any validity at all,
the difference made no sense.
Bohr abruptly saw why and was struck dumb.
Not to lose what he had
only barely grasped, oblivious to courtesy, he pushed back his chair and
strode from the room and from the club.
Rosenfeld hurried to follow.
“Taking a hasty leave of Placzek, I joined Bohr, who was walking silently,
lost in deep meditation, which I was careful not to disturb.” e two men
tramped speechless through the snow across the Princeton campus to Fine
Hall, the Neo-Gothic brick building where the Institute for Advanced Study
was then lodged.
ey went in to Bohr’s office, borrowed from Albert
Einstein.
It was spacious, with leaded windows, a fireplace, a large
blackboard, an Oriental rug to warm the floor.1089 No peripatetic like Bohr,
Einstein had judged it too large and moved into a small secretarial annex
nearby.
“As soon as we entered the office,” Rosenfeld remembers, “[Bohr] rushed
to the blackboard, telling me: ‘Now listen: I have it all.’ And he started—
again without uttering a word—drawing graphs on the blackboard.”
e first graph Bohr drew looked like this:
e horizontal axis plotted neutron energy le to right—low to high, slow to
fast.
e vertical axis charted cross sections—the probability of a particular
nuclear reaction—and served a double purpose.
e lazy S that filled most
of the frame represented thorium’s cross section for capture at different
neutron energies, the steep central peak demonstrating the 25 eV resonance
in the middle range.
e tail that waved from the horizontal axis on the
right side represented a different thorium cross section: its cross section for
fission beginning at that high 1 MeV threshold.
What Bohr had drawn was
thus a visualization of thorium’s changing response to bombardment by
neutrons of increasing energy.
Bohr moved to the next section of blackboard and drew a second graph.
He labeled it with the mass number of the isotope most plentiful in natural
uranium.
“He wrote the mass number 238 with very large figures,” Rosenfeld
says; “he broke several pieces of chalk in the process.
”1090 Bohr’s urgency
marked the point of his insight.
e second graph looked exactly like the
first:
But a third graph was coming.
Francis Aston had found only U238 when he first passed uranium
through his mass spectrograph at the Cavendish.
In 1935, using a more
powerful instrument, physicist Arthur Jeffrey Dempster of the University of
Chicago detected a second, lighter isotope.
“It was found,” Dempster
announced in a lecture, “that a few seconds’ exposure was sufficient for the
main component at 238 reported by Dr.
Aston, but on long exposures a faint
companion of mass number 235 was also present.
”1091 ree years later a
gied Harvard postdoctoral fellow named Alfred Otto Carl Nier, the son of
working-class German emigrants to Minnesota, measured the ratio of U235
to U238 in natural uranium as 1:139, which meant that U235 was present to
the extent of about 0.7 percent.1092 By contrast, thorium in its natural form
is essentially all one isotope, 232.
And that natural difference in the
composition of the two elements was the clue that set Bohr off.
He drew his
third graph.
It depicted one cross section, not two:
Having made a hard copy of his abrupt vision, Bohr was finally ready to
explain himself.
Both thorium and U238 could be expected on theoretical grounds to
behave similarly, he pointed out to Rosenfeld: to fission only with fast
neutrons above 1 MeV.
And it seemed that they did.
at le U235.
It
followed as a matter of logic, Bohr said triumphantly, that U235 must be
responsible for slow-neutron fission.
Such was his essential insight.
He went on to explore the subtle energetics of the several reactions.
orium was lighter than U235, U238 heavier, but the middle isotope
differed more significantly in another important regard.
When 232
absorbed a neutron it became a nucleus of odd mass number, 233.
When
U238 absorbed a neutron it also became a nucleus of odd mass number,
U239.
But when U235 absorbed a neutron it became a nucleus of even mass
number, U236.
And the vicissitudes of nuclear rearrangement are such, as
Fermi would explain one day in a lecture, that “changing from an odd
number of neutrons to an even number of neutrons released one or two
MeV.
”1093 Which meant that U235 had an inherent energetic advantage over
its two competitors: it accrued energy toward fission simply by virtue of its
change of mass; they did not.
Lise Meitner and Otto Frisch had realized in Kungälv that a certain
amount of energy was necessary to agitate the nucleus to fission, but they
had not considered in detail the energetics of that input.
ey were
distracted by the enormous 200 MeV output.
In fact, the uranium nucleus
required an input of about 6 MeV to fission.
at much energy was
necessary to roil the nucleus to the point where it elongated and broke apart.
e absorption of any neutron, regardless of its velocity, made available a
binding energy of about 5.3 MeV.
But that le U238 about 1 MeV short,
which is why it needed fast neutrons of at least that threshold energy before
it could fission.
U235 also earned 5.3 MeV when it absorbed a neutron.
But it won Fermi’s
“one or two MeV” in addition simply by adjusting from an odd to an even
mass.
at put its total above 6 MeV.
So any neutron at all would fission
U235—slow, fast or in between.
Which was what Bohr’s third graph
demonstrated: the probably continuous fission cross section of U235.
From
slow neutrons on the le only a fraction of an electron volt above zero
energy, to fast neutrons on the right above 1 MeV that would also fission
U238, any neutron an atom of U235 encountered would agitate it to fission.
Natural uranium masked U235’s continuous fissibility; the more abundant
U238 captured most of the neutrons.
Only by slowing the neutrons with
paraffin below the U238 capture resonance at 25 eV had experimenters like
Hahn, Strassmann and Frisch been able to coax the highly fissionable U235
out of hiding.
In a burst of insight Bohr had answered Placzek’s objections
and replenished his liquid drop.
In January Bohr had produced a 700-word paper in three days to protect
his European colleagues’ priorities.
Now, in his eagerness to spread the news
of U235’s special role in fission, he produced an 1,800-word paper in two
days, mailing it to the Physical Review on February 7.
“Resonance in
uranium and thorium disintegrations and the phenomenon of nuclear
fission” was nevertheless written with care, more care than it received in the
reading.
1094 Everyone understood its basic hypothesis—that U235, not
U238, is responsible for slow-neutron fission in uranium—though not
everyone concurred without the confirmation of experiment.
But probably
because, as Fermi recalled, isotopes at that time “were considered almost
magically inseparable,” everyone overlooked its further implications.1095
Szilard explained to Lewis Strauss that month that “slow neutrons seem to
split a uranium isotope which is present in an abundance of about 1% in
uranium.” 1096 Richard Roberts at the DTM, in a 1940 dra report of
considerable significance, asserted that “Bohr...
ascribed the [slow]
neutron reaction to U235 and the fast neutron reaction to U238.” 1097
Roberts’ misstatement was probably no more than a rough first
approximation that he would have corrected in a polished report.
Szilard’s
and Roberts’ comments illustrate, however, that the slow-neutron fission of
U235 preoccupied the physicists at first to the exclusion of a more ominous
potentiality.
Bohr acknowledged it indirectly in his paper for the Physical Review.
e
slow-neutron fission of U235 occupied the foreground of his discussion
because it explained the puzzling difference between uranium and thorium.
But Bohr also considered U235’s behavior under fast-neutron
bombardment.
“For fast neutrons,” he wrote near the end of the paper, “...
because of the scarcity of the isotope concerned, the fission yields will be
much smaller than those obtained from neutron impacts on the abundant
isotope.
”1098 e statement implies but does not ask a pregnant question:
what would the yields be for fast neutrons if U235 could be separated from
U238?
* * *
e latest incarnation of Orso Corbino’s garden fish pond in Rome was a
tank of water three feet wide and three feet deep that Fermi and Anderson
set up that winter in the basement of Pupin Hall.
1099 ey planned to insert
a radon-beryllium neutron source into the center of a five-inch spherical
bulb and suspend the bulb in the middle of the tank.
Neutrons from the
beryllium would then diffuse through the surrounding water, which would
slow them down.
e neutrons would induce a characteristic 44-second
half-life in strips of rhodium foil, Fermi’s favorite neutron detector, set at
various distances away from the bulb.
Once he established a baseline of
neutron activity using the Rn + Be source alone, Fermi intended to pack
uranium oxide into the bulb around the source and make a second series of
measurements.
If more neutrons turned up in the water tank with uranium
than without, he could deduce that uranium produced secondary neutrons
when it fissioned and could roughly estimate their number.
One neutron out
for each neutron in was not enough to sustain a chain reaction, since
inevitably some would be captured and others dri away: it needed
something more than one secondary for each primary, preferably at least
two.
Upstairs on the seventh floor Szilard discovered a different experiment in
progress.
Walter Zinn, a tall, blond Canadian postdoctoral research associate
who taught at City College, was bombarding uranium with 2.5 MeV
neutrons from a small accelerator.
He had reasoned in terms of neutron
energy rather than quantity; he was trying to demonstrate secondary
neutron production by looking for neutrons faster than the 2.5 MeV’s he
supplied.
So far he had managed only inconclusive results.
“Szilard watched my experiment with great interest,” Zinn recalls, “and
then suggested that perhaps it would be more successful if lower energy
neutrons were available.
I said, ‘at’s fine, but where do you get them?’ Leo
said, ‘Just leave it to me, I’ll get them.’ ” 1100
Szilard meant to help Zinn, but he also coveted Zinn’s ionization chamber.
“All we needed to do,” he said later, “was to get a gram of radium, get a block
of beryllium, expose a piece of uranium to the neutrons which come from
the beryllium, and then see by means of the ionization chamber which Zinn
had built whether fast neutrons were emitted in the process.
Such an
experiment need not take more than an hour or two to perform, once the
equipment has been built and if you have the neutron source.
1101 But of
course we had no radium.”
e problem was still money.
e Radium Chemical Company of New
York and Chicago, a subsidiary of the Union Miniére du Haut-Katanga of
Belgium, the dominant source of world radium supplies, was willing to rent
a gram of radium for a minimum of three months for $125 a month.
Szilard
wrote Lewis Strauss at his Virginia farm on February 13 “to see whether you
could sanction the expenditures” and presciently briefed the financier on the
meaning of the latest developments.
e letter’s crucial paragraph addresses
Bohr’s new hypothesis that U235 is responsible for slow-neutron fission in
natural uranium:1102
If this isotope could be used for maintaining chain reactions, it would
have to be separated from the bulk of uranium.
is, no doubt, would be
done if necessary, but it might take five to ten years before it can be done
on a technical scale.
Should small scale experiments show that the
thorium and the bulk of uranium would not work, but the rare isotope of
uranium would, we would have the task immediately to attack the
question of concentrating the rare isotope of uranium.1
Strauss’s surge-generator losses had inoculated him against further
investment in the nuclear enterprise.
He wanted to know, Szilard says, “just
how sure I was that this would work.” Since Szilard could offer no
guarantees, Strauss offered no support.
Szilard turned then to Benjamin
Liebowitz.
“He was not poor but he was not exactly wealthy....
I told him
what this was all about, and he said, ‘How much money do you need?’ I said,
‘Well, I’d like to borrow $2,000.’ He took out his checkbook, he wrote out a
check, I cashed the check, I rented the...
radium, and in the meantime the
beryllium block arrived from England.
”1103
e cylinder of beryllium, which Walter Zinn thought “a strange and
unique object” and took for proof of Szilard’s magic ways, arrived on
February 18.
1104, 1105 e same day Szilard heard from Teller about significant work in Washington at the DTM.
Richard Roberts and R.
C.
Meyer were preparing a letter to the Physical Review reporting the discovery
of delayed neutrons from fission.
ese were not the instantaneous
secondary neutrons the Columbia researchers were seeking, but they did
confirm that the fission fragments had neutrons to spare and would give
them up spontaneously.
e general excitement Teller found at the busy DTM laboratories
impressed him more:
As soon as I began taking interest in uranium, sharp discussion started on
the practical significance.
Tuve, Hafstad, and Roberts are entirely aware of
what is involved.
ey also know of Fermi’s experiments.
Of course, I
didn’t say anything.
e above-mentioned letter [to the Physical Review]
cannot cause any harm....1109
I do not know their detailed plans, but I believe that urgent action [to
maintain secrecy] is required.
Very many people have discovered already
what is involved.
ose in Washington would like to persuade the
Carnegie Institution that it should provide more money for U-research in
view of the practical significance of the matter....
But right now this has
no reality unless the [Carnegie] leadership becomes more interested than
it has been so far....
I repeat that there is a chain-reaction mood in Washington.
I only had
to say “uranium” and then could listen for two hours to their thoughts.
e president of the Carnegie Institution was a New England Yankee, the
grandson of two sea captains, an electrical engineer, inventor and former
dean of the school of engineering at the Massachusetts Institute of
Technology named Vannevar Bush.
If Bush was initially less willing to invest
in chain-reaction experiments than Teller would have liked him to be, he
kept good company; neither Ernest Lawrence at Berkeley nor Otto Hahn in
Dahlem nor Lise Meitner, visiting Copenhagen that February to work with
Otto Frisch, chose to pursue moonshine.
Only Columbia and Paris mounted
early experiments, though the DTM would soon follow the Columbia lead.
Frédéric Joliot and two colleagues, a cultivated Austrian named Hans von
Halban and a huge, keen Russian named Lew Kowarski, began an
experiment similar to Fermi’s the last week in February to identify
secondary neutrons from fission.
ey also used a tank of water with a
central neutron source but dissolved their uranium in the water rather than
packing it around the source.
More important to their priority of research,
they had immediate access to the Radium Institute’s ample radium supply.
Because Fermi’s neutron source relied on radon rather than radium it
induced an ambiguity into his experiment that Szilard caught and called to
his attention: radon ejected much faster neutrons from beryllium than did
radium; at least part of any increase in neutrons Fermi found in his tank
might therefore result not from fission but from another, competing reaction
in beryllium.
Fermi thought the ambiguity trivial, but agreed, as Zinn had
before, to repeat the experiment using a radium-beryllium source.
1110
Szilard generously offered his.
But the radium to energize it was not yet in
hand; Szilard was still negotiating its rental because his lack of official
affiliation made the Radium Chemical Company nervous.
He got his radium, two grams sealed in a small brass capsule, early in
March, aer he arranged admission to the Columbia laboratories for three
months as a guest researcher.
He and Zinn immediately set up their
experiment.
ey made an ingenious nest, like Chinese boxes, of its various
components: a large cake of paraffin wax, the beryllium cylinder set at the
bottom of a blind hole in the paraffin, the radium capsule fitted into the
beryllium cylinder; resting on the beryllium, inside the paraffin, a box lined
with neutron-absorbing cadmium filled with uranium oxide; pushed into
that box, but shielded from the radium’s gamma radiation by a lead plug, the
ionization tube itself, which connected to an oscilloscope.
With this
arrangement, says Szilard, they could measure the flux of neutrons from the
uranium with and without the cadmium shield:
Everything was ready and all we had to do was to turn a switch, lean back,
and watch the screen of a television tube.
If flashes of light appeared on
the screen, that would mean that neutrons were emitted in the fission
process of uranium and this in turn would mean that the large-scale
liberation of atomic energy was just around the corner.
We turned the
switch and saw the flashes.
We watched them for a little while and then we
switched everything off and went home.
1111
ey had made a rough estimate of neutron production: “We find the
number of neutrons emitted per fission to be about two.” 1112 With radium
available merely by picking up the phone, the French team a week earlier
had found “more than one neutron...
produced for each neutron
absorbed.” 1113 Fermi and Anderson estimated “a yield of about two neutrons
per each neutron captured.
”1114 Szilard immediately alerted Wigner and
Teller.
Teller remembers the moment well:
I was at my piano, attempting with the collaboration of a friend and his
violin to make Mozart sound like Mozart, when the telephone rang.
It was
Szilard, calling from New York.
He spoke to me in Hungarian, and he said
only one thing: “I have found the neutrons.
”1115
Szilard also wired Lewis Strauss:
PERFORMED TODAY PROPOSED EXPERIMENT WITH BERYLLIUM BLOCK WITH
STRIKING RESULT.
VERY LARGE NEUTRON EMISSION FOUND.
ESTIMATE CHANCES
FOR REACTION NOW ABOVE 50%.1116
Szilard had known what the neutrons would mean since the day he crossed
the street in Bloomsbury: the shape of things to come.
“at night,” he
recalled later, “there was very little doubt in my mind that the world was
headed for grief.” 1117
* * *
ough he was still recovering from jaundice, Eugene Wigner responded
vigorously to Szilard’s disturbing news while a storm of betrayal broke over
Central Europe.
Hitler ordered the President and the Foreign Minister of
Czechoslovakia to Berlin on March 14 and threatened to bomb Prague to
rubble unless they surrendered their country.
With the Nazi leader’s
encouragement the Slovaks formally seceded from the republic that day.
Ruthenia, Czechoslovakia’s narrow eastern extension along the Carpathians,
also claimed independence as Carpatho-Ukraine, an exercise in grave-
robbing abruptly terminated the following morning when the fascist
Hungary of Admiral Horthy invaded the new nation with German
endorsement.
Hitler flew in triumph to Prague.
On March 16 he decreed
what was le of Czechoslovakia—Bohemia and Moravia—to be a German
protectorate.
e country that France and Great Britain had abandoned at
Munich was partitioned without resistance.
Wigner caught the train to New York.
On the morning of March 16 he
met with Szilard, Fermi and George Pegram in Pegram’s office.
Since at least
the end of January Szilard had been promoting a new version of his Bund—
he called it the Association for Scientific Collaboration—to monitor
research, collect and disburse funds and maintain secrecy, a civilian
organization that might guide the development of atomic energy.
He had
discussed it with Lewis Strauss on the train to Washington, with Teller aer
the night of the hard bed, with Wigner in Princeton the weekend Bohr drew
his graphs.
As far as Wigner was concerned, the time for such amateurism
was over.
He “strongly appealed to us,” says Szilard, “immediately to inform
the United States government of these discoveries.” 1118 It was “such a serious
business that we could not assume responsibility for handling it.” 1119
At sixty-three George Braxton Pegram was a generation older than the
two Hungarians and the Italian who debated in his office that morning.
1120
A South Carolinian who had earned his Ph.D.
from Columbia in 1903
working with thorium, he had studied under Max Planck at the University
of Berlin and corresponded with Ernest Rutherford when Rutherford was
still progressing in fruitful exile at McGill.
Pegram was tall and athletic, a
champion at tennis well into his sixties, a canoeist when young who enjoyed
paddling and sailing an eighteen-foot sponson around Manhattan Island.
His interest in radioactivity may have been aroused by his father, a
chemistry professor; “probably the most important problem before the
physicist today,” the senior Pegram told the North Carolina Academy of
Sciences in 1911, “is that of making the enormous energy [within the atom]
available for the world’s work.
”1121 e next year, as an associate professor of
physics at Columbia, Pegram had written Albert Einstein encouraging him
to come to New York to lecture on relativity theory.
Pegram had brought
Rabi and Fermi to Columbia, building the university’s international
reputation for nuclear research.
He was gray now, with thinning hair,
wirerimmed glasses, protuberant ears, a strong, square, wide-chinned jaw.
Radioactivity intrigued him still, but a university dean’s well-worn
conservatism counseled him to caution.
He knew someone in Washington, he told Wigner: Charles Edison,
Undersecretary of the Navy.
Wigner insisted Pegram immediately call the
man.
Pegram was willing to do so, but first the group should discuss
logistics.
Who would carry the news?
Fermi was traveling to Washington
that aernoon to lecture in the evening to a group of physicists; he could
meet with the Navy the next day.
His Nobel Prize should give him
exceptional credibility.
Pegram called Washington.
Edison was unavailable;
his office directed Pegram to Admiral Stanford C.
Hooper, technical
assistant to the Chief of Naval Operations.
Hooper agreed to hear Fermi out.
Pegram’s call was the first direct contact between the physicists of nuclear
fission and the United States government.
e next topic on the morning’s agenda was secrecy.
Fermi and Szilard
had both written reports on their secondary-neutron experiments and were
ready to send them to the Physical Review.
With Pegram’s concurrence they
decided to go ahead and mail the reports to the Review, to establish priority,
but to ask the editor to delay publishing them until the secrecy issue could
be resolved.
Both papers went off that day.
Pegram prepared a letter of introduction for Fermi to carry along to his
appointment.
It stated a hesitant case dense with hypotheticals:
Experiments in the physics laboratory at Columbia University reveal that
conditions may be found under which the chemical element uranium may
be able to liberate its large excess of atomic energy, and that this might
mean the possibility that uranium might be used as an explosive that
would liberate a million times as much energy per pound as any known
explosive.
My own feeling is that the probabilities are against this, but my
colleagues and I think that the bare possibility should not be
disregarded.
1122
us lightly armed, Fermi departed to engage the Navy.
e debate was hardly ended, nor Wigner’s long day done.
He returned to
Princeton with Szilard in tow for an important meeting with Niels Bohr.
It
had been planned in advance; John Wheeler and Léon Rosenfeld would
attend and Teller was making a special trip up from Washington.
If Bohr
could be convinced to swing his prestige behind secrecy, the campaign to
isolate German nuclear physics research might work.
ey met in the evening in Wigner’s office.
“Szilard outlined the Columbia
data,” Wheeler reports, “and the preliminary indications from it that at least
two secondary neutrons emerge from each neutron-induced fission.
Did this
not mean that a nuclear explosive was certainly possible?” Not necessarily,
Bohr countered.1123 “We tried to convince him,” Teller writes, “that we
should go ahead with fission research but we should not publish the results.
We should keep the results secret, lest the Nazis learn of them and produce
nuclear explosions first.
Bohr insisted that we would never succeed in
producing nuclear energy and he also insisted that secrecy must never be
introduced into physics.” 1124
Bohr’s skepticism, says Wheeler, concerned “the enormous difficulty of
separating the necessary quantities of U235.
”1125 Fermi noted in a later
lecture that “it was not very clear [in 1939] that the job of separating large
amounts of uranium 235 was one that could be taken seriously.
”1126 At the
Princeton meeting, Teller remembers, Bohr insisted that “it can never be
done unless you turn the United States into one huge factory.
”1127
More crucial for Bohr was the issue of secrecy.
He had worked for decades
to shape physics into an international community, a model within its limited
franchise of what a peaceful, politically united world might be.
Openness
was its fragile, essential charter, an operational necessity, as freedom of
speech is an operational necessity to a democracy.
Complete openness
enforced absolute honesty: the scientist reported all his results, favorable and
unfavorable, where all could read them, making possible the ongoing
correction of error.
Secrecy would revoke that charter and subordinate
science as a political system—Polanyi’s “republic”—to the anarchic
competition of the nation-states.
No one was more anguished than Bohr by
the menace of Nazi Germany; Laura Fermi remembers of this period, “two
months aer his landing in the United States,” that “he spoke about the
doom of Europe in increasingly apocalyptic terms, and his face was that of a
man haunted by one idea.
”1128 If U235 could be separated easily from U238,
that misfortune might be cause for temporary compromise with principle in
the interest of survival.
Bohr thought the technology looked not even
remotely accessible.
e meeting dragged on inconclusively past midnight.
e next aernoon Fermi turned up at the Navy Department on
Constitution Avenue for his appointment with Admiral Hooper.
He had
probably planned a conservative presentation.
e contempt of the desk
officer who went in to announce him to the admiral encouraged that
approach.
“ere’s a wop outside,” Fermi overheard the man say.
1129 So
much for the authority of the Nobel Prize.
In what Lewis Strauss, by now a Navy volunteer, calls “a ramshackle old
board room” Hooper assembled an audience of naval officers, officers from
the Army’s Bureau of Ordnance and two civilian scientists attached to the
Naval Research Laboratory.
1130 One of the civilians, a bluff physicist named
Ross Gunn, had watched Richard Roberts demonstrate fission in the target
room of the 5 MV Van de Graaff at the DTM not long aer Fermi passed
through at the time of the Fih Washington Conference.
Gunn worked on
submarine propulsion; he was eager to learn more about an energy source
that burned no oxygen.
Fermi led his auditors through an hour of neutron physics.
If the notes of
one of the participants, a naval officer, are comprehensive, Fermi
emphasized his water-tank measurements rather than Szilard’s more direct
ionization-chamber work.
New experiments in preparation might confirm a
chain reaction, Fermi explained.
e problem then would be to assemble a
sufficiently large mass of uranium to capture and use the secondary
neutrons before they escaped through the surface of the material.
e officer taking notes interrupted.
1131 What might be the size of this
mass?
Would it fit into the breech of a gun?
Rather than look at physics down a gun barrel Fermi withdrew to the
ultramundane.
It might turn out to be the size of a small star, he said,
smiling and knowing better.
Neutrons diffusing through a tank of water: it was all too vague.
Except to
alert Ross Gunn, the meeting came to nothing.
“Enrico himself...
doubted
the relevance of his predictions,” says Laura Fermi.1132 e Navy reported
itself interested in maintaining contact; representatives would undoubtedly
visit the Columbia premises.
Fermi smelled the condescension and cooled.
March 17 was a Friday; Szilard traveled down to Washington from
Princeton with Teller; Fermi stayed the weekend.
ey got together, reports
Szilard, “to discuss whether or not these things”—the Physical Review papers
—“should be published.
Both Teller and I thought that they should not.
Fermi thought that they should.
But aer a long discussion, Fermi took the
position that aer all this was a democracy; if the majority was against
publication, he would abide by the wish of the majority.
”1133 Within a day or
two the issue became moot.
e group learned of the Joliot/von
Halban/Kowarski paper, published in Nature on March 18.1134 “From that
moment on,” Szilard notes, “Fermi was adamant that withholding
publication made no sense.
”1135
e following month, on April 22, Joliot, von Halban and Kowarski
published a second paper in Nature concerning secondary neutrons.
1136 is
one, “Number of neutrons liberated in the nuclear fission of uranium,” rang
bells.
Calculating on the basis of the experiment previously reported, the
French team found 3.5 secondary neutrons per fission.
“e interest of the
phenomenon discussed here as a means of producing a chain of nuclear
reactions,” the three men wrote, “was already mentioned in our previous
letter.” Now they concluded that if a sufficient amount of uranium were
immersed in a suitable moderator, “the fission chain will perpetuate itself
and break up only aer reaching the walls limiting the medium.
Our
experimental results show that this condition will most probably be
satisfied.” 1137 at is, uranium would most probably chain-react.
Joliot’s was an authoritative voice.
G.
P.
omson, J.J.’s son, who was
professor of physics at Imperial College, London, heard it.
“I began to
consider carrying out certain experiments with uranium,” he told a
correspondent later.
“What I had in mind was something rather more than a
piece of pure research, for at the back of my thoughts there lay the possibility
of a weapon.” He applied forthwith to the British Air Ministry for a ton of
uranium oxide, “ashamed of putting forward a proposal apparently so
absurd.” 1138
More ominously, two initiatives originated simultaneously in Germany as
a result of the French report.1139 A physicist at Göttingen alerted the Reich
Ministry of Education.
at led to a secret conference in Berlin on April 29,
which led in turn to a research program, a ban on uranium exports and
provision for supplies of radium from the Czechoslovakian mines at
Joachimsthal.
(Otto Hahn was invited to the conference but arranged to be
elsewhere.) e same week a young physicist working at Hamburg, Paul
Harteck, wrote a letter jointly with his assistant to the German War Office:
We take the liberty of calling to your attention the newest development in
nuclear physics, which, in our opinion, will probably make it possible to
produce an explosive many orders of magnitude more powerful than the
conventional ones....
at country which first makes use of it has an
unsurpassable advantage over the others.1140
e Harteck letter reached Kurt Diebner, a competent nuclear physicist
stuck unhappily in the Wehrmacht’s ordnance department studying high
explosives.
Diebner carried it to Hans Geiger.
Geiger recommended
pursuing the research.
e War Office agreed.
A public debate in Washington on April 29 paralleled the secret
conference in Berlin.
e New York Times account accurately summarizes
the divisions in the U.S.
physics community at the time:
Tempers and temperatures increased visibly today among members of the
American Physical Society as they closed their Spring meeting with
arguments over the probability of some scientist blowing up a sizable
portion of the earth with a tiny bit of uranium, the element which
produces radium.
1141
Dr.
Niels Bohr of Copenhagen, a colleague of Dr.
Albert Einstein at the
Institute for Advanced Study, Princeton, N.J., declared that bombardment
of a small amount of the pure Isotope U235 of uranium with slow neutron
particles of atoms would start a “chain reaction” or atomic explosion
sufficiently great to blow up a laboratory and the surrounding country for
many miles.
Many physicists declared, however, that it would be difficult, if not
impossible, to separate Isotope 235 from the more abundant Isotope 238.
e Isotope 235 is only 1 per cent of the uranium element.
Dr.
L.
Onsager of Yale University described, however, a new apparatus
in which, according to his calculations, the isotopes of elements can be
separated in gaseous form in tubes which are cooled on one side and
heated to high temperatures on the other.
Other physicists argued that such a process would be almost
prohibitively expensive and that the yield of Isotope 235 would be
infinitesimally small.
Nevertheless, they pointed out that, if Dr.
Onsager’s
process of separation should work, the creation of a nuclear explosion
which would wreck as large an area as New York City would be
comparatively easy.
A single neutron particle, striking the nucleus of a
uranium atom, they declared, would be sufficient to set off a chain
reaction of millions of other atoms.
e Times story assumes the truth of Bohr’s argument in favor of U235,
although even Bohr was apparently still emphasizing only a slowneutron
reaction.
Fermi and others were not yet convinced of U235’s role.
e two
uranium isotopes might not easily be separated in quantity, but it had
occurred to John Dunning earlier in the month that they could be separated
in microscopic amounts in Alfred Nier’s mass spectrograph.
Dunning had
immediately written Nier a long, impassioned letter asking him, in effect, to
resolve the dispute between Fermi and Bohr and push chain-reaction
research dramatically forward.
Nier, Dunning and Fermi all attended the
American Physical Society meeting.
In person Dunning urged Nier to try
for a separation much as he had urged him in the key paragraph of his letter:
ere is one line of attack that deserves strong effort, and that is where we
need your cooperation....
It is of the utmost importance to get some
uranium isotopes separated in enough quantities for a real test.
If you
could separate effectively even tiny amounts of the two main isotopes [a
third isotope, U234, is present in natural uranium to the trace extent of
one part in 17,000], there is a good chance that [Eugene T.] Booth and I
could demonstrate, by bombarding them with the cyclotron, which
isotope is responsible.
ere is no other way to settle this business.
If we
could all cooperate and you aid us by separating some samples, then we
could, by combining forces, settle the whole matter.1142
e important point for Dunning, the reason for his passion, was that if
U235 was responsible for slow-neutron fission, then its fission cross section
must be 139 times as large as the slow-neutron fission cross section of
natural uranium, since it was present in the natural substance to the extent
of only one part in 140.
“By separating the 235 isotope,” Herbert Anderson
emphasizes in a memoir, “it would be much easier to obtain the chain
reaction.
More than this, with the separated isotope the prospect for a bomb
with unprecedented explosive power would be very great.” 1143
Fermi urged Nier in similar terms; Nier recalls that he “went back and
figured out how we might soup up our apparatus some in order to increase
the output....
I did work on the problem, but at first it seemed like such a
farfetched thing that I didn’t work on it as hard as I might have.
It was just
one of a number of things I was trying to do.” 1144
Fermi in any case was more interested in pursuing a chain reaction in
natural uranium than in attempting to separate isotopes.
“He was not
discouraged by the small cross-section for fission in the natural [element],”
comments Anderson.
“ ‘Stay with me,’ he advised, ‘we’ll work with natural
uranium.
You’ll see.
We’ll be the first to make the chain reaction.’ I stuck
with Fermi.” 1145
By mid-April Szilard had managed to borrow about five hundred pounds
of black, grimy uranium oxide free of charge from the Eldorado Radium
Corporation, an organization owned by the Russian-born Pregel brothers,
Boris and Alexander.
Boris had studied at the Radium Institute in Paris;
Eldorado speculated in rare minerals and owned important uranium
deposits at Great Bear Lake in the Northwest Territories of Canada.
Like Fermi’s and Anderson’s previous experiment, the new project
involved measuring neutron production in a tank of liquid.
For a more
accurate reading the experimenters needed a longer exposure time than
their customary rhodium foils activated to 44-second half-life would allow.
ey planned instead simply to fill the tank with a 10 percent solution of
manganese, an ironlike metal that gives amethyst its purple color and that
activates upon neutron bombardment to an isotope with a nearly 3-hour
half-life.
“e [radio]activity induced in manganese,” they explained
aerward in their report, “is proportional to the number of [slow] neutrons
present.
”1146 So the hydrogen in the water would serve to slow both the
primary neutrons from the central neutron source and any secondary
neutrons from fission, and the manganese in the water would serve to
measure them—a nice economy of design.
Atoms on the surface of a mass of uranium are exposed to neutrons more
efficiently than atoms deeper inside.
Fermi and Szilard therefore decided not
to bulk their five hundred pounds of uranium oxide into one large container
but to distribute it throughout the tank by packing it into fiy-two cans as
tall and narrow as lengths of pipe—two inches in diameter and two feet
long.
Packing cans and mixing manganese solutions, which had to be changed
and the manganese concentrated aer each experimental run, was work.
So
was staying up half the night taking readings of manganese radioactivity.
Fermi accepted the challenge with gusto.
“He liked to work harder than
anyone else,” Anderson notes, “but everyone worked very hard.” Except
Szilard.
“Szilard thought he ought to spend his time thinking.” 1147 Fermi was
insulted.
“Szilard made a mortal sin,” Segrè remembers, echoing Fermi.
“He
said, ‘Oh, I don’t want to work and dirty my hands like a painter’s
assistant.’ ” 1148 When Szilard announced that he had hired a standin, a
young man whom Anderson remembers as “very competent,” Fermi
acceded to the arrangement without comment.1149 But he never again
pursued an experiment jointly with Szilard.
e arrangement as finally consummated looked like this:
Szilard’s Ra + Be source stands in the center of the tank, which holds 143
gallons of manganese solution; the fiy-two cans of UO2 gather around.
It worked.
e three physicists found neutron activity “about ten percent
higher with uranium oxide than without it.
is result shows that in our
arrangement more neutrons are emitted by uranium than are absorbed by
uranium.” 1150 But the experiment raised puzzling questions.
Resonance
absorption, for example, was clearly a problem, capturing neutrons that
might otherwise serve the chain reaction.
e report estimates “an average
emission [of secondary neutrons] of about 1.2 neutrons per thermal
neutron” but notes that “this number should be increased, to perhaps 1.5 ,”
because some of the neutrons had obviously been captured without
fissioning—demonstrating the big capture resonance around 25 eV that
Bohr had attributed on his graphs to U238.1151
Another problem was the use of water as a moderator.
As Fermi’s team
had discovered in Rome in 1934, hydrogen was more efficient than any
other element at slowing down neutrons, and slow neutrons avoided the
parasitic capture resonance of U238.
But hydrogen itself also absorbed some
slow neutrons, reducing further the number available for fission.
And it was
already clear that every possible secondary neutron would have to be
husbanded carefully if a chain reaction was to be initiated in natural
uranium.
George Placzek came down from Cornell, where he had found a
new home, for a visit, looked over the arrangement and insightfully
foreclosed its future.
As Szilard tells it:
We were inclined to conclude that...
the water-uranium system would
sustain a chain reaction....
Placzek said that our conclusion was wrong
because in order to make a chain reaction go, we would have to eliminate
the absorption of [neutrons by the] water; that is, we would have to
reduce the amount of water in the system, and if we reduced the water in
the system, we would increase the parasitic absorption of [neutrons by]
uranium [because with less water fewer neutrons would be slowed].
He
recommended that we abandon the water-uranium system and use
helium for slowing down the neutrons.
To Fermi this sounded funny, and
Fermi referred to helium thereaer invariably as Placzek’s helium.
1152
In June the Columbia team wrote up its experiment and sent the resulting
paper, “Neutron production and absorption in uranium,” to the Physical
Review, which received it on July 3.1153 Fermi le for the Summer School of
eoretical Physics at Ann Arbor, his attention diverted, says Anderson, “by
an interesting problem in cosmic rays.” 1154 Either Fermi did not share
Szilard’s sense of the urgency of chain-reaction research or he was
withdrawing for a time from the Navy’s indifference and Placzek’s persuasive
criticism of his uranium-water system; probably both.
Anderson settled
down to study resonance absorption in uranium, a project that would evolve
into his doctoral dissertation.
Szilard remained in the steamy city: “I was le alone in New York.
I still
had no position at Columbia; my three months [of laboratory privileges]
were up, but there were no experiments going on anyway and all I had to do
was to think.
”1155
* * *
Szilard thought first about an alternative to water.
e next common
material up the periodic table that might work—that had a capture cross
section considerably smaller than hydrogen’s, that was cheap, that would be
thermally and chemically stable—was carbon.
e mineral form of carbon,
chemically identical to diamond but the product of a different structure of
crystallization, is graphite, a black, greasy, opaque, lustrous material that is
the essential component of pencil lead.
Although carbon slows neutrons
much less rapidly than hydrogen, even that difference might be put to
advantage by careful design.
Lewis Strauss was leaving for Europe the week of July 2.
Hoping that the
financier might coax support for uranium research from Belgium’s Union
Miniére, Szilard sent Strauss a last-minute letter arguing that a chain
reaction in uranium “is an immediate possibility” but chose not to mention
his new uranium-graphite conception.
1156 Apparently he wanted to discuss
it first with Fermi; the same day, July 3, he wrote the Italian laureate at
length.
“It seems to me now,” he reported, “that there is a good chance that
carbon might be an excellent element to use in place of hydrogen, and there
is a strong temptation to gamble on this chance.” He wanted to try “a large-
scale experiment with a carbon-uranium-oxide mixture” as soon as they
could acquire enough material.
In the meantime he thought he would set up
a small experiment to measure more accurately carbon’s capture cross
section, only the upper limit of which was then known.
If carbon should
prove unsuitable their “next best guess might be heavy water,” rich in
deuterium, though they would need “a few tons” of that scarce and
expensive liquid.
(Deuterium, H2, has a much smaller cross section for
neutron capture than ordinary hydrogen.)
Across the one hundred sixty-third anniversary of the Declaration of
Independence Szilard’s ideas evolved rapidly.
On July 5 he visited the
National Carbon Company of New York to look into purchasing graphite
blocks of high purity (because impurities such as boron with large capture
cross sections would soak up too many neutrons).
He wrote Fermi his
finding the same day: “It seems that it will be possible to get sufficiently pure
carbon at a reasonable price.” 1157 He also mentioned arranging the uranium
and carbon in layers.
Fermi sat down in Ann Arbor at the end of the week to respond to
Szilard’s first report.
Independently he had arrived at a similar plan:
ank you for your letter.
I was also considering the possibility of using
carbon for slowing down the neutrons....
According to my estimates a
possible recipe might be about 39,000 kg of carbon mixed with 600 kg of
uranium.
If it were really so the amounts of materials would certainly not
be too large.
1158
Since however the amount of uranium that can be used, especially in a
homogeneous mixture, is exceedingly small...
perhaps the use of thick
layers of carbon separated by layers of uranium might allow use of a
somewhat larger percentage of uranium.
e idea of layering or in some other way separating the uranium from the
graphite originated in calculations Fermi made in June for the manganese
water-tank experiment.
Fermi’s calculations led both men to consider
partitioning the oxide from the graphite in the new design they were
independently evolving.
Partitioning would give the fast secondary neutrons
room to slow down, bouncing around in the moderator, before they
encountered any U238 nuclei.
Szilard’s next letter, on July 8, mentions that
“the carbon and the uranium oxide would not be mixed but built up in
layers, or in any case used in some canned form.
”1159 Both the July 5 and
July 8 letters apparently crossed with Fermi’s letter in the mail.
By the time he heard from Fermi, Szilard had seen still farther and
realized that small spheres of uranium arranged within blocks of graphite
would be “even more favorable from the point of view of a chain reaction
than the system of plane uranium layers which was initially considered.” 1160
e arrangement Szilard had in mind he called a “lattice.” (A geodesic dome
would represent such a lattice arrangement schematically if it were a
complete sphere and if all its interior volume were filled like its surface with
evenly spaced points.) His calculations indicated somewhat larger volumes
of material than had Fermi’s: “perhaps 50 tons of carbon and 5 tons of
uranium.” 1161 e entire experiment, he thought, would cost about
$35,000.1162
If a chain reaction would work in graphite and uranium, Szilard assumed,
then a bomb was probable.
And if he had managed these conclusions, he
further assumed, then so had his counterparts in Nazi Germany.
He sought
out Pegram in those early July days and tried to convince him of the urgent
need for a large-scale experiment to settle the question.
e dean resisted
the assault: “He took the position that even though the matter appeared to
be rather urgent, this being summer and Fermi being away there was really
nothing that usefully could be done until the fall.” 1163
For several weeks Szilard had been trying on his own to raise funds from
the U.S.
military.
In late May he had asked Wigner to contact the Army’s
Aberdeen Proving Ground, its weapons-development facility in Maryland.
While he was thinking through the possibilities of a uraniumgraphite system
he had talked to Ross Gunn about Navy support.
Now Fermi’s letter of July 9
and a July 10 letter from Gunn arrived to discourage him.
Fermi wrote of
layering the carbon and uranium but calculated in terms of a homogeneous
system—of graphite and uranium oxide crushed and mixed together.
Szilard
concluded he was being mocked: “I knew very well that Fermi...
computed
the homogeneous mixture only because it was the easiest to compute.
is
showed me that Fermi did not take this really seriously.
”1164 Gunn in turn
reported that “it seems almost impossible...
to carry through any sort of an
agreement [with the Navy] that would be really helpful to you.
I regret this
situation but see no escape.
”1165
Despite his Olympian ego not even Leo Szilard felt capable of saving the
world entirely alone.
He called on his Hungarian compatriots now for moral
support.
Edward Teller had moved to Manhattan for the summer to teach
physics at Columbia; Eugene Wigner came up from Princeton to conspire
with them.
In later years Szilard would recount several different versions of
how their conversation went, but a letter he wrote on August 15, 1939, offers
reliable contemporary testimony: “Dr.
Wigner is taking the stand that it is
our duty to enlist the cooperation of the [Roosevelt] Administration.
A few
weeks ago he came to New York in order to discuss this point with Dr.
Teller
and me.” 1166 Szilard had shown Wigner his uraniumgraphite calculations.
“He was impressed and he was concerned.” 1167 Both Teller and Wigner,
Szilard wrote in a background memorandum in 1941, “shared the opinion
that no time must be lost in following up this line of development and in the
discussion that followed, the opinion crystallized that an attempt ought to be
made to enlist the support of the Government rather than that of private
industry.
Dr.
Wigner, in particular, urged very strongly that the Government
of the United States be advised.” 1168
But the discussion slipped away from that project into “worry about what
would happen if the Germans got hold of large quantities of the uranium
which the Belgians were mining in the Congo.” Perhaps Szilard emphasized
the futility of the government contacts that he and Fermi had already made.
“So we began to think, through what channels could we approach the
Belgian government and warn them against selling any uranium to
Germany?” 1169
It occurred to Szilard then that his old friend Albert Einstein knew the
Queen of Belgium.
Einstein had met Queen Elizabeth in 1929 on a trip to
Antwerp to visit his uncle; thereaer the physicist and the sovereign
maintained a regular correspondence, Einstein addressing her in
plainspoken letters simply as “Queen.”
e Hungarians were aware that Einstein was summering on Long Island.
Szilard proposed visiting Einstein and asking him to alert Elizabeth of
Belgium.
Since Szilard owned no car and had never learned to drive he
enlisted Wigner to deliver him.
ey called Einstein’s office at the Institute
for Advanced Study and learned he was staying at a summer house on Old
Grove Pond on Nassau Point, the spit of land that divides Little from Great
Peconic Bay on the northeastern arm of the island.
ey called Einstein to arrange a day.
At this time Szilard also furthered
Wigner’s proposal to contact the United States government by seeking
advice from a knowledgeable emigré economist, Gustav Stolper, a Berliner
resettled in New York who had once been a member of the Reichstag.
1170
Stolper offered to try to identify an influential messenger.
Wigner picked up Szilard on the morning of Sunday, July 16, and drove
out Long Island to Peconic.1171 ey reached the area in early aernoon but
had no luck soliciting directions to the house until Szilard thought to ask for
it in Einstein’s name.
“We were on the point of giving up and going back to
New York”—two world-class Hungarians lost among country lanes in
summer heat—“when I saw a boy aged maybe seven or eight standing on
the curb.
I leaned out of the window and I said, ‘Say, do you by any chance
know where Professor Einstein lives?’ e boy knew that and he offered to
take us there.” 1172
C.
P.
Snow had visited Einstein at the same summer retreat two years
before, also losing his way, and makes the scene familiar:
He came into the sitting room a minute or two aer we arrived.
ere was
no furniture apart from some garden chairs and a small table.
e
window looked out on to the water, but the shutters were half closed to
keep out the heat.
e humidity was very high.
1173
At close quarters, Einstein’s head was as I had imagined it: magnificent,
with a humanizing touch of the comic.
Great furrowed forehead; aureole
of white hair; enormous bulging chocolate eyes.
I can’t guess what I
should have expected from such a face if I hadn’t known.
A shrewd Swiss
once said it had the brightness of a good artisan’s countenance, that he
looked like a reliable old-fashioned watchmaker in a small town who
perhaps collected butterflies on a Sunday.
What did surprise me was his physique.
He had come in from sailing
and was wearing nothing but a pair of shorts.
It was a massive body, very
heavily muscled: he was running to fat round the midriff and in the upper
arms, rather like a footballer in middle-age, but he was still an unusually
strong man.
He was cordial, simple, utterly unshy.
e large eyes looked at
me, as though he was thinking: what had I come for, what did I want to
talk about?...
e hours went on.
I have a hazy memory that several people
dried in and out of the room, but I do not remember who they were.
Stifling heat.
ere appeared to be no set time for meals.
He was already, I
think, eating very little, but he was still smoking his pipe.
Trays of open
sandwiches—various kinds of wurst, cheese, cucumber—came in every
now and then.
It was all casual and Central European.
We drank nothing
but soda water.
Similarly settled, Szilard told Einstein about the Columbia
secondaryneutron experiments and his calculations toward a chain reaction
in uranium and graphite.
Long aerward he would recall his surprise that
Einstein had not yet heard of the possibility of a chain reaction.
When he
mentioned it Einstein interjected, “Daran habe ich gar nicht gedacht!” —“I
never thought of that!” He was nevertheless, says Szilard, “very quick to see
the implications and perfectly willing to do anything that needed to be
done.1174 He was willing to assume responsibility for sounding the alarm
even though it was quite possible that the alarm might prove to be a false
alarm.
e one thing most scientists are really afraid of is to make fools of
themselves.
Einstein was free from such a fear and this above all is what
made his position unique on this occasion.” 1175
Einstein hesitated to write Queen Elizabeth but was willing to contact an
acquaintance who was a member of the Belgian cabinet.
Wigner spoke up to
insist again that the United States government should be alerted, pointing
out, Szilard goes on, “that we should not approach a foreign government
without giving the State Department an opportunity to object.” Wigner
suggested that they send the Belgian letter with a cover letter through State.
All three men thought that made sense.
Einstein dictated a letter to the Belgian ambassador, a more formal contact
appropriate to their State Department plan, and Wigner took it down in
longhand in German.
1176 At the same time Szilard draed a cover letter.
Einstein’s was the first of several such compositions—they served in
succession as dras—and the origin of most of the statements that
ultimately found their way into the letter he actually sent.
Wigner carried the first Einstein dra back to Princeton, translated it into
English and on Monday gave it to his secretary to type.
When it was ready
he mailed it to Szilard.
en he le Princeton to drive to California on
vacation.
A message from Gustav Stolper awaited Szilard at the King’s Crown.
“He
reported to me,” Szilard wrote Einstein on July 19, “that he had discussed
our problems with Dr.
Alexander Sachs, a vice-president of the Lehman
Corporation, biologist and national economist, and that Dr.
Sachs wanted to
talk to me about this matter.
”1177, 1178 Eagerly Szilard arranged an appointment.
Alexander Sachs, born in Russia, was then forty-six years old.
He had
come to the United States when he was eleven, graduated from Columbia in
biology at nineteen, worked as a clerk on Wall Street, returned to Columbia
to study philosophy and then went on to Harvard with several prestigious
fellowships to pursue philosophy, jurisprudence and sociology.
He
contributed economics text to Franklin Roosevelt’s campaign speeches in
1932; beginning in 1933 he worked for three years for the National Recovery
Administration, joining the Lehman Corporation in 1936.
He had thick
curls and a receding chin and looked and sounded like the comedian Ed
Wynn.
His associates at the NRA used to point him out to visiting firemen
under that nom de guerre as ultimate proof, if the NRA itself was not
sufficient, of Roosevelt’s gi for radical innovation.
Sachs communicated in
dense, florid prose (he had been thinking that spring of writing a book
entitled e Inter- War Retreat from Reason as Exemplified in the Mis-history
of the Recent Past and in the Contemporaneous Conduct of International
Political and Economic Affairs by the United States and Great Britain) but
could coruscate in committee.
Sachs heard Szilard out.
en, as Szilard wrote Einstein, he “took the
position, and completely convinced me, that these were matters which first
and foremost concerned the White House and that the best thing to do, also
from the practical point of view, was to inform Roosevelt.
He said that if we
gave him a statement he would make sure it reached Roosevelt in
person.
”1179 Among those who valued Sachs’ opinions and called him from
time to time for talks, it seems, was the President of the United States.
Szilard was stunned.
e very boldness of the proposal won his heart aer
all the months when he had confronted caution and skepticism: “Although I
have seen Dr.
Sachs once,” he told Einstein, “and really was not able to form
any judgment about him, I nevertheless think that it could not do any harm
to try this way and I also think that in this regard he is in a position to fulfill
his promise.” 1180
Szilard met Sachs shortly aer returning from Peconic—between Sunday
and Wednesday.
Unable at midweek to reach Wigner en route to California,
he tracked down Teller, who thought Sachs’ proposal preferable to the plan
they had previously worked out.
1181 Drawing on the first Einstein dra,
Szilard now prepared a dra letter to Roosevelt.
He wrote it in German
because Einstein’s English was insecure, added a cover letter and mailed it to
Long Island.
“Perhaps you will be able to tell me over the telephone whether
you would like to return the dra with your marginal comments by mail,” he
proposed in the cover letter, “or whether I should come out to discuss the
whole thing once more with you.” If he visited Peconic again, Szilard wrote,
he would ask Teller to drive him, “not only because I believe his advice is
valuable but also because I think you might enjoy getting to know him.
1182
He is particularly nice.”
Einstein preferred to review a letter to the President in person.
Teller
therefore delivered Szilard to Peconic, probably on Sunday, July 30, in his
sturdy 1935 Plymouth.1183 “I entered history as Szilard’s chauffeur,” Teller
aphorizes the experience.1184 ey found the Princeton laureate in old
clothes and slippers.
Elsa Einstein served tea.
Szilard and Einstein composed
a third text together, which Teller wrote down.
1185 “Yes, yes,” Teller
remembers Einstein commenting, “this would be the first time that man
releases nuclear energy in a direct form rather than indirectly.” 1186 Directly
from fission, he meant, rather than indirectly from the sun, where a different
nuclear reaction produces the copious radiation that reaches the earth as
sunlight.
Einstein apparently questioned if Sachs was the best man to carry the
news to Roosevelt.
On August 2 Szilard wrote Einstein hoping “at long last”
for a decision “upon whom we should try to get as middle man.” 1187 He had
seen Sachs in the interim; the economist, who certainly coveted the
assignment of representing Albert Einstein to the President, had generously
listed the financier Bernard Baruch or Karl T.
Compton, the president of
MIT, as possible alternates.
On the other hand, he had strongly endorsed
Charles Lindbergh, though he must have known that Roosevelt despised the
famous aviator for his outspoken pro-German isolationism.
Szilard wrote
that he and Sachs had discussed “a somewhat longer and more extensive
version” of the letter Einstein had written with Szilard at their second
Peconic meeting; he now enclosed both the longer and shorter versions and
asked Einstein to return his favorite along with a letter of introduction to
Lindbergh.
Einstein opted for the longer version, which incorporated the shorter
statement that had originated with him but carried additional paragraphs
contributed by Szilard in consultation with Sachs.
He signed both letters and
returned them to Szilard in less than a week with a note hoping “that you
will finally overcome your inner resistance; it’s always questionable to try to
do something too cleverly.” 1188 at is, be bold and get moving.
“We will try
to follow your advice,” Szilard rejoined on August 9, “and as far as possible
overcome our inner resistances which, admittedly, exist.
Incidentally, we are
surely not trying to be too clever and will be quite satisfied if only we don’t
look too stupid.
”1189
Szilard transmitted the letter in its final form to Sachs on August 15 along
with a memorandum of his own that elaborated on the letter’s discussion of
the possibilities and dangers of fission.
He had not given up contacting
Lindbergh—he draed a letter to the aviator the following day—but he
seems to have decided to try Sachs in the meantime, probably in the interest
of moving the project on; he pointedly asked Sachs either to deliver the letter
to Roosevelt or to return it.1190
One of the discussions Szilard had added to the longer dra that Einstein
chose concerned who should serve as liaison between “the Administration
and the group of physicists working on chain reactions in America.” 1191 In
his letter of transmittal to Sachs, Szilard now tacitly offered himself for that
service.
“If a man, having courage and imagination, could be found,” he
wrote, “and if such a man were put—in accordance with Dr.
Einstein’s
suggestion—in the position to act with some measure of authority in this
matter, this would certainly be an important step forward.
In order that you
may be able to see of what assistance such a man could be in our work, allow
me please to give you a short account of the past history of the case.
”1192 e
short account that followed, an abbreviated and implicit curriculum vitae,
essentially outlined Szilard’s own role since Bohr’s announcement of the
discovery of fission seven crowded months earlier.
Szilard’s offer was as innocent of American bureaucratic politics as it was
bold.
It was surely also the apotheosis of his drive to save the world.
By this
time the Hungarians at least believed they saw major humanitarian benefit
inherent in what Eugene Wigner would describe in retrospect as “a horrible
military weapon,” explaining:1193
Although none of us spoke much about it to the authorities [during this
early period]—they considered us dreamers enough as it was—we did
hope for another effect of the development of atomic weapons in addition
to the warding off of imminent disaster.
We realized that, should atomic
weapons be developed, no two nations would be able to live in peace with
each other unless their military forces were controlled by a common
higher authority.
We expected that these controls, if they were effective
enough to abolish atomic warfare, would be effective enough to abolish
also all other forms of war.
is hope was almost as strong a spur to our
endeavors as was our fear of becoming the victims of the enemy’s atomic
bombings.
From the horrible weapon which they were about to urge the United
States to develop, Szilard, Teller and Wigner—“the Hungarian conspiracy,”
Merle Tuve was amused to call them—hoped for more than deterrence
against German aggression.
1194 ey also hoped for world government and
world peace, conditions they imagined bombs made of uranium might
enforce.
* * *
Alexander Sachs intended to read aloud to the President when he met with
him.
He believed busy people saw so much paper they tended to dismiss the
printed word.
“Our social system is such,” he told a Senate committee in
1945, “that any public figure [is] punch-drunk with printer’s ink....
1195 is
was a matter that the Commander in Chief and the head of the Nation must
know.
I could only do it if I could see him for a long stretch and read the
material so it came in by way of the ear and not as a so mascara on the eye.”
He needed a full hour of Franklin Delano Roosevelt’s time.
History intervened to crowd the President’s calendar.
Having won the
Rhineland, Austria and Czechoslovakia simply by taking them, having
signed the Pact of Steel with Italy on May 22 and a ten-year treaty of
nonaggression and neutrality with the USSR on August 23, Adolf Hitler
ordered the invasion of Poland beginning at 4:45 A.M.
on September 1, 1939,
and precipitated the Second World War.
e German invasion fielded fiy-
six divisions against thirty Polish divisions strung thinly across the long
Polish frontier; Hitler had ten times the aircra, including plentiful
squadrons of Stuka dive-bombers, and nine divisions of Panzer tanks against
Polish horse cavalry armed with swords and spears.
e assault was “a
perfect specimen of the modern Blitzkrieg,” writes Winston Churchill: “the
close interaction on the battlefield of army and air force; the violent
bombardment of all communications and of any town that seems an
attractive target; the arming of an active Fih Column; the free use of spies
and parachutists; and above all, the irresistible forward thrusts of great
masses of armour.” 1196
e mathematician Stanislaw Ulam had just returned from visiting
Poland, bringing with him on a student visa his sixteen-year-old brother,
Adam:
Adam and I were staying in a hotel on Columbus Circle.
It was a very hot,
humid, New York night.
I could not sleep very well.
It must have been
around one or two in the morning when the telephone rang.
Dazed and
perspiring, very uncomfortable, I picked up the receiver and the somber,
throaty voice of my friend the topologist Witold Hurewicz began to recite
the horrible tale of the start of war: “Warsaw has been bombed, the war
has begun,” he said.
is is how I learned about the beginning of World
War II.
He kept describing what he had heard on the radio.
I turned on
my own.
Adam was asleep; I did not wake him.
ere would be time to
tell him the news in the morning.
Our father and sister were in Poland, so
were many other relatives.
At that moment, I suddenly felt as if a curtain
had fallen on my past life, cutting it off from my future.
ere has been a
different color and meaning to everything ever since.1197
One of Roosevelt’s first acts was to appeal to the belligerents to refrain
from bombing civilian populations.
Revulsion against the bombing of cities
had grown in the United States since at least the Japanese bombing of
Shanghai in 1937.1198 When Spanish Fascists bombed Barcelona in March
1938, Secretary of State Cordell Hull had condemned the atrocity publicly:
“No theory of war can justify such conduct,” he told reporters.
“...
I feel
that I am speaking for the whole American people.” 1199 In June the Senate
passed a resolution condemning the “inhuman bombing of civilian
populations.
”1200 As war approached, revulsion began to give way to
impulses of revenge; in the summer of 1939 Herbert Hoover could urge an
international ban on the bombing of cities and still argue that “one of the
impelling reasons for the unceasing building of bombing planes is to prepare
reprisals.” 1201 Bombing was bad because it was enemy bombing.
Scientific
American saw through to a darker truth: “Although...
aerial bombing
remains an unknown, indeterminate quantity, the world may be sure that
the unwholesome atrocities which are happening today are but curtain
raisers on insane dramas to come.
”1202
So although Roosevelt had asked Congress for increased funds for long-
range bombers nine months before, in appealing to the belligerents on
September 1, 1939, he could still articulate the moral indignation of millions
of Americans:
e ruthless bombing from the air of civilians in unfortified centers of
population during the course of the hostilities which have raged in
various quarters of the earth during the past few years, which has resulted
in the maiming and in the death of thousands of defenseless men, women
and children, has sickened the hearts of every civilized man and woman,
and has profoundly shocked the conscience of humanity.
1203
If resort is had to this form of inhuman barbarism during the period of
the tragic conflagration with which the world is now confronted,
hundreds of thousands of innocent human beings who have no
responsibility for, and who are not even remotely participating in, the
hostilities which have now broken out, will lose their lives.
I am therefore
addressing this urgent appeal to every Government which may be
engaged in hostilities publicly to affirm its determination that its armed
forces shall in no event, and under no circumstances, undertake the
bombardment from the air of civilian populations or of unfortified cities,
upon the understanding that these same rules of warfare will be
scrupulously observed by all of their opponents.
I request an immediate
reply.
Great Britain agreed to the President’s terms the same day.
Germany, busy
bombing Warsaw, concurred on September 18.
e invasion of Poland brought Britain and France into the war on
September 3.
Abruptly Roosevelt’s schedule filled to overflowing.
In early
September in particular he was working overtime with a reluctant Congress
to revise the Neutrality Act to terms more favorable to Britain; Sachs was
unable even to discuss arranging an interview until aer the first week in
September.
* * *
By September Kurt Diebner’s new War Office department had consolidated
German fission research under its authority.
Diebner enlisted a young
Leipzig theoretician named Erich Bagge and together the two physicists
planned a secret conference to consider the feasibility of a weapons
project.1204 ey had the authority to enlist the services of any German
citizen they wished and they used it, sending out papers that le Hans
Geiger, Walther Bothe, Otto Hahn and a number of other exceptional older
men nervously uncertain if they were being invited to Berlin for
consultation or ordered to active military service.
At the conference in Berlin on September 16 the physicists learned that
German intelligence had discovered the beginnings of uranium research
abroad—meaning, presumably, in the United States and Britain.
ey
discussed the long, thorough theoretical paper by Niels Bohr and John
Wheeler, “e mechanism of nuclear fission,” that had been published in the
September Physical Review and especially its conclusion, which Bohr and
Wheeler had elaborated from Bohr’s Sunday-morning graph work, that
U235 was probably the isotope of uranium responsible for slow-neutron
fission.
1205 Hahn like Bohr argued that isotope separation was difficult to the
point of impossibility.
Bagge proposed calling in Werner Heisenberg, his
superior at Leipzig, to adjudicate.
Heisenberg therefore attended a second Berlin conference on September
26 and discussed two possible ways to harness the energy from fission: by
slowing secondary neutrons with a moderator to make a “uranium burner”
and by separating U235 to make an explosive.
Paul Harteck, the Hamburg
physicist who had written the War Office the previous April, traveled to the
second conference armed with a paper he had just finished on the
importance of layering uranium and moderator to avoid the U238 capture
resonance—the same insight that had come independently to Fermi and
Szilard in early July.
Harteck’s study, however, considered using heavy water
as moderator, even though Harteck had worked with Rutherford at the
Cavendish and knew from personal experience how expensive heavy-water
production could be—water in which deuterium replaced hydrogen had to
be tediously distilled from tons of ordinary H20.
Diebner and Bagge had outlined for the second conference a “Preparatory
Working Plan for Initiating Experiments on the Exploitation of Nuclear
Fission.
”1206 Heisenberg would head up theoretical investigation.
Bagge
would measure deuterium’s cross section for collision to establish how
effectively heavy water might slow secondary neutrons.
Harteck would look
into isotope separation.
Others would experiment to determine other
significant nuclear constants.
e War Office would take over the Kaiser
Wilhelm Institute of Physics, finished in 1937 and beautifully equipped.
Adequate funds would be forthcoming.
e German atomic bomb project was well begun.
It may have been no less complicated by humanitarian ambiguities than
the project the Hungarians in the United States proposed.
One young but
highly respected German physicist involved in the work from near the
beginning was Carl Friedrich von Weizsäcker, the son of the German
Undersecretary of State.
In a 1978 memoir von Weizsäcker remembers
discussing the possibility of a bomb with Otto Hahn in the spring of 1939.
Hahn opposed secrecy then partly on the grounds of scientific ethics but
also partly because he “felt that if it were to be made, it would be worst for
the entire world, even for Germany, if Hitler were to be the only one to have
it.” Like Szilard, Teller and Wigner, von Weizsäcker remembers realizing in
discussions with a friend “that this discovery could not fail to radically
change the political structure of the world” :1207
To a person finding himself at the beginning of an era, its simple
fundamental structures may become visible like a distant landscape in the
flash of a single stroke of lightning.
But the path toward them in the dark
is long and confusing.
At that time [i.e., 1939] we were faced with a very
simple logic.
Wars waged with atom bombs as regularly recurring events,
that is to say, nuclear wars as institutions, do not seem reconcilable with
the survival of the participating nations.
But the atom bomb exists.
It
exists in the minds of some men.
According to the historically known
logic of armaments and power systems, it will soon make its physical
appearance.
If that is so, then the participating nations and ultimately
mankind itself can only survive if war as an institution is abolished.
Both sides might work from fear of the other.
But some on both sides would
be working also paradoxically believing they were preparing a new force that
would ultimately bring peace to the world.
* * *
As September extended its violence Szilard grew impatient.
He had heard
nothing from Alexander Sachs.
Pursuing Sachs’ previous suggestions and his
own leads, he arranged for Eugene Wigner to give him a letter of
introduction to MIT president Karl T.
Compton; recontacted a businessman
of possible influence whom he had once interested in the Einstein-Szilard
refrigerator pump; read a newspaper account of a Lindbergh speech and
reported to Einstein that the aviator “is in fact not our man.” 1208 Finally, the
last week in September, he and Wigner visited Sachs and found to their
dismay that the economist still held Einstein’s letter.
“He says he has spoken
repeatedly with Roosevelt’s secretary,” Szilard reported to Einstein on
October 3, “and has the impression that Roosevelt is so overburdened that it
would be wiser to see him at a later date.
He intends to go to Washington
this week.” e two Hungarians were ready to start over: “ere is a distinct
possibility that Sachs will be of no use to us.
If this is the case, we must put
the matter in someone else’s hands.
Wigner and I have decided to accord
Sachs ten days’ grace.
en I will write you again to let you know how
matters stand.” 1209
But Alexander Sachs did indeed travel to Washington, not that week but
the next, and on Wednesday, October 11, presented himself, probably in the
late aernoon, at the White House.1210 Roosevelt’s aide, General Edwin M.
Watson, “Pa” to Roosevelt and his intimates, sitting with his own executive
secretary and military aide, reviewed Sachs’ agenda.
1211 When he was
convinced that the information was worth the President’s time, Watson let
Sachs into the Oval Office.
“Alex,” Roosevelt hailed him, “what are you up to?” 1212
Sachs liked to warm up the President with jokes.
His sense of humor
tended to learned parables.
Now he told Roosevelt the story of the young
American inventor who wrote a letter to Napoleon.1213 e inventor
proposed to build the emperor a fleet of ships that carried no sail but could
attack England in any weather.
He had it in his power to deliver Napoleon’s
armies to England in a few hours without fear of wind or storm, he wrote,
and he was prepared to submit his plans.
Napoleon scoffed: ships without
sails?
“Bah!
Away with your visionists!” 1214
e young inventor, Sachs concluded, was Robert Fulton.
Roosevelt
laughed easily; probably he laughed at that.
Sachs cautioned the President to listen carefully: what he had now to
impart was at least the equivalent of the steamboat inventor’s proposal to
Napoleon.
Not yet ready to listen, Roosevelt scribbled a message and
summoned an aide.
Shortly the aide returned with a treasure, a carefully
wrapped bottle of Napoleon brandy that the Roosevelts had preserved in the
family for years.
e President poured two glasses, passed one to his visitor,
toasted him and settled back.
Sachs had made a file for Roosevelt’s reading of Einstein’s letter and
Szilard’s memorandum.
But neither document had suited his sense of how
to present the information to a busy President.
“I am an economist, not a
scientist,” he would tell friends, “but I had a prior relationship with the
President, and Szilard and Einstein agreed I was the right person to make
the relevant elaborate scientific material intelligible to Mr.
Roosevelt.
No
scientist could sell it to him.
”1215, 1216 Sachs had therefore prepared his own version of the fission story, a composite and paraphrase of the contents of
the Einstein and Szilard presentations.
ough he le those statements with
Roosevelt, he read neither one of them aloud.
He read not Einstein’s
subsequently famous letter but his own eight-hundred-word summation, the
first authoritative report to a head of state of the possibility of using nuclear
energy to make a weapon of war.1217 It emphasized power production first,
radioactive materials for medical use second and “bombs of hitherto
unenvisaged potency and scope” third.
It recommended making
arrangements with Belgium for uranium supplies and expanding and
accelerating experiment but imagined that American industry or private
foundations would be willing to foot the bill.
To that end it proposed that
Roosevelt “designate an individual and a committee to serve as a liaison”
between the scientists and the Administration.
Sachs had intentionally listed the peaceful potentials of fission first and
second among its prospects.1218 To emphasize the “ambivalence” of the
discovery, he said later, the “two poles of good and evil” it embodied, he
turned near the end of the discussion to Francis Aston’s 1936 lecture, “Forty
Years of Atomic eory”—it had been published in 1938 as part of a
collection, Background to Modern Science, which Sachs had brought along to
the White House—where the English spectroscopist had ridiculed “the more
elderly and apelike of our prehistoric ancestors” who “objected to the
innovation of cooked food and pointed out the grave dangers attending the
use of the newly discovered agency, fire.
”1219 Sachs read the entire last
paragraph of the lecture to Roosevelt, emphasizing the final sentences:1220
Personally I think there is no doubt that sub-atomic energy is available all
around us, and that one day man will release and control its almost
infinite power.
We cannot prevent him from doing so and can only hope
that he will not use it exclusively in blowing up his next door neighbor.
“Alex,” said Roosevelt, quickly understanding, “what you are aer is to see
that the Nazis don’t blow us up.” 1221
“Precisely,” Sachs said.
Roosevelt called in Watson.
“is requires action,” he told his aide.
Meeting aerward with Sachs, Watson went by the book.
He proposed a
committee consisting initially of the director of the Bureau of Standards, an
Army representative and a Navy representative.
e Bureau of Standards,
established by Act of Congress in 1901, is the nation’s physics laboratory,
charged with applying science and technology in the national interest and
for public benefit.
Its director in 1939 was Dr.
Lyman J.
Briggs, a Johns
Hopkins Ph.D.
and a government scientist for forty-three years who had
been nominated by Herbert Hoover and appointed by FDR.
e military
representatives were Lieutenant Colonel Keith F.
Adamson and Commander
Gilbert C.
Hoover, both ordnance experts.
“Don’t let Alex go without seeing me again,” Roosevelt had directed
Watson.
1222 Sachs met the same evening with Briggs, briefed him and
proposed he and his committee of two get together with the physicists
working on fission.
Briggs agreed.
Sachs saw the President again and
declared himself satisfied.
at was good enough for Roosevelt.
Briggs set a first meeting of the Advisory Committee on Uranium for
October 21 in Washington, a Saturday.
Sachs proposed to invite the emigrés;
to counterbalance them Briggs invited Tuve, who found a schedule conflict
and deputized Richard Roberts as his stand-in.1223 Fermi, still nursing his
Navy grievance, refused to attend but was willing to allow Teller to speak in
his behalf.
On the appointed day the Hungarian conspiracy breakfasted with
Sachs at the Carleton Hotel, the out-of-towners having arrived the night
before.
1224 From the hotel they proceeded to the Department of Commerce.
e meeting then counted nine participants: Briggs, a Briggs assistant,
Sachs, Szilard, Wigner, Teller, Roberts, Adamson for the Army and Hoover
for the Navy.
Szilard began by emphasizing the possibility of a chain reaction in a
uranium-graphite system.
1225 Whether such a system would work, he said,
depended on the capture cross section of carbon and that was not yet
sufficiently known.
If the value was large, they would know that a large-scale
experiment would fail.
If the value was extremely small, a large-scale
experiment would look highly promising.
An intermediate value would
necessitate a large-scale experiment to decide.
He estimated the destructive
potential of a uranium bomb to be as much as twenty thousand tons of high-
explosive equivalent.
Such a bomb, he had written in the memorandum
Sachs carried to Roosevelt, would depend on fast neutrons and might be
“too heavy to be transported by airplane,” which meant he was still thinking
of exploding natural uranium, not of separating U235.
1226
Adamson, openly contemptuous, butted in.
“In Aberdeen,” Teller
remembers him sneering, “we have a goat tethered to a stick with a ten-foot
rope, and we have promised a big prize to anyone who can kill the goat with
a death ray.
Nobody has claimed the prize yet.” 1227 As for twenty thousand
tons of high explosive, the Army officer said, he’d been standing outside an
ordance depot once when it blew up and it hadn’t even knocked him
down.1228
Restraining himself, Wigner spoke aer Szilard, supporting his
compatriot’s argument.
Roberts raised serious objection.
1229 He was convinced that Szilard’s
optimism for a chain reaction was premature and his notion of a fast-
neutron weapon made of natural uranium misguided.
Roberts had co-
authored a review of the subject just one month before.
It agreed with
Szilard that “there are not yet sufficient data to say definitely whether or not
a uranium powerhouse is a possibility.
”1230 But it also assessed—because the
DTM had begun assessing—the question of the fast-neutron fission of
natural uranium and found, because of resonance capture and extensive
scattering of fast neutrons, that it was “very unlikely that the fast neutrons
can produce a sufficient number of fissions to maintain a [chain]
reaction.
”1231, 1232
e DTM physicist also pointed out that other lines of research might be
more promising than a slow-neutron chain reaction in natural uranium.
He
meant isotope separation.
At the University of Virginia Jesse Beams,
formerly Ernest Lawrence’s colleague at Yale, was applying to the task the
high-speed centrifuges he was developing there.
Roberts thought answers to
these questions might require several years of work and that research should
be le in the meantime to the universities.
Briggs spoke up to defend his committee.1233 He argued vigorously that
any assessment of the possibilities of fission at a time when Europe was at
war had to include more than physics; it had to include the potential impact
of the development on national defense.
Szilard was “astonished,” as he told Pegram the next day, at Sachs’ “active
and enthusiastic” participation in the meeting.1234 Sachs seconded Briggs
and the Hungarians.
“e issue was too important to wait,” he recalled his
argument, “and the important thing was to be helpful because if there was
something to it there was danger of our being blown up.
We had to take time
by the forelock, and we had to be ahead.
”1235
en it was Teller’s turn.
For himself, he announced in his deep, heavily
accented voice, he strongly supported Szilard.
But he had also been given the
task of serving as messenger for Fermi and Tuve, who had discussed these
issues in New York and had come to some agreement about them.
“I said
that this needed a little support.
In particular we needed to acquire a good
substance to slow down the neutrons, therefore we needed pure graphite,
and this is expensive.
”1236 Jesse Beams’ centrifuge work also required
support, Teller added.
“How much money do you need?” Commander Hoover wanted to
know.
1237
Szilard had not planned to ask for money.
“e diversion of Government
funds for such purposes as ours appears to be hardly possible,” he explained
to Pegram the next day, “and I have therefore myself avoided to make any
such recommendation.” 1238 But Teller answered Hoover promptly, probably
speaking for Fermi: “For the first year of this research we need six thousand
dollars, mostly in order to buy the graphite.” (“My friends blamed me
because the great enterprise of nuclear energy was to start with such a
pittance,” Teller reminisces; “they haven’t forgiven me yet.
”1239 Szilard, who
would write Briggs on October 26 that the graphite alone for a largescale
experiment would cost at least $33,000, must have been appalled.
1240)
Adamson had anticipated just such a raid on the public treasury.
“At this
point,” says Szilard, “the representative of the Army started a rather longish
tirade”:
He told us that it was naive to believe that we could make a significant
contribution to defense by creating a new weapon.
He said that if a new
weapon is created, it usually takes two wars before one can know whether
the weapon is any good or not.
en he explained rather laboriously that
it is in the end not weapons which win the wars, but the morale of the
troops.
He went on in this vein for a long time until suddenly Wigner, the
most polite of us, interrupted him.
[Wigner] said in his high-pitched
voice that it was very interesting for him to hear this.
He always thought
that weapons were very important and that this is what costs money, and
this is why the Army needs such a large appropriation.
But he was very
interested to hear that he was wrong: it’s not weapons but the morale
which wins the wars.
And if this is correct, perhaps one should take a
second look at the budget of the Army, and maybe the budget could be
cut.
1241
“All right, all right,” Adamson snapped, “you’ll get your money.
”1242
e Uranium Committee produced a report for the President on
November 1.
1243 It narrowly emphasized exploring a controlled chain
reaction “as a continuous source of power in submarines.” In addition, it
noted, “If the reaction turns out to be explosive in character, it would
provide a possible source of bombs with a destructiveness vastly greater than
anything now known.” e committee recommended “adequate support for
a thorough investigation.” Initially the government might undertake to
supply four tons of pure graphite (this would allow Fermi and Szilard to
measure the capture cross section of carbon) and, if justified later, fiy tons
of uranium oxide.
Briggs heard from Pa Watson on November 17.
e President had read
the report, Watson wrote, and wanted to keep it on file.
On file is where it
remained, mute and inactive, well into 1940.
Even with Szilard and Fermi stalled, fission studies continued at many
other American laboratories.
Prodded by a late-October letter from Fermi,
for example, Alfred Nier at the University of Minnesota finally began
preparing to separate enough U235 from U238, using his mass
spectroscope, to determine experimentally which isotope is responsible for
slow-neutron fission.
1244, 1245 But to American physicists and administrators in and out of government a bomb of uranium seemed a remote possibility at
best.
However intense their sympathies, the war was still a European war.
11
Cross Sections
In the days before the war, Otto Frisch remembers, in Hamburg with Otto
Stern, he used to run experiments by day and think intensely about physics
well into the night.
“I regularly came home,” Frisch told an interviewer once,
“had dinner at seven, had a quarter of an hour’s nap aer dinner, and then I
sat down happily with a sheet of paper and a reading lamp and worked until
about one o’clock at night—until I began to have hallucinations....
I began
to see queer animals against the background of my room, and then I
thought, Oh, well, better go to bed.’ ” e young Austrian’s hypnagogic
visions were “unpleasant feelings” but otherwise “it was an ideal life.
I’d
never had such a pleasant life, ever—this concentrated five hours work every
night.” 1246
rough the spring of 1939, in contrast, aer his early experiments with
fission, Frisch found himself “in a state of complete doldrums.
I had a
feeling war was coming.
What was the use of doing any research?
I simply
couldn’t brace myself.
I was in a pretty bad state, feeling, ‘Nothing I start
now is going to be any good.’ ”1247 As his aunt, Lise Meitner, worried about
her isolation in Stockholm, Frisch worried about his vulnerability in
Copenhagen; when British colleagues visited he uncharacteristically
campaigned among them:
I first spoke to Blackett and then Oliphant when they passed through
Copenhagen and said that I had a fear that Denmark would soon be
overrun by Hitler, and if so, would there be a chance for me to go to
England in time, because I’d rather work for England than do nothing or
be compelled in some way or other to work for Hitler or be sent to a
concentration camp.
1248
Mark Oliphant directed the physics department at the University of
Birmingham.
Rather than initiate some complicated sponsorship he simply
invited Frisch to visit him that summer to talk over the problem.
“So I
packed two small suitcases and traveled by ship and train, just like any
tourist.” 1249 e war overtook him safe in the English Midlands but with
nothing more of his possessions on hand than the contents of his two small
suitcases.
His friends in Copenhagen had to store his belongings and
arrange the repossession of the piano he was buying.
Oliphant found him work as an auxiliary lecturer.
In that relative security
he began to think about physics again.
Fission still intrigued him.
He lacked
the neutron source he would need for direct attack.
But he had followed
Bohr’s theoretical work: the distinction between the fissile characteristics of
U235 and U238 in February; the major Bohr-Wheeler paper in September
just as the German invasion of Poland brought war, “a great feeling of tense
sobriety.
”1250 He wondered if Bohr was right that U235 was the isotope
responsible for slow-neutron fission.
He conceived a way to find out: by
preparing “a sample of uranium in which the proportions of the two
isotopes were changed.
”1251 at meant at least partly separating the
isotopes, as Fermi and Dunning had encouraged Nier to do for the same
reason.
Frisch read up on methods.
e simplest, he decided, was gaseous
thermal diffusion, a technique developed by the German physical chemist
Klaus Clusius.
For equipment it required little more than a long tube
standing on end with a heated rod inside running down its center.
Fill the
tube with some gaseous form of the material to be separated, cool the tube
wall by flushing it with water, and “material enriched in the lighter isotope
would accumulate near the top...
while the heavier isotope would tend to
go to the bottom.” 1252
Frisch set out to assemble his Clusius tube.
Progress was slow.
He planned
to make the tube of glass, but the laboratory glassblower’s first priority was
Oliphant’s secret war work, work about which Frisch, technically an enemy
alien, was not supposed to know.
Two physicists on Oliphant’s staff, James
Randall and H.
A.
H.
Boot, were in fact developing the cavity magnetron, an
electron tube capable of generating intense microwave radiation for ground
and airborne radar—in C.
P.
Snow’s assessment “the most valuable English
scientific innovation in the Hitler war.
”1253
Meanwhile the British Chemical Society asked Frisch to write a review of
advances in experimental nuclear physics for its annual report.
“I managed
to write that article in my bed-sitter where in daytime, with the gas fire
going all day, the temperature rose to 42° Fahrenheit...
while at night the
water froze in the tumbler at my bedside.” He wore his winter coat, set his
typewriter on his lap and pulled his chair close to the fire.
“e radiation
from the gas fire stimulated the blood supply to my brain, and the article
was completed on time.
”1254
Frisch’s review article mentioned the possibility of a chain reaction only to
discount it.
He based that conclusion on Bohr’s argument that the U238 in
natural uranium would scatter fast neutrons, slowing them to capture-
resonance energies; the few that escaped capture would not suffice, he
thought, to initiate a slow-neutron chain reaction in the scarce U235.
Slow
neutrons in any case could never produce more than a modest explosion,
Frisch pointed out; they took too long slowing down and finding a nucleus.
As he explained later:
at process would take times of the order of a sizeable part of a
millisecond [i.e., a thousandth of a second], and for the whole chain
reaction to develop would take several milliseconds; once the material got
hot enough to vaporize, it would begin to expand and the reaction would
be stopped before it got much further.
So the thing might blow up like a
pile of gunpowder, but no worse, and that wasn’t worth the trouble.
1255
Not long from Nazi Germany, Frisch found his argument against a violently
explosive chain reaction reassuring.
It was backed by the work of no less a
theoretician than Niels Bohr.
With satisfaction he published it.
It had seen the light of day before, most notably in an August 5, 1939,
letter from Member of Parliament Winston Churchill to the British
Secretary of State for Air.
Concerned that Hitler might bluff Neville
Chamberlain with threats of a new secret weapon, Churchill had collected a
briefing from Frederick Lindemann and written to caution the cabinet not
to fear “new explosives of devastating power” for at least “several years.” e
best authorities, the distinguished M.P.
emphasized with a nod to Niels
Bohr, held that “only a minor constituent of uranium is effective in these
processes.” at constituent would need to be laboriously extracted for any
large-scale effects.
“e chain process can take place only if the uranium is
concentrated in a large mass,” Churchill continued, slightly muddling the
point.
“As soon as the energy develops, it will explode with a mild
detonation before any really violent effects can be produced.
It might be as
good as our present-day explosives, but it is unlikely to produce anything
very much more dangerous.” He concluded optimistically: “Dark hints will
be dropped and terrifying whispers will be assiduously circulated, but it is to
be hoped that nobody will be taken in by them.” 1256
Frisch found a friend that year in a fellow emigré at Birmingham, the
theoretician Rudolf Peierls.
A well-off Berliner, a slender man with a boyish
face, a notable overbite and a mind of mathematical austerity, Peierls was
born in 1907 and had arrived in England in 1933 on a Rockefeller
Fellowship to Cambridge.
With the Nazi purge of the German universities
he chose to remain in England.
He would be naturalized as a British citizen
in February 1940, but until then he was technically an enemy alien.
When
Oliphant consulted with him from time to time on the mathematics of
resonant cavities—important for microwave radar—both men were careful
to pretend that the question was purely academic.1257
Peierls had already contributed significantly to the debate on the possible
explosive effects of fission.
e previous May one of Frederic Joliot’s
associates in Paris, Francis Perrin, had published a first approximate formula
for calculating the critical mass of uranium—the amount of uranium
necessary to sustain a chain reaction.
A lump smaller than a critical mass
would be inert; a lump of critical size would explode spontaneously upon
assembly.
e possibility of a critical mass is anchored in the fact that the surface
area of a sphere increases more slowly with increasing radius than does the
volume (as nearly r 2 to r 3).
At some particular volume, depending on the
density of the material and on its cross sections for scattering, capture and
fission, more neutrons should find nuclei to fission than find surface to
escape from; that volume is then the critical mass.
Estimating the several
cross sections of natural uranium, Francis Perrin put its critical mass at
forty-four tons.
A tamper around the uranium of iron or lead to bounce
back neutrons might reduce the requirement, Perrin calculated, to only
thirteen tons.
Peierls saw immediately that he could sharpen Perrin’s formula.
1258, 1259
He did so in a theoretical paper he worked out in May and early June 1939
that the Cambridge Philosophical Society published in its Proceedings in
October.
Because a critical-mass formula based on slow-neutron fission
would be mathematically complicated, requiring that the characteristics of
the moderator be taken into account, Peierls proposed to consider “a
simplified case”: fission by unmoderated fast neutrons.
Plugging in the
fission cross section of natural uranium, which was essentially the fission
cross section of U238, gave a critical mass, notes Peierls, “of the order of
tons.” As a weapon, an object of that size was too unwieldy to take seriously.
“ere was of course no chance of getting such a thing into any aeroplane,
and the paper appeared to have no practical significance.
”1260 Peierls was
aware of the British and American concern for secrecy, but in this case he
saw no reason not to publish.
e USSR opportunistically invaded Finland at the end of November.
In
the rest of Europe the strange standoff prevailed that isolationist Idaho
senator William Borah would label the “phony war.” e Peierlses moved to
a larger house; early in the new year they generously invited Frisch to live
with them.
Genia Peierls, who was Russian, took the bachelor Austrian in
hand.
She “ran her house,” writes Frisch, “with cheerful intelligence, a
ringing Manchester voice and a Russian’s sovereign disregard of the definite
article.
She taught me to shave every day and to dry dishes as fast as she
washed them, a skill that has come in useful many times since.
”1261 Life at
the Peierlses was entertaining, but Frisch walked home through ominous
blackouts so dark that he sometimes stumbled over roadside benches and
could distinguish fellow pedestrians only by the glow of the luminous cards
they had taken to wearing in their hatbands.
us reminded of the
continuing threat of German bombing, he found himself questioning his
confident Chemical Society review: “Is that really true what I have
written?
”1262
Sometime in February 1940 he looked again.
ere had always been four
possible mechanisms for an explosive chain reaction in uranium:
(1) slow-neutron fission of U238;
(2) fast-neutron fission of U238;
(3) slow-neutron fission of U235; and
(4) fast-neutron fission of U235.
Bohr’s logical distinction between U238 and thorium on the one hand and
U235 on the other ruled out (1): U238 was not fissioned by slow neutrons.
(2) was inefficient because of scattering and the parasitic effects of the
capture resonance of U238.
(3) was possibly applicable to power production
but too slow for a practical weapon.
But what about (4)?
Apparently no one
in Britain, France or the United States had asked the question quite that way
before.
If Frisch now glimpsed an opening into those depths he did so because he
had looked carefully at isotope separation and had decided it could be
accomplished even with so fugitive an isotope as U235.
He was therefore
prepared to consider the behavior of the pure substance unalloyed with
U238, as Bohr, Fermi and even Szilard had not yet been.
“I wondered—
assuming that my Clusius separation tube worked well—if one could use a
number of such tubes to produce enough uranium-235 to make a truly
explosive chain reaction possible, not dependent on slow neutrons.
How
much of the isotope would be needed?
”1263
He shared the problem with Peierls.
Peierls had his critical-mass formula.
In this case it required the cross section for fast-neutron fission of U235, a
number no one knew because no one had yet separated a sufficient amount
of the rare isotope to determine its cross section by experiment, the only
way the number could be reliably known.
Nevertheless, says Peierls, “we had
read the paper of Bohr and Wheeler and had understood it, and it seemed to
convince us that in those circumstances for neutrons in U235 the cross-
section would be dominated by fission.” Peierls could state simply what
followed: “If a neutron hit the [U235] nucleus something was bound to
happen.” 1264
What followed thus made the cross section intuitively obvious: it would be
more or less the same as the familiar cross section that expressed the odds of
hitting the uranium nucleus with a neutron at all—the geometric cross
section, 10-23 square centimeters, an entire order of magnitude larger than
the fission cross sections previously estimated for natural uranium that were
small multiples of 10-24.
“Just sort of playfully,” Frisch writes, he plugged 10-23 cm21265 into Peierls’
formula.1266 “To my amazement” the answer “was very much smaller than I
had expected; it was not a matter of tons, but something like a pound or
two.” 1267 A volume less than a golf ball for a substance so heavy as uranium.
But would that pound or two explode or fizzle?
Peierls easily produced an
estimate.
e chain reaction would have to proceed faster than the
vaporizing and swelling of the heating metal ball.
Peierls calculated the time
between neutron generations, between 1×2×4×8×16×32×64...
, to be about
four millionths of a second, much faster than the several thousandths of a
second Frisch had estimated for slow-neutron fission.
1268
en how destructive was the consequent explosion?
Some eighty
generations of neutrons—as many as could be expected to multiply before
the swelling explosion separated the atoms of U235 enough to stop the chain
reaction—still millionths of a second in total, gave temperatures as hot as
the interior of the sun, pressures greater than the center of the earth where
iron flows as a liquid.
“I worked out the results of what such a nuclear
explosion would be,” says Peierls.
“Both Frisch and I were staggered by
them.
”1269
And finally, practically: could even a few pounds of U235 be separated
from U238?
Frisch writes:
I had worked out the possible efficiency of my separation system with the
help of Clusius’s formula, and we came to the conclusion that with
something like a hundred thousand similar separation tubes one might
produce a pound of reasonably pure uranium-235 in a modest time,
measured in weeks.
At that point we stared at each other and realized that
an atomic bomb might aer all be possible.
1270
“e cost of such a plant,” Frisch adds for perspective, “would be
insignificant compared with the cost of the war.” 1271
“Look, shouldn’t somebody know about that?” Frisch then asked
Peierls.
1272 ey hastened their calculations to Mark Oliphant.
“ey
convinced me,” Oliphant testifies.1273 He told them to write it all down.
ey did, succinctly, in two parts, one part three typewritten pages, the
other even briefer.
Talking about it made them nervous, Peierls recalls (by
then it was March and the exceptional cold had given way to warmer
weather):
I remember we were writing our memorandum...
together in my room
in the Physics Lab on the ground floor; it was a fine day and the window
was open...
and while we were discussing the wording a face suddenly
appeared in the open window.
And we were a little worried!
It turned out
that just underneath the window (which was facing south) people were
growing some tomato plants, and somebody had been there bending
down inspecting what these plants were doing.
1274
e first of the two parts they titled “On the construction of a
‘superbomb’; based on a nuclear chain reaction in uranium.
”1275 It was
intended, they wrote, “to point out and discuss a possibility which seems to
have been overlooked in...
earlier discussions.” 1276 ey proceeded to cover
the same ground they had previously covered together in private, noting that
“the energy liberated by a 5 kg bomb would be equivalent to that of several
thousand tons of dynamite.” ey described a simple mechanism for arming
the weapon: making the uranium sphere in two parts “which are brought
together first when the explosion is wanted.
Once assembled, the bomb
would explode within a second or less.” 1277 Springs, they thought, might pull
the two small hemispheres together.
Assembly would have to be rapid or the
chain reaction would begin prematurely, destroying the bomb but not much
else.
A byproduct of the explosion—about 20 percent of its energy, they
thought—would be radiation, the equivalent of “a hundred tons of radium”
that would be “fatal to living beings even a long time aer the explosion.”
Effective protection from the weapon would be “hardly possible.”
e second report, “Memorandum on the properties of a radioactive
‘super-bomb,’ ” a less technical document, was apparently intended as an
alternative presentation for nonscientists.
1278 is study explored beyond
the technical questions of design and production to the strategic issues of
possession and use; it managed at the same time both seemly innocence and
extraordinary prescience:
1.
As a weapon, the super-bomb would be practically irresistible.
ere
is no material or structure that could be expected to resist the force of the
explosion....
2.
Owing to the spreading of radioactive substances with the wind, the
bomb could probably not be used without killing large numbers of
civilians, and this may make it unsuitable as a weapon for use by this
country....
3....
It is quite conceivable that Germany is, in fact, developing this
weapon....
4.
If one works on the assumption that Germany is, or will be, in the
possession of this weapon, it must be realised that no shelters are available
that would be effective and could be used on a large scale.
e most
effective reply would be a counter-threat with a similar weapon.
us in the first months of 1940 it was already clear to two intelligent
observers that nuclear weapons would be weapons of mass destruction
against which the only apparent defense would be the deterrent effect of
mutual possession.
Frisch and Peierls finished their two reports and took them to Oliphant.
He quizzed the men thoroughly, added a cover letter to their memoranda (“I
have considered these suggestions in some detail and have had considerable
discussion with the authors, with the result that I am convinced that the
whole thing must be taken rather seriously, if only to make sure that the
other side are not occupied in the production of such a bomb at the present
time”) and sent letter and documents off to Henry omas Tizard, an
Oxford man, a chemist by training, the driving force behind British radar
development, the civilian chairman of the Committee on the Scientific
Survey of Air Defense—better known as the Tizard Committee—which was
the most important British committee at the time concerned with the
application of science to war.
1279
“I have oen been asked,” Otto Frisch wrote many years aerward of the
moment when he understood that a bomb might be possible aer all, before
he and Peierls carried the news to Mark Oliphant, “why I didn’t abandon the
project there and then, saying nothing to anybody.
Why start on a project
which, if it was successful, would end with the production of a weapon of
unparalleled violence, a weapon of mass destruction such as the world had
never seen?
e answer was very simple.
We were at war, and the idea was
reasonably obvious; very probably some German scientists had had the same
idea and were working on it.” 1280
Whatever scientists of one warring nation could conceive, the scientists of
another warring nation might also conceive—and keep secret.
at early in
1939 and early 1940, the nuclear arms race began.
Responsible men who
properly and understandably feared a dangerous enemy saw their own ideas
reflected back to them malevolently distorted.
Ideas that appeared defensive
in friendly hands seen the other way around appeared aggressive.
But they
were the same ideas.
* * *
Werner Heisenberg sent his considered conclusions to the German War
Office on December 6, 1939, while Fermi and Szilard waited for the $6,000
the Briggs Uranium Committee had allocated to them for graphite studies
and Frisch prepared his pessimistic Chemical Society review.
Heisenberg
thought fission could lead to energy production even with ordinary uranium
if a suitable moderator could be found.
Water would not do, but “heavy
water [or] very pure graphite would, on the other hand, suffice on present
evidence.” e surest method for building a reactor, Heisenberg wrote, “will
be to enrich the uranium-235 isotope.
e greater the degree of enrichment,
the smaller the reactor can be made.” Enrichment—increasing the
proportion of U235 to U238—was also “the only method of producing
explosives several orders of magnitude more powerful than the strongest
explosives yet known.” 1281 (e phrase indicates Heisenberg understood the
possibility of fast-neutron fission even before Frisch and Peierls did.)
During the same period Paul Harteck in Hamburg was building a Clusius
separation tube; in December he tested it by successfully separating isotopes
of the heavy gas xenon.
He traveled to Munich at Christmastime to discuss
design improvements with Clusius, who was professor of physical chemistry
at the university there.
Auer, the thorium specialists, purveyors of gas
mantles and radioactive toothpaste, delivered the first ton of pure uranium
oxide processed from Joachimsthal ores to the War Office in January 1940.
German uranium research was thriving.
Acquiring a suitable moderator looked more difficult.
e German
scientists favored heavy water, but Germany had no extraction plant of its
own.
Harteck calculated at the beginning of the year that a coal-fired
installation would require 100,000 tons of coal for each ton of heavy water
produced, an impossibility in wartime.
e only source of heavy water in
quantity in the world was an electrochemical plant built into a sheer 1,500-
foot granite bluff beside a powerful waterfall at Vemork, near Rjukan, ninety
miles west of Oslo in southern Norway.
Norsk Hydro-Elektrisk K
vaelstofaktieselskab produced the rare liquid as a byproduct of hydrogen
electrolysis for synthetic ammonia production.1282
I.G.
Farben, the German chemical cartel assembled by Bayer’s Carl
Duisberg in the 1920s, owned stock in Norsk Hydro; learning of the War
Office’s need it approached the Norwegians with an offer to buy all the heavy
water on hand, about fiy gallons worth some $120,000, and to order more
at the rate of at least thirty gallons a month.
Norsk Hydro was then
producing less than three gallons a month, enough in the prewar years to
glut the small physics-laboratory market.
It wanted to know why Germany
needed so vast a quantity.
I.G.
Farben chose not to say.
In February the
Norwegian firm refused either to sell its existing stock or to increase
production.
Heavy water also impressed the French team, a fact Joliot pased on to the
French Minister of Armament, Raoul Dautry.
When Dautry heard about the
German bid for Norsk Hydro’s supply he decided to win the water for
France.
A French bank, the Banque de Paris et des Pays Bas, controlled a
majority interest in the Norwegian company and a former bank officer,
Jacques Allier, was now a lieutenant in Dautry’s ministry.
1283 Dautry briefed
the balding, bespectacled Allier with Joliot on hand on February 20: the
minister wanted the lieutenant to lead a team of French secret-service agents
to Norway to acquire the heavy water.
Allier slipped into Oslo under an assumed name and met with the general
manager of Norsk Hydro at the beginning of March.
e French officer was
prepared to pay up to 1.5 million kroner for the water and even to leave half
for the Germans, but once the Norwegian heard what military purpose the
substance might serve he volunteered his entire stock and refused payment.
e water, divided among twenty-six cans, le Vemork by car soon
aerward on a dark midnight.
From Oslo Allier’s team flew it to Edinburgh
in two loads—German fighters forced down for inspection a decoy plane
Allier had pretended to board at the time of the first loading—and then
transported it by rail and Channel ferry to Paris, where Joliot prepared
through the winter and spring of the phony war to use it in both
homogeneous and heterogeneous uranium-oxide experiments.
Nuclear research in the Soviet Union during this period was limited to
skillful laboratory work.
Two associates of Soviet physicist Igor Kurchatov
reported to the Physical Review in June 1940 that they had observed rare
spontaneous fissioning in uranium.
“e complete lack of any American
response to the publication of the discovery,” writes the American physicist
Herbert F.
York, “was one of the factors which convinced the Russians that
there must be a big secret project under way in the United States.” 1284 It was
not yet big, but by then it had begun to be secret.
Japanese studies toward an atomic bomb began first within the
military.
1285 e director of the Aviation Technology Research Institute of
the Imperial Japanese Army, Takeo Yasuda, a lieutenant general and an alert
electrical engineer, conscientiously followed the international scientific
literature that related to his field; in the course of his reading in 1938 and
1939 he noticed and tracked the discovery of nuclear fission.1286 In April
1940, foreseeing fission’s possible consequences, he ordered an aide who was
scientifically trained, Lieutenant Colonel Tatsusaburo Suzuki, to prepare a
full report.
Suzuki went to work with a will.
* * *
Niels Bohr had returned from Princeton to Copenhagen at the beginning of
May 1939, preoccupied with the gathering European apocalypse.
His friends
had urged him to send for his family and remain in the United States.
He
had not been tempted.
Refugees still escaping from Germany and now
fleeing Central Europe as well needed him; his institute needed him;
Denmark needed him.
Hitler proposed on May 31 to compromise the
neutrality of the Scandinavian countries with nonagression pacts.
e
pragmatic Danes alone accepted, fully aware the pact was worthless and
even demeaning but unwilling to invite invasion for a paper victory.
By
autumn, when the John Wheelers offered to shelter one of Bohr’s sons in
Princeton for the duration of the conflict, Bohr reserved the offer against
future need.
“We are aware that a catastrophe might come any day,” he wrote
in the midst of Poland’s agony.1287
Catastrophe for Denmark waited until April 1940 and came then with
brutal efficiency.
Bohr was lecturing in Norway.
e British had announced
their intention to mine Norwegian coastal waters against shipment of
Norwegian iron ore to Nazi Germany.
On the final evening of his lecture
tour, April 8, Bohr dined with the King of Norway, Haakon VII, and found
King and government lost in gloom at the prospect of a German attack.
Aer dinner he boarded the night train for Copenhagen.
A train ferry
carried the cars across the Óresund at night to Helsingør while the
passengers slept.
Danish police pounding on compartment doors woke
them to the news: the Germans had invaded not only Norway but Denmark
as well.
Two thousand German troops hidden in coal freighters moored near
Langelinie, the Copenhagen pier of Hans Christian Andersen’s Little
Mermaid, had stormed ashore in the early morning, so unexpected a sight
that night-shi workers bicycling home thought a motion picture was being
filmed.
A major German force had marched north through Schleswig-
Holstein onto the Danish peninsula as well, crossing the border before
dawn.
German aircra marked with black crosses dominated the air.
German warships commanded the Kattegat and Skagerrak passages that
open Denmark and southern Norway to the North Sea.
e Norwegians fought back, determined that their King, court and
parliament must escape to exile.
e Danes, in their flat country where
Panzers might roll, did not.
Rifle fire crackled in the streets of Copenhagen
in the early morning, but King Christian X ordered an immediate ceasefire,
which took effect at 6:25 A.M.
By the time Bohr’s train arrived in the capital
city what Churchill would call “this ruthless coup” was complete, the streets
littered with green surrender leaflets, the King preparing to receive the
German chief of staff.1288 Danish resistance would be dedicated and
effective, but it would take less suicidal forms than open battle with the
Wehrmacht.
e American Embassy quickly passed word that it could guarantee the
Bohrs safe passage to the United States.
Bohr again chose duty.
His
immediate concern was to burn the files of the refugee committee that had
helped hundreds of emigres to escape to exile.
“It was characteristic of Niels
Bohr,” his collaborator, Stefan Rozental, writes, “that one of the first things
he did was to contact the Chancellor of the University and other Danish
authorities in order to protect those of the staff at the Institute whom the
Germans might be expected to persecute.
”1289 ose were Poles first of all,
but Bohr also sought out government leaders to argue for concerted Danish
resistance to any German attempt to install anti-Semitic laws in Denmark.
He even found time on the day of the occupation to worry about the large
gold Nobel Prize medals that Max von Laue and James Franck had given
him for safekeeping.
1290 Exporting gold from Germany was a serious
criminal offense and their names were engraved on the medals.1291 , 1292
George de Hevesy devised an effective solution—literally: he dissolved the
medals separately in acid.
As solutions of black liquid in unmarked jars they
sat out the war innocently on a laboratory shelf.
Aerward the Nobel
Foundation recast them and returned them to their owners.
Norsk Hydro was a prime German objective and there was heavy fighting
around Rjukan, which held out until May 3, the last town in southern
Norway to surrender.
en a management under duress reported to Paul
Harteck that its heavy-water facility, the Vemork High Concentration Plant,
could be expanded to increase production of the ideal neutron moderator to
as much as 1.5 tons per year.
* * *
“What I should like,” Henry Tizard wrote Mark Oliphant aer he had
studied the Frisch-Peierls memoranda, “would be to have quite a small
committee to sit soon to advise what ought to be done, who should do it,
and where it should be done, and I suggest that you, omson, and say
Blackett, would form a sufficient nucleus for such a committee.” omson
was G.
P.
omson, J.J.’s son, the Imperial College physicist who had ordered
up a ton of uranium oxide the previous year to study and felt ashamed at the
absurdity.
He had concluded aer neutron-bombardment experiments that
a chain reaction in natural uranium was unlikely and a war project therefore
impractical.
Tizard, who had been skeptical to begin with and had taken
omson’s conclusions as support for his skepticism, appointed omson
chairman of the small committee; James Chadwick, now at Liverpool, his
assistant P.
B.
Moon and Rutherford protege John Douglas Cockcro were
added to the list.
Blackett was busy with other war work, although he would
join the committee later.
e group met informally for the first time on April
10 in the Royal Society’s quarters at Burlington House.
It probably met as much to hear a visitor, the ubiquitous Jacques Allier of
the Banque de Paris and the French Ministry of Armament, as to discuss the
Frisch-Peierls work.
Allier warned the British physicists about the German
interest in heavy-water production and bid for collaboration on nuclear
research between Britain and France.
Only then, omson notes in the
minutes he kept, did they consider “the possibility of separating isotopes...
and it was agreed that the prospects were sufficiently good to justify small-
scale experiments on uranium hexafluoride [a gaseous uranium
compound].” ey proposed rather ungenerously to remind Frisch to avoid
“any possible leakage of news in view of the interest shown by the
Germans.
”1293 ey were willing to inform him that his memorandum was
being considered but not to supply details.
(Peierls’ name seems not yet to
have made an impression on omson, and Tizard apparently retained the
second Frisch-Peierls memorandum in his files.) “We entered the project
with more scepticism than belief,” the committee would report later, “though
we felt it was a matter which had to be investigated.” 1294 omson’s minutes
make that skepticism evident.
Tizard for his part wrote Lindemann’s brother
Charles, a science adviser to the British Embassy in Paris, that he considered
the French “unnecessarily excited” about the perils of German nuclear
research.
1295 “I still...
think that [the] probability of anything of real military significance is very low,” he estimated in a note written the same
week to the British War Cabinet staff.
1296
It might have been as unpromising a start as the first meeting of the Briggs
Uranium Committee had been, but the men on the omson committee
were active, competent physicists, not military ordnance specialists, and
whatever their initial skepticism they understood where the numbers Frisch
and Peierls had used came from and what they might mean.
At a second
meeting on April 24 omson recorded laconically that “Dr.
Frisch
produced some notes to show that the uranium bomb was feasible.” 1297
Many years later Oliphant recalled a more expansive response: “e
Committee generally was electrified by the possibility.” Chadwick’s good
opinion helped.
He had just begun exploring fast-neutron fission himself
with his new Liverpool cyclotron, the first in England, when he saw the
Frisch-Peierls memorandum.
At the April 24 meeting he awarded the
emigres’ work chagrined confirmation: he “was embarrassed,” says Oliphant,
“confessing that he had reached similar conclusions, but did not feel justified
in reporting them until more was known about the neutron cross sections
from experiments.
Peierls and Frisch had used calculated values.
However,
this confirmatory evidence led the Committee to pay great attention to the
development of techniques for...
separation.” 1298
Chadwick agreed to undertake the necessary studies.
For several more
weeks, until their protests through Oliphant registered with omson,
Frisch and Peierls would be walled off from their own secrets.
But work
toward a bomb of chain-reacting uranium was now fairly begun, and this
time it had found the right—fast—track.
* * *
Szilard chafed.
e months aer the first Uranium Committee meeting
became “the most curious period of my life.” No one called.
“We heard
nothing from Washington at all....
I had assumed that once we had
demonstrated that in the fission of uranium neutrons are emitted, there
would be no difficulty in getting people interested; but I was wrong.
”1299 e
Uranium Committee’s November 1 report had in fact been languishing in
Roosevelt’s files; Watson finally decided on his own in early February 1940
to bring it up again.1300 He asked Lyman Briggs if he had anything to add.
Briggs reported the transfer, finally, of the $6,000 for Fermi’s work on
neutron absorption in graphite.
at was “a crucial undertaking,” Briggs
said; he imagined it would determine “whether or not the undertaking has a
practical application.
”1301 He proposed to wait for results.
Something other than Briggs’ penurious methodology triggered a new
burst of activity from Szilard.
He had spent the winter preparing a thorough
theoretical study, “Divergent chain reactions in systems composed of
uranium and carbon”—divergent in this case meaning chain reactions that
continue to multiply once begun (the document’s first footnote, numbered
zero, cited “H.1302 G.
Wells, e World Set Free [1913]”).
Early in the new
year Joliot’s group reported a uranium-water experiment that “seemed to
come so close to being chain-reacting,” says Szilard, “that if we improved the
system somewhat by replacing water with graphite, in my opinion we should
have gotten over the hump.” He arranged lunch with Fermi to discuss the
French paper.
“I asked him, ‘Did you read Joliot’s paper?’ He said he did.
I
asked him, ‘What did you think of it?’ and Fermi said, ‘Not much.’ ” Szilard
was furious.
“At which point I saw no reason to continue the conversation
and went home.
”1303
He traveled again to Princeton to see Einstein.
ey worked up another
letter and sent it under Einstein’s signature to Sachs.
It emphasized the secret
German uranium research at the Kaiser Wilhelm Institutes, about which
they had learned from the physical chemist Peter Debye, the 1936 Nobel
laureate in chemistry and director of the physics institute at Dahlem, who
had been expelled recently to the United States, ostensibly on leave of
absence, when he refused to give up Dutch citizenship and join the Nazi
Reich.
Sachs sent the Einstein letter on to Pa Watson for FDR.
But Watson
thought it sensible to check first with the Uranium Committee.
Adamson
responded, echoing Briggs: everything depended on the graphite
measurements at Columbia.
Watson proposed to wait for the official report.
Sachs may have rebutted; Roosevelt wrote the gadfly economist on April 5
emphasizing that the Briggs committee was “the most practical method of
continuing this research” but also calling for another committee meeting
that Sachs might attend.1304 Briggs dutifully scheduled it for Saturday
aernoon, April 27.
In the meantime another development intervened.
Alfred Nier at the
University of Minnesota had gone to work, aer Fermi wrote urging him
again to do so, to prepare to separate measurable samples of U235 and
U238.
John Dunning sent him uranium hexafluoride, a highly corrosive
compound that is a white solid at room temperature but volatilizes to a gas
when heated to 140°F.
“I worked with this for a couple of months in late
1939,” Nier remembers.1305 Unfortunately the gas was too volatile; it
dispersed through Nier’s three-foot glass spectrometer tube despite the best
efforts of his vacuum pump to clear it and contaminated the collector plates:
Finally I said, “is won’t do.” A new instrument was built in about 10
days in February, 1940.
Our glass blower bent the horseshoe-shaped mass
spectrometer tube for me; I made the metal parts myself.
As a source of
uranium, I used the less volatile uranium tetrachloride and tetrabromide
le over from [his earlier] Harvard experiments.
e first separation of U-
235 and U-238 was actually accomplished on February 28 and 29, 1940.
It
was a leap year, and on Friday aernoon, February 29,1 pasted the little
samples [collected on nickel foil] on the margin of a handwritten letter
and delivered them to the Minneapolis Post Office at about six o’clock.
e letter was sent by airmail special delivery and arrived at Columbia
University on Saturday.
I was aroused early Sunday morning by a long-
distance telephone call from John Dunning [who had worked through the
night bombarding the samples with neutrons from the Columbia
cyclotron].
e Columbia test of the samples clearly showed that U-235
was responsible for the slow neutron fission of uranium.
e demonstration vindicated Bohr’s hypothesis, but it also led Briggs to
even greater suspicion of the value of natural uranium; it was “very
doubtful,” he reported to Watson on April 9 “whether a chain reaction can
be established without separating 235 from the rest of the uranium.” 1306
Nier, Dunning and their collaborators Eugene T.
Booth and Aristide von
Grosse had written much the same thing in the Physical Review on March
15: “ese experiments emphasize the importance of uranium isotope
separation on a larger scale for the investigation of chain reaction
possibilities in uranium.” 1307 But isotope separation was Dunning’s approach
to the problem in the first place and his enthusiasm as well; the slow-
neutron finding hardly ruled out the Fermi-Szilard system.
More misleading
may have been the measurements Nier and the Columbia team published on
April 15 using larger (but still microscopic) samples: “Furthermore, the
number of fissions/microgram of U238 observed under these neutron
intensity conditions, is sufficient to account for practically all the fast
neutron fission observed in unseparated U.” 1308 e statement was correct
within the limits of measurement for such small samples, but its wording
seems to deprecate U235 fast-neutron fission.
In fact, Nier had not collected
enough U235 to allow Columbia to measure that possibility.
All anyone
knew by then was that the U235 cross section for fast-neutron fission was
less than the isotope’s cross section for slow-neutron fission.
But that cross
section, as the first Nier/Columbia paper reported, was a whopping 400 to
500 × 10−24cm2.
1309
Predictably, then, when the Uranium Committee met on April 27, with
Sachs, Pegram, Fermi, Szilard and Wigner in attendance, it listened to the
renewed debate, squared its shoulders at Sachs’ exhortation to plunge ahead
—and never wavered in its adamant conviction that a large-scale uranium-
graphite experiment should await the outcome of Fermi’s graphite
measurements.
* * *
Now that the $6,000 had been paid, Columbia was able to buy the graphite
Szilard had tracked down for Fermi’s use.
“Cartons of carefully-wrapped
graphite bricks began to arrive at the Pupin Laboratory,” Herbert Anderson
remembers, four tons in all.
“Fermi returned to the chain reaction problem
with enthusiasm.
is was the kind of physics he liked best.
Together we
stacked the graphite bricks in a neat pile.
We cut narrow slots in some of the
bricks for the rhodium foil detectors we wanted to insert, and soon we were
ready to make measurements.” 1310
“So the physicists on the seventh floor of Pupin Laboratories started
looking like coal miners,” adds Fermi, “and the wives to whom these
physicists came back tired at night were wondering what was
happening.
”1311
e arrangement was designed to determine how far neutrons from a
radon-beryllium source set in paraffin on the floor under the graphite
column would diffuse up the column through the graphite aer first slowing
down in scattering collisions: the farther the neutrons traveled, the smaller
was carbon’s absorption cross section and therefore the better moderator it
would be.
e Pupin seventh floor became a racetrack like the second floor
of the institute in Rome.
Anderson describes the scene:
A precise schedule was followed for each measurement.
With the
rhodium in place in the graphite, the source was inserted in its position
inside the pile and removed aer a one-minute exposure.
To get the
rhodium foil under the Geiger counter in the allotted 20 seconds [because
its induced half-life is only 44 seconds] took coordination and some fast
legwork.
e division of labor was typical.
I removed the source on signal;
Fermi, stopwatch in hand, grabbed the rhodium and raced down the hall
at top speed.
He had just enough time to place the foil carefully into
position, close the lead shield and, at the prescribed moment, start the
count.
en with obvious satisfaction at seeing everything go right, he
would watch the flashing lights on the scaler, tapping his fingers on the
bench in time with the clicking of the register.
Such a display of the
phenomenon of radioactivity never failed to delight him.
1312
e absorption cross section, as Fermi and Anderson subsequently
calculated it, proved usefully small: 3 × 10−27cm2.1313 And could be made
smaller still, they thought, with purer graphite.
e measurement strongly
supported Fermi’s and Szilard’s plan to attempt to induce a slow-neutron
chain reaction in natural uranium.
But while such a plan might demonstrate a potential future source of
power, the American scientists and administrators who were advising Briggs
could not yet identify any military use.
In April the British omson
committee asked A.
V.
Hill, a scientific adviser to the British Embassy in
Washington, to find out what the Americans were doing about fission.
According to the official history of the British atomic energy program, Hill
talked to unidentified “scientists of the Carnegie Institution,” whose
opinions he reported pungently:1314
It is not inconceivable that practical engineering applications and war use
may emerge in the end.
But I am assured by American colleagues that
there is no sign of them at present and that it would be a sheer waste of
time for people busy with urgent matters in England to turn to uranium
as a war investigation.
If anything likely to be of war value emerges they
will certainly give us a hint of it in good time.
A large number of
American physicists are working on or interested in the subject; they have
excellent facilities and equipment: they are extremely well disposed
towards us: and they feel that it is much better that they should be
pressing on with this than that our people should be wasting their time on
what is scientifically very interesting, but for present practical needs
probably a wild goose chase.
1315
e opinion from the Carnegie may have been hardheaded, but it was
based on more than prejudice.
Roberts, Hafstad and fellow DTM physicist
Norman P.
Heydenburg had improved their measurements of cross sections
for fast-neutron fission, scattering and capture in natural uranium.
Using
their numbers, Edward Teller in one of the many calculations he made
during this period arrived at a critical mass in excess of thirty tons, the same
order of magnitude as Perrin and Peierls had calculated before him.
1316
With only slightly more pessimistic assumptions Roberts concluded that
“the cross-section for capture [in natural uranium] is sufficiently large that it
now seems impossible for a fast-neutron chain reaction to occur, even in an
infinitely large block of pure uranium.” 1317 By the spring of 1940
experiments at Columbia and the DTM had thus ruled out both slow- and
significant fast-neutron fission in U238 and ruled in slow-neutron fission in
U235.
e asymmetry might have been a clue.
No one picked it up.
* * *
Since at least the time of Einstein’s first letter to FDR, Edward Teller had
debated within himself the morality of weapons work.
His life had twice
been cruelly uprooted by totalitarianism.
He understood Germany’s
frightening technological advantages at the outset of the war.
“I came to the
United States in 1935,” he notes.
“...
e handwriting was on the wall.
At
that time, I believed that Hitler would conquer the world unless a miracle
happened.” 1318 But pure science still pacified him.
“To deflect my attention
from physics, my full-time job which I liked, to work on weapons, was not
an easy matter.
And for quite a time I did not make up my mind.” 1319
e accidental juxtaposition of two events led him to decision.
“In the
spring of 1940 it was announced that President Roosevelt would speak to a
Pan American Scientific Congress in Washington, and as one of the
professors of George Washington University I was invited.
I did not intend
to go.
”1320 e other event of that crucial day, May 10, 1940, reversed his
intention: the phony war abruptly ended.
With seventy-seven divisions and
3,500 aircra Germany without declaration or warning invaded Belgium,
the Netherlands and Luxembourg to make way for the invasion of France.
Teller thought Roosevelt might speak to that outrage.
In his voluntary
prewar isolation he had never bothered, Teller says, to visit the Capitol or
listen to one of FDR’s radio talks or otherwise involve himself in the political
life of his adopted country, but he wanted now to see the President of the
United States in person.
1321
Alone among the scientists at the congress Teller knew about the Einstein
letter.
It was a direct link, he was an emotional man and the encounter with
Roosevelt was eerily personal: “We had never met, but I had an irrational
feeling he was talking to me.” 1322 e President mentioned the German
invasion, its challenge to “the continuance of the type of civilization” the
people of the Americas valued, the distances of the modern world shortened
by modern technology to timetables that removed the “mystic immunity”
Americans once felt from European war.1323 “en he started to talk about
the role of the scientist,” Teller recalls, “who has been accused of inventing
deadly weapons.
1324 He concluded: ‘If the scientists in the free countries will
not make weapons to defend the freedom of their countries, then freedom
will be lost.’ ” Teller believed Roosevelt was not proposing what scientists
may do “but something that was our duty and that we must do—to work out
the military problems, because without the work of the scientists the war
and the world would be lost.” 1325
Teller’s memory of Roosevelt’s speech differs from its text.
e President
said that most people abhor “conquest and war and bloodshed.
”1326 He said
that the search for truth was a great adventure but that “in other parts of the
world, teachers and scholars are not permitted” that search—an observation
of which Teller had personal knowledge.
And then, cannily, Roosevelt
offered absolution in advance for war work:
You who are scientists may have been told that you are in part responsible
for the debacle of today...
but I assure you that it is not the scientists of
the world who are responsible....
What has come about has been caused
solely by those who would use, and are using, the progress that you have
made along lines of peace in an entirely different cause.
“My mind was made up,” Teller reports, “and it has not changed since.
”1327
* * *
Vannevar Bush made a similar choice that spring.
e sharp-eyed Yankee
engineer, who looked like a beardless Uncle Sam, had le his MIT vice
presidency for the Carnegie Institution in the first place to position himself
closer to the sources of government authority as war approached.
Karl
Compton had offered to move up to chairman of the MIT corporation and
give him the presidency to keep him, but Bush had larger plans.
As a young man, with a doctorate in engineering behind him jointly from
MIT and Harvard earned in one intense year, Bush in 1917 had gone
patriotically to work for a research corporation developing a magnetic
submarine detector.
e device was effective, and one hundred sets got built;
but because of bureaucratic confusion they were never put to use against
German submarines.
“at experience,” Bush writes in a memoir, “forced
into my mind pretty solidly the complete lack of proper liaison between the
military and the civilian in the development of weapons in time of war, and
what that lack meant.” 1328
In Washington aer the invasion of Poland the Carnegie president
gathered with a group of fellow science administrators—Frank Jewett,
president of Bell Telephone Laboratories and the National Academy of
Sciences; James Bryant Conant, the young president of Harvard, a
distinguished chemist; Richard Tolman of Caltech, the theoretician who had
wooed Einstein; Karl Compton—to worry about the approaching conflict:
It was during the period of the “phony” war.
We were agreed that the war
was bound to break out into an intense struggle, that America was sure to
get into it in one way or another sooner or later, that it would be a highly
technical struggle, that we were by no means prepared in this regard, and
finally and most importantly, that the military system as it existed...
would never fully produce the new instrumentalities which we would
certainly need.
1329
ey devised a national organization to do the job.
Bush had learned his
way around Washington and took the lead.
e organization Bush wanted
needed independent authority.
He thought it should report directly to the
President rather than through military channels and should have its own
source of funds.
He draed a proposal.
en he arranged an introduction to
Harry Hopkins.
A small-town Iowa boy, idealistic and energetic, Harry Lloyd Hopkins had
fallen into New York social work aer four years at Grinnell and won
appointment at the beginning of the Depression administering emergency
state relief.
When the governor of New York was elected President, Hopkins
moved with Roosevelt to Washington to help out with the New Deal.
He ran
the vast Works Progress Administration, then took over as Secretary of
Commerce.
His performance moved him closer and closer to the President,
who picked up talent wherever he could find it; as war approached,
Roosevelt invited Hopkins to dinner at the White House one evening and
moved the man in for the duration as his closest adviser and aide.
Hopkins
was tall, a chain smoker and emaciated to the point of cachexia, his ghastly
health the result of cancer surgery that took most of his stomach and le
him unable to absorb much protein and therefore slowly starving to death.
He kept an office in the White House basement but usually worked out of a
cluttered bedroom suite—the Lincoln Bedroom—down the hall from FDR’s.
When Bush met Hopkins, though the presidential aide was a liberal
Democrat and the Carnegie president an admirer of Herbert Hoover and a
self-styled Tory, “something meshed,” writes Bush, “and we found we spoke
the same language.” 1330 Hopkins had a scheme for an Inventors Council.
Bush countered with his more comprehensive National Defense Research
Council.
“Each of us was trying to sell something to the other.” 1331 Bush
won.
Hopkins liked his plan.
In early June Bush made the rounds of Washington touching bases: the
Army, the Navy, Congress, the National Academy of Sciences.
On June 12
“Harry and I then went in to see the President.
It was the first time I had met
Franklin D.
Roosevelt....
I had the plan for N.D.R.C.
in four short
paragraphs in the middle of a sheet of paper.
e whole audience lasted less
than ten minutes (Harry had no doubt been there before me).
I came out
with my ‘OK-FDR’ and all the wheels began to turn.”
e National Defense Research Council immediately absorbed the
Uranium Committee.
at had been part of its purpose.
Briggs was a
cautious and frugal man, but his committee had also lacked the authority of
a source of funds independent of the military.
e white-haired director of
the National Bureau of Standards would continue to be responsible for
fission work.
He would report now to James Bryant Conant, Harvard’s wiry
president, boyish in appearance but in practice cool and reserved, whom
Bush had enlisted as soon as FDR authorized the new council.
e NDRC gave research in nuclear fission an articulate lobby within the
executive branch.
But though Bush and Conant felt challenged by German
science—“the threat of a possible atomic bomb,” writes Bush, “was in all our
minds”—both men, concerned about scarce scientific resources, were
initially more interested in proving the impossibility of such a weapon than
in rushing to build one: the Germans could not do what could not be
done.1332 , 1333 When Briggs wrapped up his pre-NDRC committee work in a report to Bush on July 1 he asked for $140,000, $40,000 of it for research on
cross sections and other fundamental physical constants, $100,000 for the
Fermi-Szilard large-scale uranium-graphite experiment (the military had
decided to grant $100,000 on its own through the Naval Research
Laboratory to isotope-separation studies).
Bush allotted Briggs only the
$40,000.
Once again Fermi and Szilard were le to bide their time.
* * *
Winston Churchill had accepted George VI’s invitation to form a
government upon Neville Chamberlain’s resignation the day Germany
invaded the Lowlands; he shouldered the prime ministership calmly but felt
the somber weight of office.
C.
P.
Snow recalls a more paradoxical mood:
I remember—I shall not forget it while I live—the beautiful, cloudless,
desperate summer of 1940....
Oddly enough, most of us were very happy
in those days.
ere was a kind of collective euphoria over the whole
country.
I don’t know what we were thinking about.
We were very busy.
We had a purpose.
We were living in constant excitement, usually, if we
examined the true position, of an unpromising kind.
In one’s realistic
moments, it was difficult to see what chance we had.
But I doubt if most
of us had many realistic moments, or thought much at all.
We were all
working like mad.
We were sustained by a surge of national emotion, of
which Churchill was both symbol and essence, evocator and voice.1334
Not only native-born Englishmen felt that surge.
So did the emigré
scientists whom Britain had sheltered.
Franz Simon, an outstanding chemist
whom Frederick Lindemann had extracted from Germany in 1933 for the
Clarendon, wrote his old friend Max Born on the eve of the Battle of France
that he longed to “use my whole force in the struggle for this country.
”1335,
1336 ough he may not yet have realized it, Simon’s opportunity had already
arrived.
Early in the year, when Frisch and Peierls were first beginning to
discuss the ideas that would lead to their important memoranda, Peierls had
consulted Simon about methods of isotope separation.
Frisch had chosen to
work with gaseous thermal diffusion—his Clusius tube—because it seemed
to him the simplest method, but Simon had begun then to think about other
systems.
Half a dozen approaches had been tried in the past.
You couldn’t
spit on the floor without separating isotopes, Simon joked; the problem was
to collect them.1337 He wanted to find a method adaptable to mass
production, because with a 1:139 isotope ratio, uranium separation would
have to proceed on a vast scale, as Frisch’s calculation of 100,000 Clusius
tubes demonstrated.
Frisch dramatized the difficulty with a simile: “It was
like getting a doctor who had aer great labour made a minute quantity of a
new drug and then saying to him: ‘Now we want enough to pave the
streets.’ ” 1338
e surge of national emotion sustained Mark Oliphant as well, and in
that mood he found even less patience than usual for obstructive rules.
When P.
B.
Moon questioned the assumption that gaseous thermal diffusion
was the method of choice for isotope separation, he won no encouragement
from the omson committee, but back in Birmingham Oliphant simply
told him to go ahead and talk it over with Peierls.
“Within a week or two,”
writes Moon, “Peierls identified ordinary diffusion as a logically superior
process and wrote directly to omson on the matter.” 1339 Peierls proposed
that the omson committee consult with Simon, the best man around.
e
committee hesitated, even though Simon was a naturalized citizen.
Oliphant
then authorized Peierls out of hand to visit Simon at Oxford.
Simon in the meantime had been working to convert a skeptical
Lindemann.
At Simon’s suggestion Peierls had written to Lindemann on
June 2.
Together at Oxford later in June they approached Lindemann in
person.
“I do not know him sufficiently well to translate his grunts correctly,”
Peierls reported of the meeting.
But he felt sure he had “convinced him that
the whole thing ought to be taken seriously.” 1340
Like Peierls, Simon had settled on “ordinary” gaseous diffusion (as
opposed to gaseous thermal diffusion) as the best method of isotope
separation aer winnowing through the alternatives.
Gases diffuse through
porous materials at rates that are determined by their molecular weight,
lighter gases diffusing faster than heavier gases.
Francis Aston had applied
this principle in 1913 when he separated two isotopes of neon by diffusing a
mixed sample several thousand times over and over through pipe clay—that
is, unglazed bisque of the sort used to make clay pipes.
ick materials like
pipe clay worked too slowly to be effective at factory scale; Simon sought a
more efficient mechanism and concluded that a metal foil punctured with
millions of microscopic holes would work faster.
Divide a cylinder down its
length with such a foil barrier, pump a gas of mixed isotopes into one side of
the divided cylinder, and gas would diffuse through the barrier as it flowed
from one end of the cylinder to the other.
Compared to the gas le behind,
the gas that diffused through the barrier would be selectively enriched in
lighter isotopes.
In the case of uranium hexafluoride the enrichment factor
would be slight, 1.0043 under ideal conditions.
But with enough repetitions
of the process any degree of enrichment was possible, up to nearly 100
percent.
e immediate problem, Simon saw, was barrier material.
e smaller the
holes, the higher the pressures a separation system could sustain, and the
higher the pressure, the smaller the equipment could be.
Whatever the
material, it would have to resist corrosion by uranium hexafluoride—“hex,”
they were beginning to call it, not necessarily in tribute to its evil contrarities
—or the gas would clog its microscopic pores.
One morning that June, inspired, Simon took a hammer to a wire strainer
he found in his kitchen.1341 He carried the results to the Clarendon and
called together two of his assistants—a Hungarian, Nicholas Kurti, and a big
Rhodes scholar from Idaho, H.
S.
Arms.
“Arms, Kurti,” Simon announced,
holding up the strainer, “I think we can now separate the isotopes.
”1342 He
had hammered the wires flat in demonstration, reducing the spaces between
to pinholes.
“e first thing we used,” Kurti recalls, “was ‘Dutch cloth,’ as I think it is
called—a very fine copper gauze which has many hundreds of holes to the
inch.” 1343 e assistants hammered the holes even finer by hand.
ey tested
the copper barrier not with hex but with a mixture of water vapor and
carbon dioxide, “in other words something much like ordinary
sodawater”—the first in an urgent series of experiments carried out through
the summer and fall to study materials, pore size, pressures and other basic
parameters preliminary to any equipment design.
In late June G.
P.
omson gave his committee a new name to disguise its
activities: MAUD.
e initials appear to form an acronym but do not.
ey
arrived as a mysterious word in a cable from Lise Meitner to an English
friend: MET NIELS AND MARGRETHE RECENTLY BOTH WELL BUT UNHAPPY ABOUT
EVENTS PLEASE INFORM COCKCROFT AND MAUD RAY KENT.1344 Meitner’s friend
passed the message to Cockcro, who decided, he wrote Chadwick, that
MAUD RAY KENT was “an anagram for ‘radium taken.’ is agrees with other
information that the Germans are getting hold of all the radium they
can.” 1345 omson borrowed the first word of Cockcro’s mysterious
anagram for a suitably misleading name.
e committee members did not
learn until 1943 that Maud Ray was the governess who had taught Bohr’s
sons English; she lived in Kent.
e war crossed the Channel first in the air.
As a result of the German
bombing of Warsaw in the autumn of 1939, an act Germany represented as
tactical because the Polish city was heavily fortified, the British Air Ministry
had repudiated its pledge to refrain from strategic bombing.1346 But neither belligerent was eager to exchange bombing raids, and although nightly
blackouts added inconvenience and apprehension to the wartime burden of
the people of both nations, the implicit truce held until mid-May 1940.
en
within a week two events triggered British action.
German raiders targeted
for French airfields at Dijon lost their way and bombed the southern
German city of Freiburg instead, killing fiy-seven people; the German
Ministry of Propaganda brazenly denounced the bombing as British or
French and threatened fivefold retaliation.
Blacker and more violent non
sequitur destroyed the city center of Rotterdam.
Dutch forces were holding
out stubbornly as late as May 14 in the northern section of that old
Netherlands port.
e German commanding general ordered a “short but
devastating air raid” that he hoped might decide the battle.
1347 Negotiations
with the Dutch advanced, the air raid was canceled, but the abort message
arrived too late to stop half the hundred Heinkel lll’s ordered into action
from dropping 94 tons of bombs.
e bombs started massive fires in stores
of fats and margarine.
e first official Dutch statement, issued from the
embassy in Washington, placed casualties in the devastated city at 30,000,
and the Western democracies responded with outrage.
Actual deaths totaled
about 1,000; some 78,000 people went homeless.
e British retaliated on May 15 by dispatching ninety-nine bombers to
attack railway centers and supply depots in the Ruhr.
Busy with the Battle of
France, Hitler did not immediately strike back, but he issued a directive that
prepared the way.
He ordered the Luwaffe “to undertake a full-scale
offensive against the British homeland as soon as sufficient forces are
available.
”1348
e initial German air attack, the Battle of Britain, began in mid-August: a
month of ferocious daylight contests between the Luwaffe and British
Fighter Command for air supremacy in advance of Operation Sea Lion,
Germany’s planned cross-Channel invasion.
It was not yet an attack on
cities.
British airfields and aircra factories were primary targets.
Hitler had
reserved for himself the decision to bomb London, just as the Kaiser had
done before him.
1349 Cities would soon go on the targeting list, however; the
Luwaffe was scheduled to raid Liverpool at night on August 28.
Accident
again intervened: German bombers aiming for oil storage tanks along the
ames overflew their targets on August 24 and bombed central London
instead.
Churchill immediately retaliated, hurling four bombing raids in one week
at Berlin.
ey accomplished little physical damage but incited Hitler to
hysterical revenge:
And if the British air force drops two or three or four thousand kilograms
of bombs, then we will drop in a single night 150,000, 180,000, 230,000,
300,000, 400,000, a million kilograms.
If they announce that they will
attack our cities on a large scale, then we shall wipe their cities out!
1350
e Luwaffe was losing the Battle of Britain in any case, taking
unacceptable losses—some 1,700 German aircra compared to about 900
British.
Night bombing would alleviate the losses, curtaining the bombers in
dark asylum.
But night bombing was notably less accurate than daylight
bombing in those days before effective radar and required correspondingly
larger targets.
Cities and their civilian populations thus fell victim partly by
default, because the technology necessary for more accurate targeting was
not yet at hand.
In any case terror was a weapon that Hitler especially prized,
the destruction of what he called the enemy’s “will-to-resist,” and early in
September he told his Sea Lion planners that “a systematic and long-drawn-
out bombardment of London might produce an attitude in the enemy which
will make Sea Lion unnecessary.” 1351, 1352 He ordered the bombardment.
Since it rained from the skies for months, it was hardly Blitzkrieg, lightning
war, but the citizens exposed beneath it were not in the mood for fine
distinctions, and they soon named it the Blitz.
Gresham’s Law operated with air raid shelters as it operates with good and
bad money: the basements of better department stores like Dickens and
Jones, where clerks carried around refreshments—chocolates and ice cream
—filled up first.
Because the bombing followed regularly, night aer night,
Londoners had time to get used to it, but adjustment could go either way,
the confident beginner slowly unraveling, the frightened beginner moving
beyond fear.
More Londoners by far lived out the dangerous raids in their homes than
in shelters: 27 percent fled to corrugated-iron Anderson shelters in back
gardens, 9 percent to street shelters, only 4 percent into the Tube.
By mid-
November 13,700 tons of high explosives had fallen and 12,600 tons of
incendiary canisters, an average of 201 tons per night; for the entire Blitz,
September to May, the total tonnage reached 18,800—18.8 kilotons by
modern measure, spread across nine months.
1353 London civilian deaths in
1940 and 1941 totaled 20,083, civilian deaths elsewhere in Britain 23,602, for
a total death by Blitz in the second and third year of the war (about which
the United States was still officially neutral) of 43,685.1354 Aer that the
bombing went the other way.
Only twenty-seven Londoners lost their lives
to bombs in 1942.
At Oxford in December 1940, Franz Simon, now officially working for the
MAUD Committee, produced a report nearly as crucial to the future of
uranium-bomb development as the original Frisch-Peierls memoranda had
been.
1355 It was titled “Estimate of the size of an actual separation plant.” Its
aim, Simon wrote, was “to provide data for the size and costs of a plant
which separates 1 kg per day of 235U from the natural product.
”1356 He
estimated such a plant would cost about £5,000,000 and outlined its
necessities in careful detail.
Simon had never trusted the mails.
He trusted them even less at the height
of the Blitz.
He duplicated some forty copies of his report, accumulated
enough rationed gasoline for a round trip and shortly before Christmas
drove from Oxford into bomb-threatened London to deliver the fruit of half
a year’s hard work, his whole force in the struggle for his country, to G.
P.
omson.
* * *
e Germans may have been collecting radium, as Cockcro thought MAUD
RAY KENT signaled.
ey were certainly laying in industrial stocks of
uranium.
In June 1940, about the time Simon was hammering out his
kitchen strainer, Auer ordered sixty tons of refined uranium oxide from the
Union Miniére in occupied Belgium.1357 Paul Harteck in Hamburg tried
that month to measure neutron multiplication in an ingenious arrangement
of uranium oxide and dry ice—frozen carbon dioxide, a source of carbon
free from any impurity other than oxygen—but was unable to convince
Heisenberg to lend him enough uranium to guarantee unambiguous results.
Heisenberg had larger plans.
He had allied himself with von Weizsácker at
the KWI.
In July they began designing a wooden laboratory building to be
constructed on the grounds of the Kaiser Wilhelm Institute for Biology and
Virus Research, next to the physics institute.
To discourage the curious they
named the building the Virus House.
ey intended to build a subcritical
uranium burner there.
Germany had access to the world’s only heavy-water factory and to
thousands of tons of uranium ore in Belgium and the Belgian Congo.
It had
chemical plants second to none and competent physicists, chemists and
engineers.
It lacked only a cyclotron for measuring nuclear constants.
e
Fall of France—Paris was occupied June 14, an armistice signed June 22—
filled that need.
Kurt Diebner, the War Office’s resident nuclear physics
expert, rushed to Paris.
Perrin, von Halban and Kowarski, he found, had
escaped to England and taken Allier’s twenty-six cans of heavy water with
them, but Joliot had chosen to remain in France.1358 (e French laureate
would become president of the Directing Committee of the National Front,
the largest Resistance organization of the war.)
German officers interrogated Joliot at length when he returned to his
laboratory aer the occupation began.
eir interpreter, sent along from
Heidelberg, turned out to be Wolfgang Gentner, the former Radium
Institute student who had confirmed that Joliot’s Geiger counter was
working properly when Joliot discovered artificial radioactivity in 1933.
Gentner arranged a secret meeting one evening at a student café and warned
Joliot that the cyclotron he was building might be seized and shipped to
Germany.
Rather than allow that outrage Joliot negotiated a compromise:
the cyclotron would stay but German physicists could use it for purely
scientific experiments; Joliot would be allowed in turn to continue as
laboratory director.
e Virus House was finished in October.
Besides a laboratory the
structure contained a special brick-lined pit, six feet deep, a variant of
Fermi’s water tank for neutron-multiplication studies.
By December
Heisenberg and von Weizsäcker had prepared the first of several such
experiments.
With water in the pit to serve as both reflector and radiation
shield they lowered down a large aluminum canister packed with alternating
layers of uranium oxide and paraffin.
A radium-beryllium source in the
center of the canister supplied neutrons, but the German physicists were
able to measure no neutron multiplication at all.
e experiment confirmed
what Fermi and Szilard had already demonstrated: that ordinary hydrogen,
whether in the form of water or paraffin, would not work with natural
uranium to sustain a chain reaction.
at understanding le the German project with two possible moderator
materials: graphite and heavy water.1359 In January a misleading
measurement reduced that number to one.
At Heidelberg Walther Bothe, an
exceptional experimentalist who would eventually share a Nobel Prize with
Max Born, measured the absorption cross section of carbon using a 3.6 -foot
sphere of high-quality graphite submerged in a tank of water.
He found a
cross section of 6.4 × 10−27 cm2, more than twice Fermi’s value, and
concluded that graphite, like ordinary water, would absorb too many
neutrons to sustain a chain reaction in natural uranium.
Von Halban and
Kowarski, now at Cambridge and in contact with the MAUD Committee,
similarly overestimated the carbon cross section—the graphite in both
experiments was probably contaminated with neutron-absorbing impurities
such as boron—but their work was eventually checked against Fermi’s.
Bothe could make no such check.
e previous fall Szilard had assaulted
Fermi with another secrecy appeal:
When [Fermi] finished his [carbon absorption] measurement the
question of secrecy again came up.
I went to his office and said that now
that we had this value perhaps the value ought not to be made public.
And
this time Fermi really lost his temper; he really thought this was absurd.
ere was nothing much more I could say, but next time when I dropped
in his office he told me that Pegram had come to see him, and Pegram
thought that this value should not be published.
From that point the
secrecy was on.
1360
It was on just in time to prevent German researchers from pursuing a
cheap, effective moderator.
Bothe’s measurement ended German
experiments on graphite.
Nothing in the record indicates the overestimate
was deliberate, but it is worth noting that Walther Bothe, a protege of Max
Planck, had been hounded from the directorship of the physics institute of
the University of Heidelberg in 1933 because he was anti-Nazi.
“ese
galling fights so affected my health,” he wrote later in a brief unpublished
memoir, “that I had to spend a long period in a Badenweiler sanitorium.”
When Bothe was well again Planck appointed him to the Kaiser Wilhelm
Society’s Heidelberg physics institute, but “the Nazis continued to harass me,
even to the accusation of scientific fraud.
”1361
At nearly the same time—early 1941—Harteck learned at Hamburg what
Otto Frisch had recently learned at Liverpool.
Frisch had moved to the
industrial port city in the northwest of England to work with Chadwick and
Chadwick’s cyclotron.
He built a Clusius tube there with a student assistant
Chadwick assigned him—they moved in such energetic coordination
through the laboratory that they won the nickname “Frisch and Chips”—
and discovered, says Frisch, that “uranium hexafluoride is one of the gases
for which the Clusius method does not work.” 1362 e discovery set the
British program back not at all, since Simon was already hard at work on
gaseous barrier diffusion.
But the German researchers had placed such faith
in thermal diffusion that they had not bothered to develop alternatives.
ey
quickly began doing so and identified several promising methods; oddly
enough, barrier diffusion was not among them.
Restudying the separation
problem made it even clearer that U235 and U238 could only be separated
by brute-force methods and at great expense.
When Harteck reported to the War Office in March 1941, following a
conference with his colleagues, he stressed their consensus that isotope
separation would be feasible “only for special applications in which
cheapness is but a secondary consideration.
”1363 Only for a bomb, he meant
—so he told the historian David Irving aer the war.
e German physicists
gave “special applications” second place on their list; they recommended
urgent work first of all on the production of heavy water.
Like Fermi and
Szilard, they opted initially for a slow-neutron chain reaction in natural
uranium.
Make that reaction work and “special applications” might follow.
Knowing no more than they knew, they hardly had a choice.
* * *
Lieutenant Colonel Suzuki reported back to Lieutenant General Yasuda in
October 1940.1364 He confined his report to a basic issue: the availability to
Japan of uranium deposits.
He looked beyond Japan to Korea and Burma
and concluded that his country had access to sufficient uranium.
A bomb
was therefore possible.
Yasuda turned then to the director of Japan’s Physical and Chemical
Research Institute, who passed the problem on to his country’s leading
physicist, Yoshio Nishina.
Nishina, born late in the Meiji era and fiy years
old in 1940, known for theoretical work on the Compton Effect, had studied
with Niels Bohr in Copenhagen, where he was remembered as a
cosmopolitan and exceptional man.
He had built a small cyclotron at his
Tokyo laboratory, the Riken, and with help from an assistant who had
trained at Berkeley was building in 1940 a 60-inch successor with a 250-ton
magnet, the plans for which had been donated by Ernest Lawrence.
More
than one hundred young Japanese scientists, the cream of the crop, worked
under Nishina at the Riken; to them he was Oyabun, “the old man,” and he
ran his laboratory Western-style with warmth and informality.
e Riken began measuring cross sections in December.
In April 1941 the
official order came through: the Imperial Army Air Force authorized
research toward the development of an atomic bomb.
* * *
Leo Szilard was known by now throughout the American physics
community as the leading apostle of secrecy in fission matters.
To his
mailbox, late in May 1940, came a puzzled note from a Princeton physicist,
Louis A.
Turner.
Turner had written a Letter to the Editor of the Physical
Review, a copy of which he enclosed.1365 It was entitled “Atomic energy from
U238” and he wondered if it should be withheld from publication.
“It seems
as if it was wild enough speculation so that it could do no possible harm,”
Turner told Szilard, “but that is for someone else to say.
”1366
Turner had published a masterly twenty-nine-page review article on
nuclear fission in the January Reviews of Modern Physics citing nearly one
hundred papers that had appeared since Hahn and Strassmann reported
their discovery twelve months earlier; the number of papers indicates the
impact of the discovery on physics and the rush of physicists to explore
it.1367 Turner had also noted the recent Nier/Columbia report confirming
the attribution of slow-neutron fission to U235.
(He could hardly have
missed it; the New York Times and other newspapers publicized the story
widely.
He wrote Szilard irritably or ingenuously that he found it “a little
difficult to figure out the guiding principle [of keeping fission research
secret] in view of the recent ample publicity given to the separation of
isotopes.” 1368) His reading for the review article and the new Columbia
measurements had stimulated him to further thought; the result was his
Physical Review letter.
Since U235 is responsible for slow-neutron fission, the letter pointed out,
and ordinary uranium contains only one part in 140 of that isotope, “it is
natural to conclude that only 1/140 of any quantity of U can be considered
as a possible source of atomic energy if slow neutrons are to be used.” 1369
But the truth may be otherwise, Turner went on.
e fission energy of most
of the U238, if it could not be used directly, might yet find indirect release.
Turner was referring to the possibility that bombarding uranium with
neutrons converted some of the uranium to transuranic elements, the
transuranics that Bohr had hoped might have been banished by the
discovery of fission.
When an atom of U238 captured a neutron it became
the isotope U239.
at substance itself might fission, Turner suggested.
But
whether or not U239 did so, it was energetically unstable and would
probably decay by beta emission to new elements heavier than uranium.
And one or more of those new elements might be fissionable by slow
neutrons—which would thereby indirectly put U238 to work.
e next element up the periodic table from uranium would be element
93.
Turner selected as the likeliest candidate for fission not 93 X 239, however,
but the element next along, the element that 93 would probably decay to, 94
X 239, which he called “eka-osmium.” 1 And 94 EkaOs 239, Turner proposed,
changing from an odd to an even number of neutrons when it absorbed a
neutron preparatory to fissioning (239 nucleons—94 protons = 145 neutrons
+ 1 = 146) just as U235 changed to U236, ought to be even more fissionable
than the lighter uranium isotope: “In 94EkaOs240...
the excess energy would
be even larger than in 92 U 236 and a large cross section for fission would be
expected.
”1370, 1371
While Turner was thinking these theories through, two Berkeley men,
Edwin M.
McMillan and Philip M.
Abelson, were moving independently
toward demonstrating them.
McMillan, a slim, freckled, California-born
experimentalist, had been one of the men most responsible in the 1930s for
improving Ernest Lawrence’s cyclotrons to the point where they worked
steadily and produced reliable results.
Soon aer the news of the discovery
of fission reached Berkeley in late January 1939 he had devised an elegantly
simple experiment to explore the phenomenon.
“When a nucleus of
uranium absorbs a neutron and fission takes place,” McMillan told an
audience later, “the two resulting fragments fly apart with great violence,
sufficient to propel them through the air, or other matter, for some distance.
is distance, called the ‘range,’ is a quantity of some interest, and I
undertook to measure it.” He did so first with thin sheets of aluminum foil
“like the pages of a book” stacked on a layer of uranium oxide backed with
filter paper.
1372 He bombarded the uranium with slow neutrons.
Some of the
fission fragments recoiled up into the stack of foils; each fragment
embedded itself in a single sheet of foil at the end of its range, which
depended on its mass; McMillan could then simply check successive sheets
of foil in an ionization chamber, look for the characteristic half-lives of
various fission products and read out the range (the uranium nucleus splits
in many different ways, producing many different lighter-element nuclei).
But aluminum itself is activated by neutron bombardment, which made
half-life measurements difficult.
So McMillan replaced the foils with a stack
of cigarette papers previously treated with acid to remove any trace of
minerals that might develop radioactivity under bombardment.
“Nothing
very interesting about the fission fragments came out of this,” he comments.
e uranium coating on the filter paper under the stack of cigarette papers,
on the other hand, “showed something very interesting.
”1373 It showed two
half-life activities different from those of the fission products that had
recoiled away.
And since whatever had remained in the uranium layer had
not recoiled, the two different activities were probably not fission products.
ey were probably radioactivities induced in the uranium by captured
neutrons.
McMillan suspected that one of the two activities, the one with a
half-life of 23 minutes, was one that Hahn, Meitner and Strassmann had
identified in the 1930s as U239, “a uranium isotope produced by resonance
neutron capture.
”1374 e other activity le behind in the uranium layer had
a longer half-life, about 2 days.
In his report on his foil and cigarette-paper
experiments McMillan chose not to speculate on what that second activity
might be, but privately, he remembers, he thought “the two-day period
could...
be the product of the beta-decay of U-239, and therefore an
isotope of [transuranic] element 93; in fact, this was the most reasonable
explanation.” 1375
To check that explanation McMillan needed some hint of the substance’s
chemical identity.
He expected that element 93 would behave chemically like
the metal rhenium, element 75, next to osmium on the periodic table—
would be “eka-rhenium” in the old terminology.
He bombarded a larger
uranium sample and enlisted the aid of Emilio Segré, who was now working
as a research associate at Berkeley.
“Segré was very familiar with the
chemistry of [rhenium], since he and his co-workers [studying rhenium]
had discovered [a similar element], now called technetium, in 1937.” Segrè
began a chemical analysis of the irradiated uranium; in the meantime
McMillan sharpened his half-life measurement to 2.3 days.
Segrè, says
McMillan, “showed that the 2.3 -day material had none of the properties of
rhenium, and indeed acted like a rare earth instead.” e rare earths,
elements 57 (lanthanum) to 71 (lutetium), form a chemically closely related
and odd series between barium and hafnium.
Because of their middle-table
atomic weights near barium, they oen turn up as fission products.
When
Segrè found the 2.3 -day activity acting not like rhenium, as expected, but
like a rare earth, McMillan assumed that was what it was: “Since rare earths
are prominent among the fission products, this discovery seemed at the time
to end the story.” Segrè even published a paper on his work titled “An
unsuccessful search for transuranic elements.” 1376
McMillan might have le it there, but the fact that the 2.3 -day substance
did not recoil away from the uranium layer nagged at him.
“As time went on
and the fission process became better understood, I found it increasingly
difficult to believe that one fission product should behave in a way so
different from the rest, and early in 1940 I returned to the problem.
”1377 e
60-inch cyclotron, with a massive rectangular-framed magnet spacious
enough to shelter Lawrence’s entire crew between its poles for a photograph
—twenty-seven men, two rows seated on the lower jaw of the beast,
Lawrence prominent at center, and a third row standing inside its maw—was
up and running by then; McMillan used it to study the 2.3 -day activity in
more detail.
He studied the activity chemically as well and managed the
significant observation that it did not always fractionally crystallize out of
solution as a rare earth would.
“By now it was the spring of 1940,” McMillan continues, “and Dr.
Philip
Abelson came to Berkeley for a short vacation.” Abelson was the young
experimentalist for whose benefit Luis Alvarez had vacated his Berkeley
barber chair half-shorn to pass along the news of the discovery of fission.
He
had finished his Berkeley Ph.D.
and signed on with Merle Tuve at the DTM.
Like McMillan, he had become suspicious of the conclusion that the 2.3 -day
activity was merely another rare-earth fission product.
He found time in
April 1940 to begin sorting out its chemistry—although he was a physicist
by graduate training, he had earned his B.S.
in chemistry at Washington
State.
But he needed a bigger sample of bombarded uranium than he could
produce with DTM equipment.
“When he arrived for his vacation,” says
McMillan, “and our mutual interest became known to one another, we
decided to work together.
”1378 McMillan made up a new batch of irradiated
uranium.
Abelson pursued its chemistry.
“Within a day,” Abelson recalls, “I established that the 2.3 -day activity had
chemical properties different from those of any known element....
[It]
behaved much like uranium.
”1379 Apparently the transuranics were not
metals like rhenium and osmium but were part of a new series of rareearth-
like elements similar to uranium.
For a rigorous proof that they had found a
transuranic the two men isolated a pure uranium sample with strong 23-
minute U239 activity and demonstrated with half-life measurements that
the 2.3 -day activity increased in intensity as the 23-minute activity declined.
If the 2.3 -day activity was different chemically from any other element and
was created in the decay of U239, then it must be element 93.
McMillan and
Abelson wrote up their results.
McMillan had already thought of a name for
the new element—neptunium, for the next planet out beyond Uranus—but
they chose not to offer the name in their report.
ey mailed the report,
“Radioactive element 93,” to the Physical Review on May 27, 1940, the same
day Louis Turner sent Szilard his transuranic theories: anticipation and
discovery can cut that close in science.
1380
Presumably Szilard did not yet know of the Berkeley work (published June
15) when he answered Turner’s letter on May 30, since he makes no mention
of it, but he recognized the logic of Turner’s argument, told him “it might
eventually turn out to be a very important contribution”—and proposed he
keep it secret.
1381 Szilard saw beyond what Turner had seen.
He saw that a
fissile element bred in uranium could be chemically separated away: that the
relatively easy and relatively inexpensive process of chemical separation
could replace the horrendously difficult and expensive process of physical
separation of isotopes as a way to a bomb.
But unstable element 93,
neptunium, was not yet that fissile element and Szilard did not yet realize
how small a quantity of pure fissile material was needed to make a critical
mass.
(Turner was first with his observation, but he was not alone.
e idea
occurred independently to von Weizsácker one day in July, before the June
Physical Review reached him in Germany with the McMillan-Abelson news,
while he was riding the Berlin subway, though he assumed element 93
would do the job; he offered the idea to the War Office in a five-page
report.
1382 A British team at the Cavendish worked it out and presented it to
the MAUD Committee early in 1941.
But the Germans thought only heavy
water could make a uranium burner go in which the new elements might
breed, and the British had become optimistic about isotope separation.
Neither group therefore pursued the Turner approach.)
Aer Abelson returned to Washington, McMillan pressed on.
Unstable
neptunium decayed by beta emission with a 2.3 -day half-life; he suspected it
decayed to element 94.
By analogy with uranium, which emits alpha
particles naturally, element 94 should also be a natural alpha emitter.
McMillan therefore looked for alphas with ranges different from the
uranium alphas coming off his mixed uranium-neptunium samples.
By
autumn he had identified them.
He tried some chemical separations,
“finding that the alpha-activity did not belong to an isotope of protactinium,
uranium or neptunium.” 1383 He was that close.
But American science, spurred on by British appeals, was finally gearing
up for war.
Churchill had sent over Henry Tizard in the late summer of 1940
with a delegation of experts and a black-enameled metal steamer trunk, the
original black box, full of military secrets.
e prize specimen among them
was the cavity magnetron developed in Mark Oliphant’s laboratory at
Birmingham.
John Cockcro, a future Nobel laureate with a vital mission,
traveled along to explain the high-powered microwave generator.
e
Americans had never seen anything like it before.
Cockcro got together
one weekend in October with Ernest Lawrence and multimillionaire
physicist-financier Alfred Loomis, the last of the gentlemen scientists, at
Loomis’ private laboratory in the elegant suburban New York colony of
Tuxedo Park.
at meeting laid the groundwork for a major new NDRC
laboratory at MIT.
To keep its work secret it was named the Radiation
Laboratory, as if serious scientists might actually be pursuing applications so
dubious as those bruited by visionaries from nuclear physics.
Loomis
wanted Lawrence to direct the new laboratory.
Lawrence preferred to stay at
Berkeley laying plans and raising funds for a new 184-inch cyclotron but
was willing to encourage his best people to move to Cambridge.
He
convinced McMillan: “I le Berkeley in November 1940 to take part in the
development of radar for national defense.” 1384 Lawrence’s and McMillan’s
priorities are a measure of the priorities of American science in late 1940.
Peacetime cyclotrons and radar for air defense came first before
superbombs.
With a different perspective on the matter, James Chadwick at
Liverpool was so uncharacteristically incensed by the publication of the
McMillan-Abelson paper reporting element 93 that he asked for, and got, an
official protest through the British Embassy.
An attache was duly dispatched
to Berkeley to scold Ernest Lawrence, the 1939 Nobel laureate in physics, for
giving away secrets to the Germans in perilous times.
Laura and Enrico Fermi and their two children had moved from a
Manhattan apartment in the summer of 1939 across the George Washington
Bridge and beyond the Palisades to the pleasant suburb of Leonia, New
Jersey.
Harold Urey, a short, intense, enthusiastic man, was a resident along
with other Columbia families and had convinced the Fermis to buy a house
there, praising Leonia’s “excellent public schools,” Laura writes, and extolling
“the advantages of living in a middle-class town where one’s children may
have all that other children have.” 1385 Among much good advice Urey
cautioned the Italian couple to wage eternal war on crabgrass.
Fermi was a
product of Roman apartments; he quickly identified Digitaria sanguinalis
neutrally as “an unlicensed annual” and chose to ignore it.1386 Laura
prepared to do battle but was unable to distinguish crabgrass from sod.
Urey
dropped by one day to give her counsel and identified the problem.
“D’you
know what’s wrong with your lawn, Laura?” the chemistry laureate asked
her compassionately.1387 “It’s all crab grass.” Life was pleasant in Leonia; Fermi practiced fitting in.
Segré remembers that his friend “purposely
studied contemporary Americana and read the comic strips....1388 Among
adult immigrants, I have never seen a comparably earnest effort toward
Americanization.”
Segrè traveled to Indiana toward the end of 1940 to interview at Purdue,
perfunctory interviewing because he meant to stay at Berkeley—“the
machine was so good, I could do these things that nowhere else could I
do.” 1389, 1390 He continued eastward to visit the Fermis in Leonia.
Independently of Turner, Segré recalls, both he and Fermi had been thinking
about element 94.
On December 15, he writes, “we had a long walk along
the Hudson, in freezing weather, during which we spoke of the possibility
that the isotope of mass 239 of element 94...
might be a slow neutron
fissioner.
If this proved to be true, [it] could substitute for 235U as a nuclear
explosive.
Furthermore, a nuclear reactor fueled with ordinary uranium
would produce [the new element].
is gave an entirely new perspective on
the making of nuclear explosives, eliminating the need to separate uranium
isotopes, at that time a truly scary problem.” 1391
Lawrence happened to be visiting New York.
“Fermi, Lawrence, Pegram
and I met in Dean Pegram’s office at Columbia University and developed
plans for a cyclotron irradiation that could produce a sufficient amount of
[element 94].
”1392 Aer Christmas Segré returned to Berkeley.
A young chemist there, Glenn T.
Seaborg, had already begun working
toward identifying and isolating element 94.
Born in Michigan of Swedish-
American parents, Seaborg had grown up in Los Angeles and taken his
Ph.D.
at Berkeley in chemistry in 1937, when he was twenty-five.
He was
exceptionally tall, thin, guarded in the Swedish way but gied and
comfortable at work.
e published record of Otto Hahn’s 1933 Cornell
lectures, Applied Radiochemistry, had been his guidebook in graduate
school: radiochemistry was his passion.
He had been practicing it at
Berkeley in January 1939 when the news of fission arrived; like Philip
Abelson, he was excited by the discovery and chagrined to have missed it
and had walked the streets for hours the night he heard.
As early as the end of August he had bombarded a sample of uranium to
produce neptunium and had assigned one of his second-year graduate
students, Arthur C.
Wahl, to study its chemistry.
His other collaborator in
the search for 94 was Joseph W.
Kennedy, like Seaborg a Berkeley chemistry
instructor.
By late November the group had progressed through four more
bombardments, unraveling enough of neptunium’s chemistry to devise
techniques for isolating highly purified samples.
Seaborg then wrote
McMillan at MIT, a letter he summarizes in a careful history he wrote later
that he cast as a contemporary diary: “I suggested that since he has now le
Berkeley...
and is therefore not in a position to continue this work [of
studying neptunium and looking for element 94], that we would be very
glad to carry on in his absence as his collaborators.” 1393 McMillan acceded in
mid-December; by the time Segré returned to Berkeley Seaborg had
separated out significant fractions of material from his bombarded samples,
including uranium, fission products, purified neptunium and a rare-earth
fraction that might contain 94.
Two searches were thus to proceed simultaneously.1394 Seaborg’s team
would follow one especially intense alpha emitter it had identified in the
hope of demonstrating that it was an isotope of 94, chemically different from
all other known elements.
At the same time, Segré and Seaborg would
produce neptunium 239 in quantity, look for its decay product (which ought
to be 94239) and attempt to measure that substance’s fissibility.
Segrè and Seaborg bombarded ten grams of a solid uranium compound,
uranyl nitrate hexahydrate (UNH), for six hours in the 60-inch cyclotron on
January 9.
ey bombarded five more grams for an hour the next morning.
By aernoon they knew from ionization-chamber measurements that they
could make 94 by cyclotron bombardment; one kilogram of UNH, they
calculated, suitably irradiated, should produce about 0.6 microgram (one
millionth of a gram) from neptunium aer allowing time for beta decay.
1395
Seaborg’s team identified an alpha-emitting daughter of Np238 on January
20.
Definitive proof that it was 94 required chemical separation, and that
delicate, tedious work proceeded during February.
e crucial breakthrough
came at the beginning of a week when everyone routinely labored past
midnight to pursue the difficult fractionations to their end.
On Sunday
aernoon, February 23, Wahl discovered he could precipitate the alpha
emitter from acid solution using thorium as a carrier.
But he was not then
able to separate the alpha emitter from the thorium.
He talked to a Berkeley
chemistry professor who suggested using a more powerful oxidizing agent.
at evening Seaborg and Segré began bombarding 1.2 kilograms of UNH
in the 60-inch cyclotron to transmute some of its uranium into neptunium.
ey packed the UNH into glass tubes, set the tubes in holes drilled into a
10-inch block of paraffin and set the paraffin in a wooden box.
en they
arranged the wooden box behind the beryllium target of the big cyclotron,
which battered copious quantities of neutrons from the beryllium with
powerful 16 MeV deuterons—favorite cyclotron projectiles, deuterium
nuclei from heavy water.
With the UNH in place in the cyclotron Seaborg
climbed the stairs to the third floor of Gilman Hall where Wahl brewed
fractionations under the roof in a cramped room relieved by a small balcony.
Wahl tried the new oxidation chemistry that evening with Seaborg at his
side.
It worked; the thorium precipitated from solution and the alpha emitter
stayed behind, enough of it to read out about 300 kicks per minute on the
linear amplifier.
at, writes Seaborg, was the “key step in its discovery,” but
they still needed a precipitate of the alpha emitter and they pushed on
through the night.
1396 Seaborg remembers noticing the new day—lightning
over San Francisco to the west across the Bay—when he stepped out onto
the balcony to clear his lungs of fumes.
1397 Working again past midnight on
Tuesday, Wahl filtered out a precipitate cleared of thorium.
“With this final
separation from ,” Seaborg records with emphasis, “it has been
demonstrated that our alpha activity can be separated from all known
elements and thus it is now clear that our alpha activity is due to the new
element with the atomic number 94” 1398
e bombardment of Segrè’s and Seaborg’s kilogram sample, interrupted
from time to time by other experiments that commanded the cyclotron,
continued for a week.
e UNH was rendered more intensely radioactive;
the radioactivity would increase dangerously as they concentrated the
Np239 they had made.
ey began working with goggles and lead shielding,
dissolving the uranium first in two liters of ether and then proceeding
through a series of laborious precipitations.
eir fih and sixth reprecipitations they finished on ursday, March 6.
From 1.2 kilograms of UNH they had now separated less than a millionth of
a gram of pure Np239 mixed with sufficient carrier to stain a miniature
platinum dish that measured two-thirds of an inch across and half an inch
deep.
When they had dried this speck of matter God had not welcomed at
the Creation they simply snipped off the sides of the platinum dish, covered
the sample with a protective layer of Duco Cement, glued the dish to a piece
of cardboard labeled Sample A and set it aside until it decayed completely to
94239.
On Friday, March 28 (of the week when Field Marshal Erwin Rommel,
commander of the Afrika Korps, opened a major offensive in North Africa;
when the British meat ration was reduced to six ounces per person per week;
when British torpedo bombers successfully attacked the Italian fleet as it
returned from the Aegean, a performance that greatly interested the
Japanese), Seaborg recorded:
is morning Kennedy, Segrè and I made our first test for the
fissionability of 94239 using Sample A....1399
Kennedy has constructed during the past few weeks a portable
ionization chamber and linear amplifier suitable for detecting fission
pulses....
Sample A (estimated to contain 0.25 micrograms of 94239) was
placed near the screened window of the ionization chamber embedded in
paraffin near the beryllium target of the 37-inch cyclotron.
e neutrons
produced by the irradiation of the beryllium target with 8 MeV deuterons
give a fission rate of 1 count per minute per microampere.
When the
ionization chamber is surrounded by a cadmium shield, the fission rate
drops to essentially zero....
is gives strong indications that 94239 undergoes fission with slow
neutrons.
Not until 1942 would they officially propose a name for the new element
that fissioned like U235 but could be chemically separated from uranium.
But Seaborg already knew what he would call it.
Consistent with Martin
Klaproth’s inspiration in 1789 to link his discovery of a new element with the
recent discovery of the planet Uranus and with McMillan’s suggestion to
extend the scheme to Neptune, Seaborg would name element 94 for Pluto,
the ninth planet outward from the sun, discovered in 1930 and named for
the Greek god of the underworld, a god of the earth’s fertility but also the
god of the dead: plutonium.
* * *
Frisch and Peierls had calculated a small U235 critical mass on the basis of
sensible theory.1400 rough the winter Merle Tuve’s group at the DTM had
continued to refine its cross-section measurements; in March Tuve was able
to send to England a measured U235 fast-fission cross section that the
British used to confirm a critical mass somewhat larger than the Frisch-
Peierls estimate: about eighteen pounds untamped, nine or ten pounds
surrounded by a suitably massive and reflective tamper.
“is first test of
theory,” Peierls wrote triumphantly that month, “has given a completely
positive answer and there is no doubt that the whole scheme is feasible
(provided the technical problems of isotope separation are satisfactorily
solved) and that the critical size for a U sphere is manageable.
”1401
Chadwick had also made further cross-section measurements.
He was
already a sober man; when he saw the new numbers a more intense sobriety
seized him.
He described the change in 1969 in an interview:
I remember the spring of 1941 to this day.
I realized then that a nuclear
bomb was not only possible—it was inevitable.
Sooner or later these ideas
could not be peculiar to us.
Everybody would think about them before
long, and some country would put them into action.
And I had nobody to
talk to.
You see, the chief people in the laboratory were Frisch and [Polish
experimental physicist Joseph] Rotblat.
However high my opinion of
them was, they were not citizens of this country, and the others were quite
young boys.
And there was nobody to talk to about it.
I had many
sleepless nights.
But I did realize how very very serious it could be.
And I
had then to start taking sleeping pills.
It was the only remedy.
I’ve never
stopped since then.
It’s 28 years, and I don’t think I’ve missed a single
night in all those 28 years.1402
12
A Communication from Britain
James Bryant Conant traveled to London in the winter of 1941 to open a
liaison office between the British government and the National Defense
Research Council.
1403 Conant was the first American scientist of
administrative rank to visit the beleaguered nation following the ad hoc
exchanges of the Tizard Mission and he came to count the trip “the most
extraordinary experience of my life.” “I was hailed as a messenger of hope,”
he writes in his autobiography.
“I saw a stouthearted population under
bombardment.
I saw an unflinching government with its back against the
wall.
Almost every hour I saw or heard something that made me proud to be
a member of the human race.” 1404
e Harvard president, who would be forty-seven late in March, was
welcomed not only because of his university affiliation or his distinction as a
member of the NDRC.
He had been an outspoken opponent of American
isolationism during the long months of the phony war and was therefore
welcomed especially as a sign—with only the Prime Minister dissenting.
Churchill was less than delighted at the prospect of lunching with the
president of Harvard.
“What shall I talk to him about?” he was heard to ask.
“He thought you would be an old man with a white beard, exuding learning
and academic formality,” Brendon Bracken, Churchill’s aide, told Conant
aerward.
1405 But braced by the American’s belligerently pro-British views
and put at ease by the tweed suit he chose to wear, the Prime Minister
eventually warmed over lunch in the bomb-shelter basement at 10 Downing
Street, proffering a Churchillian monologue during which he repeated one
of his choicer recent coinages: “Give us the tools, and we will finish the job.”
In 1920, at twenty-seven, when Conant was courting the woman he would
marry—she was the only child of the Nobel laureate Harvard chemist T.
W.
Richards, a pioneer in measuring atomic weights—he had shared hopes for a
grand future with her that coming from a less able man might have sounded
absurd.
“I said that I had three ambitions.
e first was to become the
leading organic chemist in the United States; aer that I would like to be
president of Harvard; and aer that, a Cabinet member, perhaps Secretary of
the Interior.” 1406 ose may not seem conjoint ambitions, but Conant
managed a version of each in turn.
He was born of a Massachusetts family
that had resided in the state since 1623.
Aer Roxbury Latin and Harvard
College he had taken a double Ph.D.
under his future father-in-law in
organic and physical chemistry.
He emerged from the Great War with the
rank of major for his work in poison-gas research at Edgewood.
In his
autobiography, written late in life, he justified his participation:
I did not see in 1917, and do not see in 1968, why tearing a man’s guts out
by a high-explosive shell is to be preferred to maiming him by attacking
his lungs or skin.
All war is immoral.
Logically, the 100 percent pacifist
has the only impregnable position.
Once that is abandoned, as it is when a
nation becomes a belligerent, one can talk sensibly only in terms of the
violation of agreements about the way war is conducted, or the
consequences of a certain tactic or weapon.1407
Like Vannevar Bush, Conant was a patriot who believed in the application of
advanced technology to war.
“Conant achieved an international reputation in both natural products
chemistry and in physical-organic chemistry,” writes the Ukrainian-born
Harvard chemist George B.
Kistiakowsky.
1408 Natural products include
chlorophyll and hemoglobin and Conant contributed to the unraveling of
both those vital molecules.
His studies also helped generalize the concept of
acids and bases, a concept now considered fundamental.
If not the leading
American organic chemist of his day, he ranked among the leaders.
When
Caltech tried to lure him away with a large research budget Harvard topped
the offer and refused to let him go.
Number two on Conant’s youthful list, the presidency of his alma mater,
he won in 1933.
He told the members of the Harvard Corporation who
approached him that he didn’t want the job, which was apparently a
prerequisite, but would serve if elected.
He was forty at the time of his
election.
He created the modern Harvard of eminent scholarship and
publish-or-perish, up-or-out.
Conant’s third ambition achieved approximate fulfillment aer the war in
high, though less than cabinet-rank, appointment; his long span of
voluntary government service began with the NDRC.
In England in the late winter of 1941 he met with the leaders of the British
government, had an audience with the King, picked up an honorary degree
at Cambridge and walked the Backs aerward to see the crocuses in bloom,
made room for the NDRC mission among hostile U.S.
military and naval
attaches, lunched with Churchill again.
His mission in Britain was
diplomatic rather than technical.
He discussed gas warfare and explosives
manufacture but was unable to share in the intense exchange of information
on radar because he knew very little about electronics.
But although he was
familiar with the work on uranium and it fell within his official NDRC
responsibilities, secrecy and his “strong belief in the ‘need to know’
principle” kept Conant from learning what the British had learned about the
possibility of a bomb.1409
He met a “French scientist” at Oxford, probably Hans von Halban, who
complained of inaction on uranium-heavy water research.
“Since his
complaints were clearly ‘out of channels,’ I quickly terminated the
conversation and forgot the incident.” at reaction was understandable:
Conant could hardly know what security arrangements the British might
have made with the Free French.
But he also shied from Lindemann.
ey
were lunching alone at a London club.
“He introduced the subject of the
study of the fission of uranium atoms.
I reacted by repeating the doubts I
had expressed and heard expressed at NDRC meetings.” Lindemann
brushed them aside and pounced:
“You have le out of consideration,” said [Lindemann], “the possibility of
the construction of a bomb of enormous power.” “How would that be
possible?” I asked.
“By first separating uranium 235,” he said, “and then
arranging for the two portions of the element to be brought together
suddenly so that the resulting mass would spontaneously undergo a self-
sustaining reaction.”
Remarkably, the chairman of the chemistry and explosives division of the
NDRC adds that, as late as March 1941, “this was the first I had heard about
even the remote possibility of a bomb.” Nor did he pursue the matter.
“I
assumed, quite correctly, that if and when Bush wished to be in touch with
the atomic energy work in England, he would do so through channels
involving Briggs.” No wonder the Hungarian conspirers continued to tear
their hair.
* * *
en for the first time a ranking American physicist joined the debate whose
voice could not be ignored.
Even before Seaborg and Segré confirmed the
fissibility of plutonium, Ernest Lawrence had measured the prevailing
American skepticism and conservatism against the increasing enthusiasm of
his British friends and responded with characteristic fervor.
Ralph H.
Fowler, Ernest Rutherford’s widower son-in-law, had visited Berkeley during
the 1930s and attended picnics and weekend parties with the inventor of the
cyclotron.
Fowler was British scientific liaison officer in Washington now
and from that close vantage he urged Lawrence to get involved.
So did Mark
Oliphant, whom Lawrence had met and liked on a visit to the Cavendish
aer the 1933 Solvay Conference.
Lawrence had encouraged the search for plutonium partly because he saw
little hope for isotope separation by any of the methods so far discussed—by
centrifuge, thermal diffusion or barrier diffusion.
But around the beginning
of the year he began thinking about separating isotopes electromagnetically,
by the process that had already worked on a microscopic scale for Alfred
Nier.
It occurred to Lawrence that he could modify his superseded 37-inch
cyclotron into a big mass spectrometer.
e fact that Nier thought
electromagnetic separation on an industrial scale impossible only spurred
the Berkeley laureate on.
Lawrence lived from machine to machine, as it
were; conceiving a machine to do the job of liberating U235 from its
confinement within U238 (while Fermi’s uranium-graphite reactor
manufactured Berkeley-born plutonium) gave him something solid to fight
for, a tangible program to push.
It assembled itself by stages.
He was not yet ready emotionally to set aside
his peacetime plans.
Warren Weaver, the director of the division of natural
sciences at the Rockefeller Foundation, visited Berkeley in February to see
how construction was progressing on the 4,900-ton, 184-inch cyclotron for
which the foundation had awarded a $1,150,000 grant less than twelve
months earlier.
Lawrence took time to complain about the Uranium
Committee’s sloth—Weaver worked with another division of the NDRC—
but then drove up behind the university to the cyclotron site on the hillside
and first irritated and then enthralled the Rockefeller administrator with
visions of a superior and much larger machine.
Lawrence rehearsed his complaint again in March when Conant, back
from London, traveled out to deliver an address.
“Light a fire under the
Briggs committee,” the energetic Californian badgered the president of
Harvard.
“What if German scientists succeed in making a nuclear bomb
before we even investigate possibilities?” at prepared Lawrence for a full
assault.
1410 He launched it on March 17 when he met with Karl Compton
and Alfred Loomis at MIT.
1411
Loomis had turned to physics aer a lucrative career in the law and
investment banking.
Compton was a physicist of distinction who had taught
for fieen years at Princeton, where he took his Ph.D., before becoming
president of MIT in 1930.
Both men understood the politics of
organizations.
Yet they were sufficiently seized with Lawrence’s fervor that
Compton telephoned Vannevar Bush almost as soon as Lawrence le the
room and dictated a follow-up letter the same day.
Briggs was “by nature
slow, conservative, methodical and accustomed to operate at peacetime
government bureau tempo,” Compton wrote, conveying Lawrence’s blunt
complaints, and had been “following a policy consistent with these qualities
and still further inhibited by the requirement of secrecy.” e British were
ahead even though America had “the most in number and the best in
quality of the nuclear physicists of the world.” e Germans were “very
active.” Briggs had invited only a very few U.S.
nuclear physicists into the
work.
ere were other possibilities in fission research besides the pursuit of
a slow-neutron chain reaction for power, possibilities “capable, if successful,
of far more important military usage.” 1412
ough they felt free thus to lecture Bush, both Loomis and Compton
stood in awe of Lawrence—Loomis had recently contributed $30,000 to a
private fund simply to make it easier for Lawrence to travel around the
country—and thought Bush could do no better than to turn him loose: “I
hasten to say that the idea of Ernest himself taking an active part in any
reorganization was in no sense suggested by him or even in his mind, but I
do believe that it would be an ideal solution.”
Bush’s ego was commensurate with his responsibilities, as Loomis and
Compton ought to have known.
It might have been politic to welcome
Lawrence’s campaign, especially since Loomis was a first cousin and close
friend of Henry L.
Stimson, the respected and influential Secretary of War;
but Bush decided instead to take it as a challenge to his authority, the first
the physics community had mounted since he invented the NDRC,
welcoming a fight he knew he could win.
He met Lawrence in New York two
days aer the MIT meeting and let fly:
I told him flatly that I was running the show, that we had established a
procedure for handling it, that he could either conform to that as a
member of the NDRC and put in his kicks through the internal
mechanism, or he could be utterly on the outside and act as an individual
in any way that he saw fit.
He got into line and I arranged for him to have
with Briggs a series of excellent conferences.
However, I made it very clear
to Lawrence that I proposed to make available to Briggs the best advice
and consultation possible, but that in the last analysis I proposed to back
up Briggs and his committee in their decision unless there was some
decidedly strong case for entering into it personally.
I think this matter
was thoroughly straightened out, therefore, but it le its trail behind.
1413
By threatening to push Ernest Lawrence out into the cold with the emigrès
Bush managed temporarily to confine the uranium problem.
Confinement
lasted less than a month.
In 1940 Lawrence had recruited a Harvard experimentalist named
Kenneth Bainbridge, by trade a nuclear physicist—Bainbridge built the
Harvard cyclotron—to work on radar at MIT.
When Conant went to
London to open the new NDRC office there, Bainbridge and others had
followed, to work with the British each in his own field of competence.
But
since Bainbridge knew nuclear physics as well as radar and had even looked
into isotope separation, the British allowed him also to attend a full-dress
meeting of the MAUD Committee.
To Bainbridge’s surprise, the committee
had “a very good idea of the critical mass and [bomb] assembly
[mechanism], and urged the exchange of personnel....
eir estimate was
that a minimum of three years would be required to solve all the problems
involved in producing an atomic weapon.
”1414 Bainbridge immediately
contacted Briggs and suggested he send someone over to represent the
United States in uranium matters.
1415
Beneath Bush’s organizational bristle lay genuine perplexity.
“I am no
atomic scientist,” he writes candidly; “most of this was over my head.
”1416 As
he saw the situation that April, “it would be possible to spend a very large
amount of money indeed, and yet there is certainly no clear-cut path to
defense results of great importance lying open before us at the present
time.” 1417 But he felt the increasing pressure—Lawrence’s prodding,
Bainbridge’s confirmation of British progress—and reached out now for
help.
“It was Bush’s strategy,” writes the American experimental physicist
Arthur Compton, Karl’s younger brother, “as co-ordinator of the nation’s war
research, to use the National Academy [of Sciences] as the court of final
appeal for important scientific problems.” 1418 On a Tuesday in mid-April,
aer meeting with Briggs, Bush wrote Frank B.
Jewett, the senior Bell
Telephone engineer who was president of the National Academy.
Briggs had
heard from Bainbridge and alerted Bush; Bush and Briggs, “disturbed,” had
conferred.
“e British are apparently doing fully as much as we are, if not
more, and yet it seems as though, if the problem were of really great
importance, we ought to be carrying most of the burden in this country.”
Bush wanted “an energetic but dispassionate review of the entire situation by
a highly competent group of physicists.
”1419 e men chosen ought to have
“sufficient knowledge to understand and sufficient detachment to cold
bloodedly evaluate.”
At a regular Washington meeting of the National Academy the following
Friday Jewett, Bush and Briggs recruited their review group.
ey put
Lawrence on the committee and the recently retired director of the research
laboratory at General Electric, a physical chemist named William D.
Coolidge.
en they sought out Arthur Compton, a Nobel laureate and
professor of physics at the University of Chicago, and proposed he head the
review.
Compton humbly questioned his “fitness for the task” and jumped at
the chance.1420
Arthur Holly Compton was the son of a Presbyterian minister and
professor of philosophy at the College of Wooster in Wooster, Ohio.
Compton’s Mennonite mother was dedicated to missionary causes and had
been the 1939 American Mother of the Year.
He followed his older brother
Karl into science and surpassed him in achievement but preserved the
family piety as well.
“Arthur Compton and God were daily companions,”
notes Leona Woods, Enrico Fermi’s young protégé at the University of
Chicago.
She judged Compton nevertheless “a fine scientist and a fine
man....
He was remarkably handsome all his life and athletically spare and
strong.
”1421 Fermi had concluded, writes Woods, that “tallness and
handsomeness usually were inversely proportional to intelligence,” but “he
excepted Arthur Compton...
whose intelligence he respected
enormously.” 1422
Compton’s physics was first-rate, as Fermi’s respect implies.
He graduated
from the College of Wooster and took his Ph.D.
at Princeton.
In 1919, the
first year of the program, he was appointed a National Research Council
fellow and used the appointment to study under Rutherford at the
Cavendish.
e difficult work he began there—examining the scattering and
absorption of gamma rays—led directly to the discovery of what came to be
called the Compton effect, for which he won the Nobel Prize.
In 1920, Compton writes, he accepted a professorship at Washington
University in St.
Louis, “a small kind of place,” to get out of the mainstream
of physics so that he could concentrate on his scattering studies, which he
was then extending from gamma rays to X rays.
1423 He scattered X rays with
a graphite block and caught them and measured their wavelengths Moseley-
style with a calcite-crystal X-ray spectrograph.
He found that the X rays
scattered by the graphite came out with wavelengths longer than their
wavelengths going in: as if a shout bounced off a distant wall came back
bizarrely deepened to a lower pitch.
If X rays—light—were only a motion of
waves, then their wavelengths would not have changed; Compton had in fact
demonstrated in 1923 what Einstein had postulated in 1905 in his theory of
the photoelectric effect: that light was wave but also simultaneously particle,
photon.
An X-ray photon had collided elastically with an electron, as billiard
balls collide, had bounced off and thereby given up some of its energy.
e
calcite crystal revealed the energy loss as a longer wavelength of X-ray light.
Arnold Sommerfeld hailed the Compton effect—elastic scattering of a
photon by an electron—as “probably the most important discovery which
could have been made in the current state of physics” because it proved that
photons exist, which hardly anyone in 1923 yet believed, and demonstrated
clearly the dual nature of light as both particle and wave.
1424
e subtle experimenter lost his subtlety when he shied from doing
science to proselytizing for God.
Rigor slipped to Chautauqua logic and he
perpetrated such howlers as the notion that Heisenberg’s uncertainty
principle somehow extends beyond the dimensions of the atom into the
human world and confirms free will.
Bohr heard Compton’s Free Will
lecture when he visited the United States in the early 1930s and scoffed.
“Bohr spoke highly of Compton as a physicist and a man,” a friend of the
Danish laureate remembers, “but he felt that Compton’s philosopohy was
too primitive: ‘Compton would like to say that for God there is no
uncertainty principle.
at is nonsense.
In physics we do not talk about God
but about what we can know.
If we are to speak of God we must do so in an
entirely different manner.’ ” 1425
In 1941 war work had already been kind to Arthur Compton’s brother,
moving Karl to national prominence within the science community and
winning an important secret laboratory for MIT.
Arthur wanted as much or
more.
ere was the problem of pacifism, his mother’s Mennonite creed and
a course much discussed at that time in American vestries, a churchly
counterpart to isolationism:
In 1940, my forty-eighth year, I began to feel strongly my responsibility as
a citizen for taking my proper part in the war that was then about to
engulf my country, as it had already engulfed so much of the world.
I
talked, among others, with my minister in Chicago.
He wondered why I
was not supporting his appeal to the young people of our church to take a
stand as pacifists.
I replied in this manner: “As long as I am convinced, as I
am, that there are values worth more to me than my own life, I cannot in
sincerity argue that it is wrong to run the risk of death or to inflict death if
necessary in the defense of those values.” 1426
Arthur Compton was ready, then, “a short time later,” when Bush and the
National Academy asked him to serve.
e review committee met immediately with some of Briggs’ associates in
Washington.
A week later, May 5, 1941, it met again in Cambridge to hear
from other Uranium Committee members and from Bainbridge.
“ere
followed,” writes Compton, “two weeks spent in discussing the military
possibilities of uranium with others who were actively interested.” 1427
Compton worked quickly to complete a seven-page report and delivered it
to Jewett on May 17.
e report began with the statement that the committee was concerned
with “the matter of possible military aspects of atomic fission” and listed
three of those possibilities: “production of violently radioactive materials...
carried by airplanes to be scattered as bombs over enemy territory,” “a power
source on submarines and other ships” and “violently explosive bombs.”
Radioactive dust would need a year’s preparation aer “the first successful
production of a chain reaction,” which meant “not earlier than 1943.” A
power source would need at least three years aer a chain reaction.
Bombs
required concentrating U235 or possibly making plutonium in a chain
reaction, so “atomic bombs can hardly be anticipated before 1945.”
And that was that: no mention of fast-neutron fission, or critical mass, or
bomb assembly mechanisms.
e bulk of the report discussed “progress
toward securing a chain reaction” and considered uranium-graphite,
uranium-beryllium and uranium-heavy water systems.
e committee
proposed giving Fermi all the money he needed for his intermediate
experiment and beyond.
It also, more originally, discovered and emphasized
the decisive long-range challenge of the new field:
It would seem to us unlikely that the use of nuclear fission can become of
military importance within less than two years....
If, however, the chain
reaction can be produced and controlled, it may rapidly become a
determining factor in warfare.
Looking, therefore, to a struggle which
may continue for a decade or more, it is important that we gain the lead in
this development.
at nation which first produces and controls the
process will have an advantage which will grow as its applications
multiply.
Bush was in the process of reorganizing government science when he
received the NAS report.
e NDRC, empowered equally with the military
laboratories and the National Advisory Committee for Aeronautics, had
served for research but lacked the authority to pursue engineering
development.
Bush proposed a new umbrella agency with wide authority
over all government science in the service of war, the Office of Scientific
Research and Development.
Its director—Bush—would report personally to
Roosevelt.
Bush prepared to move up to the OSRD by calling in Conant to
take over the NDRC.1428 , 1429 “And only aer it was clear that I should
shortly have a new position,” writes Conant, “did Bush begin to take me into
his confidence as he pondered on what to do with the Briggs
Committee.
”1430 Against the background of his British experience Conant
told Bush his reaction to Compton’s report was “almost completely negative.”
Jewett had delivered the report to Bush with a cover letter calling it
“authoritative and impressive,” but privately he cautioned Bush that he had
“a lurking fear” that the report “might be over-enthusiastic in parts and not
so well balanced.” 1431, 1432 Jewett also passed it to several senior colleagues for comment, including the 1923 Nobel laureate in physics, Robert A.
Millikan of Caltech, and sent their comments along to Bush in early June.
Bush responded with exasperation compounded with astonishing confusion
about the developments in Britain:
is uranium business is a headache!
I have looked over Millikan’s
comments, and it is quite clear that he wrote them without realizing the
present situation.
e British have apparently definitely established the
possibility of a chain reaction with 238 [sic], which entirely changes the
complexion of the whole affair.
Millikan bases his comments on the
conviction that only 235 holds promise.
is is natural, since he has not
been brought in touch with recent developments which the British have
told us about in great confidence.1433
He agreed that the work “ought to be handled in a somewhat more vigorous
form,” but he was still profoundly skeptical of its promise:
Even if the physicists get all that they expect, I believe that there is a very
long period of engineering work of the most difficult nature before
anything practical can come out of the matter, unless there is an explosive
involved, which I very much doubt.
e OSRD director was not yet convinced despite new word of
plutonium’s remarkable fissibility.
Segrè and Seaborg had continued working
through the spring of 1941 to determine the man-made element’s various
cross sections.
On Sunday, May 18, having finally prepared a sample thin
enough for accurate measurement, they calculated plutonium’s cross section
for slow-neutron fission at 1.7 times that of U235.
When Lawrence heard the
news on Monday, says Seaborg, he swung into action:
We told Lawrence about our definitive demonstration yesterday of the
slow neutron fissionability of 94239 and he was quite excited.
He
immediately phoned the University of Chicago to give the news to Arthur
H.
Compton....
Compton made an immediate attempt to phone
(unsuccessfully) and then sent a telegram to Vannevar Bush....
In his
telegram Compton indicated that the demonstration...
greatly increases
the importance of the fission problem since the available material [i.e.,
U238 transmuted to plutonium] is thus increased by over 100
times....
1434 He said that Alfred Loomis and Ernest Lawrence
accordingly have requested him to urge anew the vital importance of
pushing the [uranium-graphite] work at Columbia.
* * *
Whenever the U.S.
program bogged down in bureaucratic doubt Hitler and
his war machine rescued it.
at summer’s massive escalation, code-named
Operation Barbarossa, was the opening of the Eastern Front at dawn on the
morning of Sunday, June 22, a surge eastward with 164 divisions, including
Finnish and Rumanian components, toward Blitzkrieg invasion of the USSR.
e Führer’s ambitious intention, declared with emphasis in a secret
directive six months earlier, was “to crush Soviet Russia in a quick campaign
even before the conclusion of the war against England.” 1435 Hitler meant to
push all the way to the Urals before winter and commandeer the Soviet
Union’s industrial and agricultural base; by July Panzers had crossed the
Dnieper and were threatening Kiev.
e effect on Conant of his London experiences and the widening war
was paradoxically to increase his skepticism of the program he had just
accepted assignment to administer:
What worried me about Compton’s first report, I told Bush, was the
assumption that achieving a chain reaction was so important that a large
expenditure of both money and manpower was justified.
To me, the
defense of the free world was in such a dangerous state that only efforts
which were likely to yield results within a matter of months or, at most, a
year or two were worthy of serious consideration.
In that summer of 1941,
with recollections of what I had seen and heard in England fresh in my
mind, I was impatient with the arguments of some of the physicists
associated with the Uranium Committee whom I met from time to time.
ey talked in excited tones about the discovery of a new world in which
power from a uranium reactor would revolutionize our industrialized
society.
ese fancies le me cold.
I suggested that until Nazi Germany
was defeated all our energies should be concentrated on one immediate
objective.
1436
Having experienced the London Blitz, Conant had developed a siege
mentality; Bush, as Conant points out, “was faced with a momentous
decision as to priorities.” Both men wanted a hard, practical assessment.
ey decided Compton’s report needed an injection of common sense in the
form of engineering expertise.
Compton discreetly retired from the line; W.
D.
Coolidge, the General Electric scientist, temporarily took his place.
Conant added an engineer from Bell Laboratories and another from
Westinghouse and early in July the enlarged committee reviewed the first
review.
Briggs was a convincing witness.
By then he had received the April 9
minutes of a MAUD technical subcommittee meeting where Peierls
reported that cross-section measurements confirmed the feasibility of a
fastneutron bomb.
Briggs had also just learned from Lawrence that
plutonium had a cross section for fast fission some ten times that of
U238.
1437 Lawrence even submitted a separate report on element 94 that
emphasized for the first time in U.S.
official deliberations the importance of
fast fission over slow.
But Briggs was still preoccupied with a slow-neutron
chain reaction for power production and so was the second NAS report.
“In
the summer of 1941,” John Dunning’s associate Eugene Booth remembers,
“Briggs visited us in the basement of Pupin at Columbia to see our
experiment for the separation of U235 by [gaseous] diffusion of uranium
hexafluoride.
He was interested, blessed us, but sent us no money.” 1438
e American program was in danger for its life that summer, Compton
thought: “e government’s responsible representatives were...
very close
to dropping fission studies from the war program.” 1439 He believed the
program was saved because of Lawrence’s proposal to use plutonium to
make a bomb.
e fissibility of 94 may have convinced Compton.
It was not
decisive for the government’s responsible representatives.
ey were hard
men and needed hard facts.
ose began to arrive.
“More significant than
the arguments of Compton and Lawrence,” writes Conant, “was the news
that a group of physicists in England had concluded that the construction of
a bomb made out of uranium 235 was entirely feasible.” 1440
e British had been trying all winter and spring to pass the word.
In July
they tried again.
G.
P.
omson had assembled a dra final report for the
MAUD Committee to consider on June 23, the day aer Barbarossa
exploded across the Balkans and eastern Poland.
Charles C.
Lauritsen of
Caltech, a respected senior physicist, was beginning work for the NDRC
developing rockets and happened to be in London conferring with the
British at the time of the MAUD dra.
e committee invited him to attend
its July 2 meeting at Burlington House.
Lauritsen listened carefully, took
notes and aerward talked individually with eight of the twenty-four
physicists now attached to the work.
1441 When he returned to the United
States the following week he immediately reported the MAUD findings to
Bush.
“In essence,” says Conant, “he summarized the ‘dra report.’ ”1442 e
physicists Lauritsen had interviewed had all pushed for a U.S.-built gaseous-
diffusion plant.
e British government would not officially transmit the final MAUD
Report to the United States government until early October, but the
committee approved it on July 15 (and thereupon promptly disbanded) and
by then Bush had been passed a copy of the omson dra, which
embodied the essential findings.
e MAUD Report differed from the two
National Academy studies as a blueprint differs from an architect’s
sketch.
1443 It announced at the outset:
We have now reached the conclusion that it will be possible to make an
effective uranium bomb which, containing some 25 lb of active material,
would be equivalent as regards destructive effect to 1,800 tons of T.N.T.
and would also release large quantities of radioactive substances....
A
plant to produce 2¼ lb (1 kg) per day [of U235] (or 3 bombs per month)
is estimated to cost approximately £5,000,000....
In spite of this very
large expenditure we consider that the destructive effect, both material
and moral, is so great that every effort should be made to produce bombs
of this kind....
e material for the first bomb could be ready by the end
of 1943....
Even if the war should end before the bombs are ready the
effort would not be wasted, except in the unlikely event of complete
disarmament, since no nation would care to risk being caught without a
weapon of such destructive capabilities.
Of conclusions and recommendations the report offered, crisply, three:
( i) e committee considers that the scheme for a uranium bomb is
practicable and likely to lead to decisive results in the war.
( ii) It recommends that this work continue on the highest priority and
on the increasing scale necessary to obtain the weapon in the
shortest possible time.
(iii) at the present collaboration with America should be continued
and extended especially in the region of experimental work.
“With the news from Great Britain unofficially in hand,” Conant
concludes in a secret history of the project he draed in 1943, “...
it
became clear to the Director of OSRD and the Chairman of NDRC that a
major push along the lines outlined was in order.” 1444
ey still did not immediately organize that push.
Nor was Conant, to his
postwar recollection, yet convinced that a uranium bomb would work as
described.
British research and considered judgment had at least proposed a
clear-cut program of military development.
Bush took it to Vice President
Henry Wallace, his White House sounding board, who was the only scientist
in the cabinet, a plant geneticist who had developed several varieties of
hybrid corn.
“During July,” writes Conant, “Bush had a discussion with Vice
President Wallace about the question of spending a large amount of
government money on the uranium program.
”1445 Aer which Bush
apparently decided to wait for official transmittal of the final MAUD Report.
“If each necessary step requires ten months of deliberation,” Leo Szilard
had complained to Alexander Sachs in 1940, “then obviously it will not be
possible to carry out this development efficiently.
”1446 e American
program was moving faster now than that, but not by much.
* * *
While Lawrence and Compton championed plutonium that summer, a big,
rawboned, war-battered Austrian hiding out within the German physics
establishment tried to keep the fissile new element out of sight.
He was an
old friend of Otto Frisch:
Fritz Houtermans and I had met in Berlin, but in London [before the war]
I saw a lot more of that impressive eagle of a man, half Jewish as well as a
Communist who had narrowly escaped the Gestapo.
His father had been
a Dutchman, but he was very proud of his mother’s Jewish origin and
liable to counter anti-semitic remarks by retorting “When your ancestors
were still living in the trees mine were already forging cheques!” He was
full of brilliant ideas.
1447
Houtermans had taken a Ph.D.
in experimental physics at Göttingen but
was strong in theory.
One of his brilliant ideas, developed in the late 1920s at
the University of Berlin with a visiting British astronomer, Robert Atkinson,
concerned the production of energy in stars.
Atkinson was familiar with
recent estimates by his older colleague Arthur Eddington that the sun and
other stars burn at temperatures of 10 million and more degrees and have
life spans of billions of years—a prodigious and unexplained expenditure of
energy.
On a walking tour near Göttingen in the summer of 1927 the two
men had wondered if nuclear transformations of the sort Rutherford was
producing at the Cavendish might account for the enduring stellar fires.
ey quickly worked out a basic theory, as Hans Bethe later described it,
“that at the high temperatures in the interior of a star, the nuclei in the star
could penetrate into other nuclei and cause nuclear reactions, releasing
energy.” 1448 e energy would be released when hot (and therefore fast-
moving) hydrogen nuclei collided with enough force to overcome their
respective electrical barriers and fused together, making helium nuclei and
giving up binding energy in the process.
With George Gamow, Houtermans
and Atkinson later named these events thermonuclear reactions because they
proceeded at such high temperatures.
In 1933 Houtermans emigrated to the Soviet Union, “but fell victim,”
writes Frisch, “to one of Stalin’s purges and spent a couple of years in prison;
his wife with two small children managed to escape and get to the U.S.A.
When Hitler made his temporary pact with Stalin in 1939 it included an
exchange of prisoners, and Houtermans was handed back to the Gestapo.”
Max von Laue, whom Frisch celebrates as “one of the few German scientists
with the prestige and courage to stand up against the Nazis,” managed to free
Houtermans and arranged for him to work with a wealthy German inventor,
Baron Manfred von Ardenne, who had studied physics and who maintained
a private laboratory in Lichterfelde, outside Berlin.
1449, 1450 Von Ardenne was pursuing uranium research independently of Heisenberg and the War
Office; to raise funds for the work he had approached the German Post
Office, which commanded a large and largely unused budget for research.
e Minister of Posts, imagining himself handing Hitler the decisive secret
weapon of the war, had funded the building of a million-volt Van de Graaff
and two cyclotrons, all under construction in 1941.
Until they came on line
Houtermans turned his attention to theory.
By August he had independently worked out all the basic ideas necessary
to a bomb.
He discussed them in a thirty-nine-page report, “On the question
of unleashing chain reactions,” that considered fast-neutron chain reactions,
critical mass, U235, isotope separation and element 94.
Houtermans
emphasized making 94.
“Every neutron which, instead of fissioning
uranium-235, is captured by uranium-238,” he wrote, “creates in this way a
new nucleus, fissionable by thermal neutrons.” 1451 He discussed his ideas
privately with von Weizsäcker and Heisenberg, but he saw to it that the Post
Office kept his report in its safe secure from War Office eyes.
He had learned
to cooperate for survival in the Soviet Union, where the NKVD—the KGB
of its day—had knocked out all his teeth and kept him in solitary
confinement for months.
But in Germany as in the USSR he withheld as
much information as he dared.
His private endorsement of 94, to be
transmuted by chain reaction from natural uranium, probably contributed
to the neglect of isotope separation in Germany.
Aer the summer of 1941
the German bomb program depended entirely on uranium and Vemork
heavy water.
* * *
e British, at least, knew where they were going.
Tizard was skeptical of the
MAUD Report and doubted that a bomb could be produced before the end
of the war.
Lindemann—he was Lord Cherwell now, a baron, courtesy of his
friend the P.M.—did not.
Cherwell had followed the MAUD work carefully.
He respected omson; Simon was an old friend; Peierls had read his grunts
correctly aer all.
He trusted their judgment and set to work to reduce the
lengthy report to a memorandum for Churchill.
Churchill liked his
documents held to half a page.
So important was this one that Cherwell
allowed it to run on for two and a half pages.
He thought research should
continue for six months and then face further review.
He thought an
isotope-separation plant should be erected not in the United States but in
England—despite manpower shortages and the risk of German bombing—
or “at worst” in Canada.
In that conclusion he differed from the MAUD
Committee.1452 “e reasons in favor [of an English location],” he wrote,
“are the better chance of maintaining secrecy...
but above all the fact that
whoever possesses such a plant should be able to dictate terms to the rest of
the world.
However much I may trust my neighbor and depend on him, I
am very much averse to putting myself completely at his mercy.
I would,
therefore, not press the Americans to undertake this work.” His summation
narrowed the odds but decisively raised the stakes:
People who are working on these problems consider the odds are ten to
one on success within two years.
I would not bet more than two to one
against or even money.
But I am quite clear that we must go forward.
It
would be unforgivable if we let the Germans defeat us in war or reverse
the verdict aer they had been defeated.
Churchill received Cherwell’s recommendation on August 27.
ree days
later he minuted his military advisers, alluding ironically to the effects of the
Blitz: “Although personally I am quite content with the existing explosives, I
feel we must not stand in the path of improvement, and I therefore think
that action should be taken in the sense proposed by Lord Cherwell.
”1453
e British chiefs of staff concurred on September 3.
* * *
Mark Oliphant helped goad the American program over the top.
“If
Congress knew the true history of the atomic energy project,” Leo Szilard
said modestly aer the war, “I have no doubt but that it would create a
special medal to be given to meddling foreigners for distinguished services,
and Dr.
Oliphant would be the first to receive one.
”1454 Conant in his 1943
secret history thought the “most important” reason the program changed
direction in the autumn of 1941 was that “the all-out advocates of a head-on
attack on the uranium problem had become more vocal and determined”
and mentioned Oliphant’s influence first of all.
1455
Oliphant flew to the United States in late August—he considered the Pan-
American Clipper through Lisbon too slow and usually traveled by
unheated bomber—to work with his NDRC counterparts on radar.
But he
was also charged with inquiring why the United States was ignoring the
MAUD Committee’s findings.
“e minutes and reports...
had been sent to
Lyman Briggs...
and we were puzzled to receive virtually no comment....
I
called on Briggs in Washington, only to find that this inarticulate and
unimpressive man had put the reports in his safe and had not shown them
to members of his Committee.” Oliphant was “amazed and distressed.” 1456
He met then with the Uranium Committee.
Samuel K.
Allison was a new
committee member, a talented experimentalist, a protégé of Arthur
Compton at the University of Chicago.
Oliphant “came to a meeting,”
Allison recalls, “...
and said ’bomb’ in no uncertain terms.
He told us we
must concentrate every effort on the bomb and said we had no right to work
on power plants or anything but the bomb.
e bomb would cost twenty-
five million dollars, he said, and Britain didn’t have the money or the
manpower, so it was up to us.” Allison was surprised.
Briggs had kept the
committee in the dark.
“I thought we were making a power source for
submarines.” 1457
In desperation Oliphant reached out to the most effective champion he
knew in the United States.
He wired Ernest Lawrence: “I’ll even fly from
Washington to meet at a convenient time in Berkeley.” 1458 At the beginning
of September he did.
Lawrence drove Oliphant up the hill behind the Berkeley campus to the
site of the 184-inch cyclotron where they could talk without being
overheard.
Oliphant rehearsed the MAUD Report, which Lawrence had not
yet seen.
Lawrence in turn proclaimed the possibility of electromagnetic
separation of U235 in converted cyclotrons and the virtues of plutonium.
“How much I still admire the way in which things are done in your
laboratory,” Oliphant would write him aer their meeting.
“I feel quite sure
that in your hands the uranium question will receive proper and complete
consideration.” 1459, 1460 Back in his office Lawrence called Bush and Conant and arranged for Oliphant to see them.
From Oliphant he collected a written
summary of the secret British report.
In Washington Conant took Oliphant to dinner and listened with interest.
Bush met him in New York and gave him a barely courteous twenty minutes.
Neither administrator admitted to knowledge of the MAUD Report.
“Gossip
among nuclear physicists on forbidden subjects,” Conant characterizes
Oliphant’s peregrinations in his secret history.1461
Oliphant also stopped by to talk to Fermi.
He found the Italian laureate
more cautious than ever, “non-committal about the fast-neutron bomb and
not altogether happy about the Bohr-Wheeler theory of fission.
”1462
Before or aer his meetings in Washington and New York Oliphant visited
William D.
Coolidge, the temporary chairman who produced the second
NAS report, at General Electric in Schenectady.
at visit at least stirred
something like indignation.
Coolidge immediately wrote Jewett of Oliphant’s
news, emphasizing for pure U235 “that the chain reaction in this case would
take place thru the direct action of fast neutrons....
is information, so far
as I know, was not available in this country until aer the National Academy
Committee had sent in its second report.
I think that Oliphant’s story should
be given serious consideration.
”1463 Information had indeed been available
in the United States—at least the MAUD minutes, including Peierls’ April 9
statement—but Briggs had locked it away for safekeeping.
Oliphant returned
to Birmingham wondering if he had made any impression at all.
Lawrence was already moving.
He called Arthur Compton in Chicago
aer Oliphant le Berkeley.
“Certain developments made him believe it
would be possible to make an atomic bomb,” Compton paraphrases the
conversation.
“Such a bomb, if developed in time, might determine the
outcome of the war.
e activity of the Germans in this field made it seem to
him a matter of great urgency for us to press its development.” 1464 It was no
more than Szilard had argued two years earlier.
Lawrence was scheduled to
speak in Chicago on September 25.
Conant would be in town to receive an
honorary degree.
Compton proposed to invite both men together to his
home.
Lawrence could then press the NDRC chairman directly.
* * *
Following his decision for political commitment at the Pan American
Scientific Conference, Edward Teller had continued teaching at George
Washington University but sought work in fission research.
In March 1941,
with Merle Tuve as one of their sponsors, the Tellers swore allegiance to the
United States and became American citizens.
Hans Bethe, who was teaching
at Columbia for the spring term on temporary leave from Cornell, took the
oath the same month.
At the end of the term Bethe recommended that
Columbia invite Teller to replace him.
To work more closely with Fermi and
Szilard—and to adjudicate their disputes, which he did with sensitivity—
Teller accepted and moved to Manhattan, to an apartment on Morningside
Drive.
In the midst of experiment Fermi found time to theorize.
He and Teller
had lunch at the University Club one pleasant day in September.
Aerward,
walking back to Pupin—“out of the blue,” Teller says—Fermi wondered
aloud if an atomic bomb might serve to heat a mass of deuterium sufficiently
to begin thermonuclear fusion.1465 Such a mechanism, a bomb fusing
hydrogen to helium, should be three orders of magnitude as energetic as a
fission bomb and far cheaper in terms of equivalent explosive force.
For
Fermi the idea was a throwaway.
Teller found it a surpassing challenge and
took it to heart.
Teller liked to break new ground.
When he understood something
theoretically he usually moved on without waiting for experimental
confirmation.
He understood the atomic bomb.
He moved on to consider
the possibility of a hydrogen bomb.
He made extensive calculations.
ey
were disappointing.
“I decided that deuterium could not be ignited by
atomic bombs,” he recalls.
1466 “Next Sunday, we went on a walk.
e Fermis
and the Tellers.
1467 And I explained to Enrico why a hydrogen bomb could
never be made.
And he believed me.” For a while, Teller even believed
himself.
Enrico Fermi and Edward Teller were not, however, the first to conceive of
using a nuclear chain reaction to initiate a thermonuclear reaction in
hydrogen.
at distinction apparently belongs to Japanese physicist
Tokutaro Hagiwara of the faculty of science of the University of Kyoto.
Hagiwara had followed world fission research and had conducted studies of
his own.
In May 1941 he lectured on “Super-explosive U235,” reviewing
existing knowledge.
1468, 1469 He was aware that an explosive chain reaction depended on U235 and understood the necessity of isotope separation:
“Because of the potential application of this explosive chain reaction a
practical method of achieving this must be found.
Immediately, it is very
important that a means of manufacturing U-235 on a large scale from
natural uranium be found.” He then discussed the linkage he saw between
nuclear fission and thermonuclear fusion: “If by any chance U-235 could be
manufactured in a large quantity and of proper concentration, U-235 has a
great possibility of becoming useful as the initiating matter for a quantity of
hydrogen.
We have great expectations for this.”
But before the Japanese or the Americans could build a hydrogen bomb
they would have to build an atomic bomb.
And in neither country was
major support yet secure.
* * *
“It was a cool September evening,” Arthur Compton remembers.
“My wife
greeted Conant and Lawrence as they came into our home and gave each of
us a cup of coffee as we gathered around the fireplace.
en she busied
herself upstairs so the three of us might talk freely.” 1470
Lawrence spoke with passion.
He was “very vigorous in his expression of
dissatisfaction with the U.S.
program,” writes Conant.
“Dr.
Oliphant had
seen him during the summer and by recounting the British hopes had
further fired Lawrence’s zeal for more action in this whole field.” 1471 Conant
knew all about the British hopes, knew talk was cheap and chose to play the
devil’s advocate, easily gulling Compton, who thought his arguments turned
the tide:
Conant was reluctant.
As a result of the reports so far received he had
concluded that the time had come to drop the support of nuclear research
as a subject for wartime study....
We could not afford to spend either our
scientific or our industrial effort on an atomic program of highly
questionable military value when every ounce of our strength was needed
for the nation’s defense.
I rallied to Lawrence’s support....
Conant began to be convinced.1472
“I could not resist the temptation,” says the Harvard president, “to cut
behind [Lawrence’s] rhetoric by asking if he was prepared to shelve his own
research programs.” 1473 Compton cranks Conant’s challenge to high
melodrama:
“If this task is as important as you men say,” [Conant] remarked, “we must
get going.
I have argued with Vannevar Bush that the uranium project be
put in wraps for the war period.
Now you put before me plans for making
a definite, highly effective weapon.
If such a weapon is going to be made,
we must do it first.1474 We can’t afford not to.
But I’m here to tell you,
nothing significant will happen on such a job as this unless we get into it
with everything we’ve got.”
He turned to Lawrence.
“Ernest, you say you are convinced of the
importance of these fission bombs.
Are you ready to devote the next
several years of your life to getting them made?”
...
e question brought Lawrence up with a start.
I can still recall the
expression in his eyes as he sat there with his mouth half open.
Here was a
serious personal decision....
He hesitated only a moment: “If you tell me
this is my job, I’ll do it.”
Back in Washington Conant briefed Bush on what he calls “the results of
the involuntary conference in Chicago to which [I] had been exposed.” 1475
e two administrators decided to order up a third National Academy
report, enlarging Compton’s committee this time to include W.
K.
Lewis, a
chemical engineer with an outstanding reputation for estimating the
potential success at industrial scale of laboratory processes, and Conant’s
Harvard colleague George B.
Kistiakowsky, the resident NDRC explosives
expert.
Tall, big-boned, boisterous, with a flat Slavic face and abiding
selfconfidence, Kistiakowsky had volunteered at eighteen for the White
Russian Army and fought in the Russian Revolution.
“I grew up in a family
in which the question of civil rights, human freedom, was an important
one,” he told an interviewer late in life.
“My father was a professor of
sociology and wrote articles and books on the subject and got into trouble
with the Czar’s regime, very substantial trouble.
Mother was also politically
oriented.
I think both of them went through a short period of being
Marxists and then rejected it.
at’s why I really joined the anti-Bolshevik
armies in ‘18.
It was certainly not because I loved Czarism.
Of course, I got
completely disgusted with the White Army long before it was all over.”
Kistiakowsky escaped to Germany and took his doctorate at the University
of Berlin in 1925.
He might have stayed, but his professor advised him to
look elsewhere.
“He told me that if I wanted to go into an academic career I
should emigrate; I would never get a job in Germany—’Here you will always
be a Russian.’ ” 1476 Princeton accepted the Ukrainian chemist on a
fellowship and soon hired him for its faculty.
en Harvard discovered and
courted him.
In 1930 he moved, becoming professor of chemistry in 1938.
Conant had been among those who lured Kistiakowsky from Princeton to
Harvard.
He valued highly his friend and fellow chemist’s opinion.
“When I
retailed to him the idea that a bomb could be made by the rapid assembly of
two masses of fissionable material, his first remark was that of a doubting
omas.
‘It would seem to be a difficult undertaking on a battlefield,’ he
remarked.” But it was Kistiakowsky’s judgment that finally convinced
Conant, as British hopes and physicists’ entreaties had not:
A few weeks later when we met, his doubts were gone.
“It can be made to
work,” he said.
“I am one hundred percent sold.”
My doubts about Briggs’ project evaporated as soon as I heard George
Kistiakowsky’s considered verdict.
I had known George for many
years....
I had asked him to be head of the NDRC division on
explosives....
I had complete faith in his judgment.
If he was sold on
Arthur Compton’s program, who was I to have reservations?1477
Oliphant convinced Lawrence, Lawrence convinced Compton,
Kistiakowsky convinced Conant.
Conant says Compton’s and Lawrence’s
attitudes “counted heavily with Bush.” But “more significant” was the MAUD
Report, which G.
P.
omson, now British scientific liaison officer in
Ottawa, officially transmitted to Conant on October 3.
1478 On October 9,
without waiting for the third National Academy of Sciences review, Bush
carried the report directly to the President.
Franklin Roosevelt, Henry Wallace and the director of the OSRD met that
ursday at the White House.
In a memorandum Bush wrote to Conant the
same day he makes it clear that the MAUD Report was the basis for the
discussion: “I told the conference of the British conclusions.” 1479 He told the
President and the Vice President that the explosive core of an atomic bomb
might weigh twenty-five pounds, that it might explode with a force
equivalent to some eighteen hundred tons of TNT, that a vast industrial
plant costing many times as much as a major oil refinery would be necessary
to separate the U235, that the raw material might come from Canada and
the Belgian Congo, that the British estimated the first bombs might be ready
by the end of 1943.
Bush tried to explain that an atomic bomb plant would
produce no more than two or three bombs a month but doubted if the
President took in that “relatively low yield.” He emphasized that he was
basing his statements “primarily on calculation with some laboratory
investigation, but not on a proved case” and therefore could not guarantee
success.
Bush was presenting, essentially, British calculations and British
conclusions.
Such a presentation made it appear that Britain was further
advanced in the field than America.
e discussion therefore shied to the
question of how the United States was attached or might attach itself to the
British program.
“I told of complete interchange with Britain on technical
matters, and this was endorsed.” Bush explained that the “technical people”
in Britain had also formulated policy—had proposed that the government
develop the atomic bomb as a weapon of war—and had passed their
formulations along directly to the War Cabinet.
In the United States, Bush
said, an NDRC section and an advisory committee considered technical
matters and only he and Conant considered policy.
Policy was the President’s prerogative.
As soon as Bush exposed it to view
Roosevelt seized it.
Bush took that decision to be the most important
outcome of the meeting and put it emphatically first in his memorandum to
Conant.
Roosevelt wanted policy consideration restricted to a small group
(it came to be called the Top Policy Group).
He named its members: Vice
President Wallace, Secretary of War Henry L.
Stimson, Army Chief of Staff
George C.
Marshall, Bush and Conant.
Every man owed his authority to the
President.
Roosevelt had instinctively reserved nuclear weapons policy to
himself.
us at the outset of the U.S.
atomic energy program scientists were
summarily denied a voice in deciding the political and military uses of the
weapons they were proposing to build.
Bush accepted the usurpation
happily.
To him it was simply a matter of who would run the show.
It le
him on top and inside and he put it to use immediately to shoulder the
physics community into line.
Within hours, as he wrote Frank Jewett in
November, he had “emphasized to Arthur Compton and his people the fact
that they are asked to report upon the techniques, and that consideration of
general policy has not been turned over to them as a subject.” 1480, 1481
Significantly, Bush associated the reservation of policy with relief from
criticism: “Much of the difficulty in the past has been due to the fact that
Ernest Lawrence in particular had strong ideas in regard to policy, and
talked about them generally....
I cannot....
bring him into the discussions,
as I am not authorized by the President to do so.” He applied just this test—
silence on policy—to measure Lawrence’s and Compton’s loyalty: “I think
[Lawrence] now understands this, and I am sure that Arthur Compton does,
and I think our difficulties in this regard are over.”
A scientist could choose to help or not to help build nuclear weapons.
at was his only choice.
e surrender of any further authority in the
matter was the price of admission to what would grow to be a separate,
secret state with separate sovereignty linked to the public state through the
person and by the sole authority of the President.
Patriotism contributed to many decisions, but a deeper motive among the
physicists, by the measure of their statements, was fear—fear of German
triumph, fear of a thousand-year Reich made invulnerable with atomic
bombs.
And deeper even than fear was fatalism.
e bomb was latent in
nature as a genome is latent in flesh.
Any nation might learn to command its
expression.
e race was therefore not merely against Germany.
As
Roosevelt apparently sensed, the race was against time.
ere are indications in Bush’s memorandum that Roosevelt was
concerned less with a German challenge than with the long-term
consequences of acquiring so decisive a new class of destructive
instruments.
“We discussed at some length aer-war control,” Bush wrote
Conant, “together with sources of raw material” (sources of raw material
were then believed to be few and far between; whoever commanded them
might well, it seemed, monopolize the bomb).
Roosevelt was thinking
beyond developing bombs for the war that the United States had not yet
entered.
He was thinking about a military development that would change
the political organization of the world.
Bush, who was a successful administrator partly because he knew the
limits of his charter, then suggested that a “broader program”—industrial
production—ought to be handled when the time came by some larger
organization than the OSRD.
Roosevelt agreed.
Summarizing his
assignment, Bush told the President he understood he was to expedite in
every possible way the necessary research but was “not [to] proceed with any
definite steps on this expanded plan until further instructions from him....
He indicated that this was correct.” e money, the President told him,
“would have to come from a special source available for such an unusual
purpose and...
he could arrange this.”
e United States was not yet committed to building an atomic bomb.
But
it was committed to exploring thoroughly whether or not an atomic bomb
could be built.
One man, Franklin Roosevelt, decided that commitment—
secretly, without consulting Congress or courts.
It seemed to be a military
decision and he was Commander in Chief.
* * *
Bush and Conant proceeded to order up from Arthur Compton a third NAS
review.
Compton asked Samuel Allison for the name of someone who could
help him calculate the critical mass of U235.
Allison had been
corresponding with Enrico Fermi on the subject of carbon absorption cross
sections and recommended him highly.
Compton “called on Fermi in his
office at Columbia University.
1482 Stepping to the blackboard he worked out
for me, simply and directly, the equation from which could be calculated the
critical size of a chain-reacting sphere.
He had at his fingertips the most
recent experimental values of the constants.
He discussed for me the
reliability of the data....
Even the most conservative estimate showed that
the amount of fissionable metal needed to effect a nuclear explosion could
hardly be greater than a hundred pounds.” 1
Compton moved on to Harold Urey’s office to look into isotope
separation.
Urey was the recognized world leader in the field as a result of
his Nobel Prize-winning work with hydrogen isotopes; he had directed
isotope separation studies for the Uranium Committee and the Naval
Research Laboratory since the beginning.
He personally investigated
chemical separation of U235 (which turned out to be impossible given the
chemical compounds of the day) and separation by centrifuge.
Estimating
that a centrifuge plant that would produce one kilogram of U235 per day
would require 40,000 to 50,000 yard-long centrifuges and would cost about
$100 million, he had recently contracted with Westinghouse in the name of
the Uranium Committtee for a prototype unit.
Urey was initially skeptical of gaseous barrier diffusion.
He and John
Dunning were not compatible, perhaps because they were both enthusiasts,
and only when centrifuge development was well under way, in late 1940, did
Urey turn his attention to the process that Dunning and Eugene Booth were
working hard at their own expense to develop.
ey had chosen gaseous
diffusion at dinner one evening in 1940 on their way home from a trip to
Schenectady by systematically ruling out other methods as unsuitable for
large-scale production, much as Peierls and Simon had done.
1483 ey were
interested in nuclear power, Booth remembers, not bomb-making.
“Our
reasons for pursuing the isotope separation path toward power production
were simple and general.
If a chain reaction became possible with normal
uranium, a smaller and probably cheaper power plant could be made with
enriched uranium.
”1484
Dunning and Urey produced a joint appraisal of the gaseous-diffusion
process in November 1940.
Dunning’s barrier material at the time was
fritted glass—partially fused and therefore porous silica, the material from
which porcelain is made—which uranium hexafluoride was likely to
corrode.
1485 ey estimated that a gaseous-diffusion plant would involve
some five thousand separate barrier tanks—“stages”—but made no attempt
to determine cost and power requirements.
By the autumn of 1941, without official support, Dunning and Booth had
nevertheless made significant progress.
ey had switched to brass barriers
from which the zinc had been etched (brass is an alloy of copper and zinc;
etching away the zinc made the material porous).
In November, the month
aer Compton’s visit, they would successfully enrich a measurable quantity
of uranium with their equipment.
Compton traveled next to Princeton to see Eugene Wigner, who had been
working closely with Fermi.
Wigner clarified for Compton the difference
between fast- and slow-neutron fission.
He endorsed the uraniumgraphite
system Fermi was developing as a method for producing 94.
“He urged me,”
writes Compton, “almost in tears, to help get the atomic program rolling.
His lively fear that the Nazis would make the bomb first was the more
impressive because from his life in Europe he knew them so well.” 1487
Back in Chicago Compton talked to Glenn Seaborg, who had come east
from Berkeley at Compton’s request.
Seaborg was confident he could devise
a large-scale, remote-controlled technology for separating 94 chemically
from uranium.
Armed with this new round of information Compton called a meeting of
his committee for October 21 in Schenectady.
1488 He prepared for the
meeting by writing a dra report.
A letter came from Lawrence saying he
wanted to bring along Robert Oppenheimer: “I have a great deal of
confidence in Oppie, and I’m anxious to have the benefit of his judgment in
our deliberation.” 1489 Conant had scolded Lawrence at Compton’s fireside
when he learned that Lawrence had asked Oppenheimer, still an outsider,
for help with theory, but now Lawrence’s request was granted.1490
A dispute between Lawrence and Oppenheimer about what Lawrence
called the theoretician’s “lewandering activities” almost excluded him from
the atomic bomb project.
1491 Oppenheimer, married now to the former
Katherine Puening, known as Kitty, with a six-month-old son, had begun to
wish for assignment.
“Many of the men I had known went off to work on
radar and other aspects of military research,” he testified later.
“I was not
without envy of them.
”1492 He learned the price of admission when he
invited Lawrence to an organizational meeting at his elegant new home on
Eagle Hill for a professional union, the American Association of Scientific
Workers, of which Arthur Compton, among others, was a senior member.
Lawrence wanted no part in any “causes and concerns,” as he called political
activities, and barred his staff as well: “I don’t think it’s a good idea,” he told
them.
1493 “I don’t want you to join it.
I know nothing wrong with it, but
we’re planning big things in connection with the war effort, and it wouldn’t
be right.
I want no occasion for somebody in Washington to find fault with
us.” Oppenheimer was not so easily put off; he debated Lawrence’s point,
arguing that humanity was everyone’s responsibility and that the more
fortunate should help “underdogs.” e Nazis came first, Lawrence
countered.
1494 He told Oppenheimer about Conant’s scolding.
Oppenheimer reserved judgment.
e October 21 meeting, where he could
measure the scientific leaders of the uranium program against his own
formidable gis, changed his mind.
“It was not until my first connection
with the rudimentary atomic-energy enterprise,” he testifies, “that I began to
see any way in which I could be of direct use.
”1495 When he saw his way to
war work he quickly sacrificed his underdogs, writing Lawrence on
November 12:
I...
assure you that there will be no further difficulties at any time with
the A.A.S.W....
I doubt very much whether anyone will want to start at
this time an organization which could in any way embarrass, divide or
interfere with the work we have in hand.
I have not yet spoken to
everyone involved, but all those to whom I have spoken agree with us: so
you can forget it.1496
Lawrence opened the Schenectady meeting by reading Oliphant’s
summary of the MAUD Report.
Compton followed with a review based on
his October travels.
Oppenheimer weighed in during the discussion of
U235’s critical mass with an estimate of 100 kilograms, 220 pounds, close to
Fermi’s estimate of 130,000 grams.
“Kistiakowsky,” writes Compton,
“explained the great economic advantage of being able to deliver a heavy
blow with a bomb carried by a single plane.” 1497
But Compton was distressed to discover he could not move the engineers
on the review committee—the practical souls Bush had insisted be added to
bring the NAS reviews down to earth—to estimate either how much time it
would take to build a bomb or how much the enterprise would cost:
With one accord they refused....
ere weren’t enough data.
e fact was
that they had before them all the relevant information that existed, and
some kind of answer was needed, however rough it might be, for
otherwise our recommendation could not be acted upon.
Aer some
discussion, I suggested a total time of between three and five years, and a
total cost...
of some hundreds of millions of dollars.
None of the
committee members objected.
So the American numbers came out of a scientist’s hat, as the British
numbers had.
Atomic energy was still too new for engineering.
If Compton was distressed by the refusal of commitment, Lawrence was
appalled.
Within twenty-four hours he mailed the committee chairman a
bracing challenge edged with threat:
In our meeting yesterday, there was a tendency to emphasize the
uncertainties, and accordingly the possibility that uranium will not be a
factor in the war.
is to my mind, was very dangerous....
1498
It will not be a calamity if, when we get the answers to the uranium
problem, they turn out negative from the military point of view, but if the
answers are fantastically positive and we fail to get them first, the results
for our country may well be tragic disaster.
I feel strongly, therefore, that
anyone who hesitates on a vigorous, all-out effort on uranium assumes a
grave responsibility.
But Compton had already been threatened by an expert, Vannevar Bush,
and knew his duty well, though he did not yet know that Bush was already
committed to expedition and expansion.
He had difficulty estimating “the
destructiveness of the bomb.” e calculation “involved problems of gas
pressure, specific heats at hitherto unknown temperatures, the transmission
of radiations and particles through the material, and forces of inertia.” 1499
He asked Gregory Breit for help.
Breit was even more obsessed with secrecy
than Briggs.
“No help was forthcoming,” says Compton, gritting his teeth.
He turned then to Oppenheimer.
“I had known ‘Oppie’ for some fourteen
years and had found him most competent in seeing the essentials of an
intricate problem and in interpreting what he saw.
So I was glad to get a
letter from him with helpful suggestions.
”1500 rough the end of October
Compton worked on.
* * *
At Leipzig in September Werner Heisenberg received the first forty gallons
of heavy water from Norsk Hydro and immediately prepared another chain-
reaction experiment like the unsuccessful effort at the Virus House in
Dahlem the year before: a thirty-inch aluminum sphere filled with
alternating layers of heavy water and uranium oxide, more than three
hundred pounds of it, arranged around a central neutron source, the sphere
itself then immersed in water in a laboratory tank.
is time Heisenberg
found some increase in neutrons, enough to extrapolate eventual success.
e German laureate knew now from the work of von Weizsácker and
Houtermans that a sustained chain reaction in natural uranium would breed
element 94.
“It was from September 1941,” he remarks in consequence, “that
we saw an open road ahead of us, leading to the atomic bomb.
”1501
He decided to talk to Bohr.
To what end he thought Bohr might help him
he never unambiguously explained.
His wife Elisabeth believes “he was
lonely in Germany.
Niels Bohr had become a father figure to him....
He
thought that he could talk about anything with Bohr....
e advice of an
older friend, more experienced in human and political affairs, had always
been important to him.” He “saw himself confronted with the spectre of the
atomic bomb,” Elisabeth Heisenberg explains, “and he wanted to signal to
Bohr that Germany neither would nor could build a bomb....
Secretly he
even hoped that his message could prevent the use of an atomic bomb on
Germany one day.
He was constantly tortured by this idea....
is vague
hope was probably the strongest motivation for his trip.
”1502
Heisenberg and von Weizsäcker attended a scientific meeting in
Copenhagen at the end of October, a meeting Bohr routinely boycotted as
he boycotted all joint Danish and German activities, to emphasize his refusal
to collaborate.
He was willing to see Heisenberg, however, and received him,
according to the German physicist’s wife, “with great warmth and
hospitality.
”1503
Heisenberg saved his crucial conversation for a long evening walk with
Bohr through the brewery district around the Carlsberg House of Honor.
“Being aware that Bohr was under the surveillance of the German political
authorities,” he recalled aer the war, “and that his assertions about me
would probably be reported to Germany, I tried to conduct this talk in such
a way as to preclude putting my life into immediate danger.” Heisenberg
remembers asking Bohr if it was right for physicists to work on “the
uranium problem” in wartime when there was a possibility that such work
could lead to “grave consequences in the technique of war.” Bohr, who had
returned from the United States convinced that a bomb was practically
impossible, “understood the meaning of the question immediately, as I
realized from his slightly frightened reaction.” Heisenberg apparently
thought Bohr was privy to American secrets and was reacting guiltily to
implicit exposure.
But Bohr’s next response suggests that he had been,
rather, stunned at Heisenberg’s revelation: he asked Heisenberg if a bomb
really was possible.
Heisenberg says he answered that a “terrific technical
effort” would be necessary, which he hoped could not be realized in the
present war.
“Bohr was shocked by my reply, obviously assuming that I had
intended to convey to him that Germany had made great progress in the
direction of manufacturing atomic weapons.
Although I tried subsequently
to correct this false impression I probably did not succeed....
I was very
unhappy about the result of this conversation.” 1504
us Heisenberg’s version of the evening walk.
Bohr’s is less detailed.
His
son Aage, a Nobel laureate in his turn and his father’s successor as director
of the Copenhagen institute, summarizes it in a memoir:
e impression that in Germany great military importance was given to
[atomic energy research] was strengthened by the visit to Copenhagen in
the autumn of 1941 of Werner Heisenberg and C.
F.
von Weizsäcker....
In a private conversation with my father Heisenberg brought up the
question of the military applications of atomic energy.
My father was very
reticent and expressed his scepticism because of the great technical
difficulties that had to be overcome, but he had the impression that
Heisenberg thought that the new possibilities could decide the outcome of
the war if the war dragged on....
[Heisenberg’s] account [of the meeting]
has no basis in actual events.1505
Robert Oppenheimer, who also had the story direct from Bohr, condenses
the meeting to the comment: “Heisenberg and von Weizsäcker came over
from Germany, and so did others.
Bohr had the impression that they came
less to tell what they knew than to see if Bohr knew anything that they did
not; I believe that it was a standoff.” 1506
e two accounts are not incompatible, but both leave out a crucial fact:
that Heisenberg passed to Bohr a drawing of the experimental heavywater
reactor he was working to build.1507 If he did so clandestinely he certainly
risked his life.
If he did so cynically and with Nazi approval to misdirect
Allied intelligence he was certainly no longer attached to Bohr as a father
figure, as Elisabeth Heisenberg writes.
Whatever his intent, it had the wrong
effect on Bohr.
Elisabeth Heisenberg thinks “Bohr essentially heard only one
single sentence: e Germans knew that atomic bombs could be built.
He
was deeply shaken by this, and his consternation was so great that he lost
track of all else.” 1508 But Aage Bohr’s and Oppenheimer’s accounts imply a
further response from Bohr: indignation, even incredulity, that Heisenberg
would think Bohr might be willing in any way, for any reason, to cooperate
with Nazi Germany.
Heisenberg, in turn, was aghast that Bohr would fail to
see and credit his reservations, would not understand, as his wife writes, that
his “bond to his country and its people was not tantamount to a bond to the
regime.” To the contrary, she adds, “Bohr told Heisenberg that he
understood completely that one had to use all of one’s abilities and energies
for one’s country in time of war.” Not surprisingly, since it implied Bohr
thought the worst of him—that he was willing to work for the Nazis
—“Heisenberg was deeply shocked by Bohr’s reply.
”1509
e meeting, and especially the drawing Heisenberg passed, gave Bohr
more to worry about, but he continued to doubt that any nation could afford
sufficient industrial capacity, especially in wartime, to pursue isotope
separation.
He must have been pained at what he took to be the treachery of
a brilliant and formerly devoted protege.
Heisenberg for his part found
himself, says his wife, in “a state of confusion and despair.” 1510 Even at risk
he had not convinced Bohr of his sincerity nor in any way begun a dialogue
to avert possible catastrophe.
In the absence of such dialogue he had only
managed potentially to alarm Germany’s most powerful enemy further with
news of progress in approaching the chain reaction.
at news must
necessarily accelerate Allied efforts to build a bomb.
As Rudolf Peierls writes
of this period in Heisenberg’s life, “he had agreed to sup with the devil, and
perhaps he found that there was not a long enough spoon.
”1511
* * *
Arthur Compton sent dra copies of the third National Academy of
Sciences report to Vannevar Bush and Frank Jewett before the weekend of
November 1.
e new report was brief—six double-spaced typewritten
pages (with forty-nine pages of technical appendices and figures)—and
finally and emphatically to the point: “e special objective of the present
report is to consider the possibilities of an explosive fission reaction with
U235” Progress toward separating uranium isotopes, Compton wrote, made
renewed consideration urgent (a rationale somewhat less than candid:
British progress had spurred the change).
1512, 1513
is time the report knew what it was about: “A fission bomb of superlative
destructive, power will result from bringing quickly together a sufficient mass
of element U235.
is seems to be as sure as any untried prediction based
upon theory and experiment can be.” 1514 On the second page an estimate of
critical mass elicited for the first time among the three NAS reports a
mention of fast fission: “e mass of U235 required to produce explosive
fission under appropriate conditions can hardly be less than 2 kg nor greater
than 100 kg.
ese wide limits reflect chiefly the experimental uncertainty in
the capture cross-section of U235 for fast neutrons.
”1515
e NAS estimate of destructiveness was low compared to the MAUD
Report estimate, some 30 tons of TNT equivalent per kilogram of U235 (for
25 pounds, 300 tons compared to MAUD’s 1,800 tons), but the American
report attempted to compensate for its doubts about the efficacy of an
intense energy release from a small amount of matter by emphasizing that
the destructive effects on life of a bomb’s radioactivity “may be as important
as those of the explosion itself.
”1516
e centrifuge and gaseous diffusion programs were noted to be
“approaching the stage of practical test.
”1517 Fission bombs might be
available “in significant quantity within three or four years.” 1518 Like its
predecessors the report stressed not the German challenge but the long-
term prospect: “e possibility must be seriously considered that within a
few years the use of bombs such as described here, or something similar
using uranium fission, may determine military superiority.
1519 Adequate
care for our national defense seems to demand urgent development of this
program.”
In detailed appendices Compton calculated the critical mass of a bomb
heavily constrained in tamper at no more than 3.4 kilograms; Kistiakowsky
debated whether a fission explosion would be as destructive in terms of
energy produced as the explosion of an equivalently energetic mass of TNT
and confirmed the feasibility of firing together two pieces of uranium at a
speed of several thousand feet per second; and a senior physicist on
Compton’s committee reported favorably on the isotope-separation systems
then under consideration and recommended “the principle of parallel
development,” meaning pursuing them all at once, an expensive way to save
time in case one or more failed.
Notably missing from the third report was any mention of the uranium-
graphite work going on at Columbia or of plutonium.
Compton remembers
that a U235 bomb looked “more straightforward and more certain of
accomplishment” than a plutonium bomb, but the omission also measures
the extent to which Briggs’ judgment of priorities, and Briggs himself, had
been set aside.
1520 Bush writing Jewett before he met with Compton had
already mentioned “leaving Briggs in charge of a section devoted as it is at
the present time to physical measurements”—small potatoes indeed—and
constituting “a new group under a full-time head to handle development.”
He was considering Ernest Lawrence but still thought Lawrence talked too
much: “e matter...
would have to be handled under the strictest sort of
secrecy.
1521 is is the reason that I hesitate at the name of Ernest
Lawrence.”
If the third and last NAS report only rationalized a previous presidential
decision, it at least served to check the British findings independently and to
commit the American physics community to the cause.
e United States
had finally set its wheels to the bomb track.
Its inertia was proportional to
the juggernaut of its scientific, engineering and industrial might.
Acceleration overcoming inertia, it now began to roll.
* * *
No document Franklin Delano Roosevelt signed authenticates the fateful
decision to expedite research toward an atomic bomb that Vannevar Bush
reported in his October 9 memorandum to James Bryant Conant: the
archives divulge no smoking gun.
e closest the records come to a piece of
paper that changed the world is a banality.
Bush personally delivered the
third National Academy of Sciences report to the President on November
27, 1941.
Roosevelt returned it to him two months later with a note on
White House stationery written in black ink with a broad-nibbed pen, a note
that would communicate only a commonplace of the housekeeping of state
secrets except for the authority of its first vernacular expression and the
initials it bears:
Text reads: “Jan 19—V.B.
OK—returned—I think you had best keep this in your own safe
FDR”1522
Still orphaned was plutonium, which Lawrence and Compton believed so
promising.
Compton found his chance to speak for it in early December
when Bush and Conant called the members of the Uranium Committee to
Washington to announce the reorganization of their work.
Harold Urey
would develop gaseous diffusion at Columbia, Bush and Conant had
decided.
Lawrence would pursue electromagnetic separation at Berkeley.
A
young chemical engineer, Eger V.
Murphree, the director of research for
Standard Oil of New Jersey, would supervise centrifuge development and
look into broader questions of engineering.
Compton in Chicago would be
responsible for theoretical studies and the actual design of the bomb.
“e
meeting adjourned,” writes Compton, “with the understanding that we
would meet again in two weeks to compare progress and shape our plans
more firmly.
”1523
Bush, Conant and Compton went to lunch at the Cosmos Club on
Lafayette Square.
ere the Chicago physicist spoke up for plutonium.
He
argued that the advantage of chemical extraction rather than isotope
separation made element 94 “a worthy competitor.” Bush was wary.
Conant
pointed out that the new element’s chemistry was still largely unknown.
1524
Compton recalls their exchange:
“Seaborg tells me that within six months from the time [plutonium] is
formed [by chain reaction] he can have it available for use in the bomb,”
was my comment.
“Glenn Seaborg is a very competent young chemist, but he isn’t that
good,” said Conant.
How good a chemist Glenn Seaborg might be remained to be seen.
Compton, Conant remembers, went on to argue that “the construction of a
self-sustaining chain reaction [in natural uranium—Fermi’s and Szilard’s
project]1525 would be a magnificent achievement” even if plutonium flunked
as bomb material; “it would prove that the measurements and theoretical
calculations were correct”:
I never knew whether it was this near-certainty of demonstrating a slow-
neutron reaction which settled the matter in Van’s mind, or whether he
was impressed with Compton’s faith in the production of a plutonium
bomb, against my lack of faith as a chemist.
At all events, within a matter
of weeks he agreed to Arthur Compton’s setting up at Chicago a highly
secret project.
Bush had called the Washington meeting on a weekend to accommodate
busy men.
ey had assembled on Saturday, December 6, 1941.
Almost
immediately they found themselves busier yet.
* * *
At 7 A.M.
Hawaiian time on Sunday, December 7, 1941, near Kahuku Point at
the northernmost reach of the island of Oahu, two U.S.
Army privates in the
process of shutting down the Opana mobile radar station, an aircra
reconnaissance unit which they had manned since 4 A.M., noticed an
unusual disturbance on their oscilloscope screen.1526 ey checked and
confirmed no malfunction and decided the large merged blur of light “must
be a flight of some sort.” eir plotting board indicated a bearing out of the
northeast at a distance of 132 miles.
More than fiy planes appeared to be
involved.
One of the men called the information center at Fort Shaer, at the
other end of the island, where radar and visual reconnaissance reports were
combined on a tabletop map.
e lieutenant who took the phone heard the
radar operator call the sightings “the biggest...
he had ever seen.
”1527 e
operator did not, however, report his estimate of their number.
Both the Army and the Navy had been warned of imminent danger of
Japanese attack.
e Japanese had convinced themselves that dominance
over East Asia was vital to their survival.
e American reaction to militant
Japanese expansion into Manchuria and China—as many as 200,000 men,
women and children were brutally slaughtered by the Japanese Army in
Shanghai in 1937—had been to embargo war materials and freeze Japanese
assets in the United States.
Aviation fuel, steel and scrap iron went on the
embargo list in September 1940 when the Japanese moved into French
Indochina with the timid approval of Vichy France.
Aer that the Japanese
estimated they could survive no more than eighteen months without access
to Asian oil and iron ore.
For some time they had prepared for war while
continuing to negotiate.
Now negotiations had collapsed.
Lieutenant General Walter C.
Short, commander of the Army’s Hawaiian
Department, received a coded message on November 27 signed in the name
of the Chief of Staff—George Marshall—that read in part:
Negotiations with Japan appear to be terminated to all practical purposes
with only the barest possibility that the Japanese Government might come
back and offer to continue.
Japanese future action unpredictable but
hostile action possible at any moment.
If hostilities cannot, repeat cannot
be avoided the United States desires that Japan commit the first overt
act....
Measures should be carried out so as not, repeat not, to alarm civil
population or disclose intent.1528
Short had at option three levels of alert, escalating from “a defense against
sabotage, espionage and subversive activities without any threat from the
outside” to full defense against “an all-out attack.” He thought it obvious that
the War Department message “was written basically for General Mac-
Arthur in the Philippines” and chose the limited sabotage defense, Alert No.
1.
1529
Admiral Husband E.
Kimmel, Commander in Chief of the U.S.
Pacific
Fleet, which was based at Pearl Harbor west of Honolulu on the southern
coast of Oahu, received a similar but even more pointed message from the
Navy Department a few hours later:
is dispatch is to be considered a war warning.
Negotiations with Japan
looking toward stabilization of conditions in the Pacific have ceased and
an aggressive move by Japan is expected within the next few days.
e
number and equipment of Japanese troops and the organization of naval
task forces indicates an amphibious expedition against either the
Philippines, ai or Kra Peninsula or possibly Borneo.
Execute an
appropriate defensive deployment preparatory to carrying out the tasks
assigned.1530
Kimmel noted the references to other theaters of potential conflict.
When he
and Short exchanged messages he noted the “more cautious phrasing” of the
Army warning.1531 “Appropriate defensive deployment” meant, he thought,
full security measures for ships at sea.
A surprise submarine attack seemed
possible and he ordered the depth-bombing of any submarines discovered in
the waters around Oahu.
e Army lieutenant who took the Opana radar call therefore had no
expectation of danger.
He looked for a routine explanation of the unusual
report and found it.
e Army paid radio station KGMB in Honolulu to play
Hawaiian music throughout the night whenever it ferried aircra to the
Islands, giving its navigators a signal to seek.
e lieutenant had heard such
music on the radio that morning on his way to the information center.
He
decided that the radar must be picking up a flight of B-17’s.
e heading
plotted at Opanu was the usual direction of approach from California.
“Well,
don’t worry about it,” the lieutenant told the radar men.1532
Pearl Harbor is a shallow, compound basin sheltered inland through a
narrow outer channel from the sea.
A bulge of land, Pearl City, and a
midbasin island, Ford Island, canalize the main anchorage of the harbor into
a loop of narrow inlets.
In 1941 drydocks, oil storage tanks and a submarine
base occupied the harbor’s irregular eastern shore.
Seven battleships rode at
anchor immediately southeast of Ford Island that Sunday morning: Nevada
anchored alone; Arizona inboard of the repair ship Vestal; Tennessee inboard
of West Virginia; Maryland inboard of Oklahoma; California alone.
An
eighth battleship, Pennsylvania, wedged naked in drydock nearby.
Lieutenant Commander Mitsuo Fuchida of the Japanese Imperial Navy,
thirty-nine years old, who wore a red shirt to disguise from his men any
blood he might shed and a white hachimaki tied around his flight helmet
brushed with the calligraphic characters for “Certain Victory,” called out
“Tora!
Tora!
Tora!” at 0753 hours as his pilot banked around Barber’s Point
southwest of Pearl: “Tiger!” three times invoked to announce to the listening
Japanese Navy that his first wave of 183 planes had achieved complete
surprise.
e 43 fighters, 49 high-level bombers, 51 dive-bombers and 40
torpedo planes he commanded had flown from six carriers holding station
200 miles to the north, carriers formidably escorted by battleships, heavy
cruisers, destroyers and submarines that had le Hitokappu Bay on the
northern Japanese island of Etorofu on November 25 and sailed blacked out
in radio silence across the stormy but empty northern Pacific for almost two
weeks to achieve this stunning rendezvous.
e torpedo bombers divided into groups of twos and threes and dived.
e aircrews had prepared themselves to ram the battleships if necessary,
but nothing restrained their attack.
At 0758 the Ford Island command center
radioed its frantic message to the world: AIR RAID PEARL HARBOR.
THIS IS NOT
DRILL.
Admiral Kimmel saw the attack begin from a neighbor’s lawn—“in
utter disbelief and completely stunned,” the neighbor remembers, “as white
as the uniform he wore.” Torpedoes struck a light cruiser and a target ship, a
minelayer, another light cruiser, then the battleships: Arizona lied out of
the water; West Virginia washed by a huge waterspout; Oklahoma hit by
three torpedoes one aer another and immediately listing steeply to port;
the bottom blown out of Arizona; three torpedoes into California; two more
into West Virginia’, a fourth into Oklahoma that bounced the big ship and
rolled it over bottom up; Arizona taking a bomb that detonated its forward
explosive stores, ripped the ship apart, killed at least a thousand men and
blew high into the air a grisly rain of bodies, hands, legs and heads; a
torpedo tearing out Nevada’s port bow.
ick black smoke rolled up to foul
the blue Hawaiian morning and in the water, burning, screaming men
attempted to swim through a dense scum of burning oil.
Japanese fighters
and bombers destroyed aircra on the ground and strafed soldiers and
marines pouring out of barracks at Hickam Field and Ewa Field and
Wheeler.
An hour later a second wave of 167 more attack aircra deployed
to further destruction.
e two raids accounted for eight battleships, three
light cruisers, three destroyers and four other ships sunk, capsized or
damaged and 292 aircra damaged or wrecked, including 117 bombers.
And
2,403 Americans, military and civilian, killed, 1,178 wounded, in
unprovoked assaults that lasted only minutes.
e following aernoon,
Franklin Roosevelt, addressing Congress in joint session, requested and won
a declaration of war against not only Japan but Germany and Italy as well.
e man who conceived and planned the surprise attack on Pearl Harbor,
Admiral Isoroku Yamamoto, Commander in Chief of the Japanese
Combined Fleet, had few illusions about the ultimate success of a war
against the United States.
He had studied at Harvard and served as a naval
attaché in Washington and knew America’s strength.
But if war had to come
he meant “to give a fatal blow to the enemy fleet” when it was least expected,
at the outset.
By that act he hoped he could win his country six months to a
year during which it might establish its Greater East Asia Co-Prosperity
Sphere and dig in.
e torpedoes had been a challenge.
Pearl Harbor was only forty feet
deep.
Torpedoes dropped from planes routinely sank seventy feet or more
before bobbing up to attack depth.
e Japanese had to reduce that plunge
signficantly or bury their weapons in the Pearl mud.
ey found in repeated experiments that they could sometimes manage a
shallower drop by flying only forty feet above the water and holding down
their air speed—the maneuver demanded skilled flying—but further
improvement required torpedo redesign, largely by trial and error.
As late as
mid-October Fuchida’s flyers were still managing no better than sixtyfoot
plunges, still far too deep.
A new stabilizer fin, originally designed for aerial stability, saved the
mission.
Tested during September, it consistently held the torpedo to less
than forty feet and steadied it as well.
But the pilots still needed aiming
practice.
Only thirty of the modified weapons could be promised by October
15, another fiy by the end of the month and the last hundred on November
30, aer the task force was scheduled to sail.
e manufacturer did better.
Realizing the weapons were vital to a secret
program of unprecedented importance, manager Yukiro Fukuda bent
company rules, drove his lathe and assembly crews overtime and delivered
the last of the 180 specially modified torpedoes by November 17.
Mitsubishi
Munitions contributed decisively to the success of the first massive surprise
blow of the Pacific War by the patriotic effort of its torpedo factory on
Kyushu, the southernmost Japanese island, three miles up the Urakami River
from the bay in the old port city of Nagasaki.
1533
13
The New World
Enrico Fermi’s team at Columbia University had been hard at work through
1941 while the government deliberated.
Fermi, Leo Szilard, Herbert
Anderson and the young physicists who had joined them may never have
known how close they came to orphanhood.
e isolation of plutonium at
Berkeley added a potential military application to their reasons for pursuing
a slow-neutron chain reaction in uranium and graphite, but given the
necessary resources Fermi at least would certainly have pursued the chain
reaction anyway as a physical experiment of fundamental and historic
worth.
He had missed discovering fission by the thickness of a sheet of
aluminum foil; he would not willingly leave to someone else the
demonstration of atomic energy’s first sustained release.
anks largely to
Arthur Compton his work found continued support, which may help
explain why he admired the pious Woosterite’s intelligence so extravagantly.
Szilard had finally gone on the Columbia payroll on November 1, 1940,
when the $40,000 National Defense Research Committee contract came
through for physical-constant measurements.
To help Fermi without the
friction the two men generated when they worked side by side, Szilard
undertook to apply his special talent for enlightened cajolery to the problem
of procuring supplies of purified uranium and graphite.
e record is thick
with his correspondence with American graphite manufacturers dismayed
to discover that what they thought were the purest of materials were in fact
hopelessly contaminated, usually with traces of boron.
e cross section for
neutron absorption of that light, ubiquitous, silicon-like element, number 5
on the periodic table, was tremendous and poisonous.
“Szilard at that time
took extremely decisive and strong steps to try to organize the early phases
of production of pure materials,” says Fermi.
“...
He did a marvelous job
which later on was taken over by a more powerful organization than was
Szilard himself.
Although to match Szilard it takes a few able-bodied
customers.
”1534
In August and September the Columbia team prepared to assemble the
largest uranium-graphite lattice yet devised.
A slow-neutron chain reaction
in natural uranium, like its fast-neutron counterpart U235, requires a
critical mass: a volume of uranium and moderator sufficient to sustain
neutron multiplication despite the inevitable loss of neutrons from its outer
surface.
No one yet knew the specifications of that critical volume, but it was
obviously vast—on the order of some hundreds of tons.
One way to create a
self-sustaining chain reaction might be simply to continue stacking uranium
and graphite together.
But so crude an experiment, if it worked at all, would
teach the experimenter very little about controlling the resulting reaction
and might culminate in a disastrous and lethal runaway.
Fermi proposed to
approach the problem by the more circumspect route of a series of
subcritical experiments designed to determine the necessary quantities and
arrangements and to establish methods of control.
As always, he built directly on previous experience.
He and Anderson had
calculated the absorption cross section of carbon by measuring the diffusion
of neutrons from a neutron source up a column of graphite.
e new
experiments would enlarge that column to take advantage of the increased
stocks of graphite available and to make room for regularly spaced
inclusions of uranium oxide: simplicity itself, but in physical form a thick,
black, grimy, slippery mass of some thirty tons of extruded bars of graphite
confining eight tons of oxide.1535 Fermi named the structure a “pile.” “Much
of the standard nomenclature in nuclear science was developed at this time,”
Segrè writes.1536 “...
I thought for a while that this term was used to refer to
a source of nuclear energy in analogy with Volta’s use of the Italian term pila
to denote his own great invention of a source of electrical energy [i.e., the
Voltaic battery].
I was disillusioned by Fermi himself, who told me that he
simply used the common English word pile as synonymous with heap” e
Italian laureate was continuing to master the plainsong of American speech.
e exponential pile Fermi proposed to build (so called because an
exponent entered into the calculation of its relationship to a full-scale
reactor) would be too big for any of the laboratories in Pupin.
He sought
larger quarters:
We went to Dean Pegram, who was then the man who could carry out magic around the
university, and we explained to him that we needed a big room.
And when we say big we meant a
really big room.
Perhaps he made a crack about a church not being the most suited place for a
physics laboratory...
but I think a church would have been just precisely what we wanted.
Well, he scouted around the campus and we went with him to dark corridors and under various heating
pipes and so on to visit possible sites for this experiment and eventually a big room, not a church,
but something that might have been compared in size with a church was discovered in
Schermerhorn [Hall].
ere, Fermi goes on, they began to build “this structure that at that time
looked again in order of magnitude larger than anything that we had seen
before....
It was a structure of graphite bricks and spread through these
graphite bricks in some sort of pattern were big cans, cubic cans, containing
uranium oxide.
”1537 e cans, 8 by 8 by 8 inches, 288 of them in all, were
made of tinned iron sheet; each could hold about 60 pounds of uranium
oxide.
1538 Each cubic “cell” of the uranium-graphite lattice—a can and its
surrounding graphite—was 16 inches on a side.
Spheres of uranium in an
arrangement of spherical cells would have been more efficient.
In these
beginning experiments, with materials of doubtful purity, Fermi was
pursuing order-of-magnitude estimates, a first rough mapping of new
territory.
“is structure was chosen because of its constructional
simplicity,” the experimenters wrote aerward, “since it could be assembled
without cutting our graphite bricks of 4” by 4” by 12”.
Although we did not
expect that the structure would approach too closely the optimum
proportions, we thought it desirable to obtain some preliminary information
as soon as possible.” 1539 Promising results might also win further NDRC
support.
“We were faced with a lot of hard and dirty work,” Herbert Anderson
recalls.
“e black uranium oxide powder had to be...
heated to drive off
undesired moisture and then packed hot in the containers and soldered
shut.
To get the required density, the filling was done on a shaking table.
Our
little group, which by that time included Bernard Feld, George Weil, and
Walter Zinn, looked at the heavy task before us with little enthusiasm.
It
would be exhausting work.
”1540 en Pegram to the rescue in Fermi’s telling:
We were reasonably strong, but I mean we were, aer all, thinkers.
So Dean Pegram again looked
around and said that seems to be a job a little bit beyond your feeble strength, but there is a football squad at Columbia that contains a dozen or so of very husky boys who take jobs by the
hour just to carry them through college.1541 Why don’t you hire them?
And it was a marvelous idea; it was really a pleasure for once to direct the work of these husky
boys, canning uranium—just shoving it in—handling packs of 50 or 100 pounds with the same
ease as another person would have handled three or four pounds.
“Fermi tried to do his share of the work,” Anderson adds; “he donned a lab
coat and pitched in to do his stint with the football men, but it was clear that
he was out of his class.
e rest of us found a lot to keep us busy with
measurements and calibrations that suddenly seemed to require exceptional
care and precision.” 1542
For this first exponential experiment and the many similar experiments to
come, Fermi defined a single fundamental magnitude for assessing the chain
reaction, “the reproduction factor k.” k was the average number of secondary
neutrons produced by one original neutron in a lattice of infinite size—in
other words, if the original neutron had all the room in the world in which
to dri on its way to encountering a uranium nucleus.
1543 One neutron in
the zero generation would produce k neutrons in the first generation, k2
neutrons in the second generation, k3 in the third generation and so on.
If k
was greater than 1.0 , the series would diverge, the chain reaction would go,
“in which case the production of neutrons is infinite.” If k was less than 1.0 ,
the series would eventually converge to zero: the chain reaction would die
out.
k would depend on the quantity and quality of materials used in the pile
and the efficiency of their arrangement.
e cubical lattice that the Columbia football squad stacked in
Schermerhorn Hall in September 1941 extrapolated to a disappointing first k
of 0.87.
“Now that is by 0.13 less than one,” Fermi comments—13 percent
less than the minimum necessary to make a chain reaction go—“and it was
bad.
However, at the moment we had a firm point to start from, and we had
essentially to see whether we could squeeze the extra 0.13 or preferably a
little bit more.” e cans were made of iron, and iron absorbs neutrons.
“So,
out go the cans.” Cubes of uranium were less efficient than spheres; next
time the Columbia group would press the oxide into small rounded lumps.
e materials were impure.
“So, now, what do these impurities do?—-clearly
they can do only harm.
Maybe they make harm to the tune of 13 percent.”
Szilard would continue his quest for materials of higher purity.
“ere was
some considerable gain to be made...
there.” 1544
“Well,” concludes Fermi, “this brings us to Pearl Harbor.”
* * *
Arthur Compton had less than two weeks to throw together a program
between his discussion with Vannevar Bush and James Bryant Conant at the
Cosmos Club luncheon on December 6 and the first meeting on December
18 of the new leaders of what was now to be called the S-l program.
(S-l for
Section One of the Office of Scientific Research and Development: Conant
would administer S-l, but the National Defense Research Committee was no
longer directly involved; the bomb program had advanced from research
into development.) On December 18, Conant notes in the secret history of
the project he wrote in 1943, “the atmosphere was charged with excitement
—the country had been at war nine days, an expansion of the S-l program
was now an accomplished matter.
Enthusiasm and optimism reigned.” 1545
Compton offered his program to Bush, Conant and Briggs the next day and
followed up on December 20 with a memorandum.1546 e projects that had
come under his authority were scattered across the country at Columbia,
Princeton, Chicago and Berkeley.
For the time being he proposed leaving
them there.
With the arrival of war, not to breathe a word of the mysteries they were
exploring, the project leaders had adopted an informal code: plutonium was
“copper,” U235 “magnesium,” uranium generically in the nonsensical British
coinage “tube alloy.” “On the basis of the present data,” Compton wrote,
optimism reigning, “it appears that explosive units of copper need be only
half the size of those using magnesium, and that premature explosions can
be ruled out.
”1547 Because of the difficulty of engineering a remotely
controlled chemical plant to extract plutonium, however, he thought that
“the production of useful quantities of copper will take longer than the
production of magnesium.” For a timetable he offered:
Knowledge of conditions for chain reaction by June 1, 1942.
Production of chain reaction by October 1, 1942.
Pilot plant for using reaction for copper production, October 1, 1943.
Copper in usable quantities by December 31, 1944.
His schedule was designed to show that plutonium might be produced in
time to influence the outcome of the war, the standard which Conant was
insisting upon aer Pearl Harbor even more vehemently than before.
But the
uranium-graphite work had not yet won even Compton’s full confidence.
If
graphite proved impractical and “copper production” had to wait for heavy
water (of which Harold Urey was urging the extraction at an existing plant
in Canada), Compton’s schedule would slip by “from 6 months to 18
months.” And that might be too late to make a difference.
For the next six months, Compton estimated, the pile studies at Columbia,
Princeton and Chicago would cost $590,000 for materials and $618,000 for
salaries and support.
“is figure seemed big to me,” he remembers
modestly, “accustomed as I was to work on research that needed not more
than a few thousand dollars per year.
”1548
He had met with Pegram and Fermi to prepare this part of his proposal
and concluded that when metallic uranium became available the project
should be concentrated at Columbia.
Over Christmas and through the first
weeks of January it fell to Herbert Anderson, the native son, to find a
building in the New York City area large enough to house a full-scale chain-
reacting pile.
Not to be outdone in the matter of informal codes, the
Columbia team had named that culmination “the egg-boiling
experiment.” 1549, 1550 Anderson stumped the wintry boroughs and turned up seven likely locations for boiling uranium eggs.
He proposed them to
Szilard on January 21; they included a Polo Grounds structure, an aircra
hangar on Long Island that belonged to Curtiss-Wright and the hangar
Goodyear used to house its blimps.
But as Compton reviewed the work of the several groups that had come
under his authority, bringing their leaders together in Chicago three times
during January, their disagreements and duplications made it obvious that
all the developmental work on the chain reaction and on plutonium
chemistry should be combined at one location.
Pegram offered Columbia.
ey considered Princeton and Berkeley and industrial laboratories in
Cleveland and Pittsburgh.
Compton offered Chicago.
No one wanted to
move.
e third meeting of the new year, on Saturday, January 24, Compton
conducted from his sickbed in one of the sparsely furnished spare bedrooms
on the third floor of his large University Avenue house: he had the flu.
Risking infection, Szilard attended, Ernest Lawrence, Luis Alvarez—
Lawrence and Alvarez sitting together on the next bed—and several other
men.
“Each was arguing the merits of his own location,” Compton writes,
“and every case was good.
I presented the case for Chicago.
”1551 He had
already won the support of his university’s administration.
“We will turn the
university inside out if necessary to help win this war,” its vice president had
sworn.
1552 at was Compton’s first argument: he knew the management
and had its support.
Second, more scientists were available to staff the
operation in the Midwest than on the coasts, where faculties and graduate
schools had been “completely drained” for other war work.
ird, Chicago
was conveniently and centrally located for travel to other sites.
Which convinced no one.
Szilard had forty tons of graphite on hand at
Columbia and a going concern.
e arguments continued.
Compton, who
was notoriously indecisive, suffered their brunt as long as he could bear it.
“Finally, wearied to the point of exhaustion but needing to make a firm
decision, I told them that Chicago would be [the project’s] location.” 1553
Lawrence scoffed.
“You’ll never get a chain reaction going here,” he baited
his fellow laureate.
“e whole tempo of the University of Chicago is too
slow.”
“We’ll have the chain reaction going here by the end of the year,” Compton
predicted.
“I’ll bet you a thousand dollars you won’t.”
“I’ll take you on that,” Compton says he answered, “and these men here
are the witnesses.”
“I’ll cut the stakes to a five-cent cigar,” Lawrence hedged.
“Agreed,” said Compton, who never smoked a cigar in his life.
Aer the crowd le, Compton shuffled wearily to his study and called
Fermi.
“He agreed at once to make the move to Chicago,” Compton writes.
Fermi may have agreed, but he found the decision burdensome.
He was
preparing further experiment.
His group was exactly the right size.
He
owned a pleasant house in a pleasant suburb.
He and Laura had buried a
cache of Nobel Prize money in a lead pipe under the concrete floor of their
basement coal bin against the possibility that as enemy aliens their assets
would be frozen.
Laura Fermi “had come to consider Leonia as our
permanent home,” she writes, “and loathed the idea of moving again.” 1554
She says her husband “was unhappy to move.
ey (I did not know who they
were) had decided to concentrate all that work (I did not know what it was)
in Chicago and to enlarge it greatly, Enrico grumbled.
It was the work he
had started at Columbia with a small group of physicists.
ere is much to
be said for a small group.
It can work quite efficiently.” 1555 But the country
was at war.
Fermi traveled back and forth by train until the end of April,
then camped in Chicago.
Laura dug up their buried treasure and followed at
the end of June.
To Szilard, the day aer the sickbed meeting—he had returned promptly
to New York—Compton sent a respectful telegram: THANK YOU FOR COMING
TO PRESENT ABLY COLUMBIA’S SITUATION.
NOW WE NEED YOUR HELP IN ORGANIZING
THE METALLURGICAL LABORATORY OF O.S.R.D.
IN CHICAGO.
CAN YOU ARRIVE HERE
WEDNESDAY MORNING WITH FERMI AND WIGNER...
TO DISCUSS DETAILS OF MOVING
AND ORGANIZATION.
1556 Unlike the Radiation Laboratory at MIT, the new
Metallurgical Laboratory hardly disguised its purpose in its name.
Who
would imagine its goal was the transmutation of the elements to make
baseball-sized explosive spheres of unearthly metal?
Before Fermi and his team moved to Illinois they built one more
exponential pile, this one loaded with cylindrical lumps of pressed uranium
oxide three inches long and three inches in diameter that weighed four
pounds each, some two thousand in all, set in blind holes drilled directly
into graphite.
1557 A new recruit, a handsome, dark-haired young
experimentalist named John Marshall, located a suitable press for the work
in a junkyard in Jersey City and set it up on the seventh floor of Pupin;
Walter Zinn designed stainless steel dies; the powdered oxide bound
together under pressure as medicinal tablets pressed from powder—aspirin,
for example—do.
Fermi was concerned to free the pile as completely as possible of moisture
to reduce neutron absorption.
He had canned the oxide before; now he
decided to can the entire nine-foot graphite cube.
“ere are no ready-made
cans of the needed size,” Laura Fermi says dryly, “so Enrico ordered one.” 1558
at, writes Albert Wattenberg, who joined the group in January, “required
soldering together many strips of sheet metal.
We were very fortunate in
getting a sheet metal worker who made excellent solder joints.
It was,
however, quite a challenge to deal with him, since he could neither read nor
speak English.
We communicated with pictures, and somehow he did the
job.
”1559 Laura Fermi picks up the story: “To insure proper assembly, they
marked each section with a little figure of a man: if the can were put together
as it should be, all men would stand on their feet, otherwise on their
heads.
”1560 e Columbia men preheated the oxide lumps to 480°F before
loading.
ey heated the contents of the room-sized can to the boiling point
of water and pumped down a partial vacuum.
eir heroic efforts reduced
the pile’s moisture to 0.03 percent.
With the same relatively impure uranium
and graphite they had used before but with these improved conditions and
arrangements they measured k at the end of April at an encouraging 0.918.
In Chicago in the meantime Samuel Allison had built a smaller seven-foot
exponential pile and measured k for his arrangement at 0.94.
e University
of Chicago had long ago sacrificed football to scholarship; Compton took
over the warren of disused rooms under the west stands of Stagg Field,
which was conveniently located immediately north of the main campus, and
made space available there to Allison.
Below solid masonry façades set with
Gothic windows and crenellated towers the stands concealed ball courts as
well as locker areas.
e unheated room Allison had used for his
experiment, sixty feet long, thirty feet wide, twenty-six feet high and sunk
half below street level, was a doubles squash court.
December 6, 1941, the day of the bomb program expansion, marked another
tidal event: Soviet forces under General Georgi Zhukov counterattacked
across a two-hundred-mile front against the German Army congealed in
snow and –35°F cold only thirty miles outside Moscow.
“Like the supreme
military genius who had trod this road a century before him,” Churchill
writes, evoking Napoleon Bonaparte, “Hitler now discovered what Russian
winter meant.” 1561 Zhukov’s hundred divisions came as a bitter surprise
—“well-fed, warmly clad and fresh Siberians,” a German general describes
them, “fully equipped for winter fighting” as the Wehrmacht troops were not
—and armies that had advanced half a thousand miles to push within sight
of the Kremlin stumbled back toward Germany nearly in rout.1562 For the
first time since Hitler began his conquests Blitzkrieg had failed.
“e winter
had fallen,” Churchill writes.
“e long war was certain.” 1563 Hitler relieved
his Army commander in chief of duty and appropriated that office to
himself.
By the end of March his casualties in the East, counting not the sick
but only the wounded, numbered nearly 1.2 million men.
It was clear in Berlin that the German economy had reached the limits of
its expansion.
Tradeoffs must follow.
e Minister of Munitions installed a
rule similar to the rule upon which Conant was insisting in the United
States, and the director of Reich military research promulgated it to the
physicists studying uranium: “e work...
is making demands which can
be justified in the current recruiting and raw materials crisis only if there is a
certainty of getting some benefit from it in the near future.
”1564 Aer
considering the question the War Office decided to reduce the priority of
uranium research by assigning most of it to the Ministry of Education under
Bernhard Rust, the scientifically illiterate SS Obergruppenführer and former
provincial schoolteacher who had refused to sanction Lise Meitner’s
emigration following the Anschluss.
e academic physicists were happy to
be out from under the Army but chagrined to be consigned to a backwater
ministry run by a party hack.
Rust delegated authority to the Reich Research
Council.
at organization was part of the Reich Bureau of Standards.
e
KWI physicists considered its physics section head, Abraham Esau,
incompetent.
In effect, the German uranium program had slipped in status
to the level of the old U.S.
Uranium Committee and now had its Briggs.
e Research Council decided to appeal directly to the highest levels of
the Reich for support.
It organized an elaborate presentation and invited
such dignitaries as Hermann Göring, Martin Bormann, Heinrich Himmler,
Navy commander in chief Admiral Erich Raeder, Field Marshal Wilhelm
Keitel and Albert Speer, Hitler’s admired patrician architect who was
Minister of Armaments and War Production.
Heisenberg, Hahn, Bothe,
Geiger, Clusius and Harteck were scheduled to speak at the February 26
meeting, Rust presiding, and an “Experimental Luncheon” would be served
offering entrées prepared from frozen foods basted with synthetic
shortening and bread made with soy flour.
1565
Unfortunately for the council’s ambitious plans, the secretary assigned to
send out invitations enclosed the wrong lecture program.
A secret scientific
conference under the auspices of Army Ordnance had been scheduled at the
Kaiser Wilhelm Society’s Harnack House for the same day.
Its program listed
twenty-five highly technical scientific papers.
at was the program the
leaders of the Reich mistakenly received.
Himmler regretted: he would be
away from Berlin that day.
Keitel was “too busy at the moment.” 1566 Raeder
would send a representative.
None of the leaders chose to attend.
What Heisenberg had to say might have surprised them.
He emphasized
atomic energy for power but also discussed military uses.
“Pure uranium-
235 is thus seen to be an explosive of quite unimaginable force,” he told his
staff-level auditors.
“e Americans seem to be pursuing this line of research
with particular urgency.” Inside a uranium reactor “a new element is created
[i.e., plutonium]...
which is in all probability as explosive as pure uranium-
235, with the same colossal force.” 1567 At the same time at Harnack House,
where Leo Szilard once lodged, bags packed, Army Ordnance was learning
that “it would suffice to bring together two lumps of this explosive, weighing
a total oen to a hundred kilograms, for it to detonate.” 1568
Basic knowledge of one direct route to an atomic bomb—via plutonium—
was at hand.
What was lacking was money and materials.
e February 26
meeting won over at least the Minister of Education.
“e first time large
funds were available in Germany,” Heisenberg recalled at the end of the war,
“was in the spring of 1942, aer that meeting with Rust, when we convinced
him that we had absolutely definite proof that it could be done.” 1569
Heisenberg’s “large” is relative to the modest funds that had been available
before, however.
Not Bernhard Rust but Albert Speer needed to be
convinced of the military promise of atomic energy to swell the scale of
funding anywhere near the billions of reichsmarks that production of even
ten kilograms of U235 or plutonium would require.
Speer did not recall the February 26 invitation aer the war.
Atomic
energy first came to his attention, he writes in his memoirs, at one of his
regular private luncheons with General Friedrich Fromm, the commander
of the Home Army.
“In the course of one of these meetings, at the end of
April 1942, [Fromm] remarked that our only chance of winning the war lay
in developing a weapon with totally new effects.
He said he had contacts
with a group of scientists who were on the track of a weapon which could
annihilate whole cities....
Fromm proposed that we pay a joint visit to these
men.” Speer also heard that spring from the president of the Kaiser Wilhelm
Society, who complained of lack of support for uranium research.
“On May
6, 1942, I discussed this situation with Hitler and proposed that Göring be
placed at the head of the Reich Research Council—thus emphasizing its
importance.” 1570
at shi to the obese Reichsmarshal who commanded the Luwaffe and
whom Hitler had designated to be his successor carried only symbolic
promotion.
More crucial was a June 4 conference at Harnack House that
Speer, Fromm, automobile and tank designer Ferdinand Porsche and other
military and industrial leaders attended.
In February Heisenberg had
devoted most of his lecture to nuclear power.
is time he emphasized
military prospects.
e secretary of the Kaiser Wilhelm Society was
surprised: “e word ‘bomb’ which was used at this conference was news
not only to me but for many others present, as I could see from their
reaction.
”1571 It was not news to Speer.
When Heisenberg took questions
from the floor, one of Speer’s deputies asked how large a bomb capable of
destroying a city would have to be.
Heisenberg cupped his hands as Fermi
had done sighting down Manhattan Island from Pupin Hall.
“As large as a
pineapple,” he said.
1572
Aer the briefings Speer questioned Heisenberg directly.
How could
nuclear physics be applied to the manufacture of atomic bombs?
e
German laureate seems to have shied from committing himself.
“His answer
was by no means encouraging,” Speer remembers.
“He declared, to be sure,
that the scientific solution had already been found....
But the technical
prerequisites for production would take years to develop, two years at the
earliest, even provided that the program was given maximum support.” ey
were crippled by an absence of cyclotrons, Heisenberg said.
Speer offered to
build cyclotrons “as large as or larger than those in the United States.”
Heisenberg demurred that German physicists lacked experience building
large cyclotrons and would have to start small.
Speer “urged the scientists to
inform me of the measures, the sums of money and the materials they would
need to further nuclear research.” A few weeks later they did, but their
requests looked picayune to a Reichsminister accustomed to dealing in
billions of marks.
ey requested “an appropriation of several hundred
thousand marks and some small amounts of steel, nickel, and other priority
metals....
Rather put out by these modest requests in a matter of such
crucial importance, I suggested that they take one or two million marks and
correspondingly larger quantities of materials.
But apparently more could
not be utilized for the present, and in any case I had been given the
impression that the atom bomb could no longer have any bearing on the
course of the war.
”1573
Speer saw Hitler regularly and duly reported the findings of the June
conferences:
Hitler had sometimes spoken to me about the possibility of an atom bomb, but the idea quite
obviously strained his intellectual capacity.
He was also unable to grasp the revolutionary nature of
nuclear physics.1574 In the twenty-two hundred recorded points of my conferences with Hitler, nuclear fission comes up only once, and then is mentioned with extreme brevity.
Hitler did
sometimes comment on its prospects, but what I told him of my conferences with the physicists
confirmed his view that there was not much profit in the matter.
Actually, Professor Heisenberg had not given any final answer to my question whether a successful nuclear fission could be kept
under control with absolute certainty or might continue as a chain reaction.
Hitler was plainly not
delighted with the possibility that the earth under his rule might be transformed into a glowing
star.
Occasionally, however, he joked that the scientists in their unworldly urge to lay bare all the
secrets under heaven might some day set the globe on fire.
But undoubtedly a good deal of time
would pass before that came about, Hitler said; he would certainly not live to see it.
Following that, according to Speer, “on the suggestion of the nuclear
physicists we scuttled the project to develop an atom bomb...
aer I had
again queried them about deadlines and been told that we could not count
on anything for three or four years.” Work on what Speer calls “an energy-
producing uranium motor for propelling machinery”—the heavy-water pile
—would continue.1575 “In the upshot,” Heisenberg wrote in Nature in 1947,
summarizing the war years, German physicists “were spared the decision as
to whether or not they should aim at producing atomic bombs.
1576 e
circumstances shaping policy in the critical year of 1942 guided their work
automatically toward the problem of the utilization of nuclear energy in
prime movers.” But the Allies had not yet been informed.
* * *
“We may be engaged in a race toward realization,” Vannevar Bush wrote
Franklin Roosevelt on March 9, 1942; “but, if so, I have no indication of the
status of the enemy program, and have taken no definite steps toward
finding out.
”1577, 1578 Why Bush was not more curious remains a mystery.
Conant, Lawrence and Compton, not to mention the emigrés, fretted
continually about the possibility of a German bomb.
It was their primary
reason for urging an American bomb.
It was not Bush’s or Roosevelt’s—to
them the bomb offered offensive advantage first of all—but the two leaders
were alert to the German danger and surprisingly indifferent to assessing it.
e report that accompanied Bush’s letter stated that five to ten pounds of
“active material” would be “fairly certain” to explode with a force equivalent
to 2,000 tons of TNT, up from 600 tons in the third National Academy of
Sciences report of the previous November 6.
It recommended building a
centrifuge plant at a cost of $20 million that could produce enough U235 for
one bomb a month and estimated that such a plant could be completed by
December 1943.
A gaseous diffusion plant, its cost unspecified, might
deliver by the end of 1944.
An electromagnetic separation plant—Ernest
Lawrence’s project—won the most attention in the report: it might “offer a
short-cut,” wrote Bush, and deliver “fully practicable quantities of material
by the summer of 1943, with a time saving of perhaps six months or even
more.” In summary, “present opinion indicates that successful use is
possible, and that this would be very important and might be determining in
the war effort.
It is also true that if the enemy arrived at results first it would
be an exceedingly serious matter.
e best estimate indicates completion in
1944, if every effort is made to expedite.”
Roosevelt responded two days later: “I think the whole thing should be
pushed not only in regard to development, but also with due regard to time.
is is very much of the essence.
”1579 Time, not money, was becoming the
limiting factor in atomic bomb development.
A meeting on May 23 brought all the program leaders together with
Conant to decide which of several methods of making a bomb should be
moved on to the pilot-plant and industrial engineering stages.
e
centrifuge, gaseous barrier diffusion, electromagnetic and graphite or heavy-
water plutonium-pile approaches all looked equally promising.
Given
wartime scarcities and budget priorities, which should be advanced?
Conant
used an arms-race argument to identify the point of decision:
While all five methods now appear to be about equally promising, clearly the time of production of
a dozen bombs by the five routes will certainly not be the same but might vary by six months or a
year because of unforeseen delays.
erefore, if one discards one or two or three of the methods
now, one may be betting on the slower horse unconsciously.
To my mind the decision as to how
“all out” the effort should be might well turn on the military appraisal of what would occur if either
side had a dozen or two bombs before the other.1580
To that point Conant reviewed the evidence for a German bomb program,
including new indications of espionage activity: information from the
British that the Germans had a ton of heavy water; Peter Debye’s report
when he arrived in the United States eighteen months earlier that his
colleagues at the KWI were hard at work; and “the recently intercepted
instruction to their agents in this country [that] shows they are interested in
what we are doing.
”1581 Conant thought this last evidence the best.
“If they
are hard at work, they cannot be far behind since they started in 1939 with
the same initial facts as the British and ourselves.
ere are still plenty of
competent scientists le in Germany.
ey may be ahead of us by as much as
a year, but hardly more.”
If time, not money, was the crucial issue—in Conant’s words, “if the
possession of the new weapon in sufficient quantities would be a
determining factor in the war”—then “three months’ delay might be fatal.” It
followed that all five methods should be pushed at once, even though “to
embark on this Napoleonic approach to the problem would require the
commitment of perhaps $500,000,000 and quite a mess of machinery.” 1582
* * *
Glenn Seaborg arrived in Chicago aboard the streamliner City of San
Francisco at 9:30 A.M.
Sunday, April 19, 1942, his thirtieth birthday.
As he
le the station he noticed first that Chicago was cold compared to Berkeley
—forty degrees that spring morning.
1583 en headlines at a newsstand
caught him up on the developing Pacific war: the Japanese reported
American aircra had bombed Tokyo and three other Honshu cities, a
surprise attack that neither Southwest Pacific commander General Douglas
MacArthur nor Washington acknowledged (it was Jimmy Doolittle’s morale
raid of sixteen B-25 bombers launched one-way across Japan to landing
fields in China from the U.S.
aircra carrier Hornet).
“is day...
marks a
transition point in my life,” Seaborg writes in his carefully documented
diary-style memoir, “for tomorrow I will take on the added responsibility of
the 94 chemistry group at the Metallurgical Laboratory on the University of
Chicago campus, the central component of the Metallurgical Project.
”1584
Transmuting U238 to plutonium in a chain-reacting pile was one thing,
extracting the plutonium from the uranium quite another.
e massive
production piles that Compton’s people were already beginning to plan
would create the new element at a maximum concentration in the uranium
of about 250 parts per million—a volume, uniformly dispersed through each
two tons of mingled uranium and highly radioactive fission products, equal
to the volume of one U.S.
dime.
Seaborg’s work was somehow to pull that
dime’s worth out.1585
He had made a good beginning at Berkeley, exploring plutonium’s unusual
chemistry.
Oxidizing agents are chemicals that strip electrons from the outer
shells of atoms.
Reducing agents conversely add electrons to the outer shells
of atoms.
Plutonium, it seemed, precipitated differently when it was treated
with oxidizing agents than when it was treated with reducing agents.
In a +4
oxidation state, the Berkeley team had found, the manmade element could
be precipitated out of solution using a rare-earth compound such as
lanthanum fluoride as a carrier.
Oxidize the same plutonium to a +6
oxidation state and the precipitation no longer worked; the carrier
crystallized but the plutonium remained behind in solution.
at gave
Seaborg a basic approach to extraction:
We conceived the principle of the oxidation-reduction cycle....
is principle applied to any
process involving the use of a substance which carried plutonium in one of its oxidation states but
not in another....
For example, a carrier could be used to carry plutonium in one oxidation state
and thus to separate it from uranium and the fission products.
en the carrier and the plutonium
[now solid crystals] could be dissolved, the oxidation state of the plutonium changed, and the
carrier reprecipitated, leaving the plutonium in solution.
e oxidation state of the plutonium
could again be changed and the cycles repeated.
With this type of procedure, only a contaminating
element having a chemistry nearly identical with the plutonium itself would fail to separate if a
large number of oxidation-reduction cycles were employed.
1586
A two-day chemistry conference began on Wednesday, April 23, with
Eugene Wigner, Harold Urey, Princeton theoretician John A.
Wheeler and a
number of chemists already assigned to the Met Lab on hand.
e scientists
discussed seven possible ways to extract plutonium from irradiated
uranium.
ey favored four that seemed particularly adaptable to remote
control, not including precipitation.
1587 Seaborg, the new man, disagreed: “I,
however, expressed confidence in the use of precipitation.” ey would
nevertheless investigate all seven methods proposed.
at would require the
full-time work of forty men.
One of Seaborg’s jobs for months to come was
recruiting.
It worried him: “Sometimes I feel a little apprehensive about
inviting...
people to give up their secure university positions and come to
work at the Met Lab.
ey must gamble on the future of their careers, and
how long they will be diverted from them nobody knows.” But if no one
knew how long the work would last, most of them came to believe it
transcendently important: “ere is a statement of rather common currency
around here and Berkeley that goes something like this: ‘No matter what you
do with the rest of your life, nothing will be as important to the future of the
World as your work on this Project right now.’ ”1588
So far Seaborg had studied plutonium by following the characteristic
radioactivity of minute amounts vastly diluted in carrier, the same tracer
chemistry that Hahn, Fermi and the Joliot-Curies had used.
Chemical
reactions oen proceed differently at different dilutions, however.
To prove
that an extraction process would work at industrial scale, Seaborg knew he
would have to demonstrate it at industrial-scale concentrations.
In
peacetime he might have waited until a pile large enough to transmute at
least gram quantities of plutonium was built and operating.
at normal
procedure was a luxury the bomb program could not afford.
Seaborg looked instead for a way to make more plutonium without a pile
and a way to work with concentrated solutions of the little he might make.
e resources of the OSRD came to his aid in the first instance, his own
imagination and ingenuity in the second.
He commandeered the 45-inch
cyclotron at Washington University in St.
Louis, where Compton had once
hidden out, and arranged to have 300-pound batches of uranium nitrate
hexahydrate bombarded heroically with neutrons for weeks and months at a
time.
So long and intense a bombardment would give him microgram
quantities of plutonium—several hundred millionths of a gram, amounts
hardly visible to the naked eye.
He then somehow had to devise techniques
for mixing, measuring and analyzing them.
Visiting New York earlier that month to deliver a lecture, Seaborg had
sought out a quaint soul named Anton Alexander Benedetti-Pichler, a
professor at Queens College in Flushing who had pioneered
ultramicrochemistry, a technology for manipulating extremely small
quantities of chemicals.
Benedetti-Pichler had briefed Seaborg thoroughly
and promised to send a list of essential equipment.
Seaborg hired one of
Benedetti-Pichler’s former students and together the two men planned an
ultramicrochemistry laboratory.
“We looked for a good spot that would be
vibration-free for the microbalances and settled on Room 405 (a former
darkroom) in Jones Laboratory which has a concrete bench.” 1589 e former
darkroom, hardly six feet by nine, was scaled to the work.
Another specialist in ultramicrochemistry, Paul Kirk, taught at Berkeley.
Seaborg hired a recent Ph.D.
whom Kirk had trained, Burris Cunningham,
and a graduate student, Louis B.
Werner.
“I always thought I was tall,” the
chemistry laureate comments, but Werner at six feet seven topped him by
four inches, “a tight fit” in the small laboratory.
1590
With the special tools of ultramicrochemistry the young chemists could
work on undiluted quantities of chemicals as slight as tenths of a microgram
(a dime weighs about 2.5 grams— 2,500,000 micrograms).
ey would
manage their manipulations on the mechanical stage of a binocular
stereoscopic microscope adjusted to 30-power magnification.
Fine glass
capillary straws substituted for test tubes and beakers; pipettes filled
automatically by capillary attraction; small hypodermic syringes mounted
on micromanipulators injected and removed reagents from centrifuge
microcones; miniature centrifuges separated precipitated solids from
liquids.
e first balance the chemists used consisted of a single quartz fiber
fixed at one end like a fishing pole stuck into a riverbank inside a glass
housing that protected it from the least breath of air.
To weigh their
Lilliputian quantities of material they hung a weighing pan, made of a
snippet of platinum foil that was itself almost too small to see, to the free
end of the quartz fiber and measured how much the fiber bent, a deflection
which was calibrated against standard weights.
A more rugged balance
developed at Berkeley had double pans suspended from opposite ends of a
quartz-fiber beam strung with microscopic struts.
“It was said,” notes
Seaborg, “that ‘invisible material was being weighed with an invisible
balance.’ ” 1591
In addition to his new Met Lab responsibilities Seaborg still coordinated
basic scientific studies of uranium and plutonium at Berkeley.
At the
beginning of June he traveled to California to meet with “the fellows on the
third floor of Gilman Hall” and to marry Ernest Lawrence’s secretary.1592 On
June 6, returning to Chicago through Los Angeles, where Seaborg’s parents
lived, bride and groom prepared for a quick Nevada wedding.
ey got off
the train in Caliente, Nevada, stored their bags with the telegraph operator
at the station and asked directions to the city hall.
“But to our vexation we
learned there is no city hall here and in order to get our marriage license we
would have to go to the county seat, a town called Pioche, some 25 miles to
the north.” 1593 Providentially the deputy sheriff who served as Caliente’s
travel adviser and all-around troubleshooter turned out to be a June
graduate of the Berkeley chemistry department.
He arranged for the
professor and his bride, Helen Griggs, to ride to Pioche in a mail truck.
“Our
witnesses were a janitor whom we recruited and [a] friendly clerk.
We
returned to Caliente on the mail truck’s 4:30 run and checked into the local
hotel here for our overnight stay.” 1594
Arriving in Chicago on June 9 Seaborg delivered his wife to the apartment
he had rented before he le for California and proceeded immediately to his
office.
His mail informed him that Edward Teller was joining the Chicago
project to work in the theoretical group under Eugene Wigner.
Two days later Robert Oppenheimer turned up in Chicago and dropped
by to see Seaborg; they were old friends but “it was more than just a social
call.” 1595 Gregory Breit, the Wisconsin-based theoretician on the Uranium
Committee who had been responsible for fast-neutron studies, had resigned
from the bomb project in protest over what he felt were serious violations of
security.
“I do not believe that secrecy conditions are satisfactory in Dr.
Compton’s project,” he had written Briggs on May 18.
His litany of examples
approached paranoia.
“Within the Chicago project there are several
individuals strongly opposed to secrecy.
One of the men, for example,
coaxed my secretary there to give him some official reports out of my safe
while I was away on a trip....
e same individual talks quite freely within
the group....
I have heard him advocate the principle that all parts of the
work are so closely interrelated that it is desirable to discuss them as a
whole.
”1596 e dangerous individual Breit chose not to name was Enrico
Fermi, pushing to make the chain reaction go.
Compton had appointed
Oppenheimer to replace Breit and Oppenheimer was visiting Seaborg for a
briefing on the fast-neutron studies Seaborg was coordinating at Berkeley.
Studying fast-neutron reactions, Seaborg notes, was “a prerequisite to the
design of an atomic bomb.” 1597 Oppenheimer had found a place for himself
on the ground floor.
e Washington University cyclotron crew moved the first 300 pounds of
uranium nitrate hexahydrate into position around the machine’s beryllium
target on June 17.
e UNH was scheduled for a month’s bombardment,
50,000 microampere-hours.
ough the chain reaction had not yet been
proved and no one had yet seen plutonium, the various Met Lab councils of
which Seaborg was a member had already begun debating the design and
location of the big 250,000-kilowatt production piles that would create
pounds of the strange metal if all went well.
Fermi thought plutonium
production needed an area a mile wide and two miles long for safety.
Compton proposed building piles of increasing power to work up to full-
scale production and was considering alternative sites in the Lake Michigan
Dunes area and in the Tennessee Valley.
A question that would eventually encompass many other issues, some of
them profound, was how to cool the big piles.
Early in the organization of
the Met Lab Compton had appointed an engineering council to consider
such questions; besides an engineer and an industrial chemist the council
included Samuel Allison, Fermi, Seaborg, Szilard and John A.
Wheeler
among its membership.
By late June its discussions had progressed to the
point of tentative commitment.
Helium was one prospective coolant, to be
circulated at high pressure inside a sealed steel shell; its zero cross section
for neutron absorption was only one of its several advantages.
Water was
another coolant possibility, the heat-exchange medium most familiar to
engineers but corrosive to uranium.
An exotic third was bismuth, a metal
with a low 520°F melting point that serves as a watchful solid in fuses and
automatic fire alarms.
Melted to a liquid it would transfer heat far more
efficiently than helium or water.
Szilard championed a liquid-bismuth
cooling system in part because the metal could be circulated through the
pile with a scaled-up version of the magnetic pump he and Albert Einstein
had invented for refrigerators, a mechanism that had no moving parts to
leak or fail.
e engineering council ruled out liquid cooling, Seaborg writes, “because
of potential chemical action, danger of leaks and difficulty in transferring
heat from oxide....
ere was general agreement to use helium.
”1598 Eugene
Wigner had not been invited onto the council despite his interest in its
problems and his thorough knowledge of chemical engineering.
Wigner
strongly favored water cooling, says Szilard, because “a water cooled system
could be built in a much shorter time.
”1599 Seaborg corroborates Wigner’s
continuing desperate concern about a German bomb:
Compton repeated a conversation that ensued between him and Wigner on a possible schedule of
the Germans.
Like us, they have had three years since the discovery of fission to prepare a bomb.
Assuming they know about [plutonium], they could run a heavy water pile for two months at
100,000 kw and produce six kilograms of it; thus it would be possible for them to have six bombs
by the end of this year [1942].
On the other hand, we don’t plan to have bombs in production until
the first part of 1944.
1600
Compton encouraged Wigner’s group to design a water-cooled pile but
ordered up detailed engineering studies only of a system using helium.
e basic issue behind the technical dispute was control, which Szilard at
least understood they were systematically signing away to the U.S.
government.
A meeting on June 27 intensified the conflict.
Bush’s latest
status report to Roosevelt on June 17 had proposed dividing the work of
development and ultimate production between the OSRD and the U.S.
Army Corps of Engineers, bringing in the Army to build and run the
factories as Bush had planned to do all along.
Roosevelt initialed Bush’s
cover letter “OK.
FDR.” and returned it immediately.
e same day the Chief
of Engineers ordered Colonel James C.
Marshall of the Syracuse Engineer
District, a 1918 West Point graduate with experience building air bases, to
report to Washington for duty.
Marshall selected the Boston construction
engineering corporation of Stone & Webster as principal contractor for the
bomb project.
To report the reorganization Compton called the June 27
meeting of his group leaders and planning board.
Allison, Fermi, Seaborg,
Szilard, Teller, Wigner and Zinn attended, among others.1601
“Compton opened the meeting with a pep talk,” Seaborg remembers,
“asking us to go ahead with all vigor possible.
He said our aim the past half-
year has been to investigate the possibilities of producing an atomic bomb—
now we have the responsibility to proceed from the military point of view
on the assumption it can be done and we can assume we have a project for
the entire duration of the war.” Compton was stealthily working his way to
the new arrangements.
He emphasized the program’s secrecy.
“Only about
six men in the U.S.
Army are permitted to know what is going on,” Seaborg
paraphrases him; those privileged few included Secretary of War Henry L.
Stimson—heady company for men who had only recently been graduate
students or obscure academics—and “two construction experts,” generals
whom Compton then named.
He described the responsibilities of the
“construction experts” and finally broke the news: “It is hoped to have a
contractor assume responsibility for the production plant.” A contractor
already had.
Compton’s announcement had the effect he seems to have feared, Seaborg
goes on: “A number of the people present expressed great concern about
working for an industrial contractor because of their fear that this would not
be a compatible environment in which to work.” ey would not have to
work for such a contractor, though they would obviously have to work with
one, but to make the reorganization palatable Compton hinted at worse that
might be yet to come: “ere was considerable talk about our being
absorbed into the Army [i.e., commissioned as officers] and what the
advantages and disadvantages might be.
ere were vigorous objections
from most of the people present.”
e problem would fester all summer and burst through again in the fall.
Szilard would define it precisely in a memorandum: “Stated in abstract form,
the trouble at Chicago arises out of the fact that the work is organized along
somewhat authoritative [sic: authoritarian] rather than democratic lines.” 1602
e visionary Hungarian physicist did not believe science could function by
fiat.
“In 1939,” he had already written Vannevar Bush passionately in late
May, before the cooling-system and contractor debates, “the Government of
the United States was given a unique opportunity by Providence; this
opportunity was lost.
Nobody can tell now whether we shall be ready before
German bombs wipe out American cities.
Such scanty information as we
have about work in Germany is not reassuring and all one can say with
certainty is that we could move at least twice as fast if our difficulties were
eliminated.” 1603
ree hundred pounds of irradiated UNH—yellowish crystals like rock
salt—arrived from St.
Louis by truck on July 27, a Monday:
e UNH was surrounded by a layer of lead bricks.
[Truman] Kohman and [Elwin H.] Covey were
detailed to unload the shipment and carry it up to our lab on the fourth floor for extraction of the
94239.
e UNH crystals came packaged in small boxes of various sizes, made to fit into the various
niches around the cyclotron target.
Some of the boxes were made of masonite, but most of them
were of quarter inch plywood.
Unfortunately, some of the seams and edges had cracked open,
allowing crystals of hot [i.e., radioactive] UNH to creep out.
We could not get hold of any
instrument to measure the radioactivity.
I told Kohman and Covey their best protection would be
to wear rubber gloves and a lab coat....
Although they struggled for half the day to get all the
boxes and lead bricks upstairs into the storage area, I think they were conscientious and kept their
radiation exposure to a minimum.
1604
While Seaborg’s high-spirited crew of young chemists began attempting to
extract plutonium 239 from the bulky St.
Louis UNH, wrestling with
carboys of ether and heavy three-liter separatory funnels held at arm’s length
from behind lead shields, Cunningham and Werner in narrow Room 405
started toward isolating plutonium as a pure compound.
ey first measured
out a 15-milliliter solution of UNH irradiated earlier that summer in the 60-
inch Berkeley cyclotron.
ey assumed their solution then contained about
one microgram of plutonium 239.
( Pu 239, that is: Seaborg had chosen the
abbreviation Pu rather than P1 partly to avoid confusion with platinum, Pt,
but also “facetiously,” he says, “to create attention”—P.U.
the old slang for
putrid, something that raises a stink.
1605) Working with their
ultramicrochemical
equipment—slow,
tedious
operations
via
micromanipulator gearing down large motions to microscopically small—
on August 15, a Saturday, they mixed the rare earths cerium and lanthanum
into their solution as carriers, partially evaporated it and precipitated the
carriers and the Pu as fluorides.
ey dissolved the precipitated crystals in a
few drops of sulfuric acid and evaporated the resulting solution to a volume
of about one milliliter, a thousandth of a liter, some twenty drops.
ey
checked the larger volume of solution le behind and found essentially no
alpha activity, evidence that the alpha-active Pu had crystallized out with the
rare earths.
at was a day’s work and they stored the precipitate solution
carefully for Monday and went home.
On Monday, August 17, Cunningham and Werner began by oxidizing
their small volume of precipitate to change the oxidation state of its Pu.
ey
repeated the oxidation and reduction cycles on the solution several times.
At
the end of the day their quartz centrifuge microcone contained a minute
drop of liquid that radiated some 57,000 alpha particles per minute.
ey set
it in a steam bath to concentrate it.
On Tuesday the two men transferred the concentrated solution to a
shallow platinum dish to prepare to concentrate it further.
It began creeping
over the sides.
Rather than lose it they moved it quickly to the only larger
dish at hand, which was contaminated with lanthanum.
eir misjudgment
of volume condemned them to another day of repurifying.
Upstairs in the
attic and on the roof Seaborg’s bulk UNH crew stirred large-volume
extractions of ether and water.
It was hot and heavy work.
Room 405 had a purified concentrate again to process Wednesday
morning.
It was still contaminated with a potassium compound and with
silver.
Cunningham and Werner diluted it and precipitated out the silver as a
chloride.
ey added five micrograms of lanthanum and precipitated out the
Pu along with the lanthanum carrier.
ey dissolved the precipitate,
oxidized it once more to change over the Pu and precipitated out the
lanthanum.
at le pure plutonium in solution, one more morning’s work
to bring down.
Of ursday, August 20, 1942, Seaborg writes:
Perhaps today was the most exciting and thrilling day I have experienced since coming to the Met Lab.
Our microchemists isolated pure element 94 for the first time!
is morning Cunningham
and Werner set about fuming...
yesterday’s 94 solution containing about one microgram of 94239,
added hydrofluoric acid whereupon the reduced 94 precipitated as the fluoride...
free of carrier
material....
1606
is precipitate of 94, which was viewed under the microscope and which was also visible to the
naked eye, did not differ visibly from the rare-earth fluorides....
It is the first time that element 94...
has been beheld by the eye of man.
By aernoon “a holiday spirit prevailed in our group.” Aer several hours’
exposure to air “the precipitated [plutonium] had taken on a pinkish
hue.” 1607 Someone photographed Cunningham and Werner at their crowded
bench in the narrow, tile-walled room—trim, strong-jawed young men
looking weary.
e crew upstairs that muscled carboys and lead bricks
shuffled in like clumsy shepherds to peer through the microscope at the
miracle of the tiny pinkish speck.
* * *
In the summer of 1942 Robert Oppenheimer gathered together at Berkeley a
small group of theoretical physicists he was amused to call the
“luminaries.” 1608 eir job was to throw light on the actual design of an
atomic bomb.
Hans Bethe, now thirty-six and a highly respected professor of physics at
Cornell, had resisted joining the bomb project because he doubted the
weapon’s feasibility.
“I considered...
an atomic bomb so remote,” Bethe told
a biographer aer the war, “that I completely refused to have anything to do
with it....
Separating isotopes of such a heavy element [as uranium] was
clearly a very difficult thing to do, and I thought we would never succeed in
any practical way.” 1609 But Bethe may well have headed the list of luminaries
Oppenheimer wanted to attract.
By 1942 the Cornell physicist had
established himself as a theoretician of the first rank.
His most outstanding
contribution, for which he would receive the 1967 Nobel Prize in Physics,
was to elucidate the production of energy in stars, identifying a cycle of
thermonuclear reactions involving hydrogen, nitrogen and oxygen that is
catalyzed by carbon and culminates in the creation of helium.
Among other
important work during the 1930s Bethe had been principal author of three
lengthy review articles on nuclear physics, the first comprehensive survey of
the field.
Bound together, the three authoritative studies came to be called
“Bethe’s Bible.”
He had wanted to help oppose Nazism.
“Aer the fall of France,” he says,
“I was desperate to do something—to make some contribution to the war
effort.” 1610 First he developed a basic theory of armor penetration.
On the
recommendation of eodor von Kármán, whom he consulted at Caltech,
he and Edward Teller in 1940 extended and clarified shock-wave theory.
In
1942 he joined the Radiation Laboratory at MIT to work on radar.
at was
where Oppenheimer found him.
Oppenheimer cleared his plan with Lee A.
DuBridge, the director of the
Rad Lab, then set a senior American theoretician, John H.
Van Vleck,
professor of physics at Harvard, to snare Bethe for the Berkeley summer
study.
“e essential point,” he counseled Van Vleck, “is to enlist Bethe’s
interest, to impress on him the magnitude of the job we have to do...
and to
try to convince him, too, that our present plans...
are the appropriate
machinery.” Oppenheimer felt the weight of the work.
“Every time I think
about our problem a new headache appears,” he told the Harvard professor.
“We shall certainly have our hands full.” 1611 Van Vleck arranged to meet
Bethe conspiratorially in Harvard Yard and succeeded in convincing him he
was needed.
e prearranged signal to Oppenheimer was a Western Union
Kiddygram, an inexpensive standardized telegram with a message like
“Brush your teeth.” 1612
Oppenheimer also invited Edward Teller.
In 1939 Bethe had married Rose
Ewald, the attractive and intelligent daughter of his Stuttgart physics
professor Paul Ewald; Edward and Mici Teller, “our best friends in this
country,” had attended the New Rochelle wedding.
1613 Setting out for
Berkeley in early July 1942, the Bethes stopped over in Chicago to pick up
the Tellers.
1614 Teller showed Bethe Fermi’s latest exponential pile.
“He had a
setup under one of the stands in Stagg Field,” Bethe remembers—“in a
squash court—with tremendous stacks of graphite.” A chain reaction that
made plutonium would bypass the problem of isotope separation.
“I then,”
says Bethe, “became convinced that the atomic-bomb project was real, and
that it would probably work.
”1615
e other luminaries enlisted for the summer study were Van Vleck, the
Swiss-born Stanford theoretician Felix Bloch, Oppenheimer’s former student
and close collaborator Robert Serber, a young Indiana theoretician named
Emil Konopinski and two postdoctoral assistants.
Konopinski and Teller had
arrived at the Met Lab at about the same time earlier that year.
“We were
newcomers in the bustling laboratory,” Teller writes in a memoir, “and for a
few days we were given no specific jobs.” Teller proposed that he and
Konopinski review his calculations that seemed to prove the impossibility of
using an atomic bomb to ignite a thermonuclear reaction in deuterium:
Konopinski agreed, and we tackled the job of writing a report to show, once and for all, that it
could not be done....
But the more we worked on our report, the more obvious it became that the
roadblocks which I had erected for Fermi’s idea were not so high aer all.
We hurdled them one by
one, and concluded that heavy hydrogen actually could be ignited by an atomic bomb to produce
an explosion of tremendous magnitude.
By the time we were on our way to California...
we even
thought we knew precisely how to do it.
1616
at was not news Edward Teller was likely to hide under a bushel,
whatever Oppenheimer’s official agenda.
Bethe was ushered into the glare as
the streamliner clicked west: “We had a compartment on the train to
California, so we could talk freely....
Teller told me that the fission bomb
was all well and good and, essentially, was now a sure thing.
In reality, the
work had hardly begun.
Teller likes to jump to conclusions.
He said that
what we really should think about was the possibility of igniting deuterium
by a fission weapon—the hydrogen bomb.
”1617
At Berkeley the luminaries began meeting in Oppenheimer’s office, “in the
northwest corner of the fourth floor of old LeConte [Hall],” an older
colleague remembers.
“Like all those rooms, it had French doors opening
out onto a balcony, to which there was easy access from the roof.
Accordingly a very strong wire netting was fastened securely over his
balcony.” Only Oppenheimer had a key.
“If a fire had ever started...
in
Oppenheimer’s absence, it would have been tragic.” 1618 But the fires that
summer were still only theoretical.
e theoreticians let Teller’s bomb distract them.
It was new, important
and spectacular and they were men with a compulsion to know.
“e theory
of the fission bomb was well taken care of by Serber and two of his young
people,” Bethe explains.
ey “seemed to have it well under control so we felt
we didn’t need to do much.” 1619 e essentials of fast-neutron fission were
firm—it needed experiment more than theory.
e senior men turned their
collective brilliance to fusion.
ey had not yet bothered to name generic
bombs of uranium and plutonium.
But from the pre-anthropic darkness
where ideas abide in nonexistence until minds imagine them into the light,
the new bomb emerged already chased with the technocratic euphemism of
art deco slang: the Super, they named it.
Rose Bethe, who was then twenty-four, understood instantly.
“My wife
knew vaguely what we were talking about,” says Bethe, “and on a walk in the
mountains in Yosemite National Park she asked me to consider carefully
whether I really wanted to continue to work on this.
Finally, I decided to do
it.” e Super “was a terrible thing.” But the fission bomb had to come first in
any case and “the Germans were presumably doing it.” 1620
Teller had examined two thermonuclear reactions that fuse deuterium
nuclei to heavier forms and simultaneously release binding energy.
Both
required that the deuterium nuclei be hot enough when they collided—
energetic enough, violently enough in motion—to overcome the nuclear
electrical barrier that usually repels them.
e minimum necessary energy
was thought at the time to come to about 35,000 electron volts, which
corresponds to a temperature of about 400 million degrees.
1621 Given that
temperature—and on earth only an atomic bomb might give it—both
thermonuclear reactions should occur with equal probability.
In the first,
two deuterium nuclei collide and fuse to helium 3 with the ejection of a
neutron and the release of 3.2 million electron volts of energy.
In the second
the same sort of collision produces tritium—hydrogen 3, an isotope of
hydrogen with a nucleus of one proton and two neutrons that does not
occur naturally on earth—with the ejection of a proton and the release of 4.0
MeV of energy.
e D + D reactions’ release of 3.6 MeV was slightly less by mass than
fission’s net of 170 MeV.
But fusion was essentially a thermal reaction, not
inherently different in its kindling from an ordinary fire; it required no
critical mass and was therefore potentially unlimited.
Once ignited, its
extent depended primarily on the volume of fuel—deuterium—its designers
supplied.
And deuterium, Harold Urey’s discovery, the essential component
of heavy water, was much easier and less expensive to separate from
hydrogen than U235 was from U238 and much simpler to acquire than
plutonium.
Each kilogram of heavy hydrogen equaled about 85,000 tons
TNT equivalent.1622 eoretically, 12 kilograms of liquid heavy hydrogen—
26 pounds—ignited by one atomic bomb would explode with a force
equivalent to 1 million tons of TNT.
So far as Oppenheimer and his group
knew at the beginning of the summer, an equivalent fission explosion would
require some 500 atomic bombs.1623
at reckoning alone would have been enough to justify devoting the
summer to imagining the Super a little way out of the darkness.
Teller found
something else as well, or thought he did, and with his usual pellmell facility
he scattered it before them.
ere are many other thermonuclear reactions
besides the D + D reactions.
Bethe had examined a number of them
methodically when looking for those that energized massive stars.
Now
Teller offered several which a fission bomb or a Super might inadvertently
trigger.
He proposed to the assembled luminaries the possibility that their
bombs might ignite the earth’s oceans or its atmosphere and burn up the
world, the very result Hitler occasionally joked about with Albert Speer.
“I didn’t believe it from the first minute,” Bethe scoffs.
“Oppie took it
sufficiently seriously that he went to see Compton.
I don’t think I would
have done it if I had been Oppie, but then Oppie was a more enthusiastic
character than I was.1624 I would have waited until we knew more.”
Oppenheimer had other urgent business with Compton in any case: the
Super itself.
Not to risk their loss, the bomb-project leaders were no longer
allowed to fly.
Oppenheimer tracked Compton by telephone at the
beginning of a July weekend to a country store in northern Michigan where
he had stopped to pick up the keys to his lakeside summer cottage, got
directions and caught the next train east.
In the meantime Bethe applied
himself to Teller’s calculations.
e Cornell physicist’s instant skepticism gives perspective to Compton’s
melodramatic recollection of his meeting with Oppenheimer:
I’ll never forget that morning.
I drove Oppenheimer from the railroad station down to the beach
looking out over the peaceful lake.
ere I listened to his story....
1625
Was there really any chance that an atomic bomb would trigger the explosion of the nitrogen in
the atmosphere or the hydrogen in the ocean?
is would be the ultimate catastrophe.
Better to
accept the slavery of the Nazis than to run a chance of drawing the final curtain on mankind!
We agreed there could be only one answer.
Oppenheimer’s team must go ahead with their
calculations.
Bethe already had.
“I very soon found some unjustified assumptions in
Teller’s calculations which made such a result extremely unlikely, to say the
least.
Teller was very soon persuaded by my arguments.” 1626 e arguments
—Bethe’s and others’—against a runaway explosion appear most
authoritatively in a technical history of the bomb design program prepared
under Oppenheimer’s supervision immediately aer the war:
It was assumed that only the most energetic of several possible [thermonuclear] reactions would
occur, and that the reaction cross sections were at the maximum values theoretically possible.
Calculation led to the result that no matter how high the temperature, energy loss would exceed
energy production by a reasonable factor.
At an assumed temperature of three million electron
volts [compare the 35,000 eV known for D + D] the reaction failed to be self-propagating by a
factor of 60.
is temperature exceeded the calculated initial temperature of the deuterium
reaction by a factor of 100, and that of the fission bomb by a larger factor....
e impossibility of
igniting the atmosphere was thus assured by science and common sense.1627
Oppenheimer returned to that good news and they proceeded with the
Super.
Teller recaptures the mood: “My theories were strongly criticized by
others in the group, but together with new difficulties, new solutions
emerged.
e discussions became fascinating and intense.
Facts were
questioned and the questions were answered by still more facts....
A spirit
of spontaneity, adventure, and surprise prevailed during those weeks in
Berkeley, and each member of the group helped move the discussion toward
a positive conclusion.
”1628
ere was serious trouble with Teller’s D + D Super.
e reactions would
proceed too slowly to reach ignition before the fission trigger blew the
assembly apart.
Konopinski came to the rescue: “Konopinski suggested that,
in addition to deuterium, we should investigate the reactions of the heaviest
form of hydrogen, tritium.” is, Teller explains, was at that time “only...
a
conversational guess.” 1629 One tritium reaction of obvious interest was the
fusion of a deuterium nucleus with a tritium nucleus, D + T, which results in
the formation of a helium nucleus with the ejection of a neutron and the
release of 17.6 MeV of energy.
e D + T reaction kindled at a mere 5,000
eV, which corresponds to a temperature of 40 million degrees.
But since
tritium does not exist on earth it would have to be created.
Neutrons
bombarding an isotope of lithium, Li6, would transmute some of that light
metal to tritium much as neutrons made plutonium from U235, but the only
obvious source of such necessarily copious quantities of neutrons was
Fermi’s unproven pile.
e luminaries did, however, consider the possibility
of making tritium within the Super itself by packing the bomb with a dry
form of lithium, lithium deuteride.1630 But lithium in its natural form, like
uranium in its natural form, contained too little of the desired isotope; to be
effective, the Li6 would have to be separated.
But lithium—element number
3 on the periodic table—would be much easier to separate than uranium...
So the arguments progressed across the pleasant Berkeley summer.
“We
were forever inventing new tricks,” Bethe says, “finding ways to calculate,
and rejecting most of the tricks on the basis of the calculations.
Now I could
see at first-hand the tremendous intellectual power of Oppenheimer who
was the unquestioned leader of our group....
e intellectual experience
was unforgettable.” 1631
At the end of the summer, merging the Serber subgroup’s work with their
own, the luminaries concluded that the development of an atomic bomb
would require a major scientific and technical effort.
1632 Glenn Seaborg
heard Oppenheimer’s deduction from that outcome at a meeting of the Met
Lab technical council in Chicago on September 29.
“Fast neutron work has
no home,” Seaborg paraphrases the Berkeley theoretician “[and] may need
one.” 1633 “Oppenheimer has plans in mind for fast neutron work,” Compton
told the council.
Oppenheimer was scouting a site where the bomb might be
designed and assembled.
He thought such an operation might find a home
in Cincinnati or with the plutonium production piles in Tennessee.
1634
* * *
James Bryant Conant heard the results of the Berkeley summer study at a
meeting of the S-l Executive Committee in late August 1942 and jotted
down a page of notes under the heading “Status of the Bomb.
”1635, 1636 e fission bomb, he wrote, would explode according to the luminaries with
“150 times energy of previous calculation” but, bad news, would require a
critical mass “6 times the previous [estimated] size[:] 30 kg U235.” Twelve
kilograms of U235 were enough to explode, Conant noted, but inefficiently
with “only 2% of energy.” News of the Super then startled the NDRC
chairman to a slip of the pencil:
To denotate [sic: detonate] 5–10 kg of heavy hydrogen liquid would require 30 kg U235
If you use 2 or 3 Tons of liquid deuterium and 30 kg U235 this would be equivalent 108 [i.e., 100,000,000] tons of TNT.
Estimate devastation area of 1000 sq.
km [or] 360 sq miles.
Radioactivity lethal over same area for
a few days.
Conant then drew a bold line with a steady hand and initialed the file note
“JBC.” As an aerthought or at a later time he added: “S-l Executive
Committee thinks the above probable.
Heavy water is being pushed as hard
as it can.
[First] 100 kg of D will be available by fall of 1943 before 60 kg of
U235 will be ready!”
A formal status report went off immediately from the Executive
Committee to Bush.
It predicted enough fissionable material for a test in
eighteen months—by March 1944.
It estimated that a 30-kilogram bomb of
U235 “should have a destructive effect equivalent to the explosion of over
100,000 tons of TNT,” much more than the mere 2,000 tons estimated
earlier.
And it dramatically announced the Super:
If this [U235] unit is used to detonate a surrounding mass of 400 kg of liquid deuterium, the
destructiveness should be equivalent to that of more than 10,000,000 tons of TNT.
is should
devastate an area of more than 100 square miles.
e committee—Briggs, Compton, Lawrence, Urey, Eger Murphree and
Conant—concluded by judging the bomb project important beyond all
previous estimates: “We have become convinced that success in this
program before the enemy can succeed is necessary for victory.
We also
believe that success of this program will win the war if it has not previously
been terminated.”
On August 29 Bush bumped the status report up to the Secretary of War,
noting that “the physicists of the Executive Committee are unanimous in
believing that this large added factor [i.e., the Super] can be obtained....
e ultimate potential possibilities are now considered to be very much
greater than at the time of the [last] report.
”1637
e hydrogen bomb was thus under development in the United States
onward from July 1942.
* * *
e problem that Leo Szilard would call “the trouble at Chicago”—the
problem of authority and responsibility for pile-cooling design and much
more—erupted in a brief rebellion at the Met Lab in September.
Stone &
Webster, the construction engineers the Army had hired, had spent the
summer studying plutonium production.
“Classical engineers,” Leona
Woods calls them, “who knew bridges and structures, canals, highways, and
the like, but who had a very weak grasp or none at all of what was needed in
the new nuclear industry.” e firm sent one of its best engineers to brief
Met Lab leaders on production plans.
“e scientists sat deadly still with
curled lips.
e briefer was ignorant; he enraged and frightened
everyone.
”1638
An exasperated Compton protégé, Volney Wilson, an idealistic young
physicist responsible for pile instrumentation, called a confrontation
meeting soon aerward on a hot autumn evening.
(As a student Wilson had
analyzed the motions of swimming fish and invented the competition
swimming style known as the Dolphin; with it he had won in Olympics
tryouts in 1938 but then suffered disqualification because the style was new
and thus unauthorized, a purblindness on the part of the Olympics judges
which may have conditioned Wilson’s attitude toward authority.) In his
memoirs Compton mixes up the autumn meeting with the similar
disagreement in June; Woods, who worked for Wilson, remembers it better:
We (some 60 or 70 scientists) assembled quietly in the commons room at Eckhart Hall, open
windows bringing hot, humid air in with an infinitesimal breeze.
No one spoke—it was a Quaker
meeting.
Finally Compton entered carrying a Bible....
Compton thought that the issue of Wilson’s meeting was whether the plutonium production
should be undertaken by large-scale industry or should be carried out by the scientists of the
Metallurgical Project, keeping control in their hands.1639 Instead, it seemed to me that the primary issue was to get rid of Stone & Webster.
1640
Compton vouchsafed a parable.
Without introduction he opened his Bible
to Judges 7: 5–7 and read to Leo Szilard and Enrico Fermi, to Eugene
Wigner, to John Wheeler and threescore serious scientists the story of how
the Lord helped Gideon sort among His people to find a few good men to
fight the Midianites when there were too many volunteers at hand to
demonstrate clearly that the victory would be entirely the work of the Lord.
“When Compton finished reading,” Woods remembers, “he sat down.” Not
surprisingly, “there was more Quaker-meeting silence.” Or astonishment.
1641
en Volney Wilson stood to direct “well-considered fire and brimstone...
at the incompetence of Stone & Webster.” Many others in the group spoke as
well, all opposing the Boston engineers.
“Aer a while, silence fell and finally
everyone got up and disbanded.” Compton had reduced the discussion to a
demand that the Met Lab capitulate to his authority.
Fortunately the
assembly of scientists ignored him.
e Army would soon move the
responsibility for plutonium production into more experienced hands than
Stone & Webster’s.
When the change was proposed Compton eagerly
endorsed it.
Szilard responded to the struggles at the Met Lab with anger that by now,
aer four years of frustration, had begun to harden into stoicism.
Late in
September he draed a long memorandum to his colleagues that addressed
specific Met Lab problems but also considered the deeper issue of the
responsibility of scientists for their work.
In dra and more moderately in
finished form his examination by turns compliments and savages Compton’s
leadership: “In talking to Compton I frequently have the feeling that I am
overplaying a delicate instrument.” 1642, 1643 Beyond personality Szilard pointed to a destructive abdication by those whom Compton led: “I have
oen thought...
that things would have been different if Compton’s
authority had actually originated with our group, rather than with the
OSRD.
”1644 He elaborates in the finished memorandum:
e situation might be different if Compton considered himself as our representative in
Washington and asked in our name for whatever was necessary to make our project successful.
He
could then refuse to make a decision on any of the issues which affect our work until he had an
opportunity fully to discuss the matter with us.1645
Viewed in this light, it ought to be clear to us that we, and we alone, are to be blamed for the
frustration of our work.
An authoritarian organization had moved in—had been allowed to move in
—to take over work that had been democratically begun.
“ere is a
sprinkling of democratic spots here and there, but they do not form a
coherent network which could be functional.
”1646 Szilard was convinced that
authoritarian organization was no way to do science.
So were Wigner and
the more detached Fermi.
“If we brought the bomb to them all ready-made
on a silver platter,” Szilard remembers hearing Fermi say, “there would still
be a fiy-fiy chance that they would mess it up.” 1647 But beyond debating
the virtues of contractors and cooling systems only Szilard continued to
rebel:
We may take the stand that the responsibility for the success of this work has been delegated by the
President to Dr.
Bush.
It has been delegated by Dr.1648 Bush to Dr.
Conant.
Dr.
Conant delegates this responsibility (accompanied by only part of the necessary authority) to Compton.
Compton
delegates to each of us some particular task and we can lead a very pleasant life while we do our
duty.
We live in a pleasant part of a pleasant city, in the pleasant company of each other, and have
in Dr.
Compton the most pleasant “boss” we could wish to have.
ere is every reason why we
should be happy and since there is a war on, we are even willing to work overtime.
Alternatively, we may take the stand that those who have originated the work on this terrible
weapon and those who have materially contributed to its development have, before God and the
World, the duty to see to it that it should be ready to be used at the proper time and in the proper
way.I believe that each of us has now to decide where he feels that his responsibility lies.
e Army had been involved in the bomb project since June, but the Corps
of Engineers’ Colonel Marshall had been unable to drive the project ahead of
other national military priorities.
Divided between the OSRD and the Army
it began to look as if it might lose its way.
Bush thought he saw a solution in
an authoritative new Military Policy Committee that would retain the
project under partly civilian control but delegate direction to a dynamic
Army officer and back him up.
“From my own point of view,” he wrote at the
end of August 1942, “faced as I am with the unanimous opinion of a group
of men that I consider to be among the greatest scientists in the world,
joined by highly competent engineers, I am prepared to recommend that
nothing should stand in the way of putting this whole affair through to
conclusion...
even if it does cause moderate interference with other war
efforts.
”1649
Bush had discussed his problems with the general in charge of the Army
Services of Supply, Brehon Somervell.
Independently Somervell worked out
a solution of his own: assigning entire responsibility to the Corps of
Engineers, which was under his command.
e program would need a
stronger leader.
He had a man in mind.
In mid-September he sought him
out.
“On the day I learned that I was to direct the project which ultimately
produced the atomic bomb,” Albany-born Leslie Richard Groves wrote later,
“I was probably the angriest officer in the United States Army.” 1650 e West
Point graduate, forty-six years old in 1942, goes on to explain why:
It was on September 17, 1942, at 10:30 a.m., that I got the news.
I had agreed, by noon that day, to
telephone my acceptance of a proposed assignment to duty overseas.
I was then a colonel in the
Army Engineers, with most of the headaches of directing ten billion dollars’ worth of military
construction in the country behind me—for good, I hoped.
I wanted to get out of Washington, and
quickly.
Brehon B.
Somervell...
my top superior, met me in a corridor of the new House of
Representatives Office Building when I had finished testifying about a construction project before
the Military Affairs Committee.
“About that duty overseas,” General Somervell said, “you can tell them no.”
“Why?” I inquired.
“e Secretary of War has selected you for a very important assignment.”
“Where?”
“Washington.”
“I don’t want to stay in Washington.”
“If you do the job right,” General Somervell said carefully, “it will win the war.”
Men like to recall, in later years, what they said at some important or possibly historic moment
in their lives....
I remember only too well what I said to General Somervell that day.
I said, “Oh.”
As deputy chief of construction for the entire U.S.
Army, Groves knew
enough about the bomb project to recognize its dubious claim to decisive
effect and be thoroughly disappointed.
He had just finished building the
Pentagon, the most visible work of his career.
He had seen the S-l budget; it
amounted in total to less than he had been spending in a week.
He wanted
assignment commanding troops.
But he was career Army and understood
he hardly had a choice.
He crossed the Potomac to the Pentagon office of
Somervell’s chief of staff, Brigadier General Wilhelm D.
Styer, for a briefing.
Styer implied the job was well along and ought to be easy.
e two officers
worked up an order for Somervell to sign authorizing Groves “to take
complete charge of the entire...
project.
”1651 Groves discovered he would be
promoted to brigadier—for authority and in compensation—in a matter of
days.
He proposed to delay official appointment until the promotion came
through.
“I thought that there might be some problems in dealing with the
many academic scientists involved in the project,” he remembers of his
initial innocence, “and I felt that my position would be stronger if they
thought of me from the first as a general instead of as a promoted
colonel.
”1652 Styer agreed.
Groves was one inch short of six feet tall, jowly, with curly chestnut hair,
blue eyes, a sparse mustache and sufficient girth to balloon over his webbing
belt above and below its brass military buckle.1653 Leona Woods thought he
might weigh as much as 300 pounds; he was probably nearer 250 then,
though he continued to expand.
He had graduated from the University of
Washington in 1914, studied engineering intensely for two years at MIT and
gone on to West Point, where he graduated fourth in his class in 1918.
Years
at the Army Engineer School, the Command and General Staff College and
the Army War College in the 1920s and 1930s completed his extensive
education.
He had seen duty in Hawaii, Europe and Central America.
His
father was a lawyer who le the law for the ministry and served in a country
parish and an urban, working-class church before Grover Cleveland’s
Secretary of War convinced him to enlist as an Army chaplain on the
Western frontier.
“Entering West Point fulfilled my greatest ambition,”
Groves testifies.
“I had been brought up in the Army, and in the main had
lived on Army posts all my life.
I was deeply impressed with the character
and outstanding devotion to duty of the officers I knew.
”1654 e dynamic
engineer was married, with a thirteen-year-old daughter and a plebe son at
West Point.
“A tremendous lone wolf,” one of his subordinates describes Groves.
1655
Another, whose immediate superior Groves was about to become, distills
their years together into grudgingly admiring vitriol.
Lieutenant Colonel
Kenneth D.
Nichols—balding, bespectacled, thirty-four in 1942, West Point,
Ph.D.
in hydraulic engineering at Iowa State—remembers Groves as
the biggest sonovabitch I’ve ever met in my life, but also one of the most capable individuals.
He
had an ego second to none, he had tireless energy—he was a big man, a heavy man but he never
seemed to tire.
He had absolute confidence in his decisions and he was absolutely ruthless in how
he approached a problem to get it done.
But that was the beauty of working for him—that you
never had to worry about the decisions being made or what it meant.
In fact I’ve oen thought that
if I were to have to do my part all over again, I would select Groves as boss.
I hated his guts and so
did everybody else but we had our form of understanding.
1656
Nichols’ previous boss, Colonel Marshall, had worked out of an office in
Manhattan (where in August he had disguised the project to build an atomic
bomb behind the name Manhattan Engineer District).
But decisions of
priority and supply were made in wartime in hurly-burly Washington
offices, not in Manhattan, and to fight those battles the colonel had chosen
the capable Nichols.
Groves therefore sought out Nichols next aer Styer.
And found the project in even worse condition than he had feared: “I was
not happy with the information I received; in fact, I was horrified.” 1657
He took Nichols with him to the Carnegie Institution on P Street to
confront Vannevar Bush.
Somervell had overlooked clearing Groves’
appointment with Bush and the OSRD director was infuriated.
He evaded
Groves’ questions brusquely, which puzzled Groves.
Controlling his anger
until Groves and Nichols le, Bush then paid Styer a visit, which he
describes in a contemporary memorandum:
I told him (1) that I still felt, as I had told him and General Somervell previously, that the best move was to get the military commission first, and then the man to carry out their policies second;
(2) that having seen General Groves briefly, I doubted whether he had sufficient tact for such a
job.1658
Styer disagreed on (1) and I simply said I wanted to be sure he understood my
recommendation.
On (2) he agreed the man is blunt, etc., but thought his other qualities would
overbalance....
I fear we are in the soup.
Bush changed his mind within days.
Groves immediately tackled his worst
problems and solved them.
One of the first issues the heavyweight colonel had raised with Nichols
was ore supply: was there sufficient uranium on hand?
Nichols told him
about a recent and fortuitous discovery: some 1,250 tons of extraordinarily
rich pitchblende—it was 65 percent uranium oxide—that the Union Minière
had shipped to the United States in 1940 from its Shinkolobwe mine in the
Belgian Congo to remove it beyond German reach.
Frédéric Joliot and
Henry Tizard had independently warned the Belgians of the German danger
in 1939.
e ore was stored in the open in two thousand steel drums at Port
Richmond on Staten Island.
e Belgians had been trying for six months to
alert the U.S.
government to its presence.
On Friday, September 18, Groves
sent Nichols to New York to buy it.
On Saturday Groves draed a letter in the name of Donald Nelson, the
civilian head of the War Production Board, assigning a first-priority AAA
rating to the Manhattan Engineer District.
Groves personally carried the
letter to Nelson.
“His reaction was completely negative; however, he quickly
reversed himself when I said that I would have to recommend to the
President that the project should be abandoned because the War Production
Board was unwilling to co-operate with his wishes.
”1659 Groves was bluffing
but it was not the bluster that swayed Nelson; he had probably heard by then
from Bush and Henry Stimson.
He signed the letter.
“We had no major
priority difficulties,” notes Groves, “for nearly a year.
”1660
e same day Groves approved a directive that had been languishing on
his predecessor’s desk throughout the summer for the acquisition of 52,000
acres of land along the Clinch River in eastern Tennessee.
Site X, the Met
Lab called it.
District Engineer Marshall had thought to wait to buy the land
at least until the chain reaction was proved.
On September 23, the following Wednesday, Groves’ promotion to
brigadier came through.
He hardly had time to pin on his stars before
attending a command performance in the office of the Secretary of War
called to assemble Bush’s outmaneuvered Military Policy Committee with
Stimson, Army Chief of Staff George Marshall, Bush, Conant, Somervell,
Styer and an admiral on hand.
Groves described how he intended to operate.
Stimson proposed a nine-man committee to supervise.
Groves held out for a
more workable three and won his point.
Discussion continued.
Abruptly
Groves asked to be excused: he needed to catch a train to Tennessee, he
explained, to inspect Site X.
e startled Secretary of War agreed and Leslie
Richard Groves, the new broom that would sweep the Manhattan Engineer
District clean, departed for Union Station.
“You made me look like a million
dollars,” Somervell praised Groves when he got back to Washington.
“I’d told
them that if you were put in charge, things would really start moving.” 1661
ey did.
* * *
Enrico Fermi began planning a full-scale chain-reacting pile in May 1942
when one of the exponential piles his team built in the west stands of Stagg
Field indicated its k at infinity would muster 0.995.
1662 e Met Lab was searching out higher-quality graphite and sponsoring production of pure
uranium metal, denser than oxide; those and other improvements should
push k above 1.0.
“I remember I talked about the experiment on the Indiana
dunes,” Fermi told his wife aer the war, “and it was the first time I saw the
dunes....
I liked the dunes: it was a clear day, with no fog to dim colors....
We came out of the water, and we walked along the beach.
”1663
As they began preparations that summer Leona Woods remembers
swimming “in frigid Lake Michigan every aernoon at five o’clock, off the
huge breakwater rocks at the 55th street promontory”—she, Herbert
Anderson, Fermi.1664 She was still a graduate student, twenty-two and shy.
“One evening, Enrico gave a party, inviting Edward and [Mici] Teller, Helen
and Robert Mulliken (my research professor), and Herb Anderson, John
Marshall, and me.
”1665 ey played Murder, the parlor game then in fashion.
“e second the lights went out on this particular evening, I shrank into a
corner and listened with astonishment to these brilliant, accomplished,
famous sophisticated people shrieking and poking and kissing each other in
the dark like little kids.” All nice people are shy, Fermi consoled her when he
knew her better; he had always been dominated by shyness.
She records his
sly self-mockery: “As he frequently said, he was amazed when he thought
how modest he was.” 1666
Woods was finishing her thesis work during the summer but sometimes
helped Anderson scour Chicago for lumber.
CP-1—Chicago Pile Number
One—Fermi planned to build in the form of a sphere, the most efficient
shape to maximize k.
Since the pile’s layers of graphite bricks would enlarge
concentrically up to its equator, they would need external support, and
wood framing was light and easy to shape and assemble.
“I was the buyer for
a lot of lumber,” Anderson says.
“I remember the Sterling Lumber Company,
how amazed they were by the orders I gave them, all with double X priority.
But they delivered the lumber with no questions asked.
ere was almost no
constraint on money and priority to get what we wanted.” 1667
Horseback riding one Saturday aernoon in the Cook County Forest
Preserve twenty miles southwest of Chicago, Arthur and Betty Compton
found an isolated, scenic site for the pile building, a terminal moraine
forested with hawthorne and scrub oak known as the Argonne Forest.
e
Army’s Nichols negotiated with the county to use the land; Stone & Webster
began planning construction.
e Fermis rented a house from a businessman moving to Washington for
war work; since they were enemy aliens and not allowed to own a shortwave
radio the man had to have his big all-band Capehart temporarily disabled of
its long-distance frequencies, though it continued to supply dance music to
the party room on the third floor.
Fermi was angry to find his mail being
opened and complained indignantly until the practice was stopped (or
managed more surreptitiously).
e Comptons gave a series of parties to
welcome newcomers to the Met Lab.
“At each of these parties,” Laura Fermi
writes, “the English film Next of Kin was shown.
It depicted in dark tones the
consequences of negligence and carelessness.
A briefcase laid down on the
floor in a public place is stolen by a spy.
English military plans become
known to the enemy.
Bombardments, destruction of civilian homes, and an
unnecessarily high toll of lives on the fighting front are the result....
Willingly we accepted the hint and confined our social activities to the
group of ‘metallurgists.’ ” 1668 Compton, who describes himself as “one of
those who must talk over important problems with his wife,” arranged
uniquely to have Betty Compton cleared.1669 None of the other wives was
supposed to know about her husband’s work.
Laura Fermi found out, like
many others, only at the end of the war.
In mid-August Fermi’s group could report a probable k for a graphite-
uranium oxide pile of “close to 1.04.” 1670 ey were working on control-rod
design and testing the vacuum properties of both metal sheet and balloon
cloth.
e cloth was Anderson’s idea, a possible alternative to canning the
pile to exclude neutron-absorbing air.
It proved serviceable and Anderson
followed up: “For the balloon cloth enclosure I went to the Goodyear
Rubber Company in Akron, Ohio.
e company had a good deal of
experience in building blimps and rubber ras but a square balloon 25’ on a
side seemed a bit odd to them.” ey made it anyway, “with no questions
asked.” 1671 It should be good for a 1 percent improvement in k.
1672
Between September 15 and November 15 Anderson, Walter Zinn and
their crews also built sixteen successive exponential piles in the Stagg Field
west stands to measure the purity of the various shipments of graphite,
uranium oxide and metal they had begun to receive in quantity.
Not all the
uranium was acceptable.
But Mallinckrodt Chemical Works in St.
Louis,
specialists at handling the ether necessary for oxide extraction, began
producing highly purified brown oxide at the rate of thirty tons a month,
and the National Carbon Company and a smaller supplier, by using purified
petroleum coke for raw material and doubling furnace time, significantly
improved graphite supplies (graphite is molded as coke, then baked in a
high-temperature electric-arc oven for long hours until it crystallizes and its
impurities vaporize away).
By September regular deliveries began to arrive
in covered trucks.
Physicists doubled as laborers to unload the bricks and
cans and pass them into the west stands for finishing.
Walter Zinn took charge of preparing the materials for the pile.
e
graphite came in from various manufacturers as rough 4¼ by 4¼-inch bars
in 17- to 50-inch lengths.
So that the bars would fit closely together they had
to be smoothed and cut to standard 16½-inch lengths.
About a fourth of
them also had to be drilled for the lumps of uranium they would hold.
A few
required slots machined through to make channels for control rods.
e
uranium oxide needed to be compressed into what the physicists called
“pseudospheres”—stubby cylinders with round-shouldered ends—for which
purpose the press from the Jersey City junkyard had been shipped to
Chicago the previous winter.1673
For crew Zinn had half a dozen young physicists, a thoroughly able
carpenter and some thirty high school dropouts earning pocket money until
their dra notices came through.
ey were Back of the Yards boys from the
tough neighborhood beyond the Chicago stockyards and Zinn improved the
fluency of his swearing keeping them in line.
Machining the graphite was like sharpening thousands of giant pencils.
Zinn used power woodworking tools.
A jointer first made two sides of each
graphite brick perpendicular and smooth; a planer finished the other two
surfaces; a swing saw cut the bricks to length.
at processing produced 14
tons of bricks a day; each brick weighed 19 pounds.
To drill the blind, round-bottomed 3¼-inch holes for the uranium
pseudospheres, two to a brick, Zinn adapted a heavy lathe.
He mounted a
3¼-inch spade bit in the headstock of the lathe, where the material to be
turned would normally be mounted, and forced the graphite up against the
tool with the lathe carriage.
Dull bits caused problems.
Zinn tried tough
carballoy bits first, but they were tedious to resharpen.
He began making bits
from old steel files, sharpening them by hand whenever they dulled.
One
sharpening was good for 60 holes, about an hour’s work.
Before they were
through they would shape and finish 45,000 graphite bricks and drill 19,000
holes.
General Groves made his first appearance at the Met Lab on October 5
and delivered his first pronouncement.
e technical council was debating
cooling systems again.
“e War Department considers the project
important,” Seaborg paraphrases Groves’ formula, which they would all
learn by heart.
“ere is no objection to a wrong decision with quick results.
If there is a choice between two methods, one of which is good and the other
looks promising, then build both.” 1674 Get the cooling-system decision into
Compton’s hands by Saturday night, Groves demanded.
It was Monday.
ey
had been debating for months.
Groves moved on to Berkeley more impressed with their work than his
Met Lab auditors realized.
“I le Chicago feeling that the plutonium process
seemed to offer us the greatest chances for success in producing bomb
material,” he recalls.
“Every other process...
depended upon the physical
separation of materials having almost infinitesimal differences in their
physical properties.” Transmutation by chain reaction was entirely new, but
the rest of the plutonium process, chemical separation, “while extremely
difficult and completely unprecedented, did not seem to be impossible.” 1675
At the beginning of the month, to Compton’s great relief, the brigadier
had convinced E.
I.
du Pont de Nemours, the Delaware chemical and
explosives manufacturers, to take over building and running the plutonium
production piles under subcontract to Stone & Webster.
He meant to involve
the industrial chemists more extensively than that—meant for them to take
over the plutonium project in its entirety.
Du Pont resisted the increasing
encroachment.
“Its reasons were sound,” writes Groves: “the evident physical
operating hazards, the company’s inexperience in the field of nuclear
physics, the many doubts about the feasibility of the process, the paucity of
proven theory, and the complete lack of essential technical design data.” 1676
Du Pont also suspected, once it had sent an eight-man review team to
Chicago at the beginning of November, that the plutonium project was the
least promising of the several then under development and might even fail,
tarnishing the company’s reputation.
Nor was it happy at the prospect of
identifying itself with a secret weapon of mass destruction; it still
remembered the general condemnation it had received for selling munitions
to Britain and France before the United States entered the First World War.
Groves told the Du Pont executive committee that the Germans were
probably hard at work and the only defense against a Nazi atomic bomb
would be an American bomb.
And added what he took to be a clinching
argument: “If we were successful in time, we would shorten the war and thus
save tens of thousands of American casualties.
”1677 e second week in
November Du Pont admitted the possibility of regular production by 1945
and accepted the assignment (limiting itself to a profit of one dollar to avoid
arms-merchant stigma), but made its skepticism and reluctance clear.
By then Stone & Webster’s construction workers had gone on strike.
e
pile building scheduled for completion by October 20 would be indefinitely
delayed.
Fermi lived with the problem only long enough to recalculate the
risks of pile control.
In early November he cornered Compton in his office
and proposed an alternative site: the doubles squash court where his team
had built its series of exponential piles.
A k greater than 1.0 presented an
entirely different order of risk from a k of less than 1.0 , however; Compton
had, in Seaborg’s words, a “dreadful decision” to make.
1678 “We did not see
how a true nuclear explosion, such as that of an atomic bomb, could possibly
occur,” Compton writes with more calm than he probably felt at the time.
“But the amount of potentially radioactive material present in the pile would
be enormous and anything that would cause excessive ionizing radiation in
such a location would be intolerable.
”1679 He asked for Fermi’s analysis of the
probability of control.
No doubt Fermi discussed the various hand and automatic control rods he
planned for the pile.
But even slow-neutron fission generations had been
calculated to multiply in thousandths of a second, which might flash the pile
to dangerous levels of heat and radiation before any merely mechanical
control system could move into position.
e “most significant fact assuring
us that the chain reaction could be controlled,” says Compton, was one of
the Richard Roberts team’s earliest discoveries at the Carnegie Institution’s
Department of Terrestrial Magnetism following Bohr’s announcement of the
discovery of fission in 1939—in Compton’s words, that “a certain small
fraction of the neutrons associated with the fission process are not emitted at
once but come off a few seconds aer fission occurs.
”1680 With a pile
operating at k only marginally above 1.0 , such delayed neutrons would slow
the response sufficiently to allow time for adjustment.1681
For once Compton made a quick decision: with control seemingly
assured, he allowed Fermi to build CP-1 in the west stands.
He chose not to
inform the president of the University of Chicago, Robert Maynard
Hutchins, reasoning that he should not ask a lawyer to judge a matter of
nuclear physics.
“e only answer he could have given would have been—
no.
And this answer would have been wrong.
So I assumed the responsibility
myself.” 1682 e word meltdown had not yet entered the reactor engineer’s
vocabulary—Fermi was only then inventing that specialty—but that is what
Compton was risking, a small Chernobyl in the midst of a crowded city.
Except that Fermi, as he knew, was a formidably competent engineer.
* * *
In mid-November Fermi reorganized his team into two twelve-hour shis, a
day crew under Walter Zinn (who continued to supervise materials
production as well), a night crew under Herbert Anderson.
Construction
began on Monday morning, November 16, 1942.
From the balcony of the
doubles squash court in the west stands of Stagg Field Fermi directed the
hanging of the cubical dark-gray Goodyear balloon as his men hauled it into
place with block and tackle.
It dominated the room: bottom panel smoothed
on the floor, top and three sides secured to the ceiling and the walls, the
fourth side facing the balcony furled up out of the way like an awning.
Someone drew a circle on the floor panel to locate the first layer of graphite
and without ceremony the crew began positioning the dark, slippery bricks.
e first layer was “dead” graphite that carried no load of uranium: solid
crystalline carbon to diffuse and slow the neutrons that fission would
generate.
Up the pile as it stacked, the crews would alternate one layer of
dead graphite with two layers of bricks each drilled and loaded with two
five-pound uranium pseudospheres.
at created a cubic cell of neutron-
diffusing graphite around every lump of uranium.
To build the wooden framing, Herbert Anderson recalls, “Gus Knuth, the
millwright, would be called in.1683 We would show him...
what we wanted,
he would take a few measurements, and soon the timbers would be in place.
ere were no detailed plans or blueprints for the frame or the pile.” Since
they had batches of graphite, oxide and metal of varying purity, they
improvised the placement of materials as they went along.
Fermi, says
Anderson, “spent a good deal of time calculating the most effective location
for the various grades of [material] on hand.
”1684
ey were soon averaging not quite two layers a shi, handing the bricks
along from their delivery skids, sliding them to the workers on the pile,
singing together to pass the time.
1685 e bricks in the dead graphite layers
alternated direction, three running east and west and the next three north
and south.
at gave support to the oxide layers, which all ran together from
front to back except at the outer edges, where dead graphite formed an outer
shell.
e physicist bricklayers had to be careful to line up the slots for the
ten control-rod channels that passed at widely distributed points completely
through the pile.
“A simple design for a control rod was developed,” says
Anderson, “which could be made on the spot: cadmium sheet nailed to a flat
wood strip....
e [thirteen-foot] strips had to be inserted and removed by
hand.
Except when the reactivity of the pile was being measured, they were
kept inside the pile and locked using a simple hasp and padlock, the only
keys to which were kept by Zinn and myself.
”1686 Cadmium, which has a
gargantuan absorption cross section for slow neutrons, held the pile
quiescent.
As it grew they assembled wooden scaffolding to stand on and ran loads
of bricks up to the working face on a portable materials elevator.
Before the
arrival of the elevator, during the period when they were building large
exponential piles, they had simply leaned over from the precarious 2 by 12-
inch scaffolding and reached the bricks up from the men on the floor below.
Groves walked in on them one day and dressed them down for risking their
necks.
e elevator appeared unbidden soon aer.
When they achieved the fieenth layer Zinn and Anderson began
measuring neutron intensity at the end of each shi at a fixed point near the
center of the pile with the control rods removed.
ey used a boron
trifluoride counter Leona Woods had devised that worked much like a
Geiger counter, clicking off the neutron count.
Standard indium foils
bombarded to radioactivity by pile neutrons gave daily checks on the boron
counter’s calibration.
Fermi had complained to Segrè in October that he was
doing physics by telephone; now he moved a little closer to the work.
“Each
day we would report on the progress of the construction to Fermi,”
Anderson notes, “usually in his office in Eckhart Hall.
en we would
present our sketch of the layers that we had assembled and reach some
agreement on what would be added during the following shis.
”1687 Fermi
took the raw boron-counter and indium measurements and calculated a
countdown.
As the pile approached its slow-neutron critical mass the
neutrons generated within it by spontaneous fission multiplied through
more and more generations before they were absorbed.
At k= 0.99 , for
example, each neutron would multiply through an average one hundred
generations before its chain of generations died out.
Fermi divided the
square of the radius of the pile by a measure of the intensity of radioactivity
the pile induced in indium and got a number that would decrease to zero as
the pile approached criticality.
At layer 15 the countdown stood at 390; at
layer 19 it dropped to 320.
1688 It was 270 at layer 25 and down to 149 at layer
36.As winter locked down, the unheated west stands turned bitterly cold.
Graphite dust blackened walls, floors, hallways, lab coats, faces, hands.
A
black haze dispersed light in the floodlit air.
White teeth shone.
Every
surface was slippery, hands and feet routine casualties of dropped blocks.
e men building the pile, liing tons of materials every shi, stayed warm
enough, but the unlucky security guards stationed at doors and entrances
froze.
Zinn scavenged rakish makeshi to thaw them out:
We tried charcoal fires in empty oil drums—too much smoke.
en we secured a number of
ornamental, imitation log, gas-fired fireplaces.
ese were hooked up to the gas mains, but they
gobbled up the oxygen and replaced it with fumes which burned the eyes....1689 e University of Chicago came to the rescue.
Years before, big league football had been banned from the campus;
we found in an old locker a supply of raccoon fur coats.
us, for a time we had the best dressed
collegiate-style guards in the business.
Fermi had originally designed his first full-scale pile as a 76-layer sphere.
Some 250 tons of better graphite from National Carbon now promised to
reduce neutron absorption below previous estimates; more than 6 tons of
high-purity uranium metal in the form of 2¼-inch cylinders began arriving
from Iowa State College at Ames, where one of the Met Lab’s chemistry
group leaders, Frank Spedding, had converted a laboratory to backyard mass
production.
“Spedding’s eggs,” dropped in place of oxide pseudospheres into
drilled graphite blocks that were then stacked in spherical configuration
close to the center of the CP-1 lattice, significantly increased the value of k.
Adjusting for the improvements, Fermi saw that they would not need to seal
the Goodyear balloon and evacuate the air from the pile and could eliminate
some 20 layers: his countdown should converge to zero, k = 1.0 , between
layers 56 and 57.
Instead of a sphere the pile would take the form of a
doorknob as big as a two-car garage, a flattened rotational ellipsoid 25 feet
wide at the equator and 20 feet high from pole to pole:
Anderson’s crew assembled this final configuration on the night of
December 1:
at night the construction proceeded as usual, with all cadmium covered wood in place.
When
the 57th layer was completed, I called a halt to the work, in accordance with the agreement we had
reached in the meeting with Fermi that aernoon.
All the cadmium rods but one were removed
and the neutron count taken following the standard procedure which had been followed on the
previous days.
It was clear from the count that once the only remaining cadmium rod was
removed, the pile would go critical.
I resisted great temptation to pull the final cadmium strip and
be the first to make a pile chain react.
However, Fermi had foreseen this temptation and extracted a
promise from me to make the measurement, record the result, insert all cadmium rods, and lock
them all in place.1690
Which Anderson dutifully did, and closed up the squash court and went
home to bed.
e pile as it waited in the dark cold of Chicago winter to be released to
the breeding of neutrons and plutonium contained 771,000 pounds of
graphite, 80,590 pounds of uranium oxide and 12,400 pounds of uranium
metal.
It cost about $1 million to produce and build.
Its only visible moving
parts were its various control rods.
If Fermi had planned it for power
production he would have shielded it behind concrete or steel and pumped
away the heat of fission with helium or water or bismuth to drive turbines to
generate electricity.
But CP-1 was simply and entirely a physics experiment
designed to prove the chain reaction, unshielded and uncooled, and Fermi
intended, assuming he could control it, to run it no hotter than half a watt,
hardly enough energy to light a flashlight bulb.
He had controlled it day by
day for the seventeen days of its building as its k approached 1.0 , matching
its responses with his estimates, and he was confident he could control it
when its chain reaction finally diverged.
What would he do if he was wrong?
one of his young colleagues asked him.
He thought of the damping effect of
delayed neutrons.
“I will walk away—leisurely,” he answered.
1691
“e next morning,” Leona Woods remembers—the beginning of the
fateful day, December 2, 1942—“it was terribly cold—below zero.
Fermi and
I crunched over to the stands in creaking, blue-shadowed snow and repeated
Herb’s flux measurement with the standard boron trifluoride counter.” Fermi
had plotted a graph of his countdown numbers; the new data point fell
exactly on the line he had extrapolated from previous measurements, a little
shy of layer 57:1692
Fermi discussed a schedule for the day with Zinn and Volney Wilson,
Woods continues; “then a sleepy Herb Anderson showed up....
Herb, Fermi
and I went over to the apartment I shared with my sister (it was close to the
stands) for something to eat.
I made pancakes, mixing the batter so fast that
there were bubbles of dry flour in it.
When fried, these were somewhat
crunchy between the teeth, and Herb thought I had put nuts in the batter.”
Outside was raw wind.
On the second day of gasoline rationing
Chicagoans jammed streetcars and elevated trains, leaving almost half their
usual traffic of automobiles at home.
e State Department had announced
that morning that two million Jews had perished in Europe and five million
more were in danger.
e Germans were preparing counterattack in North
Africa; American marines and Japanese soldiers struggled in the hell of
Guadalcanal.
Back we mushed through the cold, creaking snow....
Fiy-seventh Street was strangely empty.
Inside the hall of the west stands, it was as cold as outside.
We put on the usual gray (now black
with graphite) laboratory coats and entered the doubles squash court containing the looming pile
enclosed in the dirty, grayish-black balloon cloth and then went up on the spectators’ balcony.
e
balcony was originally meant for people to watch squash players, but now it was filled with control
equipment and read-out circuits glowing and winking and radiating some gratefully received
heat.
1693
e instrumentation included redundant boron trifluoride counters for
lower neutron intensities and ionization chambers for higher.
A wooden pier
extending out from the face of the pile supported automatic control rods
operated by small electric motors that would stand idle that day.
ZIP, a
weighted safety rod Zinn had designed, rode the same scaffolding.
A
solenoid-actuated catch controlled by an ionization chamber held ZIP in
position withdrawn from the pile; if neutron intensity exceeded the chamber
setting the solenoid would trip and gravity would pull the rod into position
to stop the chain reaction.
Another ZIP-like rod had been tied to the
balcony railing with a length of rope; one of the physicists, feeling foolish,
would stand by to chop the rope with an ax if all else failed.
Allison had even
insisted on a suicide squad, three young physicists installed with jugs of
cadmium-sulfate solution near the ceiling on the elevator they had used to
li graphite bricks; “several of us,” Wattenberg complains, “were very upset
with this since an accidental breakage of the jugs near the pile could have
destroyed the usefulness of the material.” 1694 George Weil, a young veteran
of the Columbia days, took up position on the floor of the squash court to
operate one of the cadmium control rods by hand at Fermi’s order.
Fermi
had scalers that counted off boron trifluoride readings with loud clicks and a
cylindrical pen recorder that performed a similar function silently, graphing
pile intensities in ink on a roll of slowly rotating graph paper.
For
calculations he relied on his own trusted six-inch slide rule, the pocket
calculator of its day.
Around midmorning Fermi began the crucial experiment.
First he
ordered all but the last cadmium rod removed and checked to see if the
neutron intensity matched the measurement Anderson had made the night
before.
With that first comparison Volney Wilson’s team working on the
balcony took time to adjust its monitors.
Fermi had calculated in advance
the intensity he expected the pile to reach at each step of the way as George
Weil withdrew the last thirteen-foot cadmium rod by measured increments.
When Wilson’s team was ready, writes Wattenberg, “Fermi instructed Weil
to move the cadmium rod to a position which was about half-way out.
[e
adjustment brought the pile to] well below critical condition.
e intensity
rose, the scalers increased their rates of clicking for a short while, and then
the rate became steady, as it was supposed to.” 1695 Fermi busied himself at
his slide rule, calculating the rate of increase, and noted the numbers on the
back.
He called to Weil to move the rod out another six inches.
“Again the
neutron intensity increased and leveled off.
e pile was still subcritical.
Fermi had again been busy with his little slide rule and seemed very pleased
with the results of his calculations.
Every time the intensity leveled off, it was
at the values he had anticipated for the position of the control rod.
”1696
e slow, careful checking continued through the morning.
A crowd
began to gather on the balcony.
Szilard arrived, Wigner, Allison, Spedding
whose metal eggs had flattened the pile.
Twenty-five or thirty people
accumulated on the balcony watching, most of them the young physicists
who had done the work.
No one photographed the scene but most of the
spectators probably wore suits and ties in the genteel tradition of prewar
physics and since it was cold in the squash court, near zero, they would have
kept warm in coats and hats, scarves and gloves.
e room was dingy with
graphite dust.
Fermi was calm.
e pile rising before them, faced with raw 4
by 6-inch pine timbers up to its equator, domed bare graphite above, looked
like an ominous black beehive in a bright box.
Neutrons were its bees,
dancing and hot.
Fermi called for another six-inch withdrawal.
Weil reached up to comply.
e neutron intensity leveled off at a rate outside the range of some of the
instruments.
Time passed, says Wattenberg, the watchers abiding in the
cold, while Wilson’s team again adjusted the electronics:
Aer the instrumentation was reset, Fermi told Weil to remove the rod another six inches.
e pile
was still subcritical.
e intensity was increasing slowly—when suddenly there was a very loud
crash!
e safety rod, ZIP, had been automatically released.
Its relay had been activated by an
ionization chamber because the intensity had exceeded the arbitrary level at which it had been set.
It was 11:30 a.m., and Fermi said, “I’m hungry.
Let’s go to lunch.” e other rods were put into the
pile and locked.1697
At two in the aernoon they prepared to continue the experiment.
Compton joined them.
He brought along Crawford Greenewalt, the tall,
handsome engineer who was the leader of the Du Pont contingent in
Chicago.
Forty-two people now occupied the squash court, most of them
crowded onto the balcony.
Fermi ordered all but one of the cadmium rods again unlocked and
removed.
He asked Weil to set the last rod at one of the earlier morning
settings and compared pile intensity to the earlier reading.
When the
measurements checked he directed Weil to remove the rod to the last setting
before lunch, about seven feet out.
e closer k approached 1.0 , the slower the rate of change of pile intensity.
Fermi made another calculation.
e pile was nearly critical.
He asked that
ZIP be slid in.
at adjustment brought the neutron count down.
“is
time,” he told Weil, “take the control rod out twelve inches.” Weil withdrew
the cadmium rod.
Fermi nodded and ZIP was winched out as well.
“is is
going to do it,” Fermi told Compton.
e director of the plutonium project
had found a place for himself at Fermi’s side.
“Now it will become self-
sustaining.
e trace [on the recorder] will climb and continue to climb; it
will not level off.” 1698
Herbert Anderson was an eyewitness:
At first you could hear the sound of the neutron counter, clickety-clack, clickety-clack.
en the
clicks came more and more rapidly, and aer a while they began to merge into a roar; the counter
couldn’t follow anymore.
at was the moment to switch to the chart recorder.
But when the
switch was made, everyone watched in the sudden silence the mounting deflection of the
recorder’s pen.
It was an awesome silence.
Everyone realized the significance of that switch; we
were in the high intensity regime and the counters were unable to cope with the situation anymore.
Again and again, the scale of the recorder had to be changed to accommodate the neutron
intensity which was increasing more and more rapidly.
Suddenly Fermi raised his hand.
“e pile
has gone critical,” he announced.
No one present had any doubt about it.1699
Fermi allowed himself a grin.
He would tell the technical council the next
day that the pile achieved a k of 1.0006.1700 Its neutron intensity was then
doubling every two minutes.
Le uncontrolled for an hour and a half, that
rate of increase would have carried it to a million kilowatts.
Long before so
extreme a runaway it would have killed anyone le in the room and melted
down.
“en everyone began to wonder why he didn’t shut the pile off,”
Anderson continues.
1701 “But Fermi was completely calm.
He waited
another minute, then another, and then when it seemed that the anxiety was
too much to bear, he ordered ‘ZIP in!’ ” It was 3:53 P.M.
Fermi had run the
pile for 4.5 minutes at one-half watt and brought to fruition all the years of
discovery and experiment.
Men had controlled the release of energy from
the atomic nucleus.
e chain reaction was moonshine no more.
Eugene Wigner reports how they felt:
Nothing very spectacular had happened.
Nothing had moved and the pile itself had given no
sound.
Nevertheless, when the rods were pushed back in and the clicking died down, we suddenly
experienced a let-down feeling, for all of us understood the language of the counter.
Even though
we had anticipated the success of the experiment, its accomplishment had a deep impact on us.
For
some time we had known that we were about to unlock a giant; still, we could not escape an eerie
feeling when we knew we had actually done it.
We felt as, I presume, everyone feels who has done
something that he knows will have very far-reaching consequences which he cannot foresee.
1702
Months earlier, realizing that the importation of Italian wine had been cut
off by the war, Wigner had searched the liquor stores of Chicago for a
celebratory fiasca of Chianti.
He produced it now in a brown paper bag and
presented it to Fermi.
“We each had a small amount in a paper cup,”
Wattenberg says, “and drank silently, looking at Fermi.
Someone told Fermi
to sign the [straw] wrapping on the bottle.
Aer he did so, he passed it
around, and we all signed it, except Wigner.” 1703
Compton and Greenewalt took their leave as Wilson began shutting down
the electronics.
Seaborg bumped into the Du Pont engineer in the corridor
of Eckhart Hall and found him “bursting with good news.
”1704 Back in his
office Compton called Conant, who was working in Washington “in my
quarters in the dormitory attached to the Dumbarton Oaks Library and
Collection of Harvard University.” 1705 Compton records their improvised
dialogue:
“Jim,” I said, “you’ll be interested to know that the Italian navigator has just landed in the new world.” en, half apologetically, because I had led the S-1 Committee to believe that it would be
another week or more before the pile could be completed, I added, “the earth was not as large as he
had estimated, and he arrived at the new world sooner than he had expected.” 1706
“Is that so,” was Conant’s excited response.
“Were the natives friendly?”
“Everyone landed safe and happy.”
Except Leo Szilard.
Szilard, who was responsible with Fermi for the
accomplishment that chill December aernoon of what he had first
imagined alone on a gray September morning in another country an age ago
—the old world undone by the new—loitered on the balcony, a small round
man in an overcoat.
He had dreamed that atomic energy might substitute
exploration for war, carrying men away from the narrow earth into the
cosmos.
He knew now that long before it propelled any such exodus it would
increase war’s devastation and mire man deeper in fear.
He blinked behind
his glasses.
It was the end of the beginning.
It might well be the beginning of
the end.
“ere was a crowd there and then Fermi and I stayed there alone.
I
shook hands with Fermi and I said I thought this day would go down as a
black day in the history of mankind.
”1707
14
Physics and Desert Country
Robert Oppenheimer was thirty-eight years old in 1942.
He had done by
then what Hans Bethe calls “massive scientific work.
”1708 He was known and
respected as a theoretician throughout the world of physics.
Up to the time
of the Berkeley summer study, however, few of his peers seem to have
thought him capable of decisive leadership.
ough he had matured deeply
across the decade of the 1930s, his persistent mannerisms, especially his
caustic tongue, may have screened his maturity from his colleagues’ eyes.
Yet
the 1930s shaped Oppenheimer for the work that was now to challenge him.
His distinctive appearance sharpens the memory of an admiring new
friend of that decade, a Berkeley professor and translator of French literature
named Haakon Chevalier:
[Oppenheimer] was tall, nervous and intent, and he moved with an odd gait, a kind of jog, with a
great deal of swinging of his limbs, his head always a little to one side, one shoulder higher than
the other.
But it was the head that was the most striking: the halo of wispy black curly hair, the fine,
sharp nose, and especially the eyes, surprisingly blue, having a strange depth and intensity, and yet
expressive of a candor that was altogether disarming.
He looked like a young Einstein, and at the
same time like an overgrown choir boy.
1709
Chevalier’s portrait identifies Oppenheimer’s youthfulness and sensitivity
but misses the self-destructiveness: the chain-smoking, the persistent cough
persistently ignored, the ravaged teeth, the usually empty stomach assaulted
by highly praised martinis and highly spiced food.
Oppenheimer’s
emaciation suggests he had an aversion to incorporating the world.
His body
embarrassed him and he seldom allowed himself to appear, as at the beach,
undressed.
At school he wore gray suits, blue shirts and well-polished black
shoes.
At home (a small spare apartment at first; later, aer his marriage, the
elegant house in the Berkeley hills he bought with a check the day he first
toured it) he preferred jeans and blue chambray work shirts, the jeans hung
on his narrow hips with a wide Western silver-buckled belt.
It was not a
common look in the 1930s—he had picked it up in New Mexico—and it was
another detail that made him seem different.
Women thought him handsome and dashing.
Before a party he might
send gardenias not only to his own date but to his friends’ dates as well.
“He
was great at a party,” a female acquaintance of his later adulthood comments,
“and women simply loved him.” 1710 His unfailing attentiveness probably
elicited that admiration: “He was always,” writes Chevalier, “without
seeming effort, aware of, and responsive to, everyone in the room, and was
constantly anticipating unspoken wishes.
”1711
Men he could antagonize or amuse.
Edward Teller first met Oppenheimer
in 1937.
e meeting, Teller says, was “painful but characteristic.
On the
evening I was to talk at a Berkeley colloquium, he took me out to a Mexican
restaurant for dinner.
I didn’t have the practice in speaking that I’ve had
since, and I was already a little nervous.
e plates were so hot, and the
spices were so hot—as you might suspect if you knew Oppenheimer—and
his personality was so overpowering, that I lost my voice.” 1712 Emilio Segrè
notes that Oppenheimer “sometimes appeared amateurish and snobbish.”
Out of curiosity in 1940, while visiting Berkeley to deliver a lecture, Enrico
Fermi attended a seminar one of Oppenheimer’s protégés led in the master’s
style.
“Emilio,” Fermi joked aerward with Segrè, “I am getting rusty and
old.
I cannot follow the highbrow theory developed by Oppenheimer’s
pupils anymore.
I went to their seminar and was depressed by my inability
to understand them.
Only the last sentence cheered me up; it was: ‘and this
is Fermi’s theory of beta decay.’ ” Although Segrè found Oppenheimer “the
fastest thinker I’ve ever met,” with “an iron memory...
brilliance and solid
merits,” he also saw “grave defects” including “occasional arrogance...
[that] stung scientific colleagues where they were most sensitive.” “Robert
could make people feel they were fools,” Bethe says simply.1713 “He made
me, but I didn’t mind.
Lawrence did.
e two disagreed while they were
both still at Berkeley.1714 I think Robert would give Lawrence a feeling that
he didn’t know physics, and since that is what cyclotrons are for, Lawrence
didn’t like it.” Oppenheimer recognized the habit without diagnosing it in a
letter to his younger brother Frank: “But it is not easy—at least it is not easy
for me—to be quite free of the desire to browbeat somebody or
something.” 1715 He called the behavior “beastliness.” It did not win him
friends.
Oppenheimer’s mother died aer a long battle with leukemia in late 1931;
that was when he announced himself to Herbert Smith, his former Ethical
Culture teacher, to be “the loneliest man in the world.
”1716 His father died suddenly of a heart attack in 1937.
e two deaths frame the beginning years
of the unworldly physicist’s discovery of the suffering in the world.
Later he
testified to the surprise of that discovery:
My friends, both in Pasadena and in Berkeley, were mostly faculty people, scientists, classicists,
and artists.
I studied and read Sanskrit with Arthur Ryder.
I read very widely, mostly classics, novels, plays, and poetry; and I read something of other parts of science.
I was not interested in
and did not read about economics or politics.
I was almost wholly divorced from the
contemporary scene in this country.
I never read a newspaper or a current magazine like Time or
Harper’s; I had no radio, no telephone; I learned of the stock market crash in the fall of 1929 only
long aer the event; the first time I ever voted was in the Presidential election of 1936.
1717, 1718 To many of my friends, my indifference to contemporary affairs seemed bizarre, and they oen chided
me with being too much of a highbrow.
I was interested in man and his experience; I was deeply
interested in my science; but I had no understanding of the relations of man to his society....
Beginning in late 1936, my interests began to change.
Oppenheimer reports three reasons for the change.
“I had had a
continuing, smouldering fury about the treatment of the Jews in Germany,”
he mentions first.
“I had relatives there, and was later to help in extricating
them and bringing them to this country.” ey arrived only a few days aer
his father’s death and he and Frank volunteered responsibility for them.
Second, says Oppenheimer, “I saw what the Depression was doing to my
students.” Philip Morrison, one of the wittiest of the young theoreticians,
polio-crippled and poor, remembers in compensation the “very grave, very
profound involvement in physics, the love of the whole thing, which we all
had in those days.” 1719 Oppenheimer could take his admiring students to
dinner; he was unable to find them jobs.
“And through them,” he testifies, “I
began to understand how deeply political and economic events could affect
men’s lives.
1720 I began to feel the need to participate more fully in the life of
the community.”
He had no framework yet.
A woman would help him with that, her
involvement the third reason he gives for his entry into the world: Jean
Tatlock, the lithe, chiaroscuro daughter of an anti-Semite Berkeley
medievalist.
“In the autumn [of 1936], I began to court her, and we grew
close to each other.
We were at least twice close enough to marriage to think
of ourselves as engaged.” Tatlock was bright, passionate and compassionate,
frequently depressed; their relationship was an ocean of storms.
But so were
Tatlock’s other commitments.
“She told me about her Communist Party
memberships; they were on again, off again affairs, and never seemed to
provide for her what she was seeking.” e couple began to move together
among what he calls “lewing friends....
I liked the new sense of
companionship, and at the time felt that I was coming to be part of the life of
my time and country.” 1721 He was taken with the causes of the Loyalists in
the Spanish Civil War and the migrant workers in California, to both of
which he contributed time and money.
He read Engels and Feuerbach and
all of Marx, finding their dialectics less rigorous than his taste: “I never
accepted Communist dogma or theory; in fact, it never made sense to
me”.
1722
He met his wife, Kitty, in the summer of 1939 in Pasadena.
She was petite
and dark, with a broad, high forehead, brown eyes, prominent cheekbones
and a wide, expressive mouth.
On the rebound she had married a young
British physician, “Dr.
[Stewart] Harrison, who was a friend and associate of
the [Richard] Tolmans, [Charles C.] Lauritsens, and others of the California
Institute of Technology faculty [Harrison was doing cancer research].
I
learned of her earlier marriage to Joe Dallet, and of his death fighting in
Spain.
He had been a Communist Party official, and for a year or two during
their brief marriage my wife was a Communist Party member.
When I met
her I found in her a deep loyalty to her former husband, a complete
disengagement from any political activity, and a certain disappointment and
contempt that the Communist Party was not in fact what she had once
thought it was.
”1723 e involvement was apparently immediate and intense.
Probably with his wife’s encouragement, but certainly with his own
growing good sense, Oppenheimer began to jettison political commitments
that had come to seem parochial.
“I went to a big Spanish relief party the
night before Pearl Harbor,” he testifies in example, “and the next day, as we
heard the news of the outbreak of war, I decided that I had had about
enough of the Spanish cause, and that there were other and more pressing
crises in the world.” 1724, 1725 He was willing similarly to abandon the American Association of Scientific Workers at Lawrence’s insistence in order
to help, as he supposed, to beat the Nazis to the atomic bomb.
By then, says Bethe, though Oppenheimer had been a poor teacher when
he began, pitching quantum theory well above his students’ untrained range,
he had “created the greatest school of theoretical physics that the United
States has ever known.” Bethe’s explanation for that evolution reveals the
seedbed of Oppenheimer’s later administrative leadership:
Probably the most important ingredient he brought to his teaching was his exquisite taste.
He
always knew what were the important problems, as shown by his choice of subjects.
He truly lived
with those problems, struggling for a solution, and he communicated his concern to his group....
He was interested in everything, and in one aernoon [he and his students] might discuss
quantum electrodynamics, cosmic rays, electron pair production and nuclear physics.
During the same period Oppenheimer’s clumsiness with experiment
evolved to appreciation and he consciously mastered experimental work—
hands off.
“He began to observe, not manipulate,” a former student notes.
“He learned to see the apparatus and to get a feeling of its experimental
limitations.
He grasped the underlying physics and had the best memory I
know of.
He could always see how far any particular experiment would go.
When you couldn’t carry it any farther, you could count on him to
understand and to be thinking about the next thing you might want to
try.
”1726
It remained for Oppenheimer to learn to control his “beastliness” and
submerge his mannerisms.
But he was always a quick study.
Significantly, he
was least convoluted, most direct, least mannered, most natural living
simply at his unadorned ranch in the Pecos Valley high in the Sangre de
Cristo Mountains of northern New Mexico.
Oppenheimer first met General Leslie R.
Groves when Groves came to
Berkeley from Chicago on his initial inspection tour early in October 1942.
ey attended a luncheon given by the president of the university; aerward
they talked.
Oppenheimer had already discussed the need for a fast-neutron
laboratory at the Met Lab technical council meeting on September 29.
1727
He envisioned more responsibilities for that laboratory than basic fission
studies, as he testified aer the war:
I became convinced, as did others, that a major change was called for in the work on the bomb
itself.
We needed a central laboratory devoted wholly to this purpose, where people could talk
freely with each other, where theoretical ideas and experimental findings could affect each other,
where the waste and frustration and error of the many compartmentalized experimental studies
could be eliminated, where we could begin to come to grips with chemical, metallurgical,
engineering, and ordnance problems that had so far received no consideration.1728
Memory compresses the laboratory’s evolution here, however; Oppenheimer
is not likely to have discussed eliminating Groves’ cherished
compartmentalization at their first meeting.
To the contrary, he goes on to
say, the two men first considered making the laboratory “a military
establishment in which key personnel would be commissioned as officers,”
and he carried the idea far enough before he le Berkeley to visit a nearby
military post to begin the process of commissioning.1729
Groves remembers that his “original impression gained from our first
conversation in Berkeley” was that a central laboratory was a good idea; he
felt strongly that “the work [of bomb design] should be started at once in
order that one part of our operation, at any rate, could progress at what I
hoped would be a comfortable pace.” 1730, 1731 His immediate concern was leadership; he believed that the right man at the helm could sail even the
most ungovernable boat.
Ernest Lawrence would have been Groves’ first
choice, but the general doubted if anyone else could make electromagnetic
isotope separation work.
Compton had his hands full in Chicago.
Harold
Urey was a chemist.
“Outside the project there may have been other suitable
people, but they were all fully occupied on essential work, and none of those
suggested appeared to be the equal of Oppenheimer.” 1732 Groves had already
sized up his man.
“It was not obvious that Oppenheimer would be [the new laboratory’s]
director,” Bethe notes.
“He had, aer all, no experience in directing a large
group of people.
e laboratory would be devoted primarily to experiment
and to engineering, and Oppenheimer was a theorist.
”1733 Worse—in the
eyes of the project leaders, Nobel laureates all—he had no Nobel Prize to
distinguish him.
ere was also what Groves calls the “snag” of
Oppenheimer’s le-wing background, which “included much that was not
to our liking by any means.
”1734 Groves had not yet wrested control of
Manhattan Project security from Army counterintelligence, and that
organization adamantly refused to clear someone whose former fiancée,
wife, brother and sister-in-law had all been members of the Communist
Party once and perhaps, gone underground, still were.
e general wanted Oppenheimer anyway.
“He’s a genius,” Groves told an
interviewer off the record immediately aer the war.
“A real genius.
While
Lawrence is very bright he’s not a genius, just a good hard worker.
Why,
Oppenheimer knows about everything.
He can talk to you about anything
you bring up.1735 Well, not exactly.
I guess there are a few things he doesn’t know about.
He doesn’t know anything about sports.”
Groves proposed Oppenheimer’s name to the Military Policy Committee.
It balked.
“Aer much discussion I asked each member to give me the name
of a man who would be a better choice.
In a few weeks it became apparent
that we were not going to find a better man; so Oppenheimer was asked to
undertake the task.
”1736 e physicist demurred later that he was chosen “by
default.
e truth is that the obvious people were already taken and that the
Project had a bad name.” 1737 Rabi would come to think that “it was a real
stroke of genius on the part of General Groves, who was not generally
considered to be a genius, to have appointed him,” but at the time it seemed
“a most improbable appointment.
I was astonished.
”1738 Groves on his way
from Chicago to New York asked Oppenheimer on October 15, 1942, to ride
on the train with him as far as Detroit to discuss the appointment.
e two
men met with Vannevar Bush in Washington on October 19.
1739 at long
meeting was apparently decisive.
Security questions would have to wait.
e next problem was where to locate the new laboratory.
Already at his
first meeting with Oppenheimer in Berkeley, Groves had stressed the need
for isolation; however much or little the scientists who gathered at the new
center would be allowed to talk to each other, the general intended to divide
them away from the populace.
“For this reason,” Oppenheimer wrote his
Illinois colleague John H.
Manley in mid-October, “some rather far reaching
geographical change in plans seems to be in the cards.” (In the same letter
Oppenheimer proposed “start[ing] now on a policy of absolutely
unscrupulous recruiting of anyone we can lay hands on.
”1740, 1741 He wanted the best he could get, and soon asked Groves for the likes of Bethe, Segrè,
Serber and Teller.)
Site Y, as the hypothetical laboratory was initially called, needed good
transportation, an adequate supply of water, a local labor force and a
moderate climate for year-round construction and for experiment
conducted outdoors.
In his memoirs Groves lists safety as the primary
reason he insisted on isolation—“so that nearby communities would not be
adversely affected by any unforeseen results from our activities”—but the
high steel fence topped with triple strands of barbed wire that eventually
surrounded the laboratory was clearly not designed to confine explosions.
Groves was in the midst of selecting sites for Manhattan Project production
centers; the difference between his criteria for those locations and his
criteria for Site Y was that at the bomb-design laboratory “we were faced
with the necessity of importing a group of highly talented specialists, some
of whom would be prima donnas, and of keeping them satisfied with their
working and living conditions.
”1742 If that in fact was Groves’ intention, it
was one of the few wartime goals he failed to achieve.
1743
e general assigned the task of identifying a suitable location for the
laboratory to Major John H.
Dudley of the Manhattan Engineer District.
Groves gave Dudley criteria more specific than satisfying prima donnas:
room for 265 people, location at least two hundred miles from any
international boundary but west of the Mississippi, some existing facilities, a
natural bowl with the hills nearby that shaped the bowl so that fences might
be strung on top and guarded.
Traveling by air, rail, auto, jeep and horse
through most of the American Southwest, Dudley found the perfect place:
Oak City, Utah, “a delightful little oasis in south central Utah.
”1744 But to claim it the Army would have had to evict several dozen families and
remove a large area of farmland from production.
Dudley thereupon
recommended his second choice: Jemez Springs, New Mexico, a deep
canyon about forty miles northwest of Santa Fe on the western slope of the
Jemez Mountains—“a lovely spot,” Oppenheimer thought in early November
before he toured it, “and in every way satisfactory.
”1745
When the newly appointed director arrived on November 16 to inspect
the Jemez Springs location with Dudley and Edwin McMillan, who was
helping start the laboratory, he changed his mind.
e canyon felt confining;
Oppenheimer knew the region’s grand scenic vistas and decided he wanted a
laboratory with a view.
McMillan also remembers expressing “considerable
reservations about this site” :1746
We were arguing [with Dudley] when General Groves showed up.
is had been planned.
He
would come in sometime in the aernoon and receive our report.
As soon as Groves saw the site
he didn’t like it; he said, “is will never do.”...
At that point Oppenheimer spoke up and said “if
you go on up the canyon you come out on top of the mesa and there’s a boys’ school there which
might be a usable site.”
Oppenheimer proposed the boys’ school site, grouses Dudley, “as though it
was a brand new idea.” Dudley had already scouted the mesa twice, rejecting
it because it failed to meet Groves’ criteria.
But a mesa is an inverted bowl,
its perimeter similarly fencible.
And the first requirement was to make the
longhairs happy.
“As I...
knew the roads (or trails),” Dudley says
sardonically, “...
we drove directly there.” 1747
“e school was called Los Alamos,” the daughter of its founder writes,
“aer the deep canyon which bordered the mesa to the south and which was
groved with cottonwood trees along the sandy trickle of its stream.” 1748
Ashley Pond, the founder, had been a sickly boarding-school boy sent West
for his health, like Oppenheimer, who returned to New Mexico in later
adulthood when his father died and le him with independent means.
He
opened the Los Alamos Ranch School on the 7,200-foot mesa in 1917.
It was
organized to invigorate pale scions, as Pond had been invigorated: boys slept
on unheated porches of a chinked-log dormitory and wore shorts in winter
snow; each was assigned a horse to ride and groom.
It was, Emilio Segrè
writes, “beautiful and savage country”: the dark Jemez Mountains to the
west that formed the higher rim of the Jemez Caldera, the slumped cone of
the old volcano of which Los Alamos was eroded tuffaceous spill;
precipitously down from the mesa eastward the valley of the Rio Grande,
“hot and barren” except for the green meander of the river, writes Laura
Fermi, with “sand, cacti, a few piñon trees hardly rising above the ground,
and space, immense, transparent, with no fog or moisture”; farther east the
wall of the Rocky Mountains as that range extends south into New Mexico
to form the Sangre de Cristo, reversing hue from green to red progressively
at sunset.1749 , 1750 “I remember arriving [at Los Alamos],” McMillan continues of that first inspection, “and it was late in the aernoon.
ere was
a slight snow falling....
It was cold and there were the boys and their
masters out on the playing fields in shorts.
I remarked that they really
believed in hardening up the youth.
As soon as Groves saw it, he said, in
effect, ‘is is the place.’ ”1751
“My two great loves are physics and desert country,” Robert Oppenheimer
had written a friend once; “it’s a pity they can’t be combined.” 1752 Now they
would be.
Leo Szilard, urban man, habitué of hotel lobbies, took a different view of
the location when he heard about it.
“Nobody could think straight in a place
like that,” he told his Met Lab colleagues.
“Everybody who goes there will go
crazy.
”1753 e Corps of Engineers’ appraisal prepared on November 21
describes a large forested site thirty-five miles by road northwest of Santa Fe
with no gas or oil lines, one one-wire Forest Service telephone, average
annual precipitation of 18.53 inches and an annual range of temperatures
from —12° to 92°F.
1754 e land and improvements, including the boys’
school with its sixty horses, two tractors, two trucks, fiy saddles, eight
hundred cords of firewood, twenty-five tons of coal and sixteen hundred
books, were worth $440,000.
e school was willing to sell.
e Manhattan
Project acquired its scenic laboratory site.
Groves convinced the University of California to serve as contractor to
operate the secret installation.
Construction—of cheap, barracks-like
buildings not intended to outlast the war, with coal-burning stoves and no
sidewalks on which to escape the mire of spring and autumn mud—began
almost immediately.
“What we were trying to do,” writes John Manley, the
University of Illinois physicist working with Oppenheimer then, “was build
a new laboratory in the wilds of New Mexico with no initial equipment
except the library of Horatio Alger books or whatever it was that those boys
in the Ranch School read, and the pack equipment that they used going
horseback riding, none of which helped us very much in getting neutron-
producing accelerators.” 1755 Robert R.
Wilson, a young Berkeley Ph.D.
teaching at Princeton, went up to Harvard for Oppenheimer and negotiated
with Percy Bridgman for the Harvard cyclotron; Wisconsin would
contribute two Van de Graaffs; from other laboratories, including Berkeley
and the University of Illinois, Manley scavenged other gear.
In the meantime
Oppenheimer crisscrossed the country recruiting:
e prospect of coming to Los Alamos aroused great misgivings.
1756 It was to be a military post; men were asked to sign up more or less for the duration; restrictions on travel and on the freedom
of families to move about would be severe....
e notion of disappearing into the New Mexico
desert for an indeterminate period and under quasi-military auspices disturbed a good many
scientists, and the families of many more.
But there was another side to it.
Almost everyone
realized that this was a great undertaking.
Almost everyone knew that if it were completed
successfully and rapidly enough, it might determine the outcome of the war.
Almost everyone
knew that it was an unparalleled opportunity to bring to bear the basic knowledge and art of
science for the benefit of his country.
Almost everyone knew that this job, if it were achieved, would be a part of history.
is sense of excitement, of devotion and of patriotism in the end
prevailed.
Most of those with whom I talked came to Los Alamos.
One of the most tough-minded, I.
I.
Rabi, did not.
His reasons are
revealing.
He continued developing radar at the Radiation Laboratory at
MIT.
“Oppenheimer wanted me to be the associate director,” he told an
interviewer many years later.
“I thought it over and turned him down.
I said,
‘I’m very serious about this war.
We could lose it with insufficient
radar.’ ”1757 e Columbia physicist thought radar more immediately
important to the defense of his country than the distant prospect of an
atomic bomb.
Nor did he choose to work full time, he told Oppenheimer, to
make “the culmination of three centuries of physics” a weapon of mass
destruction.
1758 Oppenheimer responded that he would take “a different
stand” if he thought the atomic bomb would serve as such a culmination.
“To me it is primarily the development in time of war of a military weapon
of some consequence.
”1759 Either Oppenheimer had not yet thought his way
through to a more millenarian view of the new weapon’s implications or he
chose to avoid discussing those implications with Rabi.
He asked Rabi only
to participate in an inaugural physics conference at Los Alamos in April
1943 and to help convince others, particularly Hans Bethe, to sign on.
Eventually Rabi would come and go as a visiting consultant, one of the very
few exceptions to Groves’ compartmentalization and isolation rules.
Oppenheimer talked to the Bethes in Cambridge in snowy New England
December; they questioned him at length about the life they would be asked
to lead.
Extracts from his letter of response sketch the invention of an
instant community: “Laboratory...
town...
utilities, schools, hospitals...
a sort of city manager...
city engineer...
teachers...
M.P.
camp...
a
laundry...
two eating places...
a recreation officer...
libraries, pack trips,
movies...
bachelor apartments...
a so-called Post Exchange...
a vet...
barbers and such like...
a cantina where we can have beer and cokes and
light lunches.” e Bethes’ best guarantee of satisfaction, Oppenheimer
concluded, “is in the great effort and generosity that...
Groves [has]
brought to setting up this odd community and in [Groves’] evident desire to
make a real success of it.
In general [he is] not interested in saving money,
but...
in saving critical materials, in cutting down personnel, and in doing
nothing which would attract Congressional attention to our hi-jinks.” He
chose not to mention the security arrangements, in the development of
which he was participating: the perimeter fence, the pass controls, the
virtual elimination of telephones (“Oppenheimer’s idea was one telephone
for himself,” says Dudley, “one for the post commander, and any volume
business would go out over a teletype.
”1760, 1761 ).
By March Teller found
Bethe taking “a very optimistic view, and there was no need whatever to
persuade him to come.
”1762
Teller felt underemployed in Chicago and was eager to move to the new
laboratory.
John Manley asked him to write a prospectus to help with
recruiting, which Teller sent to Oppenheimer in early January.
During the
Berkeley summer study the two men had begun what another participant
judged a “mental love affair.” 1763, 1764 Teller “liked and respected Oppie enormously.
He kept wanting to talk about him with others who knew him,
kept bringing up his name in conversation.” Bethe noticed then and later
that despite their many outward differences Teller and Oppenheimer were
“fundamentally...
very similar.1765 Teller had an extremely quick
understanding of things, so did Oppenheimer....
ey were also somewhat
alike in that their actual production, their scientific publications, did not
measure up in any way to their capacity.
I think Teller’s mental capacity is
very high, and so was Oppenheimer’s but, on the other hand, their papers,
while they included some very good ones, never reached really the top
standards.
Neither of them ever came up to the Nobel Prize level.
I think
you just cannot get to that level unless you are somewhat introverted.” (Luis
Alvarez, the 1968 physics Nobel laureate, disagrees, at least where
Oppenheimer is concerned.
1766 He believes Oppenheimer would have won a
Nobel Prize for his astrophysical work if he had lived long enough to see his
predictions concerning exotic stellar objects—neutron stars, black holes—
confirmed, as they have been, by discovery.) Both Oppenheimer and Teller
wrote poetry; Oppenheimer pursued literature as Teller pursued music; and
for a time in 1942 and 1943 the Hungarian apparently admired the older and
socially more sophisticated New Yorker and hoped to count him for an ally.
As Oppenheimer traveled the country recruiting he discovered to his
surprise that few of his colleagues were attracted to the notion of joining the
Army.
It fell to Rabi and his Rad Lab colleague Robert F.
Bacher, during the
weeks before Rabi decided to stay in Cambridge, to lead the revolt.
e
necessity of “scientific autonomy” was one crucial reason they cited for
resisting militarization, Oppenheimer wrote Conant at the beginning of
February 1943, and they insisted as a corollary that although “the execution
of the security and secrecy measures should be in the hands of the
military...
the decision as to what measures should be applied must be in
the hands of the Laboratory.” On that point Oppenheimer concurred,
“because I believe it is the only way to assure the cooperation and the
unimpaired morale of the scientists.” e stakes were higher than simply
losing Rabi and Bacher, Oppenheimer told Conant: “I believe that the
solidarity of physicists is such that if these conditions are not met, we shall
not only fail to have the men from M.I.T with us, but that many men who
have already planned to join the new Laboratory will reconsider their
commitments or come with such misgivings as to reduce their usefulness.” A
rebellion, he concluded, would mean “a real delay in our work.” 1767
Groves had wanted the scientists commissioned as a security measure and
because their work might be hazardous.
He was hardly interested in the
politics of the question, but delay was unthinkable.
He compromised.
Conant wrote a letter, co-signed by Groves, that Oppenheimer could use in
recruiting; it allowed the new laboratory civilian administration and civilian
staff until the time of hazardous large-scale trials.
en anyone who wanted
to stay would have to accept a commission (a provision Groves chose later
not to pursue).
e Army would administer the community it was building
around the laboratory.
Laboratory security would be Oppenheimer’s
responsibility, and he would report to Groves.
Robert Oppenheimer thus acquired for Los Alamos what Leo Szilard had
not been able to organize in Chicago: scientific freedom of speech.
e price
the new community paid, a social but more profoundly a political price, was
a guarded barbed-wire fence around the town and a second guarded
barbed-wire fence around the laboratory itself, emphasizing that the
scientists and their families were walled off where knowledge of their work
was concerned not only from the world but even from each other.
“Several
of the European-born were unhappy,” Laura Fermi notes, “because living
inside a fenced area reminded them of concentration camps.” 1768
* * *
e heavy-water installation at Vemork in southern Norway became a target
of British sabotage operations in the winter of 1942–43.
e British had
been planning to send in two glider-loads of demolition experts, thirty-four
trained volunteers; when Groves requested Allied action soon aer his
appointment to administer the Manhattan Project they moved ahead to
comply.
An advance party of four Norwegian commandos parachuted into
the Rjukan area on October 18 to prepare the way, but bad planning and bad
weather brought disaster to the gliders on the night of November 19 when
they crossed the North Sea from Scotland; both crashed in Norway, one into
a mountainside, and the fourteen men who survived the separate disasters
were captured by German occupation forces and executed the same day.
R.
V.
Jones, an Oxford protégé of Cherwell who was now director of
intelligence for the British Air Staff, then had “one of the most painful
decisions that I had to make” —whether to send another demolition party
aer the first.
“I reasoned that we had already decided, before the tragedy of
the first raid and therefore free from sentiment, that the heavy water plant
must be destroyed; casualties must be expected in war, and so if we were
right in asking for the first raid we were probably right in asking that it be
repeated.”
is time six men, Norwegians native to the region and trained as Special
Forces, parachuted onto a frozen lake thirty miles northwest of Vemork on
February 16, 1943, the night of a full moon.
1769 “Here lay the Hardanger
Vidda,” one of them, Knut Haukelid, writes of the high plateau that
surrounded the lake, “the largest, loneliest and wildest mountain area in
northern Europe.” e men wore white jumpsuits over British Army
uniforms and parachuted with skis, supplies, a shortwave radio and eighteen
sets of plastic explosives, one for each of the eighteen stainless-steel
electrolysis cells of the High Concentration Plant—which happened to have
been designed by a refugee physical chemist, Lief Tronstad, who was now
responsible to the Norwegian High Command in London for intelligence
and sabotage.
Haukelid, a powerfully built mountaineer, says they weathered
“one of the worst storms I have ever experienced in the mountains” to
rendezvous some days later with the four Norwegians of the original
advance party, who had been forced to hide out on the barren Hardanger
Vidda and were malnourished and weak.
1770, 1771, 1772 e new arrivals fattened up their compatriots while one of them skied on to Rjukan to
gather the latest information about the plant.
He returned to report
minefields laid around the obvious approaches, guards on the suspension
bridge that crossed the sheer gorge above the shelf on which the
hydrochemical facility was built but only fieen German soldiers on duty
despite the forewarning of the failed glider attack.
e factory itself was
fitted with searchlights and guarded with machine guns.
e commandos set out mid-evening on Saturday, February 27, leaving
one man behind to guard the radios.
ey carried cyanide capsules and
agreed that if anyone was wounded he would take his own life rather than
allow himself to be captured and risk betraying his comrades.
ey had
camped high on the mountain across the gorge from the plant, which was
located to take advantage of the fall of water from the lake that fed it,
Tinnsjö.
“Halfway down we sighted our objective for the first time, below us
on the other side.
e great seven-storey factory building bulked large on
the landscape....
[e wind] was blowing fairly hard, but nevertheless the
hum of the machinery came up to us through the ravine.
We understood
how the Germans could allow themselves to keep so small a guard there.
e colossus lay like a mediaeval castle, built in the most inaccessible place,
protected by precipices and rivers.” 1773
ey crashed down through so snow all the way to the bottom of the
gorge, crossed the frozen river, climbed up toward the plant on the other
side.
Above at the elevation of the shelf was a seldom-used railroad siding
leading into the compound that they hoped the Germans had chosen not to
mine.
“It was a dark night and there was no moon,” Haukelid remembers.
e searchlights were kept turned off and the high wind “drowned all the
noise we made.
Half an hour before midnight we came to a snow-covered
building five hundred yards from Vemork, where we ate a little chocolate
and waited for the change of sentries.” 1774 ey divided into two groups, a
demolition party and a covering party.
“We were well armed: five tommy-
guns among nine men, and everyone had a pistol, a knife and hand
grenades.” 1775
In an hour, time for the sentries to settle, they attacked.
Haukelid in the
covering party led the way.
With bolt cutters they snipped “the thin little
iron chain which barred the way to one of the most important military
objectives in Europe.
”1776 e covering party dispersed to its prearranged
positions—Haukelid and one other man took up posts twenty yards from
the Wehrmacht barracks, a flimsy wooden building they saw they could
easily shoot through—and the demolition party moved ahead.
e doors on
the ground floor of the plant were locked, but Tronstad in London had
identified for the commandos a cable intake that they could crawl along that
led directly to the heavy-water facility.
Two men looked for some other
entrance while two disappeared into the cable intake.
Aer what seemed to Haukelid an interminable delay he heard an
explosion, “but an astonishingly small, insignificant one.
Was this what we
had come over a thousand miles to do?” e guards were slow to check; only
one German soldier appeared and seemed not to realize what had happened;
he tried the doors to the plant, found them locked, looked to see if snow
falling from the mountain above had detonated a land mine and returned to
his quarters.1777 e Norwegians moved out fast.
ey had descended to the
river before the sirens began to sound.
e operation was successful.
No one was injured on either side.
All
eighteen cells had been blown open, spilling nearly half a ton of heavy water
into the drains.
Not only would the plant require weeks to repair; because it
was a cascade, pumping water of increasing deuterium concentration from
one cell to the next, it would need almost a year of operation aer repair
simply to reach equilibrium again on its own and begin producing.
General
Nikolaus von Falkenhorst, the commander in chief of the occupying
German Army in Norway, called the Vemork attack “the best coup I have
ever seen.
”1778 Whatever German physicists might be doing with heavy
water, they would do it more slowly now.
* * *
In Japan both the Army Air Force and the Imperial Navy had moved
separately since 1941 to promote atomic bomb research.1779 e Riken,
Yoshio Nishina’s prestigious Tokyo laboratory, primarily served the Army,
exploring the theoretical possibilities of U235 separation by way of the
gaseous barrier diffusion, gaseous thermal diffusion, electromagnetic and
centrifuge processes.
In the spring of 1942 the Navy committed itself to
developing nuclear power for propulsion:
e study of nuclear physics is a national project.
1780 Research in this field is continuing on a broad scale in the United States, which has recently obtained the services of a number of Jewish
scientists, and considerable progress has been made.
e objective is the creation of tremendous
amounts of energy through nuclear fission.
Should this research prove successful, it would provide
a stupendous and dependable source of power which could be used to activate ships and other
large pieces of machinery.
Although it is not expected that nuclear energy will be realized in the
near future, the possibility of it must not be ignored.
e Imperial Navy, accordingly, hereby
affirms its determination to foster and assist studies in this field.
Soon aer that nonviolent affirmation, however, the Naval Technological
Research Institute appointed a secret committee of leading Japanese
scientists—corresponding to the U.S.
National Academy of Sciences
committee—to meet monthly to follow research progress until it could
report decisively for or against a Japanese atomic bomb.
e committee
included Nishina, who was forthwith elected chairman.
An elderly
appointee was Hantarō Nagaoka, whose Saturnian atomic model had nearly
anticipated Ernest Rutherford’s planetary model in the early years of the
century.
e Navy committee met first on July 8 with the Navy’s chief technical
officers at an officers’ club at Shiba Park in Tokyo.
It noted that the United
States was probably working on a bomb and agreed that whether and how
soon Japan could produce such a weapon was as yet uncertain.
To the task of
answering those questions the Navy appropriated 2,000 yen, about $4,700,
somewhat less than the Uranium Committee had summoned from the U.S.
Treasury at Edward Teller’s request at the beginning of the American
program in 1939.
Nishina hardly participated in the Navy committee meetings.
e fact that
he was already working for the Army probably constrained him; the two
services, both of which were responsible directly to the Emperor without
detour through the civilian government, operated far more independently
than their American counterparts and were increasingly bitter rivals.
Nishina was coming to conclusions of his own, however, and at the end of
1942, when the Navy committee began to report discouragement, he met
privately with a young cosmic-ray physicist in his laboratory, Tadashi
Takeuchi, told his young colleague he meant to carry forward isotope
separation studies and asked him to help.
Takeuchi agreed.
Between December 1942 and March 1943 the Navy committee organized
a ten-session physics colloquium to work through to a decision.
By then it
was understood that a bomb would necessitate locating, mining and
processing hundreds of tons of uranium ore and that U235 separation would
require a tenth of the annual Japanese electrical capacity and half the nation’s
copper output.
e colloquium concluded that while an atomic bomb was
certainly possible, Japan might need ten years to build one.
e scientists
believed that neither Germany nor the United States had sufficient spare
industrial capacity to produce atomic bombs in time to be of use in the war.
Aer the final March 6 meeting the Navy representative at the colloquium
reported discouragement: “e best minds of Japan, studying the subject
from the point of view of their respective fields of endeavor as well as from
that of national defense, came to a conclusion that can only be regarded as
correct.
e more they considered and discussed the problem, the more
pessimistic became the atmosphere of the meeting.” 1781 As a result the Navy
dissolved the committee and asked its members to devote themselves to
more immediately valuable research, particularly radar.
Nishina continued isotope studies for the Army, deciding on March 19 to
focus on thermal diffusion as the only practical separation technology at a
time of increasing national shortages.
He spoke to his staff of processing
several hundred tons of uranium aer first building laboratory-scale
diffusion apparatus.
He envisioned a major program run in parallel, as the
Manhattan Project was beginning to be, with weapon design and
development proceeding simultaneously with U235 production.
Meanwhile a different branch of the Navy, the Fleet Administration
Center, sponsored a new project in atomic bomb development at the
University of Kyoto, where Tokutaro Hagiwara had made his startling early
prediction of the possibility of a thermonuclear explosive.
e university
won support in 1943 to the extent of 600,000 yen—nearly $1.5 million—
much of which it budgeted to build a cyclotron.
* * *
Robert Oppenheimer moved to Santa Fe with a small team of aides on
March 15, 1943, brisk early spring.
Scientists and their families arrived by
automobile and train during the next four weeks.
Not much was ready on
the mesa, which they began to call the Hill.
Groves wanted no breaches of
security in the lobbies of Santa Fe hotels; the Army commandeered guest
ranches in the area for quarters suitably remote and bought up Santa Fe’s
feeble stock of used cars and jitneys to serve as transportation through ruts
and mud up and down the terrifying unbarricaded dirt switchback of the
mesa access road.
Aer flat tires and mirings, hours could be short on the
Hill.
Box lunches assembled in Santa Fe gave cold comfort when the delivery
truck made it through.
e hardships only mattered because they slowed the work.
Oppenheimer
had sold it as work that would end the war to end all wars and his people
believed him.
e unit of measurement for wasted hours was therefore
human lives.
Construction crews unwilling to vary the specifications of a
laboratory door or hang an unauthorized shelf initially bore the brunt of the
scientists’ impatience.
John Manley remembers inspecting the chemistry
and physics building.
It needed a basement at one end for an accelerator and
a solid foundation at the other end for the two Van de Graaffs—which end
for which was unimportant.
Rather than adjust the construction plans for
terrain the contractor had drilled the basement from solid rock and used the
rock debris as fill for the foundation.
“is was my introduction to the Army
Engineers.
”1782
Fuller Lodge, a Ranch School hall elegantly assembled of monumental
hand-hewn logs, was kept to serve as a dining room and guest house.
e
pond south of the lodge—predictably named Ashley Pond aer the Ranch
School’s founder—offered winter ice-skating and summer canoeing and the
easeful harmonic wakes of swimming ducks.
e engineers preserved the
stone icehouse beside the pond that the school had used to store winter
cuttings of ice and the row of tree-shaded faculty residences northeast of the
lodge.
Across the dirt main road that divided the mesa south of the pond the
Tech Area went up in a style the Army called modified mobilization: plain
one-story buildings like elongated barracks with clapboard sides and
shingled roofs.
T Building would house Oppenheimer and his staff and the
eoretical Physics Division; behind T, connected by a covered walkway,
would be the much longer chemistry and physics building with its Van de
Graaffs; behind that the laboratory shops.
Farther south near the rim of the
mesa above Los Alamos canyon contractors would hammer up a cryogenics
laboratory and the building that would shelter Harvard’s cyclotron.
West and
north of the Tech Area the first two-story, four-unit family apartments,
painted drab green, urbanized last year’s pastures and fields; more
apartments, and dormitories for the unmarried, would follow.
At the beginning of April Oppenheimer assembled the scientific staff
—“about thirty persons” at that point of the hundred scientists initially
hired, says Emilio Segrè, who was one among them—for a series of
introductory lectures.
1783 Robert Serber, thin and shy, delivered the lectures
with authority despite the distraction of a lisp; they summed up the
conclusions of the Berkeley summer study and incorporated the
experimental fast-fission work of the past year.
Edward U.
Condon, the
crew-cut, Alamogordoborn theoretician from Westinghouse whom
Oppenheimer had chosen for associate director, revised his notes of Serber’s
lectures into the new laboratory’s first report, a document called the Los
Alamos Primer that was subsequently handed to all new Tech Area arrivals
cleared for Secret Limited access.
1784 In twenty-four mimeographed pages
the Primer defined the laboratory’s program to build the first atomic bombs.
Serber’s lectures startled the chemists and experimental physicists whom
compartmentalization had kept in the dark; the scientists’ euphoria at finally
learning in detail what they had only previously guessed or heard hinted
measures the extent to which secrecy had contorted their emotional
commitment to the work.
Now, following the lead of their mentors—their
average age was twenty-five; Oppenheimer, Bethe, Teller, McMillan, Bacher,
Segrè and Condon were older men—they could apply themselves at last with
devotion.
In that heady new freedom they seldom noticed the barbed wire.
Similarly confined but kept uninformed because Oppenheimer and Groves
decided it so, the wives served harder time.
“e object of the project,” Condon summarizes what Serber told the
scientists, “is to produce a practical military weapon in the form of a bomb
in which the energy is released by a fast neutron chain reaction in one or
more of the materials known to show nuclear fission.” 1785 Serber said one
kilogram of U235 was approximately equal to 20,000 tons of TNT and noted
that nature had almost located that conversion beyond human meddling:
“Since only the last few generations [of the chain reaction] will release
enough energy to produce much expansion [of the critical mass], it is just
possible for the reaction to occur to an interesting extent before it is stopped
by the spreading of the active material.” 1786 If fission had proceeded more
energetically the bombs would have slept forever in the dark beds of their
ores.
Serber discussed fission cross sections, the energy spectrum of secondary
neutrons, the average number of secondary neutrons per fission (measured
by then to be about 2.2 ), the neutron capture process in U238 that led to
plutonium and why ordinary uranium is safe (it would have to be enriched
to at least 7 percent U235, the young theoretician pointed out, “to make an
explosive reaction possible”).1787, 1788 He was already calling the bomb “the
gadget,” its nickname thereaer on the Hill, a bravado metonymy that
Oppenheimer probably coined.
1789 e calculations Serber reported
indicated a critical mass for metallic U235 tamped with a thick shell of
ordinary uranium of 15 kilograms: 33 pounds.
For plutonium similarly
tamped the critical mass might be 5 kilograms: 11 pounds.
e heart of their
atomic bomb would then be a cantaloupe of U235 or an orange of Pu239
surrounded by a watermelon of ordinary uranium tamper, the combined
diameter of the two nested spheres about 18 inches.
Shaped of such heavy
metal the tamper would weigh about a ton.
e critical masses would
eventually have to be determined by actual test, Serber said.
He went on to speak of damage.
Out to a radius of a thousand yards
around the point of explosion the area would be drenched with neutrons,
enough to produce “severe pathological effects.” 1790 at would render the
area uninhabitable for a time.
It was clear by now—it had not been clear
before—that a nuclear explosion would be no less damaging than an
equivalent chemical explosion.
“Since the one factor that determines the
damage is the energy release, our aim is simply to get as much energy from
the explosion as we can.
And since the materials we use are very precious,
we are constrained to do this with as high an efficiency as is possible.” 1791
Efficiency appeared to be a serious problem.
“e reaction will not go to
completion in an actual gadget.” 1792 Untamped, a bomb core even as large as
twice the critical mass would completely fission less than 1 percent of its
nuclear material before it expanded enough to stop the chain reaction from
proceeding.
An equally disadvantageous secondary effect also tended to stop
the reaction: “as the pressure builds up it begins to blow off material at the
outer edge of the [core].” 1793 Tamper always increased efficiency; it reflected
neutrons back into the core and its inertia—not its tensile strength, which
was inconsequential at the pressures a chain reaction would generate—
slowed the core’s expansion and helped keep the core surface from blowing
away.
But even with a good tamper they would need more than one critical
mass per bomb for reasonable efficiency.
Detonation was equally a problem.
To detonate their bombs they would
have to rearrange the core material so that its effective neutron number,
which corresponded to Fermi’s k, changed from less than 1 to more than 1.
But however they rearranged the material—firing one subcritical piece into
another subcritical piece inside the barrel of a cannon seemed to be the
simplest option—they would have no slow, smooth transition as Fermi had
with CP-1.
If they fired one piece into another at the high velocity of 3,000
feet per second it would take the pieces about a thousandth of a second to
assemble themselves.
But since more than one critical mass was necessary
for an efficient explosion the pieces would be supercritical before they had
completely mated.
If a stray neutron then started a chain reaction, the
resulting inefficient explosion would proceed from beginning to end in a few
millionths of a second.
“An explosion started by a premature neutron will be
all finished before there is time for the pieces to move an appreciable
distance.
”1794 Which meant that the neutron background—spontaneous-
fission neutrons from the tamper, neutrons knocked from light-element
impurities, neutrons from cosmic rays—would have to be kept as low as
possible and the rearrangement of the core material managed as fast as
possible.
On the other hand, they did not have to worry that a fizzle would
drop an intact bomb into enemy hands; even a fizzle would release energy
equivalent to at least sixty tons of TNT.
Predetonation would reduce the bomb’s efficiency, Serber repeated; so also
might postdetonation.
“When the pieces reach their best position we want to
be very sure that a neutron starts the reaction before the pieces have a
chance to separate and break.
”1795 So there might be a third basic
component to their atomic bomb besides nuclear core and confining
tamper: an initiator—a Ra + Be source or, better, a Po + Be source, with the
radium or polonium attached perhaps to one piece of the core and the
beryllium to the other, to smash together and spray neutrons when the parts
mated to start the chain reaction.
Firing the pieces of core together, the Berkeley theoretician continued, “is
the part of the job about which we know least at present.
”1796 e summer-
study group had examined several ingenious designs.
e most favorable
fired a cylindrical male plug of core and tamper into a mated female sphere
of tamper and core, illustrated here in cross section from the Los Alamos
Primer:
e target sphere could be simply welded to the muzzle of a cannon; then
the cylinder, which might weigh about a hundred pounds, could be fired up
the barrel like a shell:
e highest muzzle velocity available in U.S.
Army guns is one whose bore is 4.7 inches and whose
barrel is 21 feet long.
is gives a 50 lb.
projectile a muzzle velocity of 3150 /sec.
e gun weighs
5 tons.
It appears that the ratio of projectile mass to gun mass is about constant for different guns
so a 100 lb.
projectile would require a gun weighing about 10 tons.1798
For a mechanism eight times lighter or with double the effective muzzle
velocity they could weld two guns together at their muzzles and fire two
projectiles into each other.
Synchronization would be a problem with such a
design and efficiency might require four critical masses instead of two, a
demand which would significantly delay delivering a usable bomb.
Serber also described more speculative arrangements: sliced ellipsoidal
core-tamper assemblies like halves of hard-boiled eggs that slid together;
wedge-shaped quarters of core/tamper like sections of a quartered apple
mounted on a ring.
at was an odd and striking design, sketched in the
mimeographed Primer as probably on a blackboard before, and it did not go
unnoticed.
“If explosive material were distributed around the ring and fired
the pieces would be blown inward to form a sphere”:1799
Autocatalytic bombs—bombs in which the chain reaction itself, as it
proceeded, increased the neutron number for a time—looked less
promising.
e cleverest notion incorporated “bubbles” of boron-coated
paraffin into the U235 core; as the core expanded it would compress the
neutron-absorbing boron and render it less efficient, freeing more neutrons
for fission chains.
But: “All autocatalytic schemes that have been thought of
so far require large amounts of active material, are low in efficiency unless
very large amounts are used, and are dangerous to handle.
Some bright ideas
are needed.” 1801
eir immediate work of experiment, Serber concluded, would be
measuring the neutron properties of various materials and mastering the
ordnance problem—the problem, that is, of assembling a critical mass and
firing the bomb.
ey would also have to devise a way to measure a critical
mass for fast fission with subcritical amounts of U235 and Pu239.
ey had
a deadline: workable bombs ready when enough uranium and plutonium
was ready.
at probably gave them two years.
e Japanese physics colloquium in Tokyo had decided in March 1943
that an atomic bomb was possible but not practically attainable by any of the
belligerents in time to be of use in the present war.
Robert Serber’s lectures
at Los Alamos in early April asserted to the contrary that for the United
States an atomic bomb was both possible and probably attainable within two
years.
e Japanese assessment was essentially technological.
Like Bohr’s
assessment in 1939, it overestimated the difficulty of isotope separation and
underestimated U.S.
industrial capacity.
It also, as the Japanese government
had before Pearl Harbor, underestimated American dedication.
Collective
dedication was a pattern of Japanese culture more than of American.
But
Americans could summon it when challenged, and couple it with resources
of talent and capital unmatched anywhere else in the world.
e Europeans at Los Alamos complained of the barbed wire.
With the
exception, apparently, only of Edward Condon, who found security so
oppressive he quit the project within weeks of his arrival and went back to
Westinghouse, the Americans accepted the fences around their work and
their lives as a necessity of war.
e war was a manifestation of nationalism,
not of science, and such did their duty on the Hill appear at first to be.
ere
was “relatively little nuclear physics” at Los Alamos, Bethe says, mostly
cross-section calculations.1802 ey thought they were assembled to
engineer a “practical military weapon.
” at was first of all a national goal.
Science—a fragile, nascent political system of limited but increasing
franchise—would have to wait until the war was won.
Or so it seemed.
But a
few among the men and women gathered at Los Alamos—certainly Robert
Oppenheimer—sniffed a paradox.
ey proposed in fact to win the war with
an application of their science.
ey dreamed further that by that same
application they might forestall the next war, might even end war as a means
of settling differences between nations.
Which must in the long run have
decisive consequences, one way or the other, for nationalism.
* * *
By the time Robert Serber finished his orientation lectures at Los Alamos in
mid-April most of the scientific and technical staff was on hand, many
lodged temporarily in the surviving buildings of the Ranch School.
Now
began a second phase of the conference, to plan the laboratory’s work.
“If
there were any ground-breaking ceremonies at Los Alamos like champagne
or cutting ribbons,” John Manley comments, “I was unaware of them.
1803
Most of us who were there felt that the conference in April, 1943, was really
the ground-breaking ceremony.” 1804 Rabi, Fermi and Samuel Allison arrived
from Cambridge and Chicago to serve as senior consultants.
Groves
appointed a review committee—W.
K.
Lewis again, an engineer named E.
L.
Rose who was thoroughly experienced in ordnance design, Van Vleck,
Tolman and one other expert—to follow planning and advise.
Groves
despite his formidable competence as an organizer and administrator was
intellectually insecure around so many distinguished scientists, as who
would not be?
ey laid their plans, oen during hikes into the uninhabited wild
surroundings of the mesa.
ey had to rely heavily on theoretical
anticipations of the effects they wanted to study; that was their basic
constraint.
Any experimental device that demonstrated a fast-neutron chain
reaction to completion would use up at least one critical mass: there could
be no controlled, laboratory-scale bomb tests, no squash-court
demonstrations.
ey decided they had to analyze the explosion
theoretically and work out ways to calculate the stages of its development.
ey needed to understand how neutrons would diffuse through the core
and the tamper.
ey needed a theory of the explosion’s hydrodynamics—
the complex dynamic motions of its fluids, which the core and tamper
would almost instantly become as their metals heated from solid to liquid to
gas.
ey needed detailed experiments to observe bomb-related nuclear
phenomena and they needed integral experiments to duplicate as much as
possible the full-scale operation of the bomb.
ey had to develop an
initiator to start the chain reaction.
ey had to devise technology for
reducing uranium and plutonium to metal, for casting and shaping that
metal, possibly for alloying it to improve its properties.
Particularly with
plutonium, they had to discover and measure those properties in the first
place and do so quickly when more than microgram quantities began to
arrive.
As a sideline, because they agreed that work on the Super should
continue at second priority, they wanted to construct and operate a plant for
liquefying deuterium at −429°F—the cryogenics plant to be built near the
south rim of the mesa.
Ordnance work was crucial.
From the April discussions came immediate
breakthroughs.
An Oppenheimer recruit from the National Bureau of
Standards who had been a protégé at Caltech, a tall, thin, thirty-six-year-old
experimental physicist named Seth Neddermeyer, imagined an entirely
different strategy of assembly.1805 Neddermeyer could not quite remember
aer the war the complex integrations by which he came to it.
An ordnance
expert had been lecturing.
e expert had quibbled at the physicists’ use of
the word “explosion” to describe firing the bomb parts together.
e proper
word, the expert said, was “implosion.” During Serber’s lectures
Neddermeyer had already been thinking about what must happen when a
heavy cylinder of metal is fired into a blind hole in an even heavier metal
sphere.
Spheres and shock waves made him think about spherically
symmetrical shock waves, whatever those might be.
“I remember thinking
of trying to push in a shell of material against a plastic flow,” Neddermeyer
told an interviewer later, “and I calculated the minimum pressures that
would have to be applied.
en I happened to recall a crazy thing somebody
had published about firing bullets against each other.
It may have had a
photograph of two bullets liquefied on impact.
at is what I was thinking
when the ballistics man mentioned implosion.” 1806
Two bullets fired against each other recall the double-gun model of the
Los Alamos Primer.
ere were other clues to Neddermeyer’s new strategy
placed evocatively in the Primer as well.
at document notes that when the
surface of the bomb core blows off, it “expands into the tamper material,
starting a shock wave which compresses the tamper material
sixteenfold.” 1807 e Primer emphasizes more than once that the expansion of the core would be the greatest obstacle to an efficient explosion.
It may
have occurred to Neddermeyer that if a tamper merely by its inertia—by its
tendency to stay where it is when the swelling core begins to push out
against it—could resist the core’s expansion and thereby increase the
efficiency of the explosion, a tamper that somehow pushed back against the
core might do even better.
e compressing of the boron bubbles in the
autocatalytic bomb may also have been suggestive.
Finally, the Primer
offered the interesting model of four apple-quarter wedges of core/tamper
fired together by an encompassing explosive ring.
“At this point,” says
Neddermeyer, “I raised my hand.” 1808
He proposed packing a spherical layer of high explosives around a
spherical assembly of tamper and a hollow but thick-walled spherical core.
Detonated at many points simultaneously, the HE would blow inward.
e
shock wave from that explosion would squeeze the tamper from all sides,
which in turn would squeeze the core.
Squeezing the core would change its
geometry from hollow shell to solid ball.
What had been subcritical because
of its geometry would be squeezed critical far faster and more efficiently
than any mere gun could fire.
“e gun will compress in one dimension,”
Manley remembers Neddermeyer telling them.
“Two dimensions would be
better.
ree dimensions would be better still.” 1809
A three-dimensional squeeze inward was implosion.
Neddermeyer had
just defined a possible new way to fire an atomic bomb.
e idea had been
suggested previously, but no one had carried it beyond conversation.
“At a
meeting on ordnance problems late in April,” records the Los Alamos
technical history, “Neddermeyer presented the first serious theoretical
analysis of the implosion.
His arguments showed that the compression of
a...
sphere by detonation of a surrounding high-explosive layer was
feasible, and that it would be superior to the gun method both in its high
velocity and shorter path of assembly.” 1810
e response at the time was not encouraging.
“Neddermeyer faced stiff
opposition from Oppenheimer and, I think, Fermi and Bethe,” Manley
says.
1811 How do you make a shock wave spherically symmetrical?
How do
you keep tamper and core from squirting out in every direction as water
does when squeezed between cupped hands?
“Nobody...
really took
[implosion] very seriously,” Manley adds.
1812 But Oppenheimer had been
wrong before—even about the possibility of fission when Luis Alvarez
dropped by to report it in 1939, wrong for the fieen minutes it took him to
think past the stubbornness with which he rejected any possibility he had
not himself foreseen.
Apparently he was learning to steer by that grudging
incredulity as Bohr steered by the madness of a truly original idea.
“is will
have to be looked into,” he told Neddermeyer in private conference aer the
dismissive public debate.1813 He took his revenge for the trouble
Neddermeyer was causing him by appointing that thoroughgoing loner to
the newly invented post of group leader in the Ordnance Division for
implosion experimentation.
e other fresh insight remembered from the April conference corrected
an error that everyone wondered aerward how anyone could have
overlooked.
e error is perhaps a measure of how unfamiliar the physicists
were with ordnance.
E.
L.
Rose, the research engineer on Groves’ review
committee, woke up one day to realize that the Army cannon the physicists
were basing their estimates on weighed five tons only because it had to be
sturdy enough for repeated firing.
A gun that wore an atomic bomb welded
to its muzzle could be flimsier: it would be fired only once, aer which it
would vaporize and dri away.
at specification cut its weight drastically
and promised a practical, flyable bomb.
Fermi, superb experimentalist that he was, contributed valuably to the
program of experimental studies, defining with clarity problems that needed
to be examined.
For him the war work was duty, however, and the eager
conviction he found on the Hill puzzled him.
“Aer he had sat in on one of
his first conferences here,” Oppenheimer recalls, “he turned to me and said,
‘I believe your people actually want to make a bomb.’ I remember his voice
sounded surprised.” 1814
e leaders attended a party one night that April at Oppenheimer’s house,
the log-and-stucco former residence of the Ranch School headmaster.
Edward Condon, whose father had been a builder of railroads in the West,
who had worked as a newspaper reporter in tough Oakland, found occasion
at Oppenheimer’s party to satirize Los Alamos’ Panglossian mood.
1815 He
was an exceptional theoretician; he and Oppenheimer had boarded together
at Göttingen; Condon thought they were fast friends.
He would soon clash
bitterly with Groves over compartmentalization and find that his friend the
director had higher priorities than backing him up.
Now, sitting in a corner
at the director’s house, Condon pulled from a bookshelf a copy of
Shakespeare’s e Tempest and skimmed it for speeches meant for Prospero’s
enchanted island that might play contrapuntally against Oppenheimer’s high
and dry and secret mesa where no one had a street address, where mail was
censored, where drivers’ licenses went nameless, where children would be
born and families live and a few people die behind a post-office box in
devotion to the cause of harnessing an obscure force of nature to build a
bomb that might end a brutal war.
ere are many speeches in e Tempest
that would have fit the occasion but one certainly that Condon would not
have missed reading aloud to the assembled, Miranda’s speech that Aldous
Huxley borrowed for an ironic title:
O, wonder!
How many goodly creatures are there here!
How beauteous mankind is!
O brave new world
at has such people in’t!
e British had chosen not to bomb Vemork because Lief Tronstad, the
physical chemist attached to Norwegian intelligence in London, had warned
that hitting the hydrochemical facility’s liquid-ammonia storage tanks would
almost certainly kill large numbers of Norwegian workers.
But the British
had in any case long since abandoned precision bombing.
Winston Churchill had declared himself strongly in favor of strategic air
attack early in the war, speaking even of extermination.
In July 1940, in the
desperate time aer the debacle of Dunkirk and at the beginning of the
Battle of Britain, Churchill had written his Minister of Aircra Production
to that effect: “But when I look round to see how we can win the war I see
that there is only one sure path...
and that is absolutely devastating,
exterminating attack by very heavy bombers from this country upon the
Nazi homeland.
We must be able to overwhelm them by this means, without
which I do not see a way through.
”1816, 1817
e slide from precision bombing attacks on industry to general attacks
on cities followed less from political decisions than from inadequate
technology.
Bomber Command had attempted long-distance daylight
precision bombing early in the war but had been unable to defend its aircra
against German fighters and flak so far from home.
It therefore switched to
night bombing, which reduced losses but severely impaired accuracy.
If it
was logical to bomb factories and other strategic targets to reduce the
enemy’s ability to wage war, it began to seem equally logical to bomb the
blocks of workers’ housing that surrounded those targets; the workers, aer
all, made the factories run.
Sir Arthur Harris, who became chief of Bomber
Command in early 1942, notes in his war memoirs of this transitional
period in the summer of 1941 that “the targets chosen were in congested
industrial areas and were carefully picked so that bombs which overshot or
undershot the actual railway centers under attack [in this instance] should
fall on these areas, thereby affecting morale.
is programme amounted to a
halfway stage between area and precision bombing.” 1818 “Morale” is here and
elsewhere in the literature of air power a euphemism for the bombing of
civilians.
Another sign of halfway status at this stage was permission to
dump bombs before exiting Germany if crews had missed their targets.
Churchill says he authorized a study of bombing accuracy at Frederick
Lindemann’s suggestion which discovered in the summer of 1941 “that
although Bomber Command believed they had found the target, two-thirds
of crews actually failed to strike within five miles of it....
Unless we could
improve on this there did not seem much use in continued night
bombing.
”1819 In November the government ordered its bomber arm to
reduce operations over Germany.
To reduce strategic bombing operations was to admit failure in both
theory and practice, and it was to do so at a time when the USSR was fully
engaged with the German armies on the Eastern Front and Joseph Stalin
was demanding the Allies open a second front in the West.
Neither Britain
nor the United States was nearly prepared yet to invade Europe on the
ground, but both nations might offer such aid as air attack could bring.
Aiding the Soviet Union was a political justification for continuing some
kind of strategic bombing campaign, though it hardly placated Stalin.
Headlines proclaiming almost daily bombing raids also helped keep the
home front happy when the ground war stalled.1820
Yet Allied politics and domestic propaganda could not have been the
primary reasons for the dri from precision to area bombing, because U.S.
air forces beginning to arrive in Britain in 1942 planned and carried out
precision daylight bombing, though not oen effectively, until much later in
the war.
Rather, Bomber Command switched programs in order to justify its
continued existence as a service with a mission separate from Army and
Navy tactical support, cutting theory to fit the facts.
It found an ally in the
newly ennobled Lindemann, Lord Cherwell, who calculated in March 1942
that bombing might destroy the housing of a third of the German
population within a year if sufficiently pursued against industrial urban
areas.
Patrick Blackett and Henry Tizard thought Cherwell’s estimate far too
optimistic and dissented vigorously, but Cherwell had the Prime Minister’s
ear.Sir Arthur Harris—“Butch,” his staff came to call him, short for “the
Butcher”—took over Bomber Command in February and promulgated a
new approach to the air war: “It has been decided that the primary objective
of your operations should now be focussed on the morale of the enemy civil
population and in particular, of the industrial workers.” 1821 Harris had
witnessed the London Blitz; it convinced him, he writes, that “a bomber
offensive of adequate weight and the right kind of bombs would, if
continued for long enough, be something that no country in the world could
endure.
”1822 His argument was valid, of course, though what “the right kind
of bombs” might be would require the work of the Manhattan Project to
reveal.
Hitler’s terror bombing taught Britain not terror but forceful
imitation.
Harris certainly despised the Germans for starting and
perpetuating two world wars.
But he seems to have thought less about
killing civilians than about solving the problem of making Bomber
Command a measurably effective force.
If night bombing and area bombing
were the only tactics that paid a reasonable return in destruction at a
reasonable price in lost aircra and aircrew lives, then he would dedicate
Bomber Command to perfecting those tactics and measure success not in
factories rendered inoperative but in acres of cities flattened.
Which is to say,
area bombing was invented to give bombers targets they could hit.
An incendiary attack on the old Baltic port of Lübeck in March burned
much of the town and produced four-figure casualties for the first time in
the bombing campaign.
On May 20, to demonstrate Bomber Command’s
effectiveness at a time of public debate, Harris mustered every aircra he
could find—hundreds of two-engine bombers of light payload and even
training planes—to launch a thousand-bomber raid on Cologne.
For that
successful assault he organized what came to be called a bomber “stream,”
the aircra flying in massed continuous formations to overwhelm defenses
rather than in small and vulnerable packets as before, and destroyed some
eight square miles of the ancient city on the Rhine with 1,400 tons of bombs,
two-thirds of them incendiary.
Finally, in August, encouraged by Cherwell,
Bomber Command deployed a Pathfinder force: skilled advance crews that
marked targets with colored flares so that less experienced pilots following
in the lethal stream could more easily find their aiming points.
No fleet of bombers could yet accurately deliver enough high explosives to
raze a city.
e Lübeck bombing had been planned to test the theory that
area bombing worked best by starting fires.
If the bombloads were
incendiary, then the massed aircra might combine their destructiveness,
wind and weather cooperating, rather than disperse it on isolated targets.
e theory worked at Lübeck and again at Cologne and because it worked it
won adoption.
At the end of 1942 the British Chiefs of Staff called for “the
progressive destruction and dislocation of the enemy’s war industrial and
economic system, and the undermining of his morale to a point where his
capacity for armed resistance is fatally weakened.” Churchill and Roosevelt
affirmed the British plan for an aerial war of attrition in a directive issued at
the conclusion of the Casablanca Conference in late January 1943.
On May 27, 1943, as work began at Los Alamos following the April
conferences, Bomber Command ordered Hamburg attacked.
Its Most Secret
Operation Order No.
173 stated its new policy of mass destruction explicitly:
INFORMATION1823
e importance of HAMBURG, the second largest city in Germany with a population of one and a
half millions, is well known....
e total destruction of this city would achieve immeasurable
results in reducing the industrial capacity of the enemy’s war machine.
is, together with the
effect on German morale, which would be felt throughout the country, would play a very
important part in shortening and in winning the war.
2.
e “Battle of Hamburg” cannot be won in a single night.
It is estimated that at least 10,000
tons of bombs will have to be dropped to complete the process of elimination....
is city should
be subjected to sustained attack....
3....
It is hoped that the night attacks will be preceded and/or followed by heavy daylight attacks by the United States VIIIth Bomber Command.
INTENTION
4.
To destroy HAMBURG.
e operation was code-named Gomorrah.
Notice the significant claim that
it would help shorten and win the war.
Operation Gomorrah began on the night of July 24, 1943, a hot summer
Saturday in Hamburg under clear skies.1824 Pathfinder bombers used radar
to aid marking, and the initial Hamburg aiming point was chosen not for its
strategic significance but for its distinctive radar reflection: a triangle of land
at the junction of the Alster and North Elbe rivers, near the oldest part of the
city and far from any war industry.
Bomber Command had learned to adjust
targeting for creep-back, the tendency of bombardiers to release their bombs
as quickly as possible upon approaching the flak-infested aiming point that
led to a gradual backup of impacts.
From the ground the bombs seemed to
unroll in the direction of the bomber stream’s approach; survivors named
the phenomenon “carpet bombing.” Targeters incorporated creep-back into
their calculations by setting the aiming point several miles forward of the
intended target area.
e creep-back districts behind the Hamburg aiming
point to a distance of four miles were entirely residential.
To give the bombers further advantage Churchill had authorized the first
use of the secret radar-jamming device known as Window: bales of 10.5 -
inch strips of aluminum foil to be pushed out of the bombers en route to the
target to disperse on the wind and cloud German defensive radar.
Window
worked so well that of the 791 planes of the initial raid only twelve were lost.
Hamburg sustained heavy damage that first night but not damage even on
the scale of Cologne; 1,300 tons of high explosives and almost 1,000 tons of
incendiaries killed about 1,500 people and le many thousands homeless.
More important for what would follow, the first raid seriously disrupted
communications and overwhelmed firefighting forces.
Daylight precision bombing by American B-17’s followed on July 25 and
26, attacks meant for a submarine yard and an aircra engine factory.
Smoke
from the British bombing and from German defensive generators obscured
the targets and they were only lightly damaged.
Harris ordered a maximum bombing effort against Hamburg again for the
night of July 27.
Targeters fixed the same aiming point but aligned the
bomber stream to approach from the northeast rather than the north to set
its creep-back over districts dense with workers’ apartment buildings.
Since
the mix of 787 bombers for this second raid would include more Halifaxes
and Stirlings, and they could carry less weight of weapons and fuel than the
longer-distance Lancasters, the mix of bombs was also changed, high
explosives reduced and incendiaries increased to more than 1,200 tons.
More experienced pilots also came aboard, higher-ranking officers signing
on to observe the effects of Window.
ese accidents of arrangement
contributed their share to the night’s catastrophe.
At 6 P.M.
in Hamburg on July 27 the temperature was 86 degrees and the
humidity 30 percent.
Fires still burned in stores of coal and coke in the
western sector of the city.
Since the fires would render a blackout ineffective
most of Hamburg’s firefighting equipment had been moved to the area to
douse them.
“It was completely quiet,” recalls a German woman who lived in
a district targeted for creep-back, miles to the northeast.
“...
It was an
enchantingly beautiful summer night.
”1825
Pathfinders started dropping yellow markers and bombs at fiy-five
minutes past midnight on July 28.
Five minutes later the main bomber
stream arrived.
Marking was good and creep-back was slow.
Later arrivals
began to notice a difference between this raid and others they had flown:
“Most of the raids we did looked like gigantic firework displays over the
target area,” a flight sergeant remarks, “but this was ‘the daddy of them
all.’ ”1826 A flight lieutenant distinguishes the difference:
e burning of Hamburg that night was remarkable in that I saw not many fires but one.
Set in the
darkness was a turbulent dome of bright red fire, lighted and ignited like the glowing heart of a
vast brazier.
I saw no flames, no outlines of buildings, only brighter fires which flared like yellow
torches against a background of bright red ash.
Above the city was a misty red haze.
I looked
down, fascinated but aghast, satisfied yet horrified.
I had never seen a fire like that before and was
never to see its like again.1827
e summer heat and low humidity, the mix of high-explosive and
incendiary bombs that made kindling and then ignited it and the absence of
firefighting equipment in the bombed districts conspired to assemble a new
horror.
An hour aer the bombing began the horror had a name, recorded
first in the main log of the Hamburg Fire Department: Feuersturm:
firestorm.
A Hamburg factory worker remembers its beginning, some
twenty minutes into the one-hour bombing raid:
en a storm started, a shrill howling in the street.
It grew into a hurricane so that we had to abandon all hope of fighting the [factory] fire.
It was as though we were doing no more than
throwing a drop of water on to a hot stone.
e whole yard, the canal, in fact as far as we could see,
was just a whole, great, massive sea of fire.
1828
Small fires had coalesced into larger fires and, greedy for oxygen, had sucked
air from around the coalescing inferno and fanned further fires there.
at
created the wind, a thermal column above the city like an invisible chimney
above a hearth; the wind heated the fury at the center of the firestorm to
more than 1,400 degrees, heat sufficient to melt the windows of a streetcar,
wind sufficient to uproot trees.
A fieen-year-old Hamburg girl recalls:
Mother wrapped me in wet sheets, kissed me, and said, “Run!” I hesitated at the door.
In front of
me I could see only fire—everything red, like the door to a furnace.
An intense heat struck me.
A
burning beam fell in front of my feet.
I shied back but, then, when I was ready to jump over it, it
was whirled away by a ghostly hand.
I ran out to the street.
e sheets around me acted as sails and
I had the feeling that I was being carried away by the storm.
I reached...
a five-storey building in
front of which we had arranged to meet again....
Someone came out, grabbed me by the arm, and
pulled me into the doorway.1829
e fire filled the air with burning embers and melted the streets, a
nineteen-year-old milliner reports:
We came to the door which was burning just like a ring in a circus through which a lion has to
jump....
e rain of large sparks, blowing down the street, were each as large as a five-mark piece.
I struggled to run against the wind in the middle of the street but could only reach a house on the
corner....
1830
We got to the Löschplatz [park] all right but I couldn’t go on across the Eiffestrasse because the
asphalt had melted.
ere were people on the roadway, some already dead, some still lying alive
but stuck in the asphalt.
ey must have rushed on to the roadway without thinking.
eir feet had
got stuck and then they had put out their hands to try to get out again.
ey were on their hands
and knees screaming.
e firestorm completely burned out some eight square miles of the city,
an area about half as large as Manhattan.
e bodies of the dead cooked in
pools of their own melted fat in sealed shelters like kilns or shriveled to
small blackened bundles that littered the streets.
Or worse, as the woman
who was once the fieen-year-old girl horribly recreates:
Four-storey-high blocks of flats [the next day] were like glowing mounds of stone right down to
the basement.
Everything seemed to have melted and pressed the bodies away in front of it.
Women and children were so charred as to be unrecognizable; those that had died through lack of
oxygen were half-charred and recognizable.
eir brains had tumbled from their burst temples and
their insides from the so parts under the ribs.
How terribly these people must have died.
e
smallest children lay like fried eels on the pavement.
1831
Bomber Command killed at least 45,000 Germans that night, the majority of
them old people, women and children.
e bombing of Hamburg was hardly unique.
It was one atrocity in a war
of increasing atrocities.
Between 1941 and 1943 the German Army on the
Eastern Front captured and enclosed in prisoner-of-war camps without food
or shelter some two million Soviet soldiers; at least one million of them died
of exposure and starvation.1832 During the same period the Final Solution to
the Jewish Question—the vast Nazi program to exterminate the European
Jews—began in deadly earnest aer the Wannsee Conference of
coordinating agencies met in suburban Berlin on January 20, 1942.
Whatever moral issues such atrocities raise, they resulted from the
progressive escalation of the war by all its belligerents in pursuit of victory.
(Even the Final Solution: because the Nazis believed the Jews constituted a
separate nation lodged subversively in their midst—nationality being
defined in the Nazi canon primarily in terms of race—and as such the nation
with which the ird Reich was preeminently at war.
It was Hitler’s
particular perversity to define victory over the Jews as extermination; the
Allies in their defensive war against Germany and Japan wanted only total
surrender, in return for which the mass killing of combatants and civilians
would stop.)
One way the belligerents could escalate was to improve their death
technologies.
Better bombers and better bomber defenses such as Window
were hardware improvements; so were the showers at the death camps
efficiently pumped with the deadly fumigant Zyklon B.
e bomber-stream
system and allowance for creep-back were soware improvements; so were
the schedules Adolf Eichmann devised that kept the trains running
efficiently to the camps.
e other way the belligerents could escalate was to enlarge the range of
permissible victims their death technologies might destroy.
Civilians had the
misfortune to be the only victims le available.
Better hardware and
soware began to make them also accessible in increasing numbers.
No
great philosophical effort was required to discover acceptable rationales.
War begot psychic numbing in combatants and civilians alike; psychic
numbing prepared the way for increasing escalation.
Extend war by attrition to include civilians behind the lines and war
becomes total.
With improving technology so could death-making be.
e
bombing of Hamburg marked a significant step in the evolution of death
technology itself, massed bombers deliberately churning conflagration.
It
was still too much a matter of luck, an elusive combination of weather and
organization and hardware.
It was still also expensive in crews and matériel.
It was not yet perfect, as no technology can ever be, and therefore seemed to
want perfecting.
e British and the Americans would be enraged to learn of Japanese
brutality and Nazi torture, of the Bataan Death March and the fathomless
horror of the death camps.
By a reflex so mindlessly unimaginative it may be
merely mammalian, the bombing of distant cities, out of sight and sound
and smell, was generally approved, although neither the United States nor
Great Britain admitted publicly that it deliberately bombed civilians.
1833 In
Churchill’s phrase, the enemy was to be “de-housed.” e Jap and the Nazi in
any case had started the war.
“We must face the fact that modern warfare as
conducted in the Nazi manner is a dirty business,” Franklin Roosevelt told
his countrymen.
“We don’t like it—we didn’t want to get in it—but we are in
it and we’re going to fight it with everything we’ve got.” 1834
* * *
e Los Alamos review committee headed by W.K.
Lewis of MIT reported
its findings on May 10, 1943.
It approved the laboratory’s nuclear physics
research program.
It recommended that theoretical investigation of the
thermonuclear bomb continue at second priority, subordinate to fission
bomb work.
It proposed a major change in the chemistry program: final
purification of plutonium on the Hill, because Los Alamos would be
ultimately responsible for the performance of the plutonium bomb and
because the scarce new element would be used and reused for experiments
during the months before a sufficient quantity accumulated to load a bomb
and would have to be frequently repurified.
e Lewis committee also
concurred in a recommendation Robert Oppenheimer had made in March
that ordnance development and engineering should begin immediately at
Los Alamos rather than wait until nuclear physics studies were complete.
General Groves accepted the committee’s findings; they dictated an
immediate doubling of Hill personnel.
1835 ereaer until the end of the
war the Los Alamos working population would double every nine months.
e dust of construction never settled; housing would always be short, water
scarce, electricity intermittent.
Groves spent not a penny more than
necessary on comforts for civilians.
e bottom pole piece of the Harvard cyclotron had been laid on April 14;
by the first week in June Robert Wilson’s cyclotron group saw signs of a
beam.
e Wisconsin long-tank Van de Graaff came on line at 4 million
volts on May 15 and the 2 MV short-tank Van de Graaff on June 10.
In July
the first physics experiment completed at Los Alamos counted the number
of secondary neutrons Pu239 emitted when it fissioned.
“In this
experiment,” says the Los Alamos technical history, “the neutron number
was measured from an almost invisible speck of plutonium and found to be
somewhat greater even than for U235.” 1836 e experiment thus established
what had not yet been confirmed despite the expensive rush of building: that
plutonium emitted sufficient secondary neutrons to chain-react.
e speck of plutonium was Glenn Seaborg’s 200-milligram sample of Met
Lab oxide, which he had sent to Los Alamos at the beginning of the month.
Seaborg had worked himself sick at the Met Lab that spring—an upper
respiratory infection compounded with exhaustion and a persistent fever—
and came to New Mexico with his wife during July to vacation.
(“I guess I
deliberately chose to be near the plutonium,” he muses.
“I wonder why?”)
Too much peace and quiet at a guest ranch threatened to exhaust him
further and on July 21 he and his wife moved to the adobe-style La Fonda
Hotel in Santa Fe.
1837 Compartmentalization put Los Alamos off limits.
e
Seaborgs were ready to return to Chicago on Friday, July 30, and Seaborg
proposed to carry the Pu sample, most of the world’s supply, back with him
on the train.
Robert Wilson and another physicist made the transfer before
dawn in the restaurant where the Seaborgs were having breakfast in Santa
Fe, Wilson arriving in a pickup armed Western-style with his personal
Winchester.32 deer-hunting rifle to guard a highly valuable but barely
visible treasure.
“en I just put it in my pocket and then into my suitcase,”
Seaborg remembers.
1838 He proceeded to Chicago unarmed.
To direct the expanded Ordnance Division Groves asked the Military
Policy Committee in Washington to recommend a good man, preferably a
military officer.
Vannevar Bush knew a naval officer—would Groves mind?
“Of course not,” the general humphed.
1839 Bush proposed Captain William
S.
“Deke” Parsons, a 1922 Annapolis graduate then responsible under Bush
for field-testing the proximity fuse.
1
Parsons had also worked on early radar development and served as
gunnery officer on a destroyer and experimental officer at the Naval Proving
Ground in Dahlgren, Virginia.
He was forty-three, cool, vigorous, trim,
nearly bald, spit-and-polish but innovative; “all his life,” one of the men who
worked for him at Los Alamos testifies in praise, “he fought the silly
regulations and the conservatism of the Navy.
”1840 Groves liked him; “within
a few minutes [of meeting him],” the general says, “I was sure he was the
man for the job.
”1841 Oppenheimer interviewed the man for the job in
Washington and agreed.
Parsons was married to Martha Cluverius, a Vassar
graduate and the daughter of an admiral; with two blond daughters and a
cocker spaniel the couple arrived at Los Alamos in an open red convertible
in June.
Parsons’ first order of business was the plutonium gun.
Because it needed
a muzzle velocity of at least 3,000 feet per second it would have to be 17 feet
long.
It should weigh no more than a ton, a fih of the usual weight of a gun
that size, which meant it would have to be machined from strong high-alloy
steel.
It would not require rifling but needed three independently operated
primers to make sure it fired.
Parsons arranged for the Navy’s gun-design
section to engineer it.
Norman F.
Ramsey, a tall young Columbia physicist, the son of a general,
served under Parsons as group leader for delivery: for devising a way to
deliver the bombs to their targets and drop them.
In June he contacted the
U.S.
Air Force to identify a combat aircra that could carry a 17-foot bomb.
“As a result of this survey,” Ramsey writes, “it was apparent that the B-29 was
the only United States aircra in which such a bomb could be conveniently
carried internally, and even this plane would require considerable
modification so that the bomb could extend into both front and rear bomb
bays....
1843, 1844 Except for the British Lancaster, all other aircra would require such a bomb to be carried externally.” e Air Force was not about
to allow a historic new weapon of war to be introduced to the world in a
British aircra, but the B-29 Superfortress was a new design still plagued
with serious problems.
e first service-test model had not yet flown when
Ramsey began his aircra survey in June; a flight-test model had crashed
into a Seattle packing house in February and killed the plane’s entire test
crew and nineteen packing-house workers.
Ramsey did not have to wait for access to a B-29 to begin collecting data
on the long bomb’s ballistics, however.
He mocked up a scale model and
arranged to see it dropped:
On August 13, 1943, the first drop tests of a prototype atomic bomb were made at the Dahlgren
Naval Proving Ground [by a Navy TBF aircra] to determine stability in flight.
ese tests were on
a 14/23 scale model of a bomb shape which was then thought probably suitable for a gun assembly.
Essentially, the model consisted of a long length of 14-inch pipe welded into the middle of a split
standard 500-pound bomb.
It was officially known at Dahlgren as the “Sewer Pipe Bomb.”...
e
first test...
was an ominous and spectacular failure.
e bomb fell in a flat spin such as had rarely
been seen before.
However, an increase in fin area and a forward movement of the center of gravity
provided stability in subsequent tests.1845
In the meantime Seth Neddermeyer, whose implosion experimentation
group Parsons inherited, had visited a U.S.
Bureau of Mines laboratory at
Bruceton, Pennsylvania, to experiment with high explosives.
Edwin
McMillan, who was interested in implosion, went with the Caltech physicist:
At that point it was just Seth and myself with a few helpers.
e first cylindrical implosions were
done at Bruceton.
You take a piece of iron pipe, wrap the explosives around it, and ignite it at
several points so that you get a converging wave and squash the cylinder in.
at was the birth of
the experimental work on implosion, long before experimental work on the gun method.
1846
Back at Los Alamos Neddermeyer set up a small research station on South
Mesa, the next mesa south of the Hill across Los Alamos canyon.
He fired
his first tests in an arroyo on Independence Day, 1943, using iron pipe set in
cans packed with TNT.
Experimenting with cylinders rather than spheres
simplified calculation.
Because he wanted to recover the results he packed
only limited amounts of explosive.
“ose tests of course could not be very
sophisticated,” says McMillan.
“...
ey did show that you could take metal
pipes and close them right in so that they became like solid bars, indicating
that this was a practical method.” 1847 ey also showed that the squeeze was
far from uniform: the pipes emerged from the arroyo dust twisted and
deformed.
When Parsons, a thoroughly pragmatic engineer, had time to look over
Neddermeyer’s work he was openly contemptuous.
He doubted if implosion
could ever be made reliable enough for field use.
Neddermeyer presented his
initial results at one of the weekly colloquia Oppenheimer had instituted at
Hans Bethe’s suggestion to keep everyone with a white badge—everyone
cleared for secrets—informed of Tech Area progress.
Richard P.
Feynman, a
brilliant, outspoken New York-born graduate-student theoretician from
Princeton, summarized the opinion of the assembly in a phrase: “It
stinks.” 1848 In the name of lightheartedness Parsons was crueler.
“With
everyone grinding away in such dead earnest here,” he told the group, “we
need a touch of relief.
I question Dr.
Neddermeyer’s seriousness.
To my
mind he is gradually working up to what I shall refer to as the Beer-Can
Experiment.
1849 As soon as he gets his explosives properly organized, we will
see this done.
e point to watch for is whether he can blow in a beer can
without splattering the beer.” Implosion was even harder to do than that.
John von Neumann, the Hungarian mathematician who had come to the
United States in 1930 and joined the Institute for Advanced Study, had been
examining for the NDRC the complex hydrodynamics of shock waves
formed by shaped charges, technology which was being applied to the
American tank-killing infantry weapon known as the bazooka.
Like Rabi,
von Neumann had agreed to serve as an occasional Oppenheimer
consultant.
He visited Los Alamos at the end of the summer and looked into
implosion theory, another warren of hydrodynamic complexity.
Neddermeyer had devised “a simple theory that worked up to a certain level
of violence in the shockwave.” Von Neumann, he says, “is generally credited
with originating the science of large compressions.
But I knew it before and
had done it in a naive way.
Von Neumann’s was more sophisticated.
”1850
“Johnny was quite interested in high explosives,” Edward Teller
remembers.
Teller and von Neumann renewed their youthful acquaintance
during the mathematician’s visit to the Hill.
“In my discussions with him
some crude calculations were made,” Teller continues.
“e calculation is
indeed simple as long as you assume that the material to be accelerated is
incompressible, which is the usual assumption about solid matter....
In
materials driven by high explosives, pressures of more than 100,000
atmospheres occur.” Von Neumann knew that, Teller says, as he did not.
On
the other hand:
If a shell moves in one-third of the way toward the center you obtain under the assumption of an
incompressible material a pressure in excess of eight million atmospheres.
is is more than the
pressure in the center of the earth and it was known to me (but not to Johnny), that at these pressures, iron is not incompressible.
In fact I had rough figures for the relevant compressibilities.
e result of all this was that in the implosion significant compressions will occur, a point which
had not been previously discussed.1851
It had been clear from the beginning that implosion, by squeezing a
hollow shell of plutonium to a solid ball, could effectively “assemble” it as a
critical mass much faster than the fastest gun could fire.
What von
Neumann and Teller now realized, and communicated to Oppenheimer in
October 1943, was that implosion at more violent compressions than
Neddermeyer had yet attempted should squeeze plutonium to such
unearthly densities that a solid subcritical mass could serve as a bomb core,
avoiding the complex problem of compressing hollow shells.
Nor would
predetonation threaten from light-element impurities.
Develop implosion,
in other words, and they could deliver a more reliable bomb more quickly.
It was possible at that point to estimate roughly the size and shape of a
bomb that worked by fast implosion.
e big gun bomb would be just under
2 feet in diameter and 17 feet long.
An implosion bomb—a thick shell of
high explosives surrounding a thick shell of tamper surrounding a
plutonium core surrounding an initiator—would be just under 5 feet in
diameter and a little over 9 feet long: a man-sized egg with tail fins.
Norman Ramsey started planning full-scale drop tests that autumn as the
aspens brightened to yellow at Los Alamos.
He offered to practice with a
Lancaster.
e Air Force insisted he practice with a B-29 even though the
new polished-aluminum intercontinental bombers were just beginning
production and still scarce.
“In order that the aircra modifications could
begin,” Ramsey writes in his third-person report on this work, “Parsons and
Ramsey selected two external shapes and weights as representative of the
current plans at Site Y....
1852, 1853 For security reasons, these were called by the Air Force representatives the ‘in Man’ and the ‘Fat Man,’ respectively;
the Air Force officers tried to make their phone conversations sound as
though they were modifying a plane to carry Roosevelt (the in Man) and
Churchill (the Fat Man)....
Modification of the first B-29 officially began
November 29, 1943.”
* * *
A captain of the Danish Army who was also a member of the Danish
underground visited Niels Bohr at the House of Honor in Copenhagen early
in 1943.
Aer tea the two men retired to Bohr’s greenhouse where hidden
microphones might not overhear their conversation.
e British had
instructed the underground that they would soon be sending Bohr a set of
keys.
Blind holes had been drilled in the bows of two of the keys, identical
microdots implanted and the holes sealed.
A captioned diagram located the
holes.
“Professor Bohr should gently file the keys at the point indicated until
the hole appears,” the document explained.
“e message can then be
syringed or floated out onto a micro-slide.” 1854 e captain offered to extract
the microdot and have it enlarged.
Bohr was no secret agent; he accepted the
offer gratefully.
When the message arrived it proved to be a letter from James Chadwick.
“e letter contained an invitation to my father to go to England, where he
would find a very warm welcome,” Aage Bohr remembers.
“...
Chadwick
told my father that he would be able to work freely on scientific matters.
But
it was also mentioned that there were special problems in which his co-
operation would be of considerable help.
”1855 Bohr understood that
Chadwick might be hinting about work on nuclear fission.
e Danish
physicist was still skeptical of its application.
He would not stay in Denmark,
he wrote Chadwick in return, “if I felt that I could be of real help...
but I do
not think that this is probable.
Above all I have to the best of my judgment
convinced myself that, in spite of all future prospects, any immediate use of
the latest marvelous discoveries of atomic physics is impracticable.” If an
atomic bomb were a serious possibility Bohr would leave.
Otherwise he had
compelling reasons to stay “to help resist the threat against the freedom of
our institutions and to assist in the protection of the exiled scientists who
have sought refuge here.
”1856
e threat against Danish institutions that Bohr was helping to resist was
peculiar to the German occupation of Denmark.
Germany relied heavily on
Danish agriculture, which supplied meat and butter rations to 3.6 million
Germans in 1942 alone.1857 It was a labor-intensive agriculture of small
farms and it could only continue with the cooperation of the farmers and,
more broadly, of the entire Danish population.
Not to arouse resistance the
Nazis had allowed Denmark to keep its constitutional monarchy and
continue to govern itself.
e Danes in turn had extracted an extraordinary
price for agreeing to cooperate under foreign occupation: the security of
Danish Jews.
To the Danes the eight thousand Jews in Denmark, 95 percent
of them in Copenhagen, were Danish citizens first of all; their security was
therefore a test of German good faith.
“Danish statesmen and heads of
government,” reports a historian, “one aer the other, had made the security
of the Jews a conditio sine qua non for the maintenance of a constitutional
Danish government.
”1858
But resistance, especially strikes and sabotage, gradually increased as the
Danish people felt the occupation’s burden and as the tides of war began to
turn against the Axis powers.
e German surrender at Stalingrad on
February 2, 1943, may have appeared to many Danes to be a turning point.
Mussolini’s resignation and arrest the following summer on July 25 and the
impending surrender of Italy certainly did.
On August 28 the Nazi
plenipotentiary for Denmark, Dr.
Karl Rudolf Werner Best, presented the
Danish government with an ultimatum at Hitler’s orders demanding that it
declare a state of national emergency, forbid strikes and meetings and
introduce a curfew, a ban on arms, press censorship at German hands and
the death penalty for harboring arms and for sabotage.
With the King’s
permission the government refused.
On August 29 the Nazis reoccupied
Copenhagen, disarmed the Danish Army, blockaded the royal palace and
confined the King.
One reason for the takeover was Nazi determination to eliminate the
Danish Jews, whose exemption from the Final Solution infuriated Hitler.
e Nazis had arrested several Jewish notables on August 29 (they had
planned to arrest Bohr but had decided the deed would be less obvious
during a general roundup).
In early September Bohr learned from the
Swedish ambassador in Copenhagen that his emigré colleagues, including
his collaborator Stefan Rozental, were slated for arrest.
He contacted the
underground, which helped the emigrés escape across the Öresund to
Sweden.
Rozental endured nine stormy hours crowded with other refugees
in a rowboat borrowed from a city park before his exhausted party made
Swedish landfall.
Bohr’s turn came soon aer.
e Swedish ambassador took tea at the
House of Honor on September 28 and hinted that Bohr would be arrested
within a few days.
Even professors were leaving Denmark, Margrethe Bohr
remembers the diplomat emphasizing.
1859 e next morning word came
through her brother-in-law that an anti-Nazi German woman working at
Gestapo offices in Copenhagen had seen orders authorized in Berlin for the
arrest and deportation of Niels and Harald Bohr.
“We had to get away the same day,” Margrethe Bohr said aerward.
“And
the boys would have to follow later.
But many were helping.
Friends
arranged for a boat, and we were told we could take one small bag.
”1860, 1861
In the late aernoon of September 29 the Bohrs walked through
Copenhagen to a seaside suburban garden and hid in a gardener’s shed.
ey waited for night.
At a prearranged time they le the shed and crossed
to the beach.
A motorboat ran them out to a fishing boat.
reading
minefields and German patrols they crossed the Öresund by moonlight and
landed at Linhamm, near Malmö.
Bohr had learned at the last minute that the Nazis planned to round up all
the Danish Jews the next evening and deport them to Germany.
Leaving his
wife in southern Sweden to await the crossing of their sons he rushed to
Stockholm to appeal to the Swedish government for aid.
He discovered that
the Swedes had offered to intern the Danish Jews but the Germans had
denied that any roundup was planned.
In fact it proceeded on schedule while Bohr worked his way through the
Swedish bureaucracy, but fell far short of success.
e Danes, warned in
advance, had spontaneously hidden their Jewish fellow citizens away.
Only
some 284 elderly rest-home residents had been seized.1862 e more than
seven thousand Jews remaining in Denmark were temporarily safe.
But few
of them planned at first to leave the country; it was far from certain that
Sweden would accept them and there seemed nowhere else to go.
Meeting with the Swedish Undersecretary for Foreign Affairs on
September 30 Bohr had urged that Sweden make public its protest note to
the German Foreign Office.
1863 He saw that publicity would alert the
potential victims, signal Swedish sympathy and bring pressure to bear on the
Nazis to desist.
e Undersecretary told him Sweden planned no further
intervention beyond the confidential note.
Bohr appealed to the Foreign
Minister on October 2, failed to win publication of the note and determined
to dispense with intermediaries.
Rozental says the Danish laureate “went to
see Princess Ingeborg (the sister of the Danish king Christian X) and while
there expressed the desire to be received by the King of Sweden.” 1864 Bohr
also contacted the Danish ambassador and influential Swedish academic
colleagues.
1865 Rozental describes the crucial meeting with the King:
e audience...
took place that aernoon....
King Gustaf said that the Swedish Government had tried a similar approach to the Germans once before, when the occupying power had started
deporting Jews from Norway.1866 e...
approach, however, had been rejected....
Bohr objected that in the meantime the situation had changed decisively by reason of the Allied victories, and he
suggested that the offer by the Swedish government to assume responsibility for the Danish Jews
should be made public.
e King promised to talk to the Foreign Minister at once, but he
emphasized the great difficulties of putting the plan into operation.
e difficulties were overcome.
Swedish radio broadcast the Swedish
protest that evening, October 2, and reported the country ready to offer
asylum.
e broadcast signaled a route of escape; in the next two months
7,220 Jews crossed to safety in Sweden with the active help of the Swedish
coast guard.
One refugee’s report of what first alerted him in hiding to the
idea of escape is typical: “At the pastor’s house I heard on the Swedish radio
that the Bohr brothers had fled to Sweden by boat and that the Danish Jews
were being cordially received.” 1867 With personal intervention on behalf of
the principle of openness, which exposes crime as well as error to public
view, Niels Bohr played a decisive part in the rescue of the Danish Jews.
Stockholm was alive with German agents and there was fear that Bohr
would be assassinated.
“e stay in Stockholm lasted only a short time,”
remembers Aage Bohr.
“...
A telegram was received from Lord
Cherwell...
with an invitation to come to England.
My father immediately
accepted and requested that I should be permitted to accompany him.” Aage
was twenty-one at the time and a promising young physicist.
“It was not
possible for the rest of the family to follow; my mother and brothers stayed
in Sweden.” 1868
Bohr went first.
e British flew their diplomatic pouch back and forth
from Stockholm in an unarmed two-engine Mosquito bomber, a light, fast
aircra that could fly high enough to avoid the German anti-aircra
batteries on the west coast of Norway—flak usually topped out at 20,000
feet.
e Mosquito’s bomb bay was fitted for a single passenger.
On October
6 Bohr donned a flight suit and strapped on a parachute.
e pilot supplied
him with a flight helmet with built-in earphones for communication with
the cockpit and showed him the location of his oxygen hookup.
Bohr also
took delivery of a stick of flares.
In case of attack the pilot would dump the
bomb bay and Bohr would parachute into the cold North Sea; the flares
would aid his rescue if he survived.
“e Royal Air Force was not used to such great heads as Bohr’s,” says
Robert Oppenheimer wryly.1869 Aage Bohr describes the near-disaster:
e Mosquito flew at a great height and it was necessary to use oxygen masks; the pilot gave word
on the inter-com when the supply of oxygen should beturned on, but as the helmet with the
earphones did not fit my father’s head, he did not hear the order and soon fainted because of lack
of oxygen.
1870 e pilot realized that something was wrong when he received no answer to his inquiries, and as soon as they had passed over Norway he came down and flew low over the North
Sea.
When the plane landed in Scotland, my father was conscious again.
e vigorous fiy-eight-year-old was none the worse for wear.
“Once in
England and recovered,” Oppenheimer continues the story, “he learned from
Chadwick what had been going on.” 1871 Aage arrived a week later and father
and son toured Britain observing the developing activities there of the Tube
Alloys project, which included a section of a pilot-scale gaseous-diffusion
plant.
But the center of gravity had long since shied to the United States.
e British were preparing to recover a share of the initiative by sending a
mission to Los Alamos to help design the bombs; they wanted Bohr on their
team to increase its influence and prestige.
By then the Danish theoretician
had taken what Oppenheimer calls a “good first look.” At how nuclear
weapons would change the world, Oppenheimer means.
He emphasizes
Bohr’s developing understanding then with a potent simile: “It came to him
as a revelation, very much as when he learned of Rutherford’s discovery of
the nucleus [thirty] years before.” 1872
So Niels Bohr prepared in the early winter of 1943 to travel to America
once again with an important and original revelation in hand, this one in the
realm not of physics but of the political organization of the world.
He was willing to be impressed by a mighty progress of industry.
“e
work on atomic energy in the USA and in England proved to have advanced
much further than my father had expected,” Aage Bohr understates.1873
Robert Oppenheimer pitches his summary closer to the shock of surprise a
refugee released from the suspended animation that had been occupied
Denmark would have felt: “To Bohr the enterprises in the United States
seemed completely fantastic.” 1874
ey were.
15
Different Animals
e 59,000 acres of Appalachian semiwilderness along the Clinch River in
eastern Tennessee that Brigadier General Leslie R.
Groves acquired for the
Manhattan Engineer District as one of his first official acts, in September
1942, extended from the Cumberland foothills in a series of parallel,
southwestern-running ridge valleys.
Groves liked the geology, which offered
isolation for his several enterprises, but the new reservation was nearly as
primitive as Los Alamos would be.
e Clinch, a meandering tributary of
the Tennessee, defined the reservation’s southeastern and southwestern
boundaries.
Eastward twenty miles was Knoxville, a city of nearly 112,000,
farther east the wall of Great Smoky Mountains National Park.
Five unpaved
county roads traversed the ninety-two square miles of depleted valleys and
scrub-oak ridges, an area seventeen miles long and seven miles wide that
supported only about a thousand families in rural poverty.
In the ridge-
barricaded valleys of this impoverished hill country, far from prying eyes,
the United States Army intended to construct the futuristic factories that
would separate U235 from U238 in quantity sufficient to make an atomic
bomb.
To do so it had first to improve communications and build a town.
Into
the gummy red eastern-Tennessee clay in the winter of 1942 and the spring
of 1943 its contractors cut fiy-five miles of rail roadbed and three hundred
miles of paved roads and streets.
ey improved the important county roads
to four-lane highways.
Stone & Webster, the hard-pressed Boston
engineering corporation, laid out a town plan so unimaginative that the
MED rejected it and passed the assignment to the ambitious young
architectural firm of Skidmore, Owings and Merrill, which produced a
wellsited arrangement of housing using innovative new materials that saved
enough money to allow for such amenities in the best residences as
fireplaces and porches.
e new town, planned initially for thirteen
thousand workers, took its name from its location lining a long section of
the northwesternmost valley: Oak Ridge.
e entire reservation, fenced with
barbed wire and controlled through seven guarded gates, was named, aer a
nearby Tennessee community, the Clinton Engineer Works.
Its workers
would come to call it Dogpatch in homage to the hillbilly comic strip “Li’l
Abner.” e new gates closed off public access on April 1.
Groves planned to build electromagnetic isotope separation plants and a
gaseous-diffusion plant at Clinton; plutonium production, he realized
during his first months on the project, would proceed at such a scale and
generate so vast a quantity of potentially dangerous radioactivity that it
would require a separate reservation of its own.
Of the three processes,
Ernest Lawrence’s electromagnetic method was farthest along.
Electromagnetic isotope separation enlarged and elaborated Francis
Aston’s 1918 Cavendish invention, the mass spectrograph.
As a 1945 report
prepared by Lawrence’s staff explains, the method “depends on the fact that
an electrically charged atom traveling through a magnetic field moves in a
circle whose radius is determined by its mass”—which was also a basic
principle of Lawrence’s cyclotron.1875 e lighter the atom, the tighter the
circle it made.
Form ions of a vaporous uranium compound and start them
moving at one side of a vacuum tank permeated by a strong magnetic field
and the moving ions as they curved around would separate into two beams.
Lighter U235 atoms would follow a narrower arc than heavier U238 atoms;
across a four-foot semicircle the separation might be about three-tenths of
an inch.
Set a collecting pocket at the point where the U235 ion beam
separately arrived and you could catch the ions.
“When the ions strike the
bottom of the collecting pocket...
they give up their charge and are
deposited as flakes of metal.” 1876 Schematically, with slotted electrodes to
accelerate the ions, the arrangement would look like the illustration on page
488.
Late in 1941 Lawrence had installed such a 180-degree mass spectrometer
in place of the dees in the Berkeley 37-inch cyclotron.
By running it
continuously for a month his crews produced a partially separated 100-
microgram sample of U235.
1877 at was several hundred million times less
than the 100 kilograms Robert Oppenheimer had originally estimated
would be necessary to make a bomb.
e demonstration proved the basic
principle of electromagnetic separation even as it dramatized the method’s
monumental prodigality: Lawrence was proposing to separate uranium
atom by individual atom.
Magnetic field perpendicular to plane of drawing
Enlarging the equipment, increasing the accelerating voltage, multiplying
the number of sources and collectors set side by side between the poles of
the same magnet were obvious ways to improve output and efficiency.
Lawrence had committed his time to winning the war; now he committed
his beautiful new 184-inch cyclotron.
Instead of cyclotron dees he had D-
shaped mass-spectrometer tanks installed between the pole faces of its
4,500-ton magnet.
Making the new instrument work, through the spring
and summer of 1942, solved the most difficult design problems.
It acquired a
name along the way: calutron, another tron from the University of Cali
fornia.
To separate 100 grams—about 4 ounces—of U235 per day, Lawrence
estimated in the autumn of 1942, would require some 2,000 4-foot calutron
tanks set among thousands of tons of magnets.
If a bomb needed 30
kilograms—66 pounds—of U235 for reasonable efficiency, as the Berkeley
summer study group had just worked out, 2,000 such calutrons could enrich
material enough for one bomb core every 300 days.
at assumed the
system worked reliably, which so far its laboratory predecessors had hardly
done.
Yet in 1942 electromagnetic separation still looked so much more
promising to James Bryant Conant than either the plutonium approach or
gaseous barrier diffusion that he had offered up for debate the possibility of
pursuing it exclusively.
Lawrence was self-confident but not foolhardy; he
insisted that the two dark horses should continue to run the race alongside
the favorite.
Groves was less impressed.
So was the first Lewis committee that had
visited Chicago and Berkeley when Fermi was building CP-1 in the winter of
1942.
e Lewis committee judged gaseous diffusion the best approach
because it was most like existing technology—diffusion was a phenomenon
familiar to petroleum engineers and a gaseous-diffusion plant would be
essentially an enormous interconnected assemblage of pipes and pumps.
Electromagnetic separation by contrast was a batch process untested at such
monumental scale; Berkeley planned a system of 4-foot tanks set vertically
between the pole faces of large square electromagnets, two tanks to a gap
and a total of 96 tanks per unit.
To reduce the amount of iron needed for the
magnet cores the arrangement would be not rectangular but oval, like a
racetrack:
And racetrack it was called, though its official designation was Alpha.
Berkeley could promise only 5 grams of enriched uranium per day per
racetrack, but Groves thought 2,000 tanks well beyond Stone & Webster’s
capability and cut the number back to 500, reasoning, as Lawrence recalled
later, “that the art and science of the process would go forward and that by
the time the plant was built substantially higher production rates would be
assured.
”1878 Five grams per day per racetrack with only five racetracks
would mean 1,200 days per 30-kilogram bomb even if the Alpha calutrons
produced nearly pure U235, which they did not—their best production was
around 15 percent.
Groves counted on improvements and forged ahead.
He had to begin building before he knew precisely what to build.
He
worked from the general to the particular, from outline to detail.
Fully six
months before he decided how many calutrons to authorize, his
predecessors, Colonel James Marshall and Lieutenant Colonel Kenneth
Nichols, had moved to solve one serious problem of supply.
e United
States was critically short of copper, the best common metal for winding the
coils of electromagnets.
For recoverable use the Treasury offered to make
silver bullion available in copper’s stead.
e Manhattan District put the
offer to the test, Nichols negotiating the loan with Treasury Undersecretary
Daniel Bell.
“At one point in the negotiations,” writes Groves, “Nichols...
said that they would need between five and ten thousand tons of silver.
is
led to the icy reply: ‘Colonel, in the Treasury we do not speak of tons of
silver; our unit is the Troy ounce.’ ”1879 Eventually 395 million troy ounces of
silver—13,540 short tons—went off from the West Point Depository to be
cast into cylindrical billets, rolled into 40-foot strips and wound onto iron
cores at Allis-Chalmers in Milwaukee.
Solid-silver bus bars a square foot in
cross section crowned each racetrack’s long oval.
e silver was worth more
than $300 million.
Groves accounted for it ounce by ounce, almost as
carefully as he accounted for the fissionable isotope it helped separate.
Stone & Webster had only foundation drawings in hand when its
contractors broke ground for the first Alpha racetrack building on February
18, 1943.
Groves had initially approved three buildings to house five
racetracks.
In March he authorized a second, Beta stage of half-size
calutrons, seventy-two tanks on two rectangular tracks, that would further
enrich the eventual Alpha output to 90 percent U235.
Alpha and Beta
buildings alone eventually covered more area in the valley between Pine and
Chestnut ridges than would twenty football fields.
Racetracks were mounted
on second floors; first floors held monumental pumps to exhaust the
calutrons to high vacuum, more cubic feet of vacuum than the combined
total volume pumped down everywhere else on earth at that time.
Eventually the Y-12 complex counted 268 permanent buildings large and
small—the calutron structures of steel and brick and tile, chemistry
laboratories, a distilled water plant, sewage treatment plants, pump houses, a
shop, a service station, warehouses, cafeterias, gatehouses, change houses
and locker rooms, a paymaster’s office, a foundry, a generator building, eight
electric substations, nineteen water-cooling towers—for an output measured
in the best of times in grams per day.
An inspection trip in May 1943 awed
even Ernest Lawrence.
By August, twenty thousand construction workers swarmed over the
area.
1880, 1881 An experimental Alpha unit saw successful operation.
Lawrence was urging Groves then to double the Alpha plant.
With ten Alpha
racetracks instead of five he estimated he could separate half a kilogram of
U235 per day at 85 percent enrichment.
An Army engineer’s less exuberant
summary, written six days aer Lawrence’s, predicted 900 grams per month
with existing Alpha and Beta stages beginning in November 1943, for a total
of 22 kilograms of bomb-grade U235 in the first year of operation.
Faced
with new estimates from Los Alamos that summer that an efficient uranium
gun would probably require 40 kilograms—88 pounds—of the rarer
uranium isotope, Groves bought Lawrence’s proposal.
1882 e doubling
would add four new 96-tank tracks of advanced design designated Alpha II
and a proportionate number of Beta tracks, at a cost of $150 million more
than the $100 million already authorized.
If everything worked at Y-12,
Groves justified his proposal to the Military Policy Committee, he would
then have a 40-kilogram bomb core around the beginning of 1945.
e Army had contracted with Tennessee Eastman, a manufacturing
subsidiary of Eastman Kodak, to operate the electromagnetic separation
plant.
1883 By late October 1943, when Stone & Webster finished installing
the first Alpha racetrack, the company had assembled a work force of 4,800
men and women.
ey were trained to run and maintain the calutrons—
without knowing why—twenty-four hours a day, seven days a week.
e big square racetrack magnets wrapped with silver windings were
encased in boxes of welded steel.
Oil that circulated through the boxes was
supposed to insulate the windings and carry heat away.
e first magnets
tested at the end of October leaked electricity.
If moisture in the circulating
oil was shorting out the coils, the normal heat of operation would correct
the problem by evaporating the water.
Tennessee Eastman pushed on.
Vacuum leaks in the calutron tanks were numerous and hard to find—one
supervisor remembers spending most of a month looking for one leak.
1884
Inexperienced operators had trouble striking and maintaining a steady ion
beam.
Groves recalls that the powerful magnets unexpectedly “moved the
intervening tanks, which weighed some fourteen tons each, out of position
by as much as three inches....
e problem was solved by securely welding
the tanks into place, using heavy steel tie straps.
Once that was done, the
tanks stayed where they belonged.” 1885
e magnets dried out but continued to short.
Something was seriously
wrong.
Early in December Tennessee Eastman shut the entire 96-tank
racetrack down.
e company’s engineers would have to break open one of
the windings and examine it.
at was major trauma; the unit must then be
returned to Allis-Chalmers and rebuilt.
e inspectors found disaster: two major troubles.
“e first lay in the
design,” writes Groves, “which placed the heavy current-carrying silver
bands too close together.1886 e other lay in the excessive amount of rust
and other dirt particles in the circulating oil.
ese bridged the too narrow
gap between the silver bands and resulted in shorting.” Groves arrived
seething from Washington on December 15 to view the remains.
e
design’s inadequacy forced the general to order all forty-eight magnets
hauled back to Milwaukee to be cleaned and rebuilt.
e second Alpha track
would not come on line until mid-January 1944.
ey would lose at least a
month of production.
Tennessee Eastman’s 4,800 employees reported for work in the shambles
of gloomy halls.
Rather than lose them from boredom the company
scheduled classes, conferences, lectures, motion pictures, games.
Serious
men in double-breasted suits scouted the state for chess and checker sets.
At
the end of 1943 Y-12 was dead in the water with hardly a gram of U235 to
show for all its enormous expense.
* * *
Gaseous-diffusion research had progressed at Columbia University since
John Dunning and Eugene Booth had first demonstrated measurable U235
separation in November 1941.
By the spring of 1942 Harold Urey could note
in a progress report that “three methods for the separation of the uranium
isotopes have now reached the engineering stage.
ey are the English and
the American diffusion methods, and the centrifuge method.” With the
authorization of the full-scale plant Dunning’s staff, which had grown to
include about ninety people, increased in early 1943 to 225.1887 , 1888 Franz Simon’s diffusion method would have operated at low gas pressures and in
incremental ten-unit stages but required extremely large pumps; Columbia
designed a high-pressure system with more conventional pumps, a
continuous, interconnected cascade of some four thousand stages.
In a
postwar memoir Groves reviews the design, which was both reliably simple
and expensively tedious:
e method was completely novel.
It was based on the theory that if
uranium gas was pumped against a porous barrier, the lighter molecules
of the gas, containing U-235, would pass through more rapidly than the
heavier U-238 molecules.
e heart of the process was, therefore, the
barrier, a porous thin metal sheet or membrane with millions of
submicroscopic openings per square inch.
ese sheets were formed into
tubes which were enclosed in an airtight vessel, the diffuser.
As the gas,
uranium hexafluoride, was pumped through a long series, or cascade, of
these tubes it tended to separate, the enriched gas moving up the cascade
while the depleted moved down.
However, there is so little difference in
mass between the hexafluoride of U-238 and U-235 that it was impossible
to gain much separation in a single diffusion step.
at was why there had
to be several thousand successive stages.1889
In schematic cross section the stages looked like this:
“Further development of barriers is needed,” Urey had concluded in his
progress report, “but we now feel confident that the problem can be
solved.
”1890 It had not been solved when Groves committed the Manhattan
Project to a $100 million gaseous-diffusion plant, however; no practical
barrier was yet in hand.
e American process required finer-pored material
than the British; the material also had to be rugged enough to withstand the
higher pressure of the heavy, corrosive gas.
Columbia had been experimenting with copper barriers but abandoned
them late in 1942 in favor of nickel, the only common metal that resisted
hexafluoride corrosion.
Compressed nickel powder made a suitably rugged
but insufficiently fine-pored barrier material; electro-deposited nickel mesh
made a suitably fine-pored but insufficiently rugged alternative.
A self-
educated Anglo-American interior decorator, Edward Norris, had devised
the electro-deposited mesh originally for a new kind of paint sprayer he
invented; he joined the Columbia project in 1941 and worked with chemist
Edward Adler, a young Urey protégé, to adapt his invention to gaseous
diffusion.
e resulting Norris-Adler barrier in its nickel incarnation
seemed in January 1943 to be improvable eventually to production quality,
whereupon Columbia began installing a pilot plant in the basement of
Schermerhorn Laboratory and Groves authorized full-scale barrier
production.
e Houdaille-Hershey Corporation took on that assignment
on April 1, the day the gates began operating at Oak Ridge, planning a new
factory for the purpose in Decatur, Illinois.
Suitable barrier material was the worst but not the only problem
Columbia studied and Groves engineered.
Hex attacked organic materials
ferociously: not a speck of grease could be allowed to ooze into the gas
stream anywhere along the miles and miles of pipes and pumps and barriers.
Pump seals therefore had to be devised that were both gastight and
greaseless, a puzzle no one had ever solved before that required the
development of new kinds of plastics.
(e seal material that eventually
served at Oak Ridge came into its own aer the war under the brand name
Teflon.) A single pinhole leak anywhere in the miles of pipes would
confound the entire system; Alfred O.
Nier developed portable mass
spectrometers to serve as subtle leak detectors.
Since pipes of solid nickel
would exhaust the entire U.S.
production of that valuable resource, Groves
found a company willing to nickel-plate all the pipe interiors, a difficult new
process accomplished by filling the pipes themselves with plating solution
and rotating them as the plating current did its work.
e plant that would hold thousands of diffusion tanks, the largest of
them of 1,000 gallon capacity, would be necessarily monumental: four
stories high, almost half a mile long in the shape of a U, a fih of a mile
wide, 42.6 acres under roof, some 2 million square feet, more than twice the
total ground area of Y-12’s Alpha and Beta buildings.
K-25, as the gaseous-
diffusion complex was designated, needed more than a narrow ridge valley.
e building and operating contractors, Kellex and Union Carbide, found a
relatively flat site along the Clinch River at the southwestern end of the
reservation; the first surveying, for the coal-fired power plant needed to run
the factory, began on May 31, 1943.
Rather than designing and setting thousands of different columns for
footings the construction contractors leveled and compacted the entire K-25
foundation area, plowing, drying and moving in the process nearly 100,000
cubic yards of red clay.
at took months; the first concrete—200,000 cubic
yards—was not poured until October 21.
By then the continuing failure to
develop an adequate barrier material had led Groves to decide to lop off the
unfinished plant’s upper stages and limit its enrichment potential to less
than 50 percent U235—it would have been capable of taking natural
uranium all the way to pure U235 with its full complement of diffusers—and
to use this enriched material to feed the Beta calutrons at Y-12.
Kellex succeeded in devising a promising new barrier material in the
autumn of 1943 that combined the best features of the Norris-Adler barrier
and the compressed nickel-powder barrier.
e problem then was what to
do about the Houdaille-Hershey plant under construction in Decatur, which
was designed to produce Norris-Adler.
Should it be stripped and reequipped
to manufacture the new barrier at the price of some delay in starting up K-
25?
Or should the several barrier-development teams make a final concerted
effort to improve Norris-Adler to production quality?
Over these significant
questions Groves and Harold Urey violently clashed.
Kellex wanted to strip the Houdaille-Hershey plant and convert it,
preferring delay to the risk of failure.
Urey thought abandoning the Norris-
Adler barrier would mean forgoing the production of U235 by gaseous
diffusion in time to shorten the war.
In which case he saw no reason to
continue building K-25; its high priority, he argued, would even hinder the
war effort by displacing more immediately useful production.
Groves decided to submit the dispute to an unusual review committee: the
experts who had worked on gaseous diffusion in England.
With the renewal
of interchange between the British and American atomic bomb programs
that autumn the British had arranged to send a delegation to work in
America.
Led by Wallace Akers of ICI, the group included Franz Simon and
Rudolf Peierls.
It met with both sides—Kellex and Columbia—on December
22 and then settled in to review American progress.
e participants reconvened early in January 1944.
e new barrier, the
British concluded, would probably be superior eventually to the Norris-
Adler, but they thought the months of research on the Norris-Adler must
count decisively in its favor if time was of the essence.
e new barrier had
been manufactured so far only by hand in small batches.
Yet K-25 would
require acres of it to fill the planned 2,892 stages of the diffusion plant’s
cascade.1891
en Kellex set a trap: it proposed to produce the new barrier by hand by
piecework—thousands of workers each duplicating the simple laboratory
process Kellex had initially devised—and claimed that by doing so it could
match or beat the Norris-Adler production schedule.
When the British had
recovered from their surprise at the novelty of the proposal they signaled
their preference for the new barrier by agreeing that if production was
possible it ought to be pursued.
at agreement sprang the trap; with the
British implicitly committed, the American engineers revealed that they
could only manufacture the new barrier by stripping the Houdaille-Hershey
plant and forgoing Norris-Adler production entirely.
Groves in any case had already decided, the day before the January
meeting, to switch over to the new barrier; the British review then simply
ratified his decision.
By changing barriers rather than abandoning gaseous
diffusion he confirmed what many Manhattan Project scientists had not yet
realized: that the commitment of the United States to nuclear weapons
development had enlarged from the seemingly urgent but narrow goal of
beating the Germans to the bomb.
Building a gaseous-diffusion plant that
would interfere with conventional war production, would eventually cost
half a billion dollars but would almost certainly not contribute significantly
to shortening the war meant that nuclear weapons were thenceforth to be
counted a permanent addition to the U.S.
arsenal.
Urey saw the point and
withdrew; “from that time forward,” write his colleague biographers, “his
energies were directed to the control of atomic energy, not its
applications.
”1892
* * *
Twelve days aer Enrico Fermi proved the chain reaction in Chicago on
December 2, 1942, Groves had assembled a list of criteria for a plutonium
production area and definitely and finally ruled out Tennessee.
“e Clinton
site...
was not far from Knoxville,” he comments, “and while I felt that the
possibility of serious danger was small, we could not be absolutely sure; no
one knew what might happen, if anything, when a chain reaction was
attempted in a large reactor.
If because of some unknown and unanticipated
factor a reactor were to explode and throw great quantities of highly
radioactive materials into the atmosphere when the wind was blowing
toward Knoxville, the loss of life and the damage to health in the area might
be catastrophic.” Such an accident might “wipe out all semblance of security
in the project,” Groves could imagine, and it might render the
electromagnetic and gaseous-diffusion plants “inoperable.” 1893 Better to site
plutonium production somewhere far away.
e production piles needed plentiful electricity and water for blowing
and cooling the helium that was planned to cool them.
For safety they
needed space.
ose criteria suggested the great river systems of the Far
West, particularly the Columbia River basin.
Groves sent out an officer who
would administer the plutonium reservation along with the civilian engineer
who would supervise construction for Du Pont.
Besides picking the site he
wanted the two men to get used to working together.
ey did, agreeing on a
promising location in south-central Washington State, and arrived back in
Groves’ office on New Year’s Eve to report.
e general received a real estate
appraisal on January 21, 1943.
1894 By then he had already personally walked
the ground.
Eastward of the Cascade Range, twenty air miles east of the city of
Yakima, the blue, cold, fast-running Columbia River bends east, then
northeast, abruptly ninety degrees southeast and finally due south through a
flat, arid scrubland on its last excursion toward the continental interior
before it makes its great bend below Pasco to course directly westward two
hundred fiy miles to the sea.
Even that far inland the river is wide and deep
and veined in season with salmon, but the sandy plain surrounding wins
little of the river’s water and the barrier of the Cascades denies it more than
six inches a year of rain.
e site Groves’ representatives discovered, and Groves acquired at the
end of January at a cost of about $5.1 million, was contained within the
eastward excursion of the Columbia: some 500,000 acres, about 780 square
miles, devoted primarily to sheep grazing but varied with a few irrigated
orchards and vineyards and a farm or two thriving in wartime on irrigated
crops of peppermint.
Temperatures ranged from a maximum of 114° in the
long, dry summers to rare −27° winter lows.
Roads were sparse on the
roughly circular thirty-mile tract.
A Union Pacific railroad line crossed one
corner; a double electric power line of 230 kilovolts traversed the northwest
sector on its way from Grand Coulee Dam to Bonneville Dam.
Gable
Mountain, an isolated basalt outcropping that rose five hundred feet above
the sedimentary plain a few miles southwest of the ninety-degree river bend,
divided the riverside land at the bend from the interior.
Midway down the
tract where a ferry crossed the Columbia, a half-abandoned riverside village,
population about 100, supplied a base of buildings and gave the Hanford
Engineer Works its name.
1895
Groves could hardly build Hanford until he knew more about the plant
that would go there.
It was clear that he would need enormous quantities of
concrete to shield the production piles and chemical processing buildings;
his Hanford engineer searched out accessible beds of gravel and aggregate to
quarry.
An accident might release radioactivity into the air; that called for
thorough meteorological work.
e river water needed study; so did the
river’s valuable salmon, to see how they would take to mild doses of
transient radioactivity from pile discharge flow.
Roads had to be paved,
power sources tapped, hutments and barracks built for tens of thousands of
construction workers.
What had come up once again for discussion early in 1943 was how the
plutonium production piles—the Du Pont engineers were beginning to call
them reactors—should be cooled.
Crawford Greenewalt, in charge of
plutonium production for Du Pont, continued to plan for helium cooling
because the noble gas had no absorption cross section at all for neutrons.
But it would need to be pumped through the piles under high pressure; that
would require large, powerful compressors Greenewalt was not at all sure he
had time to build.
Enormous steel tanks would be needed to contain the gas;
they would have to allow access to the pile but still remain airtight, a
formidable challenge to engineer or even simply to weld.
Eugene Wigner came to the project’s rescue.
Fermi had found k for CP-1
higher than he expected.
e Stagg Field pile had been assembled largely
from uranium oxide.
Its graphite had varied in quality, improving along the
way.
A production pile of pure uranium metal and high-quality graphite
would find k higher yet—high enough, Wigner calculated, to make water
cooling practical.
Wigner’s team designed a 28- by 36-foot graphite cylinder lying on its side
and penetrated through its entire length horizontally by more than a
thousand aluminum tubes.
Two hundred tons of uranium slugs the size of
rolls of quarters would fill these tubes.
Chain-reacting within 1,200 tons of
graphite, the uranium would generate 250,000 kilowatts of heat; cooling
water pumped through the aluminum tubes around the uranium slugs at the
rate of 75,000 gallons per minute would dissipate that heat.
e slugs would
not go naked into the torrent; Wigner intended that they also should be
separately sheathed in aluminum—canned.
When they had burned long
enough—100 days—to transmute about 1 atom in every 4,000 into
plutonium the irradiated slugs could be pushed out the back of the pile
simply by loading fresh slugs in at the front.
1896, 1897 e hot slugs would fall into a deep pool of pure water that would safely confine their intense but
short-lived fission-product radioactivity.
Aer 60 days they could be fished
out and carted off for chemical separation.
e Wigner design was elegantly simple.
Greenewalt saw engineering
problems—in particular the question whether corrosion of the aluminum
tubes would block the flow of cooling water—and studied helium and water
side by side until the middle of February.
Corrosion studies were promising.
“With water of high purity,” writes Arthur Compton, “the evidence indicated
that no serious difficulties from this source should arise.
”1898 Greenewalt
opted then for water cooling.
Wigner, whom Leo Szilard calls “the
conscience of the Project from its early beginnings to its very end,” who
worried constantly about German progress, wondered angrily why it had
taken Du Pont three months to see the value of a system he and his group
had judged superior in the summer of 1942.
1899
With that basic decision construction could begin at Hanford.
ree
production piles would go up at six-mile intervals along the Columbia River,
two upstream and one downstream of its ninety-degree bend.
Ten miles
south, screened behind Gable Mountain, Du Pont would build four
chemical-separation plants paired at two sites.
e former town of Hanford
would become a central construction camp serving all five construction
areas.
e work proceeded slowly, dogged by recruiting problems.
e nation at
war had moved beyond full employment to severe labor shortages and men
and women willing to camp out on godforsaken scrubland far from any
major city were hard to find.
Frequent sandstorms plagued the area, writes
Leona Woods, now Leona Marshall aer marrying fellow physicist John
Marshall of Fermi’s staff.
“Local storms were caused by tearing up the desert
floor for roads, and construction sites were suffocating.
Wind-blown sand
covered faces, hair, and hands and got into eyes and teeth....
Aer each
storm, the number of people quitting might be as much as twice the average.
When the storms were at their worst, buses and other traffic came to a stop
until the roads were visible through the greyblack clouds of dust.
”1900 Stoics
who stayed on called the dust “termination powder.”
“e most essential thing to bring with you is a padlock,” a project
recruiting pamphlet ominously announced.
“e next important things are
towels, coat hangers and a thermos bottle.
Don’t bring cameras or guns.” 1901
Hanford, says Marshall, “was a tough town.
ere was nothing to do aer
work except fight, with the result that occasionally bodies were found in
garbage cans the next morning.
”1902 Du Pont built saloons with windows
hinged for easy tear-gas lobbing.
Eventually some 5,000 construction
workers struggled in the desert dust and Du Pont built more than two
hundred barracks to house them.
Meat rationing stopped at the edge of the
reservation; there were no meatless Tuesdays in the vast Hanford mess halls,
a significant enticement for recruiting.
e gray coyotes of the region fed
sleek in turn on rabbits killed by cars and trucks driving the new reservation
roads.
By August 1943 work had begun on the water-treatment plants for the
three piles, capacity sufficient to supply a city of one million people.
Du Pont
released pile-design drawings in Wilmington, Delaware, on October 4 and
the company’s engineers staked out the first pile, 100-B, beside the Columbia
on October 10.
Aer excavating, reports an official history, “work gangs
began to lay the first of 390 tons of structural steel, 17,400 cubic yards of
concrete, 50,000 concrete blocks, and 71,000 concrete bricks that went into
the pile buildings.
1903 Starting with the foundations for the pile and the deep
water basins behind it where the irradiated slugs would be collected aer
discharge, the work crews were well above ground by the end of the year.”
e forty-foot windowless concrete monolith they were building was hollow,
however: installation of B pile would not begin until February 1944.1904
* * *
“ere was a large change of scale from the Chicago to the Hanford piles,”
Laura Fermi remarks.
“As Fermi would have put it, they were different
animals.” 1905 So also were Ernest Lawrence’s behemoth mass spectrometers
and John Dunning’s gaseous-diffusion factory with its 5 million barrier
tubes.
e mighty scale of the works at Clinton and Hanford is a measure of
the desperation of the United States to protect itself from the most serious
potential threat to its sovereignty it had yet confronted—even though that
threat, of a German atomic bomb, proved to be an image in a darkened
mirror.
It is also a measure of the sheer recalcitrance of heavy-metal
isotopes.
Niels Bohr had insisted in 1939 that U235 could be separated from
U238 only by turning the country into a gigantic factory.
“Years later,” writes
Edward Teller, “when Bohr came to Los Alamos, I was prepared to say, ‘You
see...’ But before I could open my mouth, he said, ‘You see, I told you it
couldn’t be done without turning the whole country into a factory.
You have
done just that.’ ” 1906
e monumental scale reveals another desperation as well: how
ambitiously the nation was moving to claim the prize.
And to deny it to
others, even to the British until Winston Churchill turned Franklin
Roosevelt’s head at the conference in Quebec in August 1943, where
Operation Overlord, the 1944 invasion of Europe across the beaches of
Normandy, was planned.
Before then, in June, Groves had demonstrated this
last desperation at its most overweening: he proposed to the Military Policy
Committee that the United States attempt to acquire total control of all the
world’s known supplies of uranium ore.
When the Union Minière refused to
reopen its flooded Shinkolobwe Mine in the Belgian Congo, Groves had to
turn to the British, who owned a significant minority interest in the Belgian
firm, for help; aer Quebec the partnership evolved into an agreement
between the two nations known as the Combined Development Trust to
search out world supplies.
at uranium is common in the crust of the earth
to the extent of millions of tons Groves may not have known.
In 1943, when
the element in useful concentrations was thought to be rare, the general,
acting on behalf of the nation to which he gave unquestioning devotion,
exercised himself to hoard for his country’s exclusive use every last pound.
He might as well have tried to hoard the sea.
* * *
Work toward an atomic bomb had begun in the USSR in 1939.
A thirtysix-
year-old nuclear physicist, Igor Kurchatov, the head of a major laboratory
since his late twenties, alerted his government then to the possible military
significance of nuclear fission.
Kurchatov suspected that fission research
might be under way already in Nazi Germany.
Soviet physicists realized in
1940 that the United States must also be pursuing a program when the
names of prominent physicists, chemists, metallurgists and mathematicians
disappeared from international journals: secrecy itself gave the secret
away.1907
e German invasion of the USSR in June 1941 temporarily ended what
had hardly been begun.
“e advance of the enemy turned everyone’s
thoughts and energies to one single job,” writes Academician Igor Golovin, a
colleague of Kurchatov and his biographer: “to halt the invasion.
Laboratories were deserted.
Equipment, instruments and books were packed
up, and valuable records shipped east for safety.” 1908 e invasion rearranged
research priorities.
Radar now took first place, naval mine detection second,
atomic bombs a poor third.
Kurchatov moved to Kazan, four hundred miles
east of Moscow beyond Gorky, to study defenses against naval mines.
In Kazan at the end of 1941 he heard from George Flerov, one of the two
young physicists in his Moscow laboratory who had discovered the
spontaneous fission of uranium in 1940 and reported their discovery in a
cable to the Physical Review.
1 Flerov had attended an international meeting
of scientists in Moscow in October and heard Peter Kapitza, Ernest
Rutherford’s protege, when asked what scientists could do to help the war
effort, respond in part:
In recent years a new possibility—nuclear energy—has been discovered.
eoretical calculations show that, if a contemporary bomb can for
example destroy a whole city block, an atomic bomb, even of small
dimensions, if it can be realized, can easily annihilate a great capital city
having a few million inhabitants.1909
us recalled to their earlier work, Flerov challenged Kurchatov as he had
already in a similar letter challenged the State Defense Committee that “no
time must be lost in making a uranium bomb.
”1910 e first requirement was
fast-neutron research, he wrote.
e MAUD Report had only just made that
necessity clear to the United States.
Kurchatov disagreed.
Research toward a uranium weapon seemed too far
removed from the immediate necessities of war.
But the Soviet government
in the meantime had assembled an advisory committee that included
Kapitza and the senior Academician Abram Joffe, Kurchatov’s mentor.
e
committee endorsed atomic bomb research and recommended Kurchatov to
head it.
Somewhat reluctantly he accepted.
“So it was that from early 1943 on,” writes his colleague A.
P.
Alexandrov,
“work on this difficult problem was resumed in Moscow under the
leadership of Igor Kurchatov.
1911 Nuclear scientists were recalled from the
front, from industry, from the research institutes which had been evacuated
to the rear.
Auxiliary work began in many places.” Auxiliary work included
building a cyclotron.
Kurchatov moved his institute out of the Soviet capital
to an abandoned farm near the Moscow River in the summer of 1943.
An
artillery range nearby offered an area for explosives testing; “Laboratory No.
2” would be the Soviet Union’s Los Alamos.
By January 1944 Kurchatov had
assembled a staff of only about twenty scientists and thirty support
personnel.
“Even so,” writes Herbert York, “they did experiments and made
theoretical calculations concerning the reactions involved in both nuclear
weapons and nuclear reactors, they began work designed to lead to the
production of suitably pure uranium and graphite, and they studied various
possible means for the separation of uranium isotopes.” 1912 But the Soviet
Bear was not yet fully aroused.
* * *
“e kind of man that any employer would have fired as a troublemaker.”
us Leslie Groves described Leo Szilard in an off-the-record postwar
interview, as if the general had arrived first at fission development and
Szilard had only been a hireling.1913 Groves seems to have attributed
Szilard’s brashness to the fact that he was a Jew.
Upon Groves’ appointment
to the Manhattan Project he almost immediately judged Szilard a menace.
ey proceeded to fight out their profound disagreements hand to hand.
e heart of the matter was compartmentalization.
Alice Kimball Smith,
the historian of the atomic scientists whose husband Cyril was associate
division leader in charge of metallurgy at Los Alamos, defines the
background of the conflict:
If the Project could have been run on ideas alone, says Wigner, no one but
Szilard would have been needed.
Szilard’s more staid scientific colleagues
sometimes had trouble adjusting to his mercurial passage from one
solution to another; his army associates were horrified, and to make
matters worse, Szilard freely indulged in what he once identified as his
favorite hobby—baiting brass hats.
General Groves, in particular, had
been outraged by Szilard’s unabashed view that army
compartmentalization rules, which forbade discussion of lines of research
that did not immediately impinge on each other, should be ignored in the
interests of completing the bomb.
1914
e issue for Szilard was openness within the project to facilitate its work.
“ere is no way of telling beforehand,” he wrote in a 1944 discussion of the
problem, “what man is likely to discover and invent a new method which
will make the old methods obsolete.” 1915 e issue for Groves, to the
contrary, was security.
At first Szilard bent the rules and Groves threatened him.
In late October
1942, while Fermi moved toward building CP-1, Szilard apparently badgered
the Du Pont engineers who arrived in Chicago to take over pile design.
Arthur Compton saw this activity as obstructive but not necessarily
subversive; on October 26 he wired Groves that he had given Szilard two
days TO REMOVE BASE OF OPERATIONS TO NEW YORK.
ACTION BASED ON EFFICIENT
OPERATION OF ORGANIZATION NOT ON RELIABILITY.
ANTICIPATE PROBABLE
RESIGNATION.
1916 Compton did not know his man.
Szilard would not resign,
for the simple reason that he believed he was needed to help beat Germany
to the bomb.
Compton proposed surveillance: SUGGEST ARMY FOLLOW HIS
MOTIONS BUT NO DRASTIC ACTION NOW.
Two days later Compton hurriedly
wired Groves to desist: SZILARD SITUATION STABILIZED WITH HIM REMAINING
CHICAGO OUT OF CONTACT WITH ENGINEERS.
SUGGEST YOU NOT ACT WITHOUT
FURTHER CONSULTATION CONANT AND MYSELF.
1917
Groves had prepared drastic action indeed.
On the stationery of the Office
of the Chief of Engineers, over a signature block reserved for the Secretary
of War, he had draed a letter to the U.S.
Attorney General calling Leo
Szilard an “enemy alien” and proposing that he “be interned for the duration
of the war.
”1918 Compton’s telegram forestalled an ugly arrest and the letter
was never signed or sent.
1919
But the incident raised the issue of Szilard’s loyalty and prejudiced Groves
implacably against him.
Szilard responded forthrightly; he assembled a large
collection of documents from the 1939–40 period demonstrating his part in
carrying the news of fission to Franklin Roosevelt and, pointedly, his efforts
to enforce voluntary secrecy among physicists in the United States, Britain
and France.
Compton, waffling, sent the documents to Groves in mid-
November with an implicit endorsement of Szilard’s stand.
e first Groves-
Szilard confrontation thus ended in stalemate.
Szilard saw how much raw
power Groves commanded.
Groves learned how deep were Szilard’s roots in
the evolution of atomic energy research and perhaps also that men he
considered vital to the project—Fermi, Teller, Wigner—were Szilard
colleagues of long standing and would have to be taken into account.
As political dissidents have done in the Soviet Union, Szilard embarked
next on a careful campaign to negotiate changes by insisting meticulously on
the enforcement of his legal rights.
His opening sally came December 4, two
days aer Fermi proved the chain reaction.
In a quiet memorandum to
Arthur Compton he noted that the official responsible for handling NDRC
patents had requested patent applications “for inventions relating to the
chain reaction.” at raised the question, Szilard wrote, of how to deal with
inventions “made and disclosed before we had the benefit of the financial
support of the government.
”1920 He and Fermi would be glad to file a joint
application, but only if they could be sure they retained their rights to their
earlier separate inventions.
e memorandum continues in this
straightforward style until its final paragraph, which throws down the
gauntlet:
My present request clearly represents a change of [my] attitude with
respect to patents on the uranium work, and I would appreciate an
opportunity to explain to you and also to the government agency which
may be involved, my reasons for it.
Previously Szilard had believed he would have equal voice in fission
development.
Since he had now been compartmentalized, his freedom of
speech restrained, his loyalty challenged, he was prepared to actuate the only
leverage at hand, his legal right to his inventions.
Compton sent Szilard’s request to Lyman Briggs, whose responsibilities
within the OSRD included patent matters; Briggs thought the Army ought
to handle it.
1921 Szilard waited until the end of December, heard nothing
and advanced further into the field.
In a second memorandum he told
Compton he wanted to apply for a patent on “the basic inventions which
underlie our work on the chain reaction on unseparated uranium...
which
were made before government support for this research was
forthcoming.” 1922 e patent could be registered in his name alone or jointly
with Fermi; he would be willing “to assign this patent at this time to the
government for such financial compensation as may be deemed fair and
equitable.” e memorandum mentions no amount; according to Army
security files Szilard asked for $750,000.1923 But the issue was not
compensation; the issue was representation:
I wish to take this opportunity to mention that the question of patents was
discussed by those who were concerned in 1939 and 1940.
At that time it
was proposed by the scientists that a government corporation should be
formed which would look aer the development of this field and...
be
the recipient of the patents.
It was assumed that the scientists would have
adequate representation within this government owned corporation....
In the absence of such a government owned corporation in which the
scientists can exert their influence on the use of funds, I do not now
propose to assign to the government, without equitable compensation,
patents covering the basic inventions.
Burdened by Manhattan Project security, with Du Pont taking over
plutonium production and the Army moving hundreds of thousands of
cubic yards of earth in unprecedented construction, Leo Szilard was
advancing singlehandedly to attempt to extricate the process of decision
from governmental restraints and to return it to the hands of the atomic
scientists.
Compton understood the extent of the challenge.
He sent Szilard’s two
memoranda directly to Conant, whose office received them on January 11,
1943.
“Szilard’s case is perhaps unique,” Compton wrote the NDRC
chairman, “in that for a number of years the development of this project has
continuously occupied his primary attention....
ere is no doubt that he is
among the few to whom the United States Government can look for
establishing basic claims for invention.
e matter is thus one of real
importance to our Government.” 1924
Before Washington could respond Szilard had to fight off a harassing
attack from the flank.
It strengthened his resolve.
He discovered that a
French patent filed originally by Frédéric Joliot’s group had been published
in Australia and he and Fermi had missed the deadline for filing challenges.
Some of their claims overlapped the French work.
“is is, I am afraid, an
irreparable loss,” he told Compton.
He had now started writing down his
own inventions, he said, and hoped to file a number of patents in the near
future.
Until he had done so he wanted to be removed from the payroll of
the University of Chicago to avoid legal complications.
In the meantime he
would toil on once again as a free volunteer: “It would not be my intention
to interrupt or slow down the work which I am doing in the laboratory at
present.
”1925
Conant bumped Compton’s letter up to Bush, who answered it personally
and to the point with Yankee canniness.
Inventions scientists made aer
joining the project belonged to the project, Bush told Compton; unless
Szilard had disclosed his previous inventions to the University of Chicago at
the time of his employment he had only a very short leg to stand on, if any at
all.
Genially the OSRD director outlined the proper legal procedure for
secret patent filings and then kicked at the leg Szilard had le: “It is my
understanding that none of this procedure has been gone through with in
the case of Dr.
Szilard.” Bush either did not understand or chose to
misunderstand Szilard’s idea of an autonomous organization of scientists to
guide nuclear energy development: “I gather that Dr.
Szilard is particularly
anxious that the proceeds arising from his early activity in invention in this
field, if such eventuate, should in some way become available for the
furtherance of scientific research.” 1926 He thought that was admirable, but he
also thought it had nothing to do with the government.
Nor did he intend
that it should.
By the time Bush’s letter reached Compton the Met Lab director had gone
another round with Szilard.
Szilard asked for a raise based upon the value to
the project of his inventions.
Compton took the position that Szilard had
signed over all his rights to his inventions to the government for as long as
he was in the government’s employ.
Szilard would not sign a renewal
contract under those terms.
Trying to keep him aboard, Compton proposed
raising his salary from $550 to $1,000 a month on the basis that the higher
level was “comparable with the other original sponsors of this project,
Messrs.
Fermi and Wigner.” 1927 at might have been acceptable to Szilard,
since it tacitly acknowledged the special worth of the three physicists’
participation, including presumably their early inventions, but Compton
had to clear it with Conant.
Until the arrangement was cleared and a new
contract signed Szilard would remain off the payroll.
Compton reported Bush’s response to Szilard in late March.
ere matters
stood until early May, when Szilard with restrained exasperation proposed
to proceed with filing patent applications.
He asked that Groves designate
someone to act as his legal adviser.
e Army general supplied a Navy
captain, Robert A.
Lavender, who was attached to the OSRD in Washington,
and Szilard met frequently with Lavender in the spring and early summer to
discuss his claims.
Somewhere along the way Groves put Szilard under surveillance.
e
brigadier still harbored the incredible notion that Leo Szilard might be a
German agent.
e surveillance was already months old in mid-June when
the MED’s security office suggested discontinuing it.
Groves rejected the
suggestion out of hand: “e investigation of Szilard should be continued
despite the barrenness of the results.
One letter or phone call once in three
months would be sufficient for the passing of vital information and until we
know for certain that he is 100% reliable we cannot entirely disregard this
person.
”1928 He apparently equated disagreement with disloyalty and scaled
the ratio of the two conditions directly: anyone who caused him as much
pain as Leo Szilard must be a spy.
It followed that he ought to be watched.
e surveillance of an innocent but eccentric man makes gumshoe
comedy.
Szilard traveled to Washington on June 20, 1943, and in preparation
for the visit an Army counterintelligence agent reviewed his file:
e surveillance reports indicate that Subject is of Jewish extraction, has a
fondness for delicacies and frequently makes purchases in delicatessen
stores, usually eats his breakfast in drug stores and other meals in
restaurants, walks a great deal when he cannot secure a taxi, usually is
shaved in a barber shop, speaks occasionally in a foreign tongue, and
associates mostly with people of Jewish extraction.
1929 He is inclined to be
rather absent minded and eccentric, and will start out a door, turn around
and come back, go out on the street without his coat or hat and frequently
looks up and down the street as if he were watching for someone or did
not know for sure where he wanted to go.
Armed with these profundities a Washington agent observed the Subject
arriving at the Wardman Park Hotel at 2030 hours—8:30 P.M.—on June 20
and composed a contemporary portrait:
Age, 35 or 40 yrs; height, 5’6”; weight, 165 lbs; medium build; florid
complexion; bushy brown hair combed straight back and inclined to be
curly, slight limp in right leg causing droop in right shoulder and receding
forehead.
He was wearing brown suit, brown shoes, white shirt, red tie
and no hat.
1930
Szilard worked the next morning at the Carnegie Institution with Captain
Lavender.
Wigner arrived at the Wardman Park for an overnight stay (“Mr.
Wigner is approximately 40 years of age, medium build, bald head, Jewish
features and was conservatively dressed”) and the two Hungarians, both of
them presumably with justice on their minds, went off for a tour of the
Supreme Court (the cabbie “said that they did not talk in a foreign tongue
and there was nothing in their conversation to attract his attention....
1931
He said they more or less gave him the impression that they were ‘on a lark’ ”
).
In the evening they sat “on a bench by the [hotel] tennis courts where both
pulled off their coats, rolled up their sleeves and talked in a foreign language
for some time.”
Wigner checked out early in the morning; Szilard took a cab to the Navy
Building at 17th and Constitution Avenue, “entered the reception room...
and told one of the ladies that he wished to see Commander Lewis Strauss
about personal business.
He stated that he had an appointment....
He also
told the lady that he was a friend of Commander Strauss’ and was interested
in getting into a branch of the Navy.” e Naval Research Laboratory had
continued work on nuclear power for submarine propulsion independently
of the Manhattan Project and that institution may have been the one Szilard
had in mind.
Or he may have been practicing misdirection.
Strauss took him
to lunch at the Metropolitan Club and apparently discouraged him from
transferring; back at his hotel he wired Gertrud Weiss that he expected to
arrive at the King’s Crown at 8:30 P.M.
and le that aernoon for New York.
Since he worked for Vannevar Bush, Lavender was hardly a disinterested
consultant; when he met again with Szilard on July 14 he informed the
physicist that his documents “failed to disclose an operable pile,” meaning
that in his opinion Szilard could not claim a patentable invention.1932 (Ten
years aer the end of the war Szilard and Fermi won a joint patent for their
invention of the nuclear reactor.) Szilard realized then, if not before, that he
needed private counsel and asked that an attorney who could act in his
behalf be cleared.
e battle was almost decided.
Szilard retreated to New York.
He
negotiated now not only with Lavender but with Army Lieutenant Colonel
John Landsdale, Jr., Groves’ chief of security.
In an October 9 letter to
Szilard, Groves summed up the blunt exchange over which the three men
bargained: “You were assured [by Lavender and Landsdale] that as soon as
you were able to convey full rights [to any inventions made prior to
government employment], negotiations would be entered into with a view to
acquisition by the Government of any rights you may have and your
reemployment on Government contracts....
I repeat this assurance.” 1933
at is, Szilard could trade his patent rights, if any, for the privilege of
working to beat the Germans to the bomb.
Groves and Szilard arranged a temporary truce—the general may have
imagined it was a surrender—at a meeting in Chicago on December 3.
1934
e Army agreed to pay Szilard $15,416.60 to reimburse him for the twenty
months when he worked unpaid and out-of-pocket at Columbia and for
lawyers’ fees.
e general had attempted several times to force Szilard to sign a
document promising “not to give any information of any kind relating to the
project to any unauthorized person.
”1935 Szilard had consistently agreed
verbally to that restriction and just as consistently refused as a matter of
honor to sign.
He meant to continue protesting and on January 14, 1944, he
began again with a three-page letter to Vannevar Bush.
He knew fieen
people, he told Bush, “who at one time or another felt so strongly about
[compartmentalization] that they intended to reach the President.” 1936 e
central issue as always was freedom of scientific speech: “Decisions are oen
clearly recognized as mistakes at the time when they are made by those who
are competent to judge, but...
there is no mechanism by which their
collective views would find expression or become a matter of record.”
In this letter for the first time Szilard emphasized a purpose to his urgency
beyond beating the Germans to the bomb: that the bomb might be used and
become grimly known.
If peace is organized before it has penetrated the public’s mind that the
potentialities of atomic bombs are a reality, it will be impossible to have a
peace that is based on reality....
Making some allowances for the further
development of the atomic bomb in the next few years...
this weapon
will be so powerful that there can be no peace if it is simultaneously in the
possession of any two powers unless these two powers are bound by an
indissoluble political union....
It will hardly be possible to get political
action along that line unless high efficiency atomic bombs have actually
been used in this war and the fact of their destructive power has deeply
penetrated the mind of the public.
Which was the explanation Szilard now gave for challenging the Army and
Du Pont: “is for me personally is perhaps the main reason for being
distressed by what I see happening around me.”
Bush insisted in return that all was well.
“I feel that the record when this
effort is over,” he wrote Szilard, “will show clearly that there has never at any
time been any bar to the proper expression of opinion by scientists and
professional men within their appropriate sphere of activity in this whole
project.
”1937 But he was willing to meet with Szilard if that was what the
physicist wanted.
In February, preparing for that meeting, Szilard draed
forty-two pages of notes.
Much in those notes is specific and local; here and
there basic issues are joined.
Since invention is unpredictable, Szilard writes, “the only thing we can do
in order to play safe is to encourage sufficiently large groups of scientists to
think along those lines and to give them all the basic facts which they need
to be encouraged to such activity.
is was not done in the past [in the
Manhattan Project] and it is not being done at present.” 1938 He tracked the
consequences of the government’s policies of restriction:
e attitude taken toward foreign born scientists in the early stages of this
work had far reaching consequences affecting the attitude of the
American born scientists.
1939 Once the general principle that authority
and responsibility should be given to those who had the best knowledge
and judgment is abandoned by discriminating against the foreign born
scientists, it is not possible to uphold this principle with respect to
American born scientists either.
If authority is not given to the best men
in the field there does not seem to be any compelling reason to give it to
the second-best men and one may give it to the third- or fourth- or fih-
best men, whichever of them appears to be the most agreeable on purely
subjective grounds.
Wigner’s early discouragement was an “incalculable loss,” Szilard thought;
the fact that Fermi was excluded from centrifuge development work at
Columbia “visibly affected” him “and he has from that time on shown a very
marked attitude of being always ready to be of service rather than
considering it his duty to take the initiative.”
Finally, Szilard judged the Met Lab moribund, its services rejected and its
spirit broken, and pronounced its epitaph:
e scientists are annoyed, feel unhappy and incapable of living up to
their responsibility which this unexpected turn in the development of
physics has thrown into their lap.
As a consequence of this, the morale has
suffered to the point where it almost amounts to a loss of faith.
e
scientists shrug their shoulders and go through the motions of
performing their duty.
ey no longer consider the overall success of this
work as their responsibility.
In the Chicago project the morale of the
scientists could almost be plotted in a graph by counting the number of
lights burning aer dinner in the offices in Eckhart Hall.
At present the
lights are out.
1940
But Leo Szilard at least was not yet done with protest.
* * *
Enrico Fermi took the initiative at least once during the war.
Perhaps
influenced by the enthusiasm he found at Los Alamos for weapons-making,
he proposed at the time of the April 1943 conference—privately to Robert
Oppenheimer, it appears—that radioactive fission products bred in a chain-
reacting pile might be used to poison the German food supply.1941
e possibility of using radioactive material bred in a nuclear reactor as a
weapon of war had been mentioned by Arthur Compton’s National
Academy of Sciences committee in 1941.
German development of such a
weapon began worrying the scientists at the Met Lab late in 1942, on the
assumption that Germany might be a year or more ahead of the United
States in pile development.1942 If CP-1 went critical in December 1942, they
argued, the Germans might have had time by then to run a pile long enough
to create fiercely radioactive isotopes that could be mixed with dust or liquid
to make radioactive (but not fissionable) bombs.
Germany might then
logically attempt preemptively to attack the Met Lab, if not American cities.
German development of radioactive warfare, another vision in a dark
mirror, seemed to the leaders of the Manhattan Project to require
countering by examination into parallel U.S.
development; the S-l
Committee gave such assignment to a subcommittee consisting of James
Bryant Conant as chairman and Arthur Compton and Harold Urey as
members.
at subcommittee went to work sometime before May 1943,
probably before February.
1943
Fermi would have known of the Met Lab discussions.
His proposal to
Oppenheimer at the April conference was different from those essentially
defensive concerns, however, and clearly offensive in intent.
He may well
have been motivated in part by his scientific conservatism: may have asked
himself what recourse was open to the United States if a fast-fission bomb
proved impossible—it could not be demonstrated by experiment for at least
two years—and have found the answer in the formidable neutron flux of CP-
1 and its intended successors.
Oppenheimer swore Fermi to intimate secrecy
within the larger secrecy of the Manhattan Project; when the Italian laureate
returned to Chicago he went quietly to work.
In May Oppenheimer traveled to Washington.
Among other duties he
reported Fermi’s ideas to Groves and learned of the Conant subcommittee.
Back at Los Alamos on May 25 he wrote Fermi a warm letter reporting what
he had found.
He attributed the subcommittee assignment to a request from
the Army Chief of Staff, George Marshall, although it seems far likelier that
the study originated within the Manhattan Project.
“I therefore, with Groves’
knowledge and approval, discussed with [Conant] the application [i.e.,
poisoning German food supplies] which seemed to us so promising.
”1944
Oppenheimer had also discussed Fermi’s idea with Edward Teller.
e
isotope the men identified that “appears to offer the highest promise” was
strontium, probably strontium 90, which the human body takes up in place
of calcium and deposits dangerously and irretrievably in bone.
Teller
thought that separating the strontium from other pile products “is not a very
major problem.” Oppenheimer wanted to delay the work until “the latest safe
date,” he told Fermi further, so that they would have “a much better chance
of keeping your plan quiet.” He did not even want to include Compton in
any immediate discussion.
Summarizing, he wrote in part:
I should recommend delay if that is possible.
(In this connection I think
that we should not attempt a plan unless we can poison food sufficient to
kill a half a million men, since there is no doubt that the actual number
affected will, because of non-uniform distribution, be much smaller than
this.)
ere is no better evidence anywhere in the record of the increasing
bloody-mindedness of the Second World War than that Robert
Oppenheimer, a man who professed at various times in his life to be
dedicated to Ahimsa (“the Sanscrit word that means doing no harm or hurt,”
he explains) could write with enthusiasm of preparations for the mass
poisoning of as many as five hundred thousand human beings.
1945
Mid-1943 was in any case a season of great apprehension among the
atomic scientists, who saw Nazi Germany beginning to lose the war and
sensed that country’s desperation.
e Manhattan Project expected to
produce atomic bombs by early 1945; if Germany had begun fission research
in 1939 at similar scale it should have bombs nearly in hand.
Hans Bethe
and Edward Teller wrote Oppenheimer in a memorandum on August 21:
Recent reports both through the newspapers and through secret service,
have given indications that the Germans may be in possession of a
powerful new weapon which is expected to be ready between November
and January.1946 ere seems to be a considerable probability that this
new weapon is tubealloy [i.e., uranium].
It is not necessary to describe the
probable consequences which would result if this proves to be the case.
It is possible that the Germans will have, by the end of this year,
enough material accumulated to make a large number of gadgets which
they will release at the same time on England, Russia and this country.
In
this case there would be little hope for any counter-action.
However, it is
also possible that they will have a production, let us say, of two gadgets a
month.
is would place particularly Britain in an extremely serious
position but there would be hope for counter-action from our side before
the war is lost, provided our own tubealloy program is drastically
accelerated in the next few weeks.
e memorandum goes on to criticize the handling of production “entirely
by large companies”—the Hungarian threnody Szilard and Wigner also
sounded—and to propose a crash program directed by Urey and Fermi to
build heavy-water piles.
Nothing seems to have come of the Bethe-Teller
proposal—Hitler’s secret weapons proved to be the V-l and V-2 rockets then
in development at Peenemünde, the first of which crossed the English coast
on June 13, 1944—but it captures the mid-war mood.
Less worrisome was radioactive dusting.
Conant’s subcommittee
considered the possibilities and concluded that they were “rather
remote.” 1947 Conant emphasized that he thought it “extremely unlikely that a
radioactive weapon will be used against the U.S.
and unlikely the weapon
will be used at all.” Groves eventually proposed to George Marshall that a
handful of officers be trained in the use of Geiger counters and sent to
England to observe.
Preparing for the Normandy invasion, Marshall
approved.
* * *
It was easier for Americans guarded by the wide moat of the Atlantic than
for the British to dismiss the possibility of radioactive attack.
Sir John
Anderson, Chancellor of the Exchequer, a scientist and the member of
Churchill’s cabinet responsible for the Tube Alloys program, discussed the
question with Conant at lunch at the Cosmos Club in Washington in August
1943.
1948 He was concerned particularly about German heavy-water
production because British scientists believed they had found a way to
separate light from heavy water at five times the efficiency of existing
processes and feared their German counterparts might have made the same
discovery.
Heavy water would certainly work to moderate a chain-reacting
pile.
And such a machine might be used to breed radioactive isotopes for
dusting London.
e British therefore kept closer watch on the High Concentration Plant
at Vemork in Norway.
1949 It had not been damaged beyond repair.
To the
contrary, intelligence sources reported that summer, it had begun
production again in April; German scientists had shipped heavy water from
laboratory stocks in Germany to refill the various cells and speed restoration
of the cascade.
When Niels Bohr escaped from Stockholm to Scotland on October 6,
1943, he carried with him Werner Heisenberg’s drawing of an experimental
heavy-water reactor.
Bohr met more than once in London that autumn with
Sir John Anderson; Anderson matched up Bohr’s information with the
Conant subcommittee’s radioactive-warfare study and the Norwegian
underground’s news of Vemork’s renewed production and concluded that
the plant once again urgently required attack.
e Nazis had significantly
increased security at Vemork, which ruled out another commando raid.
Aer British and American representatives discussed the problem in
Washington George Marshall authorized precision bombing.
American Eighth Air Force B-17’s climbed northeast from British bases
before dawn on the morning of November 16.
To minimize Norwegian
casualties the aircra were scheduled to drop their bombs during the Norsk
Hydro lunch period, between 11:30 A.M.
and noon.
No German fighters
came up from the defensive airfields of western Norway to delay them and
they elected to circle over the North Sea to kill time before penetrating the
Scandinavian peninsula.
at alerted German flak, which took a limited toll
as the bombers crossed the coast.
One hundred forty got through to Vemork
and released more than seven hundred 500-pound bombs.
None hit the
aiming point but four destroyed the power station and two damaged the
electrolysis unit that supplied hydrogen to the High Concentration Plant,
effectively shutting it down.
Abraham Esau of the Reich Research Council decided then to rebuild in
Germany.
To expedite construction the council planned to dismantle the
Vemork plant and remove it to the Reich.
e Norwegian underground
reported that decision to London.
Anderson was less concerned with the
plant itself—Germany had only limited hydroelectricity to divert to its
operation—than with the heavy water preserved in its cascade.
British
intelligence asked the Norwegians to keep watch.
Word came by way of clandestine shortwave radio from the Rjukan area
on February 9, 1944, that the heavy water would be transported under guard
to Germany within a week or two—not enough warning to prepare and
drop in a squad of saboteurs.
Knut Haukelid, who had spent the past year
living on the land and organizing future military operations, was the only
trained commando in the area except for the radio operator.
He would have
to destroy the heavy water alone with whatever amateur help he could
assemble.
Haukelid slipped into Rjukan at night and met secretly with the new chief
engineer at Vemork, Alf Larsen.
Larsen agreed to help and they discussed
possible operations.
e heavy water, of enrichments varying from 97.6
down to 1.1 percent, would be transferred to some thirty-nine drums
labeled potash-lye.1950 “A one-man attack on Vemork,” writes Haukelid, “I
considered out of the question....
e only practical possibility, therefore,
was to try to carry out an attack on the transport in one way or another.” 1951
He and Larsen, joined later by the Vemork transport engineer, considered
the various stages of the journey.
e drums of water would go by train from
Rjukan to the head of Lake Tinnsjö.
From there the cars would be run onto a
rail ferry to travel the length of the lake, proceeding beyond Tinnsjö again
by train to the port where they would be loaded aboard a ship bound for
Germany.
Blowing up the trains would be difficult and bloody, since they
would be crowded with Norwegian passengers; Haukelid finally decided to
attempt to sink the ferry, which also carried passengers, into the 1,300-foot
lake.
e transport engineer agreed to arrange to dispatch the heavy water
on a Sunday morning, when the ferry was usually least crowded.
Sabotaging the boat would almost certainly mean the deaths of some of
the shipment’s German guards, which would call down heavy reprisals in the
Tinnsjö area against the Norwegian population.
Haukelid radioed London
for permission, emphasizing that his engineer compatriots had questioned if
the results were worth the reprisals:
e fact that the Germans were using heavy water for atomic
experiments, and that an atomic explosion might possibly be brought
about, was a thing we now talked of openly.
At Rjukan they doubted very
much whether the Germans had come in sight of a solution.
ey also
doubted whether an explosion of the kind could be brought about at
all.
1952
e British begged to differ:
e answer came from London the same day:1953
“Matter has been considered.
It is thought very important that the
heavy water shall be destroyed.
Hope it can be done without too
disastrous results.
Send our best wishes for success in the work.
Greetings.”
So Knut Haukelid laid his plans.
He put on workman’s clothes, packed his
Sten gun into a violin case, identified which ferry would make the run on
Sunday, February 20, 1944, the appointed day, and rode it with one eye on
his watch.
e Hydro was flat and bargelike with twin smokestacks jutting
up side by side through its boxy superstructure.
It reached the deepest part
of the lake about thirty minutes aer sailing and took twenty minutes then
to cross to shallower waters.
“We had therefore a margin of twenty minutes
in which the explosion must take place.
”1954 For even such generous leeway
Haukelid needed something better than a time fuse: he needed electric
detonators and a clock.
He visited a Rjukan hardware-store owner at night
for the detonators but was suspiciously turned away.
One of his local
compatriots had better luck.
A handyman retired from Norsk Hydro
donated one alarm clock to the cause; Alf Larsen supplied a backup.
Haukelid modified them so that their hammers struck not bells but contact
plates, closing a battery-powered electrical circuit that could fire the
detonators.
Months earlier the British had dropped supplies to the Norwegian
commando that included sticks of plastic explosive.
Haukelid strung the
stubby sticks together to make a circumferential loop to cut a hole in the
bottom of the ferry.
“As the Tinnsjö is narrow, the ferry must sink in less
than five minutes, or else it would be possible to beach her.
I...
spent many
hours sitting and calculating how large the hole must be for the ferry to sink
quickly enough.” 1955 To test his timing mechanism he hooked up a few spare
detonators at his cabin on the mountain above Rjukan aer a long night’s
work, set the alarm for evening and lay down to sleep.
e detonators went
off on schedule; he bolted bewildered from bed, grabbed the nearest gun and
reflexively covered the door.
“e timing apparatus seemed to be working
properly.
”1956
On Saturday Haukelid and a local compatriot, Rolf Sörlie, slipped into
Rjukan.
It was crowded with German soldiers and SS police.
An hour before
midnight “Rolf and I went over to the bridge which crossed the river Maan
and had a look at our target.” e freight cars “had been run up under some
lamps, and were guarded....
e train was to go at eight next morning, and
the ferry was due to leave...
at ten.” 1957
From the bridge the two men slipped to a back street where they met their
driver in a car Haukelid had arranged with its owner to steal in the name of
the King and return on Sunday morning.
e owner had modified the car to
run on methane and they were a long hour starting it.
ey picked up
Larsen, who was prepared to escape Norway to avoid arrest aer the work
was done.
He brought a suitcase of valuables and had come directly from a
dinner party where he had heard a visiting concert violinist mention plans
to leave on the morning ferry and had tried unsuccessfully to convince the
musician to stay in the area one more day to sample its excellent skiing.
Another Rjukan man also joined them.
ey drove to the lake well past the
middle of the night:
Armed with Sten guns, pistols and hand-grenades, we crept...
down
toward the ferry.
e bitterly cold night set everything creaking and
crackling; the ice on the road snapped sharply as we went over it.
When
we came out on the bridge by the ferry station, there was as much noise as
if a whole company was on the march.1958
Rolf and the other Rjukan man were told to cover me while I went on
board to reconnoitre.
All was quiet there.
Was it possible that the
Germans had omitted to place a guard at the weakest point in the whole
route to the transport?
Hearing voices in the crew’s quarters, forward, I stole to the
companion[way] and listened.
ere must be a party going on down
there, and a game of poker.
e other two followed me on to the deck of
the ferry.
We went down to the third-class accommodation and found a
hatchway leading to the bilges.
But before we had got the hatch open we
heard steps, and took cover behind the nearest table or chair.
e ferry
watchman was standing in the doorway.
Haukelid thought fast.
“e situation was awkward, but not dangerous.” He
told the watchman they were escaping the Gestapo and needed a place to
hide:
e watchman immediately showed us the hatchway in the deck, and told
us that they had several times had illicit things with them on their trips.
e Rjukan man now proved invaluable.
He talked and talked with the
watchman, while Rolf and I flung our sacks down under the deck and
began to work.
It was an anxious job, and it took time.
Haukelid and Sörlie found themselves standing on the bottom plates of
the boat in a foot of cold water.
ey had to tape the two alarm-clock timers
to one of the steel stringers that braced the ferry’s hull, attach four electric
detonators to the timers, attach high-speed fuses to the loop of plastic
explosive, lay the charge of explosive on the bottom plates and then, most
dangerously, hook up batteries to detonators and detonators to fuses.
“e charge was placed in the water and concealed.
It consisted of
nineteen pounds of high explosive laid in the form of a sausage.
We laid it
forward, so that the rudder and propeller would rise above the surface when
water began to come in [to prevent navigating the boat to shallower
water]....
When the charge exploded, it would blow about eleven square
feet out of the ship’s side.
”1959 e sausage was some twelve feet around.
Sörlie went up on deck.
Haukelid set his alarms to go off at 10:45 A.M.
“Making the last connection was a dangerous job; for an alarm clock is an
uncertain instrument, and contact between the hammer and the alarm was
avoided by not more than a third of an inch.
us there was one third of an
inch between us and disaster.
”1960 Everything worked and he finished at 4
A.M.
e Rjukan man had convinced the watchman by then that the escapees
he had sheltered needed to return to Rjukan to collect their possessions.
Haukelid considered warning their benefactor but decided that might
endanger the mission and only thanked him and shook his hand.
Ten minutes from the ferry station Haukelid and Larsen le the car to ski
to Kongsberg, forty miles away around the lake, where they would catch a
train for the first leg of their escape to Sweden.
Sörlie carried a report for
London to the clandestine radio.
e driver returned the stolen car and he
and the Rjukan man strolled home.
At Haukelid’s suggestion the Norsk
Hydro transport engineer had arranged a foolproof alibi: over the weekend
doctors at the local hospital operated on him for appendicitis, no questions
asked.
With fiy-three people aboard including the concert violinist the Hydro
sailed on time.
Forty-five minutes into the crossing Haukelid’s charge of
plastic explosive blew the hull.
e captain felt the explosion rather than
heard it, and though Tinnsjö is landlocked he thought they might have been
torpedoed.
e bow swamped first as Haukelid had intended; while the
passengers and crew struggled to release the lifeboats, the freight cars with
their thirty-nine drums of heavy water—162 gallons mixed with 800 gallons
of dross—broke loose, rolled overboard and sank like stones.
Of passengers
and crew twenty-six drowned.
e concert violinist slipped high and dry
into a lifeboat; when his violin case floated by, someone was kind enough to
fish it out for him.
Kurt Diebner of German Army Ordnance counted the full effect on
German fission research of the Vemork bombing and the sinking of the
Hydro in a postwar interview:
When one considers that right up to the end of the war, in 1945, there was
virtually no increase in our heavy-water stocks in Germany...
it will be
seen that it was the elimination of German heavy-water production in
Norway that was the main factor in our failure to achieve a self-sustaining
atomic reactor before the war ended.
1961
e race to the bomb, such as it was, ended for Germany on a mountain lake
in Norway on a cold Sunday morning in February 1944.
* * *
Despite Pearl Harbor and the subsequent Japanese sweep across a million
square miles of Southeast Asia and the western Pacific, the Pacific theater
commanded less attention in the United States in the earlier years of the war
than did the European.
Partly that neglect was a result of the deliberate
national policy that gave priority to Europe.
“Europe was Washington’s
darling,” Pacific Fleet Admiral William F.
Halsey would write in a memoir,
“the South Pacific was only a stepchild.” 1962 But Americans also found it
difficult at first to take seriously an Asian island people who were small in
stature and radically different in culture.
Reporting from the Solomon
Islands east of New Guinea late in 1942, Time-Life correspondent John
Hersey found the typical U.S.
marine “very uneasy about what he feels is
Washington’s ignorance of the Pacific.
Sure, he argues, Hitler has to be
beaten, but that doesn’t mean we have to go on thinking of the Japs as funny
little ring-tailed monkeys.” 1963 e U.S.
Ambassador to Japan at the time of
the Pearl Harbor attack, Boston-born Joseph C.
Grew, confronted a similar
skepticism when he returned from Japanese internment and battled it by
traveling the nation lecturing:
e other day a friend, an intelligent American, said to me: “Of course
there must be ups and downs in this war; we can’t expect victories every
day, but it’s merely a question of time before Hitler will go down to defeat
before the steadily growing power of the combined air and naval and
military forces of the [Allies]—and then, we’ll mop up the Japs.” Mark
well those words, please.
“And then we’ll mop up the Japs.
”1964
Grew thought such bravado ill-advised.
“e Japanese have known what
we thought of them,” he told his audiences—“that they were little fellows
physically, that they were imitative, that they were not really very important
in the world of men and nations.
”1965 To the contrary, said Grew, they were
“united,” “frugal,” “fanatical” and “totalitarian”:1966
At this very moment, the Japanese feel themselves, man for man, superior
to you and to me and to any of our peoples.
ey admire our technology,
they may have a lurking dread of our ultimate superiority of resources,
but all too many of them have contempt for us as human beings....
e
Japanese leaders do think that they can and will win.
ey are counting on
our underestimates, on our apparent disunity before—and even during—
war, on our unwillingness to sacrifice, to endure, and to fight.1967
So far Grew’s lecture might have been merely exhortation.
But he went on
to emphasize a phenomenon that Americans fighting in the Pacific were just
then beginning to encounter.
“’Victory or death’ is no mere slogan for these
soldiers,” Grew noted.
“It is plain, matter-of-fact description of the military
policy that controls their forces, from the highest generals to the newest
recruits.
e man who allows himself to be captured has disgraced himself
and his country.” 1968
Which was exactly what Marine Major General Alexander A.
Vandegri
was finding at the time, late 1942, in the Solomons at Guadalcanal.
“General,” he wrote the Marine Commandant in Washington, “I have never
heard or read of this kind of fighting.
ese people refuse to surrender.
e
wounded will wait until men come up to examine them...
and blow
themselves and the other fellow to death with a hand grenade.” 1969
It was frightening.
It required a corresponding escalation of violence to
combat.
John Hersey felt the need to explain:
A legend has grown up that this young man [i.e., the U.S.
marine] is a
killer; he takes no prisoners, and gives no quarter.
is is partly true, but
the reason is not brutality, not just vindictive remembrance of Pearl
Harbor.
He kills because in the jungle he must, or be killed.
is enemy
stalks him, and he stalks the enemy as if each were a hunter tracking a
bear cat.
Quite frequently you hear marines say: “I wish we were fighting
against Germans.
ey are human beings, like us.
Fighting against them
must be like an athletic performance—matching your skill against
someone you know is good.
Germans are misled, but at least they react
like men.
But the Japs are like animals.
Against them you have to learn a
whole new set of physical reactions.
You have to get used to their animal
stubbornness and tenacity.
ey take to the jungle as if they had been
bred there, and like some beasts you never see them until they are
dead.
”1970
As an explanation for unfamiliar behavior, bestiality had the advantage
that it made killing a formidable enemy easier emotionally.
But it also, by
dehumanizing him, made him seem yet more alien and dangerous.
So did
the other common attribution that evolved during the war to explain
Japanese behavior: that the Japanese were fanatics, believers, as Grew had
preached, “in the incorruptible certainty of their national cause.” 1971 e
historian William Manchester, a marine at Guadalcanal, argues more
objectively from a longer perspective postwar:
At the time it was impolitic to pay the slightest tribute to the enemy, and
Nip determination, their refusal to say die, was commonly attributed to
“fanaticism.” In retrospect it is indistinguishable from heroism.
To call it
anything less cheapens the victory, for American valor was necessary to
defeat it.1972
Whether bestiality, fanaticism, or heroism, the refusal of Japanese soldiers
to surrender required new tactics and strong stomachs to defeat.
In his best-
selling 1943 book Guadalcanal Diary war correspondent Richard Tregaskis
reported those tactics from the first land battles of the Pacific war at
Guadalcanal:
e general summarized the fighting....
e toughest job, he said, had
been to clean out scores of dugout caves filled with Japs.
Each cave, he
said, had been a fortress in itself, filled with Japs who were determined to
resist until they were all killed.
e only effective way to finish off these
caves, he said, had been to take a charge of dynamite and thrust it down
the narrow cave entrance.
Aer that had been done, and the cave blasted,
you could go in with a submachine gun and finish off the remaining
Japs....
“You’ve never seen such caves and dungeons,” said the general.
“ere
would be thirty or forty Japs in them.
And they absolutely refused to
come out, except in one or two isolated cases.” 1973
e statistics of the Solomons campaign told the same story: of 250 Japanese
manning the garrison on Guadalcanal when the marines first landed only
three allowed themselves to be taken prisoner; more than 30,000 Japanese
shipped in to fight died before the island was secure, compared to 4, 123
Americans.
Similar patterns obtained elsewhere.
e proportion of captured
to dead Japanese in the North Burma campaign was 142 to 17, 166, about
1:120 when a truism among Western nations is that the loss of one-fourth to
one-third of an army—4:1—usually bodes surrender.
Paralleling Japanese
resistance, Allied losses grew.
As the slow, bloody push up the Pacific toward the Japanese home islands
gained momentum through 1943, the question the behavior of Japanese
soldiers raised was whether such standards applied not only to the military
but to the civilians of Japan as well.
Grew had sought to answer that question
in his lectures the year before:
I know Japan; I lived there for ten years.
I know the Japanese intimately.
e Japanese will not crack.
ey will not crack morally or
psychologically or economically, even when eventual defeat stares them in
the face.
ey will pull in their belts another notch, reduce their rations
from a bowl to a half bowl of rice, and fight to the bitter end.
Only by
utter physical destruction or utter exhaustion of their men and materials
can they be defeated.
at is the difference between the Germans and the
Japanese.
at is what we are up against in fighting Japan.1974
In the meantime the United States manufactured flamethrowers to burn
Japanese soldiers from their caves.
A seasoned journalist who had traveled
in Japan before the war, Henry C.
Wolfe, called in Harper’s for the
firebombing of Japan’s “inflammable,” “matchbox” cities.
“It seems brutal to
be talking about burning homes,” Wolfe explained.
“But we are engaged in a
life-and-death struggle for national survival, and we are therefore justified in
taking any action that will save the lives of American soldiers and sailors.
We must strike hard with everything we have at the spot where it will do the
most damage to the enemy.
”1975
e month Wolfe’s call to aerial battle appeared in Harper’s—January 1943
—Franklin Roosevelt met with Winston Churchill at Casablanca.
In the
course of the meeting the two leaders discussed what terms of surrender
they would eventually insist upon; the word “unconditional” was discussed
but not included in the official joint statement to be read at the final press
conference.
en, on January 24, to Churchill’s surprise, Roosevelt inserted
the word ad lib: “Peace can come to the world,” the President read out to the
assembled journalists and newsreel cameras, “only by the total elimination
of German and Japanese war power....
e elimination of German,
Japanese and Italian war power means the unconditional surrender of
Germany, Italy, and Japan.
”1976 Roosevelt later told Harry Hopkins that the surprising and fateful insertion was a consequence of the confusion
attending his effort to convince French General Henri Girard to sit down
with Free French leader Charles de Gaulle:
We had so much trouble getting those two French generals together that I
thought to myself that this was as difficult as arranging the meeting of
Grant and Lee—and then suddenly the Press Conference was on, and
Winston and I had had no time to prepare for it, and the thought popped
into my mind that they had called Grant “Old Unconditional Surrender,”
and the next thing I knew I had said it.
1977
Churchill immediately concurred—“Any divergence between us, even by
omission, would on such an occasion and at such a time have been
damaging or even dangerous to our war effort”—and unconditional
surrender became official Allied policy.
16
Revelations
“How would you like to work in America?” James Chadwick asked Otto
Frisch in Liverpool one day in November 1943.
1978
“I would like that very much,” Frisch remembers responding.
“But then you would have to become a British citizen.”
“I would like that even more.”
Within a week the British had cleared the Austrian emigré for citizenship.
Following instructions “to pack all my necessary belongings into one
suitcase and to come to London by the night train” Frisch made the rounds
of government offices with other emigré scientists in one crowded day—
swearing allegiance to the King, picking up a passport, collecting a visa
stamp at the American Embassy—and hurried back to Liverpool, where the
delegation would board the converted luxury liner Andes the next morning.
Headed by Wallace Akers of ICI, the British group included the men
General Groves would ask to review barrier development as well as men
going to Los Alamos: Frisch, Rudolf Peierls, William G.
Penney, George
Placzek, P.
B.
Moon, James L.
Tuck, Egon Bretscher and Klaus Fuchs among
others.
Chadwick would join them, as would the hydrodynamicist Geoffrey
Taylor.
Akers maneuvered around the transport shortage by loading them for the
Liverpool pier in black mortuary limousines; a hearse for the luggage
completed the cortege.1979 On the Andes Frisch had an entire eight-berth cabin to himself.
Unconvoyed they zigzagged west.
America was luxury;
traveling up from Newport News Frisch’s train stopped in Richmond,
Virginia:
I wandered out into the streets.
ere I was greeted by a completely
incredible spectacle: fruit stalls with pyramids of oranges, illuminated by
bright acetylene flares!
Aer England’s blackout, and not having seen an
orange for a couple of years, that sight was enough to send me into
hysterical laughter.1980
Groves in Washington lectured them on security.
A succession of trains
delivered them into a fantastic landscape—Frisch and another man in
December, the larger group early in 1944—and there in the bright sunlight
of a pine-shouldered mesa was Robert Oppenheimer smoking a pipe and
shading his close-cropped military haircut with a pork-pie hat: “Welcome to
Los Alamos, and who the devil are you?” 1981, 1982, 1983
ey were Churchill’s flying wedge.
e bomb had been theirs to begin
with as much as anybody’s, but more immediate urgencies had demanded
their attention and now they were couriers sent along to help build it and
then to bring it home.
America was giving the bomb away to another
sovereign state, proliferating.
Churchill had negotiated the renewed
collaboration at Quebec in August:
It is agreed between us
First, that we will never use this agency against each other.
Secondly, that we will not use it against third parties without each
other’s consent.
irdly, that we will not either of us communicate any information
about Tube Alloys to third parties except by mutual consent.
Niels Bohr and his son Aage followed next as consultant to the Tube
Alloys directorate and junior scientific officer, respectively; the British were
paying their salaries.
Groves’ security men met father and son at dockside,
assigned them cover names—Nicholas and James Baker—and spirited them
off to a hotel, there to discover NIELS BOHR stenciled bold and black on the
Danish laureate’s luggage.
At Los Alamos, warmly welcomed, Nicholas and
James Baker became Uncle Nick and Jim.
e first order of business was Heisenberg’s drawing of a heavy-water
reactor, which Bohr had previously revealed to Groves.
Oppenheimer
convened a conference of experts on the last day of 1943 to see if they could
find any new reason to believe a pile might serve as a weapon.
“It was clearly
a drawing of a reactor,” Bethe recalled aer the war, “but when we saw it our
conclusion was that these Germans were totally crazy—did they want to
throw a reactor down on London?” at was not Heisenberg’s purpose, but
Bohr wanted to be sure.
Bethe and Teller prepared the consequent report,
“Explosion of an inhomogeneous uranium-heavy water pile.
”1984, 1985 It
found that such an explosion “will liberate energies which are probably
smaller, and certainly not much larger, than those obtainable by the
explosion of an equal mass of TNT.”
If Heisenberg’s drawing told the physicists anything it ought to have told
them that the Germans were far behind; it depicted sheets of uranium rather
than lumps, an inefficient arrangement Heisenberg had clung to for a time
even when his colleagues had argued the advantages of a threedimensional
lattice.
Samuel Goudsmit, a Dutch physicist in America who would soon
lead a front-line Manhattan Project intelligence mission into Germany,
remembers a more convoluted conclusion: “At that time we thought this
meant simply that they had succeeded in keeping their real aims secret, even
from a scientist as wise as Bohr.
”1986
Oppenheimer appreciated the salutary effect of Bohr’s presence.
“Bohr at
Los Alamos was marvelous,” he told an audience of scientists aer the war.
“He took a very lively technical interest....
But his real function, I think for
almost all of us, was not the technical one.
”1987 Here two texts of the postwar
lecture diverge; both versions illuminate Oppenheimer’s state of mind in
1944 as he remembered it.
In unedited transcript he said Bohr “made the
enterprise which looked so macabre seem hopeful”; edited, that sentence
became: “He made the enterprise seem hopeful, when many were not free of
misgiving.” 1988, 1989
How Bohr did so Oppenheimer and even Bohr had work to explain.
Oppenheimer outlines an explanation in his lecture:
Bohr spoke with contempt of Hitler, who with a few hundred tanks and
planes had tried to enslave Europe for a millennium.
He said nothing like
that would ever happen again; and his own high hope that the outcome
would be good, and that in this the role of objectivity, the cooperation
which he had experienced among scientists would play a helpful part; all
this, all of us wanted very much to believe.
1990
“He said nothing like that would ever happen again” is a key; Austrian
emigré theoretician Victor Weisskopf supplies another:
In Los Alamos we were working on something which is perhaps the most
questionable, the most problematic thing a scientist can be faced with.
At
that time physics, our beloved science, was pushed into the most cruel
part of reality and we had to live it through.
We were, most of us at least,
young and somewhat inexperienced in human affairs, I would say.
But
suddenly in the midst of it, Bohr appeared in Los Alamos.
1991
It was the first time we became aware of the sense in all these terrible
things, because Bohr right away participated not only in the work, but in
our discussions.
Every great and deep difficulty bears in itself its own
solution....
is we learned from him.
“ey didn’t need my help in making the atom bomb,” Bohr later told a
friend.
1992 He was there to another purpose.
He had le his wife and
children and work and traveled in loneliness to America for the same reason
he had hurried to Stockholm in a dark time to see the King: to bear witness,
to clarify, to win change, finally to rescue.
His revelation—which was
equivalent, as Oppenheimer said, to his revelation when he learned of
Rutherford’s discovery of the nucleus—was a vision of the complementarity
of the bomb.
In London and at Los Alamos Bohr was working out its
revolutionary consequences.
He meant now to communicate his revelation
to the heads of state who might act on it: to Franklin Roosevelt and Winston
Churchill first of all.
In December, before he first went out to Los Alamos, at a small reception
at the Danish Embassy in Washington where he and Aage lived when they
visited that city, Bohr had renewed his acquaintance with Supreme Court
Associate Justice Felix Frankfurter.
e justice was short, crackling, bright,
Vienna-born, an agnostic Zionist Jew, an ardent patriot, a close friend of
Franklin Roosevelt and one of the President’s longtime advisers.
Bohr had
met him in England in 1933 in connection with the rescue of the emigré
academics; when Bohr visited Washington in 1939, the year Frankfurter was
elevated to the Court, the two men developed what Frankfurter calls a
“warm friendly relation.
”1993 e December tea offered no opportunity to
talk privately, but on his way out Frankfurter proposed to invite Bohr to
lunch in chambers at the Supreme Court.
He already understood that
something was up.
e justice was three years older than the physicist, born in 1882, the
same year as Roosevelt.
He had emigrated to the United States with his
family in 1894, grown up on New York’s Lower East Side, graduated at
nineteen from the City College of New York and made a brilliant showing at
Harvard Law.
He worked for Henry Stimson when Stimson was U.S.
Attorney for the Southern District of New York, before the Great War, and
in Washington when Stimson served as Secretary of War the first time,
under William Howard Ta.
Harvard invited Frankfurter to a professorship
at its law school in 1914.
He held that post until Roosevelt appointed him to
the Supreme Court, but he was intensely active politically across those
academic years, a one-man recruiting agency for the New Deal, a loyal
friend who supported Roosevelt’s ill-advised 1937 scheme to pack the Court
to overwhelm its conservative resistance to his innovative legislation.
Aer Bohr returned to Washington from Los Alamos, in mid-February,
the two men kept their appointment for lunch.
Both le wartime
memoranda describing the meeting.
“We talked about the recent events in
Denmark,” Frankfurter writes, “the probable course of the war, the state of
England...
our certainty of German defeat and what lay ahead.
Professor
Bohr never remotely hinted the purpose of his visit to this country.” 1994
Fortunately Frankfurter had heard about the project he called X.
He says
he heard from “some distinguished American scientists,” but he certainly
heard from a distraught young Met Lab scientist who had penetrated all the
way to Frankfurter and Eleanor Roosevelt in 1943 with complaints about Du
Pont.
“I had thus become aware of X—aware, that is, that there was such a
thing as X and of its significance.” Since Frankfurter knew Bohr’s field he
assumed X was the reason for Bohr’s visit:
And so...
I made a very oblique reference to X so that if I was right in my
assumption that Professor Bohr was sharing in it, he would know that I
knew something about it....
He likewise replied in an innocent remote
way, but it soon became clear to both of us that two such persons, who
had been so long and so deeply preoccupied with the menace of Hitlerism
and who were so deeply engaged in the common cause, could talk about
the implications of X without either of us making any disclosure to the
other.
Eminent jurist and eminent physicist thus easily dispatched that modest
obstacle.
“Professor Bohr then expressed to me,” Frankfurter goes on, “his
conviction that X might be one of the greatest boons to mankind or might
become the greatest disaster...
and he made it clear to me that there was
not a soul in this country with whom he could or did talk about these things
except Lord Halifax [the British ambassador] and Sir Ronald Campbell [a
British representative on the Anglo-American Combined Policy
Committee].” Bohr picks up the narrative in third-person voice: “On hearing
this F said that, knowing President Roosevelt, he was confident that the
President would be very responsive to such ideas as B outlined.
”1995
Bohr had found his go-between.
“B met F again one of the last days of
March,” Bohr records in his wartime memorandum, “and learned that in the
meantime F had had occasion to speak with the President and that the
President shared the hope that the project might bring about a turning point
in history.” 1996 Frankfurter describes his meeting with Roosevelt:
On this particular occasion I was with the President for about an hour
and a half and practically all of it was consumed by this subject.
He told
me the whole thing “worried him to death” (I remember the phrase
vividly), and he was very eager for all of the help he could have in dealing
with the problem.1997 He said he would like to see Professor Bohr and
asked me whether I would arrange it.
When I suggested to him that the
solution of this problem might be more important than all the schemes
for a world organization, he agreed and authorized me to tell Professor
Bohr that he, Bohr, might tell our friends in London that the President
was most eager to explore the proper safeguards in relation to X.
Much controversy surrounds this meeting, because Roosevelt later
implicitly repudiated it.
Why, if the President was worried to death about the
postwar implications of the bomb, did he entrust a mission to the British to
so informal an arrangement?
He had not even met Niels Bohr.
An answer to
this question would answer a more substantive question: whether Roosevelt
was in fact interested in exploring ideas of international control or whether
he was already committed to perpetuating an Anglo-American monopoly
(the Quebec Agreement implied commitment, and he had recently
discussed cornering the world uranium and thorium markets with Groves
and Bush).
Why did Roosevelt entrust so important a mission to Bohr?
In fact, the
commission worked the other way around: Bohr had come to the United
States representing the British, representing at least Sir John Anderson, who
had encouraged his visit as much to promote discussing the issues Bohr had
raised as to bolster the British Los Alamos mission.
If the commission was
informal it was no more so than any number of other backchannel
arrangements between the British and the Americans.
Roosevelt simply
responded to what he took to be a British approach.
He seems to have
assumed—correctly—that British statesmen around Churchill were using
Bohr to communicate to the President ideas about wartime and postwar
arrangements to which Churchill was not yet committed.
He responded
candidly with loyalty to his British counterpart, Bohr adds: “F also informed
B that as soon as the question had been brought up, the President had said it
was a matter for Prime Minister Churchill and himself to find the best ways
of handling the project to the benefit of all mankind, and that he should
heartily welcome any suggestion to this purpose from the Prime
Minister.” 1998 e President would be happy to discuss new ideas for
postwar relations, but the British would first have to convince the P.M.;
Roosevelt would not deal behind Churchill’s back.
Frankfurter implies this
understanding: “I wrote out such a formula for Bohr to take to London—a
communication to Sir John Anderson, who was apparently Bohr’s
connecting link with the British government.
”1999
Complicating Bohr’s discussions, in March and later, was the question of
what to do about the USSR.
Bohr considered the question in the following
perspective.
Tell the Soviet Union soon, before the first bombs were nearly
built, that a bomb project was under way, and the confidence might lead to
negotiations on postwar arms control.
Let the Soviet Union discover the
information on its own, build the bombs and drop them, oppose the Soviets
at the end of the war with an Anglo-American nuclear monopoly, and the
likeliest outcome was a nuclear arms race.
Bohr’s revelation of the complementarity of the bomb was far more
fundamental than this contemporary political question.
But the
contemporary political question was an aspect of the larger issue and partly
obscured it from view.
e bomb was opportunity and threat and would
always be opportunity and threat—that was the peculiar, paradoxical
hopefulness.
But political conditions would necessarily differ before and
aer it was deployed.
At the end of March 1944, Bohr seemingly had a mandate from the
President of the United States to talk to the Prime Minister of Great Britain.
e British in whom Bohr had been confiding were properly impressed.
“Halifax considered this development to be so important,” writes Aage Bohr,
“that he thought my father should go to London immediately.
”2000 Father
and son crossed the Atlantic again, this time by military aircra, in early
April.
Anderson had been working to soen Churchill up.
e tall, dark
Chancellor of the Exchequer, whom Oppenheimer describes as a
“conservative, dour, remarkably sweet man,” sent the Prime Minister a long
memorandum on March 21.2001 He suggested opening Tube Alloys to wider
discussion within the British government.
Echoing Bohr, he saw the
possibility of international proliferation of nuclear weapons aer the war.
He
thought the only alternative to a vicious arms race was international
agreement.
He proposed “communicating to the Russians in the near future
the bare fact that we expected, by a given date, to have this devastating
weapon; and...
inviting them to collaborate with us in preparing a scheme
for international control.” 2002, 2003
Churchill circled “collaborate” and wrote in the margin: “on no account.”
When Bohr arrived Anderson wrote the Prime Minister again, going over
the same arguments but adding that he now believed Roosevelt was
attending the subject and would welcome discussion.
He even supplied a
dra message Churchill might send to initiate an exchange.
e response
was equally waspish: “I do not think any such telegram is necessary nor do I
wish to widen the circle who are informed.
”2004
Churchill was in no mood to see Bohr; the Danish laureate cooled his
heels for weeks.
While he waited he heard from the Soviets.
Peter Kapitza
had written Bohr shortly aer the Bohrs escaped from Denmark—the letter
found its way from Stockholm to the Soviet Embassy in London—“to let you
know that you will be welcome to the Soviet Union where everything will be
done to give you and your family a shelter and where we now have all the
necessary conditions for carrying on scientific work.
”2005 Aer alerting the
Tube Alloys security officer Bohr went to the embassy in Kensington
Gardens to collect the letter; on his return he reported his conversation with
the embassy’s counsellor.
Amid much talk about the greatness of Russian
science and how few friends Russia had counted before the war was the
heart of the matter:
e Counsellor then said that he knew that B had recently been to
America, and B said that he had received from the journey many
encouraging expressions of the wish for international cultural co-
operation and that he hoped soon to come to Russia also.
e Counsellor
next asked what information B had received about the work of American
scientists during the war, and B answered that the American scientists,
just like the Russian and the British, had surely made very large
contributions to the war effort which would no doubt be of great
importance for an appreciation of science everywhere aer the war.
B
thereaer told a little about the situation in Denmark during the
occupation.
2006
Quickly changing the subject.
But for Bohr the blunt question and Kapitza’s
invitation to come to Moscow were enough to indicate that the Soviets had
at least an inkling of the bomb project and might be working on their own.
Which meant there was very little time le to convince them that a secret
arms race had not already begun.
He carried that urgency with him when he
was called with Cherwell, finally, on May 16, to 10 Downing Street.
“We came to London full of hopes and expectations,” Aage Bohr
remembers.
“It was, of course, a rather novel situation that a scientist should
thus try to intervene in world politics, but it was hoped that Churchill, who
possessed such imagination and who had oen shown such great vision,
would be inspired by the new prospects.
”2007 Niels Bohr cherished that hope.
His British friends had not prepared him.
“One of the blackest comedies of the war,” C.
P.
Snow characterizes the
disastrous confrontation.2008 e definitive account is from R.
V.
Jones,
Cherwell’s protégé, who had helped make arrangements and who was
surprised to find Bohr wandering a few hours later in Old Queen Street
outside the Tube Alloys office:2009
When I asked him how the meeting had gone he said: “It was terrible.
He
scolded us like two schoolboys!” From what he told me at that time and
aerwards, it appeared that the meeting misfired from the start.
2010
Churchill was in a bad mood, and he berated Cherwell for not having
arranged the interview in a more regular manner.
He then said he knew
why Cherwell had done it—it was to reproach him about the Quebec
Agreement.
is, of course, was quite untrue, but it meant that Bohr’s “set
piece” talk was thrown right out of gear.
Bohr, who used to say that
accuracy and clarity were complementary (and so a short statement could
never be precise), was not easy to hear, and all that Churchill seemed to
gather was that he was worried about the likely state of the post-war world
and that he wanted to tell the Russians about the progress towards the
bomb.
As regards the post-war world Churchill told him: “I cannot see
what you are talking about.
Aer all this new bomb is just going to be
bigger than our present bombs.
It involves no difference in the principles
of war.
And as for any post-war problems there are none that cannot be
amicably settled between me and my friend, President Roosevelt.”
Bohr got only the bare thirty minutes of his scheduled appointment, most of
which Churchill had monopolized.
“As he was leaving,” Aage Bohr
concludes, “my father asked for permission to write Churchill, whereupon
the latter answered, ‘It will be an honour for me to receive a letter from you,’
adding, ‘but not about politics!’”2011
“We did not speak the same language,” Bohr said aerward.
2012 His son
found him “somewhat downcast.” 2013 He was angrier than that; in his
seventy-second year, still stinging, he told an old friend: “It was terrible that
no one over there”—England and America both—“had worked on the
solution of the problems that would arise when it became possible to release
nuclear energy; they were completely unprepared.
”2014 And further, “It was
perfectly absurd to believe that the Russians cannot do what others can....
ere never was any secret about nuclear energy.”
Churchill’s obduracy was compound but straightforward.
He was up to his
neck in preparations for the Normandy invasion; he sniffed conspirators
encroaching back-channel and instinctively swatted them down; he resented
the awe his colleagues accorded this certified great man (“I did not like the
man when you showed him to me, with his hair all over his head, at
Downing Street,” he gnawed at Cherwell aerward); he could not listen
carefully enough, or was too certain of his own opinions, to be convinced
that the bomb would change the rules.2015 A year later the seventyyear-old
Prime Minister had budged no further.
“In all the circumstances,” he wrote
Anthony Eden in 1945, “our policy should be to keep the matter so far as we
can control it in American and British hands and leave the French and
Russians to do what they can.
You can be quite sure that any power that gets
hold of the secret will try to make the article and this touches the existence
of human society.
is matter is out of all relation to anything else that exists
in the world, and I could not think of participating in any disclosure to third
or fourth parties at the present time.” 2016
“He had always had a naive faith in ‘secrets,’ ” concludes C.
P.
Snow.
“He
had been told by the best authorities that this ‘secret’ wasn’t keepable and
that the Soviets would soon have the bomb themselves.
Perhaps, with one of
his surges of romantic optimism, he deluded himself into not believing it.
He was only too conscious that British power, and his own, was now just a
vestige.
So long as the Americans and British had the bomb in sole
possession, he could feel that that power hadn’t altogether slipped away.
It is
a sad story.” 2017
Bohr wrote Churchill on May 22; the letter was circumspect but political
aer all and conveyed what he had not been allowed to convey at the
meeting: “that the President is deeply concerned in his own mind with the
stupendous consequences of the project, in which he sees grave dangers, but
also unique opportunities.” Bohr did not spell out these opportunities.
He
even seemed to step back from offering advice: “e responsibility for
handling the situation rests, of course, with the statesmen alone.
e
scientists who are brought into confidence can only offer the statesmen all
such information about technical matters as may be of importance for their
decisions.
”2018 ose technical matters, however, Bohr made sure to note,
included the probability of proliferation and of bigger bombs—he had
learned of the Super at Los Alamos.
Apparently Churchill did not trouble himself to respond.
Bohr stayed on in London for several more weeks.
He was thus on hand
for D-Day, Tuesday, June 6, 1944.
“e greatest amphibious assault ever
attempted,” Dwight D.
Eisenhower, the Supreme Allied Commander, called
that invasion of Europe across the English Channel with an initial force of
156,000 British, Canadian and American soldiers supported by 1,200
warships, 1,500 tanks and 12,000 aircra.
By the time Bohr and his son le
England at the end of the week to return to the United States the Allies had
secured the invasion beaches and begun advancing inland with a force
bolstered now to 326,000 men.
“e way home,” Eisenhower instructed his
armies, “is via Berlin.” 2019
For Bohr the way home was via Washington.
He reported his dismal
experience with Churchill to Felix Frankfurter on June 18.
Frankfurter
immediately carried the news to Roosevelt, who was amused to hear another
tale of Churchillian pugnacity:
About a week later F told B that this information had been heartily
welcomed by the President who had said that he regarded the steps taken
as a favourable development.
During the talk the President had expressed
the wish to see B, and as a preliminary step F advised B to give an account
of his views in a brief memorandum.
2020
e Bohrs turned to the task as Washington steamed, the last days of June
and the first days of July dawning in the high eighties and sweltering above
100° by aernoon.
Aage Bohr recalls the document’s preparation:
It was worked out in the tropical heat of Washington and, like all my
father’s work, underwent many stages before it was ready for delivery.
In
the morning, my father would usually bring up new ideas for alterations
that he had thought out during the night.
ere was no secretary to whom
we could entrust such documents, and therefore I typed them; meanwhile
my father darned socks and sewed buttons on for us, a job which he
carried out with his usual thoroughness and manual skill.2021
Sewing on buttons, darning socks, suffering in the heat that seemed
equatorial to a Dane of the cold North Sea, Bohr worked and reworked his
memorandum to maximum generality of expression, a political analysis as
reserved as any scientific paper.2022 It says all that he had seen up to that
time, which was almost everything essential.
Late in life Bohr explained the starting point of his revelation in a single
phrase.
“We are in a completely new situation that cannot be resolved by war,”
he confided to a friend.
2023 He had already grasped that fundamental point
when he arrived at Los Alamos in 1943 and told Oppenheimer that nothing
like Hitler’s attempt to enslave Europe would ever happen again.
“First of
all,” Oppenheimer confirms, “[Bohr] was clear that if it worked, this
development was going to bring an enormous change in the situation of the
world, in the whole situation of war and the tolerability of war.” 2024
e weapon devised as an instrument of major war would end major war.
It was hardly a weapon at all, the memorandum Bohr was writing in
sweltering Washington emphasized; it was “a far deeper interference with
the natural course of events than anything ever before attempted” and it
would “completely change all future conditions of warfare.
”2025 When
nuclear weapons spread to other countries, as they certainly would, no one
would be able any longer to win.
A spasm of mutual destruction would be
possible.
But not war.
at was new ground, ground the nations had never walked before.
It was
new as Rutherford’s nucleus had been new and unexplored.
Bohr had
searched the forbidding territory of the atom when he was young and
discovered multiple structures of paradox; now he searched it again by the
dark light of the energy it released and discovered profound political change.
Nations existed in a condition of international anarchy.
No hierarchical
authority defined their relations with one another.
ey negotiated
voluntarily as self-interest moved them and took what they could get.
War
had been their final negotiation, brutally resolving their worst disputes.
Now an ultimate power had appeared.
If Churchill failed to recognize it he
did so because it was not a battle cry or a treaty or a committee of men.
It
was more like a god descending to the stage in a gilded car.
It was a
mechanism that nations could build and multiply that harnessed unlimited
energy, a mechanism that many nations would build in self-defense as soon
as they learned of its existence and acquired the technical means.
It would
seem to confer security upon its builders, but because there would be no
sure protection against so powerful and portable a mechanism, in the course
of time each additional unit added to the stockpiles would decrease security
by adding to the general threat until insecurity finally revealed itself to be
total at every hand.
By the necessity, commonly understood, to avoid triggering a nuclear
holocaust, the deus ex machina would have accomplished then what men
and nations had been unable to accomplish by negotiation or by conquest:
the abolition of major war.
Total security would be indistinguishable from
total insecurity.
A menacing standoff would be maintained suspiciously,
precariously, at the brink of annihilation.
Before the bomb, international
relations had swung between war and peace.
Aer the bomb, major war
among nuclear powers would be self-defeating.
No one could win.
World
war thus revealed itself to be historical, not universal, a manifestation of
destructive technologies of limited scale.
Its time would soon be past.
e
pendulum now would swing wider: between peace and national suicide;
between peace and total death.
Bohr saw that far ahead—all the way to the present, when menacing
standoff has been achieved and maintained for decades without formal
agreement but at the price of smaller client wars and holocaustal nightmare
and a good share of the wealth of nations—and stepped back.
He wondered
if such apocalyptic precariousness was necessary.
He wondered if the war-
weary statesmen of the day, taught the consequences of his revelation, could
be induced to forestall those consequences, to adjourn the game when the
stalemate revealed itself rather than illogically to play out the menacing later
moves.
It was clear at least that the new weapons would be appallingly
dangerous.
If the statesmen could be brought to understand that the danger
of such weapons would be common and mutual, might they not negotiate
commonly and mutually to ban them?
If the end would be a warless world
either way, but one way with the holocaustal machinery in place and the
other way with its threat only considered and understood, what did they
have to lose?
Negotiating peace rather than allowing the deus ex machina
inhumanly to impose standoff might show the common threat to contain
within itself, complementarily, common promise.
Much good might follow.
“It appeared to me,” Bohr wrote in 1950 of his lonely wartime initiative, “that
the very necessity of a concerted effort to forestall such ominous threats to
civilization would offer quite unique opportunities to bridge international
divergencies.” 2026 at, in a single sentence, was the revelation of the complementarity of the bomb.
“Much thought has naturally been given to the question of [arms]
control,” Bohr flattered Franklin Roosevelt in his 1944 document, knowing
that hardly any thought had yet been given, “but the further the exploration
of the scientific problems concerned is proceeding” —to thermonuclear
weapons, Bohr means— “the clearer it becomes that no kind of customary
measures will suffice for this purpose and that especially the terrifying
prospect of a future competition between nations about a weapon of such
formidable character can only be avoided through a universal agreement in
true confidence.” 2027
Bohr was no fool.
Obviously no nation could be expected to trust another
nation’s bare word about something so vital to survival.
Each would want to
see for itself that the other was not secretly building bombs.
at meant the
world would have to open up.
He knew very well how suspicious the Soviet
Union would be of such an idea; he hoped, however, that the dangers of a
nuclear arms race might appear serious enough to make evident the
compensating advantages:
e prevention of a competition prepared in secrecy will therefore
demand such concessions regarding exchange of information and
openness about industrial efforts including military preparations as would
hardly be conceivable unless at the same time all partners were assured of
a compensating guarantee of common security against dangers of
unprecedented acuteness.2028
Nor was the urge to suspicious secrecy unique to the Soviets; the Americans
and the British were even then risking an arms race by keeping their work
on the atomic bomb secret from their Soviet allies.
Oppenheimer elaborates:
[Bohr] was clear that one could not have an effective control of...
atomic
energy...
without a very open world; and he made this quite absolute.
He
thought that one would have to have privacy, for he needed privacy, as we
all do; we have to make mistakes and be charged with them only from
time to time.
One would have to have respect for individual quiet, and for
the quiet process of government and management; but in principle
everything that might be a threat to the security of the world would have
to be open to the world.2029
Openness would accomplish more than forestalling an arms race.
As it did
in science, it would reveal error and expose abuse.
Men performed in
secrecy, behind closed doors and guarded borders and silenced printing
presses, what they were ashamed or afraid to reveal to the world.
Bohr
talked to George Marshall aer the war, when the Chief of Staff had
advanced to Secretary of State.
“What it would mean,” he told him, “if the
whole picture of social conditions in every country were open for judgment
and comparison, need hardly be enlarged upon.” 2030 e great and deep difficulty that contained within itself its own solution was not, finally, the
bomb.
It was the inequality of men and nations.
e bomb in its ultimate
manifestation, nuclear holocaust, would eliminate that inequality by
destroying rich and poor, democratic and totalitarian alike in one final
apocalypse.
It followed complementarily that the opening up of the world
necessary to prevent (or reverse) an arms race would also progressively
expose and alleviate inequality, but in the direction of life, not death:
Within any community it is only possible for the citizens to strive together
for common welfare on the basis of public knowledge of the general
conditions of the country.
Likewise, real co-operation between nations on
problems of common concern presupposes free access to all information
of importance for their relations.
Any argument for upholding barriers of
information and intercourse, based on concern for national ideals or
interests, must be weighed against the beneficial effects of common
enlightenment and the relieved tension resulting from such openness.
2031
at statement, from an open letter Bohr wrote to the United Nations in
1950, is preceded by another, a vision of a world evolved to the relative
harmony of the nations of Scandinavia that once confronted each other and
the rest of Europe as aggressively and menacingly as the Soviet Union and
the United States had come by 1950 to do.
Notice that Bohr does not
propose a world government of centralized authority but a consortium: “An
open world where each nation can assert itself solely by the extent to which
it can contribute to the common culture and is able to help others with
experience and resources must be the goal to put above everything else.” 2032
And most generally and profoundly: “e very fact that knowledge is itself
the basis for civilization points directly to openness as the way to overcome
the present crisis.” 2033
Such an effort would begin with the United States, Bohr suggested to
Roosevelt in the summer of 1944, because the United States had achieved
clear advantage: “e present situation would seem to offer a most
favourable opportunity for an early initiative from the side which by good
fortune has achieved a lead in the efforts of mastering mighty forces of
nature hitherto beyond human reach.” Concessions would demonstrate
goodwill; “indeed, it would appear that only when the question is taken
up...
of what concessions the various powers are prepared to make as their
contribution to an adequate control arrangement, [will it] be possible for
any one of the partners to assure themselves of the sincerity of the intentions
of the others.” 2034
e untitled memorandum Bohr prepared for Franklin Roosevelt in
Washington in 1944 went to Felix Frankfurter for review on July 5 along
with a cover letter apologizing for its inadequacies.
Bohr worried through
the hot night and composed another apology the next day: “I have had
serious anxieties,” he confided, “that [the memorandum] may not
correspond to your expectations and perhaps not at all be suited for the
purpose.” 2035 Frankfurter had the good sense to recognize the document’s
merit—it is still the only comprehensive and realistic charter for a
postnuclear world—and about a week later told Bohr he had handed it to
the President.
Bohr and his son le Washington soon aer, on a Friday in
mid-July, to work at Los Alamos, understanding that Roosevelt would
arrange a meeting in good time.
at time came in August as the President prepared to meet the Prime
Minister in Quebec.
Bohr returned to the U.S.
capital; “on August 26th at 5
p.m.,” he writes, “B was received by the President in the White House in a
completely private manner.” 2036 Roosevelt “was very cordial and in excellent
spirits,” says Aage Bohr, as well he might have been aer the rapid advances
of the Allied armies across Europe.2037 He had read Bohr’s memorandum;
he “most kindly gave B an opportunity to explain his views and spoke in a
very frank and encouraging manner about the hopes he himself
entertained.” 2038 FDR liked to charm; he charmed Bohr with stories, Aage
Bohr recounts:
Roosevelt agreed that an approach to the Soviet Union of the kind
suggested must be tried, and said that he had the best hopes that such a
step would achieve a favourable result.
In his opinion Stalin was enough
of a realist to understand the revolutionary importance of this scientific
and technical advance and the consequences it implied.
Roosevelt
described in this connection the impression he had received of Stalin at
the meeting in Teheran, and also related humorous anecdotes of his
discussion and debates with Churchill and Stalin.
He mentioned that he
had heard how the negotiations with Churchill in London had gone, but
added that the latter had oen reacted in this way at the first instance.
However, Roosevelt said, he and Churchill always managed to reach
agreement, and he thought that Churchill would eventually come around
to sharing his point of view in this matter.
2039 He would discuss the
problems with Churchill at their forthcoming meeting and hoped to see
my father soon aerwards.
e interview lasted an hour and a half.
To Robert Oppenheimer in 1948
Bohr reported a more specific commitment from the President: he “le with
Professor Bohr the impression,” Oppenheimer writes, “that, aer discussion
with the Prime Minister, he might well ask [Bohr] to undertake an
exploratory mission to the Soviet Union.
”2040
“It is hardly necessary to mention the encouragement and gratitude my
father felt aer his talk with Roosevelt,” Aage Bohr goes on; “these were days
filled with the greatest optimism and expectation.
”2041 Bohr saw Frankfurter
in Boston and told him about the meeting.
Frankfurter suggested Bohr
restate his case in a thank-you note, which Bohr managed to compress into
one long page by September 7.
Frankfurter passed it to Roosevelt’s aide.
Bohr settled in eagerly to wait.
e two heads of state saved their Tube Alloy discussions for the end of
the conference, late September, when they retreated to Roosevelt’s estate in
the Hudson Valley at Hyde Park.
“is was another piece of black comedy,”
writes C.
P.
Snow.
“...
Roosevelt surrendered without struggle to Churchill’s
view of Bohr.
”2042 e result was a secret aide-memoire, obviously of
Churchill’s composition, that misrepresented Bohr’s proposals, repudiated
them and recorded for the first time the Anglo-American position on the
new weapon’s first use:
e suggestion that the world should be informed regarding tube alloys,
with a view to an international agreement regarding its control and use, is
not accepted.
e matter should continue to be regarded as of the utmost
secrecy; but when a “bomb” is finally available, it might perhaps, aer
mature consideration, be used against the Japanese, who should be
warned that this bombardment will be repeated until they surrender.
2043
2.
Full collaboration between the United States and the British
Government in developing tube alloys for military and commercial
purposes should continue aer the defeat of Japan unless and until
terminated by joint agreement.
3.
Enquiries should be made regarding the activities of Professor Bohr
and steps taken to ensure that he is responsible for no leakage of
information particularly to the Russians.
e next day, September 20, Churchill wrote Cherwell in high dudgeon:
e President and I are much worried about Professor Bohr.
How did he
come into this business?
He is a great advocate of publicity.
He made an
unauthorized disclosure to Chief Justice [sic] Frankfurter who startled the
President by telling him he knew all the details.
He says he is in close
correspondence with a Russian professor, an old friend of his in Russia to
whom he has written about the matter and may be writing still.
e
Russian professor has urged him to go to Russia in order to discuss
matters.
What is all this about?
It seems to me Bohr ought to be confined
or at any rate made to see that he is very near the edge of mortal crimes.
I
had not visualized any of this before....
I do not like it at all.
2044
Anderson, Halifax and Cherwell all defended Bohr to Churchill aer the
Hyde Park outburst, as did Bush and Conant to FDR.
e Danish laureate
was not confined.
But neither was he invited to meet again with the
President of the United States.
ere would be no exploratory mission to the
USSR.
How much the world lost that September is immeasurable.
e
complementarity of the bomb, its mingled promise and threat, would not be
canceled by the decisions of heads of state; their frail authority extends not
nearly so far.
Nuclear fission and thermonuclear fusion are not acts of
Parliament; they are levers embedded deeply in the physical world,
discovered because it was possible to discover them, beyond the power of
men to patent or to hoard.
* * *
Edward Teller had arrived at Los Alamos in the April of its founding in 1943
prepared to participate fully in its work.
He was then thirty-five years old,
dark, with bushy, mobile black eyebrows and a heavy, uneven step;
“youthful,” Stanislaw Ulam remembers, “always intense, visibly ambitious,
and harboring a smouldering passion for achievement in physics.
He was a
warm person and clearly desired friendship with other physicists.” 2045
Teller’s son Paul, his first child, had been born in February.
e Tellers had
shipped to the primitive New Mexico mesa two machines they considered
vital to their peace of mind, a Steinway concert grand piano Mici Teller had
bought for her husband for two hundred dollars at a Chicago hotel sale and
a new Bendix automatic washer.
ey were assigned an apartment; the
Steinway nearly filled the living room.
Teller had striven on behalf of nuclear energy since Bohr’s first public
announcement of the discovery of fission in Washington in 1939.
He had
helped Robert Oppenheimer organize Los Alamos and recruit its staff.
He
expected to contribute to the planning of the new laboratory’s program and
he did.
“It was essential that the whole laboratory agree on one or a very few
major lines of development,” writes Hans Bethe, “and that all else be
considered of low priority.
Teller took an active part in the decision on what
were to be the major lines....
A distribution of work among the members
of the eoretical Division was agreed upon in a meeting of all scientists of
the division and Teller again had a major voice.
”2046
But Teller had received no concomitant administrative appointment that
April, and the omission aggrieved him.
He was qualified to lead the
eoretical Division; Oppenheimer appointed Hans Bethe instead.
He was
qualified to lead a division devoted to work toward a thermonuclear fusion
weapon, a Super, but no such division was established.
e laboratory had
decided at its opening conference, and the Lewis committee had affirmed in
May, that thermonuclear research should be restricted largely to theoretical
studies and held to distant second priority behind fission: an atomic bomb,
since it would trigger any thermonuclear arrangement, necessarily came
first; there was a war on and manpower was limited.
2047
“at I was named to head the [eoretical] division,” Bethe comments,
“was a severe blow to Teller, who had worked on the bomb project almost
from the day of its inception and considered himself, quite rightly, as having
seniority over everyone then at Los Alamos, including Oppenheimer.” Bethe
believed he was chosen because his “more plodding but steadier approach to
life and science would serve the project better at that stage of its
development, where decisions had to be adhered to and detailed calculations
had to be carried through, and where, therefore, a good deal of
administrative work was inevitable.” 2048 Teller saw his old friend’s steadier
approach differently: “Bethe was given the job to organize the effort and, in
my opinion, in which I may well have been wrong, he overorganized it.
It
was much too much of a military organization, a line organization.
”2049 On
the other hand, Teller has repeatedly praised Oppenheimer’s direction of Los
Alamos, direction which included Bethe’s appointment and ratified Bethe’s
decisions:
roughout the war years, Oppie knew in detail what was going on in
every part of the Laboratory.
He was incredibly quick and perceptive in
analyzing human as well as technical problems.
Of the more than ten
thousand people who eventually came to work at Los Alamos, Oppie
knew several hundred intimately, by which I mean that he knew what
their relationships with one another were and what made them tick.
He
knew how to organize, cajole, humor, soothe feelings—how to lead
powerfully without seeming to do so.
He was an exemplar of dedication, a
hero who never lost his humanness.
Disappointing him somehow carried
with it a sense of wrongdoing.
Los Alamos’ amazing success grew out of
the brilliance, enthusiasm and charisma with which Oppenheimer led
it.2050
“I believe maybe [Teller] resented my being placed on top of him,” Bethe
concludes.
“He resented even more that there would be an end to free and
general discussion....
2051 He resented even more that he was removed [by
lack of administrative contact] from Oppenheimer.”
e theoretical complexity of the Super challenged Teller as the fission
bomb had not; it also offered a line of work along which he might lead.
“When Los Alamos was established in the spring of 1943,” he writes and the
technical history of the laboratory confirms, “the exploration of the Super
was among its objectives.” 2052, 2053 He accepted the postponement of that exploration through the summer of 1943, helping Bethe with the more
immediate problem of developing means to calculate the critical mass and
nuclear efficiency of various bomb designs.
During the summer,
experimental studies at Purdue found that the fusion reaction cross section
for deuterium was much larger than expected; Teller cited that result to the
Purdue Los Alamos Governing Board in September to propose renewing the
Super investigation.
en John von Neumann arrived on the Hill to endorse
and extend Seth Neddermeyer’s implosion work and for a few months Teller
was caught up in reconnoitering that new territory.
Emilio Segrè won a new workshop that 1943 autumn.
At Berkeley he had
measured the rate of spontaneous fission—naturally occurring fission
without neutron bombardment—in uranium and plutonium.
e
measurements were difficult because the rates were low for the small
samples Segrè had to use, but they were crucial.
ey determined how
cleansed of light-element impurities the bomb cores would have to be—
there was no point in purifying past the spontaneous background—and they
determined how fast the gun assemblies would have to fire to avoid
predetonation.
Segrè moved off the Los Alamos mesa to protect his new and
more capacious measuring instruments from the radiation other
experiments generated there:
At this time I acquired a special small laboratory for measuring
spontaneous fission, the like of which I have never seen before or since.
It
was a log cabin that had been occupied by a ranger and it was located in a
secluded valley a few miles from Los Alamos.
It could be reached only by
a jeep trail that passed through fields of purple and yellow asters and a
canyon whose walls were marked with Indian carvings.
On this trail we
once found a large rattlesnake.
e cabin-laboratory, in a grove shaded by
huge broadleaf trees, occupied one of the most picturesque settings one
could dream of.
2054
In December at this Pajarito Canyon field station Segrè made a significant
discovery.
e spontaneous fission rate for natural uranium was much the
same at the field station as at Berkeley, but at the field station the rate was
seemingly higher for U235.
Segrè deduced that cosmic-ray neutrons, which
were usually too slow to fission U238 but effective to fission U235, caused
the difference.
Cosmic rays batter neutrons from the upper reaches of the
atmosphere and the field station was 7,300 feet nearer that region than was
sea-level Berkeley.
Shield out such stray neutrons and the U235 bomb core
could be purified less rigorously than they had assumed.
Predetonation
would be less likely: the gun that assembled the U235 to critical mass would
need less muzzle velocity and could be significantly shorter and lighter.
us
was Little Boy engendered, in Man’s modest brother, a gun assembly six
feet long instead of seventeen that would weigh less than 10,000 pounds, an
easy load for a B-29: in a log cabin in a grove beyond fields of bright asters,
up a trail visited by rattlesnakes.
Gun research was already advanced.
“e first task of the gun group,”
Edwin McMillan remembers, “was to set up a test stand where experiments
could be done.
You have to have a gun emplacement, and a gun, and a sand
butt, which is nothing but a huge box full of sand that you fire projectiles
into so that you can find the pieces aerwards, and because there might be
somebody else out there.
”2055 e site they chose was Anchor Ranch, a
former working ranch three miles southwest of the mesa that the Army had
bought as part of the reservation; they fired the first shot on September 17,
1943.
Until the following March the group used a three-inch Navy anti-aircra
gun fitted with unrifled barrels.
With it they tested propellants—eventually
choosing cordite—and studied scale-model projectiles and targets.
Knowing
that the uranium bullet would complete a critical assembly they decided that
it should not impact upon the target core but pass freely through; within
microseconds of its arrival at spherical configuration it would in any case
have vaporized.2056
From the beginning the plutonium gun with its nearly unattainable
muzzle velocity of 3,000 feet per second had been a gamble.
When von
Neumann that autumn celebrated the advantages of implosion the
Governing Board gave the novel approach its strong endorsement.
rough
the fall and early winter of 1943 Neddermeyer’s experiments made only slow
progress, however.
He added few men to his group.
He continued to work
methodically with metal cylinders wrapped with solid slabs of high
explosive.
By spacing several detonators symmetrically around the wrap he
could start implosion simultaneously at different points on the HE surface.
From each point of detonation a detonation wave shaped like an expanding
bubble would travel inward toward the metal cylinder; by varying the
spacing of the detonators and the thickness of the HE Neddermeyer hoped
to find a configuration that smoothed the convex, multiple shock waves to
one uniform cylindrical squeeze.
He was working to the same end with
small metal balls, scale models of an eventual bomb core.
But “the first
successful HE flash photographs of imploding cylinders,” notes the Los
Alamos technical history, “showed that there were...
very serious
asymmetries in the form of jets which traveled ahead of the main mass.
2057
A number of interpretations of these jets were proposed, including the
possibility that they were optical illusions.” ey were all too real.
“Absolutely awful results,” says Bethe.2058 Oppenheimer decided
Neddermeyer needed help.
Groves agreed.
Conant knew just the man.
“Everything in books [about the Manhattan Project] looks so simple, so
easy, and everybody was friends with everybody,” George Kistiakowsky told
an audience wryly long aer the war.2059 He remembered a different Los
Alamos.
e tall, outspoken Ukrainian-born Harvard chemist had begun
studying explosives for the National Defense Research Committee in 1940;
“by 1943 I thought I knew something about them.” What he knew about
them was original and unorthodox: “that they could be made into precision
instruments, a view which was very different from that of military
ordnance.
”2060 He had already won von Neumann to his view, which had
prepared the Hungarian mathematician in turn to endorse the precision
instrument of implosion.2061 Conant similarly trusted Kistiakowsky’s
judgment.
In 1941 Conant had abandoned his skepticism toward the atomic
bomb because of Kistiakowsky; now the explosives expert found the
Harvard president seeking his help to advance Neddermeyer’s work:
I began going to Los Alamos as a consultant in the Fall of 1943, and then
pressure was put on me by Oppenheimer and General Groves and
particularly Conant, which really mattered, to go there on full time.
I
didn’t want to, partly because I didn’t think the bomb would be ready in
time and I was interested in helping win the war.
I also had what looked
like an awfully interesting overseas assignment all fixed up for myself.
Well, instead, unwillingly, I went to Los Alamos.
at gave me a
wonderful opportunity to act as a reluctant bride throughout the life of
the project, which helped at times.
2062
Kistiakowsky arrived in late January 1944 and took up residence in a small
stone cabin that had been the Ranch School’s pump house, an
accommodation he negotiated in preference to the men’s dormitory—he was
forty-four years old and divorced.
He quickly discovered, as he suspected,
that everything was not easy and everybody was not friends:
Aer a few weeks...
I found that my position was untenable because I
was essentially in the middle trying to make sense of the efforts of two
men who were at each other’s throats.
One was Captain [Deke] Parsons
who tried to run his division the way it is done in military establishments
—very conservative.
e other was, of course, Seth Neddermeyer, who
was the exact opposite of Parsons, working away in a little corner.2063 e
two never agreed about anything and they certainly didn’t want me
interfering.
While Kistiakowsky struggled with that dilemma the theoreticians began to
glimpse how a successful implosion mechanism might be designed.
e previous spring the Polish mathematician Stanislaw Ulam, then
thirty-four years old and a member of the faculty at the University of
Wisconsin, had found himself unhappy merely teaching in the midst of war:
“It seemed a waste of my time; I felt I could do more for the war effort.” 2064
He had noticed that letters from his old friend John von Neumann oen
bore Washington rather than Princeton postmarks and deduced that von
Neumann was involved in war work; now he wrote asking for advice.
Von
Neumann proposed they meet between trains in Chicago to talk and turned
up impressively chaperoned by two bodyguards.
Eventually Hans Bethe sent
along an official invitation.
In the winter of 1943 Ulam and his wife
Françoise, who was then two months pregnant, rode the Sante Fe Chief to
New Mexico as so many others had done before them.
“e sun shone
brilliantly, the air was crisp and heady, and it was warm even though there
was a lot of snow on the ground—a lovely contrast to the rigors of winter in
Madison.” 2065
e day of his arrival Ulam met Edward Teller for the first time—he was
assigned to Teller’s group—who “talked to me on that first day about a
problem in mathematical physics that was part of the necessary theoretical
work in preparation for developing the idea of a ‘super’ bomb.” 2066 Teller’s
preemption of Ulam’s first days at Los Alamos for Super calculations was
symptomatic of the discord that had been widening between him and Hans
Bethe, who needed every available theoretical physicist and mathematician
to concentrate on the difficult problem of implosion.
Teller had contributed
enthusiastically and crucially to the most interesting part of the work.
“However,” Bethe complains, “he declined to take charge of the group which
would perform the detailed calculations on the implosion.
Since the
theoretical division was very shorthanded, it was necessary to bring in new
scientists to do the work that Teller declined to do.
”2067 at was one reason
the British team had been invited to Los Alamos.
Teller recalls no specific refusal.
“[Bethe] wanted me to work on
calculational details at which I am not particularly good,” he counters,
“while I wanted to continue not only on the hydrogen bomb, but on other
novel subjects.” 2068
e Los Alamos Governing Board reevaluated the Super once again in
February 1944, learning that despite deuterium’s more favorable cross
section it would still be difficult to ignite.
A Super would almost certainly
require tritium.
e small tritium samples studied so far had been
transmuted in a cyclotron by bombarding lithium with neutrons.
Large-
scale tritium production, like large-scale plutonium production, would
require production reactors, but the piles at Hanford were unfinished and
previously committed.
“Both because of the theoretical problems still to be
solved and because of the posssibility that the Super would have to be made
with tritium,” reports the Los Alamos technical history, “it appeared that the
development would require much longer than originally anticipated.” Work
could continue—the Super was too portentous a weapon to ignore—but
only to the extent that it “did not interfere with the main program.
”2069
Von Neumann soon draed Ulam to help work out the hydrodynamics of
implosion.
e problem was to calculate the interactions of the several
shock waves as they evolved through time, which meant trying to reduce the
continuous motion of a number of moving, interacting surfaces to some
workable mathematical model.
“e hydrodynamical problem was simply
stated,” Ulam comments, “but very difficult to calculate—not only in detail,
but even in order of magnitude.
”2070
He remembers in particular a long discussion early in 1944 when he
questioned “all the ingenious shortcuts and theoretical simplifications which
von Neumann and other...
physicists suggested.” He had argued instead for
“simpleminded brute force—that is, more realistic, massive numerical
work.
”2071 Such work could not be done reliably by hand with desktop
calculating machines.
Fortunately the laboratory had already ordered IBM
punchcard sorters to facilitate calculating the critical mass of odd-shaped
bomb cores.
e IBM equipment arrived early in April 1944 and the
eoretical Division immediately put it to good use running brute-force
implosion numbers.
Hydrodynamic problems, detailed and repetitious, were
particularly adaptable to machine computation; the challenge apparently set
von Neumann thinking about how such machines might be improved.
en a member of the newly arrived British mission made a proposal that
paid his mission’s way.
James L.
Tuck was a tall, rumpled Cherwell protégé
from Oxford who had worked in England developing shaped charges for
armor-piercing shells.
A shaped charge is a charge of high explosive
arranged in such a way—usually hollowed out like an empty ice cream cone
with the open end pointed forward—that its normally divergent, bubble-
shaped shock wave converges into a high-speed jet.
Such a ferocious jet can
punch its way through the thick armor of a tank to spray death inside.
It had just become clear from theoretical work that the several diverging
shock waves produced by multiple detonators in Neddermeyer’s
experiments reinforced each other where they collided and produced points
of high pressure; such pressure nodes in turn caused the jets and
irregularities that spoiled the implosion.
Rather than continue trying to
smooth out a colliding collection of divergent shock waves, Tuck sensibly
proposed that the laboratory consider designing an arrangement of
explosives that would produce a converging wave to begin with, fitting the
shock wave to the shape it needed to squeeze.
Such explosive arrangements
were called lenses by analogy with optical lenses that similarly focus light.
No one wanted to tackle anything so complex so late in the war.
Geoffrey
Taylor, the British hydrodynamicist, arrived in May to offer further insight
into the problem.
He had developed an understanding of what came to be
called Raleigh-Taylor instabilities, instabilities formed at the boundaries
between materials.
Accelerate heavy material against light material, he
demonstrated mathematically, and the boundary between the two will be
stable.
But accelerate light material against heavy material and the boundary
between the two will be unstable and turbulent, causing the two materials to
mix in ways extremely difficult to predict.
High explosive was light
compared to tamper.
All of the tamper materials under consideration except
uranium were significantly lighter than plutonium.
Raleigh-Taylor
instabilities would constrain subsequent design.
ey would also make it
difficult to predict bomb yield.
As the IBM results clarified shock-wave behavior the physicists began
seriously to doubt if a uniform wrap of HE could ever be made to produce a
symmetrical explosion.
Complex though explosive lenses might be, they
were apparently the only way to make implosion work.
Von Neumann
turned to their formulation.
“You have to assume that you can control the
velocity of the detonation wave in a chemical explosive very accurately,”
Kistiakowsky explains, “so if you start the wave at certain points by means of
detonators you can predict exactly where it will be at a given time.
en you
can design the charge.” 2072 It was soon clear that the velocity of the
converging shock waves from the several explosive lenses that would
surround the bomb core could vary by no more than 5 percent.
at was the
demanding limit within which von Neumann designed and Kistiakowsky,
Neddermeyer and their staffs began to work.
2073
In the spring of 1944 the two difficult personal conflicts—between Teller
and Bethe and between Kistiakowsky and Neddermeyer—forced
Oppenheimer to intervene.
First, Bethe writes, Teller withdrew from fission
development:
With the pressure of work and lack of staff, the eoretical Division could
ill afford to dispense with the services of any of its members, let alone one
of such brilliance and high standing as Teller.2074 Only aer two failures to
accomplish the expected and necessary work, and only on Teller’s own
request, was he, together with his group, relieved of further responsibility
for work on the wartime development of the atomic bomb.
A letter from Oppenheimer to Groves on May 1, 1944, seeking to replace
Teller with Rudolf Peierls, corroborates Bethe’s account: “ese calculations,”
it says in part, “were originally under the supervision of Teller who is, in my
opinion and Bethe’s, quite unsuited for this responsibility.
Bethe feels that he
needs a man under him to handle the implosion program.” It was,
Oppenheimer notes, a question of the “greatest urgency.
”2075
Ulam remembers that Teller threatened to leave.
Oppenheimer stepped in
then to save him for the project.
He encouraged Teller to give himself over to
the Super—encouragement, Teller wrote in 1955, perhaps disingenuously,
that he needed to move him on from the immediate task at hand:
Oppenheimer...
continued to urge me with detailed and helpful advice
to keep exploring what lay beyond the immediate aims of the laboratory.
is was not easy advice to give, nor was it easy to take.
It is easier to
participate in the work of the scientific community, particularly when a
goal of the highest interest and urgency has been clearly defined.
Every
one of us considered the present war and the completion of the A-bomb
as the problems to which we wanted to contribute most.
Nevertheless,
Oppenheimer...
and many of the most prominent men in the laboratory
continued to say that the job at Los Alamos would not be complete if we
should remain in doubt whether or not a thermonuclear bomb was
feasible.2076
To that end Oppenheimer in May discussed tritium production with Groves
and Du Pont’s Crawford Greenewalt.
e chemical company had built a
pilot-scale air-cooled pile at Oak Ridge that produced neutrons to spare;
Greenewalt agreed to put some of them to use bombarding lithium.
Teller departed the eoretical Division.
Rudolf Peierls took his place.
Oppenheimer arranged then to meet with Teller weekly for an hour of
freewheeling talk.
at was a remarkable concession when the laboratory
was working overtime six days a week to build a bomb before the end of the
war.
Oppenheimer may well have thought Teller’s imaginative originality
worth it.
He also understood his extreme sensitivity to slight.
Later that
summer, when Cherwell visited Los Alamos, Oppenheimer gave a party and
inadvertently failed to invite Peierls, who was deputy head of the British
mission under James Chadwick.
Oppenheimer sought out Peierls the next
day and apologized, adding: “But there is an element of relief in this
situation: it might have happened with Edward Teller.” 2077
George Kistiakowsky adjusted himself to Seth Neddermeyer until he felt
that not only he but also the project was suffering; then he reviewed his
alternatives and, on June 3, wrote Oppenheimer a memorandum.
2078 He and
Neddermeyer had established a certain modus vivendi, he wrote, but it was
not what he had been asked to do, which was to administer implosion work
while Neddermeyer did the science, and it was “not based on mutual
confidence and a friendly give-and-take.”
He proposed three possible solutions.
He could resign, the solution he
thought best and fairest to Neddermeyer.
Or Neddermeyer could resign, but
that would disturb his staff and slow the work; it would also be unfair to a
good physicist.
Or Neddermeyer could “take over more vigorous scientific
and technical direction of the project but dissociate himself completely from
all administrative and personnel matters.”
Oppenheimer had come to value Kistiakowsky too highly to choose any of
these alternatives.
He proposed a fourth.
Kistiakowsky worked out the
details and the men met painfully to present it to Neddermeyer on a
ursday evening in mid-June: Kistiakowsky would assume full
responsibility for implosion work as an associate division leader under
Parsons.
Neddermeyer and Luis Alvarez, recently arrived from Chicago,
would become senior technical advisers.
Neddermeyer le the meeting
early, as well he might.
“I am asking you to accept the assignment,”
Oppenheimer wrote him the same evening.
“...
In behalf of the success of
the whole project, as well as the peace of mind and effectiveness of the
workers in the H.
E.
program, I am making this request of you.
I hope you
will be able to accept it.” 2079 With enduring bitterness Neddermeyer did.
* * *
e air-cooled, pilot-scale reactor at Oak Ridge had gone critical at five
o’clock in the morning on November 4, 1943; the loading crews, realizing
during the night that they were nearing criticality sooner than expected, had
enjoyed rousting Arthur Compton and Enrico Fermi out of bed at the Oak
Ridge guest house to witness the event.
e pile, which was designated X-10,
was a graphite cube twenty-four feet on a side drilled with 1,248 channels
that could be loaded with canned uranium-metal slugs and through which
large fans blew cooling air.
e channels extended for loading through the
seven feet of high-density concrete that composed the pile face; at the back
they opened onto a subterranean pool like the pools planned for Hanford
into which irradiated slugs could be pushed to shield them until they lost
their more intense short-term radioactivity.
Chemists then processed the
slugs in a remote-controlled pilot-scale separations plant using the chemical
separation processes Glenn Seaborg and his colleagues had developed at
ultramicrochemical scale in Chicago.
A few days before Compton moved to Oak Ridge to supervise the X-10
operation, at the end of November, workers discharged the first five tons of
irradiated uranium from the pile.
Chemical separations began the following
month.
By the summer of 1944 batches of plutonium nitrate containing
gram quantities of plutonium had begun arriving at Los Alamos.
e man-
made element was quickly used and reused in extensive experiments to
study its unfamiliar chemistry and metallurgy—more than two thousand
separate experiments by the end of the summer.
2080
Not chemistry or metallurgy but physics nearly condemned the
plutonium bomb to failure that summer.
More than a year previously Glenn
Seaborg had warned that the isotope Pu240 might form along with desirable
Pu239 when uranium was irradiated to make plutonium.
Pu240, an even-
numbered isotope, was likely to exhibit a much higher rate of spontaneous
fission than Pu239.
e plutonium samples Emilio Segrè had studied at his
isolated log-cabin laboratory fissioned spontaneously at acceptable rates.
ey had been transmuted from uranium in one of the Berkeley cyclotrons.
U238 needed one neutron to transmute to Pu239; for Pu240 it required two,
and far more neutrons bombarded the uranium slugs cooking in the X-10
pile than a cyclotron could generate.
When Segrè measured the spontaneous
fission rate of the X-10 plutonium he found it much higher than the
Berkeley rate.
e rate for Hanford plutonium, which would be exposed to
an even heavier neutron flux, was likely to be higher still.
at meant they
would not need to cleanse the plutonium so thoroughly of light-element
impurities.
But it also signaled catastrophe.
ey could not use a gun to
assemble a critical mass of such stuff: approaching each other even at 3,000
feet per second, the plutonium bullet and target would melt down and fizzle
before the two parts had time to join.
Oppenheimer alerted Conant on July 11.
e two men met with
Compton, Groves, Nichols and Fermi in Chicago six days later and the next
day Oppenheimer wrote Groves to confirm their conclusions.
Pu240 was
apparently long-lived, and since the two isotopes were elementally identical
it could not be removed chemically.
ey had not considered separating
Pu239 from Pu240 electromagnetically.
Such an effort with isotopes that
differed by only one mass unit and were highly toxic would dwarf the vast
calutron operation at Oak Ridge and could not possibly be accomplished in
time to influence the outcome of the war.
“It appears reasonable,”
Oppenheimer ended, “to discontinue the intensive effort to achieve higher
purity for plutonium and to concentrate’ attention on methods of assembly
which do not require a low neutron background for their success.
At the
present time the method to which an over-riding priority must be assigned
is the method of implosion.
”2081
at necessity was painful, as the Los Alamos technical history makes
clear: “e implosion was the only real hope, and from current evidence not
a very good one.
”2082 Oppenheimer agonized over the problem to the point
that he considered resigning his directorship.
Robert Bacher, the sturdy
leader of the Experimental Physics Division, took long walks with him in
those days to share his pain and eventually dissuaded him.
ere was no one
else who could do the job, Bacher argued; without Oppenheimer there
would be no bomb in time to shorten the war and save lives.
Action changed Oppenheimer’s mood.
“e Laboratory had at this time
strong reserves of techniques, of trained manpower, and of morale,” says the
technical history.
2083 “It was decided to attack the problems of the implosion
with every means available, ‘to throw the book at it.’ ” Going over the
prospects with Bacher and Kistiakowsky, Oppenheimer decided to carve
two new divisions out of Parsons’ Ordnance Division: G (for Gadget) under
Bacher to master the physics of implosion and X (for eXplosives) under
Kistiakowsky to perfect explosive lenses.
e Navy captain howled,
Kistiakowsky remembers:
[Oppenheimer] called a big meeting of all the group heads, and there he
sprang on Parsons the fact that I had plans for completely re-designing
the explosives establishment.
Parsons was furious—he felt that I had by-
passed him and that was outrageous.
I can understand perfectly how he
felt but I was a civilian, so was Oppie, and I didn’t have to go through
him....
From then on Parsons and I were not on good terms.
He was
extremely suspicious of me.
2084
Parsons had his hands full in any case designing the uranium gun, Little
Boy, and arranging its eventual use.
Oppenheimer prevailed: they would
throw the book at implosion.
In the months ahead the laboratory, which had
swollen to 1,207 full-time employees by the previous May 1, would once
again double and redouble in size.
2085
* * *
Philip Abelson, the young Berkeley physicist to whom Luis Alvarez had run
from his barber chair in January 1939 to announce the news of fission, had
moved to the Naval Research Laboratory in 1941 to work on uranium
enrichment for the Navy and had made valuable progress independently of
the Manhattan Project in the intervening years.
e Navy was interested in
nuclear power as a motive force for submarines, to extend their range and to
allow them to travel farther submerged.
But a pile of the sort Fermi would
build would be unwieldy; “it had become pretty obvious,” Abelson recalls,
“that a reactor fueled with natural uranium would be big as a barn.” 2086
Increase the ratio of U235 to U238 in the reactor fuel—enrich the uranium
—and the reactor could be correspondingly smaller; with enough
enrichment, small enough to fit inside the hull of a submarine in the space
previously reserved for diesel engines, batteries and fuel.
Enrichment and separation are different goals, but the same technologies
achieve them.
Abelson began work by looking up the record of those
technologies.
Gaseous barrier diffusion was under study then at Columbia,
electromagnetic separation at Berkeley, centrifuge separation at the
University of Virginia.
Abelson decided to try a process that had been
pioneered in Germany before the war: liquid thermal diffusion (using glass
tubes, Otto Frisch had experimented unsuccessfully with a similar process,
gaseous thermal diffusion, at Birmingham).
ermal diffusion relied on the
tendency of lighter isotopes to diffuse toward a hotter region while heavier
isotopes diffused toward a colder region.
e mechanism for driving such
diffusion could be simple: a hot pipe inside a cold pipe with liquid uranium
hexafluoride flowing between the two pipe walls.
Depending on the
difference in temperature and the spacing between the two pipes more or
less diffusion would occur.
At the same time the heating and cooling of the
hex would start a convection current flowing up the hot pipe wall and down
the cold.
at would bring the U235-enriched fluid to the top of the column
where it could be tapped off.
To increase the enrichment a number of
columns could be connected in series to make a cascade like the cascade of
barrier tanks planned for K-25.
Abelson’s first technical contribution, in 1941, was inventing a relatively
cheap way to make uranium hexafluoride.
He processed the first hundred
kilograms of hex produced in the United States.
For the nominal sum of one
dollar the Army contracted to borrow his patented process for Oak Ridge.
He never saw the dollar.
2087
e experimental thermal-diffusion columns Abelson built at the Naval
Research Laboratory in 1941 and 1942 were 36 feet tall, each consisting of
three pipes arranged one inside the other.
e hot inner pipe, 1¼ inches in
diameter, carried high-pressure steam at about 400° F.
Surrounding that
nickel pipe a copper pipe contained the liquid hex.
e critical spacing
between the two pipes where the hex flowed measured only about one-tenth
of an inch.
Surrounding both pipes a 4-inch pipe of galvanized iron carried
water at about 130°, just above hex’s melting point, to cool the hex.
2088
Pumps that circulated the water were the only moving parts.
“e
apparatus was run continuously with no shut down or break down what so
ever,” Abelson reported to the Navy early in 1943.
“Indeed, so constant were
the various temperatures and operating characteristics that practically no
attention was required to insure successful operation.
Many days passed in
which operating personnel did not touch any control device.” 2089 To stop the
flow of the hex out of a column Abelson simply dipped the bend of a U-
shaped metal drain tube into a bucket of dry ice and alcohol, which froze the
hex and plugged the tube.
A flame to warm the tube started the flow again.
Abelson’s January 4, 1943, report, submitted jointly with his NRL
colleague Ross Gunn, indicated that uranium could be enriched within a
single thermal-diffusion column from its natural U235 content of 0.7
percent up to 1 percent or better.
With several thousand columns connected
in series Abelson thought he could produce 90 percent pure U235 at the rate
of 1 kilogram per day at a total construction cost of no more than $26
million.
Ninety percent purity was entirely sufficient to make a bomb.
(at
estimate proved optimistic, however, and equilibrium time for such a
cascade appeared to be as long as 600 days.)
Another choice, more in keeping with the Navy’s interest in submarine
propulsion, emphasized quantity enrichment rather than quality.
Abelson
proposed building a plant of 300 48-foot columns operating in parallel to
make large amounts of slightly enriched uranium immediately.
Chicago
could use such slightly enriched uranium to advance its pile work, Abelson
thought.
He did not yet know that CP-1 had gone critical just one month
before his report.
“Information concerning the many experiments
performed by [the Chicago] workers in the last six months has been denied
to us,” he complained.
“It is vitally necessary that there be an exchange of
technical information if proper plans are to be made for future plants.” 2090
e NRL had been the first research center Groves visited when he took
charge of the Manhattan Project in September 1942.
Months before then,
Franklin Roosevelt had specifically instructed Vannevar Bush to exclude the
Navy from atomic bomb development.
Groves followed the NRL’s research
and Bush encouraged its funding through the Military Policy Committee.
But by 1943 the official flow of information on nuclear energy research ran
from the Navy to the Army one-way only.
Unofficially, however, several of Groves’ compartments leaked.
In
November 1943 the Navy authorized Abelson to build his 300-column plant.
He had searched for a sufficient source of steam—thermal diffusion used
volcanic magnitudes of steam, one reason the Manhattan Project had chosen
not to pursue it—and located the Naval Boiler and Turbine Laboratory at
the Philadelphia Navy Yard.
“ey were testing good-sized boilers that
would go into ships,” Abelson says.
“ey had the capability of making
quantities of steam at a thousand pounds per square inch and they had Navy
people standing twenty-four-hour watches to deliver the steam.” 2091 e
boiler laboratory’s waste steam would supply his 300-column plant, but
before scaling up that far he planned to test his design by building and
operating only the first 100 columns.
Construction began in January 1944,
with completion scheduled for July.
By now Abelson knew more about the
Manhattan Project.2092 He knew that the barriers which Houdaille-Hershey
had been stripped and reequipped to manufacture were not yet passing
inspection and that K-25, the gaseous-diffusion plant, was therefore
woefully behind schedule.
He knew Los Alamos had been founded with
Robert Oppenheimer as its director.
He knew Berkeley was struggling to
make its calutrons work.
He saw that his thermal-diffusion process might
come to the bomb project’s rescue and he was generous enough and worried
enough about the war to offer it despite the Army’s several previous rebuffs.
He chose not to work through the limited official channels that the Army
and the OSRD had devised to constrict the flow of information.
“I wanted to
let Oppenheimer know what we were doing.
Someone in the Bureau of
Ships knew one of the people in the [Navy] Bureau of Ordnance who was
going out to Los Alamos.
I remember that I met the man at the old Warner
eater here in Washington, up in the balcony—real cloak and dagger
stuff.
”2093 Abelson briefed the BuOrd officer about the plant he was building.
He said that he expected to be producing 5 grams a day of material enriched
to 5 percent U235 by July.
is vital information the BuOrd man carried to
Los Alamos and passed along to Edward Teller.
2094 Teller in turn briefed
Oppenheimer.
Oppenheimer apparently conspired then with Deke Parsons,
the Hill’s ranking Navy man, to concoct a cover story: that Parsons had
learned of the Abelson work on a visit to the Philadelphia Navy Yard.
With
the Navy thus protected, Oppenheimer on April 28 alerted Groves.
Oppenheimer had seen Abelson’s January 1943 report only a few months
previously, a year aer it was written.
He was not impressed.
Like his
colleagues Oppenheimer had considered only those processes that enriched
natural uranium all the way up to bomb grade, a requirement thermal
diffusion could not efficiently meet.
Now he realized that Abelson’s process
offered a valuable alternative, the alternative Abelson had proposed in his
report to help Chicago advance its pile work: slight enrichment of larger
quantities.
Feeding even slightly enriched material into the Oak Ridge
calutrons would greatly increase their efficiency.
A thermal-diffusion plant
could therefore substitute at least temporarily for the stalled lower stages of
the K-25 plant and supplement the output of the Alpha calutrons.
Abelson’s
100-column plant with the columns operating in parallel, Oppenheimer
calculated, should produce about 12 kilograms a day of uranium of 1
percent enrichment.
“Dr.
Oppenheimer...
suddenly told me that we had [made] a terrible
scientific blunder,” Groves testified aer the war.
2095 “I think he was right.
It
is one of the things that I regret the most in the whole course of the
operation.
We had failed to consider [thermal diffusion] as a portion of the
process as a whole.” From the beginning the leaders of the Manhattan
Project had thought of the several enrichment and separation processes as
competing horses in a race.
at had blinded them to the possibility of
harnessing the processes together.
Groves had partly opened his eyes when
barrier troubles delayed K-25; then he had decided to cancel the upper
stages of the K-25 cascade and feed the lower-stage product to the Beta
calutrons for final enrichment.
So he was prepared to understand
immediately Oppenheimer’s similar point about the value of a thermal-
diffusion plant: “I at once decided that the idea was well worth
investigating.” 2096
Groves appointed a committee of men thoroughly experienced by now in
Manhattan Project troubleshooting: W.
K.
Lewis, Eger Murphree and
Richard Tolman.
ey visited the Philadelphia Navy Yard on June 1 and
turned in their conclusions on June 3.2097 ey thought Oppenheimer’s
estimate of 12 kilograms a day of 1 percent U235 optimistic but emphasized
the possibility—with 300 columns instead of 100—of producing 30
kilograms per day of 0.95 percent U235.
Groves thought bigger than that.
He had a power plant with 238,000
kilowatts rated capacity coming on line within weeks in the K-25 area at Oak
Ridge that K-25 would not be ready to draw on until the end of the year.
It
was designed to generate electricity to run the barrier diffusers but it made
electricity by making steam.
e steam could serve a thermal-diffusion plant
that would enrich uranium for the Alpha and Beta calutrons until such a
time as K-25 needed electricity.
en the permanent K-25 installation could
be phased in gradually and the temporary thermal-diffusion plant phased
out.
e proposal cleared the Military Policy Committee on June 12, 1944.
On
June 18 Groves contracted with the engineering firm of H.
K.
Ferguson to
build a 2,100-column thermal-diffusion plant beside the power plant on the
Clinch River in ninety days or less.
at extraordinary deadline allowed no
time for design.
Ferguson would assemble the operation from twenty-one
identical copies—“Chinese copies,” Groves called them—of Philip Abelson’s
100-column unit in the Philadelphia Navy Yard.
2098
e general must have appreciated the fortuity of his decision when he
learned the following month of the plutonium crisis at Los Alamos.
But the
thermal-diffusion plant was not immediately Oak Ridge’s savior.
Ferguson
managed to build a capacious 500-foot barn of black metal siding and began
operating the first rack of columns in sixty-nine days, by September 16, but
steam leaked out almost as fast as it could be blown in and couplings needed
extensive repair and even partial redesign.
e gaseousdiffusion plant, K-25,
was more than half completed but no barrier tubes shipped from Houdaille-
Hershey yet met even minimum standards.
e Alpha calutrons smeared
uranium all over the insides of their vacuum tanks, catching no more than 4
percent of the U235; that valuable fraction, reprocessed and fed into the
Beta calutrons, reached the Beta collectors in turn at only 5 percent
efficiency.
Five percent of 4 percent is two thousandths.
A speck of U235
stuck to an operator’s coveralls was well worth searching out with a Geiger
counter and retrieving delicately with tweezers.
No essence was ever
expressed more expensively from the substance of the world with the
possible exception of the human soul.
* * *
In the Pacific the island war advanced.
As the Army under General Douglas
MacArthur pushed up from Australia across New Guinea toward the
Philippines, the Marines under Admiral Chester Nimitz island-hopped from
Guadalcanal to Bougainville in the Solomons, north across the equator to
Tarawa in the Gilberts, farther north to Kwajalein and Eniwetok in the
Marshalls.
at brought them, by the summer of 1944, within striking
distance of the Japanese inner defense perimeter to the west.
Its nearest
bastions were the Marianas, a chain of volcanic islands at the right corner of
a roughly equilateral triangle of which the Philippine main island of Luzon
was the le corner and the Japanese main island of Honshu the apex.
e
United States wanted the Marianas as primary bases for further advance:
Guam for the Navy; Saipan and Tinian for the new B-29 Superfortresses that
the Army Air Force had begun deploying temporarily at great risk and
expense in China’s Szechwan province, ferrying aviation fuel and bombs
over the Himalayas to support their mission, which was the high-altitude
precision bombing of Japan.
By contrast, only fieen hundred miles of open
water separated Saipan and Tinian from Tokyo and the islands could be
supplied securely by sea.
Nimitz named the Marianas campaign Operation Forager; it began in
mid-June with heavy bombing of the island airfields.
en 535 ships
carrying 127,571 troops sailed from Eniwetok, the largest force of men and
ships yet assembled for a Pacific naval operation.
“We are through with flat
atolls now,” Holland Smith, the Marine commanding general, briefed his
officers.
“We learned to pulverize atolls, but now we are up against
mountains and caves where Japs can dig in.
A week from now there will be a
lot of dead Marines.
”2099
Intelligence estimates put 15,000 to 17,000 Japanese troops on Saipan,
10,000 on smaller Tinian three miles to the south.
e marines invaded
Saipan first, on the morning of June 15, and won a long but shallow
beachhead onto which, by aernoon, amphtracs had delivered 20,000 men.
Time correspondent Robert Sherrod was among them dodging shells from
Japanese artillery inland; he had seen action before on the Aleutian island of
Attu and on Tarawa and knew the Japanese as America had come to know
them:
Nowhere have I seen the nature of the Jap better illustrated than it was
near the airstrip at dusk.
I had been digging a foxhole for the night when
one man shouted: “ere is a Jap under those logs!” e command post
security officer was dubious, but he handed concussion grenades to a man
and told him to blast the Jap out.
en a sharp ping of the Jap bullet
whistled out of the hole and from under the logs a skinny little fellow—
not much over 5 .
tall—jumped out waving a bayonet.2100
An American tossed a grenade and it knocked the Jap down.
He
struggled up, pointed his bayonet into his stomach and tried to cut
himself open in approved hara-kiri fashion.
e disemboweling never
came off.
Someone shot the Jap with a carbine.
But, like all Japs, he took a
lot of killing.
Even aer four bullets had thudded into his body he rose to
one knee.
en the American shot him through the head and the Jap was
dead.
While the marines advanced into Saipan, fighting off the harrowing Japanese
frontal assaults they learned to call banzai charges, 155-millimeter Long
Toms brought ashore and set up in the southern sector of the island began
soening up Tinian.2101 at smaller island of thirty-eight square miles, ten
miles long and shaped much like Manhattan, was far less rugged than
Saipan.
Its highest elevation, Mount Lasso, rose only 564 feet above sea level;
its lowlands were planted in sugar cane; it had roads and a railway to
recommend it to tank operations.
To the disadvantage of amphibious assault
the island was a raised platform protected on all sides by steep cliffs 500 to
600 feet high—e Rock, the marines would come to call it.
It had two
major beaches, one near Tinian Town on the southwest coast and the other,
which the marines named Yellow, on the east coast at the island’s waist.
Navy
frogmen explored both by night and found them heavily mined and
defended.
Two other smaller beaches on the northwest coast hardly deserved the
name; one was 60 yards long and the other 150 yards.
e United States had
made no division-strength landing across any beach less than twice the
length of those two toeholds combined in the entire course of the war.
e
Japanese on Tinian accordingly defended them with nothing more than a
few mines and two 25-man blockhouses.
e marines coded them White 1
and White 2 and chose them for their assault.
e invasion of Tinian began on July 24, two weeks aer Saipan had been
secured.
Because of the larger island’s proximity the marines could deploy
shore-to-shore rather than ship-to-shore, embarking in LST’s and smaller
cra directly from Saipan.
A feint at Tinian Town beach decoyed the
Japanese defenses and the invaders achieved complete tactical surprise,
rushing ashore and pushing inland as fast as possible to escape the
dangerously narrow landings.
By the end of the day, when the advance
halted to organize a solid defense against the Japanese troops rushing up the
island from Tinian Town, most of the tanks had been brought ashore, four
howitzer batteries were in place and a spare battalion was even at hand.
e
defenders had killed fieen marines and wounded fewer than two hundred;
the American perimeter extended inland more than two miles.
With the coming of darkness the Japanese began a mortar barrage.
Near
midnight their artillery arrived and they added it in.
e marines answered
with their howitzers.
To watch for the expected Japanese counterattack they
illuminated the area with flares.
e attack started at 0300 hours, Japanese
soldiers rushing the American lines head-on in the naked light of the flares.
Against strong Marine defenses challenge quickly became slaughter.
e marines needed only four days to advance down the island.
ey
encountered tanks and infantry and in the mild terrain easily destroyed
them.
ey took Tinian Town on July 31, that night shattered a last banzai
charge from the south and the next day, August 1, 1944, declared the island
secure.
More than 6,000 Japanese combatants died compared to 300
Americans.
Another 1,500 marines were wounded.
Soon the Seabees would
arrive to begin bulldozing airfields.
Saipan before had been bloodier: 13,000 U.S.
casualties, 3,000 marines
killed, 30,000 Japanese defenders dead.
But a more grotesque slaughter had
engulfed the island’s population of civilians.
Believing as propaganda had
prepared them that the Americans would visit upon them rape, torture,
castration and murder, 22,000 Japanese civilians had made their way to two
sea cliffs 80 and 1,000 feet high above jagged rocks and, despite appeals from
Japanese-speaking American interpreters and even fellow islanders, had
flung themselves, whole families at a time, to their deaths.
e surf ran red
with their blood; so many broken bodies floated in the water that Navy cra
overrode them to rescue.
Not all the dead had volunteered their sacrifice;
many had been rallied, pushed or shot by Japanese soldiers.
e mass suicide on Saipan—a Jonestown of its day—instructed
Americans further in the nature of the Jap.
Not only soldiers but also
civilians, ordinary men and women and children, chose death before
surrender.
On their home islands the Japanese were 100 million strong, and
they would take a lot of killing.
* * *
“e view was stupendous, and the wind was bitter cold,” Leona Marshall
recalls of a day at Hanford, Washington, in September 1944 when she,
Enrico Fermi and Crawford Greenewalt climbed giddily to the top of a
twelve-story tower to survey the secret reservation.2102 ey could see the
Columbia River running deep and blue in both directions out of sight over
the horizon; they could see the gray desert and the distant hazy mountains.
By then construction was more than two-thirds completed and nearer at
hand they overlooked a city of industrial buildings and barracks and three
massive blockhouses, the three plutonium production reactors sited on the
river’s western shore.
e number of construction workers had peaked at
42,400 the previous June.
Marshall was working now at Hanford; Fermi and
Greenewalt had traveled out to monitor the start-up of the B pile, the first
one finished.
e day the construction teams le it, September 13, Fermi
had inserted the first aluminum-canned uranium slug to begin the loading,
the Pope conferring his blessing as he had on the piles at Chicago and Oak
Ridge.
Slug canning had almost come to a crisis.
Two years of trial-and-error
effort had not produced canning technology adequate to seal the uranium
slugs, which quickly oxidized upon exposure to air or water, away from
corrosion.
Only in August had the crucial step been devised, by a young
research chemist who had followed the problem from Du Pont in
Wilmington to Chicago and then to Hanford: putting aside elaborate dips
and baths he tried soaking the bare slugs in molten solder, lowering the
aluminum cans into the solder with tongs and canning the slugs submerged.
e melting point of the aluminum was not much higher than the melting
point of the solder, but with careful temperature control the canning
technique worked.
Greenewalt then pushed production around the clock.
Slugs accumulated
in the reactor building faster than the loading crews could use them and
Marshall and Fermi observed them there on one of their inspections:
Enrico and I went to the reactor building...
to watch the loading.
e
slugs were brought to the floor in solid wooden blocks in which holes
were drilled, each of a size to contain a slug, and the wooden blocks were
stacked much as had been the slug-containing graphite bricks in CP-1.
Idly I teased Fermi saying it looked like a chain-reacting pile.
Fermi
turned white, gasped, and reached for his slide rule.
But aer a couple of
seconds he relaxed, realizing that under no circumstances could natural
uranium and natural wood in any configuration cause a chain
reaction.2103
Tuesday evening, September 26, 1944, the largest atomic pile yet
assembled on earth was ready.
It had reached dry criticality—the smaller
loading at which it would have gone critical without cooling water if its
operators had not restrained it with control rods—the previous Friday.
Now
the Columbia circulated through its 1,500 loaded aluminum tubes.
“We
arrived in the control room as the du Pont brass began to assemble,”
Marshall remembers.2104 “e operators were all in place, well-rehearsed,
with their start-up manuals on their desks.” Some of the observers had
celebrated with good whiskey; their exhalations braced the air.
Marshall and
Fermi strolled the room checking readings.
e operators withdrew the
control rods in stages just as Fermi had once directed for CP-1; once again
he calculated the neutron flux on his six-inch slide rule.
Gradually gauges
showed the cooling water warmed, flowing in at 50°F and out at 140° “And
there it was, the first plutonium-production reactor operating smoothly and
steadily and quietly....
Even in the control room one could hear the steady
roaring sound of the high-pressure water rushing through the cooling
tubes.”
e pile went critical a few minutes past midnight; by 2 A.M.
it was
operating at a higher level of power than any previous chain reaction.
For
the space of an hour all was well.
en Marshall remembers the operating
engineers whispering to each other, adjusting control rods, whispering more
urgently.
“Something was wrong.
e pile reactivity was steadily decreasing
with time; the control rods had to be withdrawn continuously from the pile
to hold it at 100 megawatts.
e time came when the rods were completely
withdrawn.
e reactor power began to drop, down and down.
”2105
Early Wednesday evening B pile died.
Marshall and Fermi had slept by
then and returned.
2106 ey talked over the mystery with the engineers, who
first suspected a leaking tube or boron in the river water somehow plating
out on the cladding.
Fermi chose to remain open-minded.
e charts, which
seemed to show a straight-line failure, might be hiding the shallow curve of
an exponential decline in reactivity, which would mean a fission product
undetected in previous piles was poisoning the reaction.
Early ursday morning the pile came back to life.
By 7 A.M.
it was
running well above critical again.
But twelve hours later it began another
decline.
Princeton theoretician John A.
Wheeler had counseled Crawford
Greenewalt on pile physics since Du Pont first joined the project.
He was
stationed at Hanford now and he followed the second failure of the pile
closely.
He had been “concerned for months,” he writes, “about fission
product poisons.” B pile’s heavy breathing convinced him such a poisoning
had occurred.
e mechanism would be compound: “A non-
[neutron-]absorbing mother fission product of some hours’ half-life decays
to a daughter dangerous to neutrons.
is poison itself decays with a half-
life of some hours into a third nuclear species, non-absorbing and possibly
even stable.” 2107 So the pile would chain-react, making the mother product;
the mother product would decay to the daughter; as the volume of daughter
product increased, absorbing neutrons, the pile would decline; when
sufficient daughter product was present, enough neutrons would be
absorbed to starve the chain reaction and the pile would shut down.
en
the daughter product would decay to a non-absorbing third element; as it
decayed the pile would stir; eventually too little daughter product would
remain to inhibit the chain reaction and the pile would go critical again.
Fermi had le for the night; Wheeler on watch calculated the likely half-
lives based on the blooming and fading of the pile.
By morning he thought
he needed two radioactivities with half-lives totaling about fieen hours:
If this explanation made sense, then an inspection of the chart of nuclei
showed that the mother had to be 6.68 hr [iodine]135 and the daughter
9.13 hr [xenon]135.
Within an hour Fermi arrived with detailed reactivity
data which checked this assignment.
Within three hours two additional
conclusions were clear.
(a) e cross section for absorption of thermal
neutrons by Xe135 was roughly 150 times that of the most absorptive
nucleus previously known, [cadmium]113.
(b) Almost every Xe135 nucleus
formed in a high flux reactor would take a neutron out of circulation.
Xenon had thrust itself in as an unexpected and unwanted extra control
rod.
To override this poison more reactivity was needed.
2108
Greenewalt called Samuel Allison in Chicago on Friday aernoon.
Allison
passed the bad news to Walter Zinn at Argonne, the laboratory in the forest
south of Chicago where CP-1 was meant to be housed and where several
piles now operated.
Zinn had just shut down CP-3, a shielded sixfoot tank
filled with 6.5 tons of heavy water in which 121 aluminum-clad uranium
rods were suspended.
Disbelieving, Zinn started the 300-kilowatt reactor up
again and ran it at full power for twelve hours.
It was primarily a research
instrument and it had never been run so long at full power before.
He found
the xenon effect.
Laborious calculations at Hanford over the next three days
confirmed it.
Groves received the news acidly.
He had ordered Compton to run CP-3 at
full power full time to look for just such trouble.
Ever the optimist,
Compton apologized in the name of pure science: the mistake was
regrettable but it had led to “a fundamentally new discovery regarding
neutron properties of matter.” 2109 He meant xenon’s consuming appetite for neutrons.
Groves would have preferred to blaze trails less flamboyantly.
If Du Pont had built the Hanford production reactors to Eugene Wigner’s
original specifications, which were elegantly economical, all three piles
would have required complete rebuilding now.
Fortunately Wheeler had
fretted about fission-product poisoning.
Aer the massive wooden shield
blocks that formed the front and rear faces of the piles had been pressed, a
year previously, he had advised the chemical company to increase the count
of uranium channels for a margin of safety.
Wigner’s 1,500 channels were
arranged cylindrically; the corners of the cubical graphite stacks could
accommodate another 504.
at necessitated drilling out the shield blocks,
which delayed construction and added millions to the cost.
Du Pont had
accepted the delay and drilled the extra channels.
ey were in place now
when they were needed, although not yet connected to the water supply.
D pile went critical with a full 2,004-tube loading on December 17, 1944;
B pile followed on December 28.
Plutonium production in quantity had
finally begun.
Groves was enthusiastic enough at year’s end to report to
George Marshall that he expected to have eighteen 5-kilogram plutonium
bombs on hand in the second half of 1945.2110 “Looks like a race,” Conant
noted for his history file on January 6, 1945, “to see whether a fat man or a
thin man will be dropped first and whether the month will be July, August
or September.” 2111
17
The Evils of This Time
e bombs James Bryant Conant speculated about early in 1945 were crude
designs of uncertain yield.
e previous October he had traveled out to Los
Alamos to ascertain their prospects.
To Vannevar Bush he reported that the
gun method of detonation seemed “as nearly certain as any untried new
procedure can be.” 2112 e availability of a uranium gun bomb, which Los
Alamos expected would explode with a force equivalent to about 10,000 tons
of TNT, now depended only on the separation of sufficient U235.
Implosion
looked far more questionable; intensive work was just then getting under
way following Oppenheimer’s August reorganization of the laboratory.
Conant estimated the yield of the first implosion design, whether lensed or
not, “as an order of magnitude only” at about 1,000 tons TNT equivalent.
at was so relatively modest a result that he invited Bush to consider the
gun bomb strategic and the implosion bomb tactical.
For the past three years Bush and Conant had concentrated their efforts
entirely on these first crude bombs.
Now they were interested in
improvements.
During the summer of 1944, Conant says, on an earlier
inspection trip to Los Alamos, he and Bush had found leisure and privacy to
discuss “what the policy of the United States should be aer the war was
over.
”2113 As a result they had sent Secretary of War Henry L.
Stimson a joint
memorandum on September 19 that independently raised some of the issues
Niels Bohr had raised with Franklin Roosevelt in August, in particular that
“the progress of this art and science is bound to be so rapid in the next five
years in some countries that it would be extremely dangerous for this
government to assume that by holding secret its present knowledge we
should be secure.
”2114, 2115 ey did not see the bomb’s complementarity, but did see that whatever control arrangement the United States and Great
Britain devised—they favored a treaty—would somehow have to include the
Soviet Union; if the Soviets were not informed, as Bush told Conant, the
exclusion would lead “to a very undesirable relationship indeed on the
subject with Russia.” 2116
Roosevelt had returned from Hyde Park troubled that Felix Frankfurter
and Bohr had somehow breached Manhattan Project security, Bush and
perhaps Conant had talked to Bohr and the two administrators had
submitted to Stimson at his request a more detailed proposal incorporating
Bohr’s ideas.
In doing so they had explicitly recommended that the United
States sacrifice some portion of its national sovereignty in exchange for
effective international control, understanding as they did so that they would
have to answer vigorous opposition:
In order to meet the unique situation created by the development of this new art we would propose
that free interchange of all scientific information on this subject be established under the auspices
of an international office deriving its power from whatever association of nations is developed at
the close of the present war.
We would propose further that as soon as practical the technical staff
of this office be given free access in all countries not only to the scientific laboratories where such
work is contained, but to the military establishments as well.
We recognize that there will be great
resistance to this measure, but believe the hazards to the future of the world are sufficiently great to
warrant this attempt.2117
But how great in fact were the hazards?
at was something else Conant
traveled to Los Alamos in October to find out.
If the argument for allowing
the nation’s military establishments to be inspected depended on the
dangers of a thermonuclear explosive, it was speculative and therefore weak:
the thermonuclear was still only an idea on paper that might not work.
How
much could fission weapons be improved?
How much destructiveness of
either kind might a bomber—or, as Bush and Conant briefed Stimson, “a
robot plane or guided missile”—eventually visit upon the cities of the world?
2118
What Conant learned first of all was that others had already begun to ask
the same questions.
e technological imperative, the urge to improvement
even if the objects to be improved are weapons of mass destruction, was
already operating at Los Alamos.
Under intense pressure to produce a first
crude weapon in time to affect the outcome of the war, people had found
occasion nevertheless to think about building a better bomb.
Conant
reported to Bush:
By various methods that seem quite possible of development within six months aer the first bomb
is perfected, it should be possible to increase the efficiency...
in which case the same amount of
material would yield something like 24,000 Tons TNT equivalent.
Further developments along this
same line hold a possibility of producing a single bomb with such amounts of materials and such
efficiencies as to run this figure up to several hundred thousand Tons TNT equivalent, or even
perhaps a million Tons TNT equivalent....
All these possibilities reside only in perfecting the efficiency of the use of elements “25”[U235] and “49” [Pu239].
You will thus see that a
considerable “super” bomb is in the offing quite apart from the use of other nuclear reactions.
2119
A million tons TNT equivalent was devastation indeed—the world war
then raging would consume a total of about three million tons of explosives
by its end—but Edward Teller, Conant found, had already dismissed such
improvements as picayune:
It seems that the possibility of inciting a thermonuclear reaction involving heavy hydrogen is
somewhat less now than appeared at first sight two years ago.
I heard an hour’s talk on this subject
by the leading theoretical man at L.A.
e most hopeful procedure is to use tritium (the
radioactive isotope of hydrogen made in a pile) as a sort of booster in the reaction, the fission bomb being used as the detonator and the reaction involving the atoms of liquid deuterium being
the prime explosive.
Such a gadget should produce an explosive equivalent to 100,000,000 Tons of
TNT, which in turn should produce Class B damage over an area of 3,000 square miles!
is last real super bomb is probably at least as distant now as was the fission bomb when you
and I first heard of the enterprise.
e thermonuclear was something of a Rorschach test.
If it could be made to
work at all it was, like a fire, potentially unlimited; to build it larger you only
piled on more heavy hydrogen.
As Los Alamos paid less attention to Teller’s
Super his projection of its destructive potential grew moregrandiose.
Robert Oppenheimer also commited himself at that time to exploring the
thermonuclear—aer the war was won—in a letter to Richard Tolman on
September 20, 1944.
“I should like,” he emphasized, “...
to put in writing at
an early date the recommendation that the subject of initiating violent
thermonuclear reactions be pursued with vigor and diligence, and
promptly.” A way station on the road to a full-scale thermonuclear might be
a boosted fission bomb with a small charge of heavy hydrogen confined
possibly within the core of an implosion device:
In this connection I should like to point out that [fission] gadgets of reasonable efficiency and suitable design can almost certainly induct significant thermonuclear reactions in deuterium even
under conditions where these reactions are not self-sustaining....
It is not at all clear whether we
shall actually make this development during the present project, but it is of great importance that
such...
gadgets form an experimentally possible transition from a simple gadget to the super and
thus open the possibility of a not purely theoretical approach to the latter.
2120
(In fact not deuterium but tritium proved to be the necessary ingredient of a
boosted fission bomb, and such weapons were not developed until long aer
the end of the war.)
Alluding then to the larger consequences that Bohr had revealed,
Oppenheimer emphasized once more the urgency he attached to the pursuit
of an H-bomb: “In general, not only for the scientific but also for the
political evaluation of the possibilities of our project, the critical, prompt,
and effective exploration of the extent to which energy can be released by
thermonuclear reactions is clearly of profound importance.”
Working against the clock to build weapons that might end a long and
bloody war strained life at Los Alamos but also heightened it.
2121 “I always
pitied our Army doctors for their thankless job,” comments Laura Fermi:2122
ey had prepared for the emergencies of the battlefields, and they were faced instead with a high-
strung bunch of men, women, and children.
Highstrung because altitude affected us, because our
men worked long hours under unrelenting pressure; high-strung because we were too many of a
kind, too close to one another, too unavoidable even during relaxation hours, and we were all [as
Groves had warned his officers not entirely tongue-in-cheek] crackpots; high-strung because we
felt powerless under strange circumstances, irked by minor annoyances that we blamed on the
Army and that drove us to unreasonable and pointless rebellion.
ey made the best of it.
Mici Teller waged pointed rebellion saving the
backyard trees to preserve a playground for her son.
“I told the soldier in his
big plow to leave me please the trees here,” one of her friends remembers her
recounting, “so Paul could have shade but he said, ‘I got orders to level off
everything so we can plant it,’ which made no sense as it was planted by wild
nature and suits me better than dust.
e soldier le, but was back next day
and insisted he had more orders ‘to finish this neck of the woods.’ So I called
all the ladies to the danger and we put chairs under the trees and sat on
them.
2123 So what could he do?
He shook his head and went away and has
not come again.” Contrariwise, to clear a ski area on the hill to the west of
the mesa, George Kistiakowsky wrapped the trees with half-necklaces of
plastic explosive and thus noisily but efficiently cut them down.
“en we
scrounged equipment to build a rope tow and it became a nice little ski
slope,” he recalls.
2124
e Fermis moved to Los Alamos in September 1944 and requested one of
the less coveted fourplex apartments rather than the Ranch School faculty
cottage that had been prepared for them, to make a point about social
snobbery.
e Peierls, Rudolf and energetic Genia—Otto Frisch’s dish-
drying coach in Birmingham—lived below.
e mix of birthplaces and
citizenships was typical of the Hill: Peierls a German Jew, his wife a Russian,
both with British citizenship; Laura Fermi still nostalgic for Rome but she
and her husband new American citizens as of July.
“Oppie has whistled,”
Fermi would announce with a yawn when the morning siren sounded.
“It is
time to get up.” 2125 e Italian laureate directed a new operation, F (for
Fermi) Division, a catchall designed to take advantage of his versatility as
both theoretician and experimentalist.
One of the groups he caught was
Teller’s.
“at young man has imagination,” the forty-three-year-old Italian
emigré told his wife drolly of the thirty-six-year-old Hungarian.
“Should he
take full advantage of his inventiveness, he will go a long way.
”2126 Teller
stayed up late at night working out ideas and playing the piano and hardly
ever appeared in the Tech Area before late morning.
“Parties,” remembers Fuze Development group leader Robert Brode’s
articulate wife Bernice, “both big and brassy and small and cheerful, were an
integral part of mesa life.
It was a poor Saturday night that some large affair
was not scheduled, and there were usually several of them....
On [Saturday
nights] we raised whoopie, on Sundays we took trips, the rest of the week we
worked.” 2127 Single men and women sponsored dorm parties fueled with
tanks of punch made potent with mixed liquors and pure Tech Area grain
alcohol and invited wall-to-wall crowds.
e singles removed all the
furniture from their dormitory common rooms to make areas for dancing
and by unwritten rule kept their upstairs doors open through the night.
Square dancing evolved as a natural Saturday evening activity in that
Southwestern setting.
(“Everybody was wearing Western clothes—jeans,
boots, parkas,” Stanislaw Ulam’s French wife Françoise remembers noticing
with surprise when she and her husband arrived on the Hill.
“ere was a
feeling of mountain resort, in addition to army camp.
”2128) e dances were
first held in Deke Parsons’ living room, then the theater, then Fuller Lodge,
finally expanding to crowd the large mess hall.
Eventually even the Fermis
attended with their daughter Nella to learn the vigorous reels.
Long aer
mother and daughter had been persuaded from the sidelines Fermi sat
unbudging, mentally working out the steps.
When he was ready he asked
Bernice Brode, one of the leaders, to be his partner.
“He offered to be head
couple, which I thought most unwise for his first venture, but I couldn’t do
anything about it and the music began.
He led me out on the exact beat,
knew exactly each move to make and when.
He never made a mistake, then
or thereaer, but I wouldn’t say he enjoyed himself....
He [danced] with his
brains instead of his feet.
”2129
eater sometimes supplied a Saturday alternative.
At a performance of
Arsenic and Old Lace Robert Oppenheimer surprised and delighted the
audience by appearing powdered sepulchrally white with flour as the first of
the crowd of corpses emerging from the cellar in the last act.
Donald
Flanders, tall and bearded, known as Moll, Computation group leader in the
eoretical Division, wrote a comic ballet, Sacre du Mesa, set to George
Gershwin music.
Despite his beard and his lack of ballet training Flanders
danced the part of General Groves.
Samuel Allison’s son Keith appeared as
Oppenheimer, dancing on a large table wearing suitably casual clothes and a
pork-pie hat.
“e main stage prop,” Bernice Brode notes, “was a mechanical
brain with flashing lights and noisy bangs and sputters, which did
consistently wrong calculations, for example, 2 + 2 = 5.
In the grand but
hectic finale, the wrong calculations were revealed as the real sacred mystery
of the mesa.” 2130
Kistiakowsky preferred less formally intellectual entertainment:
I played a lot of poker with important people like Johnny Von Neumann, Stan Ulam, etc....
When
I came to Los Alamos I discovered that these people didn’t know how to play poker and offered to
teach them.
At the end of the evening they got annoyed occasionally when we added up the chips.
I used to point out that if they had tried to learn violin playing, it would cost them even more per
hour.
Unfortunately, before the end of the war, these great theoretical minds caught on to poker
and the evening’s accounts became less attractive from my point of view.2131
And Robert Wilson, Cyclotron Program group leader, who served on the
advisory Town Council, discovered even more elemental activities on the
Hill despite security screening before employment and roving military
police:
Of the many problems that were presented to us during my term of office, the most memorable
was when the M.P.’s who guarded the site chose to place one of our women’s dorms off-limits.
ey
recommended that we close the dorm and dismiss the occupants.
A tearful group of young ladies
appeared before us to argue to the contrary.
Supporting them, a determined group of bachelors
argued even more persuasively against closing the dorm.
It seems that the girls had been doing a
flourishing business of requiting the basic needs of our young men, and at a price.
2132 All understandable to the army until disease reared its ugly head, hence their interference.
By the time
we got that matter straightened out—and we did decide to continue it—I was a considerably more
learned physicist than I had intended to be a few years earlier when going into physics was not all
that different from taking the cloth.
Married or single, the occupants of Post Office Box 1663 were young and
healthy; they produced so many babies that Groves ordered either the
reservation commander or the laboratory director—both versions of the
story survive—to staunch the flood.
Oppenheimer, if Oppenheimer it was,
refused the duty.
With justification: his wife Kitty bore him a second child, a
daughter, Katherine, called Toni, on December 7, 1944.
So many people
wanted to see the boss’s baby that the hospital identified the crib with a sign
and lines formed to file past the nursery window.
Crowded together behind a fence, Hill families worried about epidemic
disease.
A pet dog that had bitten several children turned up rabid and pet
owners debated angrily with parents about which category of dependent
should be kept on a leash.
More frightening was the sudden death of a young
chemist, a group leader’s wife, from an unidentified form of paralysis.
Fearing an outbreak of poliomyelitis, doctors closed the schools, put Santa
Fe off limits and ordered all children indoors.
No new cases appeared, the danger abated with the continuation of cold
weather and work and play resumed.
“I don’t think I shall ever again live in a
community where so many brains were,” comments Edwin McMillan’s wife
Elsie, Ernest Lawrence’s sister-in-law, “nor shall I ever live in a community
so confined that visitors expected us to fight with each other.
We didn’t have
telephones, we didn’t have the bright lights, but I don’t think I shall ever live
in a community that had such deep roots of cooperation and friendship.
”2133
Some reserved Sundays for church and hobbies; others devoted the day to
outings.
e Oppenheimers maintained magnificent riding horses and rode
regularly on Sunday morning but only once in three years found time for an
overnight excursion.
Kistiakowsky bought one of Oppenheimer’s quarter
horses and refreshed himself trailing in the mountains aer his late Saturday
poker nights; the Army stabled the private animals along with the remuda it
kept for the mounted MP’s who patrolled the mesa fences.
Emilio Segrè
found excellent fly-fishing.
“e streams are full of big trouts,” he announced
happily to newcomers.
“All you have to do is throw in a line and they bite
you, even if you are shouting.” 2134 Fermi took up angling, says Segrè, “but he
went about it in a peculiar way.
2135 He had tackle different from what
anyone else used for trout fishing, and he developed theories about the way
fish should behave.
When these were not substantiated by experiment, he
showed an obstinacy that would have been ruinous in science.” Fermi
insisted on fishing for trout with worms, arguing that the condemned
creatures should be offered an authentic final meal, not the dry flies of
tradition.
Segrè made a point of reviewing the subtleties of trout fishing with
his old friend.
“Oh, I see, Emilio,” Fermi eventually countered, “it is a battle
of wits.” 2136
Mountain climbing had long been a Hans Bethe hobby.
He and Fermi,
among others, sometimes scaled Lake Peak across the Rio Grande in the
Sangre de Cristos, one of Bethe’s admiring group leaders remembers, to “sit
there in the sunshine” at 12,500 feet “discussing physics problems.
is is
how many discoveries were made.
”2137 Leona Marshall, who moved with
Fermi to Los Alamos, recalls less Olympian hours with “nothing to do but
admire the view and gasp for breath.” 2138
Equally strenuous excursions went out to area landmarks.
Genia Peierls
and Bernice Brode determined to find the Stone Lions, prehistoric lifesized
twin effigies of crouching mountain lions carved in tuff, reported beside a
ruined pueblo on a distant mesa.
ey gathered up a carload of Navy
ensigns and another of young bachelors from the British mission and drove
within ten miles of their goal, then set out walking, Genia Peierls leading the
way in tennis shoes without socks: “Best for stones, best for bunions.” Lunch
at two in the aernoon by a cool canyon stream encouraged the weary
ensigns to drop anchor, but Mrs.
Peierls had cowed the young British
mission men from similar protest.
“OK, we proceed to Stone Lions without
U.
S.
Navy.
All aboard.” More hiking, crossing desert country from mesa to
mesa, the Rio Grande below.
e American woman was impressed with the
Stone Lions; not so the Russian.
“House cats only, my dear, not well made
and maybe not even old.” “On the way back,” Bernice Brode recalls, “the
young men...
looked out over the wide expanse of the desert region and
the ribbon of water shining in the setting sun.
One of them, dark and slim,
wearing tortoise shell rimmed glasses, spoke in his so voice with a slight
German accent.
‘I have not seen New York, nor Chicago, but I have seen the
Stone Lions.’ He smiled pleasantly as we walked on.
His name was Klaus
Fuchs.” Penny-in-the-slot Fuchs, Genia Peierls nicknamed him, because the
quiet, hardworking emigré theoretician only spoke when spoken to.2139
On a hike through Frijoles Canyon with the Fermis, Niels Bohr stopped to
admire a skunk, an animal unknown to Europeans, but it chose not to
instruct the vigorous Dane in the pungency of its defenses.
Bears sometimes
appeared on the trails, prompting warnings in the daily bulletin: “Remember
that these are not tame bears like those in Yellowstone Park.
”2140 A family cat
turned up with a suppurating jaw; the Hill’s Army veterinarian recognized
the bone necrosis as a sign of radiation poisoning from Tech Area
contamination and kept the animal alive to observe its unusual
symptomatology, about which not much was yet known.
Its tongue swelled
and its hair fell out in patches; its heartsick owner eventually asked that the
animal be destroyed.
A low-power radio station began broadcasting to Hill residents on
Christmas Eve, 1943, drawing on several fine collections of classical records,
including Oppenheimer’s; the few New Mexicans beyond the Hill who could
receive the station’s signals were puzzled that announcers never introduced
live performers by their last names.
e “Otto” who occasionally played
classical piano selections was Otto Frisch.
A golf course opened in June
1944.
Men and women fielded baseball, soball and basketball teams.
e
Army divided up the old Ranch School truck garden east of Fuller Lodge
into victory-gardening plots but had no water to spare for irrigation.
Life was rougher for construction workers, machinists, soldiers and
WAC’s: minimal barracks, jerrybuilt dormitories, muddy trailer courts.
Hillbilly construction families invited once in the interest of authenticity to
the square dancing at the mess hall arrived drunk and nearly caused a riot;
thereaer a man in uniform guarded the door.
Hans Bethe recalls that one
wild machinist late in the war, when the laboratory took what help it could
find, slit a fellow worker’s throat “from cover to cover.
”2141 e Indians from
San Ildefonso and other pueblos and ranches in the area lived better for their
work on the Hill as cleaning women and maintenance men.
e hand-coiled
black pottery of Maria Martinez soon graced many Los Alamos apartments.
In winter a pall of coal smoke hung over the mesa.
e men the Army
assigned to service the apartment furnaces stoked them so hot that
apartment walls sometimes sizzled.
Los Alamos sat high and dry
surrounded by pine forests, and fire worried everyone.
e main machine
shop in the Tech Area caught fire one night early in 1945; Eleanor Jette
remembers watching her husband Eric, Metal Reduction group leader in the
Chemistry and Metallurgy Division, standing with Oppenheimer and the
Hill commanding officer on the fire escape of the administration building
grimly overseeing the firefighters.
“Jesus,” she heard someone say, “let’s be
thankful it isn’t D building.
at place is as hot as seven million dollars.
Every time it gets too hot for them to work, they slap on another coat of
paint.” Her husband worked in D building; she did not know he worked with
plutonium but understood that “hot” meant radioactive.
“Damn,” he told
her when she asked.
“You mustn’t be upset.
We’re so careful it’s fantastic.” 2142
A fire in the plutonium-handling areas would be a major disaster; aer the
machine-shop fire Groves ordered a fireproof plutonium works built with
steel walls and a steel roof and filtering systems for both incoming and
outgoing air.
Robert Oppenheimer oversaw all this activity with self-evident
competence and an outward composure that almost everyone came to
depend upon.
“Oppenheimer was probably the best lab director I have ever
seen,” Teller repeats, “because of the great mobility of his mind, because of
his successful effort to know about practically everything important
invented in the laboratory, and also because of his unusual psychological
insight into other people which, in the company of physicists, was very
much the exception.” 2143 “He knew and understood everything that went on
in the laboratory,” Bethe concurs, “whether it was chemistry or theoretical
physics or machine shop.
He could keep it all in his head and coordinate it.
It was clear also at Los Alamos that he was intellectually superior to us.” 2144
e eoretical Division leader elaborates:
He understood immediately when he heard anything, and fitted it into the general scheme of
things and drew the right conclusions.
ere was just nobody else in that laboratory who came
even close to him.
In his knowledge.
ere was human warmth as well.
Everybody certainly had
the impression that Oppenheimer cared what each particular person was doing.
In talking to
someone he made it clear that that person’s work was important for the success of the whole
project.
I don’t remember any occasion at Los Alamos in which he was nasty to any person,
whereas before and aer the war he was oen that way.
At Los Alamos he didn’t make anybody feel
inferior, not anybody.2145
Yet Oppenheimer felt inferior himself, had always felt for the actions of
his life, as he confessed many years aerward, “a very great sense of
revulsion and of wrong.” At Los Alamos for the first time he seems to have
found alleviation of that loathing.
He may have discovered there a process of
self-analysis anchored in complementarity that served him more
comprehensively later in his life: “In an attempt to break out and be a
reasonable man, I had to realize that my own worries about what I did were
valid and were important, but that they were not the whole story, that there
must be a complementary way of looking at them, because other people did
not see them as I did.2146 And I needed what they saw, and needed them.”
Certainly he found the more traditional alleviation of losing himself in
work.
Whatever his burden of morale and work in those years, Oppenheimer
also carried his full share of private pain.
He was kept under constant
surveillance, his movements monitored and his rooms and telephones
bugged; strangers observed his most intimate hours.
His home life cannot
have been happy.
Kitty Oppenheimer responded to the stress of living at
isolated Los Alamos by drinking heavily; eventually Martha Parsons, the
admiral’s daughter, took over the duties of social leadership on the Hill.
Army security officers hounded the director of the central laboratory of the
nation’s most important secret war project mercilessly; at least one of them,
Peer de Silva, was convinced Oppenheimer was a Soviet spy.
ey
interrogated him frequently, fishing for the names of people he knew or
believed to be members of the Communist Party, hoping to trip him up.
He
invented circumstances and volunteered the names of friends to protect his
own, indiscretions that would return in time to haunt him.2147
During the first Los Alamos summer he heard from Jean Tatlock, the
unhappy woman he had loved before he met his wife.
Loyally, even though
she had been and still might be a Communist and he knew himself to be
spied upon, he went to her; an FBI document coldly summarizes a security
man’s peepshow version of that meeting:
On June 14, 1943, Oppenheimer traveled via Key Railway from Berkeley to San Francisco on the
evening of June 14, 1943, where he was met by Jean Tatlock who kissed him.
ey dined at the
Xochimilcho Cafe, 787 Broadway, San Francisco, then proceeded at 10:50 P.M.
to 1405
Montgomery Street and entered a top floor apartment.
Subsequently, the lights were extinguished
and Oppenheimer was not observed until 8:30 A.M.
next day when he and Jean Tatlock le the
building together.
2148
In January 1944 Jean Tatlock committed suicide.
“I wanted to live and to
give and I got paralyzed somehow,” her suicide note said.2149 It was a
paralysis of the spirit Oppenheimer seemingly had to resist in himself.
Planning began in March 1944 for a full-scale test of an implosion
weapon.
Sometime between March and October Oppenheimer proposed a
code name for that test.
2150 e first man-made nuclear explosion would be
a historic event and its designation therefore a name that history might
remember.
Oppenheimer coded the test and the test site Trinity.
Groves
wrote him in 1962 to find out why, speculating that he chose the name
because it is common to rivers and peaks in the American West and would
be inconspicuous.
“I did suggest it,” Oppenheimer responded, “but not on [that]
ground....2151 Why I chose the name is not clear, but I know what thoughts
were in my mind.
ere is a poem of John Donne, written just before his
death, which I know and love.
From it a quotation:
As West and East
In all flatt Maps—and I am one—are one,
So death doth touch the Resurrection.”
e poem was Donne’s “Hymne to God My God, in My Sicknesse,” and
among its subtleties it construes a complementarity that parallels the
complementarity of the bomb that Bohr had recently revealed to
Oppenheimer.
(“Bohr was deeply in this,” Bethe testifies, “and this was his
real interest, and Bohr had long conversations with Oppenheimer which
brought Oppenheimer into this at a very early stage.
Oppenheimer was very
much indoctrinated by Bohr’s ideas of international control.
”2152) at dying
leads to death but might also lead to resurrection—as the bomb for Bohr
and Oppenheimer was a weapon of death that might also end war and
redeem mankind—is one way the poem expresses the paradox.
“at still does not make a Trinity,” Oppenheimer’s letter to Groves goes
on, “but in another, better known devotional poem Donne opens, ‘Batter my
heart, three person’d God;—.’ Beyond this, I have no clues whatever.” 2153 Nor
must Groves have had; but the fourteenth of Donne’s Holy Sonnets equally
explores the theme of a destruction that might also redeem:
Batter my heart, three person’d God; for you
As yet but knocke, breathe, shine, and seeke to mend;
at I may rise, and stand, o’erthrow mee, and bend
Your force to breake, blowe, burn and make me new.
I, like an usurpt towne, to another due,
Labour to admit you, but Oh, to no end;
Reason, your viceroy in mee, mee should defend,
But is captiv’d, and proves weake or untrue.
Yet dearly I love you, and would be loved faine,
But am betroth’d unto your enemie:
Divorce me, untie, or breake that knot againe,
Take mee to you, imprison me, for I
Except you enthrall me, never shall be free,
Nor ever chaste, except you ravish me.
at is poetry perhaps martial enough, ardent enough and sufficiently
fraught with paradox to supply a code name for the first secret test of a
millennial force newly visited upon the world.
Oppenheimer did not doubt that he would be remembered to some
degree, and reviled, as the man who led the work of bringing to mankind for
the first time in its history the means of its own destruction.2154 He
cherished the complementary compensation of knowing that the hard riddle
the bomb would pose had two answers, two outcomes, one of them
transcendent.
Such understanding justified the work at Los Alamos if
anything did, and the work in turn healed the split between self and
overweening conscience that hurt him.2155 He had long recognized the
possibility of such a convalescence and evoked it explicitly in the epistle on
discipline he wrote his brother Frank in 1932 that concluded in Pauline
measure: “erefore I think that all things which evoke discipline: study, and
our duties to men and to the commonwealth, war, and personal hardship,
and even the need for subsistence, ought to be greeted by us with profound
gratitude; for only through them can we attain to the least detachment; and
only so can we know peace.
”2156 At Los Alamos, if only for a time, he located
that detachment in duties to men and to the commonwealth that Bohr was
teaching him to believe might be worthy, not macabre.
He was not the first
man to find himself in war.
* * *
To develop implosion Los Alamos had to develop diagnostics, ways to see
and to measure events that began and ended in considerably less time than
the blink of an eye.
e iron pipes Seth Neddermeyer imploded could be
studied by aiming a high-speed flash camera down their bores, but how
could the physicists of G Division observe the shaping of a detonation wave
as it passed through solid blocks of high explosives, or the compression of
the metal sphere which those explosives completely surrounded?
ey were
competent research scientists who had been working within narrow
technological constraints for a year and a half; diagnostics demanded
imagination and they brought all their frustrated creativity to the task.
X-raying was a reliable approach; the Ordnance Division had already used
X rays to study the behavior of small spherical arrangements of explosives.
X
rays reveal differences in density—dense bone casts a darker shadow than
lighter flesh—and since the detonation wave of a developing implosion
changed the density of the explosive material as it burned its way through, X
rays could make that wave visible.
But adapting X-ray diagnostics to
implosion studies on an increasing scale meant protecting fragile X-ray
equipment from the repeated blasts of as much as two hundred pounds of
high explosives at a time.
at challenge the physicists met by the
unorthodox expedient of mounting their implosion tests between two
closely spaced blockhouses with the X-ray unit in one building and the
radiography equipment in the other, accessible to the test event through
protected ports.
Ultimately flash X-ray equipment—high-current X-ray
tubes that pulsed as rapidly as every ten-millionth of a second—proved most
useful for detonation-wave studies.
e behavior of a test unit’s HE shell was easier to study with X rays and
high-speed photography than was the compression of its denser metal core.
For following the metal core as it squeezed to less than half its previous
volume Los Alamos developed several different diagnostic methods and
used them in complement.
One method set the test unit within a magnetic field and measured
changes in field configuration as the metal sphere compressed.
Since HE is
essentially transparent to magnetism, this method allowed the physicists
eventually to study full-scale assemblies.
It gave reliable measure of shock
waves reflected from the core and of the troublesome detonation-wave
intersections that caused jets and spalling.
Carefully spaced prearranged wires contacted by the metal sphere as it
imploded supplied information not only about the timing of the implosion
but also about material velocities at various depths within the core.
at
provided direct, quantitative data which the eoretical Division could use
to check how well its hydrodynamic theory fit the facts.
e Electric Method
group began by measuring the high-explosive acceleration of flat metal
plates.
Early in 1945 it adapted its techniques to partial spheres and
eventually to spheres surrounded by HE lens systems with only one lens
removed to access the necessary wires.
Duplicated at another test site, the blockhouse arrangement that served to
protect ordinary X-ray equipment also served to shield the most unusual
diagnostic method the scientists devised: firing pulsed X rays from a
betatron through scale-model implosion units into a cloud chamber and
photographing the resulting ionization tracks with a stereoscopic camera.1
e betatron method needed an ingenious timing circuit to trigger in quick
but precise sequence the explosive charge, the betratron X-ray pulse, the
expansion of the diaphragm of the cloud chamber that made the ionization
tracks visible as droplets in the fog and the camera shutters that
photographed them.
e fih successful method G Division developed varied the betatron
method by incorporating an intense source of gamma radiation within the
core itself.
e source, radioactive lanthanum extracted from among fission
products of the Oak Ridge air-cooled pile, gave the method its name: RaLa.
Not a cloud chamber but alignments of rugged ionization chambers served
to register the changing patterns of radiation from the RaLa cores as they
compressed.
Since no one knew at first how extensively the radiolanthanum
would contaminate the test site, Luis Alvarez, who coordinated the first
experiment, borrowed two tanks from the Army’s Dugway Proving Ground
in Utah to use as temporary blockhouses.
He recalls spectacular results:
I was sitting in the tank when the first explosion went off.
George Kistiakowsky was in one tank
and I was in the other.
We were looking through the periscopes and all that happened was that it
blew a lot of dust in our eyes.
2157 And then—we hadn’t thought about this possibility at all—the whole forest around us caught on fire.
ese pieces of white-hot metal went flying off into the wild
blue yonder setting trees on fire.
We were almost surrounded.
Implosion lens development had begun the previous winter, says Bethe,
when John von Neumann “very quickly designed an arrangement which was
obviously correct from the theoretical point of view—I had tried and
failed.” 2158 Now in the fall and winter of 1944–45 Kistiakowsky had to make
the theoretical arrangement work.
An optical lens takes advantage of the fact that light travels at different
velocities in different media.
Light traveling through air slows when it
encounters glass.
If the glass curves convexly, as a magnifying glass is
curved, the light that encounters the thicker center must follow a longer
path than the light that encounters the thinner edges.
e effect of these
differing path lengths is to direct the light toward a focal point.
e implosion lens system von Neumann designed was made up of
truncated pyramidal blocks about the size of car batteries.
e assembled
lenses formed a sphere with their smaller ends pointing inward.
Each lens
consisted of two different explosive materials fitted together—a thick, fast-
burning outer layer and a shaped slow-burning solid inclusion that extended
to the surface of the face of the block that pointed toward the bomb core:
e fast-burning outer layer functioned for the detonation wave as air
around an optical lens functions for light.
e slower-burning shaped
inclusion functioned as a magnifying glass, directing and reshaping the
wave.
A detonator would ignite the fast-burning explosive.
at material
would develop a spherical detonation wave.
When the apex of the wave
advanced into the apex of the inclusion, however, it would begin burning
more slowly.
e delay would give the rest of the wave time to catch up.
As
the detonation wave encountered and burned through the inclusion it thus
reshaped itself from convex to concave, from a spherical wave expanding
from a point to a spherical wave converging on a point, emerging fitted to
the convex curve of the spherical tamper.
Before the reshaped wave reached
the tamper it passed through a second layer of solid blocks of fast-burning
explosive to add to its force.
e heavy natural-uranium tamper then served
to smooth out any minor irregularities as the spherical shock wave
compressed it passing through to the plutonium core.
Kistiakowsky would apologize aer the war for a research program “too
frequently reduced to guesswork and empirical shortcuts” because the field
had been grossly neglected.
2159 “Prior to this war the subject of explosives
attracted very little scientific interest,” he wrote in an introduction to a
technical history of X Division’s work, “these materials being looked upon as
blind destructive agents rather than precision instruments; the level of
fundamental knowledge concerning detonation waves—and strong shock
waves induced by them in the adjacent non-explosive media—was
distressingly low.
”2160 To support its experiments X Division expanded an
explosives-casting site a few miles south of Anchor Ranch, constructing
roughhewn earth-sheltered timber buildings because hauling in concrete
would have delayed the work.
Not until mid-December 1944 did a lens test look promising; the eighteen
5-kilogram bombs Groves told George Marshall he hoped to have on hand
by the second half of 1945 he also thought might explode so inefficiently
that each would be equivalent to no more than 500 tons of TNT, down from
the 1,000 tons Conant had heard estimated in October.
Kistiakowsky had to fight once more with Parsons before he won the field.
“So much pessimism was developing about our ability to build satisfactory
lenses,” he recalls, “that Captain Parsons began urging (and he was not alone
in this) that we give up lenses completely and try somehow to patch up the
non-lens type of implosion.
”2161 Kistiakowsky thought that alternative
hopeless.
Early in 1945 Groves came out to monitor the debate.
In the end
Oppenheimer took Kistiakowsky’s side and decided for lenses.
Parsons’
Ordnance Division then restricted its work to the uranium gun, Little Boy,
and to engineering the weapons for the battlefield.
X and G Divisions
worried about implosion.
Finishing the high-explosive castings by machining them was the most
dramatic innovation Kistiakowsky introduced.
He wanted to shape the HE
components entirely by machining from solid pre-cast blocks but lacked
sufficient time to develop and build the elaborate remote-controlled
machinery the innovative technology would have required.
He settled
instead for precision casting with machine finishing and used his limited
supply of machinists primarily to turn out the necessary molds.
Molds gave
him “the greatest agony,” he remembers; the HE components of the bomb
totaled “something in the nature of a hundred or so pieces, which had to fit
together to within a precision of a few thousandths of an inch on a total size
of five feet and make a sphere.
So we had to have very precise molds.” 2162
Eventually mold procurement paced Fat Man’s testing and delivery.
But even with the necessary molds on hand, casting HE was far from
simple, another technology that had to be learned by trial and error.
In
February 1945 Kistiakowsky chose an explosive called Composition B to
serve as the fast-burning component of Fat Man’s lenses and a mixture he
had commissioned from a Navy research laboratory, Baratol, for the slow-
burning component.
2163 Composition B was poured as a hot slurry of wax,
molten TNT and a non-melting crystalline powder, RDX, that was 40
percent more powerful than TNT alone.
Baratol slurried barium nitrate and
aluminum powder with TNT, stearoxyacetic acid and nitrocellulose:
We learned gradually that these large castings, fiy pounds and more each, had to be cooled in just
certain ways, otherwise you get air bubbles in the middle or separations of solids and liquids, all of
which screwed up the implosion completely.
So it was a slow process.
e explosive was poured in
and then people sat over that damned thing watching it as if it was an egg being hatched, changing
the temperature of the water running through the various cooling tubes built into the mold.
2164
e wilderness reverberated that winter to the sounds of explosions,
gradually increasing in intensity as the chemists and physicists applied small
lessons at larger scale.
“We were consuming daily,” says Kistiakowsky,
“something like a ton of high performance explosives, made into dozens of
experimental charges.
”2165 e total number of castings, counting only those
of quality sufficient to use, would come to more than 20,000.
X Division
managed more than 50,000 major machining operations on those castings in
1944 and 1945 without one explosive accident, vindication of Kistiakowsky’s
precision approach.
A RaLa test on February 7, 1945, showed definite
improvement in implosion symmetry.
On March 5, aer a strained round of
conferences, Oppenheimer froze lens design.
However scarce plutonium
might be, no one doubted that Fat Man would have to be tested at full scale
before a military weapon could be trusted to work.
* * *
A problem small in scale but difficult of solution was the initiator, the
minuscule innermost component of the bombs.2166 e chain reaction
required a neutron or two to start it off.
No one wanted to trust a billion
dollars’ worth of uranium or several hundred million dollars’ worth of
plutonium to spontaneous fission or a passing cosmic ray.
Neutron sources
had been familiar laboratory devices for more than a decade, ever since
James Chadwick bombarded beryllium with alpha particles from polonium
and broke the elusive neutral particle free in the first place.
In his early
lectures at Los Alamos Robert Serber had discussed using a radium-
beryllium source in a gun bomb with the radium attached to one piece of
core material and the beryllium to the other, arranged to smash together
when the gun was fired and the two core components mated to complete a
critical assembly.
Radium released dangerous quantities of gamma radiation,
however, and Edward Condon noted in the Los Alamos Primer that “some
other source such as polonium...
will probably prove more satisfactory.” 2167
Polonium emitted copious quantities of alpha particles energetic enough to
knock neutrons from beryllium but very little gamma radiation.
e challenge of initiator development was to design a source of sufficient
neutron intensity that released those neutrons only at the precise moment
they were needed to initiate the chain reaction.
In the case of the uranium
gun that requirement would be relatively easy to meet, since the alpha
source and the beryllium could be separated with the bullet and the target
core.
But the implosion bomb offered no such convenient arrangement for
separation and for mixing.
Polonium and beryllium had to be intimately
conjoined in Fat Man at the center of the plutonium core but inert as far as
neutrons were concerned until the fraction of a microsecond when the
imploding shock wave squeezed the plutonium to maximum density.
en
the two materials needed instantaneously to mix.
Polonium, element 84 on the periodic table, was a strange metal.
Marie
and Pierre Curie had isolated it by hand from pitchblende residues (at
backbreaking concentrations of a tenth of a milligram per ton of ore) in
1898 and named it in honor of Marie Curie’s native Poland.
Physically and
chemically it resembled bismuth, the next element down the periodic table,
except that it was a soer metal and emitted five thousand times as much
alpha radiation as an equivalent mass of radium, which caused the ionized,
excited air around a pure sample to glow with an unearthly blue light.
Po210, the isotope of polonium that interested Los Alamos, decayed to
lead 206 with the emission of an alpha particle and a half-life of 138.4 days.
e range of Po210’s alphas was some 38 millimeters in air but only a few
hundredths of a millimeter in solid metals; the alphas gave up their energies
ionizing atoms along the way and finally came to a stop.
at meant the
polonium for an initiator could be safely confined within a sandwich of
metal foils.
Sandwiching the foils in turn might be concentric shells of light,
silvery beryllium.
e entire unit need be no larger than a hazelnut.
“I think I probably had the first idea [for an initiator design],” Bethe
remembers, “and Fermi had a different idea, and I thought mine was better
for once, and then I was the chairman of a committee of three to watch the
development of the initiator.
”2168 Segregating the Po210 from the beryllium
was straightforward.
Making sure the two elements mixed thoroughly at the
right instant was not, and the primary difference between initiator designs—
many were invented and tested during the winter of 1944–45—was their
differing mixing mechanisms.
A quantity of Po210 equivalent in alpha
activity to 32 grams of radium, thoroughly mixed with beryllium, would
produce some 95 million neutrons per second, but that would be no more
than nine or ten neutrons in the brief ten-millionth of a second when they
would be useful in an imploding Fat Man to start the chain reaction;
therefore the mixing had to be certain and thorough.
Initiator design has
never been declassified, but irregularities machined into the beryllium outer
surface that induced turbulence in the imploding shock wave probably did
the job: the Fat Man initiator may have been dimpled like a golf ball.
To supply ten neutrons to initiate a chain reaction men labored for years.
Bertrand Goldschmidt, a French chemist who had once been Marie Curie’s
personal assistant and who came to the United States aer the invasion of
France to work with Glenn Seaborg at the Met Lab, extracted the first half-
curie of initiator polonium from old radon capsules at a New York cancer
hospital (polonium is a daughter product of radium decay).
Quantity
production required using scarce neutrons from the Oak Ridge air-cooled
pile to transmute bismuth one step up the periodic table to Po.
Charles A.
omas, research director for the Monsanto Chemical Company, a
consultant on chemistry and metallurgy, took responsibility for purifying
the Po, for which purpose he borrowed the indoor tennis court on his
mother-in-law’s large and securely isolated estate in Dayton, Ohio, and
converted it to a laboratory.
omas shipped the Po on platinum foil in sealed containers, but another
nasty characteristic of polonium caused shipping troubles: for reasons never
satisfactorily explained by experiment, the metal migrates from place to
place and can quickly contaminate large areas.
“is isotope has been
observed to migrate upstream against a current of air,” notes a postwar
British report on polonium, “and to translocate under conditions where it
would appear to be doing so of its own accord.” 2169 Chemists at Los Alamos
learned to look for it embedded in the walls of shipping containers when
omas’ foils came up short.
Initiator studies proceeded in G Division at a test site established in
Sandia Canyon, one mesa south of the Hill.
e Initiator group drilled blind
holes in large turbine ball bearings—screwballs, the experimenters called
them—inserted test initiators and plugged the holes with bolts.2170 Aer
imploding the screwballs they recovered the remains and examined them to
see how well the Po and Be had mixed.
Mixing, unfortunately, could not be a
conclusive measure of effectiveness.
Bethe’s committee selected the most
promising design on May 1, 1945, but only a full-scale test culminating in a
chain reaction could prove definitively that the design worked.
* * *
Progress toward a Japanese atomic bomb, never rapid, slowed to frustration
and futility across the middle years of the Pacific war.
Aer the Imperial
Navy had bowed out of atomic energy research Yoshio Nishina had
continued patriotically to pursue it even though he privately believed that
Japan in challenging the United States had invited certain disaster.2171 On
July 2, 1943, Nishina had met with his Army liaison, a Major General
Nobuuji, to report that he had “great expectations” for success.
2172 He noted
that the Air Force had asked him to study uranium as a possible aircra fuel,
as an explosive and as a source of power, and he had recently received a
request for assistance from another Army laboratory, which had contributed
2,000 yen to his expenses.
Nobuuji promptly discouraged such
consultations.
“e main point,” Nishina agreed, “is to complete the project
as rapidly as possible.” His calculations, he told Nobuuji, indicated that 10
kilograms of U235 of at least 50 percent purity should make a bomb,
although cyclotron experiments would be necessary to determine “whether
10 kg.
will be sufficient, or whether it will require 20 kg.
or even 50 kg.” He
wanted help finishing his 60-inch cyclotron:2173
e 250-ton, 1.5 meter accelerator is ready for operation except for certain components which are
unavailable as they are being used in the construction of munitions.
If this accelerator is completed
we believe we can accomplish a great deal.
At this moment the U.S.
plans to construct an
accelerator ten times as great but we are unsure as to whether they can accomplish this.
e previous March Nishina had discarded as impractical under wartime
conditions in Japan all methods of isotope separation except gaseous
thermal diffusion.
Otto Frisch had tried gaseous thermal diffusion (differing
from Philip Abelson’s liquid thermal diffusion) at Birmingham early in 1941
and proved it inadequate for separating uranium isotopes, but Nishina had
no knowledge of that secret work.
e Riken team had designed a thermal
column much like the laboratory-scale column Abelson had built at the
Naval Research Laboratory in Washington: of concentric 17-foot pipes, the
inner pipe heated to 750°F—electrically heated in the Riken configuration—
and the outer pipe cooled with water.
Nishina did not meet again with Nobuuji until seven months later, in
February 1944, when he reported difficulty producing uranium
hexafluoride.
His team had managed to develop a method for generating
elemental fluorine but had not yet been able to combine the gas with
uranium using an old and inefficient process that Abelson in the United
States had discarded before he began his thermal-diffusion studies.
Nishima
also had a problem with his diffusion column that Abelson would have
appreciated: it leaked.
“To achieve an airtight system,” Nishina told Nobuuji,
“we used [sealing] wax and finally achieved our goal.
Solder could not be
used because of the corrosive properties of the fluorine.” He was “in the
middle of developing this [hexafluoride-generating] process but can see the
end in sight.” His 1.5 -meter cyclotron was now in operation but only at low
energy; his explanation for that compromise comments pointedly on the
condition of the Japanese industrial economy by 1944:
We have been unable to obtain any superior, high-frequency-generating vacuum tubes...
for the
cyclotron....
As a result of this constraint, the low operating voltages limit the population of
neutrons we can produce....
In order to liberate many high-energy neutrons, a high-voltage vacuum tube is required.
But, unfortunately, they are difficult to acquire.
By summer Nishina’s group had manufactured some 170 grams of
uranium hexafluoride—in the United States hex was now being produced by
the ton—and in July attempted a first thermal separation.2174 Gauges at the
top and bottom of the column, intended to measure a difference in pressure
—showing that separation was taking place—indicated no difference at all.
“Well, don’t worry,” Nishina told his team.
2175 “Just keep on with it, just keep
giving it more gas.” 2176
He reconvened with Nobuuji on November 17, 1944, to report that “since
February of this year there has not been a great deal of progress.” He was
losing as much as half his hexafluoride to corrosion effects:
We thought the materials we had used to make this apparatus for working with the [hexafluoride]
were made of impure metals.
erefore we next used the most highly-refined metals available for
the system.
However, they were still eaten away.
It was therefore necessary to reduce the pressure of
the system...
to compensate for this erosion.
e cyclotron was operating at higher but not yet full power; Nishina was
using it, he told Nobuuji, “to assay the concentrated, separated material.”
Significantly missing from the November 17 conference report is any
mention of measurable separation of U235 from U238.
Nishina’s staff had
understood for more than a year that he did not believe his country could
build an atomic bomb in time to affect the outcome of the war.2177 Whether
he continued research out of loyalty, or because he thought such knowledge
would be valuable aer the war, or to win support for his laboratory and
deferment from military service for his young men, the bare record does not
reveal.
On the occasion of the November 17 conference he once again
complained of the lack of sufficiently powerful vacuum tubes for his
cyclotron and told Nobuuji, contrary to the evidence of experiment, that the
Riken’s efforts at isotope separation were “now at a midpoint in their
practical solution.” Nobuuji might have been more helpful if he had
understood even the most basic facts of the work.
An exchange between the
two men late in the meeting indicates the military liaison was as innocent of
nuclear physics as a stone:
Nobuuji: If uranium is to be used as an explosive, 10 kg is required.
Why not use 10 kg of a conventional explosive?
Nishina: at’s nonsense.
A B-29, specially modified, first dropped an atomic bomb—a dummy in
Man—at Muroc Army Air Force Base in California on March 3, 1944.
Restrained by sway-bracing, a bomb hung singly in the B-29’s bomb bay
from a single release, and the first series of tests ended ignominiously that
season when a release cable loosened and dumped one onto closed bomb-
bay doors at 24,000 feet.
“e doors were then opened,” a technical report
notes, “and the bomb tore free, considerably damaging the doors.” 2178 A
second series of tests in June went better.
Word that Fat Man would be
heavier than previously estimated encouraged Norman Ramsey’s Delivery
group to replace the original bomb-release mechanism, which had been
modified from a standard glider tow release, with a sturdier British
Lancaster bomber design.
Lessons learned, the Air Force began modifying seventeen more B-29’s at
the Glenn L.
Martin plant in Omaha, Nebraska, in August; that month the
service prepared to train a special group to deliver the first atomic bombs.
e 393rd Bombardment Squadron, then based at Fairmont, Nebraska, in
training for Europe, would form the nucleus of the new organization.
Late in
August Henry H.
(“Hap”) Arnold, the commanding general of the U.S.
Army Air Forces, approved the assignment of an Illinois-born lieutenant
colonel, Paul W.
Tibbets, twenty-nine years old, to be group commander.
Tibbets may well have been the best bomber pilot in the Air Force.
He had
led the first B-17 bombing mission from England into Europe, had carried
Dwight Eisenhower to his Gibraltar command post before the invasion of
North Africa and had led the first bomber strike of that invasion.
More
recently he had been test-piloting the B-29, which in 1944 was just
beginning to come on line, working with the physics department of the
University of New Mexico in Albuquerque to determine how well the new
bomber could defend itself against fighter attack at high altitude.
He was a
man of medium height and stocky build with dark, wavy hair and a widow’s
peak, full-faced and square-jawed, a pipe smoker.
His father was a candy
wholesaler in Florida and a disciplinarian from whom Tibbets probably
acquired his reserved perfectionism; he was closer to his mother, the former
Enola Gay Haggard of Glidden, Iowa.
He had chosen an Air Force career, he
told a postwar interviewer, aer his mother had supported him in that
choice against his father’s opposition:
When I was in college, studying to be a doctor, I realized that I had always wanted to fly.
In 1936,
my desire to do something about it reached the point where a family showdown on the subject
developed.
During the discussion, a few tempers flared, but my mother never said a word.
In the
end, still undecided, I got her off to the side and asked her what she thought.
Despite the things
that had been said on the subject, and the fact that most of the people in the discussion had included the statement, “You’ll kill yourself in an airplane,” Mother said, quite calmly and with positive assurance, “You go ahead and fly.
You will be all right.” 2179
So far he had been, and now he had won a new assignment.
He flew to
Second Air Force headquarters in Colorado Springs at the beginning of
September 1944 to report to commanding Major General Uzal Ent.
An aide
installed him in the general’s anteroom.
An officer came out, introduced
himself, took Tibbets aside and asked him if he had ever been arrested.
Tibbets considered the situation and decided to answer honestly to this
stranger that he had been, as a teenager in North Miami Beach, caught in
flagrante delicto in the backseat of a car with a girl.
Lieutenant Colonel John
Lansdale, Jr., who was responsible to Groves for atomic bomb intelligence
and security, knew about the arrest and had questioned Tibbets to test his
honesty.
Now he led him into Ent’s office.
Norman Ramsey and Deke
Parsons were waiting there.
“I’m satisfied,” Lansdale said.
2180 e physicist
and the Navy officer briefed Tibbets on the Manhattan Project and the
Muroc bombing tests.
Lansdale cautioned him at length on security.
Aer
the three men le, Ent specified Tibbets’ assignment.
“You have to put
together an outfit and deliver this weapon,” the pilot remembers the Second
Air Force commander saying.
“We don’t know anything about it yet.
We
don’t know what it can do....
You’ve got to mate it to the airplane and
determine the tactics, the training, and the ballistics—everything.
ese are
all parts of your problem.
is thing is going to be very big.
I believe it has
the potential and possibility of ending the war.
”2181 e delivery program
within the Air Force had been codenamed Silverplate, Ent told him.
If
Tibbets needed anything, he had only to use that magic word; Arnold had
accorded it the highest priority in the service.
e Air Force chose Wendover Field, Utah, as home base for the new
organization.
2182 Tibbets flew to Utah early in September, looked the base
over and liked what he saw.
It was sited between low mountain ranges on the
desert salt flats in gritty and secure isolation 125 miles west of Salt Lake City
near the Utah-Nevada border; the flat basin, the sink of an ancient and
enormous freshwater lake of which the Great Salt Lake is a brackish
remnant, offered miles of desolation for bombing practice.
Pioneers bound
for California had suffered the crossing once—their wagon ruts could still be
viewed nearby.
e 393rd moved to Wendover in September and with the
addition of troop-carrier and other support components became the 509th
Composite Group.
In October it began receiving its new B-29’s.2183
A Boeing product, the B-29 was a revolutionary aircra, the first
intercontinental bomber.
It was conceived in the late 1930s by ambitious
officers within what was then still the Army Air Corps as the vehicle of their
vision of wars fought at great distance by strategic air power.
As early as
September 1939 they proposed its use from bases in the Philippines, Siberia
or the Aleutians in the event of war against Japan.
2184 It was the world’s first
pressurized bomber and at 70,000 pounds the heaviest production bomber
ever built, 135,000 pounds loaded, a weight that required an 8,000-foot
runway to lumber airborne.
In appearance it was a sleek, polished-
aluminum tube 99 feet long intersected by huge 141-foot wings—two B-29’s
would fill a football field—with a classic sinusoidal tail nearly three stories
tall.
Four Wright 18-cylinder radial engines that each developed 2,200
horsepower propelled it at altitude at 350 miles per hour maximum speed—
it cruised at 220—and it was designed to fly a 4,000-mile mission with up to
20,000 pounds of bombs, though 12,000 pounds was nearer its operational
load.
It could cruise above 30,000 feet, out of range of flak and of most
enemy fighters.
Turbosuperchargers boosted engine power; outsized 16.5 -
foot propellers turned more slowly than those of any other aircra; wing
flaps, the world’s largest, adjusted a fih of wing area to adapt the high-
speed, long-range, low-drag wing for takeoff and landing.
On the ground the B-29 rested level on three point landing gear:
retractable wheels at the nose and under each wing.
e plane’s eleven-man
crew occupied two pressurized sections within the five joined sections of the
fuselage; tandem bomb bays fore and a of the wings separated the nose
section from the waist and tail, and to pass back from the nose to the waist
required crawling through a pressurized one-man tunnel.
e standard B-29
crew counted pilot, copilot, bombardier, flight engineer, navigator and radio
operator in the nose section, three gunners and a radar operator in the waist
and another gunner in the tail.
Because electrical wiring was less vulnerable
to battle damage than pneumatic or hydraulic tubing, the aircra systems
with the exception of the hydraulic wheel brakes operated entirely on
electric motors, more than 150 in all, with a gasolinepowered donkey engine
in the rear fuselage supplying current on the ground.
Analog computers ran
a central gun-control system, but all the guns were stripped from 509th
bombers except the 20-millimeter cannon in the tail.
If the B-29’s engines were powerful they were also notoriously susceptible
to fires.
To improve their horsepower-to-weight ratio Wright had used
magnesium for their crankcases and accessory housings.
Engine cooling was
inadequate and exhaust valves tended to overheat and stick; an engine would
then sometimes swallow a valve and catch fire.
If the fire reached the
magnesium, a metal commonly used in incendiary bombs, the engine would
usually burn through the main wing spar and peel off the wing.
To prevent
such disasters Boeing improved engine cooling but the basic design fault
persisted; there was no time to develop a new power plant if the aircra was
to serve the war for which it was invented.
(One Delivery group physicist
remembers skimming along at Wendover for miles aer takeoff, mowing
sagebrush, to cool the engines before climbing to altitude.2185 )
Once at altitude the flight crews of the 509th practiced bombing runs,
bombardiers aiming from above 30,000 feet through their Norden
bombsights at progressively smaller target circles limed on the ground.
Crews that had flown in cloudy Europe wondered why they were training in
visual bombing; an odd evasive maneuver instructed them at least in the
explosive potential of the unknown weapon they would carry.
Tibbets
briefed no one on the atomic bomb but directed his crews to nose their
aircra over into a sharp 155-degree diving turn immediately aer bomb
release.
Diving the huge bombers rapidly increased their airspeed; by
perfecting the maneuver the crews could escape ten miles from the delayed
explosion, “safe from destruction” by a bomb of 20,000 tons TNT equivalent,
writes Groves, “by a factor of two.
”2186 Before they practiced their diving
turns they dropped bombs of concrete and bombs filled with HE.
ese
crudely riveted Fat Man imitations, painted bright orange for visibility, they
called Pumpkins.
e 509th worked hard; the winter wind howled over the
Wendover reservation, trapping tumbleweeds on the barbed-wire fences;
crews careened into Salt Lake City on weekends to blow out.
Tibbets opened
their mail, bugged their telephones, had them followed and shipped off
those who broke security to the secure but miserable Aleutians for the
duration of the war.
2187 He held authority over 225 officers and 1,542
enlisted men.
With his silverplated requisitions he commandeered from
around the world the best pilots, bombardiers, navigators and flight
engineers he could find.
One of them, Captain Robert Lewis of Brooklyn, New York, stocky and
blond, twenty-six years old, an abrasive but gied pilot whom Tibbets had
personally trained, had spent part of the summer of 1944 at Grand Island,
Nebraska, teaching a senior officer with hundreds of combat hours behind
him to fly B-29’s.
us checked out, Major General Curtis LeMay rode a C-
54 to India late in August to take over the 20th Bomber Command, based in
India with forward airfields in China from which it was attempting with
fewer than two hundred B-29’s to bomb Japan.
e bombers had to ferry
their own fuel and ordnance from India to China over the Himalayas before
each mission—seven supply flights for each bombing strike, up to twelve
gallons burned for each one gallon delivered.
“It didn’t work,” LeMay writes
in his autobiography.
“No one could have made it work.
It was founded on
an utterly absurd logistic basis.
Nevertheless, our entire Nation howled like a
pack of wolves for an attack on the Japanese homeland.
”2188
Curtis LeMay was a wild man, hard-driving and tough, a bomber pilot, a
big-game hunter, a chewer of cigars, dark, fleshy, smart.
“I’ll tell you what
war is about,” he once said bluntly—but he said it aer the war—“you’ve got
to kill people, and when you’ve killed enough they stop fighting.” 2189
rough most of the war he seems to have held to the preference for
precision bombing over area bombing that had distinguished the U.S.
Air
Force from the British since Churchill’s and Cherwell’s intervention of 1942.
Sometimes in Europe precision bombing had served, though never
decisively.
Over Japan, so far, it had failed.
And failure was LeMay’s bete
noire.
His father had been a failure, an odd-job drier, forever moving his family
around.
e LeMays lived all over Ohio, in Pennsylvania, out in the wilds in
Montana, in California.
Curtis Emerson LeMay, born in Columbus, Ohio, in
1906, was the first of seven children.
e two memories of early childhood
he chooses to offer in his autobiography are linked.
Of first seeing an
airplane and chasing it madly: “I wanted not only the substance of the
mysterious object, not only that part I could have touched with my hands.
I
wished also in vague yet unforgettable fashion for the drive and speed and
energy of the creature.
”2190 And of compulsively running away from home:
“truancy” that “bordered on mania,” his mother told him.2191 “I had to grow
older,” LeMay writes, “and be burdened with a lot of responsibilities, and
begin to nourish ambition—I had to do these things before I could manage
to control my temper and discipline my activities.” 2192
He delivered telegrams and packages and boxes of candy.
He delivered
newspapers, sold newspapers, wholesaled newspapers to delivery boys,
supporting himself and sometimes his family: “When the grocer hesitates
about putting that latest basket of groceries on the bill, then you’d better be
ready to come up with cash in hand.
Very early in life I was convinced
bitterly of this necessity....
e larder was a vague mystery which Pop didn’t
bother to penetrate.” 2193 LeMay resented the missing childhood but moved
on.
He paid his own way through Ohio State by working nights at a steel
foundry.
ROTC in college led to the Ohio National Guard because the
Guard had higher priority on Army flying-school enrollments than the
Army Reserve.
He won his wings in 1929 and never looked back: mess
officer, navigation officer, General Headquarters navigator, B-10’s, B-17’s.
In
England in 1943 and 1944 he worked night and day to improve precision
bombing.
He won quick promotion.
Arnold sent him to the Pacific because he needed someone who could get
the job done:
General Arnold, fully committed to the B-29 program all along, had crawled out on a dozen limbs
about a thousand times, in order to achieve physical resources and sufficient funds to build those
airplanes and get them into combat....
So he finds they’re not doing too well.
He has to keep
juggling missions and plans and people until the B-29s do do well.
General Arnold was absolutely
determined to get results out of this weapons system.
2194
e B-29 had to be used, that is, successfully used, or men who had staked
their careers and their convictions would be shamed, resources squandered
that might have aided elsewhere in the war, lives lost futilely and millions of
dollars wasted.
e justification recurs.
e first B-29 to arrive in the Marianas landed on Saipan on October 12,
1944.
Brigadier General Haywood S.
Hansell, Jr., assigned to lead the 21st
Bomber Command, flew it.
As Arnold’s chief of staff Hansell had helped
formulate the doctrine of precision bombing and believed strongly in its
central premise—that wars could be won by selectively destroying the
enemy’s key industries of war.
2195, 2196 A stream of new bombers followed the new commander out to the Marianas; the first U.S.
aircra to fly over
Tokyo since the Doolittle raid of 1942 was a B-29 on November 1 soaring
high and light on a photoreconnaissance mission.
A French journalist living
in Tokyo at the time, Robert Guillain, remembers his sense of anticlimax:
e city waited.
Millions of lives were suspended in the silence of the radiant autumn aernoon.
For a moment, antiaircra fire shook the horizon with a noise of doors slamming in the sky.
en
—nothing: the all-clear was sounded without sight of a plane.
e radio announced that a single B-
29 had flown over the capital without dropping any bombs.
at seemed a reprieve and for a time only reconnaissance missions
disturbed the ill-defended city.
“One day the visitor finally appeared, flying
at 35,000 feet,” Guillain continues; “he even le his signature chalked on the
blue sky: a line of pure white like some living thing that seemed to nose an
almost imperceptible silver fly ahead of it.” Back in the Marianas Hansell was
teaching his men to navigate together, to fly in formation; they had trained
in the United States only as individual crews.
Hansell received his first target directive on November 11.
e Joint
Chiefs of Staff had approved it and it reflected their conviction that bombing
and naval blockade alone could not bring the Pacific war to a timely end.
In
September the Combined Chiefs—British and American together—had
established a planning date for the end of the war: eighteen months aer the
defeat of Germany.
e U.S.
Joint Chiefs judged an invasion of the Japanese
home islands essential to achieve that goal.
e target directive Hansell
received therefore gave first priority to the precision bombing of the
Japanese aircra industry (to cripple Japanese air defenses before an
American invasion), second priority to supporting Pacific operations
(MacArthur was even then reoccupying the Philippines, returning as he had
promised he would) and third priority to testing the efficacy of area
incendiary attacks.
ese priorities, putting precision bombing first, suited
Hansell’s own.
His crews flew their first raid on Japan from Saipan on November 24.
eir target was the Musashi aircra engine factory north of Tokyo ten
miles from the Imperial Palace.
A hundred planes began the mission.
Seventeen aborted; six were unable to release their bombs.
Flak was heavy
and the target buried in undercast.
But totally unexpected at the high
altitude at which the bombers flew was a 140-mile-per-hour wind.
ey
were blown with it over the target and their ground speed was therefore
nearly 450 mph, impossible for the bombardiers.
As a result only twenty-
four planes managed to bomb the factory area—the rest scattered their loads
over the docks and warehouses around Tokyo Bay—and only sixteen bombs
hit the target.
“I did not anticipate the extremely high wind velocities above
thirty thousand feet,” Hansell said later, “and they came as a very
disagreeable surprise.
”2197 e Air Force had discovered the jet stream.
LeMay was then still working with his 20th Bomber Command out of
India and China.
Supporting the indifferent military campaigns of Chiang
Kai-shek was an activity he abhorred but was sometimes forced to perform.
For six months Claire Chennault, the leathery Texan who headed the U.S.
air
staff assigned to the Nationalist Chinese Army, had been promoting the
bombing of Hankow, the riverside city on the Yangtze five hundred miles
inland from Shanghai from which Japan supplied its Asian mainland armies.
With a renewed Japanese drive in interior China in November Chennault
pressed for a Hankow attack.
LeMay resisted diverting his command from
Japanese home-island targets; the Joint Chiefs had to compel his
participation.
B-24’s and B-25’s were also massing for the strike; Chennault
particularly wanted LeMay to load his aircra with incendiaries and bomb
from 20,000 feet rather than from above 30,000 feet in order to sow a denser
pattern.
LeMay reserved one aircra in five for high explosives.
Seventy-
seven B-29’s took part in the raid on December 18 and burned the Hankow
river district down; fires raged out of control for three days.
e lesson was
not lost on Washington, nor on LeMay.
At Los Alamos the same week Groves, Parsons, Conant, Oppenheimer,
Kistiakowsky, Ramsey and several other leaders met in Oppenheimer’s office
to discuss preparing Pumpkins—they called them blockbusters—for
Tibbets’ 509th Composite Group.
2198 e first Fat Man design, the 1222, had
already been changed because it had proved so difficult to assemble—
assembly required inserting, threading nuts onto and tightening more than
1,500 bolts—and redesign meant the loss of about 80 percent of the tooling
work done at the Pacific Aviation Company in Los Angeles through the
autumn.
e first unit of a new, simpler design, the 1291, would be ready in
three days, on December 22.
“Captain Parsons said that the blockbuster
production for the 1291 gadget between 15 February and 15 March would
require a minimum of 30 blockbusters,” the minutes of the meeting report,
“so that each B-29 could drop at least two....
An additional 20 blockbusters
should be produced for H.E.
testing....
Following that, 75 units should be
produced for overseas shipment.
”2199
Groves wanted none of it.
He wanted no dummy 1291’s drop-tested
outside the continental United States and he saw no reason to build 75
Pumpkins for overseas target practice for Tibbets’ crews.
It was the end of
1944 and he was feeling the pressure of accumulating Manhattan Project
delays: “General Groves indicated that too much valuable time was being
taken from other problems to devote time to the blockbuster program.”
Conant asked how long the blockbuster program would have to continue;
Parsons answered combatively that it would have to continue as long as
Tibbets’ group operated so that 509th crews could maintain their bombing
skills.
He relented to reveal that “Colonel Tibbets’ Group expected to reach
peak combat training by 1 July.”
Since Parsons had not succeeded in person in convincing Groves of the
importance of bomb-assembly and bombing practice he wrote the general a
forceful memorandum on the day aer Christmas.
ere were major
differences, he pointed out, between the “gun gadget” and the “implosion
gadget,” particularly in terms of final assembly:
It is believed fair to compare the assembly of the gun gadget to the normal field assembly of a torpedo, as far as mechanical tests are involved....
e case of the implosion gadget is very different, and is believed comparable in complexity to rebuilding an airplane in the field.
Even this
does not fully express the difficulty, since much of the assembly involves bare blocks of high
explosives and, in all probability, will end with the securing in position of at least thirty-two boosters and detonators, and then connecting these to firing circuits, including special coaxial
cables and high voltage condenser circuit....
I believe that anyone familiar with advance base operations...
would agree that this is the most complex and involved operation which has ever
been attempted outside of a combined laboratory and ammunition depot.
Parsons’ simple and compelling point: the assembly team as well as the
bombardiers needed practice.
Groves relented; Tibbets got his Pumpkins.
More conventional bombs were falling regularly now on Japan, if not yet
to devastating effect.
Robert Guillain, the French journalist, remembers the
first night raid over Tokyo at the end of November:
Suddenly there was an odd, rhythmic buzzing that filled the night with a deep, powerful pulsation and made my whole house vibrate: the marvelous sound of the B-29s passing invisibly through a
nearby corner of sky, pursued by the barking of antiaircra fire....
I went up on my terrace roof....
e B-29s caught in the sweeping searchlight beams went tranquilly on their way followed
by the red flashes of ack-ack bursts which could not reach them at that altitude.
A pink light spread
across the horizon behind a near hill, growing bigger, bloodying the whole sky.
Other red splotches
lit up like nebulas else-where on the horizon.
2200 It was soon to be a familiar sight.
Feudal Tokyo was called Edo, and the people there had always been terrified by the frequent accidental fires they
euphemistically called “flowers of Edo.” at night, all Tokyo began to blossom.
While Parsons and Groves were debating Pumpkins, Lauris Norstad, who
had succeeded Hansell in Washington as Hap Arnold’s chief of staff when
Hansell moved to the Marianas, passed along word to his predecessor that a
trial fire raid on Nagoya, Japan’s third-largest city, was an “urgent
requirement.” Hansell resisted.
“With great difficulty,” he wrote Norstad, he
had “implanted the principle that our mission is the destruction of primary
targets by sustained and determined attacks using precision bombing
methods both visual and radar” and he was “beginning to get results.”
Ironically, he feared that area bombing would slacken his crews’ hard-won
skills.
Norstad sympathized but insisted that Nagoya was only a test, “a
special requirement resulting from the necessity of future planning.” 2201
Nearly one hundred of Hansell’s B-29’s flew incendiaries to Nagoya, at the
southern end of the Nobi Plain two hundred miles southwest of Tokyo, on
January 3, 1945, and started numerous small fires that resisted coalescing.
In three months of hard flying, taking regular losses, Hansell had
managed to destroy none of his nine high-priority targets.
His
determination not to rise to the bait Washington was offering—Billy
Mitchell, the Air Force’s earliest strategic champion, had pointed out the
vulnerability of Japanese cities to fire as long ago as 1924—doomed his
command.
Norstad flew out to Guam to relieve Hansell of duty on January
6.
Curtis LeMay arrived from China the next day.
“LeMay is an operator,”
Norstad told Hansell, “the rest of us are planners.
at’s all there is to it.” 2202
As if to encourage the new commander to independence, Hap Arnold
suffered a major heart attack on January 15 and withdrew for a time to
Miami sunshine to heal.
LeMay officially took command on January 20.
He had 345 B-29’s in the
Marianas and more arriving.
He had 5,800 officers and 46,000 enlisted men.
And he had all Hansell’s problems to solve: the jet stream; the terrible
Japanese weather, seven days of visual bombing a month with luck and not
much weather prediction because the Soviets refused to cooperate from
Siberia, whence the weather came; B-29 engines that overheated and burned
out while straining up the long climb to altitude; indifferent bombing:
General Arnold needed results.
Larry Norstad had made that very plain.
In effect he had said: “You
go ahead and get results with the B-29.
If you don’t get results, you’ll be fired.
If you don’t get results, also, there’ll never be any Strategic Air Forces of the Pacific....
If you don’t get results it
will mean eventually a mass amphibious invasion of Japan, to cost probably half a million more
American lives.
”2203
LeMay set his crews to intensive training.
ey were beginning to get
radar units and he saw to it that they were able at least to identify the
transition from water to land.
He ordered high-altitude precision strikes but
experimented with firebombing as well; 159 tons on Kobe on February 3
burned out a thousand buildings.
Not good enough: “another month of
indifferent operations,” LeMay calls February:2204
When I summed it all up, I realized that we had not accomplished very much during those six or
seven weeks.
We were still going in too high, still running into those big jet stream winds upstairs.
Weather was almost always bad.
I sat up nights, fine-tooth-combing all the pictures we had of every target which we had
attacked or scouted.
I examined Intelligence reports as well.
Did actually very much in the way of low-altitude flak exist up there in Japan?
I just couldn’t
find it.
ere was food for thought in this.
ere was food for thought as well in two compelling February horrors.
One occurred halfway around the world, in Europe, where LeMay had flown
so oen before.
e other began nearby.
e hardbitten general from Ohio
who despised failure and was failing in Japan could not have avoided
learning in detail of both.
e European event was the bombing of Dresden, the capital of the
German state of Saxony, on the Elbe River 110 miles south of Berlin, famous
for its art and its graceful and delicate architecture.
In February 1945 the
Russian front advanced to less than eighty miles to the east; refugees
streamed west from that deadly harrowing and into the Saxon city.
Lacking
significant war industry, Dresden had not been a bombing target before and
was essentially undefended.
It counted in its suburbs 26,000 Allied prisoners
of war.
Winston Churchill instigated the Dresden raid.
2205 e Secretary of State for Air responded to a phone call from the Prime Minister sometime in
January with tactical proposals; the P.M.
countered as testily as he had
countered in the matter of Niels Bohr:
I did not ask you last night about plans for harrying the German retreat from Breslau.
On the
contrary, I asked whether Berlin, and no doubt other large cities in East Germany should not now
be considered especially attractive targets.
I am glad that this is “under consideration.” Pray report
to me tomorrow what is going to be done.
2206
Dresden’s number thus came up.
On the cold night of February 13, 1,400
Bomber Command aircra dropped high explosives and nearly 650,000
incendiaries on the city; six planes were lost.
e firestorm that ensued was
visible two hundred miles away.
e next day, just aer noon, 1,350
American heavy bombers flew over to attack the railroad marshaling yards
with high explosives but found nine-tenths cover of cloud and smoke and
bombed a far larger area, encountering no flak at all.
e American novelist Kurt Vonnegut, Jr., was a young prisoner of war in
Dresden at the time of the attack.
He described his experience to an
interviewer long aer the war:
e first fancy city I’d ever seen.
A city full of statues and zoos, like Paris.
We were living in a slaughterhouse, in a nice new cement-block hog barn.
ey put bunks and straw mattresses in the
barn, and we went to work every morning as contract labor in a malt syrup factory.
e syrup was
for pregnant women.
e damned sirens would go off and we’d hear some other city getting it—
whump a whump a whumpa whump.
We never expected to get it.
ere were very few air-raid shelters in town and no war industries, just cigarette factories, hospitals, clarinet factories.
en a
siren went off—it was February 13, 1945—and we went down two stories under the pavement into
a big meat locker.
It was cool there, with cadavers hanging all around.
When we came up the city
was gone....
e attack didn’t sound like a hell of a lot either.
Whump.
ey went over with high
explosives first to loosen things up, and then scattered incendiaries....
ey burnt the whole damn town down....
2207
Every day [aerward] we walked into the city and dug into basements and shelters to get the
corpses out, as a sanitary measure.
When we went into them, a typical shelter, an ordinary
basement usually, looked like a streetcar full of people who’d simultaneously had heart failure.
Just
people sitting there in their chairs, all dead.
A fire storm is an amazing thing.
It doesn’t occur in
nature.
It’s fed by the tornadoes that occur in the midst of it and there isn’t a damned thing to
breathe.
We brought the dead out.
ey were loaded onto wagons and taken to parks, large, open
areas in the city which weren’t filled with rubble.
e Germans got funeral pyres going, burning
the bodies to keep them from stinking and from spreading disease.
One hundred thirty thousand
corpses were hidden underground.
Nearer at hand Curtis LeMay could see the intensity and ferocity of
Japanese resistance increasing as American forces fought their way toward
the home islands.
e latest hellhole was Iwo Jima—Sulfur Island—a mass of
volcanic ash and rock only seven square miles in area with a dormant
volcano at one end, Mount Suribachi, that had risen from the sea within
historic times.2208 Miasmic with sulfur fumes, a steam of rotten eggs, Iwo
lacked fresh water but supported two airfields from which Japanese fighter-
bombers departed to attack LeMay’s B-29’s shining on their hardstands on
Guam, Saipan and Tinian.
It was nine hundred miles closer to Tokyo than
the Marianas and its radar outposts gave Honshu antiaircra batteries and
defensive fighter units ample warning when B-29’s dispatched for strategic
assault passed overhead.
e Japanese understood the island’s strategic position and had prepared
for months, oen under bombardment from U.S.
Navy and Air Force
planes, to defend it.
Fieen thousand men turned Iwo Jima into a fortress of
bunkers, ditches, trenches, 13,000 yards of tunnels, 5,000 pillboxes and
fortified cave entrances, vast galleys and wards built into Suribachi,
blockhouses with thick concrete walls.
e emplacements were armed with
the largest concentration of artillery the Japanese had assembled anywhere
up to that day: coastal defense guns in concrete bunkers, fieldpieces of all
calibers shielded in caves, rocket launchers, tanks buried in the sand up to
their turrets, 675-pound spigot mortars, long-barreled anti-aircra guns
cranked down parallel to the ground.
e Japanese commander, Lieutenant
General Tadamichi Kuribayashi, taught his men a new strategy: “We would
all like to die quickly and easily, but that would not inflict heavy casualties.
We must fight from cover as long as we possibly can.
”2209 His soldiers and
marines, increased in strength now to more than 21,000, would no longer
throw away their lives in banzai charges.
ey would resist to the death.
“I
am sorry to end my life here, fighting the United States of America,”
Kuribayashi wrote his wife.
“But I want to defend this island as long as I
can.” 2210 He expected no rescue.
“ey meant to make the conquest of Iwo
so costly,” says William Manchester, who fought not this battle but the next
one, Okinawa, “that the Americans would recoil from the thought of
invading their homeland.” 2211
Washington secretly considered sanitizing the island with artillery shells
loaded with poison gas lobbed in by ships standing well offshore; the
proposal reached the White House but Roosevelt curtly vetoed it.
2212 It might have saved thousands of lives and hastened the surrender—arguments
used to justify most of the mass slaughters of the Second World War, and
neither the United States nor Japan had signed the Geneva Convention
prohibiting such use—but Roosevelt presumably remembered the world
outcry that had followed German introduction of poison gas in the First
World War and decided to leave the sanitizing of Iwo Jima to the U.S.
Marines.
ey began landing on Saturday, February 19, at 9 A.M., aer weeks of
naval barrage and bombing.
A less well-defended foe would have been
pulverized by that battering; the Japanese dug in on Iwo Jima were only
groggy from the long disturbance of their sleep.
e Navy ferried the
marines to shore in amphtracs, gave them over to the deep and treacherous
black pumice of the beaches and ran out to reload.
e Japanese
commanded Suribachi, the high ground; they had zeroed in on every point
of consequence on the flat island and now stood back to fire.
On the
beaches, says Manchester, men were more oen killed by artillery than by
bullets:
e invaders were taking heavy mortar and artillery fire.
Steel sleeted down on them like the lash
of a desert storm.
By dusk 2,420 of the 30,000 men on the beachhead were dead or wounded.
e
perimeter was only four thousand yards long, seven hundred yards deep in the north and a
thousand yards in the south.
It resembled Doré’s illustrations of the Inferno.
Essential cargo—
ammo, rations, water—was piled up in sprawling chaos.
And gore, flesh, and bones were lying all
about.
2213 e deaths on Iwo were extraordinarily violent.
ere seemed to be no clean wounds; just fragments of corpses.
It reminded one battalion medical officer of a Bellevue dissecting room.
Oen the only way to distinguish between Japanese and marine dead was by the legs; Marines
wore canvas leggings and Nips khaki puttees.
Otherwise identification was completely impossible.
You tripped over strings of viscera fieen feet long, over bodies which had been cut in half at the
waist.
Legs and arms, and heads bearing only necks, lay fiy feet from the closest torsos.
As night
fell the beach reeked with the stench of burning flesh.
Aer that first awful night, when the Japanese might have squandered
themselves in counterattacks but chose instead to hold fast to their defensive
redoubts, the leaders of the invasion understood that they would pay with
American lives for every foot of the island they captured.
Kuribayashi’s final
order to his men demanded of them the same sacrifice: “We shall infiltrate
into the midst of the enemy and annihilate them,” he exhorted.2214 “We shall
grasp bombs, charge the enemy tanks and destroy them.
With every salvo
we will, without fail, kill the enemy.
Each man will make it his duty to kill
ten of the enemy before dying!” Slow, cruel fighting continued for most of a
month.
In the end, late in March, when shell and fire had changed the very
landscape, victory had cost 6,821 marines killed and 21,865 wounded of
some 60,000 committed, a casualty ratio of 2 to 1, the highest in Marine
Corps history.
Of Japanese defenders, 20,000 died on Iwo Jima; only 1,083
allowed themselves to be captured.
at so many were dying to protect his B-29 crews when their results were
inconsequential to the war catalyzed LeMay to radical departure.
e deaths
had to be justified, the debt of death repaid.
One more incendiary test, 172 planes over Tokyo on February 23,
produced the best results of any bombing so far, a full square mile of the city
burned out.
But LeMay had long known that fire would burn down Japan’s
wooden cities if properly set.
Proper setting, not firebombing itself, was the
problem he struggled to solve.
He studied strike photographs.
He reviewed intelligence reports.
“e
Japanese just didn’t seem to have those 20- and 40-millimeter [antiaircra]
guns,” he remembers realizing.
“at’s the type of defense which must be
used against bombers coming in to attack at a low or medium altitude.
Up at
twenty-five or thirty thousand feet they have to shoot at you with 80- or 90-
millimeter stuff, or they’re never going to knock you down....
But 88-
millimeter guns, if you come in low, are impotent.
You’re moving too
fast.” 2215
Low-altitude firebombing had other important advantages.
Flying low
saved fuel coming and going from the Marianas: the B-29’s could carry more
bombs.
Flying low put less strain on the big Wright engines: fewer aircra
would have to abort or ditch.
LeMay added in another variable and
proposed to bomb at night; his intelligence sources indicated that Japanese
fighters lacked airborne radar units.
With little or no light flak or fighter
cover Tokyo would be nearly defenseless.
Why not, then, LeMay reasoned,
take out B-29 guns and gunners and further increase the bomb load?
He
decided to leave the tail gunner as an observer and pull the rest.
2216
He discussed his plan with only a few members of his staff.
ey worked
out a target zone, a flat, densely crowded twelve square miles of workers’
houses adjacent to the northeast corner of the Imperial Palace in central
Tokyo.
Even two decades aer the war LeMay felt the need to justify the site
as in some sense industrial: “All the people living around that Hattori factory
where they make shell fuses.
at’s the way they disperse their industry:
little kids helping out [at home], working all day, little bits of kids.
”2217 e
U.S.
Strategic Bombing Survey notes frankly that 87.4 percent of the target
zone was residential, and LeMay goes on to more candid admission later in
his autobiography:2218
No matter how you slice it, you’re going to kill an awful lot of civilians.
ousands and thousands.
But, if you don’t destroy the Japanese industry, we’re going to have to invade Japan.
And how many
Americans will be killed in an invasion of Japan?
Five hundred thousand seems to be the lowest
estimate.
Some say a million.
2219
...
We’re at war with Japan.
We were attacked by Japan.
Do you want to kill Japanese, or would
you rather have Americans killed?
A little later in the war a spokesman for the Fih Air Force would point out
that since the Japanese government was mobilizing civilians to resist
invasion, “the entire population of Japan is a proper military target.
”2220
Onto the proper military target of working-class Tokyo LeMay decided to
drop two kinds of incendiaries.
His lead crews would carry M47’s, 100-
pound oil-gel bombs, 182 per aircra, each of which was capable of starting
a major fire.
Behind those crews his major force would sow M69’s, 6-pound
gelled-gasoline bombs, 1,520 per aircra.
He eschewed magnesium bombs
because those more rigid weapons smashed all the way through the tile roofs
and light wooden floors of Japanese houses and buried themselves
ineffectually in the earth.
LeMay also remembers including a few high
explosives in the mix to demoralize the firemen.
He delayed seeking approval of his plan until the day before the raid was
scheduled to go, taking responsibility for it himself and determined to risk
the gamble.
Norstad approved on March 8 and alerted the Air Force public
relations staff to the possibility of “an outstanding strike.” 2221 Arnold was
informed the same aernoon.2222 LeMay’s crews were stunned to hear they
would fly their sorties unarmed at staggered levels between five and seven
thousand feet.
“You’re going to deliver the biggest firecracker the Japanese
have ever seen,” LeMay told them.2223 Some of them thought he was crazy
and considered mutiny.
Others cheered.
From Guam first, from Saipan next and then from Tinian 334 B-29’s took
off for Tokyo in the late aernoon of March 9.
ey were loaded with more
than 2,000 tons of incendiaries.
ey flew toward a city that an Associated Press correspondent who knew
it well had described in 1943 in a best-selling book as “grim, drab and
grubby.” 2224 Freed from Japanese detention in Manila and then in Shanghai,
Russell Brines had brought home a message about the people he had lived
among before the war and whose language he spoke:
“We will fight,” the Japanese say, “until we eat stones!” e phrase is old; now revived and ground
deeply into Japanese consciousness by propagandists skilled in marshaling their sheeplike
people....
[It] means they will continue the war until every man—perhaps every woman and child
—lies face downward on the battlefield.
ousands of Japanese, maybe hundreds of thousands,
accept it literally.
To ignore this suicide complex would be as dangerous as our pre-war oversight of
Japanese determination and cunning which made Pearl Harbor possible....2225
American fighting men back from the front have been trying to tell America this is a war of
extermination.
ey have seen it from foxholes and barren strips of bullet-strafed sand.
I have seen
it from behind enemy lines.
Our picture coincides.
is is a war of extermination.
e Japanese
militarists have made it that way.
2226
e fighting men of the Navy and the Air Force had seen particular
evidence of Japanese doggedness that autumn and winter in the appearance
of kamikazes, planes loaded with high explosives and deliberately flown to
ram ships.
Between October and March young Japanese pilots, most of them
barely qualified university students, sacrificed themselves in some nine
hundred sorties.
Navy fighters and antiaircra guns shot most of the
kamikazes down.
About four hundred U.S.
ships were hit and only about
one hundred sunk or severely damaged in a fleet of thousands, but the
attacks were alien and terrifying; they served to confirm for Americans the
extent of Japanese desperation even as they further depleted Japan’s waning
air defenses.
LeMay’s pathfinders arrived first over Tokyo a little aer midnight on
March 10.
On the district of Shitamachi on the flatlands east of the Sumida
River where 750,000 people lived crowded into wood-and-paper houses they
marked a diagonal of fire and then crossed it to ignite a gigantic, glowing X.
At 0100 the main force of B-29’s came on and began methodically bombing
the flatlands.
e wind was blowing at 15 miles per hour.
e bombers
carried their 1,520 M69’s in 500-pound clusters that broke apart a few
hundred feet above the ground.
Main-force intervalometers—the bomb-bay
mechanisms that spaced the release of the clusters—had been set for 50-foot
intervals.
Each planeload then covered about a third of a square mile of
houses.
If only a fih of the incendiaries started fires, that was one fire for
every 30,000 square feet—one fire for every fieen or twenty closely spaced
houses.
Robert Guillain remembers a deadlier density:
e inhabitants stayed heroically put as the bombs dropped, faithfully obeying the order that each
family defend its own house.
But how could they fight the fires with that wind blowing and when a
single house might be hit by ten or even more of the bombs...
that were raining down by the
thousands?
As they fell, cylinders scattered a kind of flaming dew that skittered along the roofs,
setting fire to everything it splashed and spreading a wash of dancing flames everywhere.
2227
By 0200 the wind had increased to more than 20 miles per hour.
Guillain
climbed to his roof to observe:
e fire, whipped by the wind, began to scythe its way through the density of that wooden city....
A huge borealis grew....
e bright light dispelled the night and B-29’s were visible here and there
in the sky.
For the first time, they flew low or middling high in staggered levels.
eir long, glinting
wings, sharp as blades, could be seen through the oblique columns of smoke rising from the city,
suddenly reflecting the fire from the furnace below, black silhouettes gliding through the fiery sky
to reappear farther on, shining golden against the dark roof of heaven or glittering blue, like
meteors, in the searchlight beams spraying the vault from horizon to horizon....
2228 All the Japanese in the gardens near mine were out of doors or peering up out of their holes, uttering cries
of admiration—this was typically Japanese—at this grandiose, almost theatrical spectacle.
Something worse than a firestorm was kindled in Tokyo that night.
e
U.S.
Strategic Bombing Survey calls it a conflagration, begun when the high
wind heeled over the pillar of hot and burning gases that the fires had
volatilized and convection had carried up into the air:
e chief characteristic of the conflagration...
was the presence of a fire front, an extended wall of
fire moving to leeward, preceded by a mass of preheated, turbid, burning vapors.
e pillar was in
a much more turbulent state than that of [a] fire storm, and being usually closer to the ground, it
produced more flame and heat, and less smoke.
e progress and destructive features of the
conflagration were consequently much greater than those of [a] fire storm, for the fire continued to
spread until it could reach no more material....
e 28-mile-per-hour wind, measured a mile
from the fire, increased to an estimated 55 miles at the perimeter, and probably more within.
2229
An extended fire swept over 15 square miles in 6 hours.
Pilots reported that the air was so violent
that B-29s at 6,000 feet were turned completely over, and that the heat was so intense, even at that
altitude, that the entire crew had to don oxygen masks.
e area of the fire was nearly 100 percent
burned; no structure or its contents escaped damage.
e fire had spread largely in the direction of
the natural wind.
A bombardier who flew through the black turbulence above the
conflagration remembers it as “the most terrifying thing I’ve ever
known.” 2230, 2231
In the shallower canals of Shitamachi, where people submerged
themselves to escape the fire, the water boiled.
e Sumida River stopped the conflagration from sweeping more than
15.8 square miles of the city.
e Strategic Bombing Survey estimates that
“probably more persons lost their lives by fire at Tokyo in a 6-hour period
than at any [equivalent period of] time in the history of man.” e fire storm
at Dresden may have killed more people but not in so short a space of time.
More than 100,000 men, women and children died in Tokyo on the night of
March 9-10, 1945; a million were injured, at least 41,000 seriously; a million
in all lost their homes.
Two thousand tons of incendiaries delivered that
punishment—in the modern notation, two kilotons.
But the wind, not the
weight of bombs alone, created the conflagration, and therefore the
efficiency of the slaughter was in some sense still in part an act of God.
Hap Arnold sent LeMay a triumphant telex: CONGRATULATIONS.
THIS
MISSION SHOWS YOUR CREWS HAVE GOT THE GUTS FOR ANYTHING.2232 Certainly
LeMay did; having gambled and succeeded, he quickly pushed on.
His B-29’s
firebombed Nagoya on March 11; firebombed Osaka by radar on March 13;
firebombed Kobe on March 16—stocks of M69’s were running low and
M17A1 clusters of 4-pound magnesium thermite bombs, less effective, had
to be substituted; firebombed Nagoya again on March 18.
“en,” says
LeMay, “we ran out of bombs.
Literally.” 2233 In ten days and 1,600 sorties the
Twentieth Air Force burned out 32 square miles of the centers of Japan’s four
largest cities and killed at least 150,000 people and almost certainly tens of
thousands more.
2234 “I consider that for the first time,” LeMay wrote
Norstad privately in April, “strategic air bombardment faces a situation in
which its strength is proportionate to the magnitude of its task.
I feel that the
destruction of Japan’s ability to wage war lies within the capability of this
command.
”2235 He had found a method, LeMay had begun to believe,
whereby the Air Force might end the Pacific war without invasion.
* * *
At Oak Ridge guests removed their shoes before entering a house.
Hiring
was still increasing on the muddy Tennessee reservation and construction
continuing, challenges to the meager ground cover that a Tennessee
Eastman employee was moved to immortalize anonymously in verse:
In order not to check in late, 2236
I’ve had to lose a lot of weight,
From swimming through a fair-sized flood
And wading through the goddam mud.
I’ve lost my rubbers and my shoes
Perpetually I have the blues
My spirits tumble with a thud
Because of all this goddam mud.
It’s in my system so that when
I cut my finger now and then
Instead of bleeding just plain blood
Out pours a stream of goddam mud.
Mud measured progress: Ernest Lawrence’s calutrons, built at such great
expense, had begun enriching uranium.
A minimum of 100 grams per day—
3.5 ounces—of 10 percent U235 came through the Alpha racetracks
beginning in late September 1944.2237 But poor planning for chemical
recovery of that feed from the Beta tanks wasted some 40 percent of it, as
Mark Oliphant reported to James Chadwick from Oak Ridge early in
November: “is loss or hold-up...
has resulted in a very serious delay in
the production of material for the first weapon....2238 e chemistry,
viewed as a whole, I believe to present an appalling example of lack of
coordination, of inefficiency, and bad management.”
A copy of Oliphant’s complaint went to Groves, who must have acted
quickly; the troubleshooting Australian physicist could report to the general
two weeks later that “the output from the beta tracks has shown an abrupt
and very satisfying upward trend.” In his letter to Chadwick, Oliphant had
noted a Beta output of only 40 grams per day; now “an output of about 90
grams per day [has] been reached and there [is] reason for believing that
this level would be maintained, or even increased, during the coming
months.” He concluded optimistically that “there is now a definite hope that
continued effort on the part of the operating company and others will lead
early in the New Year to a plant output of the order of that expected.
”2239
As of January 1945 on any given day about 85 percent of some 864 Alpha
calutron tanks operated to produce 258 grams—9 ounces—of 10 percent
enriched product; at the same time 36 Beta tanks converted the accumulated
Alpha product to 204 grams—7.2 ounces—per day of 80 percent enriched
U235, sufficient enrichment to make a bomb.
James Bryant Conant
calculated in his handwritten history notes on January 6 that a kilogram of
U235 per day would mean one gun bomb every six weeks.2240 , 2241 It follows that the gun bomb required about 42 kilograms—92.6 pounds, about 2.8
critical masses—of U235.
2242 Without further improvement the calutrons
alone could produce that much material in 6.8 months, and Conant noted
aer conferring with Groves that “it looks as if 40-45 kg...
will be obtained
by July 1.” Ernest Lawrence’s monumental effort had succeeded; every gram
of U235 in the one Little Boy that should be ready by mid-1945 would pass
at least once through his calutrons.
Conant also contrasted his assumptions of June 1944 with his assumptions
at the beginning of the new year to draw up a problematic balance sheet:
while he had previously “believed a few bombs might do the trick” of ending
the war, at the beginning of 1945 he was “convinced many bombs will now
be required (German experience).” e German experience was probably
the determined German resistance that was prolonging the war in Europe,
particularly the counteroffensive through the Ardennes known as the Battle
of the Bulge that had begun in mid-December and still threatened Allied
lines at the time of Conant’s notes.
It was partly Allied frustration with such
continuing resistance that would lead in another month to the atrocity of the
Dresden bombing.
Houdaille-Hershey was finally delivering satisfactory barrier tubes for the
K-25 gaseous-diffusion plant.
Union Carbide had scheduled barrier delivery
to take advantage of K-25’s organization as a cascade; as individual tanks,
called converters, arrived, workers hooked them into the system and tested
them for leaks in atmospheres of nitrogen and helium with the portable
mass spectrometers that Alfred Nier had designed.
When a stage was
leakproof and otherwise ready it could be operated without further delay,
and the first stage of the enormous K-25 cascade was charged with uranium
hexafluoride on January 20, 1945.
Enrichment by gaseous barrier diffusion
in the most advanced automated industrial plant in the world had begun.
It
would proceed efficiently with only normal maintenance for decades.
e pipes in Philip Abelson’s scaled-up thermal-diffusion plant, S-50,
leaked so badly they had to be welded, which delayed production, but all
twenty-one racks had begun enriching uranium by March.
Juggling the
different enrichment processes to produce maximum output in minimum
time then became a complex mathematical and organizational challenge.
Lieutenant Colonel Kenneth D.
Nichols, Groves’ talented and long-suffering
assistant, worked out the scheduling.
Based on Nichols’ schedule Groves
decided in mid-March not to build more Alpha calutrons, as Lawrence had
proposed, but to construct instead a second gaseous-diffusion plant and a
fourth Beta plant.
ough he certainly expected his atomic bombs to end
the war, Groves seems to have justified the new construction by the Joint
Chiefs’ conservative estimate that the Pacific war would end eighteen
months aer the European; his new plants could not be completed before
February 15, 1946, he explained in his proposal, but “on the assumption that
the war with Japan will not be over before July, 1946, it is planned to proceed
with the additions to the two plants unless instructions to the contrary are
received.” 2243 Perhaps he was simply being prudent.
Early in 1945 Oak Ridge began shipping bomb-grade U235 to Los
Alamos.
Between shipments Groves took no chances with a substance far
more valuable gram for gram than diamonds.
Although the Army had
condemned all the land and ejected the original inhabitants from the
Clinton reservation area, at the dead end of a dusty reservation back road
cattle grazed in a pasture beside a white farmhouse.2244 A concrete silo
towered over the road, which was sheltered by a steep bluff.
From the air the
scene resembled any number of small Tennessee holdings, but the silo was a
machine-gun emplacement, the farm was manned by security guards, and
built into the side of the bluff a concrete bunker shielded a bank-sized vault
completely encircled with guarded walkways.
In this pastoral fortress Groves
stored his accumulating grams of U235.
Armed couriers transported it as
uranium tetrafluoride in special luggage by car to Knoxville, where they
boarded the overnight express to Chicago.
ey passed on the luggage the
next morning to their Chicago counterparts, who held reserved space on the
Santa Fe Chief.
Twenty-six hours later, in midaernoon, the Chicago
couriers debarked at Lamy, the stranded desert way station that served Santa
Fe.
Los Alamos security men met the train and completed the transfer to the
Hill, where chemists waited eagerly to reduce the rare cargo to metal.
Plutonium production at Hanford depended as much on chemical
separation as it did on chain-reacting piles.
e chemistry was Glenn
Seaborg’s, spectacularly scaled up a billionfold directly from his team’s
earlier ultramicrochemical work.
e plutonium in the slugs irradiated in
the Hanford piles emerged mixed to the extent of only about 250 parts per
million with uranium and highly radioactive fission products.
Carrier
chemistry—the fractional crystallization of Marie Curie and Otto Hahn—
was therefore required to help the scant plutonium along.
e man-made
metal is extremely poisonous if ingested but only mildly radioactive.
To
make it safe to handle it also needed to be purified to less than 1 part in 10
million of fission products.
And because the pile slugs developed such a
burden of radioactivity, all but the final chemical processing had to be
carried out by remote control behind thick shielding.
2245
Seaborg’s team developed two separation processes to take advantage of
the different chemistries of plutonium’s several different valence states.
One
process used bismuth phosphate as a carrier; the other used lanthanum
fluoride.
Bismuth phosphate, scaled up directly from Met Lab experiments,
served the primary purpose of uranium and fission-product
decontamination.
Lanthanum fluoride, applied at pilot scale at Oak Ridge,
then concentrated the plutonium from the large volume of solution in which
it was suspended.
Hanford was the largest plant Du Pont had ever constructed and operated;
not least among its facilities were the chemical separation buildings.
“Originally eight separation plants were considered necessary,” writes
Groves, “then six, then four.
Finally, with the benefit of the operating
experience and information obtained from the Clinton semi-works, we
decided to build only three, of which two would operate and one would
serve as a reserve.” For safety the plants went up behind Gable Mountain ten
miles southwest of the riverside piles.
Each building was 800 feet long, 65
feet wide and 80 feet tall, poured-concrete structures so massive the workers
called them Queen Marys; the British ocean liner of that name was only a
fih again as long.
2246 e Queen Marys were essentially large concrete
boxes, says Groves, containment buildings “in which there were individual
cells containing the various parts involved in the process equipment.
To
provide protection from the intense radioactivity, the cells were surrounded
by concrete walls seven feet thick and were covered by six feet of concrete.”
Each Queen Mary contained forty cells, and each cell’s lid, which could be
removed by an overhead crane that rolled the length of the building’s long
canyon, weighed 35 tons.
Irradiated slugs ejected from a production pile
would be stored in pools of water 16.5 feet deep to remain until the most
intense and therefore short-lived of their fission-product radioactivities
decayed away, the water glowing blue around them with Cerenkov radiation,
a sort of charged-particle sonic boom.
e slugs would then move in
shielded casks on special railroad cars to one of the Queen Marys, where
they would first be dissolved in hot nitric acid.
A standard equipment group
occupied two cells: a centrifuge, a catch tank, a precipitator and a solution
tank, all made of specially fabricated corrosion-resistant stainless steel.
e
liquid solution that the slugs had become would move through these units
by steam-jet syphoning, a low-maintenance substitute for pumps.
ere
were three necessary steps to the separation process: solution, precipitation
and centrifugal removal of the precipitate.
ese would repeat from
equipment group to equipment group down the canyon of the separation
building.
e end products would be radioactive wastes, stored on site in
underground tanks, and small quantities of highly purified plutonium
nitrate.
Once the Queen Marys were contaminated with radioactivity no repair
crews could enter them.
Equipment operators had to be able to maintain
them entirely by remote control.
e operators trained at Du Pont in
Delaware, at Oak Ridge and on mockups at Hanford, but the engineer in
charge, Raymond Genereaux, sought more authoritative qualification.
And
found it: he required his operators, one hundred of whom arrived at
Hanford in October 1944, to install the process equipment into the first
completed separation building by remote control, pretending the canyon
was already radioactive.
ey did, awkwardly at first but with increasing
confidence as practice improved their remote-manipulation skills.
“When the Queen Marys began to function,” Leona Marshall remembers,
“dissolving the irradiated slugs in concentrated nitric acid, great plumes of
brown fumes blossomed above the concrete canyons, climbed thousands of
feet into the air, and dried sideways as they cooled, blown by winds
alo.” 2247 B-pile slugs traveled by rail into the 221-T separation plant
beginning on December 26, 1944.
“e yields in the first plant runs...
ranged between 60 and 70 per cent,” Seaborg notes proudly, and “reached 90
per cent early in February 1945.
”2248 Lieutenant Colonel Franklin T.
Matthias, Groves’ representative at Hanford, personally carried the first
small batch of plutonium nitrate by train from Portland to Los Angeles,
where he turned it over to a Los Alamos security courier.
ereaer
shipments—small subcritical batches in metal containers in wooden boxes
—traveled in convoy by Army ambulance via Boise, Salt Lake City, Grand
Junction and Pueblo to Los Alamos.
Bertrand Goldschmidt, the French chemist who worked with Glenn
Seaborg, puts the Manhattan Engineer District at the height of its wartime
development in perspective with a startling comparison.
It was, he writes in
a memoir, “the astonishing American creation in three years, at a cost of two
billion dollars, of a formidable array of factories and laboratories—as large
as the entire automobile industry of the United States at that date.” 2249
* * *
One of the mysteries of the Second World War was the lack of an early and
dedicated American intelligence effort to discover the extent of German
progress toward atomic bomb development.
If, as the record repeatedly
emphasizes, the United States was seriously worried that Germany might
reverse the course of the war with such a surprise secret weapon, why did its
intelligence organizations, or the Manhattan Project, not mount a major
effort of espionage?
Vannevar Bush had raised the question of espionage with Franklin
Roosevelt at their crucial meeting on October 9, 1941, when Bush apprised
the President of the MAUD Report, but the OSRD director got no
satisfactory answer, probably because the United States was not yet a
belligerent.
Groves in his memoirs passes the buck to the existing
intelligence agencies—Army G-2, the Office of Naval Intelligence and the
Office of Strategic Services, the forerunner of the CIA—and attributes the
inadequacy of their information to “the unfortunate relationships that had
grown up among [them].” 2250 Why he failed to confront the issue himself
until late 1943, when George Marshall asked him directly to do so, he
chooses not to say.
One reason was certainly security, a Groves obsession; in
order to know what to look for, intelligence agents would have to be briefed
on at least isotopeseparation technologies and nuclear-fission research,
which would mean that any agent captured or turned might well give
American secrets away.
When Groves finally did take responsibility for
intelligence gathering he picked scientific personnel who had not worked
within the Manhattan Project and authorized paramilitary operations to
advance only into areas already occupied.
at at least is how he intended
his intelligence unit to operate; in practice it frequently claimed its prizes in
the no-man’s-land between fighting fronts, by hook or by crook.
e unit Groves authorized in late 1943 somehow acquired the name
Alsos, Greek for “grove” and thus obscurely revealing; the brigadier thought
to have it renamed, “but I decided that to change it...
would only draw
attention to it.” 2251 To head the Alsos mission he chose Lieutenant Colonel
Boris T.
Pash, a former high school teacher turned Army G-2 security
officer, FBI trained, who had made himself notorious in domestic
intelligence circles for his flamboyant investigation of Communist activities
among members of the staff of Ernest Lawrence’s Berkeley laboratory.
Pash,
trim and Slavic, with rimless glasses and light, thin hair, spoke Russian
fluently and was a great hunter of Communists.
His background helps
explain why: his Russian emigré father was the Metropolitan—senior bishop
—of the Eastern Orthodox Church in North America.
It was Pash who had
interrogated Robert Oppenheimer about his Communist affiliations while a
clandestine recording device in the next room preserved the physicist’s
damaging evasions on blank sound motion picture film; he concluded
without hard evidence that Oppenheimer was a Communist Party member
gone underground and possibly a spy.
Whatever Groves thought of Pash’s
Red-baiting, he chose him to head Alsos because he delivered the goods:
“his thorough competence and great drive had made a lasting impression on
me.
”2252
Pash set up a base in London in 1944 as the Allied armies pushed through
France aer the Normandy invasion.
He then crossed the Channel with a
squad of Alsos enlisted men and wheeled toward Paris by jeep.
“e ALSOS
advance party joined the 102nd U.S.
Cavalry Group on Highway 188 at
Orsay,” a contemporary military intelligence report notes.
e American
force stopped outside Paris—Charles de Gaulle had persuaded Franklin
Roosevelt to allow the Free French to enter the city first—but Pash decided
to improvise: “Colonel Pash and party then proceeded to cut across-country
to Highway 20 and joined second elements of a French armored division.
2253
e ALSOS Mission then entered the City of Paris 0855 hrs., 25 August
1944.
e party proceeded to within the city in the rear of the first five
French vehicles to enter, being the first American unit to enter Paris.” e
five French vehicles were tanks.
In his unarmored jeep Pash drew repeated
sniper fire.
He dodged among the back streets of Paris and by the end of the
day had achieved his goal, the Radium Institute on the Rue Pierre Curie.
ere he settled in for the evening to drink celebratory champagne with
Frédéric Joliot.
Joliot knew less about German uranium research than anyone had
expected.
Pash moved his base to liberated Paris and began following up
promising leads.
One of the most significant pointed to Strasbourg, the old
city on the Rhine in Alsace-Lorraine, which Allied forces began occupying
in mid-November.
Pash found a German physics laboratory installed there
in a building on the grounds of Strasbourg Hospital.
His scientific
counterpart on the Alsos team was Samuel A.
Goudsmit, a Dutch theoretical
physicist and Paul Ehrenfest protégé who had studied criminology and had
previously worked at the MIT Radiation Laboratory.
Goudsmit followed
Pash to Strasbourg, began laboriously examining documents and hit the
jackpot.
He recalls the experience in a postwar memoir:
It is true that no precise information was given in these documents, but there was far more than
enough to get a view of the whole German uranium project.
We studied the papers by candlelight
for two days and nights until our eyes began to hurt....
e conclusions were unmistakable.
e
evidence at hand proved definitely that Germany had no atom bomb and was not likely to have
one in any reasonable form.2254
But paper evidence was not good enough for Groves; as far as he was
concerned, he could close the books on the German program only when he
had accounted for all the Union Minière uranium ore the Germans had
confiscated when they invaded Belgium in 1940, some 1,200 tons in all, the
only source of untraced bomb material available to them during the war
with the mines at Joachimsthal under surveillance and the Belgian Congo
cut off.
Pash had already liberated part of that supply, some 31 tons, from a
French arsenal in Toulouse where it had been diverted and secretly stored.
Moving into Germany with the Allied armies aer they crossed the Rhine
late in March he acquired a larger force of men, two armored cars mounted
with.50-caliber machine guns and four machine-gun-mounted jeeps and
began tracking the German atomic scientists themselves.
“Washington
wanted absolute proof,” Pash remembers, “that no atomic activity of which it
did not know was being carried on by the Nazis.
It also wanted to be sure
that no prominent German scientist would evade capture or fall into the
hands of the Soviet Union.” 2255 Alsos moved through Heidelberg and picked
up Walther Bothe, whose laboratory contained Germany’s only functioning
cyclotron.
Documents there pointed to Stadtilm, near Weimar, as the
location of Kurt Diebner’s laboratory.
e small town proved to have
become the central office of the German atomic research program as well,
and although Werner Heisenberg and his group from the Kaiser Wilhelm
Institutes had moved to southern Germany to escape Allied bombing and
the advancing Russian and Allied armies, there was a small amount of
uranium oxide at Stadtilm to reward Pash’s search.
Pash missed the ore rescue.
Groves’ liaison man with the British had been
watching a factory at Stassfurt, near Magdeburg in northern Germany, since
late 1944, when documents captured in Brussels indicated it might house
the balance of the Belgium ore.
By early April 1945 the Red Army had
advanced too close to that prize to leave it uninspected any longer; Groves
arranged to assemble a mixed British and American strike force led by
Lieutenant Colonel John Lansdale, Jr., the security officer who had cleared
Paul Tibbets, to move in.
e team met with the Twelh Army Group’s G-2
in Gottingen to seek approval for the Stassfurt mission; Lansdale describes
the confrontation in a report:
We outlined to him our proposal and advised him that if we found the material we were aer we
proposed to remove it and that it would be necessary that we act with the utmost secrecy and
greatest dispatch inasmuch as a meeting between the Russian armies and Allied armies apparently
would soon take place and the area in which the material appeared to be was a part of the
proposed Russian zone of occupation.
[e G-2] was very perturbed at our proposal and foresaw
all kinds of difficulties with the Russians and political repercussions at home.
Said he must see the
Commanding General.
2256
at was calm, no-nonsense Omar Bradley:
He went alone in to see General Bradley, who at that time was in conference with [the] Ninth
Army Commander within whose area Stassfurt then was.
Both of them gave unqualified approval
to our project, General Bradley being reported to have remarked “to hell with the Russians.”
On April 17, led by an infantry-division intelligence officer familiar with
the area, Lansdale and his team struck for Stassfurt:
e plant was a mess both from our bombings and from looting by the French workmen.
Aer going through mountains of paper we located the lager or inventory of papers which disclosed the
presence of the material we sought at the plant....
is ore was fortunately stored above ground.
It
was in barrels in open sided sheds and had obviously been there a long time, many of the barrels
being broken open.
Approximately 1100 tons of ore were stored there.
is was in various forms,
mostly the concentrates from Belgium and about eight tons of uranium oxide.
Lansdale instructed his group to take inventory and went off to Ninth
Army headquarters.
at organization assigned him two truck companies.
He moved on to the nearest railhead within the permanent American zone
of occupation but found the commanding officer there too busy evacuating
some ten thousand Allied prisoners of war to be able to offer more help than
half a dozen men for guard duty.
Lansdale improvised, located empty
airport hangars nearby where the ore could be stored awaiting shipment out
of Germany and arranged to have them cleared of booby traps.
en he
returned to Stassfurt:
Many of the barrels in which the material was packed were broken open and the majority of those
not broken open were in such a weakened condition that they could not stand transportation.
2257
[A British and an American officer] and I took a jeep and scouting around the country found in
one small town a paper bag factory which had a large supply of very heavy bags.
We later sent a
truck and obtained 10,000 of these.
We also discovered in a mill a quantity of wire and the
necessary implements for closing the bags.
By the evening of 19th April we had a large crew busily
engaged in repacking the material and that night the movement of the material to [the railhead]
started.
Boris Pash in the meantime continued to chase down the German atomic
scientists.
Alsos documents placed Werner Heisenberg, Otto Hahn, Carl von
Weizsäcker, Max von Laue and the others in their organization in the Black
Forest region of southwestern Germany in the resort town of Haigerloch.
2258
By late April the German front had broken and the French were moving
ahead.
Pash and his forces, which now included a battalion of combat
engineers, got word in the middle of the night and raced around Stuttgart in
their jeeps and trucks and armored cars to beat the French to Haigerloch.
ey drew German fire along the way and returned it.
In the meantime
Lansdale in London reassembled his British-American team and flew over
to follow Pash in.
e story is properly Pash’s:2259
Haigerloch is a small, picturesque town straddling the Eyach River.
As we approached it,
pillowcases, sheets, towels and other white articles attached to flagpoles, broomsticks and window
shutters flew the message of surrender....
While our engineer friends were busy consolidating the first Alsosdirected seizure of an enemy town, [Pash’s men] led teams in a rapid operation to locate Nazi research facilities.
ey
soon found an ingenious set-up that gave almost complete protection from aerial observation and
bombardment—a church atop a cliff.
Hurrying to the scene, I saw a box-like concrete entrance to a cave in the side of an 80-foot cliff
towering above the lower level of the town.
e heavy steel door was padlocked.
A paper stuck on
the door indicated the manager’s identity....
When the manager was brought to me, he tried to convince me that he was only an
accountant.
When he hesitated at my command to unlock the door, I said: “Beatson, shoot the lock
off.
If he gets in the way, shoot him.”
e manager opened the door....
In the main chamber was a concrete pit about ten feet in diameter.
Within the pit hung a
heavy metal shield covering the top of a thick metal cylinder.
e latter contained a pot-shaped
vessel, also of heavy metal, about four feet below the floor level.
Atop the vessel was a metal frame....
[A] German prisoner...
confirmed the fact that we had captured the Nazi uranium
“machine” as the Germans called it—actually an atomic pile.
Pash le Goudsmit and his several colleagues behind at Haigerloch on
April 23 and rushed to nearby Hechingen.
ere he found the German
scientists, all except Otto Hahn, whom he picked up in Tailfingen two days
later, and Werner Heisenberg, whom he located with his family at a lake
cottage in Bavaria.
e pile at Haigerloch had served for the KWI’s final round of neutron-
multiplication studies.
One and a half tons of carefully husbanded Norsk-
Hydro heavy water moderated it; its fuel consisted of 664 cubes of metallic
uranium attached to 78 chains that hung down into the water from the
metal “shield” Pash describes.
With this elegant arrangement and a central
neutron source the KWI team in March had achieved nearly sevenfold
neutron multiplication; Heisenberg had calculated at the time that a 50
percent increase in the size of the reactor would produce a sustained chain
reaction.
“e fact that the German atom bomb was not an immediate threat,”
Boris Pash writes with justifiable pride, “was probably the most significant
single piece of military intelligence developed throughout the war.
Alone,
that information was enough to justify Alsos.
”2260 But Alsos managed more:
it prevented the Soviet Union from capturing the leading German atomic
scientists and acquiring a significant volume of high-quality uranium ore.
e Belgian ore confiscated at Toulouse was already being processed
through the Oak Ridge calutrons for Little Boy.
* * *
At Los Alamos in late 1944 Otto Frisch, always resourceful at invention,
proposed a daring program of experiments.
Enriched uranium had begun
arriving on the Hill from Oak Ridge.
By compounding the metal with
hydrogen-rich material to make uranium hydride it had become possible to
approach an assembly of critical mass responsive to fast as well as slow
neutrons.
Frisch was leader of the Critical Assemblies group in G Division.
Making a critical assembly involved stacking several dozen 1½-inch bars of
hydride one at a time and measuring the increased neutron activity as the
cubical stack approached critical mass.
Usually the small bars were stacked
within a boxlike framework of larger machined bricks of beryllium tamper
to reflect back neutrons and reduce the amount of uranium required.
Dozens of these critical-assembly experiments had gone forward during
1944.
“By successively lowering the hydrogen content of the material as
more U235 became available,” the Los Alamos technical history points out,
“experience was gained with faster and faster reactions.
”2261
But it was impossible to assemble a complete critical mass by stacking
bars; such an assembly would run away, kill its sponsors with radiation and
melt down.
Frisch nearly caused a runaway reaction one day by leaning too
close to a naked assembly—he called it a Lady Godiva—that was just
subcritical, allowing the hydrogen in his body to reflect back neutrons.
“At
that moment,” he remembers, “out of the corner of my eye I saw that the
little red [monitoring] lamps had stopped flickering.
2262 ey appeared to be
glowing continuously.
e flicker had speeded up so much that it could no
longer be perceived.” Instantly Frisch swept his hand across the top of the
assembly and knocked away some of the hydride bars.
“e lamps slowed
down again to a visible flicker.” In two seconds he had received by the
generous standards of the wartime era a full day’s permissible dose of
radiation.
Despite that frightening experience, Frisch wanted to work with full
critical masses to determine by experiment what Los Alamos had so far been
able to determine only theoretically: how much uranium Little Boy would
need.
Hence his daring proposal:
e idea was that the compound of uranium-235, which by then had arrived on the site, enough to
make an explosive device, should indeed be assembled to make one, but leaving a big hole so that
the central portion was missing; that would allow enough neutrons to escape so that no chain reaction could develop.2263 But the missing portion was to be made, ready to be dropped through the hole so that for a split second there was the condition for an atomic explosion, although only
barely so.
Brilliant young Richard Feynman laughed when he heard Frisch’s plan and
named it: he said it would be like tickling the tail of a sleeping dragon.
2264
e Dragon experiment it became.
At a remote laboratory site in Omega Canyon that Fermi also used,
Frisch’s group built a ten-foot iron frame, the “guillotine,” that supported
upright aluminum guides.
e experimenters surrounded the guides at table
level with blocks of uranium hydride.
To the top of the guillotine they raised
a hydride core slug about two by six inches in size.
It would fall under the
influence of gravity, accelerating at 32 feet per second/per second.
When it
passed between the blocks it would momentarily form a critical mass.
Mixed
with hydride, the U235 would react much more slowly than pure metal
would react later in Little Boy.
But the Dragon would stir, and its dangerous
stirring would give Frisch a measure of the fit between theory and
experiment:
It was as near as we could possibly go towards starting an atomic explosion without actually being
blown up, and the results were most satisfactory.
Everything happened exactly as it should.
When
the core was dropped through the hole we got a large burst of neutrons and a temperature rise of
several degrees in that very short split second during which the chain reaction proceeded as a sort
of stifled explosion.
We worked under great pressure because the material had to be returned by a
certain date to be made into metal....2265 During those hectic weeks I worked about seventeen hours a day and slept from dawn till mid-morning.
e official Los Alamos history measures the significance of Frisch’s
Dragon-tickling:
ese experiments gave direct evidence of an explosive chain reaction.
ey gave an energy
production of up to twenty million watts, with a temperature rise in the hydride up to 2°C per
millisecond.
e strongest burst obtained produced 1015 neutrons.
e dragon is of historical
importance.
It was the first controlled nuclear reaction which was supercritical with prompt
neutrons alone.
2266
By April 1945 Oak Ridge had produced enough U235 to allow a
nearcritical assembly of pure metal without hydride dilution.
e little bars
arrived at the Omega site packed in small, heavy boxes everyone took pains
to set well apart; unpacked and unwrapped, the metal shone silver in Frisch’s
workbench light.
Gradually it oxidized, to blue and then to rich plum.
Frisch
had walked in the snow at Kungälv puzzling out the meaning of Otto Hahn’s
letters to his aunt; in the basement at Bohr’s institute in Copenhagen he had
borrowed a name from biology for the process that made these small exotic
bars deadly beyond measure; at Birmingham with Rudolf Peierls he had
toyed with a formula and had first seen clearly that no more plum-colored
metal than now lay scattered on his workbench would make a bomb that
would change the world.
At Los Alamos in Southwestern spring,
dénouement: he would assemble as near a critical mass of U235 as anyone
might ever assemble by hand and not be destroyed.
April 12, ursday, was the day Frisch completed his critical assembly
experiments with metallic U235.
e previous day Robert Oppenheimer
had written Groves the cheering news that Kistiakowsky had managed to
produce implosive compressions so smoothly symmetrical that their
numbers agreed with theoretical prediction.
April 12 in America was Friday,
April 13, in Japan, and on the night of that unlucky day B-29’s bombing
Tokyo bombed the Riken.
e wooden building housing Yoshio Nishina’s
unsuccessful gaseous thermal diffusion experiment did not immediately
burn; firemen and staff managed to extinguish the fires that threatened it.
But aer the other fires were out the building suddenly burst into flame.
It
burned to the ground and took the Japanese atomic bomb project with it.
In
Europe John Lansdale was preparing to rush to Stassfurt to confiscate what
remained of the Belgian uranium ore; when Groves heard of the success of
that adventure later in April he wrote a memorandum to George Marshall
that closed the German book:
In 1940 the German Army in Belgium confiscated and removed to Germany about 1200 tons of
uranium ore.
So long as this material remained hidden under the control of the enemy we could
not be sure but that he might be preparing to use atomic weapons.
2267
Yesterday I was notified by cable that personnel of my office had located this material near
Stassfurt, Germany and that it was now being removed to a safe place outside of Germany where it
will be under the complete control of American and British authorities.
e capture of this material, which was the bulk of uranium supplies available in Europe, would
seem to remove definitely any possibility of the Germans making use of an atomic bomb in this
war.
e day these events cluster around, April 12, saw another book closed: at
midday, in Warm Springs, Georgia, while sitting for a portrait, Franklin
Delano Roosevelt in the sixty-third year of his life was shattered by a
massive cerebral hemorrhage.
He lingered comatose through the aernoon
and died at 3:35 P.M.
He had served his nation as President for thirteen
years.
When the news of Roosevelt’s death reached Los Alamos, Oppenheimer
came out from his office onto the steps of the administration building and
spoke to the men and women who had spontaneously gathered there.
ey
grieved as Americans everywhere grieved for the loss of a national leader.
Some also worried about whether the Manhattan Project would continue.
Oppenheimer scheduled a Sunday morning memorial service that everyone
in and out of the Tech Area might attend.
“Sunday morning found the mesa deep in snow,” Philip Morrison recalls
of that day, April 15.
“A night’s fall had covered the rude textures of the
town, silenced its business, and unified the view in a so whiteness, over
which the bright sun shone, casting deep blue shadows behind every wall.
It
was no costume for mourning, but it seemed recognition of something we
needed, a gesture of consolation.
Everybody came to the theater, where
Oppie spoke very quietly for two or three minutes out of his heart and
ours.” 2268 It was Robert Oppenheimer at his best:
When, three days ago, the world had word of the death of President Roosevelt, many wept who are
unaccustomed to tears, many men and women, little enough accustomed to prayer, prayed to
God.2269 Many of us looked with deep trouble to the future; many of us felt less certain that our works would be to a good end; all of us were reminded of how precious a thing human greatness is.
We have been living through years of great evil, and of great terror.
Roosevelt has been our
President, our Commander-in-Chief and, in an old and unperverted sense, our leader.
All over the
world men have looked to him for guidance, and have seen symbolized in him their hope that the
evils of this time would not be repeated; that the terrible sacrifices which have been made, and
those that are still to be made, would lead to a world more fit for human habitation....
In the Hindu scripture, in the Bhagavad-Gita, it says, “Man is a creature whose substance is
faith.
What his faith is, he is.” e faith of Roosevelt is one that is shared by millions of men and
women in every country of the world.
For this reason it is possible to maintain the hope, for this
reason it is right that we should dedicate ourselves to the hope, that his good works will not have
ended with his death.
Vice President Harry S.
Truman of Independence, Missouri, who knew
only the bare fact of the Manhattan Project’s existence, said later that when
he heard from Eleanor Roosevelt that he must assume the Presidency in
Franklin Roosevelt’s place, “I kept thinking, ‘e lightning has struck.
e
lightning has struck!’ ” Between the ursday of Roosevelt’s death and the
Sunday of the memorial service on the Hill, Otto Frisch delivered to Robert
Oppenheimer his report on the first experimental determination of the
critical mass of pure U235.2270 Little Boy needed more than one critical
mass, but the fulfillment of that requirement was now only a matter of time.
e lightning had struck at Los Alamos as well.
PART THREE
LIFE
AND
DEATH
What will people of the future think of us?
Will they say, as Roger Williams said of some of the Massachusetts Indians, that we were wolves with the minds of men?
Will they think that we resigned our
humanity?
ey will have the right.
C.
P.
Snow
I see that as human beings we have two great ecstatic impulses in us.
One is to participate in life, which
ends in the giving of life.
e other is to avoid death, which ends tragically in the giving of death.
Life and death are in our gi, we can activate life and activate death.
Gil Elliot
18
Trinity
Within twenty-four hours of Franklin Roosevelt’s death two men told Harry
Truman about the atomic bomb.
e first was Henry Lewis Stimson, the
upright, white-haired, distinguished Secretary of War.
He spoke to the newly
sworn President following the brief cabinet meeting Truman called aer
taking the oath of office on the evening of the day Roosevelt died.
“Stimson
told me,” Truman reports in his memoirs, “that he wanted me to know about
an immense project that was under way—a project looking to the
development of a new explosive of almost unbelievable destructive power.
at was all he felt free to say at the time, and his statement le me puzzled.
It was the first bit of information that had come to me about the atomic
bomb, but he gave me no details.” 2271
Truman had known of the Manhattan Project’s existence since his
wartime Senate work as chairman of the Committee to Investigate the
National Defense Program, when he had attempted to explore the expensive
secret project’s purpose and had been rebuffed by the Secretary of War
himself.
at a senator of watchdog responsibility and bulldog tenacity
would call off an investigation into unaccounted millions of dollars in
defense-plant construction on Stimson’s word alone gives some measure of
the quality of the Secretary’s reputation.
Stimson was seventy-seven years old when Truman assumed the
Presidency.
He could remember stories his great-grandmother told him of
her childhood talks with George Washington.
He had attended Phillips
Andover when the tuition at that distinguished New England preparatory
school was sixty dollars a year and students cut their own firewood.
He had
graduated from Yale College and Harvard Law School, had served as
Secretary of War under William Howard Ta, as Governor General of the
Philippines under Calvin Coolidge, as Secretary of State under Herbert
Hoover.
Roosevelt had called him back to active service in 1940 and with
able assistance especially from George Marshall and despite insomnia and
migraines that frequently laid him low he had built and administered the
most powerful military organization in the history of the world.
He was a
man of duty and of rectitude.
“e chief lesson I have learned in a long life,”
he wrote at the end of his career, “is that the only way you can make a man
trustworthy is to trust him; and the surest way to make him untrustworthy
is to distrust him and show your distrust.” 2272 Stimson sought to apply the
lesson impartially to men and to nations.
In the spring of 1945 he was
greatly worried about the use and consequences of the atomic bomb.
e other man who spoke to Truman, on the following day, April 13, was
James Francis Byrnes, known as Jimmy, sixty-six years old, a private citizen
of South Carolina since the beginning of April but before then for three
years what Franklin Roosevelt had styled “assistant President”: Director of
Economic Stabilization and then Director of War Mobilization, with offices
in the White House.2273 While FDR ran the war and foreign affairs, that is,
Byrnes had run the country.
“Jimmy Byrnes...
came to see me,” writes
Truman of his second briefing on the atomic bomb, “and even he told me
few details, though with great solemnity he said that we were perfecting an
explosive great enough to destroy the whole world.
”2274 en or soon
aerward, before Truman met with Stimson again, Byrnes added a
significant twist to his tale: “that in his belief the bomb might well put us in a
position to dictate our own terms at the end of the war.
”2275
At that first Friday meeting Truman asked Byrnes to transcribe his
shorthand notes on the Yalta Conference, three months past, which Byrnes
had attended as one of Roosevelt’s advisers and about which Truman, merely
the Vice President then, knew little.
Yalta represented nearly all Byrnes’
direct experience of foreign affairs.
It was more than Truman had.
Under the
circumstances the new President found it sufficient and informed his
colleague that he meant to make him Secretary of State.
Byrnes did not
object.
He insisted that he be given a free hand, however, as Roosevelt had
given him in domestic affairs, and Truman agreed.
“A small, wiry, neatly made man,” a team of contemporary observers
describes Jimmy Byrnes, “with an odd, sharply angular face from which his
sharp eyes peer out with an expression of quizzical geniality.
”2276 Dean
Acheson, then an Assistant Secretary of State, thought Byrnes overconfident
and insensitive, “a vigorous extrovert, accustomed to the lusty exchange of
South Carolina politics.
”2277 Truman assayed the South Carolinian most
shrewdly a few months aer their April discussion in a private diary he
intermittently kept:
Had a long talk with my able and conniving Secretary of State.
My but he has a keen mind!
And he
is an honest man.
But all country politicians are alike.
ey are sure all other politicians are circuitous in their dealings.
When they are told the straight truth, unvarnished, it is never believed
—an asset sometimes.
2278
A politician’s politician, Byrnes had managed in his thirty-two years of
public life to serve with distinction in all three branches of the federal
government.
He was self-made from the ground up.
His father died before
he was born.
His mother learned dressmaking to survive.
Young Jimmy
found work at fourteen, his last year of formal education, in a law office, but
in lieu of classroom study one of the law partners kindly guided him
through a comprehensive reading list.
His mother in the meantime taught
him shorthand and in 1900, at twenty-one, he earned appointment as a
court reporter.
He read for the law under the judge whose circuit he
reported and passed the bar in 1904.
He ran first, in 1908, for solicitor, the
South Carolina equivalent of district attorney, and made himself known
prosecuting murderers.
More than forty-six stump debates won him election
to Congress in 1910; in 1930, aer fourteen years in the House and five years
out of office, he was elected to the Senate.
By then he was already actively
promoting Franklin Roosevelt’s approaching presidential bid.
Byrnes served
as one of the candidate’s speechwriters during the 1932 campaign and
aerward worked hard as Roosevelt’s man in the Senate to push through the
New Deal.
His reward, in 1941, was a seat on the United States Supreme
Court, which he resigned in 1942 to move to the White House to take over
operating the complicated wartime emergency program of wage and price
controls, the assistant Presidency of which Roosevelt spoke.
In 1944 everyone understood that Roosevelt’s fourth term would be his
last.
e man he selected for Vice President would therefore almost certainly
take the Democratic Party presidential nomination in 1948.
Byrnes expected
to be that man and Roosevelt encouraged him.
But the assistant President
was a conservative Democrat from the Deep South, and at the last minute
Roosevelt compromised instead on the man from Missouri, Harry S.
Truman.
“I freely admit that I was disappointed,” Byrnes writes with
understatement approaching lockjaw, “and felt hurt by President Roosevelt’s
action.
”2279 He made a point of visiting the European front with George Marshall in September 1944, in the midst of the presidential campaign;
when he returned FDR had to appeal to him formally by letter—a document
Byrnes could show around—to endorse the ticket with a speech.
Byrnes undoubtedly regarded Truman as a usurper: if not Truman but he
had been Roosevelt’s choice he would be President of the United States now.
Truman knew Byrnes’ attitude but needed the old pro badly to help him run
the country and face the world.
Hence the prize of State.
e Secretary of
State was the highest-ranking member of the cabinet and under the rules of
succession then obtaining was the officer next in line for the Presidency as
well when the Vice Presidency was vacant.
Short of the Presidency itself,
State was the most powerful office Truman had to give.
Vannevar Bush and James Bryant Conant had needed months to convince
Henry Stimson to take up consideration of the bomb’s challenge in the
postwar era.
He had not been ready in late October 1944 when Bush pressed
him for action and he had not been ready in early December when Bush
pressed him again.
By then Bush knew what he thought the problem
needed, however:
We proposed that the Secretary of War suggest to the President the establishment of a committee
or commission with the duty of preparing plans.2280 ese would include the draing of legislation and the draing of appropriate releases to be made public at the proper time....
We were all in
agreement that the State Department should now be brought in.
Stimson allowed one of his trusted aides, Harvey H.
Bundy, a Boston lawyer,
father of William P.
and McGeorge, at least to begin formulating a
membership roster and list of duties for such a committee.
But he did not
yet know even in broad outline what basic policy to recommend.
Bohr’s ideas, variously diluted, floated by that time in the Washington air.
Bohr had sought to convince the American government that only early
discussion with the Soviet Union of the mutual dangers of a nuclear arms
race could forestall such an arms race once the bomb became known.
(He
would try again in April to see Roosevelt; Felix Frankfurter and Lord
Halifax, the British ambassador, would be strolling in a Washington park
discussing Bohr’s best avenue of approach when the bells of the city’s
churches began tolling the news of the President’s death.) Apparently no one
within the executive branch was sufficiently convinced of the inevitability of
Bohr’s vision.
Stimson was as wise as any man in government, but late in
December he cautioned Roosevelt that the Russians should earn the right to
hear the baleful news:
I told him of my views as to the future of S-1 [Stimson’s code for the bomb] in connection with
Russia: that I knew they were spying on our work but had not yet gotten any real knowledge of it
and that, while I was troubled about the possible effect of keeping from them even now that work,
I believed that it was essential not to take them into our confidence until we were sure to get a real
quid pro quo from our frankness.
I said I had no illusions as to the possibility of keeping
permanently such a secret but that I did not think it was yet time to share it with Russia.
2281 He said he thought he agreed with me.
In mid-February, aer talking again to Bush, Stimson confided to his diary
what he wanted in exchange for news of the bomb.
Bohr’s conviction that
only an open world modeled in some sense on the republic of science could
answer the challenge of the bomb had dried, in Bush’s mind, to a proposal
for an international pool of scientific research.
Of such an arrangement
Stimson wrote that “it would be inadvisable to put it into full force yet, until
we had gotten all we could in Russia in the way of liberalization in exchange
for S-l.” 2282 at is, the quid pro quo Stimson thought the United States
should demand from the Soviet Union was the democratization of its
government.
What for Bohr was the inevitable outcome of a solution to the
problem of the bomb—an open world where differences in social and
political conditions would be visible to everyone and therefore under
pressure to improve—Stimson imagined should be a precondition to any
initial exchange.
Finally in mid-March Stimson talked to Roosevelt, their last meeting.
at
talk came to no useful end.
In April, with a new President in the White
House, he prepared to repeat the performance.
In the meantime the men who had advised Franklin Roosevelt were
working to convince Harry Truman of the increasing perfidy of the Soviet
Union.
Averell Harriman, the shrewd multimillionaire Ambassador to
Moscow, had rushed to Washington to brief the new President.
Truman says
Harriman told him the visit was based on “the fear that you did not
understand, as I had seen Roosevelt understand, that Stalin is breaking his
agreements.” To soen that condescension Harriman added that he feared
Truman “could not have had time to catch up with all the recent cables.” e
self-educated Missourian prided himself on how many pages of documents
he could chew through per day—he was a champion reader—and undercut
Harriman’s condescension breezily by instructing the ambassador to “keep
on sending me long messages.” 2283
Harriman told Truman they were faced with a “barbarian invasion of
Europe.
”2284 e Soviet Union, he said, meant to take over its neighbors and
install the Soviet system of secret police and state control.
“He added that he
was not pessimistic,” the President writes, “for he felt that it was possible for
us to arrive at a workable basis with the Russians.
He believed that this
would require a reconsideration of our policy and the abandonment of any
illusion that the Soviet government was likely soon to act in accordance with
the principles to which the rest of the world held in international affairs.”
Truman was concerned to convince Roosevelt’s advisers that he meant to
be decisive.
“I ended the meeting by saying, ‘I intend to be firm in my
dealings with the Soviet government.’ ”2285 Delegates were arriving in San
Francisco that April, for example, to formulate a charter for a new United
Nations to replace the old and defunct League.
Harriman asked Truman if
he would “go ahead with the world organization plans even if Russia
dropped out.” 2286 Truman remembers responding realistically that “without
Russia there would not be a world organization.” ree days later, having
heard from Stalin in the meantime and met the arriving Soviet Foreign
Minister, Vyacheslav Molotov, he retreated from realism to bluster.
“He felt
that our agreements with the Soviet Union had so far been a one-way street,”
an eyewitness recalls, “and that he could not continue; it was now or never.
He intended to go on with the plans for San Francisco and if the Russians
did not wish to join us they could go to Hell.” 2287
Stimson argued for patience.
“In the big military matters,” Truman reports
him saying, “the Soviet government had kept its word and the military
authorities of the United States had come to count on it.
In fact...
they had
oen done better than they had promised.” 2288 Although George Marshall
seconded Stimson’s argument and Truman could not have had two more
reliable witnesses, it was not counsel the new and untried President wanted
to hear.
Marshall added a crucial justification that Truman took to heart:
He said from the military point of view the situation in Europe was secure but that we hoped for
Soviet participation in the war against Japan at a time when it would be useful to us.
e Russians
had it within their power to delay their entry into the Far Eastern war until we had done all the
dirty work.
He was inclined to agree with Mr.
Stimson that the possibility of a break with Russia was very serious.2289
Truman could hardly tell the Russians to go to hell if he needed them to
finish the Pacific war.
Marshall’s justification for patience meant Stalin had
the President over a barrel.
It was not an arrangement Harry Truman
intended to perpetuate.
He let Molotov know.
ey had sparred diplomatically at their first
meeting; now the President attacked.
e issue was the composition of the
postwar government of Poland.
Molotov discussed various formulas, all
favoring Soviet dominance.
Truman demanded the free elections that he
understood had been agreed upon at Yalta: “I replied sharply that an
agreement had been reached on Poland and that there was only one thing to
do, and that was for Marshal Stalin to carry out that agreement in
accordance with his word.
”2290 Molotov tried again.
Truman replied sharply
again, repeating his previous demand.
Molotov hedged once more.
Truman
proceeded to lay him low: “I expressed once more the desire of the United
States for friendship with Russia, but I wanted it clearly understood that this
could be only on a basis of the mutual observation of agreements and not on
the basis of a one-way street.” ose are hardly fighting words; Molotov’s
reaction suggests that the President spoke more pungently at the time:
“I have never been talked to like that in my life,” Molotov said.
I told him, “Carry out your agreements and you won’t get talked to like that.”
If Truman felt better for the exchange, it disturbed Stimson.
e new
President had acted without knowledge of the bomb and its potentially
fateful consequences.
It was time and past time for a full briefing.
Truman agreed to meet with Stimson at noon on Wednesday, April 25.
e President was scheduled to address the opening session of the United
Nations conference in San Francisco by radio that evening.
One more
conditioning incident intervened; on Tuesday he received a communication
from Joseph Stalin, “one of the most revealing and disquieting messages to
reach me during my first days in the White House.” 2291, 2292 Molotov had reported Truman’s tough talk to the Soviet Premier.
Stalin replied in kind.
Poland bordered on the Soviet Union, he wrote, not on Great Britain or the
United States.
“e question [of] Poland had the same meaning for the
security of the Soviet Union as the question [of] Belgium and Greece for the
security of Great Britain”—but “the Soviet Union was not consulted when
those governments were being established there” following the Allied
liberation.
e “blood of the Soviet people abundantly shed on the fields of
Poland in the name of the liberation of Poland” demanded a Polish
government friendly to Russia.
And finally:
I am ready to fulfill your request and do everything possible to reach a harmonious solution.
But
you demand too much of me.
In other words, you demand that I renounce the interests of security
of the Soviet Union, but I cannot turn against my country.
With this blunt challenge on his mind Truman received his Secretary of War.
Stimson had brought Groves along for technical backup but le him
waiting in an outer office while he discussed issues of general policy.
He
began dramatically, reading from a memorandum:2293
Within four months we shall in all probability have completed the most terrible weapon ever
known in human history, one bomb of which could destroy a whole city.
We had shared the development with the British, Stimson continued, but we
controlled the factories that made the explosive material “and no other
nation could reach this position for some years.” It was certain that we
would not enjoy a monopoly forever, and “probably the only nation which
could enter into production within the next few years is Russia.” e world
“in its present state of moral advancement compared with its technical
development,” the Secretary of War continued quaintly, “would be
eventually at the mercy of such a weapon.
In other words, modern
civilization might be completely destroyed.”
Stimson emphasized what John Anderson had emphasized to Churchill
the year before: that founding a “world peace organization” while the bomb
was still a secret “would seem to be unrealistic”:
No system of control heretofore considered would be adequate to control this menace.
Both inside
any particular country and between the nations of the world, the control of this weapon will
undoubtedly be a matter of the greatest difficulty and would involve such thorough-going rights of
inspection and internal controls as we have never heretofore contemplated.
at brought Stimson to the crucial point:
Furthermore, in the light of our present position with reference to this weapon, the question of sharing it with other nations and, if so shared, upon what terms, becomes a primary question of
our foreign relations.
Bohr had proposed to inform other nations of the common dangers of a
nuclear arms race.
At the hands of Stimson and his advisers that sensible
proposal had dried to the notion that the issue was sharing the weapon
itself.
As Commander in Chief, as a veteran of the First World War, as a man
of common sense, Truman must have wondered what on earth his Secretary
of War was talking about, especially when Stimson added that “a certain
moral responsibility” followed from American leadership in nuclear
technology which the nation could not shirk “without very serious
responsibility for any disaster to civilization which it would further.” Was the
United States morally obligated to give away a devastating new weapon of
war?
Now Stimson called in Groves.
e general brought with him a report on
the status of the Manhattan Project that he had presented to the Secretary of
War two days earlier.
Both Stimson and Groves insisted Truman read the
document while they waited.
e President was restive.
He had a
threatening note from Stalin to deal with.
He had to prepare to open the
United Nations conference even though Stimson had just informed him that
allowing the conference to proceed in ignorance of the bomb was a sham.
A
scene of darkening comedy followed as the proud man who had challenged
Averell Harriman to keep sending him long messages tried to avoid public
instruction in the minutiae of a secret project he had fought doggedly as a
senator to investigate.
Groves misunderstood completely:
Mr.
Truman did not like to read long reports.
is report was not long, considering the size of the
project.
It was about twenty-four pages and he would constantly interrupt his reading to say, “Why,
I don’t like to read papers.” And Mr.
Stimson and I would reply: “Well we can’t tell you this in any
more concise language.
is is a big project.” For example, we discussed our relations with the
British in about four or five lines.
It was that much condensed.
We had to explain all the processes
and we might just say what they were and that was about all.
2294
Aer the reading of the lesson, Groves notes, “a great deal of emphasis was
placed on foreign relations and particularly on the Russian situation”—
Truman reverting to his immediate problems.
He “made it very definite,”
Groves adds for the record, “that he was in entire agreement with the
necessity for the project.” 2295
e final point in Stimson’s memorandum was the proposal Bush and
Conant had initiated to establish what Stimson called “a select committee...
for recommending action to the Executive and legislative branches of our
government.” Truman approved.
In his memoirs the President describes his meeting with Stimson and
Groves with tact and perhaps even a measure of private humor: “I listened
with absorbed interest, for Stimson was a man of great wisdom and
foresight.
He went into considerable detail in describing the nature and the
power of the projected weapon....
Byrnes had already told me that the
weapon might be so powerful as to be capable of wiping out entire cities and
killing people on an unprecedented scale.” at was when Byrnes had
crowed that the new bombs might allow the United States to dictate its own
terms at the end of the war.2296 “Stimson, on the other hand, seemed at least
as much concerned with the role of the atomic bomb in the shaping of
history as in its capacity to shorten this war....
I thanked him for his
enlightening presentation of this awesome subject, and as I saw him to the
door I felt how fortunate the country was to have so able and so wise a man
in its service.” High praise, but the President was not sufficiently impressed
at the outset with Stimson and Harriman to invite either man to accompany
him to the next conference of the Big ree.
Both found it necessary, when
the time came, to invite themselves.
Jimmy Byrnes went at the President’s
invitation and sat at the President’s right hand.
Discussion between Truman and his various advisers was one level of
discourse in the spring of 1945 on the uses of the atomic bomb.
Another was
joined two days aer Stimson and Groves briefed the President when a
Target Committee under Groves’ authority met for the first time in Lauris
Norstad’s conference room at the Pentagon.
Brigadier General omas F.
Farrell, who would represent the Manhattan Project as Groves’ deputy to the
Pacific Command, chaired the committee; besides Farrell it counted two
other Air Force officers—a colonel and a major—and five scientists,
including John von Neumann and British physicist William G.
Penney.
Groves opened the meeting with a variant of his usual speech to Manhattan
Project working groups: how important their duty was, how secret it must
be kept.
He had already discussed targets with the Military Policy
Committee and now informed his Target Committee that it should propose
no more than four.
2297
Farrell laid down the basics: B-29 range for such important missions no
more than 1,500 miles; visual bombing essential so that these untried and
valuable bombs could be aimed with certainty and their effects
photographed; probable targets “urban or industrial Japanese areas” in July,
August or September; each mission to be given one primary and two
alternate targets with spotter planes sent ahead to confirm visibility.
Most of the first meeting was devoted to worrying about the Japanese
weather.
Aer lunch the committee brought in the Twentieth Air Force’s top
meteorologist, who told them that June was the worst weather month in
Japan; “a little improvement is present in July; a little bit better weather is
present in August; September weather is bad.” January was the best month,
but no one intended to wait that long.
e meteorologist said he could
forecast a good day for bombing operations only twenty-four hours ahead,
but he could give two days’ notice of bad weather.
He suggested they station
submarines near the target areas to radio back weather readings.
Later in the aernoon they began considering targets.
Groves had
extended Farrell’s guidelines:
I had set as the governing factor that the targets chosen should be places the bombing of which
would most adversely affect the will of the Japanese people to continue the war.2298 Beyond that, they should be military in nature, consisting either of important headquarters or troop
concentrations, or centers of production of military equipment and supplies.
To enable us to assess
accurately the effects of the bomb, the targets should not have been previously damaged by air
raids.
It was also desirable that the first target be of such size that the damage would be confined
within it, so that we could more definitely determine the power of the bomb.
But such pristine targets had already become scarce in Japan.
If the first
choice the Target Committee identified at its first meeting was hardly big
enough to confine the potential damage, it was the best the enemy had le to
offer:
Hiroshima is the largest untouched target not on the 21st Bomber Command priority list.
Consideration should be given to this city.
“Tokyo,” the committee notes continue, “is a possibility but it is now
practically all bombed and burned out and is practically rubble with only
the palace grounds le standing.
Consideration is only possible here.”
e Target Committee did not yet fully understand the level of authority it
commanded.
With a few words to Groves it could exempt a Japanese city
from Curtis LeMay’s relentless firebombing, preserving it through spring
mornings of cherry blossoms and summer nights of wild monsoons for a
more historic fate.
e committee thought it took second priority behind
LeMay rather than first priority ahead, and in emphasizing these mistaken
priorities the colonel who reviewed the Twentieth Air Force’s bombing
directive for the committee revealed what the United States’ policy in Japan
in all its deadly ambiguity had become:
It should be remembered that in our selection of any target, the 20th Air Force is operating
primarily to laying waste all the main Japanese cities, and that they do not propose to save some
important primary target for us if it interferes with the operation of the war from their point of
view.
eir existing procedure has been to bomb the hell out of Tokyo, bomb the aircra,
manufacturing and assembly plants, engine plants and in general paralyze the aircra industry so
as to eliminate opposition to the 20th Air Force operations.
e 20th Air Force is systematically
bombing out the following cities with the prime purpose in mind of not leaving one stone lying on
another:
Tokyo, Yokohama, Nagoya, Osaka, Kyoto,
Kobe, Yawata & Nagasaki.
If the Japanese were prepared to eat stones, the Americans were prepared to
supply them.
e colonel also advised that the Twentieth Air Force planned to increase
its delivery of conventional bombs steadily until it was dropping 100,000
tons a month by the end of 1945.
e group decided to study seventeen targets including Tokyo Bay,
Yokohama, Nagoya, Osaka, Kobe, Hiroshima, Kokura, Fukuoka, Nagasaki
and Sasebo.
Targets already destroyed would be culled from the list.
e
weather people would review weather reports.
Penney would consider “the
size of the bomb burst, the amount of damage expected, and the ultimate
distance at which people would be killed.” Von Neumann would be
responsible for computations.
Adjourning its initial meeting the Target
Committee planned to meet again in mid-May in Robert Oppenheimer’s
office at Los Alamos.
A third level of discourse on the uses of the bomb revealed itself as Henry
Stimson assembled the committee that Bush and Conant had proposed to
him and he had proposed in turn to the President.
On May 1, the day
German radio announced the suicide of Adolf Hitler in the ruins of Berlin,
George L.
Harrison, a special Stimson consultant and the president of the
New York Life Insurance Company, prepared for the Secretary of War an
entirely civilian committee roster consisting of Stimson as chairman, Bush,
Conant, MIT president Karl Compton, Assistant Secretary of State William
L.
Clayton, Undersecretary of the Navy Ralph A.
Bard and a special
representative of the President whom the President might choose.
Stimson
modified the list to include Harrison as his alternate and carried it to
Truman for approval on May 2.
Truman agreed and Stimson apparently
assumed his interest in the project, but the President significantly did not
even bother to name his own man to the list.
Stimson wrote in his diary that
night:2299
e President accepted the present members of the committee and said that they would be
sufficient even without a personal representative of himself.
I said I should prefer to have such a
representative and suggested that he should be a man (a) with whom the President had close
personal relations and (b) who was able to keep his mouth shut.2300
Truman had not yet announced his intention to appoint Byrnes Secretary
of State because the holdover Secretary, Edward R.
Stettinius, Jr., was
heading the United States delegation to the United Nations in San Francisco
and the President did not want to undercut his authority there.
But word of
the forthcoming appointment had diffused through Washington.
Acting on
it, Harrison suggested that Stimson propose Byrnes.
On May 3 Stimson did,
“and late in the day the President called me up himself and said that he had
heard of my suggestion and it was fine.
He had already called up Byrnes
down in South Carolina and Byrnes had accepted.” 2301 Bundy and Harrison,
Stimson told his diary, “were tickled to death.” 2302 ey thought their
committee had acquired a second powerful sponsor.
In fact they had just
welcomed a cowbird into their nest.
Stimson sent out invitations the next day.
He proposed calling his new
group the Interim Committee to avoid appearing to usurp congressional
prerogatives: “when secrecy is no longer required,” he explained to the
prospective members, “Congress might wish to appoint a permanent Post
War Commission.
”2303 He set the first informal meeting of the Interim
Committee for May 9.
e membership would assemble in the wake of momentous change.
e
war in Europe had finally ground to an end.
Supreme Allied Commander
Dwight D.
Eisenhower celebrated the victory on national radio the evening
of Tuesday, May 8, 1945, V-E Day:
I have the rare privilege of speaking for a victorious army of almost five million fighting men.
ey, and the women who have so ably assisted them, constitute the Allied Expeditionary Force that has
liberated western Europe.
ey have destroyed or captured enemy armies totalling more than their
own strength, and swept triumphantly forward over the hundreds of miles separating Cherbourg
from Lübeck, Leipzig and Munich....
2304
ese startling successes have not been bought without sorrow and suffering.
In this eater
alone 80,000 Americans and comparable numbers among their Allies, have had their lives cut
short that the rest of us might live in the sunlight of freedom....
But, at last, this part of the job is done.
No more will there flow from this eater to the United
States those doleful lists of death and loss that have brought so much sorrow to American homes.
e sounds of battle have faded from the European scene.
Eisenhower had watched Colonel General Alfried Jodl sign the act of
military surrender in a schoolroom in Rheims—the temporary war room of
the Supreme Headquarters Allied Expeditionary Force—in the early
morning hours of May 7.
Eisenhower’s aides had attempted then to dra a
suitably eloquent message to the Combined Chiefs reporting the official
surrender.
“I tried one myself,” Eisenhower’s chief of staff Walter Bedell
Smith remembers, “and like all my associates, groped for resounding phrases
as fitting accolades to the Great Crusade and indicative of our dedication to
the great task just accomplished.” 2305 e Supreme Commander listened
quietly for a time, thanked everyone for trying and dictated his own
unadorned report:
e mission of this Allied force was fulfilled at 0241, local time, May 7th, 1945.2306
Better to be brief, better than resounding phrases.
Twenty million Soviet
soldiers and civilians died of privation or in battle in the Second World War.
Eight million British and Europeans died or were killed and another five
million Germans.
e Nazis murdered six million Jews in ghettos and
concentration camps.
Manmade death had ended thirty-nine million human
lives prematurely; for the second time in half a century Europe had become
a charnel house.
2307
ere remained the brutal conflict Japan had begun in the Pacific and
refused despite her increasing destruction to end by unconditional
surrender.
Officially Byrnes was retired to South Carolina.
In fact he was visiting
Washington surreptitiously, absorbing detailed evening briefings by State
Department division chiefs at his apartment at the Shoreham Hotel.
On the
aernoon of V-E Day he spent two hours closeted alone with Stimson.
en
Harrison, Bundy and Groves joined them.
“We all discussed the function of
the proposed Interim Committee,” Stimson records.
2308, 2309 “During the meeting it became very evident what a tremendous help Byrnes would be as
a member of the committee.”
e next morning the Interim Committee met for the first time in
Stimson’s office.
e gathering was preliminary, to fill in Byrnes, State’s
Clayton and the Navy’s Bard on the basic facts, but Stimson made a point of
introducing the former assistant President as Truman’s personal
representative.
e membership was thus put on notice that Byrnes enjoyed
special status and that his words carried extra weight.
e committee recognized that the scientists working on the atomic bomb
might have useful advice to offer and created a Scientific Panel adjunct.
Bush
and Conant put their heads together and recommended Arthur Compton,
Ernest Lawrence, Robert Oppenheimer and Enrico Fermi for appointment.
Between the first and second meetings of the Interim Committee its
Doppelgänger, the Target Committee, met again for two days, May 10 and 11,
at Los Alamos.
Added to the full committee as advisers were Oppenheimer,
Parsons, Tolman and Norman Ramsey and for part of the deliberations
Hans Bethe and Robert Brode.
Oppenheimer took control by devising and
presenting a thorough agenda:
A.
Height of Detonation2310
B.
Report on Weather and Operations
C.
Gadget Jettisoning and Landing
D.
Status of Targets
E.
Psychological Factors in Target Selection
F.
Use Against Military Objectives
G.
Radiological Effects
H.
Coordinated Air Operations
I.
Rehearsals
J.
Operating Requirements for Safety of Airplanes
K.
Coordination with 21st [Bomber Command] Program
Detonation height determined how large an area would be damaged by
blast and depended crucially on yield.
A bomb detonated too high would
expend its energy blasting thin air; a bomb detonated too low would expend
its energy excavating a crater.
It was better to be low than high, the
committee minutes explain: “e bomb can be detonated as much as 40%
below the optimum with a reduction of 24% in area of damage whereas a
detonation [only] 14% above the optimum will cause the same loss in area.”
e discussion demonstrates how uncertain Los Alamos still was of bomb
yield.
Bethe estimated a yield range for Little Boy of 5,000 to 15,000 tons
TNT equivalent.
Fat Man, the implosion bomb, was anybody’s guess: 700,
2,000, 5,000 tons?
“With the present information the fuse would be set at
2,000 tons equivalent but fusing for the other values should be available at
the time of final delivery....
Trinity data will be used for this gadget.”
e scientists reported and the committee agreed that in an emergency a
B-29 in good condition could return to base with a bomb.
“It should make a
normal landing with the greatest possible care....
e chances of [a] crash
initiating a high order [i.e., nuclear] explosion are...
sufficiently small [as to
be] a justifiable risk.” Fat Man could even survive jettisoning into shallow
water.
Little Boy was less forgiving.
Since the gun bomb contained more
than two critical masses of U235, seawater leaking into its casing could
moderate stray neutrons sufficiently to initiate a destructive slow-neutron
chain reaction.
e alternative, jettisoning Little Boy onto land, might loose
the U235 bullet down the barrel into the target core and set off a nuclear
explosion.
For temperamental Little Boy, the minutes note, unluckily for the
aircrew, “the best emergency procedure that has so far been proposed is...
the removal of the gun powder from the gun and the execution of a crash
landing.”
Target selection had advanced.
e committee had refined its
qualifications to three: “important targets in a large urban area of more than
three miles diameter” that were “capable of being damaged effectively by
blast” and were “likely to be unattacked by next August.” e Air Force had
agreed to reserve five such targets for atomic bombing.
ese included:
(1) Kyoto—is target is an urban industrial area with a population of
1,000,000.
It is the former capital of Japan and many people and
industries are now being moved there as other areas are being
destroyed.
From the psychological point of view there is the
advantage that Kyoto is an intellectual center for Japan and the
people there are more apt to appreciate the significance of such a
weapon as the gadget....
(2) Hiroshima—is is an important army depot and port of
embarkation in the middle of an urban industrial area.
It is a good
radar target and it is such a size that a large part of the city could be
extensively damaged.
ere are adjacent hills which are likely to
produce a focusing effect which would considerably increase the
blast damage.
Due to rivers it is not a good incendiary target.
e other three targets proposed were Yokohama, Kokura Arsenal and
Niigata.
An unsung enthusiast on the committee suggested a spectacular
sixth target for consideration, but wiser heads prevailed: “e possibility of
bombing the Emperor’s palace was discussed.
It was agreed that we should
not recommend it but that any action for this bombing should come from
authorities on military policy.”
So the Target Committee sitting in Oppenheimer’s office at Los Alamos
under the modified Lincoln quotation that Oppenheimer had posted on the
wall—THIS WORLD CANNOT ENDURE HALF SLAVE AND HALF FREE—remanded four
targets to further study: Kyoto, Hiroshima, Yokohama and Kokura Arsenal.
e committee and its Los Alamos consultants were not unmindful of the
radiation effects of the atomic bomb—its most significant difference in effect
from conventional high explosives—but worried more about radiation
danger to American aircrews than to the Japanese.
“Dr.
Oppenheimer
presented a memo he had prepared on the radiological effect of the
gadget....
e basic recommendations of this memo are (1) for radiological
reasons no aircra should be closer than 2 ½ miles to the point of detonation
(for blast reasons the distance should be greater) and (2) aircra must avoid
the cloud of radio-active materials.”
Since the expected yields of the bombs under discussion made them
something less than city-busters, the Target Committee considered
following Little Boy and Fat Man with conventional incendiary raids.
Radioactive clouds that might endanger LeMay’s follow-up crews worried
the targeters, though they thought an incendiary raid delayed one day aer
an atomic bombing might be safe and “quite effective.”
With a better sense for having visited Los Alamos of the weapons it was
targeting, the Target Committee scheduled its next meeting for May 28 at
the Pentagon.
Vannevar Bush thought the second Interim Committee meeting on May
14 produced “very frank discussions.” e group, he decided, was “an
excellent one.
”2311 ese judgments he passed along to Conant, who had
been unable to attend.
Stimson won approval of the Scientific Panel as
constituted and discussed the possibility of assembling a similar group of
industrialists.
As his agenda noted, such a group would “advise of [the]
likelihood of other nations repeating what our industry has done”—that is,
whether other nations could build the vast, innovative industrial plant
necessary to produce atomic bombs.
2312
at May Monday morning the committee received copies of Bush’s and
Conant’s September 30, 1944, memorandum to Stimson, the discussion
framed on Bohr’s ideas of the free exchange of scientific information and
inspection not only of laboratories throughout the world but also of military
installations.
Bush promptly hedged his commitment to so open a world:
I...
said that while we made the memorandum very explicit, that it certainly did not indicate that
we were irrevocably committed to any definite line of action but rather felt that we ought to express
our ideas early in order that there might be discussion as [a] result of which we might indeed change our thoughts as we studied into the subject further, and I said also that we would
undoubtedly write the memorandum a little differently today due to the lapse of time since last
September.
2313
At the end of the meeting Byrnes took his copy along and studied it with
interest.
2314
e Secretary of State-designate was learning fast.
When the Interim
Committee met again on Friday, May 18, with Groves sitting in, Byrnes
brought up the Bush-Conant memorandum as soon as dra press releases
announcing the dropping of the first atomic bomb on Japan had been
reviewed.
It was Bush’s turn to be absent; Conant passed along the news:
Mr.
Byrnes spent considerable time discussing our memorandum of last fall, which he had read
carefully and with which he was much impressed.
It apparently stimulated his thinking (which was
all that we had originally desired I imagine).
He was particularly impressed with our statement that
the Russians might catch up in three to four years.
is premise was violently opposed by the
General [i.e., Groves], who felt that twenty years was a much better figure....
e General is basing his long estimate on a very poor view of Russian ability, which I think is a highly unsafe
assumption....
ere was some discussion about the implications of a time interval as short as four years and
various international problems were discussed, particularly the question of whether or not the
President should tell the Russians of the existence of the weapon aer the July test.
Bohr’s proposal to enlist the Soviet Union in discussions before the atomic
bomb became a reality here slips to the question of whether or not to tell the
Soviets the bare facts aer the first bomb had been tested but before the
second was dropped on Japan.
Byrnes thought the answer to that question
might depend on how quickly the USSR could duplicate the American
accomplishment.
e Interim Committee’s recording secretary, 2nd
Lieutenant R.
Gordon Arneson, remembered aer the war of this
confrontation that “Mr.
Byrnes felt that this point was a very important
one.” 2315 e veteran of House and Senate cloakrooms was at least as
concerned as Henry Stimson to extract a quid pro quo for any exchange of
information, as Conant’s next comment to Bush demonstrates:
is question [i.e., whether or not to tell the Russians about the atomic bomb before using it on
Japan] led to the review of the Quebec Agreement which was shown once more to Mr.
Byrnes.
He
asked the General what we had got in exchange, and the General replied only the arrangements
controlling the Belgium-Congo [sic]....
Mr.
Byrnes made short work of this line of argument.2316
e Quebec Agreement of 1943 renewed the partnership of the United
States and Great Britain in the nuclear enterprise; Groves was justifying it as
an exchange for British help in securing the Union Minière’s agreement to
sell the two nations all its uranium ore.
e British-American relation was
built on deeper foundations than that, and Conant moved quickly to limit
the damage of Groves’ blunder:
Some of us then pointed out the historic background and [that] our connection with England
flowed from the original agreement as to the complete exchange of scientific information....
I can
foresee a great deal of trouble on this front.
It was interesting that Mr.
Byrnes felt that Congress
would be most curious about this phase of the matter.2317
If Byrnes had begun his service on the Interim Committee respecting the
men who had carried the Manhattan Project forward, he must have
conceived less respect for them now.
Both Stimson and Bush, Conant told
Byrnes, had talked to Churchill in Quebec.
2318 If, as it seemed, they could be
conned by the British into giving away the secrets of the bomb—whatever
Byrnes imagined those might be—for the price of a few tons of uranium ore,
how much was their judgment worth?
Why give away something so
stupendous as the bomb unless you got something equally stupendous in
return?
Byrnes believed international relations worked like domestic
politics.
e bomb was power, newly minted, and power was to politics as
money was to banking, a medium of enriching exchange.
Only naïfs and
fools gave it away.
Enter Leo Szilard.
As the man who had thought longer and harder than anyone else about
the consequences of the chain reaction, Szilard had chafed at his continuing
exile from the high councils of government.
Another politically active Met
Lab scientist, Eugene Rabinowitch, a younger man, confirms “the feeling
which was certainly shared...
by others that we were surrounded by a kind
of soundproof wall so that you could write to Washington or go to
Washington and talk to somebody but you never got any reaction back.” 2319
With the successful operation of the production reactors and separation
plants at Hanford the work of the Met Lab had slowed; Compton’s people,
Szilard particularly, found time to think about the future.
Szilard says he
began to examine “the wisdom of testing bombs and using bombs.” 2320
Rabinowitch remembers “many hours spent walking up and down the
Midway [the wide World’s Fair sward south of the University of Chicago
main campus] with Leo Szilard and arguing about these questions and about
what can be done.
I remember sleepless nights.
”2321
ere was no point in talking to Groves, Szilard reasoned in March 1945,
nor to Bush or Conant for that matter.
Secrecy barred discussion with
middle-level authorities.
“e only man with whom we were sure we would
be entitled to communicate,” Szilard recalls, “was the President.
”2322 He
prepared a memorandum for Franklin Roosevelt and traveled to Princeton
to enlist once again the durable services of Albert Einstein.
Except for some minor theoretical calculations for the Navy, Einstein had
been excluded from wartime nuclear development.
Bush explained why to
the director of the Institute for Advanced Study early in the war:
I am not at all sure that if I place Einstein in entire contact with his subject he would not discuss it
in a way that it should not be discussed....
I wish very much that I could place the whole thing
before him...
but this is utterly impossible in view of the attitude of people here in Washington
who have studied into his whole history.2323
e great theoretician whose letter to Roosevelt helped alert the United
States government to the possibility of an atomic bomb was thus spared by
concern for security and by hostility to his earlier outspoken politics—his
pacifism and probably also his Zionism—from contributing to that weapon’s
development.
Szilard could not show Einstein his memorandum.
He told his
old friend simply that there was trouble ahead and asked for a letter of
introduction to the President.
Einstein complied.
From Chicago Szilard approached Roosevelt through his wife.
Eleanor
Roosevelt agreed to see him on May 8 to pursue the matter.
us fortified,
he wandered to Arthur Compton’s office to confess his out-of-channel sins.
Compton surprised him by cheering him on.
“Elated by finding no
resistance where I expected resistance,” Szilard reports, “I went back to my
office.
2324 I hadn’t been in my office for five minutes when there was a knock
on the door and Compton’s assistant came in, telling me that he had just
heard over the radio that President Roosevelt had died....
“So for a number of days I was at a complete loss for what to do,” Szilard
goes on.
He needed a new avenue of approach.
Eventually it occurred to him
that a project as large as the Met Lab probably employed someone from
Kansas City, Missouri, Harry Truman’s original political base.
He found a
young mathematician named Albert Cahn who had worked for Kansas City
boss Tom Pendergast’s political machine to earn money for graduate school.
Cahn and Szilard traveled to Kansas City later that month, dazzled
Pendergast’s hoodlum elite with who knows what Szilardian tale “and three
days later we had an appointment at the White House.”
Truman’s appointments secretary, Matthew Connelly, barred the door.
Aer he read the Einstein letter and the memorandum he relaxed.
“I see
now,” Szilard remembers him saying, “this is a serious matter.
At first I was a
little suspicious, because the appointment came through Kansas City.” 2325
Truman had guessed the subject of Szilard’s concern.
At the President’s
direction Connelly sent the wandering Hungarian to Spartansburg, South
Carolina, to talk to a private citizen named Jimmy Byrnes.
A University of Chicago dean, a scientist named Walter Bartky, had
accompanied Szilard to Washington.
For added authority Szilard enlisted
Nobel laureate Harold Urey and the three men boarded the overnight train
south.
Compartmentalization was working: “We did not quite understand
why we were sent by the President to see James Byrnes....
Was he to...
be
the man in charge of the uranium work aer the war, or what?
We did not
know.
”2326 Truman had alerted Byrnes that the delegation was on its way.
e South Carolinian received it warily at his home.
He read the letter from
Einstein first—“I have much confidence in [Szilard’s] judgment,” the
theoretician of relativity testified—then turned to the memorandum.
2327,
2328
It was a prescient document.
It argued that in preparing to test and then
use atomic bombs the United States was “moving along a road leading to the
destruction of the strong position [the nation] hitherto occupied in the
world.” Szilard was referring not to a moral advantage but to an industrial: as
he wrote elsewhere that spring, U.S.
military strength was “essentially due to
the fact that the United States could outproduce every other country in
heavy armaments.” 2329 When other countries acquired nuclear weapons, as
they would in “just a few years,” that advantage would be lost: “Perhaps the
greatest immediate danger which faces us is the probability that our
‘demonstration’ of atomic bombs will precipitate a race in the production of
these devices between the United States and Russia.”
Much of the rest of the memorandum asked the sort of questions the
Interim Committee was also asking about international controls versus
attempting to maintain an American monopoly.
But Szilard echoed Bohr in
pleading for what no one among the national leaders concerned with the
problem seemed able to grasp, that “these decisions ought to be based not on
the present evidence relating to atomic bombs, but rather on the situation
which can be expected to confront us in this respect a few years from now.”
By present evidence the bombs were modest and the United States held
them in monopoly; the difficulty was deciding what the future would bring.
Szilard first offended Byrnes in his memorandum by concluding that “this
situation can be evaluated only by men who have first-hand knowledge of
the facts involved, that is, by the small group of scientists who are actively
engaged in this work.” Having thus informed Byrnes that he thought him
unqualified, Szilard then proceeded to tell him how his inadequacies might
be corrected:
If there were in existence a small subcommittee of the Cabinet (having as its members the
Secretary of War, either the Secretary of Commerce or the Secretary of the Interior, a
representative of the State Department, and a representative of the President, acting as the
secretary of the Committee), the scientists could then submit to such a committee their recommendations.
It was H.
G.
Wells’ Open Conspiracy emerging again into the light; it
amused Byrnes, a man who had climbed to the top across forty-five years of
hard political service, not at all:
Szilard complained that he and some of his associates did not know enough about the policy of the
government with regard to the use of the bomb.
He felt that scientists, including himself, should
discuss the matter with the Cabinet, which I did not feel desirable.
His general demeanor and his
desire to participate in policy making made an unfavorable impression on me.
2330
Byrnes proceeded to demonstrate the dangers of a lack of firsthand
knowledge, Szilard remembers:
When I spoke of my concern that Russia might become an atomic power, and might become an
atomic power soon, if we demonstrated the power of the bomb and if we used it against Japan, his
reply was, “General Groves tells me there is no uranium in Russia.
”2331
So Szilard explained to Byrnes what Groves, busy buying up the world
supply of high-grade ore, apparently did not understand: that high-grade
deposits are necessary for the extraction of so rare an element as radium but
that low-grade ores, which undoubtedly existed in the Soviet Union, were
entirely satisfactory where so abundant an element as uranium was
concerned.
To Szilard’s argument that using the atomic bomb, even testing the atomic
bomb, would be unwise because it would disclose that the weapon existed,
Byrnes took a turn at teaching the physicist a lesson in domestic politics:
He said we had spent two billion dollars on developing the bomb, and Congress would want to
know what we had got for the money spent.
He said, “How would you get Congress to appropriate
money for atomic energy research if you do not show results for the money which has been spent
already?” 2332
But Byrnes’ most dangerous misunderstanding from Szilard’s point of
view was his reading of the Soviet Union:
Byrnes thought that the war would be over in about six months....
He was concerned about
Russia’s postwar behavior.
Russian troops had moved into Hungary and Rumania, and Byrnes
thought it would be very difficult to persuade Russia to withdraw her troops from these countries,
that Russia might be more manageable if impressed by American military might, and that a
demonstration of the bomb might impress Russia.
I shared Byrnes’ concern about Russia’s
throwing around her weight in the postwar period, but I was completely flabbergasted by the assumption that rattling the bomb might make Russia more manageable.
2333
Shadowed by one of Groves’ ubiquitous security agents, the three
discouraged men caught the next train back to Washington.
ere on the same day the Target Committee was meeting, this time with
Paul Tibbets as well as Tolman and Parsons on hand.2334 Much of the
discussion concerned Tibbets’ training program for the 509th Composite
Group.
He had sent his best crews to Cuba for six weeks to give them radar
experience and flying time over water.
“On load and distance tests,” the
committee minutes report, “Col.
Tibbets stated crews had taken off at
135,000 lbs.
gross load, flown 4300 miles with 10,000 lb.
bomb load, bombed
from 32,000 .
and returned to base with 900 gallons of fuel.
is is in
excess of the expected target run and further tests will reduce the loading to
reach the S.O.P.
[standard operating procedure] of 500 gallons of fuel on
return.” e 509th was in the process of staging out to Tinian.
Pumpkin
production was increasing; nineteen had been shipped to Wendover and
some of them dropped.
LeMay was also keeping busy.
“e 3 reserved targets for the first unit of
this project were announced.
With current and prospective rate of
[Twentieth Air Force] H.E.
bombing, it is expected to complete strategic
bombing of Japan by 1 Jan 46 so availability of future targets will be a
problem.” If the Manhattan Project did not hurry, that is, there would be no
cities le in Japan to bomb.
Kyoto, Hiroshima and Niigata were the three targets reserved.
e
committee completed its review by abandoning any pretension that its
objectives there were military:
e following conclusions were reached:
(1) not to specify aiming points, this is to be le to later determination
at base when weather conditions are known.
(2) to neglect location of industrial areas as pin point target, since on
these three targets such areas are small, spread on fringes of cities
and quite dispersed.
(3) to endeavor to place first gadget in center of selected city; that is,
not to allow for later 1 or 2 gadgets for complete destruction.
And that was that; the Target Committee would schedule no more meetings
but would remain on call.
Stimson abhorred bombing cities.
As he wrote in his third-person memoir
aer the war, “for thirty years Stimson had been a champion of international
law and morality.
As soldier and Cabinet officer he had repeatedly argued
that war itself must be restrained within the bounds of humanity....
Perhaps, as he later said, he was misled by the constant talk of ‘precision
bombing,’ but he had believed that even air power could be limited in its use
by the old concept of ‘legitimate military targets.’ ” Firebombing was “a kind
of total war he had always hated.
”2335 He seems to have conceived the idea
that even the atomic bomb could be somehow humanely applied, as he
discussed with Truman on May 16:
I am anxious to hold our Air Force, so far as possible, to the “precision” bombing which it has done
so well in Europe.
I am told that it is possible and adequate.
e reputation of the United States for
fair play and humanitarianism is the world’s biggest asset for peace in the coming decades.
I
believe the same rule of sparing the civilian population should be applied, as far as possible, to the
use of any new weapons.
2336
But the Secretary of War had less control over the military forces he was
delegated to administer than he would have liked, and nine days later, on
May 25, 464 of LeMay’s B-29’s—nearly twice as many as flew the first low-
level March 9 incendiary raid—once again successfully burned out nearly
sixteen square miles of Tokyo, although the Strategic Bombing Survey
asserts that only a few thousand Japanese were killed compared to the
86,000 it totals for the earlier conflagration.
e newspapers made much of
the late-May fire raid; Stimson was appalled.
On May 30 Groves crossed the river from his Virginia Avenue offices and
hove into view.2337 Stimson’s frustration at the bombing of Japanese cities
ignited a fateful exchange, as the general later told an interviewer:
I was over in Mr.
Stimson’s office talking to him about some matter in connection with the bomb
when he asked me if I had selected the targets yet.
I replied that I had that report all ready and I
expected to take it over to General Marshall the following morning for his approval.
Mr.
Stimson
then said: “Well, your report is all finished, isn’t it?” I said: “I haven’t gone over it yet, Mr.
Stimson.
I want to be sure that I’ve got it just right.” He said: “Well, I would like to see it” and I said: “Well,
it’s across the river and it would take a long time to get it.” He said: “I have all day and I know how
fast your office operates.
Here’s a phone on this desk.
You pick it up and you call your office and
have them bring that report over.” Well, it took about fieen or twenty minutes to get that report
there and all the time I was stewing and fretting internally over the fact that I was shortcutting
General Marshall....
But there was nothing I could do and when I protested slightly that I thought it was something that General Marshall should pass on first, Mr.
Stimson said: “is is one time
I’m going to be the final deciding authority.
Nobody’s going to tell me what to do on this.
On this
matter I am the kingpin and you might just as well get that report over here.” Well in the meantime
he asked me what cities I was planning to bomb, or what targets.
I informed him and told him that
Kyoto was the preferred target.
2338 It was the first one because it was of such size that we would have no question about the effects of the bomb....
He immediately said: “I don’t want Kyoto bombed.” And he went on to tell me about its long history as a cultural center of Japan, the former
ancient capital, and a great many reasons why he did not want to see it bombed.
When the report
came over and I handed it to him, his mind was made up.
ere’s no question about that.
He read
it over and he walked to the door separating his office from General Marshall’s, opened it and said:
“General Marshall, if you’re not busy I wish you’d come in.” And then the Secretary really double-
crossed me because without any explanation he said to General Marshall: “Marshall, Groves has
just brought me his report on the proposed targets.” He said: “I don’t like it.
I don’t like the use of
Kyoto.”
So Kyoto at least, the Rome of Japan, founded in 793, famous for silk and
cloisonné, a center of the Buddhist and Shinto religions with hundreds of
historic temples and shrines, would be spared, though Groves would
continue to test his superior’s resolve in the weeks to come.
e Imperial
Palace in Tokyo had been similarly spared even as Tokyo was laid waste
around it.
ere were still limits to the destructiveness of war: the weapons
were still modest enough to allow such fine discriminations.
e Interim Committee was to meet in full dress with its Scientific Panel
on ursday, May 31, and on Friday, June 1, with its industrial advisers.
e
Joint Chiefs of Staff prepared the ground for those meetings on May 25
when they issued a formal directive to the Pacific commanders and to Hap
Arnold defining U.S.
military policy toward Japan in the months to
come:2339
e Joint Chiefs of Staff direct the invasion of Kyushu (operation
OLYMPIC) target date 1 November 1945, in order to:
(1) Intensify the blockade and aerial bombardment of Japan.
(2) Contain and destroy major enemy forces.
(3) Support further advances for the purpose of establishing the
conditions favorable to the decisive invasion of the industrial heart
of Japan.
Truman had not yet signed on for the Japanese invasion.
One of his
advisers favored a naval blockade to starve the Japanese to surrender.
e
President would soon tell the Joint Chiefs that he would judge among his
options “with the purpose of economizing to the maximum extent possible
the loss of American lives.
”2340 Marshall, with MacArthur concurring from
the field, estimated that casualties—killed, wounded and missing—in the
first thirty days following an invasion of the southernmost Japanese home
island would not exceed 31,000.2341 An invasion of the main island of
Honshu across the plain of Tokyo would be proportionately more violent.
When Szilard returned to Washington from South Carolina he looked up
Oppenheimer, just arrived in town for the Interim Committee meeting, to
lobby him.
So hard was the Los Alamos director working to complete the
first atomic bombs that Groves had doubted two weeks earlier if he could
break free for the May 31 meeting.2342 Oppenheimer would not for the
world have missed the chance to advise at so high a level.
But his candid
vision of the future of the weapon he was building was as unromantic as his
understanding of its immediate necessity was, in Szilard’s view,
misinformed:
I told Oppenheimer that I thought it would be a very serious mistake to use the bomb against the
cities of Japan.
Oppenheimer didn’t share my view.
He surprised me by starting the conversation
by saying, “e atomic bomb is shit.” “What do you mean by that?” I asked him.
He said, “Well,
this is a weapon which has no military significance.2343 It will make a big bang—a very big bang—
but it is not a weapon which is useful in war.” He thought that it would be important, however, to
inform the Russians that we had an atomic bomb and that we intended to use it against the cities of
Japan, rather than taking them by surprise.
is seemed reasonable to me....
However, while this
was necessary it was certainly not sufficient.
“Well,” Oppenheimer said, “don’t you think that if we
tell the Russians what we intend to do and then use the bomb in Japan, the Russians will
understand it?” And I remember that I said, “ey’ll understand it only too well.”
Stimson’s insomnia troubled him on the night of May 30 and he arrived at
the Pentagon the next morning feeling miserable.
His committee assembled
at 10 A.M.
Marshall, Groves, Harvey Bundy and another aide attended by
invitation, but Stimson’s attention was focused on the four scientists, three of
them Nobel laureates.
e elderly Secretary of War welcomed them warmly,
congratulated them on their accomplishments and was concerned to
convince them that he and Marshall understood that the product of their
labor would be more than simply an enlarged specimen of ordnance.
e
handwritten notes he prepared emphasize the awe in which he held the
bomb; he was not normally a histrionic man:2344
S.l2345
Its size and character
We don’t think it mere new weapon
Revolutionary Discovery of Relation of man to universe
Great History Landmark like
Gravitation
Copernican eory
But,
Bids fair [to be] infinitely greater, in respect to its Effect
—on the ordinary affairs of man’s life.
May destroy or perfect International Civilization
May [be] Frankenstein or means for World Peace
Oppenheimer was surprised and impressed.
When Roosevelt died, he told
an audience late in life, he had felt “a terrible bereavement...
partly because
we were not sure that anyone in Washington would be thinking of what
needed to be done in the future.” Now he saw that “Colonel Stimson was
thinking hard and seriously about the implications for mankind of the thing
we had created and the wall into the future that we had breached.” 2346 And
though Oppenheimer knew Stimson had never sat down to talk with Niels
Bohr, the Secretary seemed to be speaking in terms derived at some near
remove from Bohr’s understanding of the complementarity of the bomb.
Aer Stimson’s introduction Arthur Compton offered a technical review
of the nuclear business, concluding that a competitor would need perhaps
six years to catch up with the United States.
Conant mentioned the
thermonuclear and asked Oppenheimer what gestation period that much
more violent mechanism would require; Oppenheimer estimated a
minimum of three years.
e Los Alamos director took the floor then to
review the explosive forces involved.
First-stage bombs, he said, meaning
crude bombs like Fat Man and Little Boy, might explode with blasts
equivalent to 2,000 to 20,000 tons of TNT.
at was an upward revision of
the estimate Bethe had supplied the Target Committee at Los Alamos in
mid-May.
Second-stage weapons, Oppenheimer went on—meaning
presumably advanced fission weapons with improved implosion systems—
might be equal to 50,000 to 100,000 tons of TNT.
ermonuclear weapons
might range from 10 million to 100 million tons TNT equivalent.
ese were numbers most of the men in the room had seen before and
were inured to.
Apparently Byrnes had not; they worried him gravely: “As I
heard these scientists...
predict the destructive power of the weapon, I was
thoroughly frightened.2347 I had sufficient imagination to visualize the
danger to our country when some other country possessed such a weapon.”
For now the President’s personal representative bided his time.
Entirely in energetic character, Ernest Lawrence spoke up for staying
ahead of the rest of the world by knowing more and doing more than any
other country.
He made explicit a future course for the nation about which
the previous record of all the meetings and deliberations is oddly silent, a
course based on assumptions diametrically opposite to Oppenheimer’s
profound insight that the atomic bomb was shit:
Dr.
Lawrence recommended that a program of plant expansion be vigorously pursued and at the
same time a sizable stock pile of bombs and material should be built up....
Only by vigorously
pursuing the necessary plant expansion and fundamental research...
could this nation stay out in
front.
at was a prescription for an arms race as soon as the Soviet Union took
up the challenge.
Arthur Compton immediately signed on.
So did his
brother Karl.
Oppenheimer contented himself with a footnote about
materials allocation.
Stimson eventually summarized the discussion:
1.
Keep our industrial plant intact.
2.
Build up sizeable stock piles of material for military use and for
industrial and technical use.
3.
Open the door to industrial development.
Oppenheimer demurred that the scientists should be released to return to
their universities and get back to basic science; during the war, he said, they
had been plucking the fruits of earlier research.
Bush emphatically agreed.
e committee turned to the question of international control and
Oppenheimer took the lead.
His exact words do not survive, only their
summary in the meeting notes kept by the young recording secretary,
Gordon Arneson, but if that summary is accurate, then Oppenheimer’s
emphasis was different from Bohr’s and misleading:
Dr.
Oppenheimer pointed out that the immediate concern had been to shorten the war.
e
research that had led to this development had only opened the door to future discoveries.
Fundamental knowledge of this subject was so widespread throughout the world that early steps
should be taken to make our developments known to the world.
He thought it might be wise for
the United States to offer to the world free interchange of information with particular emphasis on
the development of peace-time uses.
e basic goal of all endeavors in the field should be the
enlargement of human welfare.
If we were to offer to exchange information before the bomb was
actually used, our moral position would be greatly strengthened.
Where was Bohr’s understanding that the bomb was a source of terror but
for that very reason also a source of hope, a means of welding together
nations by their common dread of a menacing nuclear standoff?
e
problem was not exchanging information to improve America’s moral
standing; the problem was leaders sitting down and negotiating a way
beyond the mutual danger the new weapons would otherwise install.
e
opening up would emerge out of those negotiations, necessarily, to guarantee
safety; it could not in the real world of secrecy and suspicion realistically
precede them.
In 1963, lecturing on Bohr, Oppenheimer understood well
enough the fundamental weakness of his proposal:
Bush and Compton and Conant were clear that the only future they could envisage with hope was
one in which the whole development would be internationally controlled.
2348 Stimson understood this; he understood that it meant a very great change in human life; and he understood that the
central problem at that moment lay in our relations with Russia....
But there were differences:
Bohr was for action, for timely and responsible action.
He realized that it had to be taken by those
who had the power to commit and to act.
He wanted to change the whole framework in which this
problem would appear, early enough so that the problem would be altered by it.
He believed in
statesmen; he used the word over and over again; he was not very much for committees.
e
Interim Committee was a committee, and proved itself by appointing another committee, the
scientific panel.
No one should presume to judge these men as they struggled with a future
that even a mind as fundamental as Niels Bohr’s could only barely imagine.
But if Robert Oppenheimer ever had a chance to present Bohr’s case to those
who had the power to commit and to act he had it that morning.
He did not
speak the Dane’s hard plain truths.
He spoke instead as Aaron to Bohr’s
Moses.
And Bohr, though he waited nearby in Washington, had not been
invited to appear in the star chamber of that darkly paneled room.
Even Stimson thought Oppenheimer’s proposals misguided.
He asked
immediately “what would be the position of democratic governments as
against totalitarian regimes under such a program of international control
coupled with scientific freedom”—as if opening up the world would leave
either democratic or totalitarian nations unchanged, a confusion that
Oppenheimer’s confusion inspired.
Which led to further confusion: “e
Secretary said...
it was his own feeling that the democratic countries had
fared pretty well in this war.
Dr.
Bush endorsed this view vigorously.” Bush
then unwittingly outlined a domestic model of what Bohr’s larger open
world might be: “He said that our tremendous advantage stemmed in large
measure from our system of team work and free interchange of
information.” And promptly lapsed back into Stimson’s extended status quo:
“He expressed some doubt, however, of our ability to remain ahead
permanently if we were to turn over completely to the Russians the results of
our research under free competition with no reciprocal exchange.”
Odder and odder, and Byrnes sitting among them trying to imagine a
weapon equivalent to 100 million tons of TNT, trying to imagine what it
would mean to possess such a weapon and listening to these highly educated
men, men almost entirely of the Eastern establishment, of Harvard and MIT
and Princeton and Yale, blithely proposing, it seemed, to give away the
knowledge of how to make such a weapon.
Stimson le to attend a White House ceremony and they went on to speak
of Russia, which Byrnes knew as an advancing brutality currently devouring
Poland, and Oppenheimer again took the lead:
Dr.
Oppenheimer pointed out that Russia had always been very friendly to science and suggested
that we might open up this subject with them in a tentative fashion and in the most general terms
without giving them any details of our productive effort.
He thought we might say that a great
national effort had been put into this project and express hope for cooperation with them in this
field.
He felt strongly that we should not prejudge the Russian attitude in this matter.
Oppenheimer found an ally then in George Marshall, who “discussed at
some length the story of charges and counter-charges that have been typical
of our relations with the Russians, pointing out that most of these allegations
have proven unfounded.” Marshall thought Russia’s reputation for being
uncooperative “stemmed from the necessity of maintaining security.” He
believed a way to begin was to forge “a combination among like-minded
powers, thereby forcing Russia to fall in line by the very force of this
coalition.” Such bulldozing had worked in the gunpowder days now almost
past but it would not work in the days of the bomb; that power would be big
enough, as Oppenheimer’s estimates clarified, to make one nation alone a
match for the world.
e surprise of the morning was perhaps Marshall’s idea for an opening to
Moscow: “He raised the question whether it might be desirable to invite two
prominent Russian scientists to witness the [Trinity] test.” Groves must have
winced; aer the years of secrecy, aer the thousands of numb man-hours of
security work, that would be a renunciation worthy of Bohr himself.
Byrnes had heard enough.
He had sat behind Franklin Roosevelt at Yalta
making notes.
In all but the formalities he outranked even Henry Stimson.
He put his foot down and the seasoned committeemen moved smoothly
into line:
Mr.
Byrnes expressed a fear that if information were given to the Russians, even in general terms, Stalin would ask to be brought into the partnership.
He felt this to be particularly likely in
view of our commitments and pledges of cooperation with the British.
In this connection Dr.
Bush
pointed out that even the British did not have any of our blue prints on plants.
Mr.
Byrnes expressed the view, which was generally agreed to by all present, that the most desirable program
would be to push ahead as fast as possible in production and research to make certain that we stay
ahead and at the same time make every effort to better our political relations with Russia.
When Stimson returned, Compton summed up the sense of the crucial
discussion the Secretary of War had missed—“the need for maintaining
ourselves in a position of superiority while at the same time working toward
adequate political agreements.” Marshall le them for duty and the rest of
the committee trooped off to lunch.
ey sat at adjoining tables in a Pentagon dining room.
ey were a
civilian committee; separate conversations converged on the same question,
only briefly mentioned during the morning and not taken up: was there no
way to let this cup pass from them?
Must Little Boy be dropped on the
Japanese in surprise?
Could their stubborn enemy not be warned in advance
or a demonstration arranged?2349
Stimson, at the focus of one conversation (Byrnes the center of the other),
may have spoken then of his outrage at the mass murder of civilians and his
complicity; Oppenheimer remembered such a statement at some time
during the day and lunch was the only unstructured occasion:
[Stimson emphasized] the appalling lack of conscience and compassion that the war had brought
about...
the complacency, the indifference, and the silence with which we greeted the mass
bombings in Europe and, above all, Japan.
He was not exultant about the bombings of Hamburg, of
Dresden, of Tokyo....
Colonel Stimson felt that, as far as degradation went, we had had it; that it
would take a new life and a new breath to heal the harm.
e only recorded response to Stimson’s mea culpa is Oppenheimer’s
admiration for it, but there were a number of responses to the question of
warning the Japanese or demonstrating the atomic bomb.
Oppenheimer
could not think of a suitably convincing demonstration:2350
You ask yourself would the Japanese government as then constituted and with divisions between
the peace party and the war party, would it have been influenced by an enormous nuclear
firecracker detonated at a great height doing little damage and your answer is as good as mine.
I
don’t know.
2351
Since the Secretary of State-designate had power to commit and to act, the
significant responses to the question are Byrnes’.
In a 1947 memoir he
recalled several:
We feared that, if the Japanese were told that the bomb would be used on a given locality, they
might bring our boys who were prisoners of war to that area.
Also, the experts had warned us that
the static test which was to take place in New Mexico, even if successful, would not be conclusive
proof that a bomb would explode when dropped from an airplane.
If we were to warn the Japanese
of the new highly destructive weapon in the hope of impressing them and if the bomb then failed
to explode, certainly we would have given aid and comfort to the Japanese militarists.
2352
ereaer, the Japanese people probably would not be impressed by any statement we might make
in the hope of inducing them to surrender.
In a later television interview he emphasized a more political concern: “e
President would have had to take the responsibility of telling the world that
we had this atomic bomb and how terrific it was...
and if it didn’t prove out
what would have happened to the way the war went God only knows.” 2353
Someone among the assembled, Ernest Lawrence remembers, concluded
that the “number of people that would be killed by the bomb would not be
greater in general magnitude than the number already killed in fire raids,”
making those slaughters a baseline, as indeed before the awful potential of
the new weapon they were.2354
ese troubled men returned to Stimson’s office and spent most of the
aernoon considering the effect of the bombing on the Japanese and their
will to fight.
Someone unnamed chose to discredit the atomic bomb’s
destructiveness, asserting it “would not be much different from the effect
caused by any Air Corps strike of present dimensions.” Oppenheimer
defended his creation’s pyrotechnics, citing the electromagnetic and nuclear
radiation it would expel:
Dr.
Oppenheimer stated that the visual effect of an atomic bombing would be tremendous.
It would
be accompanied by a brilliant luminescence which would rise to a height of 10,000 to 20,000 feet.
e neutron effect of the explosion would be dangerous to life for a radius of at least two-thirds of
a mile.2355
It was probably during this aernoon discussion that Oppenheimer
reported an estimate prepared at Los Alamos of how many deaths an atomic
bomb exploded over a city might cause.
Arthur Compton remembers the
number as 20,000, an estimate based on the assumption, he says, that the
city’s occupants would seek shelter when the air raid began and before the
bomb went off.
He recalls Stimson bringing up Kyoto then, “a city that must
not be bombed.” e Secretary still insisted passionately that “the objective
was military damage...
not civilian lives.” 2356
e contradiction in Stimson’s caveat persisted into his summary of the
aernoon’s findings, which he offered before he le the meeting at three
thirty:
Aer much discussion concerning various types of targets and the effects to be produced, the
Secretary expressed the conclusion, on which there was general agreement, that we could not give the Japanese any warning; that we could not concentrate on a civilian area; but that we should seek to
make a profound psychological impression on as many of the inhabitants as possible.
At the suggestion
of Dr.
Conant the Secretary agreed that the most desirable target would be a vital war plant employing a large number of workers and closely surrounded by workers’ houses.
Which had been the general formula in Europe, but according to Curtis
LeMay the Japanese worked at home, as families:
We were going aer military targets.
No point in slaughtering civilians for the mere sake of
slaughter.
Of course there is a pretty thin veneer in Japan, but the veneer was there.
It was their
system of dispersal of industry.
All you had to do was visit one of those targets aer we’d roasted it,
and see the ruins of a multitude of tiny houses, with a drill press sticking up through the wreckage
of every home.
e entire population got into the act and worked to make those airplanes or
munitions of war...
men, women, children.
We knew we were going to kill a lot of women and
kids when we burned [a] town.
Had to be done.
2357
Stimson had now le the meeting.
Arthur Compton wanted to talk about
problems at the Met Lab.
Before that final discussion the spirit of Leo Szilard
bustled through the room.
Groves had just learned of another round of
Szilardian conspiracy.
e general was wrathful: “General Groves stated that
the program has been plagued since its inception by the presence of certain
scientists of doubtful discretion and uncertain loyalty.” Szilard had traveled
on to New York aer talking to Oppenheimer and that very morning had
looked up Boris Pregel, the Russian-born French metals speculator and bon
vivant who had helped out in the early Columbia days and whose mine on
Great Bear Lake supplied the Manhattan Project with uranium ore.
On May
16 Szilard had sent Pregel a version of his Truman memorandum.
(Groves
knew all this from what he calls “secret intelligence sources.”) Meeting with
Pregel fresh from the May 28 meeting with Byrnes, Szilard had “expressed
the opinion,” says Groves, “that someone high in the Government [i.e.,
Byrnes] had been completely misinformed as to [Russian] sources of ore by
the [U.S.] Army.
He claimed that the misinformation was given
intentionally.
”2358 Two could play at sniffing conspiracy, and even in the
midst of debate on the necessity of total death in total war, they did.
e next morning, June 1, the Interim Committee met with four
industrialists.
2359 Walter S.
Carpenter, the president of Du Pont, estimated
that the Soviet Union would need “at least four or five years” to construct a
plutonium production facility like Hanford.
James White, president of
Tennessee Eastman, “doubted whether Russia would be able to secure
sufficient precision in its equipment to make [an electromagnetic separation
plant] possible” at all.
George Bucher, the president of Westinghouse,
thought that if the Soviets acquired the services of German technicians and
scientists they might build an electromagnetic operation in three years.
A
vice president of Union Carbide, James Rafferty, offered the longest odds:
ten years to build a gaseous-diffusion plant from the ground up—but only
three years if the Soviets ferreted out barrier technology by espionage.
Mentally Byrnes added processing time to plant construction: “I
concluded that any other government would need from seven to ten years, at
least, to produce a bomb.” 2360 From a political point of view seven years was
a millennium.
Stimson still quailed at destroying entire cities with atomic bombs.
In the
aernoon, absenting himself from the Interim Committee discussions, he
distanced that horror by pursuing the precision-bombing question further
with Hap Arnold, whom he says he “sternly questioned.” 2361 “I told him of
my promise from [War Department Undersecretary for Air Robert] Lovett
that there would be only precision bombing in Japan....
2362 I wanted to
know what the facts were.” Arnold told Stimson the one about dispersed
Japanese industry.
Area bombing was the only way to get at all those drill
presses.
“He told me, however, that they were trying to keep it down as far as
possible.” Stimson was willing a few days later to pass that tale along to
Truman, with a brace of ambivalent motives thrown in for good measure:
I told him how I was trying to hold the Air Force down to precision bombing but that with the
Japanese method of scattering its manufacture it was rather difficult to prevent area bombing.
I
told him I was anxious about this feature of the war for two reasons: First, because I did not want
to have the United States get the reputation for outdoing Hitler in atrocities; and second, I was a
little fearful that before we could get ready, the Air Force might have Japan so thoroughly bombed
out that the new weapon would not have a fair background to show its strength.
He said he
understood.
While Stimson was away Byrnes swily and decisively co-opted the
committee.
“Mr.
Byrnes felt that it was important there be a final decision on
the question of the use of the weapon,” recording secretary Arneson recalled
aer the war.2363 He described the decision-making process in the minutes
he took on June 1:
Mr.
Byrnes recommended, and the Committee agreed, that the Secretary of War should be advised that, while recognizing that the final selection of the target was essentially a military decision, the
present view of the Committee was that the bomb should be used against Japan as soon as possible;
that it be used on a war plant surrounded by workers’ homes; and that it be used without prior
warning.2364
It remained to carry the decision to the President for endorsement.
Byrnes
headed straight for the White House as soon as the Interim Committee
adjourned:
I told the President of the final decision of his Interim Committee.
Mr.
Truman told me he had
been giving serious thought to the subject for many days, having been informed as to the
investigation of the committee and the consideration of alternative plans, and that with reluctance
he had to agree that he could think of no alternative and found himself in accord with what I told
him the Committee was going to recommend.2365
Truman saw his Secretary of War five days later.
e President, Stimson
noted in his diary, “said that Byrnes had reported to him already about [the
Interim Committee’s decision] and that Byrnes seemed to be highly pleased
with what had been done.
”2366
Harry Truman did not give the order to drop the atomic bomb on June 1.
But he appears to have made the decision then, with a little help from Jimmy
Byrnes.
Aer the Interim Committee meeting on May 31 Robert Oppenheimer
had sought out Niels Bohr.
“I was very deeply impressed with General
Marshall’s wisdom,” he remembered in 1963, “and also that of Secretary
Stimson; and I went over to the British mission and met Bohr and tried to
comfort him; but he was too wise and too worldly to be comforted, and he
le for England very soon aer that, quite uncertain about what, if anything,
would happen.
”2367
Before Bohr le, late in June, he attempted one last time to see a high
official of the United States government—Stimson—Harvey Bundy sending
in a message on June 18 to the Secretary: “Do you want to try and work in a
meeting with Professor Bohr, the Dane, before you get away this week?
”2368
At the side of the memorandum, in bold script, whether from exhaustion
or impatience or because he understood that the matter had been taken out
of his hands, Henry Stimson struck finally: “No.”
* * *
No one doubted that Little Boy would work if any design would.
Otto
Frisch’s Dragon experiments had proven the efficacy of the fast-neutron
chain reaction in uranium.
e gun mechanism was wasteful and inefficient
but U235 was forgiving.
It remained to test implosion.
While doing so the
physicists could also compare their theory of the progress of such an exotic
release of energy with the huge blinding fact.
Trinity would be the largest
physics experiment ever attempted up to that time.2369
e hard work of finding a proving ground sufficiently barren and remote
and organizing it fell to a compact, close-cropped Harvard experimental
physicist named Kenneth T.
Bainbridge.
His task, the Los Alamos technical
history notes, “was one of establishing under conditions of extreme secrecy
and great pressure a complex scientific laboratory in a barren desert.” 2370
Bainbridge was well qualified.
From Cooperstown, New York, the son of a
wholesale stationer, he had worked under Ernest Rutherford at the
Cavendish and had designed and built the Harvard cyclotron that now
served the Manhattan Project’s purposes on the Hill.
He had brought back
word of the MAUD Committee report to Vannevar Bush in the summer of
1941 and had worked at MIT and in Great Britain on radar.
Robert Bacher
had recruited him for Los Alamos in the summer of 1943.
Beginning in
March 1944 he took charge of Trinity.
He needed a flat, desolate site with good weather, near enough to Los
Alamos to make travel convenient but far enough away to obscure obvious
connection.
From map data he chose eight sites, including a desert training
area in southern California, the Texas Gulf sandbar region now known as
Padre Island and several barren dry valleys in southern New Mexico.
Riding
three-quarter-ton weapons carriers with Robert Oppenheimer and a team of
Army officers in May 1944, Bainbridge led an exploration of the New
Mexico sites through late snow; carrying along food and water and sleeping
bags, he remembers, they “followed unmapped ranch trails past deserted
areas of dry farming lands beaten by too many years of drought and high
winds.
”2371 For Oppenheimer it was a rare escape from the daily burdens of
directing Los Alamos, one he was not able to repeat.
Several explorations
later Bainbridge chose a flat scrub region some sixty miles northwest of
Alamogordo between the Rio Grande and the Sierra Oscura, known
ominously from Spanish times as the Jornada del Muerto—the dry and
therefore dangerous Dead Man’s Trail, the Journey of Death.
Two hundred
ten miles south of Los Alamos, the Jornada formed the northwest sector of
the Alamogordo Bombing Range; with the permission of Second Air Force
Commander Uzal Ent, Bainbridge staked out an eighteen-by-twenty-four-
mile claim.
e demands of the implosion crisis in the autumn of 1944 reduced
Trinity’s priority, says Bainbridge, “almost to zero...
until the end of
February 1945.” 2372 With bomb physics well in hand by then Oppenheimer
set the test shot’s target date at July 4 and Bainbridge got busy.
His staff of
twenty-five increased across the next five months to more than 250.
Herbert
Anderson, P.
B.
Moon, Emilio Segrè and Robert Wilson carried major
responsibilities; William G.
Penney, Enrico Fermi and especially Victor
Weisskopf served as consultants.
e Army leased the David McDonald ranch in the middle of the Jornada
site and renovated it for a field laboratory and Military Police station.
About
3,400 yards northwest of McDonald Ranch Bainbridge marked out Ground
Zero.
From that center, at compass points roughly north, west and south at
10,000-yard distances, Corps of Engineers contractors built earth-sheltered
bunkers with concrete slab roofs supported by oak beams thicker than
railroad ties.
N-10000, 5.7 miles from Zero, would house recording
instruments and searchlights; W-10000 would house searchlights and banks
of high-speed cameras; S-10000 would serve as the control bunker for the
test.
Another five miles south beyond S-10000 a Base Camp of tents and
barracks took shape.
A hill named Compañia twenty miles northwest of Zero on the edge of the
Jornada would serve as a VIP scenic overlook.
e Oscuras to the east rose
more than 4,000 feet above the high alkaline plain.
e Jornada was host to gray hard mesquite, to yucca sharp as the swords
of samurai, to scorpions and centipedes men shook in the morning from
their boots, to rattlesnakes and fire ants and tarantulas.
e MP’s hunted
antelope with machine guns for fresh meat and for sport.
Groves authorized
only cold showers for his troops; their isolated duty would win them
eventual award for the lowest VD rate in the entire U.S.
Army.
e well
water, fouled with gypsum, made a sovereign purgative.
It also stiffened the
hair.
Contractors built two towers.
One, 800 yards south of Zero, they bolted
together 20 feet high in trestles of heavy beams like those that framed the
bunkers.
It supported a wide platform like an outdoor dance floor and one
day in early May the builders returned from a mandated layoff to find it had
vanished.
Bainbridge had seen it stacked with 100 tons of high explosives in
wooden boxes, had packed canisters of dissolved hot Hanford slugs at the
center and before dawn on May 7 had blown the entire stack, the largest
chemical explosion ever deliberately set off, merely to practice routines and
try out instruments.
e dirt roads had caused delays; he demanded twenty-
five miles of paved roads from Groves as a result and got them, and
tightened up procedures for the one and only nuclear test to come.
e tower went up at Zero.
It had been prefabricated of steel and shipped
to the site in sections.
Concrete footings poured through the hard desert
caliche 20 feet into the earth supported its four legs, which were spaced 35
feet apart; braced with crossed struts it rose 100 feet into the air, culminating
in an oak platform roofed and sheltered on three sides with sheets of
corrugated iron.
e iron shack’s open side faced toward the camera bunker
to the west.
A removable section at the center of the platform gave access to
the ground below.
e high-iron workers who finished the tower installed
bracing at the top for a $20,000 electrically driven heavyduty winch.
Frank Oppenheimer, a Berkeley physics Ph.D.
working for his brother
now troubleshooting the test, remembers that when he arrived at Trinity in
late May “people were feverishly setting up wires all over the desert, building
the tower, building little huts in which to put cameras and house people at
the time of the explosion.” 2373 e reinforced concrete camera bunkers had
portholes of thick bulletproof glass.
Hundreds of 6-foot wooden T-poles
strung thick as a loom frame with 500 miles of wire walked away from Zero
to the instrument bunkers safe miles beyond; other wires buried
underground ran protected inside miles of premium garden hose.
Besides photographic studies three kinds of experiments concerned
Bainbridge and his team.
One set, by far the most extensive, would measure
blast, optical and nuclear effects with seismographs, geophones, ionization
chambers, spectrographs, films and a variety of gauges.
A second would
study the implosion in detail and check the operation of the new exploding-
wire detonators Luis Alvarez had invented.
Experiments planned by Herbert
Anderson to reveal the explosive yield radiochemically made up the third
category.
Harvard physicist David Anderson (no relation) arranged to
acquire two Army tanks for that work and to pressurize them and line them
with lead; Herbert Anderson and Fermi meant to ride them close to the
crater at Zero immediately aer the shot, scoop up some of the radioactive
debris with a tethered cup hitched to a rocket fired into the crater and
retrieve the material for laboratory measurement.
Its ratio of fission
products to unfissioned plutonium would reveal the yield.
By May 31 enough plutonium had arrived at Los Alamos from Hanford to
begin critical-mass experiments.
Seth Neddermeyer’s shell-configured core
had been abandoned even though thin-walled shells give the highest
compressions in implosion.
Designing out their hydrodynamic instabilities
required calculations too dificult to accomplish by hand.
Berkeley
theoretician Robert Christy designed a more conservative solid core, two
mated hemispheres totaling less than one critical mass that implosion would
squeeze to at least double their previous density, shortening the distance that
fission neutrons would have to travel between nuclei and rendering the mass
supercritical.
Frisch’s group confirmed the core configuration
experimentally on June 24.
For the high-density form of Pu the critical mass
within a heavy tamper is eleven pounds; even with a nutsized central hollow
to encapsulate an initiator the Trinity core cannot have been larger than a
small orange.
2374
Delivery of full-sized molds for the implosion lens segments paced the
test; they began arriving in quantity only in June, and on June 30 the
committee responsible for deciding the test date moved it back to July 16 at
the earliest.
Kistiakowsky’s group worked night and day at S-Site to make
enough lenses.
“Most troublesome were the air cavities in the interior of the
large castings,” he recalled aer the war, “which we detected by x-ray
inspection techniques but could not repair.
More rejects than acceptable
castings were usually our unfortunate lot.” 2375, 2376
Groves met with Oppenheimer and Parsons on June 27 to lay plans for
shipping the first atomic bombs to the Pacific.
ey agreed to send the Little
Boy U235 projectile by water and the several U235 target pieces later by air;
the shipping program acquired the code name Bronx because of that New
York borough’s adjacency to Manhattan.
e metallurgists at Los Alamos
cast one target piece before the end of June and the U235 bullet on July 3.
e next day, Independence Day, the Combined Policy Committee met in
Washington and the British officially gave their approval, as the Quebec
Agreement provided, for the use of atomic bombs on Japan.
Truman had agreed to meet with Stalin and Churchill in the Berlin suburb
of Potsdam sometime during the summer; he told Stimson on June 6 that he
had succeeded in postponing the conference until July 15 “on purpose,”
Stimson wrote in his diary, “to give us more time.
”2377 ough Truman and
Byrnes had not yet decided to tell Stalin about the atomic bomb, a successful
test would change the Pacific equation; they might not need a Soviet
invasion of Manchuria to challenge the Japanese and might therefore have to
trade away less in Europe.
To make sure the President had news of the test at
Potsdam, Groves decided during the first week in July to fix the test date at
July 16, subject to the vagaries of the weather.
He had learned late in June of
the possibility of dangerous radioactive fallout over populated areas of New
Mexico—“What are you,” he berated the Los Alamos physician who gave
him the news, “some kind of Hearst propagandist?”—or he would not have
waited even on the weather.2378
So the shot was set for sometime in mid-July, in the heat of the desert
summer when the temperature on the Jornada oen burned above 100° late
in the day.
Oppenheimer wired Arthur Compton and Ernest Lawrence: ANY
TIME AFTER THE 15TH WOULD BE A GOOD TIME FOR OUR FISHING TRIP.
BECAUSE WE
ARE NOT CERTAIN OF THE WEATHER WE MAY BE DELAYED SEVERAL DAYS.
2379
e senior men arranged a betting pool with a one-dollar entry fee,
wagering on the explosive yield.
Edward Teller optimistically picked 45,000
tons TNT equivalent.
Hans Bethe picked 8,000 tons, Kistiakowsky 1,400.
Oppenheimer chose a modest 300 tons.
Norman Ramsey took a cynical
zero.
When I.
I.
Rabi arrived a few days before the test the only bet le was
for 18,000 tons; whether or not he believed that might be the Trinity yield,
he bought it.
As of July 9 Kistiakowsky did not yet have enough quality lens castings on
hand to assemble a complete charge.2380 Oppenheimer further compounded
his troubles by insisting on firing a Chinese copy of the gadget a few days
before the Trinity shot to test its high-explosive design at full scale with a
nonfissionable core.
Each unit would require ninety-six blocks of explosive.
Kistiakowsky resorted to heroic measures:
In some desperation, I got hold of a dental drill and, not wishing to ask others to do an untried job, spent most of one night, the week before the Trinity test, drilling holes in some faulty castings so as
to reach the air cavities indicated on our x-ray inspection films.
at done, I filled the cavities by
pouring molten explosive slurry into them, and thus made the castings acceptable.
Overnight,
enough castings were added to our stores by my labors to make more than two spheres.2381
“You don’t worry about it,” he adds fatalistically.2382 “I mean, if fiy pounds
of explosives goes in your lap, you won’t know it.”
Navy Lieutenant Commander Norris E.
Bradbury, a brisk, energetic
Berkeley physics Ph.D., took charge of assembling the high explosives.
On
Wednesday, July 11, he met with Kistiakowsky to sort the charges according
to their quality.
“e castings were personally inspected by Kistiakowsky
and Bradbury for chipped corners, cracks, and other imperfections,” writes
Bainbridge.
“...
Only first-quality castings which were not chipped or
which could be easily repaired were used for the Trinity assembly.
e
remainder of the castings were diverted for the Creutz charge”—so named
for Edward Creutz, the physicist who was running the Chinese copy test.
2383
e castings were waxy, mottled, brown with varnish.
ey weighed in total,
for each device, about 5,000 pounds.
Everyone felt the pressure of the approaching test.
It took its toll.
“at
last week in many ways dragged,” Elsie McMillan remembers; “in many ways
it flew on wings.
2384 It was hard to behave normally.
It was hard not to think.
It was hard not to let off steam.
We also found it hard not to overindulge in
all the natural activities of life.” In a letter to Eleanor Roosevelt in 1950
Oppenheimer recalled an odd group delusion:
Very shortly before the test of the first atomic bomb, people at Los Alamos were naturally in a state
of some tension.
I remember one morning when almost the whole project was out of doors staring
at a bright object in the sky through glasses, binoculars and whatever else they could find; and nearby Kirtland Field reported to us that they had no interceptors which had enabled them to
come within range of the object.
Our director of personnel was an astronomer and a man of some
human wisdom; and he finally came to my office and asked whether we would stop trying to shoot
down Venus.
I tell this story only to indicate that even a group of scientists is not proof against the
errors of suggestion and hysteria.2385
By then the two small plutonium hemispheres had been cast, and plated
against corrosion and to absorb alpha particles with nickel, which made the
assembly, as metallurgist Cyril Smith would write, “beautiful to gaze
upon.
”2386 But “an unscheduled change began to be evident three or four
days before the scheduled date.” Plating solution trapped beneath the plating
on the flat faces of the hemispheres began to blister the nickel, spoiling the
fit.
“For a time,” says Smith, “postponement of the whole event was
threatened.” 2387 Completely filing off the blisters would expose the
plutonium.
e metallurgists salvaged the castings by grinding only partway
through the blisters and smoothing the bumpy fit with sheets of gold foil.
e core of the first atomic bomb would go to its glory dressed in
improvised offerings of nickel and gold.
A tropical air mass moved north over Trinity on July 10, just as the test
meteorologist, Caltech-trained Jack M.
Hubbard, thirty-nine years old, had
predicted.
Hubbard had resisted the July 16 date, a Monday, since he first
heard of it; he expected bad weather that weekend.
e Gulf air suspended
salt crystals that diffused a slight haze.
On July 12, worrying about Potsdam,
Groves confirmed the test for the morning of July 16.
Bainbridge passed the
word to Hubbard.
“Right in the middle of a period of thunderstorms,” the
meteorologist stormed to his journal, “what son-of-a-bitch could have done
this?” Groves had been awarded such scurrilous genealogy before.
2388
e general’s decision started Norris Bradbury and his crews of Special
Engineering Detachment GI’s—SED’s, the science-trained recruits were
called—assembling the Trinity and Creutz high-explosive charges at two
separate canyon sites near Los Alamos mesa that ursday.
ey debated
filling the small air spaces between the castings with grease.
Kistiakowsky
decided against such filler, writes Bainbridge, “on the basis that the castings
assembled were much better than any previously made and that the air
spaces le by the spacer materials were insignificant.” 2389 e charges, each
of which had been X-rayed one last time and numbered, were papered into
snugness instead with facial tissue and Scotch tape.
e simplified and
improved casing of the unit to be tested, which was designated model 1561,
differed from the earlier 1222 casing of bolted pentagons; it featured an
equatorial band of five segments machined from dural castings to which
were bolted large upper and lower domed polar caps.
When the explosives
that lined the lower hemisphere had been papered into place Bradbury’s
SED’s winched down the heavy tamper sphere of natural uranium, which
filled the cavity like the pit in an avocado.
e tamper was missing a
cylindrical plug; the resulting hole would receive the core assembly.
e
explosive blocks that formed the upper shell followed next.
For transport to Trinity one set of castings was temporarily le out,
replaced by a trapdoor plug through which the core assembly could be
positioned in the tamper.
e reserved castings—an inner of solid
Composition B, an outer lensed—were boxed separately with one spare of
each type.
e men completed preparing the HE assembly for the slow drive
down to Trinity by bagging it in waterproof Butvar plastic, boxing it in a
braced shipping crate of knotty pine and lashing the resulting package
securely to the bed of a five-ton Army truck.
A tarpaulin then muffled its
secrets in inconclusive drape.
e plutonium core le the Hill first, at three that ursday aernoon,
shock-mounted in a field carrying case studded with rubber bumpers with a
strong wire bail.
It rode with Philip Morrison in the backseat of an Army
sedan like a distinguished visitor, a carload of armed guards clearing the way
ahead and another of pit-assembly specialists bringing up the rear.
Morrison
also delivered a real and a simulated initiator.
At about six o’clock a
sunburned young sergeant in a white T-shirt and summer uniform pants
carried the plutonium core in its field case into the room at McDonald
Ranch where it would spend the night.
Guards surrounded the ranchhouse
to keep vigil.
For security and to encounter less road traffic the HE assembly would
make the trip by night; Kistiakowsky deliberately scheduled that more
conspicuous convoy to leave at one minute aer midnight on Friday, July 13,
to put reverse English on the day’s unlucky reputation.
He rode in the lead
car with the security guards.
He soon dozed off and was then startled awake
by the scream of the car’s siren as the convoy ran through Santa Fe; the
Army wanted no late-night drunken drivers rolling out of sidestreets to
collide with its truckload of handmade high explosives.
Beyond Santa Fe the
convoy slowed again to below thirty miles an hour; the haul to Trinity took
eight hours and Kistiakowsky got some sleep.
On Friday morning at nine the pit-assembly team gathered in white lab
coats at McDonald Ranch to begin the final phase of its work.
Brigadier
General omas Farrell was on hand as Groves’ deputy, Robert Bacher as
the team’s senior adviser.
Bainbridge looked in; so did Oppenheimer.
e
ranchhouse room where the core had spent the night had been thoroughly
vacuumed in preparation and its windows sealed against dust with black
electrical tape to convert it to a makeshi clean room.
On a table there the
assemblers spread crisp brown wrapping paper and laid out the pieces of
their puzzle: two gold-faced, nickel-plated hemispheres of plutonium, a
shiny beryllium initiator hot with polonium alphas and, to confine these
crucial elements, the several pieces of plum-colored natural uranium that
formed the cylindrical 80-pound plug of tamper.
Before assembly began
Bacher asked for a receipt from the Army for the material it would soon
explode.
Los Alamos was officially an extension of the University of
California working for the Army under contract and Bacher wanted to
document the university’s release from responsibility for some millions of
dollars’ worth of plutonium that would soon be vaporized.
Bainbridge
thought the ceremony a waste of time but Farrell saw its point and agreed.
To relieve the tension Farrell insisted on heing the hemispheres first to
confirm that he was getting good weight.
Like polonium but much less
intensely, plutonium is an alpha emitter; “when you hold a lump of it in your
hand,” says Leona Marshall, “it feels warm, like a live rabbit.
”2390 at gave
Farrell pause; he set the hemispheres down and signed the receipt.
e parts were few but the men worked carefully.
ey nested the initiator
between the two plutonium hemispheres; they nested the nickel ball in turn
in its hollowed plug of tamper.
at required the morning and half the
aernoon.
Two men lugged the heavy boxed assembly on a barrow out to
the car.
It arrived in its lethal dignity at Zero at 3:18 P.M.
ere Norris Bradbury’s crew had been busy with the five-foot sphere of
high explosives Kistiakowsky had delivered that morning.
At 1 P.M.
the truck
driver had backed his load under the tower.
e men had used a jib winch to
li off the wooden packing crate, had swung it aside and lowered around the
sphere a massive set of steel tongs suspended from the main winch anchored
one hundred feet up at the top of the tower.
With the tongs securing the
sphere its two tons were winched up off the truck bed; the driver pulled the
truck away and the winch lowered the preassembled unit to a skid set on the
asphalt-paved ground.
“We were scared to death that we would drop it,”
Bradbury recalls, “because we didn’t trust the hoist and it was the only bomb
immediately available.
It wasn’t that we were afraid of setting it off, but we
might damage it in some way.
”2391 Before they opened the upper polar cap to
expose the trapdoor plug they erected a white tent over the assembly area;
thereaer a diffused glow of sunlight illuminated their work.
Inserting the plug courted disaster, team member Boyce McDaniel
remembers:
e [high-explosive] shell was incomplete, one of the lenses was missing.2392 It was through this opening that the cylindrical plug containing the plutonium and initiator was to be inserted....
In
order to maximize the density of the uranium in the total assembly, the clearance between the plug
and the spherical shell had been reduced to a few thousandths of an inch.
Back at Los Alamos,
three sets of these plugs and [tamper spheres] had been made.
However, in the haste of last minute
production, the various units had not been made interchangeable, so not all of the plugs would fit
into all [holes].
Great care had been exercised to make sure, however, that mating pieces had been
shipped to [Trinity].
Imagine our consternation when, as we started to assemble the plug in the hole, deep down in
the center of the high explosive shell, it would not enter!
Dismayed, we halted our efforts in order
not to damage the pieces, and stopped to think about it.
Could we have made a mistake...
?
Bacher saw the cause and calmed them: the plug had warmed and expanded
in the hot ranchhouse but the tamper, set deep within the insulation of its
shell of high explosives, was still cool from Los Alamos.
e men le the two
pieces of heavy metal in contact and took a break.
When they checked the
assembly again the temperatures had equalized.
e plug slid smoothly into
place.
en it was the turn of the explosives crew.
Oppenheimer watched over
them, conspicuous in his pork-pie hat, wasted to 116 pounds by a recent
bout of chicken pox and the stress of months of late nights and sevenday
weeks.
In the motion picture that documents this historic assembly he darts
in and out of the frame like a foraging water bird, pecking at the open well of
the bomb.
Someone hands Bradbury a strip of Scotch tape and his arms
disappear into the well to secure a block of explosive.
He finished the work
in late evening under lights.
e detonators were not yet installed.
at
would be the next day’s challenge aer the unit had been hauled to the top of
the tower.
e following morning, Saturday, around eight, Bradbury supervised
raising the test device to its high platform.
e openings into the casing
where the detonators would be inserted had been covered and taped to keep
out dust; as the bulky sphere rose into the air it revealed itself generously
bandaged as if against multiple wounds.
It stopped at fieen feet long
enough to allow a crew of GI’s to stack depths of striped tickingcovered
Army mattresses up nearly to its skid, a prayer in cotton batting against a
damaging fall.
en it started up again, twisting slowly, seeming on its thin,
braided steel cable to levitate, rising the full height of the tower and
diminishing slightly with distance as it rose.
Two sergeants received it into
the tower shack through the open floor, replaced the floor panel and lowered
the unit onto its skid, positioning it with its north and south polar caps at
le and right rather than above and below as they had been positioned
during assembly, the same posture in which its militant armored twin, Fat
Man, would ride to war in the bomb bay of a B-29.
e delicate work of
inserting the detonators then began.
Disaster loomed again that day.
e Creutz group at Los Alamos had fired
the Chinese copy, measured the simultaneity of its implosion by the
magnetic method and called Oppenheimer to report the dismaying news
that the Trinity bomb was likely to fail.
“So of course,” says Kistiakowsky, “I
immediately became the chief villain and everybody lectured me.” 2393, 2394
Groves flew in to Albuquerque in his official plane with Bush and Conant at
noon; they were appalled at the news and added their complaints to
Kistiakowsky’s full burden:
Everybody at headquarters became terribly upset and focused on my presumed guilt.
Oppenheimer, General Groves, Vannevar Bush—all had much to say about that incompetent
wretch who forever aer would be known to the world as the cause of the tragic failure of the Manhattan Project.
Jim Conant, a close personal friend, had me on the carpet it seemed for hours,
coldly quizzing me about the causes of the impending failure.
Sometime later that day Bacher and I were walking in the desert and as I timidly questioned the
results of the magnetic test Bob accused me of challenging no less than Maxwell’s equations
themselves!
At another point Oppenheimer became so emotional that I offered him a month’s
salary against ten dollars that our implosion charge would work.
In the midst of this contretemps all of Little Boy but its U235 target pieces
slipped away.
With two Army officers in escort, a closed black truck and
seven carloads of security guards le Los Alamos Saturday morning for
Kirtland Air Force Base in Albuquerque.
A manifest describes the truck’s
expensive cargo:
a.
1 box, wt.
about 300 lbs, containing projectile assembly of active
material for the gun type bomb.
2395
b.
1 box, wt.
about 300 lbs, containing special tools and scientific
instruments.
c.
1 box, wt.
about 10,000 lbs, containing the inert parts for a complete
gun type bomb.
Two DC-3’s waiting at Kirtland flew the crates and their officer escorts to
Hamilton Field, near San Francisco, from which another security convoy
escorted them to Hunter’s Point Naval Shipyard to await the sailing of the
U.S.S.
Indianapolis, the heavy cruiser that would deliver them to Tinian.
At Trinity gloom was everywhere.
A physical chemist from Los Alamos,
Joseph O.
Hirschfelder, remembers Oppenheimer’s discomfiture that
Saturday evening at the hotel where the guests invited to view the test had
begun to assemble: “We drove to the Hilton Hotel in Albuquerque, where
Robert Oppenheimer was meeting with a large group of generals, Nobel
laureates, and other VIP’s.
Robert was very nervous.
He told [us] about
some experimental results which Ed Creutz had obtained earlier in the day
which indicated that the [Trinity] atom bomb would be a dud.
”2396
Oppenheimer searched for calm in the midst of this latest evidence of the
physical world’s relentlessness and found a breath of it in the Bhagavad-Gita,
the seven-hundred-stanza devotional poem interpolated into the great
Aryan epic Mahabharata at about the same time that Greece was declining
from its golden age.
He had discovered the Gita at Harvard; at Berkeley he
had learned Sanskrit from the scholar Arthur Ryder to set himself closer to
the original text and thereaer a worn pink copy occupied an honored place
on the bookshelf closest to his desk.
ere are meanings enough for a
lifetime in the Gita, dramatized as a dialogue between a warrior prince
named Arjuna and Krishna, the principal avatar of Vishnu (and Vishnu the
third member of the Hindu godhead with Brahma and Shiva—a Trinity
again).
Vannevar Bush records the particular meaning Oppenheimer
clutched that desperate Saturday in July:
His was a profoundly complex character....
So my comment will be brief.
I simply record a poem,
which he translated from the Sanscrit, and which he recited to me two nights before [Trinity]:2397
In battle, in forest, at the precipice in the mountains,
On the dark great sea, in the midst of javelins and arrows,
In sleep, in confusion, in the depths of shame,
e good deeds a man has done before defend him.
Back at Base Camp Oppenheimer slept no more than four hours that
night; Farrell heard him stirring restlessly on his bunk in the next room of
the quarters they shared, racked with coughing.
Chain-smoking as much as
meditative poetry drove him through his days.
Sturdy Hans Bethe found a way back from the precipice, Kistiakowsky
remembers:
Sunday morning another phone call came with wonderful news.
Hans Bethe spent the whole night
of Saturday analyzing the electromagnetic theory of this experiment and discovered that the
instrumental design was such that even a perfect implosion could not have produced oscilloscope
records different from what was observed.
So I became again acceptable to local high society.
2398
When Groves called, Oppenheimer chatted happily about the Bethe results.
e general interrupted: “What about the weather?” “e weather is
whimsical,” the whimsical physicist said.2399 e Gulf air mass had stagnated
over the test site.
But change was coming.
Jack Hubbard, the meteorologist,
predicted light and variable winds the next day.
Stagnation exacerbated the July heat.
Camera crews replacing battery
packs damaged by a blown circuit burned their hands on metal camera
housings.
Frank Oppenheimer, thin enough not to suffer the heat unduly,
hurried to construct a last-minute experiment less aloof than readings of
light and radiation: he set out boxes filled with excelsior and posts nailed
with corrugated iron strips to simulate the fragile Japanese houses where
LeMay’s ubiquitous drill presses lurked.
Groves had forbidden the
construction of full-scale housing for the test, more scientific tomfoolery, a
waste of money and time.
Norris Bradbury’s instructions for bomb assembly
as of Saturday listed “Gadget complete”; for “Sunday, 15 July, all day,” he
advised his crews to “look for rabbits’ feet and four-leaved clovers.
2400
Should we have the Chaplain down there?” Rabbits’ feet would turn up, but
even chaplains would have had trouble finding a stem of clover on the
Jornada.
Oppenheimer, Groves, Bainbridge, Farrell, Tolman and an Army
meteorologist met with Hubbard at McDonald Ranch at four that aernoon
to consider the weather.
Hubbard reminded them that he had never liked
the July 16 date.
He thought the shot could go as scheduled, he noted in his
journal, “in less than optimum conditions, which would require
sacrifices.
”2401 Groves and Oppenheimer repaired to another room to confer.
ey decided to wait and see.
ey had scheduled a last weather conference
for the next morning at 0200 hours; they would make up their minds then.
e shot was set for 0400 and they let that time stand.
Sometime early that evening Oppenheimer climbed the tower to perform
a final ritual inspection.2402 ere before him crouched his handiwork.
Its
bandages had been removed and it was hung now with insulated wires that
looped from junction boxes to the detonator plugs that studded its dark
bulk, an exterior ugly as Caliban’s.
His duty was almost done.
At dusk the tired laboratory director was calm.
He stood with Cyril Smith
beside the reservoir at McDonald Ranch where cattle had watered and spoke
of families and home, even of philosophy, and Smith found himself soothed.
A storm was blowing up.
Oppenheimer looked beneath it to anchorage, to
the darkening Oscuras.
“Funny how the mountains always inspire our
work,” the metallurgist heard him say.2403
With the weather changing from stagnant to violent and with everyone
short of sleep, moods swung at Base Camp.
e occasion of Fermi’s satire
that evening made Bainbridge furious.
It merely irritated Groves:
I had become a bit annoyed with Fermi...
when he suddenly offered to take wagers from his
fellow scientists on whether or not the bomb would ignite the atmosphere, and if so, whether it
would merely destroy New Mexico or destroy the world.
He had also said that aer all it wouldn’t
make any difference whether the bomb went off or not because it would still have been a well
worth-while scientific experiment.
For if it did fail to go off, we would have proved that an atomic
explosion was not possible.
2404
On the realistic grounds, the Italian laureate explained with his usual
candor, that the best physicists in the world would have tried and failed.
Bainbridge was furious because Fermi’s “thoughtless bravado” might scare
the soldiers, who did not have the benefit of a knowledge of thermonuclear
ignition temperatures and fireball cooling effects.2405 But a new force was
about to be loosed on the world; no one could be absolutely certain—Fermi’s
point—of the outcome of its debut.
Oppenheimer had assigned Edward
Teller the deliciously Tellerian task of trying to think of any imaginable trick
or turn by which the explosion might escape its apparent bounds.
Teller at
Los Alamos that evening raised the same question Fermi had, but
questioned Robert Serber, no mere uninformed GI:
Trying to find my way home in the darkness, I bumped into an acquaintance, Bob Serber.
at day we had received a memo from our director...
saying that we would have to be [at Trinity] well
before dawn, and that we should be careful not to step on a rattlesnake.
I asked Serber, “What will
you do tomorrow about the rattlesnakes?” He said, “I’ll take a bottle of whiskey.” 2406 I then went into my usual speech, telling him how one could imagine that things might get out of control in
this, that, or a third manner.
But we had discussed these things repeatedly, and we could not see
how, in actual fact, we could get into trouble.
en I asked him, “And what do you think about it?”
ere in the dark Bob thought for a moment, then said, “I’ll take a second bottle of whiskey.”
Rabi, the real mystic among them, spent the evening playing poker.
Bainbridge managed a little sleep.
He headed the Arming Party charged
with arming the bomb.
He was due at Zero by 11 P.M.
to prepare the shot.
An
MP sergeant woke him at ten; he picked up Kistiakowsky and Joseph
McKibben, the tall, lanky Missouri-born physicist responsible for running
the countdown, and assembled with Hubbard and his crew and two security
men.
“On the way in,” Bainbridge remembers, “I stopped at S 10,000 and
locked the main sequence timing switches.
Pocketing the key I returned to
the car and continued to Point Zero.” 2407 A young Harvard physicist, Donald
Hornig, was busy in the tower.
He had designed the 500-pound X-unit of
high-voltage capacitors that fired Fat Man’s multiple detonators with
microsecond simultaneity, a crucial Luis Alvarez invention, and now was
disconnecting the unit Bainbridge’s crews had used for practice runs and
connecting the new unit reserved for the shot.
In static test this Fat Man
would be fired through cables from the S-10000 control bunker; the one to
be shipped to Tinian, self-contained, would carry onboard batteries.
Cables
or batteries would charge the X-unit and on command it would discharge its
capacitors to the detonators, vaporizing wires imbedded in the explosive
blocks to start shock waves to set off the HE.
“Soon aer our arrival,” says
Bainbridge, “Hornig completed his work and returned to S 10,000.
Hornig
was the last man to leave the top of the tower.” 2408
Hubbard operated a portable weather station at the tower; to measure
wind speed and direction the two sergeants who worked with him inflated
and released helium balloons.
At eleven o’clock he found the wind blowing
across Zero toward N-10000.
At midnight the Gulf air mass had thickened
to 17,000 feet and arranged two inversions—cooler air above warmer—
within its layered depths that might loop the radioactive Trinity column
back down to the ground directly below.
To an observer traveling toward the desert from Los Alamos “the night
was dark with black clouds, and not a star could be seen.” 2409
understorms began lashing the Jornada at about 0200 hours on July 16,
drenching Base Camp and S-10000.
“It was raining cats and dogs, lightning
and thunder,” Rabi remembers.
“[We were] really scared [that] this object
there in the tower might be set off accidentally.
So you can imagine the
strain on Oppenheimer.” 2410 Winds gusted to thirty miles an hour.
Hubbard
hung on at Zero for last-minute readings—only misting drizzle had yet
reached the tower area—and arrived eight minutes late for the 0200 weather
conference at Base Camp, to find Oppenheimer waiting for him outside the
weather center there.
2411 Hubbard told him they would have to scrub 0400
but should be able to shoot between 0500 and 0600.
Oppenheimer looked
relieved.
Inside they found an agitated Groves waiting with his advisers.
“What the
hell is wrong with the weather?” the general greeted his forecaster.
2412
Hubbard took the opportunity to repeat that he had never liked July 16.
Groves demanded to know when the storm would pass.
Hubbard explained
its dynamics: a tropical air mass, night rain.
Aernoon thunderstorms took
their energy from the heating of the earth and collapsed at sunset; this one,
contrariwise, would collapse at dawn.
Groves growled that he wanted a
specific time, not an explanation.
I’m giving you both, Hubbard rejoined.
2413
He thought Groves was ready to cancel the shot, which seems unlikely given
the pressure from Potsdam.
He told Groves he could postpone if he wanted
but the weather would relent at dawn.
Oppenheimer applied himself to soothe his bulky comrade.
Hubbard was
the best man around, he insisted, and they ought to trust his forecast.
e
others at the meeting—Tolman and two Army meteorologists, one more
than before—agreed.
Groves relented.
“You’d better be right on this,” he
threatened Hubbard, “or I will hang you.” He ordered the meteorologist to
sign his forecast and set the shot for 0530.
en he went off to roust the
governor of New Mexico out of bed to the telephone to warn him he might
have to declare martial law.
Bainbridge at Zero was less concerned with local effects than with distant,
even though he had personally locked open the circuits that communicated
with the shelters.
“Sporadic rain was a disturbing factor,” he recalls.
“...
We
had none of the lightning reported by those at the Base Camp about 16,000
yards away or at S 10,000, but it made interesting conversation as many of
the wires from N, S, W 10,000 ended at the tower.
”2414 About 0330 a gust of
wind at Base Camp collapsed Vannevar Bush’s tent; he found his way to the
mess hall, where from 0345 the cooks began serving a breakfast of powdered
eggs, coffee and French toast.
e gods sent Emilio Segrè happier amusement.
He had distracted himself
through the evening with Andrè Gide’s e Counterfeiters and slept through
the worst of the Base Camp storm.
“But my attention was attracted by an
unbelievable noise whose nature escaped me completely.
As the noise
persisted, Sam Allison and I went out with a flashlight and, much to our
surprise, found hundreds of frogs in the act of making love in a big hole that
had filled with water.
”2415
Hubbard departed Base Camp at 0315 for S-10000.
e rain had moved
on.
He telephoned Zero; one of his men there said the clouds were opening
and a few stars shone.
By 0400 the wind was shiing toward the southwest,
away from the shelters.
e meteorologist prepared his final forecast at S-
10000.
He called Bainbridge at 0440.
“Hubbard gave me a complete weather
report,” the Trinity director recalls, “and a prediction that at 5:30 a.m.
the
weather at Point Zero would be possible but not ideal.
We would have
preferred no inversion layer at 17,000 feet but not at the expense of waiting
over half a day.
I called Oppenheimer and General Farrell to get their
agreement that 5:30 a.m.
would be T = 0.” 2416 Hubbard, Bainbridge,
Oppenheimer and Farrell each had veto over the shot.
ey all agreed.
Trinity would fire at 0530 hours July 16, 1945—just before dawn.
Bainbridge had arranged to report each step of the final arming process to
S-10000 in case anything went wrong.
“I drove McKibben to W 900 so that
he could throw the timing and sequence switches there while I checked off
his list.” Back at Zero Bainbridge called in the next step “and threw the
special arming switch which was not on McKibben’s lines.
Until this switch
was closed the bomb could not be detonated from S 10,000.
2417 e final
task was to switch on a string of lights on the ground which were to serve as
an ‘aiming point’ for a B-29 practice bombing run.
e Air Force wanted to
know what the blast effects would be like on a plane 30,000 feet up and some
miles away....
Aer turning on the lights, I returned to my car and drove to
S 10,000.” Kistiakowsky, McKibben and the security guards rode with him.
ey were the last to leave the site.
Behind them searchlight beams
converged on the tower.
e Arming Party arrived at S-10000, the earth-sheltered concrete control
bunker, at about 0508.
Hubbard gave Bainbridge his signed forecast.
“I
unlocked the master switches,” Bainbridge concludes, “and McKibben
started the timing sequence at –20 minutes, 5:09:45 a.m.
”2418 Oppenheimer
would watch the shot from S-10000, as would Farrell, Donald Hornig and
Samuel Allison.
With the beginning of the final countdown Groves le by
jeep for Base Camp.
For protection against common disaster he wanted to
be physically separated from Farrell and Oppenheimer.
Busloads of visitors from Los Alamos and beyond had begun arriving at
Compañia Hill, the viewing site twenty miles northwest of Zero, at 0200.
Ernest Lawrence was there, Hans Bethe, Teller, Serber, Edwin McMillan,
James Chadwick come to see what his neutron was capable of and a crowd of
other men, including Trinity staff no longer needed down on the plain.
“With the darkness and the waiting in the chill of the desert the tension
became almost unendurable,” one of them remembers.
2419 e shortwave
radio requisitioned to advise them of the schedule refused to work until aer
Allison began broadcasting the countdown.
Richard Feynman, a future
Nobel laureate who had entered physics as an adolescent via radio tinkering,
tinkered the radio to life.
Men began moving into position.
“We were told to
lie down on the sand,” Teller protests, “turn our faces away from the blast,
and bury our heads in our arms.
No one complied.
We were determined to
look the beast in the eye.” 2420 e radio went dead again and they were le
to watch for the warning rockets to be fired from S-10000.
“I wouldn’t turn
away...
but having made all those calculations, I thought the blast might be
rather bigger than expected.
So I put on some suntan lotion.
”2421 Teller
passed the lotion around and the strange prophylaxis disturbed one
observer: “It was an eerie sight to see a number of our highest-ranking
scientists seriously rubbing sunburn lotion on their faces and hands in the
pitch-blackness of the night, twenty miles from the expected flash.
”2422
e countdown continued at S-10000.
At 0525 a green Very rocket went
up.
at signaled a short wail of the siren at Base Camp.
Shallow trenches
had been bulldozed below the south rim of the Base Camp reservoir for
protection and since these men watched ten miles closer to Zero than the
crowd on Compañia Hill they planned to use them.
Rabi lay down next to
Kenneth Greisen, a Cornell physicist, facing south away from Zero.
Greisen
remembers that he was “personally nervous, for my group had prepared and
installed the detonators, and if the shot turned out to be a dud, it might
possibly be our fault.” 2423 Groves found refuge between Bush and Conant,
thinking “only of what I would do if, when the countdown got to zero,
nothing happened.” 2424 Victor Weisskopf remembers that “groups of
observers had arranged small wooden sticks at a distance of 10 yds from our
observation place in order to estimate the size of the explosion.” e sticks
were posted on the rim of the reservoir.
“ey were arranged so that their
[height] corresponded to 1000 .
at zero point.” 2425 Philip Morrison relayed
the countdown to the Base Camp observers by loudspeaker.
e two-minute-warning rocket fizzled.
A long wail of the Base Camp
siren signaled the time.
e one-minute warning rocket fired at 0529.
Morrison also meant to look the beast in the eye and lay down on the slope
of the reservoir facing Zero.
He wore sunglasses and held a stopwatch in one
hand and a piece of welder’s glass in the other.
e welder’s glass was
stockroom issue: Lincoln Super-visibility Lens, Shade #10.
At S-10000 someone heard Oppenheimer say, “Lord, these affairs are hard
on the heart.
”2426 McKibben had been marking off the minutes and Allison
broadcasting them.
At 45 seconds McKibben turned on a more precise
automatic timer.
“e control post was rather crowded,” Kistiakowsky notes,
“and, having now nothing to do, I le as soon as the automatic timer was
thrown in...
and went to stand on the earth mound covering the concrete
dugout.
(My own guess was that the yield would be about 1 kt [i.e., 1,000
tons, 1 kiloton], and so five miles seemed very safe.)” 2427
Teller prepared himself further at Compañia Hill: “I put on a pair of dark
glasses.
I pulled on a pair of heavy gloves.
With both hands I pressed the
welder’s glass to my face, making sure no stray light could penetrate around
it.
I then looked straight at the aim point.” 2428
Donald Hornig at S-10000 monitored a switch that could cut the
connection between his X-unit in the tower and the bomb, the last point of
interruption if anything went wrong.
At thirty seconds before T = 0 four red
lights flashed on the console in front of him and a voltmeter needle flipped
from le to right under its round glass cover to register the full charging of
the X-unit.
Farrell noticed that “Dr.
Oppenheimer, on whom had rested a
very heavy burden, grew tenser as the last seconds ticked off.
He scarcely
breathed.
He held on to a post to steady himself.
For the last few seconds, he
stared directly ahead.” 2429
At ten seconds a gong sounded in the control bunker.
e men lying in
their shallow trenches at Base Camp might have been laid out for death.
Conant told Groves he never imagined seconds could be so long.
Morrison
studied his stopwatch.
“I watched the second-hand until T =—5 seconds,” he
wrote the day of the shot, “when I lowered my head onto the sand bank in
such a way that a slight rise in the ground completely shielded me from
Zero.
2430 I placed the welding glass over the right lens of my sun glasses, the
le lens of which was covered by an opaque cardboard shield.
I counted
seconds and at zero began to raise my head just over the protecting rise.”
Ernest Lawrence on Compañia Hill had planned to watch the shot through
the windshield of a car, allowing the glass to filter out damaging ultraviolet,
“but at the last minute decided to get out...
(evidence indeed I was
excited!).
”2431 Robert Serber, his bottles of whiskey to succor him, stared
twenty miles toward distant Zero with unprotected eyes.
e last decisive
inaction was Hornig’s:
Now the sequence of events was all controlled by the automatic timer except that I had the knife
switch which could stop the test at any moment up until the actual firing...
I don’t think I have
ever been keyed up as I was during those final seconds...
I kept telling myself “the least flicker of
that needle and you have to act.” It kept on coming down to zero.2432 I kept saying, “Your reaction time is about half a second and you can’t relax for even a fraction of a second.”...
My eyes were
glued on the dial and my hand was on the switch.
I could hear the timer counting...
three...
two...
one.
e needle fell to zero....
Time: 0529:45.
e firing circuit closed; the X-unit discharged; the
detonators at thirty-two detonation points simultaneously fired; they ignited
the outer lens shells of Composition B; the detonation waves separately
bulged, encountered inclusions of Baratol, slowed, curved, turned inside out,
merged to a common inward-driving sphere; the spherical detonation wave
crossed into the second shell of solid fast Composition B and accelerated; hit
the wall of dense uranium tamper and became a shock wave and squeezed,
liquefying, moving through; hit the nickel plating of the plutonium core and
squeezed, the small sphere shrinking, collapsing into itself, becoming an
eyeball; the shock wave reaching the tiny initiator at the center and swirling
through its designed irregularities to mix its beryllium and polonium;
polonium alphas kicking neutrons free from scant atoms of beryllium: one,
two, seven, nine, hardly more neutrons drilling into the surrounding
plutonium to start the chain reaction.
en fission multiplying its
prodigious energy release through eighty generations in millionths of a
second, tens of millions of degrees, millions of pounds of pressure.
Before
the radiation leaked away, conditions within the eyeball briefly resembled
the state of the universe moments aer its first primordial explosion.
en expansion, radiation leaking away.
e radiant energy loosed by the
chain reaction is hot enough to take the form of so X rays; these leave the
physical bomb and its physical casing first, at the speed of light, far in front
of any mere explosion.
Cool air is opaque to X rays and absorbs them,
heating; “the very hot air,” Hans Bethe writes, “is therefore surrounded by a
cooler envelope, and only this envelope”—hot enough at that—“is visible to
observers at a distance.
”2433 e central sphere of air, heated by the X rays it
absorbs, reemits lower-energy X rays which are absorbed in turn at its
boundaries and reemitted beyond.
By this process of downhill leapfrogging,
which is known as radiation transport, the hot sphere begins to cool itself.
When it has cooled to half a million degrees—in about one ten-thousandth
of a second—a shock wave forms that moves out faster than radiation
transport can keep up.
“e shock therefore separates from the very hot,
nearly isothermal [i.e., uniformly heated] sphere at the center,” Bethe
explains.
2434 Simple hydrodynamics describes the shock front: like a wave in
water, like a sonic boom in air.
It moves on, leaving behind the isothermal
sphere confined within its shell of opacity, isolated from the outside world,
growing only slowly by radiation transport on this millisecond scale of
events.
What the world sees is the shock front and it cools into visibility, the first
flash, milliseconds long, of a nuclear weapon’s double flash of light, the
flashes too closely spaced to distinguish with the eye.
Further cooling
renders the front transparent; the world if it still has eyes to see looks
through the shock wave into the hotter interior of the fireball and “because
higher temperatures are now revealed,” Bethe continues, “the total radiation
increases toward a second maximum”: the second, longer flash.2435 e
isothermal sphere at the center of the expanding fireball continues opaque
and invisible, but it also continues to give up its energy to the air beyond its
boundaries by radiation transport.
at is, as the shock wave cools, the air
behind it heats.
A cooling wave moves in reverse of the shock wave, eating
into the isothermal sphere.
Instead of one simple thing the fireball is thus
several things at once: an isothermal sphere invisible to the world; a cooling
wave moving inward toward that sphere, eating away its radiation; a shock
front propagating into undisturbed air, air that has not yet heard the news.
Between each of these parts lay further intervening regions of buffering air.
Eventually the cooling wave eats the isothermal sphere completely away
and the entire fireball becomes transparent to its own radiation.
Now it cools
more slowly.
Below about 9000°F it can cool no more.
en, concludes
Bethe, “any further cooling can only be achieved by the rise of the fireball
due to its buoyancy, and the turbulent mixing associated with this rise.
is
is a slow process, taking tens of seconds.” 2436
e high-speed cameras at W-10000 recorded the later stages of the
fireball’s development, Bainbridge reports, tracking its huge swelling from
the eyeball it had been:
e expansion of the ball of fire before striking the ground was almost symmetric...
except for
the extra brightness and retardation of a part of the sphere near the bottom, a number of blisters,
and several spikes that shot radially ahead of the ball below the equator.
Contact with the ground
was made at 0.65 ms [i.e., thousandths of a second].
ereaer the ball became rapidly
smoother....
Shortly aer the spikes struck the ground (about 2 ms) there appeared on the ground
ahead of the shock wave a wide skirt of lumpy matter.
2437...
At about 32 ms [when the fireball had expanded to 945 feet in diameter] there appeared immediately behind the shock wave a dark
front of absorbing matter, which traveled slowly out until it became invisible at 0.85 s [the
expanding front about 2,500 feet across].
e shock wave itself became invisible [earlier] at about
0.10 s....
e ball of fire grew even more slowly to a [diameter] of about [2,000 feet], until the dust cloud
growing out of the skirt almost enveloped it.
e top of the ball started to rise again at 2 s.
At 3.5 s
a minimum horizontal diameter, or neck, appeared one-third of the way up the skirt, and the
portion of the skirt above the neck formed a vortex ring.
e neck narrowed, and the ring and fast-
growing pile of matter above it rose as a new cloud of smoke, carrying a convection stem of dust
behind it....
e stem appeared twisted like a le-handed screw.
But men saw what theoretical physics cannot notice and what cameras
cannot record, saw pity and terror.
Rabi at Base Camp felt menaced:
We were lying there, very tense, in the early dawn, and there were just a few streaks of gold in the
east; you could see your neighbor very dimly.
ose ten seconds were the longest ten seconds that I
ever experienced.
Suddenly, there was an enormous flash of light, the brightest light I have ever
seen or that I think anyone has ever seen.
It blasted; it pounced; it bored its way right through you.
It was a vision which was seen with more than the eye.
It was seen to last forever.
You would wish it
would stop; altogether it lasted about two seconds.
Finally it was over, diminishing, and we looked
toward the place where the bomb had been; there was an enormous ball of fire which grew and
grew and it rolled as it grew; it went up into the air, in yellow flashes and into scarlet and green.
It looked menacing.
It seemed to come toward one.
2438
A new thing had just been born; a new control; a new understanding of man, which man had
acquired over nature.
To Teller at Compañia Hill the burst “was like opening the heavy curtains
of a darkened room to a flood of sunlight.
”2439 Had astronomers been
watching they could have seen it reflected from the moon, literal
moonshine.
Joseph McKibben made a comparison at S-10000: “We had a lot of flood
lights on for taking movies of the control panel.
When the bomb went off,
the lights were drowned out by the big light coming in through the open
door in the back.
”2440
It caught Ernest Lawrence at Compañia Hill in the act of stepping from
his car: “Just as I put my foot on the ground I was enveloped with a warm
brilliant yellow white light—from darkness to brilliant sunshine in an
instant and as I remember I momentarily was stunned by the surprise.” 2441
To Hans Bethe at Compañia Hill “it looked like a giant magnesium flare
which kept on for what seemed a whole minute but was actually one or two
seconds.” 2442
Serber at Compañia Hill risked blindness but glimpsed an earlier stage of
the fireball:
At the instant of the explosion I was looking directly at it, with no eye protection of any kind.
I saw
first a yellow glow, which grew almost instantly to an overwhelming white flash, so intense that I
was completely blinded....
By twenty or thirty seconds aer the explosion I was regaining normal
vision....
e grandeur and magnitude of the phenomenon were completely breathtaking.2443
Segrè at Base Camp imagined apocalypse:
e most striking impression was that of an overwhelmingly bright light....
I was flabbergasted by
the new spectacle.
We saw the whole sky flash with unbelievable brightness in spite of the very
dark glasses we wore....
I believe that for a moment I thought the explosion might set fire to the
atmosphere and thus finish the earth, even though I knew that this was not possible.
2444
Not light but heat disturbed Morrison at Base Camp:
From ten miles away, we saw the unbelievably brilliant flash.
at was not the most impressive
thing.
We knew it was going to be blinding.
We wore welder’s glasses.
e thing that got me was
not the flash but the blinding heat of a bright day on your face in the cold desert morning.
It was
like opening a hot oven with the sun coming out like a sunrise.2445
It unfolded in silence, a ballistics expert watching from Compañia Hill
realized with awe:
e flash of light was so bright at first as to seem to have no definite shape, but aer perhaps half a
second it looked bright yellow and hemispherical with the flat side down, like a half-risen sun but
about twice as large.
Almost immediately a turgid rising of this luminous mass began, great swirls
of flame seeming to ascend within a rather rectangular outline which expanded rapidly in
height....
Suddenly out of the center of it there seemed to rise a narrower column to a
considerably greater height.
en as a climax, which was exceedingly impressive in spite of the fact
that the blinding brightness had subsided, the top of the slenderer column seemed to mushroom
out into a thick parasol of a rather bright but spectral blue....
All this seemed very fast...
and was
followed by a feeling of letdown that it was all over so soon.2446 en came the awe-inspiring realization that it was twenty miles away, that what had flared up and died so brilliantly and
quickly was really a couple of miles high.
e feeling of the remoteness of this thing which had
seemed so near was emphasized by the long silence while we watched the grey smoke grow into a
taller and taller twisting column, a silence broken aer a minute or so that seemed much longer by
a quite impressive bang, about like the crack of a five-inch anti-aircra gun at a hundred yards.
“Most experiences in life can be comprehended by prior experiences,”
Norris Bradbury comments, “but the atom bomb did not fit into any
preconceptions possessed by anybody.” 2447
As the fireball rose into the air, Joseph W.
Kennedy reports, “the overcast
of strato-cumulus clouds directly overhead [became] pink on the underside
and well illuminated, as at a sunrise.
”2448 Weisskopf noticed that “the path of
the shock wave through the clouds was plainly visible as an expanding circle
all over the sky where it was covered by clouds.” 2449 “When the red glow
faded out,” writes Edwin McMillan, “a most remarkable effect made its
appearance.
e whole surface of the ball was covered with a purple
luminescence, like that produced by the electrical excitation of the air, and
caused undoubtedly by the radioactivity of the material in the ball.” 2450
Fermi had prepared an order-of-magnitude experiment to determine
roughly the bomb’s yield:
About 40 seconds aer the explosion the air blast reached me.
I tried to estimate its strength by
dropping from about six feet small pieces of paper before, during and aer the passage of the blast
wave.
Since, at the time, there was no wind, I could observe very distinctly and actually measure
the displacement of the pieces of paper that were in the process of falling while the blast was passing.2451 e shi was about 2 ½ meters, which, at the time, I estimated to correspond to the blast that would be produced by ten thousand tons of T.N.T.
“From the distance of the source and from the displacement of the air due to
the shock wave,” Segrè explains, “he could calculate the energy of the
explosion.
is Fermi had done in advance having prepared himself a table
of numbers, so that he could tell immediately the energy liberated from this
crude but simple measurement.
”2452 “He was so profoundly and totally
absorbed in his bits of paper,” adds Laura Fermi, “that he was not aware of
the tremendous noise.” 2453
Frank Oppenheimer found his brother watching beside him outside the
control bunker at S-10000:
And so there was this sense of this ominous cloud hanging over us.
It was so brilliant purple, with
all the radioactive glowing.
And it just seemed to hang there forever.
Of course it didn’t.
It must
have been just a very short time until it went up.
It was very terrifying.
2454
And the thunder from the blast.
It bounced on the rocks, and then it went—I don’t know where
else it bounced.
But it never seemed to stop.
Not like an ordinary echo with thunder.
It just kept
echoing back and forth in that Jornada del Muerto.
It was a very scary time when it went off.
And I wish I would remember what my brother said, but I can’t—but I think we just said, “It
worked.” I think that’s what we said, both of us.
“It worked.”
Trinity director Bainbridge appropriately pronounced its benediction: “No
one who saw it could forget it, a foul and awesome display.” 2455
At Base Camp Groves “personally thought of Blondin crossing Niagara
Falls on his tightrope, only to me the tightrope had lasted for almost three
years, and of my repeated, confident-appearing assurances that such a thing
was possible and that we would do it.
”2456 Sitting up in their trenches before
the blast wave arrived, he and Conant and Bush ceremoniously shook hands.
e blast had knocked Kistiakowsky down at S-10000.
He scrambled up
to watch the fireball rise and darken and mushroom purple auras, then
moved to claim his bet.
“I slapped Oppenheimer on the back and said,
‘Oppie, you owe me ten dollars.’ ” 2457 e distracted Los Alamos director
searched his wallet.
“It’s empty,” he told Kistiakowsky, “you’ll have to
wait.
”2458 Bainbridge went around congratulating the S-10000 leaders on the
success of the implosion method.
“I finished by saying to Robert, ‘Now we
are all sons of bitches.’...
[He] told my younger daughter later that it was
the best thing anyone said aer the test.” 2459
“Our first feeling was one of elation,” Weisskopf remembers, “then we
realized we were tired, and then we were worried.
”2460 Rabi elaborates:
Naturally, we were very jubilant over the outcome of the experiment.
While this tremendous ball of
flame was there before us, and we watched it, and it rolled along, it became in time diffused with
the clouds....2461 en it was washed out with the wind.
We turned to one another and offered
congratulations, for the first few minutes.
en, there was a chill, which was not the morning cold; it was a chill that came to one when one thought, as for instance when I thought of my wooden
house in Cambridge, and my laboratory in New York, and of the millions of people living around
there, and this power of nature which we had first understood it to be—well, there it was.
Oppenheimer looked again into the Gita for a model sufficiently scaled:
We waited until the blast had passed, walked out of the shelter and then it was extremely solemn.
We knew the world would not be the same.
A few people laughed, a few people cried.
Most people
were silent.
I remembered the line from the Hindu scripture, the Bhagavad-Gita: Vishnu is trying
to persuade the Prince that he should do his duty and to impress him he takes on his multiarmed
form and says, “Now I am become Death, the destroyer of worlds.” I suppose we all thought that,
one way or another.
2462
Other models also came to mind, Oppenheimer told an audience shortly
aer the war:
When it went off, in the New Mexico dawn, that first atomic bomb, we thought of Alfred Nobel,
and his hope, his vain hope, that dynamite would put an end to wars.2463 We thought of the legend of Prometheus, of that deep sense of guilt in man’s new powers, that reflects his recognition of evil,
and his long knowledge of it.
We knew that it was a new world, but even more we knew that
novelty itself was a very old thing in human life, that all our ways are rooted in it.
e successful director of the Los Alamos bomb laboratory le with
Farrell in a jeep.
Rabi watched him arrive at Base Camp and saw a change:
He was in the forward bunker.
When he came back, there he was, you know, with his hat.
2464
You’ve seen pictures of Robert’s hat.
And he came to where we were in the headquarters, so to
speak.
And his walk was like “High Noon”—I think it’s the best I could describe it—this kind of
strut.
He’d done it.
“When Farrell came up to me,” Groves continues the story, “his first words
were, e war is over.’ My reply was, ‘Yes, aer we drop two bombs on Japan.’
I congratulated Oppenheimer quietly with ‘I am proud of you,’ and he
replied with a simple ‘ank you.’ ”2465 e theoretical physicist who was
also a poet, who found physics, as Bethe says, “the best way to do
philosophy,” had staked his claim on history.
2466 It was a larger claim, but
more ambivalent, than any Nobel Prize.
e horses in the MP stable still whinnied in fright; the paddles of the
dusty Aermotor windmill at Base Camp still spun away the energy of the
blast; the frogs had ceased to make love in the puddles.
Rabi broke out a
bottle of whiskey and passed it around.
Everyone took a swig.
Oppenheimer
went to work with Groves on a report for Stimson at Potsdam.
“My faith in
the human mind has been somewhat restored,” Hubbard overheard him
say.2467 He estimated the blast at 21,000 tons—21 kilotons.
2468 Fermi knew from his paper experiment that it was at least 10 KT.
Rabi had wagered 18.
Later that morning Fermi and Herbert Anderson would don white surgical
scrub suits and board the two lead-lined tanks to drive near Zero.
Fermi’s
tank broke down aer only a mile of approach and he had to walk back.
Anderson clanked on.
rough the periscope the young physicist studied
the crater the bomb had made.
e tower—the $20,000 winch, the shack,
the wooden platform, the hundred feet of steel girders—was gone, vaporized
down to the stubby twisted wreckage of its footings.
What had been asphalt
paving was now fused sand, green and translucent as jade.
e cup strung to
Anderson’s rocket scooped up debris.
His later radiochemical measurements
confirmed 18.6 KT.
2469 at was nearly four times what Los Alamos had
expected.
Rabi won the pot.
Fermi experienced a delayed reaction, he told his wife: “For the first time
in his life on coming back from Trinity he had felt it was not safe for him to
drive.
2470 It had seemed to him as if the car were jumping from curve to
curve, skipping the straight stretches in between.
He had asked a friend to
drive, despite his strong aversion to being driven.” Stanislaw Ulam, who
chose not to attend the shot, watched the buses returning: “You could tell at
once they had had a strange experience.
You could see it on their faces.
I saw
that something very grave and strong had happened to their whole outlook
on the future.
”2471
A bomb exploded in a desert damages not much besides sand and cactus
and the purity of the air.
Stafford Warren, the physician responsible for
radiological safety at Trinity, had to search to discover more lethal effects:
Partially eviscerated dead wild jack rabbits were found more than 800 yards from zero, presumably
killed by the blast.
A farm house three miles away had doors torn loose and suffered other
extensive damage....2472
e light intensity was sufficient at nine miles to have caused temporary blindness and this
would be longer lasting at shorter distances....
e light together with the heat and ultraviolet
radiation would probably cause severe damage to the unprotected eye at 5–6 miles; damage
sufficient to put personnel out of action several days if not permanently.
e boxes of excelsior Frank Oppenheimer had set out, and the pine
boards, also recorded the coming of the light: they were charred beyond
1,000 yards, slightly scorched up to 2,000 yards.
At 1,520 yards—ninetenths
of a mile—exposed surfaces had heated almost instantly to 750°F.
2473
William Penney, the British physicist who had studied blast effects for the
Target Committee, held a seminar at Los Alamos five days aer Trinity.
“He
applied his calculations,” Philip Morrison remembers.
“He predicted that
this [weapon] would reduce a city of three or four hundred thousand people
to nothing but a sink for disaster relief, bandages, and hospitals.
He made it
absolutely clear in numbers.
It was reality.
”2474
Around the time of the Trinity shot, in the predawn dark at Hunter’s Point
in San Francisco Bay, a floodlit crane had loaded onto the deck of the
Indianapolis the fieen-foot crate that carried the Little Boy gun assembly.
Two sailors carried aboard the Little Boy bullet in a lead bucket shouldered
between them on a crowbar.
ey followed the two Los Alamos Army
officers to the cabin of the ship’s flag lieutenant, who had vacated it for the
voyage.
Eyebolts had been welded to its deck.
e sailors strapped the lead
bucket to the eyebolts.
One of the officers padlocked it into place.
ey
would take turns guarding it around the clock for the tenday voyage to
Tinian.
At 0836 Pacific War Time, four hours aer the light flung from the
Jornada del Muerto blanched the face of the moon, the Indianapolis sailed
with its cargo under the Golden Gate and out to sea.2475
19
Tongues of Fire
At the end of March 1945, as Curtis LeMay’s bombers shuttled back and
forth burning cities, Colonel Elmer E.
Kirkpatrick, a plainspoken Army
engineer, arrived in the Marianas to locate a small corner where he could
lodge Paul Tibbets’ 509th Composite Group.2476 Kirkpatrick met with
LeMay and then with Pacific Fleet commander Chester Nimitz on Guam on
the day he arrived, March 30, and found the commanding officers
cooperative.
LeMay personally flew Kirkpatrick to Tinian on April 3.
e
next day, he reported to Groves, he “covered most of the island [and]
decided on our sites and the planning forces went to work on layouts.”
ough there was no shortage of B-29’s, he found that cement and buildings
were scarce; “housing and life here is a little rugged for everyone except
[general] officers & the Navy.
Tents or open barracks.” Kirkpatrick flew back
to Guam on April 5 “to dig up some materials some place” and “to get
authority for the work I required,” threaded his way through the Air Force
and Navy chains of command with his letters of authority from Washington
and by the end of the day had seen a telex sent to Saipan “directing them to
give me enough material to get the essential things done.” A Navy
construction battalion—the SeaBees—would build the buildings and
hardstands and dig the pits from which the bombs, too large for ground-
level clearance, would be lied up into the bomb bays of Tibbets’ B-29’s.
By early June, when Tibbets arrived to inspect the accommodations and
confer with LeMay, Kirkpatrick could report that “progress has been very
satisfactory and I have the feeling now that we can’t miss.” He sat in on an
evening meeting between Tibbets and LeMay and heard evidence that the
Twentieth Air Force commander did not yet appreciate the power of an
atomic bomb:
LeMay does not favor high altitude bombing.
Work is not as accurate but, more important,
visibility at such altitudes is extremely poor especially during the period June to November.
Tibbets advised him that the weapon would destroy a plane using it at an altitude of less than 25,000 feet.
Kirkpatrick demonstrated his progress to Groves with an impressive list:
five warehouses, an administration building, roads and parking areas and
nine magazines completed; pits completed except for lis; hardstands for
parking the 509th aircra completed except for asphalt paving; generator
buildings and compressor shed completed; one air-conditioned building
where the bombs would be assembled to be completed by July 1; two more
assembly buildings to be completed by August 1 and August 15.
Of the
509th’s men more than 1,100 had already staged out by ship “and more [are]
coming in every week.”
e first of Tibbets’ combat crews arrived June 10, flying themselves to
Tinian in advanced, specially modified new B-29’s.
e early-model aircra
delivered to the group the previous autumn had become obsolete, Tibbets
explained to readers of the Saturday Evening Post aer the war:
Tests showed us that the B-29’s we had weren’t good enough for atom bombing.
2477 ey were heavy, older types.
Top cylinders were overheating and causing valve failures in the long climb to
30,000 feet at 80 per cent of full power....
I asked for new, light-weight B-29’s and fuel-injection systems to replace carburetors.
He got those improvements and more: quick-closing pneumatic bomb
doors, fuel flow meters, reversible electric propellers.
e new aircra had been modified to accommodate the special bombs
they would carry and the added crew.
e cylindrical tunnel that connected
the pressurized forward and waist sections of the plane had to be partly cut
away and reworked so that the larger bomb, Fat Man, would fit in the
forward bomb bay.
Guide rails were installed to prevent the tail assemblies
from hanging up during fallout.
An extra table, chair, oxygen outlet and
interphone station for the weaponeers responsible for monitoring a bomb
during flight went in forward of the radio operator’s station in the forward
section.
“e performance of these special B-29’s was exceptional,” writes
the engineer in charge of their procurement.
“ey were without doubt the
finest B-29’s in the theater.
”2478 By the end of June, eleven of the new
bombers shone on their hardstands in the Pacific sun.2479
To men used to the blizzards and dust of Wendover, Utah, the 509th’s
historian claims, Tinian “looked like the Garden of Paradise.
”2480 e
surrounding blue ocean and the palm groves may have occasioned that
vision.
Philip Morrison, who came out aer Trinity to help assemble Fat
Man, saw more reverberantly what the island had become, as he told a
committee of U.S.
Senators later in 1945:
Tinian is a miracle.
Here, 6,000 miles from San Francisco, the United States armed forces have
built the largest airport in the world.
A great coral ridge was half-leveled to fill a rough plain, and
to build six runways, each an excellent 10-lane highway, each almost two miles long.
Beside these
runways stood in long rows the great silvery airplanes.
ey were there not by the dozen but by the
hundred.
From the air this island, smaller than Manhattan, looked like a giant aircra carrier, its
deck loaded with bombers....
And all these gigantic preparations had a grand and terrible outcome.
At sunset some day the
field would be loud with the roar of motors.
Down the great runways would roll the huge planes,
seeming to move slowly because of their size, but far outspeeding the occasional racing jeep.
One
aer another each runway would launch its planes.
Once every 15 seconds another B-29 would
become air-borne.
For an hour and a half this would continue with precision and order.
e sun
would go below the sea, and the last planes could still be seen in the distance, with running lights
still on.
Oen a plane would fail to make the take-off, and go skimming horribly into the sea, or
into the beach to burn like a huge torch.
We came oen to sit on the top of the coral ridge and
watch the combat strike of the 313th wing in real awe.
Most of the planes would return the next
morning, standing in a long single line, like beads on a chain, from just overhead to the horizon.
You could see 10 or 12 planes at a time, spaced a couple of miles apart.
As fast as the near plane
would land, another would appear on the edge of the sky.
ere were always the same number of
planes in sight.
e empty field would fill up, and in an hour or two all the planes would have
landed.
A resemblance in shape between Tinian and Manhattan had inspired the
SeaBees to name the island’s roads for New York City streets.2481 e 509th
happened to be lodged immediately west of North Field at 125th Street and
Eighth Avenue, near Riverside Drive, in Manhattan, the environs of
Columbia University where Enrico Fermi and Leo Szilard had identified
secondary neutrons from fission: the wheel had come full circle.
“e first half of July,” Norman Ramsey writes of 509th activity, “was
occupied with establishing and installing all of the technical facilities needed
for assembly and test work at Tinian.
”2482 In the meantime the group’s flight
crews practiced navigating to Iwo Jima and back and bombing with standard
general-purpose bombs and then with Pumpkins such bypassed islands still
nominally in Japanese hands as Rota and Truk.
* * *
Harry Truman and Jimmy Byrnes le suburban Potsdam in an open car to
tour ravaged Berlin at about the same time on July 16, 1945, that Groves and
Oppenheimer at Trinity were preparing their first report of the tower shot’s
success.
e Potsdam Conference, appropriately coded TERMINAL, was
supposed to have begun that aernoon, but Joseph Stalin was late arriving
by armored train from Moscow.
(He apparently suffered a mild heart attack
the previous day.) e Berlin tour gave Truman an opportunity to view at
close hand the damage Allied bombing and Red Army shelling had done.
Byrnes was officially Secretary of State now, invested in a sweltering
ceremony in the White House Rose Garden on July 3 attended by a crowd of
his former House, Senate and Supreme Court colleagues.
Aer Byrnes swore
the oath of office Truman had kidded him: “Jimmy, kiss the Bible.” 2483
Byrnes complied, then gave as good as he got: passed the Bible to the
President and bade him kiss it as well.
Truman did so; understanding the
byplay between the former Vice President and the man who had missed his
turn, the crowd laughed.
Four days later the two leaders boarded the cruiser
Augusta for the Atlantic crossing to Antwerp and now they rode side by side
into Berlin, conquerors in snap-brim hats and natty worsteds.
ough he had arrived before them in Potsdam, Henry Stimson did not
accompany the President and his favorite adviser on their tour.
e
Secretary of War had consulted with Truman the day before Byrnes’
swearing-in—proposing to give the Japanese “a warning of what is to come
and definite opportunity to capitulate”—and as he was leaving had asked the
President plaintively if he had not invited his Secretary of War to attend the
forthcoming conference out of solicitude for his health.
2484 at was it,
Truman had said quickly, and Stimson had replied that he could manage the
trip and would like to go, that Truman ought to have advice “from the top
civilians in our Department.” 2485 e next day, the day of Byrnes’ investiture,
Truman accorded the elderly statesman permission.
But Stimson had
traveled separately on the military transport Brazil via Marseilles, was
lodged separately in Potdam from the President and his Secretary of State
and would not be included in their daily private discussions.
One of
Stimson’s aides felt that “Secretary Byrnes was a little resentful of Mr.
Stimson’s presence there....
2486 e Secretary of the Navy wasn’t there so
why should Mr.
Stimson be there?” Byrnes in his 1947 account of his career,
Speaking Frankly, narrates an entire chapter about Potsdam without once
mentioning Stimson’s name, relegating his rival to a brief separate discussion
of the decision to use the atomic bomb on Japan and awarding him there the
dubious honor of having chosen the targets.
In fact, Stimson at Potsdam
would be reduced to serving Truman and Byrnes as not much more than a
messenger boy.
But the messages he brought were fateful.
“We reviewed the Second Armored Division,” Truman reports his Berlin
tour in his impromptu diary, “...
Gen.
[J.
H.] Collier, who seemed to know
his stuff, put us in a reconnaissance car built with side seats and no top, just
like a hoodlum wagon minus the top, or a fire truck with seats and no hose,
and we drove slowly down a mile and a half of good soldiers and some
millions of dollars worth of equipment—which had amply paid its way to
Berlin.
”2487 e destroyed city fired an uneasy burst of associations:
en we went on to Berlin and saw absolute ruin.
Hitler’s folly.
He overreached himself by trying
to take in too much territory.
He had no morals and his people backed him up.
Never did I see a
more sorrowful sight, nor witness retribution to the nth degree....
I thought of Carthage, Baalbec, Jerusalem, Rome, Atlantis; Peking, Babylon, Nineveh; Scipio,
Rameses II, Titus, Hermann, Sherman, Jenghis Khan, Alexander, Darius the Great.
But Hitler only
destroyed Stalingrad—and Berlin.
I hope for some sort of peace—but I fear that machines are
ahead of morals by some centuries and when morals catch up perhaps there’ll be no reason for any
of it.I hope not.
But we are only termites on a planet and maybe when we bore too deeply into the
planet there’ll be a reckoning—who knows?
e “Proposed Program for Japan” that Stimson had offered to Truman on
July 2 had reckoned up that country’s situation—which included the
possible entry of the Soviet Union, at present neutral, into the Pacific war—
and judged it desperate:2488
Japan has no allies.
Her navy is nearly destroyed and she is vulnerable to a surface and underwater blockade which
can deprive her of sufficient food and supplies for her population.
She is terribly vulnerable to our concentrated air attack upon her crowded cities, industrial and
food resources.
She has against her not only the Anglo-American forces but the rising forces of China and the
ominous threat of Russia.
We have inexhaustible and untouched industrial resources to bring to bear against her
diminishing potential.
We have great moral superiority through being the victim of her first sneak attack.
On the other hand, Stimson had argued, because of the mountainous
Japanese terrain and because “the Japanese are highly patriotic and certainly
susceptible to calls for fanatical resistance to repel an invasion,” America
would probably “have to go through with an even more bitter finish fight
than in Germany” if it attempted to invade.
Was there, then, any alternative?
Stimson thought there might be:
I believe Japan is susceptible to reason in such a crisis to a much greater extent than is indicated by our current press and other current comment.
Japan is not a nation composed wholly of mad
fanatics of an entirely different mentality from ours.
On the contrary, she has within the past
century shown herself to possess extremely intelligent people, capable in an unprecedentedly short
time of adopting not only the complicated technique of Occidental civilization but to a substantial
extent their culture and their political and social ideas.
Her advance in these respects...
has been
one of the most astounding feats of national progress in history....
It is therefore my conclusion that a carefully timed warning be given to Japan....
I personally think that if in [giving such a warning] we should add that we do not exclude a
constitutional monarchy under her present dynasty, it would substantially add to the chances of
acceptance.
Within the text of his proposal the Secretary of War several times
characterized it as “the equivalent of an unconditional surrender,” but others
did not see it so.
Before Byrnes le for Potsdam he had carried the
document to ailing Cordell Hull, a fellow Southerner and Franklin
Roosevelt’s Secretary of State from 1933 to 1944, and Hull had immediately
plucked out the concession to the “present dynasty”—the Emperor Hirohito,
in whose mild myopic figure many Americans had personified Japanese
militarism—and told Byrnes that “the statement seemed too much like
appeasement of Japan.” 2489
It may have been, but by the time they arrived in Potsdam, Stimson,
Truman and Byrnes had learned that it was also the minimum condition of
surrender the Japanese were prepared to countenance, whatever their
desperate situation.
U.S.
intelligence had intercepted and decoded messages
passing between Tokyo and Moscow instructing Japanese ambassador
Naotake Sato to attempt to interest the Soviets in mediating a Japanese
surrender.
“e foreign and domestic situation for the Empire is very
serious,” Foreign Minister Shigenori Togo had cabled Sato on July 11, “and
even the termination of the war is now being considered privately....
2490
We are also sounding out the extent to which we might employ the USSR in
connection with the termination of the war....
[is is] a matter with which
the Imperial Court is...
greatly concerned.” And pointedly on July 12:
It is His Majesty’s heart’s desire to see the swi termination of the war....
However, as long as
America and England insist on unconditional surrender our country has no alternative but to see
it through in an all-out effort for the sake of survival and the honor of the homeland.2491
Unconditional surrender seemed to the Japanese leadership a demand to
give up its essential and historic polity, a demand that under similar
circumstances Americans also might hesitate to meet even at the price of
their lives: hence Stimson’s careful qualification of his proposed terms of
surrender.
But to the extent that the imperial institution was tainted with
militarism, an offer to preserve it might also seem an offer to preserve the
militaristic government that ran the country and that had started and
pursued the war.
Certainly many Americans might think so and might
conclude in consequence that their wartime sacrifices were being callously
betrayed.
Hull considered these difficulties while Byrnes sailed the Atlantic and sent
along a cable of further advice on July 16.
e Japanese might reject a
challenge to surrender, the former Secretary of State argued, even if it
allowed the Emperor to remain on the throne.
In that case not only would
the militarists among them be encouraged by what they would take to be a
sign of weakening Allied will, but also “terrible political repercussions would
follow in the U.S....
Would it be well first to await the climax of Allied
bombing and Russia’s entry into the war?” 2492
e point of warning the Japanese was to encourage an early surrender in
the hope of avoiding a bloody invasion; the trouble with waiting until the
Soviet Union entered the war was that it le Truman where he had dangled
uncomfortably for months: over Stalin’s barrel, dependent on the USSR for
military intervention in Manchuria to tie up the Japanese armies there.
Hull’s delaying tactic might improve the first prospect; but it might also
secure the second.
Another message arrived in Potsdam that evening, however, that changed
the terms of the equation, a message for Stimson from George Harrison in
Washington announcing the success of the Trinity shot:
Operated on this morning.
Diagnosis not yet complete but results seem satisfactory and already
exceed expectations.
Local press release necessary as interest extends great distance.2493 Dr.
Groves pleased.
He returns tomorrow.
I will keep you posted.
“Well,” Stimson remarked to Harvey Bundy with relief, “I have been
responsible for spending two billions of dollars on this atomic venture.
Now
that it is successful I shall not be sent to prison in Fort Leavenworth.” 2494
Happily the Secretary of War carried the cable to Truman and Byrnes, just
returned to Potsdam from Berlin.
In Stimson’s welcome news Byrnes saw a more general reprieve.
It
informed his overnight response to Hull.
“e following day” Hull says, “I
received a message from Secretary Byrnes agreeing that the statement
[warning the Japanese] should be delayed and that, when it was issued, it
should not contain this commitment with regard to the Emperor.” 2495
Byrnes had good reason to delay a warning now: to await the readying of the
first combat atomic bombs.
ose weapons would answer Hull’s first
objection; if the Japanese ignored a warning, then the United States could
deliver a brutally retributive response.
With such weapons in the U.S.
arsenal unconditional surrender need not be compromised.
And America
no longer required the Soviet Union’s aid in the Pacific; the problem now
would be not dealing the Soviets in but stalling to keep them out.
“Neither
the President nor I,” Byrnes affirms, “were anxious to have them enter the
war aer we had learned of this successful test.
”2496
Byrnes and others within the American delegation came to realize that
preserving the Emperor might be sensible policy if Hirohito alone could
persuade the far-flung Japanese armies, undefeated and with a year’s supply
of ammunition on hand, to lay down their arms.2497 e new Secretary of
State, who was draing a suitable declaration, sought a formula that would
not arouse the American people but might reassure the Japanese.
e Joint
Chiefs produced its first version: “Subject to suitable guarantees against
further acts of aggression, the Japanese people will be free to choose their
own form of government.” 2498 e Japanese polity resided in the Imperial
House, not in the people, but provision for popular government was as
conditional an unconditional surrender as the enemy would be allowed.
George Harrison cabled Stimson on July 21 that “all your local military
advisors engaged in preparation definitely favor your pet city”: Groves still
coveted Kyoto.2499 Stimson quickly returned that he was “aware of no factors
to change my decision.
On the contrary new factors here tend to confirm
it.” 2500
Harrison also asked Stimson to alert him by July 25 “if [there is] any
change in plans” because “[the] patient [is] progressing rapidly.” 2501 At the
same time Groves requested permission from George Marshall to brief
Douglas MacArthur, who had not yet been told about the new weapon, in
view of “the imminence of the use of the atomic fission bomb in operations
against Japan, 5 to 10 August.
”2502, 2503 e 509th had begun flying Pumpkin missions over Japan the previous day for combat experience and to
accustom the enemy to small, unescorted flights of B-29’s at high altitude.
Groves’ eyewitness narrative of the Trinity test had arrived that Saturday
just before noon.
Stimson sought out Truman and Byrnes and had the
satisfaction of riveting them to their chairs by reading it aloud.
Groves
estimated “the energy generated to be in excess of the equivalent of 15,000 to
20,000 tons of TNT” and allowed his deputy, omas F.
Farrell, to call the
visual effects “unprecedented, magnificent, beautiful, stupendous and
terrifying.” Kenneth Bainbridge’s “foul and awesome display” became at
Farrell’s hand “that beauty the great poets dream about but describe most
poorly and inadequately,” which Farrell presumably meant for a superlative.
“As to the present war,” Farrell opined, “there was a feeling that no matter
what else might happen, we now had the means to insure its speedy
conclusion and save thousands of American lives.” Stimson saw that Truman
was “tremendously pepped up” by the report.
“[He] said it gave him an
entirely new feeling of confidence.” 2504
e President met the next day to discuss Groves’ results with Byrnes,
Stimson and the Joint Chiefs, including Marshall and Hap Arnold.
Arnold
had long maintained that conventional strategic bombing by itself could
compel the Japanese to surrender.
In late June, when invasion was being
decided, he had rushed LeMay to Washington to work the numbers.
LeMay
figured he could complete the destruction of the Japanese war machine by
October 1.
2505 “In order to do this,” writes Arnold, “he had to take care of
some 30 to 60 large and small cities.
”2506 Between May and August LeMay
took care of fiy-eight.2507 But Marshall disagreed with the Air Force
assessment.
e situation in the Pacific, he had told Truman in June, was
“practically identical” to the situation in Europe aer Normandy.
“Airpower
alone was not sufficient to put the Japanese out of the war.
2508 It was unable
alone to put the Germans out.” He explained his reasoning at Potsdam to an
interviewer aer the war:
We regarded the matter of dropping the [atomic] bomb as exceedingly important.2509 We had just gone through a bitter experience at Okinawa [the last major island campaign, when the Americans
lost more than 12,500 men killed and missing and the Japanese more than 100,000 killed in eighty-
two days of fighting].
is had been preceded by a number of similar experiences in other Pacific
islands, north of Australia.
e Japanese had demonstrated in each case they would not surrender and they would fight to the death....
It was expected that resistance in Japan, with their home ties,
would be even more severe.
We had had the one hundred thousand people killed in Tokyo in one
night of [conventional] bombs, and it had had seemingly no effect whatsoever.
It destroyed the
Japanese cities, yes, but their morale was not affected as far as we could tell, not at all.
So it seemed
quite necessary, if we could, to shock them into action....
We had to end the war; we had to save
American lives.
Before Groves’ report arrived, Dwight Eisenhower, a hard and pragmatic
commander, had angered Stimson with a significantly different assessment.
“We’d had a nice evening together at headquarters in Germany,” the Supreme
Allied Commander remembers, “nice dinner, everything was fine.
en
Stimson got this cable saying the bomb had been perfected and was ready to
be dropped.” 2510 e cable was the second Harrison had sent, the day aer
the Trinity test when Groves arrived back in Washington:
Doctor has just returned most enthusiastic and confident that the little boy is as husky as his big
brother.
e light in his eyes discernible from here to Highhold and I could have heard his screams
from here to my farm.
2511
Highhold was Stimson’s Long Island estate, 250 miles from Washington—
the Trinity flash had been visible even farther from Zero than that.
Harrison’s farm was 50 miles outside the capital.
Eisenhower found the
allegorical code less than amusing and the subject baleful:
e cable was in code, you know the way they do it.
“e lamb is born” or some damn thing like
that.
So then he told me they were going to drop it on the Japanese.
Well, I listened, and I didn’t
volunteer anything because, aer all, my war was over in Europe and it wasn’t up to me.
But I was
getting more and more depressed just thinking about it.
en he asked for my opinion, so I told
him I was against it on two counts.
First, the Japanese were ready to surrender and it wasn’t
necessary to hit them with that awful thing.
Second, I hated to see our country be the first to use
such a weapon.
Well...
the old gentleman got furious.
And I can see how he would.
Aer all, it
had been his responsibility to push for all the huge expenditure to develop the bomb, which of
course he had a right to do, and was right to do.
Still, it was an awful problem.2512
Eisenhower also spoke to Truman, but the President concurred in
Marshall’s judgment, having already formed his own.
“Believe Japs will fold
up before Russia comes in,” he confided to his diary almost as soon as he
heard of the Trinity success.
“I am sure they will when Manhattan appears
over their homeland.
”2513
When to issue the Potsdam Declaration now became essentially a
question of when the first atomic bombs would be ready to be dropped.
Stimson queried Harrison, who responded on July 23:
Operation may be possible any time from August 1 depending on state of preparation of patient
and condition of atmosphere.
From point of view of patient only, some chance August 1 to 3, good
chance August 4 to 5 and barring unexpected relapse almost certain before August 10.2514
Stimson had also asked for a target list, “always excluding the particular
place against which I have decided.
My decision has been confirmed by
highest authority.
”2515 Harrison complied: “Hiroshima, Kokura, Niigata in
order of choice here.
”2516
Which meant that Nagasaki had not yet, as of the last full week in July,
been added to the list.
Within days it would be.
Official Air Force historians
speculate that LeMay’s staff proposed it.
2517 e requirement for visual
bombing was probably the reason.
Hiroshima was 440 miles southwest of
Niigata.
Nagasaki, over the mountains from Kokura on Kyushu, was a
further 220 miles southwest of Hiroshima.
If one city was socked in, another
might be clear.
Nagasaki was certainly also added because it was one of the
few major cities le in Japan that had not yet been burned out.
A revealing third cable completed the day’s communications from
Harrison (the metallurgists at Los Alamos had finished the Pu core for Fat
Man that day).
It concerned possible future deliveries of atomic bombs and
hinted at a forthcoming change in design, probably to the so-called “mixed”
implosion bomb with a core of U235 and plutonium alloyed together.
Such a
core could draw on the resources of both Oak Ridge and Hanford:
First one of tested type [i.e., Fat Man] should be ready at Pacific base about 6 August.
Second one
ready about 24 August.
Additional ones ready at accelerating rate from possibly three in September
to we hope seven or more in December.
e increased rate above three per month entails changes
in design which Groves believes thoroughly sound.2518
Stimson reported Harrison’s several estimates to Truman on Tuesday
morning, July 24.
e President was pleased and said he would use them to
time the release of the Potsdam Declaration.
e Secretary took advantage
of the moment to appeal to Truman to consider assuring the Japanese
privately that they could keep their Emperor if they persisted in making that
concession a condition of surrender.
Deliberately noncommittal, the
President said he had the point in mind and would take care of it.
Stimson le and Byrnes joined Truman for lunch.
ey discussed how to
tell Stalin as little as possible about the atomic bomb.
Truman wanted
protective cover when Stalin learned that his wartime allies had developed
an epochal new weapon behind his back but wanted to give as little as
possible away.
Byrnes also devised a more immediate reason for
circumspection, he told the historian Herbert Feis in 1958:
As a result of his experience with the Russians during the first week of the Conference he had come to the conclusion that it would be regrettable if the Soviet Union entered the [Pacific] war,
and...
he was afraid that if Stalin were made fully aware of the power of the new weapon, he
might order the Soviet Army to plunge forward at once.
2519
But in fact Stalin already knew about the Trinity test.2520 His agents in the
United States had reported it to him.
It appears he was not immediately
impressed.
ere is gallows humor in Truman’s elaborately oand approach
to the Soviet Premier at the end of that day’s plenary session at the
Cecilienhof Palace, stripped and shabby, where pale German mosquitoes
homing through unscreened windows dined on the sanguinary conquerors.
Truman le behind his translator, rounded the baize-covered conference
table and sidled up to his Soviet counterpart, both men dissimulating.
“I
casually mentioned to Stalin that we had a new weapon of unusual
destructive force.
e Russian Premier showed no special interest.
All he
said was that he was glad to hear it and hoped we would make ‘good use of it
against the Japanese.’ ” 2521 “at,” concludes Robert Oppenheimer dryly,
knowing how much at that moment the world lost, “was carrying casualness
rather far.
”2522
If Stalin was not yet impressed with the potential of the bomb, Truman in
his private diary was waxing apocalyptic, biblical visions mingling in his
autodidact’s mind with doubt that the atom could be decomposed and
denial that the new weapon would be used to slaughter civilians:
We have discovered the most terrible bomb in the history of the world.
2523 It may be the fire destruction prophesied in the Euphrates Valley Era, aer Noah and his fabulous Ark.
Anyway we “think” we have found a way to cause a disintegration of the atom.
An experiment
in the New Mexican desert was startling—to put it mildly....
is weapon is to be used against Japan between now and August 10th.
I have told the Sec.
of
War, Mr.
Stimson, to use it so that military objectives and soldiers and sailors are the target and not
women and children.
Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader
of the world for the common welfare cannot drop this terrible bomb on the old Capital or the new.
He & I are in accord.
e target will be a purely military one and we will issue a warning statement asking the Japs to surrender and save lives.
I’m sure they will not do that, but we will
have given them the chance.
It is certainly a good thing for the world that Hitler’s crowd or Stalin’s
did not discover this atomic bomb.
It seems to be the most terrible thing ever discovered, but it can
be made the most useful.
e Tuesday Truman mentioned the new weapon to Stalin the Combined
Chiefs met with their Soviet counterparts; Red Army chief of staff General
Alexei E.
Antonov announced that Soviet troops were assembling on the
Manchurian border and would be ready to attack in the second half of
August.
Stalin had said August 15 before.
Byrnes was anxious that the
Soviets might prove uncharacteristically punctual.
at aernoon in Washington Groves draed the historic directive
releasing the atomic bomb to use.
2524 It passed up through Harrison for
transmission by radio EYES ONLY to Marshall “in order that your approval
and the Secretary of War’s approval might be obtained as soon as
possible.” 2525 (A small map of Japan cut from a large National Geographic
Society map and a one-page description of the chosen targets, which now
included Nagasaki, followed by courier.) Marshall and Stimson approved the
directive at Potsdam and presumably showed it to Truman, though it does
not record his formal authorization; it went out the next morning to the new
commander of the Strategic Air Force in the Pacific:
To General Carl Spaatz, CG, USASTAF:
1.
e 509 Composite Group, 20th Air Force will deliver its first special bomb as soon as weather
will permit visual bombing aer about 3 August 1945 on one of the targets: Hiroshima, Kokura,
Niigata and Nagasaki....
2.
Additional bombs will be delivered on the above targets as soon as made ready by the project
staff....
3.
Dissemination of any and all information concerning the use of the weapon against Japan is
reserved to the Secretary of War and the President of the United States....
4.
e foregoing directive is issued to you by direction and with the approval of the Secretary of
War and of the Chief of Staff, USA.
As Groves draed the directive the metallurgists at Los Alamos finished
casting the rings of U235 that fitted together to form the gun bomb’s target
assembly, the last components needed to complete Little Boy.
Strategy and delivery intersected on July 26 and synchronized.
e
Indianapolis arrived at Tinian.
ree Air Transport Command C-54 cargo
planes departed Kirtland Air Force Base with the three separate pieces of the
Little Boy target assembly; two more ATC C-54’s departed with Fat Man’s
initiator and plutonium core.
2526 Meanwhile Truman’s staff released the
Potsdam Declaration to the press at 7 P.M.
2527 for dispatch from Occupied
Germany at 9:20.
It offered on behalf of the President of the United States,
the President of Nationalist China and the Prime Minister of Great Britain
to give Japan “an opportunity to end this war”:
Following are our terms.
We will not deviate from them.
ere are no alternatives.
We shall brook
no delay.
ere must be eliminated for all time the authority and influence of those who have deceived
and misled the people of Japan into embarking on world conquest....
Until such a new order is established...
points in Japanese territory...
shall be occupied....
Japanese sovereignty shall be limited to the islands of Honshu, Hokkaido, Kyushu, Shikoku
and such minor islands as we determine.
e Japanese military forces, aer being completely disarmed, shall be permitted to return to
their homes with the opportunity to lead peaceful and productive lives.
We do not intend that the Japanese shall be enslaved as a race or destroyed as a nation, but stern
justice shall be meted out to all war criminals....
Freedom of speech, of religion, and of thought,
as well as respect for the fundamental human rights shall be established.
Japan shall be permitted to maintain such industries as will sustain her economy....
e occupying forces of the Allies shall be withdrawn from Japan as soon as these objectives
have been accomplished and there has been established in accordance with the freely expressed
will of the Japanese people a peacefully inclined and responsible government.
We call upon the government of Japan to proclaim now the unconditional surrender of all
Japanese armed forces....
e alternative for Japan is prompt and utter destruction.
“We faced a terrible decision,” Byrnes wrote in 1947.
“We could not rely
on Japan’s inquiries to the Soviet Union about a negotiated peace as proof
that Japan would surrender unconditionally without the use of the bomb.
In
fact, Stalin stated the last message to him had said that Japan would ‘fight to
the death rather than accept unconditional surrender.’ Under the
circumstances, agreement to negotiate could only arouse false hopes.
Instead, we relied upon the Potsdam Declaration.” 2528
e text of that somber document went out by radio to the Japanese from
San Francisco; Japanese monitors picked it up at 0700 hours Tokyo time July
27.2529 e Japanese leaders debated its mysteries all day.
A quick Foreign
Office analysis noted for the ministers that the Soviet Union had preserved
its neutrality by not sponsoring the declaration, that it specified what the
Allies meant by unconditional surrender and that the term itself had been
applied specifically only to the nation’s armed forces.
Foreign Minister Togo
disliked the demand for occupation and the stripping away of Japan’s foreign
possessions; he recommended waiting for a Soviet response to Ambassador
Sato’s representations before responding.
e Prime Minister, Baron Kantaro Suzuki, came during the day to the
same position.
e military leaders disagreed.
ey recommended
immediate rejection.
Anything less, they argued, might impair morale.
e next day Japanese newspapers published a censored version of the
Potsdam text, leaving out in particular the provision allowing disarmed
military forces to return peacefully to their homes and the assurance that the
Japanese would not be enslaved or destroyed.
In the aernoon Suzuki held a
press conference.
“I believe the Joint Proclamation by the three countries,”
he told reporters, “is nothing but a rehash of the Cairo Declaration.
As for
the Government, it does not find any important value in it, and there is no
other recourse but to ignore it entirely and resolutely fight for the successful
conclusion of the war.
”2530 In Japanese Suzuki said there was no other
recourse but to mokusatsu the declaration, which could also mean “treat it
with silent contempt.” Historians have debated for years which meaning
Suzuki had in mind, but there can hardly be any doubt about the rest of his
statement: Japan intended to fight on.
“In the face of this rejection,” Stimson explained in Harper’s in 1947, “we
could only proceed to demonstrate that the ultimatum had meant exactly
what it said when it stated that if the Japanese continued the war, ‘the full
application of our military power, backed by our resolve, will mean the
inevitable and complete destruction of the Japanese armed forces and just as
inevitably the utter devastation of the Japanese homeland.’ For such a
purpose the atomic bomb was an eminently suitable weapon.” 2531
e night of Suzuki’s press conference the five C-54’s from Albuquerque
arrived at Tinian, six thousand miles nearer Japan, while three B-29’s
departed Kirtland each carrying a Fat Man high-explosive preassembly.
2532
e U.S.
Senate in the meantime ratified the United Nations Charter.
e Indianapolis had sailed on to Guam aer unloading the Little Boy gun
and bullet at Tinian on July 26; from Guam it continued unescorted toward
Leyte in the Philippines, where two weeks of training would ready the crew,
1,196 men, to join Task Force 95 at Okinawa preparing for the November 1
Kyushu invasion.
2533 With the destruction of the Japanese surface fleet and
air force, unescorted sailing had become commonplace on courses through
rear areas, but the Indianapolis, an older vessel, lacked sonar gear for
submarine detection and was top-heavy.
Japanese submarine 1–58
discovered the heavy cruiser in the Philippine Sea a little before midnight on
Sunday, July 29, and mistook it for a battleship.
Easily avoiding detection
while submerging to periscope depth, 1–58 fired a fanwise salvo of six
torpedoes from 1,500 yards.
Lieutenant Commander Mochitsura
Hashimoto, 1–58’s commanding officer, remembers the result:
I took a quick look through the periscope, but there was nothing else in sight.
Bringing the boat on
to a course parallel with the enemy, we waited anxiously.
Every minute seemed an age.
en on the
starboard side of the enemy by the forward turret, and then by the aer turret there rose columns
of water, to be followed immediately by flashes of bright red flame.
en another column of water
rose from alongside Number 1 turret and seemed to envelop the whole ship—“A hit, a hit!” I
shouted as each torpedo struck home, and the crew danced round with joy....
Soon came the
sound of a heavy explosion, far greater than that of the actual hits.
ree more heavy explosions
followed in quick succession, then six more.2534
e torpedoes and following explosions of ammunition and aviation fuel
ripped away the cruiser’s bow and destroyed its power center.
Without
power the radio officer was unable to send a distress signal—he went
through the motions anyway—or the bridge to communicate with the
engine room.
e engines pushed the ship forward unchecked, scooping up
water through the holes in the hull and leaving behind the sailors thrown
overboard who had been sleeping on deck in the tropical heat.
e order to
abandon ship, when it came, had to be passed by word of mouth.
With the ship listing to 45 degrees frightened and injured men struggled
to follow disaster drill.
Fires lit the darkness and smoke sickened.
e ship’s
medical officer found some thirty seriously burned men in the port hangar
where the aviation fuel had exploded; at best they got morphine for their
screams and rough kapok lifejackets strapped on over their burns.
ey
went overboard with the others into salt water scummed with nauseating
fuel oil.
It was possible to walk down the hull to the keel and jump into the
water but the spinning number three screw with its lethal blades chopped to
death the unwary.
Some 850 men escaped.
e stern rose up a hundred feet straight into the
air and the ship plunged.
e survivors heard screams from within the
disappearing hull.
en they were le to the night and the darkness in
twelve-foot swells.
Most had kapok lifejackets.
Few had found their way to life ras.
ey
floated instead in clusters, linked together, stronger men swimming the
circumferences to catch sleepers before they dried away; one group
numbered between three and four hundred souls.
ey pushed the wounded
to the center where the water was calmer and prayed the distress call had
gone out.
e captain had found two empty life ras and later that night
encountered one more occupied.
He ordered the ras lashed together.
ey
sheltered ten men and he thought them the only survivors.
rough the
night a current carried the swimmers southwest while wind blew the ras
northeast; by the light of morning ras and swimmers had separated beyond
discovery.
More than fiy injured swimmers died during the night.
eir comrades
freed them from their jackets in the morning and let them go.
e wind
abated and the sun glared from the oil slick, blinding them with painful
photophobia.
And then the sharks came.
A seaman swimming for a floating
crate of potatoes thrashed in the water and was gone.
Elemental terror: the
men pressed together in their groups, some clusters deciding to beat the
water, some to hang immotile as flotsam.
A shark snapped away both a
sailor’s legs and his unbalanced torso, suspended in its lifejacket, flipped
upside down.
One survivor remembered counting twenty-five deadly
attacks; the ship’s doctor in his larger group counted eighty-eight.
ey won no rescue.
ey passed through Monday and Monday night and
Tuesday and Tuesday night without water, sinking lower and lower in the
sea as the kapok in their lifejackets waterlogged.
Eventually the thirstcrazed
drank seawater.
“ose who drank became maniacal and thrashed violently,”
the doctor testifies, “until the victims became comatose and drowned.” 2535
e living were blinded by the sun; their lifejackets abraded their ulcerating
skin; they burned with fever; they hallucinated.
Wednesday and Wednesday night.
e sharks circled and darted in to
foray aer flesh.2536 Men in the grip of group delusions followed one
swimmer to an island he thought he saw, another to the ghost of the ship,
another down into the ocean depths where fountains of fresh water seemed
to promise to slake their thirst; all were lost.
Fights broke out and men
slashed each other with knives.
Saturated lifejackets with waterlogged knots
dragged other victims to their deaths.
“We became a mass of delirious,
screaming men,” says the doctor grimly.
ursday morning, August 2, a Navy plane spotted the survivors.
Because
of negligence at Leyte the Indianapolis had not yet even been missed.
A
major rescue effort began, ships steaming to the area, PBY’s and PBM’s
dropping food and water and survival gear.
e rescuers found 318 naked
and emaciated men.
e fresh water they drank, one of them remembers,
tasted “so sweet [it was] the sweetest thing in your life.
”2537 rough the 84-
hour ordeal more than 500 men had died, their bodies feeding sharks or lost
to the depths of the sea.
Aer making good his escape, submarine commander Hashimoto
reminisces, “at length, on the 30th, we celebrated our haul of the previous
day with our favorite rice with beans, boiled eels, and corned beef (all of it
tinned).” 2538
e day of the I-58’s feast of canned goods Carl Spaatz telexed
Washington with news:
HIROSHIMA ACCORDING TO PRISONER OF WAR REPORTS IS THE ONLY ONE OF FOUR
TARGET CITIES...
THAT DOES NOT HAVE ALLIED PRISONER OF WAR CAMPS.2539
It was too late to reconsider targets, prisoners of war or not.
Washington
telexed back the next day:
TARGETS ASSIGNED...
REMAIN UNCHANGED.
HOWEVER IF YOU CONSIDER YOUR
INFORMATION RELIABLE HIROSHIMA SHOULD BE GIVEN FIRST PRIORITY AMONG
THEM.
e die was cast.
Once Trinity proved that the atomic bomb worked, men discovered reasons
to use it.
e most compelling reason Stimson stated in his Harper’s apologia
in 1947:
My chief purpose was to end the war in victory with the least possible cost in the lives of the men
in the armies which I had helped to raise.
In the light of the alternatives which, on a fair estimate,
were open to us I believe that no man, in our position and subject to our responsibilities, holding
in his hands a weapon of such possibilities for accomplishing this purpose and saving those lives, could have failed to use it and aerwards looked his countrymen in the face.2540
e Scientific Panel of the Interim Committee—Lawrence, Compton,
Fermi, Oppenheimer—had been asked to conjure a demonstration of
sufficient credibility to end the war.
Meeting at Los Alamos on the weekend
of June 16–17, debating long into the night, it found in the negative.
Even
Fermi’s ingenuity was not sufficient to the task of devising a demonstration
persuasive enough to decide the outcome of a long and bitter conflict.
Recognizing “our obligation to our nation to use the weapons to help save
American lives in the Japanese war,” the panel first surveyed the opinions of
scientific colleagues and then stated its own:2541
ose who advocate a purely technical demonstration would wish to outlaw the use of atomic
weapons, and have feared that if we use the weapons now our position in future negotiations will
be prejudiced.
Others emphasize the opportunity of saving American lives by immediate military
use, and believe that such use will improve the international prospects, in that they are more
concerned with the prevention of war than with the elimination of this specific weapon.
We find
ourselves closer to these latter views; we can propose no technical demonstration likely to bring an
end to the war; we see no acceptable alternative to direct military use.
e bomb was to prove to the Japanese that the Potsdam Declaration
meant business.
It was to shock them to surrender.
It was to put the Russians
on notice and serve, in Stimson’s words, as a “badly needed equalizer.
”2542 It
was to let the world know what was coming: Leo Szilard had dallied with
that rationale in 1944 before concluding in 1945 on moral grounds that the
bomb should not be used and on political grounds that it should be kept
secret.
Teller revived a variant rationale in early July 1945, in replying to
Szilard about a petition Szilard was then circulating among Manhattan
Project scientists protesting the bomb’s impending use:
First of all let me say that I have no hope of clearing my conscience.2543 e things we are working on are so terrible that no amount of protesting or fiddling with politics will save our souls....
But I am not really convinced of your objections.
I do not feel that there is any chance to outlaw
any one weapon.
If we have a slim chance of survival, it lies in the possibility to get rid of wars.
e
more decisive the weapon is the more surely it will be used in any real conflicts and no agreements
will help.
Our only hope is in getting the facts of our results before the people.
is might help to
convince everybody that the next war would be fatal.
For this purpose actual combat-use might
even be the best thing.
e bomb was also to be used to pay for itself, to justify to Congress the
investment of $2 billion, to keep Groves and Stimson out of Leavenworth
prison.
“To avert a vast, indefinite butchery,” Winston Churchill summarizes in
his history of the Second World War, “to bring the war to an end, to give
peace to the world, to lay healing hands upon its tortured peoples by a
manifestation of overwhelming power at the cost of a few explosions,
seemed, aer all our toils and perils, a miracle of deliverance.
”2544
e few explosions did not seem a miracle of deliverance to the civilians
of the enemy cities upon whom the bombs would be dropped.
In their
behalf—surely they have claim—something more might be said about
reasons.
e bombs were authorized not because the Japanese refused to
surrender but because they refused to surrender unconditionally.
e
debacle of conditional peace following the First World War led to the
demand for unconditional surrender in the Second, the earlier conflict
casting its dark shadow down the years.
“It was the insistence on
unconditional surrender that was the root of all evil,” writes the Oxford
moralist G.
E.
M.
Anscombe in a 1957 pamphlet opposing the awarding of
an honorary degree to Harry Truman.
2545 “e connection between such a
demand and the need to use the most ferocious methods of warfare will be
obvious.
And in itself the proposal of an unlimited objective in war is stupid
and barbarous.”
As before in the Great War for every belligerent, that was what the Second
World War had become: stupid and barbarous.
“For men to choose to kill
the innocent as a means to their ends,” Anscombe adds bluntly, “is always
murder, and murder is one of the worst of human actions....
In the
bombing of [Japanese] cities it was certainly decided to kill the innocent as a
means to an end.” In the decision of the Japanese militarists to arm the
Japanese people with bamboo spears and set them against a major invasion
force to fight to the death to preserve the homeland it was certainly decided
to kill the innocent as a means to an end as well.
2546
e barbarism was not confined to the combatants or the general staffs.
It
came to permeate civilian life in every country: in Germany and Japan, in
Britain, in Russia, certainly in the United States.
It was perhaps the ultimate
reason Jimmy Byrnes, the politician’s politician, and Harry Truman, the man
of the people, felt free to use and compelled to use a new weapon of mass
destruction on civilians in undefended cities.
“It was the psychology of the
American people,” I.
I.
Rabi eventually decided.
“I’m not justifying it on
military grounds but on the existence of this mood of the military with the
backing of the American people.” e mood, suggests the historian Herbert
Feis, encompassed “impatience to end the strain of war blended with a zest
for victory.
ey longed to be done with smashing, burning, killing, dying—
and were angry at the defiant, crazed, useless prolongation of the ordeal.” 2547
In 1945 Life magazine was the preeminent general-circulation magazine
in the United States.
It served millions of American families for news and
entertainment much as television a decade later began to do.
Children read
it avidly and reported on its contents in school.
In the last issue of Life before
the United States used the atomic bomb a one-page picture story appeared,
titled, in 48-point capitals, A JAP BURNS.
2548 Its brief text, for those who could
tear their eyes away from the six postcard-sized black-and-white
photographs showing a man being burned alive long enough to read the
words, savored horror while complaining of ugly necessity:
When the 7th Australian Division landed near Balikpapan on the island of Borneo last month they
found a town strongly defended by Japanese.
As usual, the enemy fought from caves, from
pillboxes, from every available hiding place.
And, as usual, there was only one way to advance
against them: burn them out.
Men of the 7th, who had fought the Japs before, quickly applied their
flamethrowers, soon convinced some Japs that it was time to quit.
Others, like the one shown here,
refused.
So they had to be burned out.
Although men have fought one another with fire from time immemorial, the flamethrower is
easily the most cruel, the most terrifying weapon ever developed.
If it does not suffocate the enemy
in his hiding place, its quickly licking tongues of flame sear his body to a black crisp.
But so long as
the Jap refuses to come out of his holes and keeps killing, this is the only way.
In a single tabloid page Life had assembled a brutal allegory of the later
course of the Pacific war.
Little Boy was ready on July 31.
It lacked only its four sections of cordite
charge, a precaution prepared when the weapon was designed at Los Alamos
but decided upon at Tinian, for safety on takeoff and in the event visual
bombing proved impossible, in which case Tibbets had orders to bring the
bomb back.
2549, 2550, 2551 ree of Tibbets’ full complement of fieen B-29’s flew a last test that last day of July with a dummy Little Boy.
ey took off
from Tinian, rendezvoused over Iwo Jima, returned to Tinian, dropped unit
L6 into the sea and practiced their daredevil diving turn.
“With the
completion of this test,” writes Norman Ramsey, “all tests preliminary to
combat delivery of a Little Boy with active material were completed.” 2552
at unit would be number Lll, and the sturdy tungsten-steel target holder
screwed to its muzzle, the best in stock, was the first one Los Alamos had
received; it had served four times for firing tests at Anchor Ranch late in
1944 before being packed in cosmoline for the voyage out to Tinian.
Since everything was ready, Farrell telexed Groves to report that the
mission could be flown on August 1; he would assume that the Spaatz
directive of July 25 authorized such initiative unless Groves replied to the
contrary.
2553 e commanding general of the Manhattan Project let his
deputy’s interpretation stand.
Little Boy would have flown on August 1 if a
typhoon had not approached Japan that day to intervene.
So the mission waited on the weather.
On August 2, ursday, the three B-
29’s that carried Fat Man preassemblies arrived from New Mexico.2554 e
assembly team of Los Alamos scientists and military ordnance technicians
went to work immediately to prepare one Fat Man for a drop test and a
second with higher-quality HE castings for combat.
2555 e third
preassembly would be held in reserve for the plutonium core scheduled to
be shipped from Los Alamos in mid-August.
“By August 3,” recalls Paul
Tibbets, “we were watching the weather and comparing it to the [long-
range] forecast.
e actual and forecast weather were almost identical, so we
got busy.
”2556
Among other necessities, getting busy involved briefing the crews of the
seven 509th B-29’s that would fly the first mission for weather reporting,
observation and bombing.
Tibbets scheduled the briefing for 1500 hours on
August 4.
e crews arrived between 1400 and 1500 to find the briefing hut
completely surrounded by MP’s armed with carbines.
Tibbets walked in
promptly at 1500; he had just returned from checking out the aircra he
intended to use to deliver Little Boy, usually piloted by Robert Lewis: B-29
number 82, as yet unnamed.
Deke Parsons joined him on the briefing
platform.
A radio operator, Sergeant Abe Spitzer, kept an illegal diary of his
experiences at Tinian that describes the briefing.
2557
e moment had arrived, Tibbets told the assembled crews.
e weapon
they were about to deliver had recently been tested successfully in the
United States; now they were going to drop it on the enemy.
Two intelligence officers undraped the blackboards behind the 509th
commander to reveal aerial photographs of the targets: Hiroshima, Kokura,
Nagasaki.
(Niigata was excluded, apparently because of weather.) Tibbets
named them and assigned three crews—“finger crews”—to fly ahead the day
of the drop to assess their cloud cover.
Two more aircra would accompany
him to photograph and observe; the seventh would wait beside a loading pit
on Iwo Jima as a spare in case Tibbets’ plane malfunctioned.
e 509th commander introduced Parsons, who wasted no words.
He told
the crews the bomb they were going to drop was something new in the
history of warfare, the most destructive weapon ever made: it would
probably almost totally destroy an area three miles across.
ey were stunned.
“It is like some weird dream,” Spitzer mused,
“conceived by one with too vivid an imagination.”
Parsons prepared to show a motion picture of the Trinity test.
e
projector refused to start.
en it started abruptly and began chewing up
leader.
Parsons told the projectionist to shut the machine off and
improvised.
He described the shot in the Jornada del Muerto: how far away
the light had been seen, how far away the explosion had been heard, the
effects of the blast wave, the formation of the mushroom cloud.
He did not
identify the source of the weapon’s energy, but with details—a man knocked
down at 10,000 yards, men 10 and 20 miles away temporarily blinded—he
won their rapt attention.
Tibbets took over again.
ey were now the hottest crews in the Air Force,
he warned them.
He forbade them to write letters home or to discuss the
mission even among themselves.
He briefed them on the flight.
It would
probably go, he said, early on the morning of August 6.
An air-sea rescue
officer described rescue operations.
Tibbets closed with a challenge, a final
word Spitzer paraphrases in his diary:
e colonel began by saying that whatever any of us, including himself, had done before was small
potatoes compared to what we were going to do now.
en he said the usual things, but he said
them well, as if he meant them, about how proud he was to have been associated with us, about
how high our morale had been, and how difficult it was not knowing what we were doing, thinking
maybe we were wasting our time and that the “gimmick” was just somebody’s wild dream.
He was
personally honored and he was sure all of us were, to have been chosen to take part in this raid,
which, he said—and all the other big-wigs nodded when he said it—would shorten the war by at
least six months.
And you got the feeling that he really thought this bomb would end the war,
period.
e following morning, Sunday, Guam reported that weather over the
target cities should improve the next day.
“At 1400 on August 5,” Norman
Ramsey records, “General LeMay officially confirmed that the mission
would take place on August 6.
”2558
at aernoon the loading crew winched Little Boy onto its sturdy
transport dolly, draped it with a tarpaulin to protect it from prying eyes—
there were still Japanese soldiers hiding out on the island, hunted at night by
security forces like raccoons—and wheeled it to one of the 13 by 16-foot
loading pits Kirkpatrick had prepared.
A battery of photographers followed
along to record the proceedings.
e dolly was wheeled over the nine-foot
pit on tracks; the hydraulic li came up to relieve it of its bomb and
detachable cradle; the crew wheeled the dolly away, removed the tracks,
rotated the bomb 90 degrees and lowered it into the pit.2559
e world’s first combat atomic bomb looked like “an elongated trash can
with fins,” one of Tibbets’ crew members thought.
2560 With its tapered tail
assembly that culminated in a boxed frame of stabilizing baffle plates it was
10½ feet long and 29 inches in diameter.
It weighed 9,700 pounds, an
armored cylinder jacketed in blackened dull steel with a flat, rounded nose.
A triple fusing system armed it.
e main fusing component was a radar
unit adapted from a tail-warning mechanism developed to alert combat
pilots when enemy aircra approached from behind.
“is radar device,”
notes the Los Alamos technical history, “would close a relay [i.e., a switch] at
a predetermined altitude above the target.” 2561 For reliability Little Boy and
Fat Man each carried four such radar units, called Archies.
Rather than an
approaching enemy aircra, the bomb Archies would bounce their signals
off the approaching enemy ground.
An agreed reading by any two of the
units would send a firing signal into the next stage of the fusing system, the
technical history explains:
is stage consisted of a bank of clock-operated switches, started by arming wires which were
pulled out of the clocks when the bomb dropped from the plane’s bomb bay.
ese clock switches
were not closed until 15 seconds aer the bomb was released.
eir purpose was to prevent
detonation in case the A[rchie] units were fired by signals reflected from the plane.
A second
arming device was a [barometric] pressure switch, which did not close until subject to a pressure
corresponding to 7000 feet altitude.
Once it passed through the clock and barometric arming devices the Little
Boy firing signal went directly to the primers that lit the cordite charges to
fire the gun.
Externally the fusing system revealed itself in trailing whips of
radar antennae, clock wires threaded into holes in the weapon’s upper waist
and holes in its tapered tail assembly that admitted external air to guarantee
accurate barometry.
Loading the bomb was delicate: the fit was tight.
A ground crew towed the
B-29 to a position beside the loading pit, running onto a turntable the main
landing gear on the wing nearer the pit.
Towing the aircra around on the
turntable through 180 degrees positioned it over the pit.
e hydraulic li
raised Little Boy to a point directly below the open bomb doors.
A plumb
bob hung from the single bomb shackle for a point of reference and jacks
built into the bomb cradle allowed the crew to line up the bomb eye.
“e operation can be accomplished in 20 to 25 minutes,” a Boeing
engineer commented in an August report, “but is a rather ticklish procedure,
as there is very little clearance with the catwalks and, once installed, nothing
holds the bomb but the single shackle and adjustable sway braces bearing on
it.” 2562
ough he flew it as his own, Robert Lewis had never named B-29
number 82.
e day of the loading Tibbets consulted the officers in Lewis’
crew—but not Lewis—and did so.
e 509th commander chose not pinups
or puns but his mother’s given names, Enola Gay, because she had assured
him he would not be killed flying when he fought out with his father his
decision to become a pilot.
“rough the years,” Tibbets told an interviewer
once, “whenever I got in a tight spot in a plane I always remembered her
calm assurance.
It helped.
In getting ready for the big one I rarely thought of
what might happen, but when I did, those words of Mom’s put an end to it.”
He “wrote a note on a slip of paper,” located a sign painter among the service
personnel—the man had to be dragged away from a soball game—and told
him to “paint that on the strike ship, nice and big.” 2563, 2564 Foot-high, squared brushstrokes went on at a 30-degree angle beneath the pilot’s
window of the bullet-nosed plane, the middle name flushright below the
first.
Lewis, a sturdy, combative two-hundred-pounder, had known for a day or
two that Tibbets would pilot the mission, a disappointment, but still
considered the special B-29 his own.
When he dropped by late in the
aernoon to inspect it and found ENOLA GAY painted on its fuselage he was
furious.
“What the hell is that doing on my plane?” one of his crew mates
remembers him yelling.2565 He found out that Tibbets had authorized the
christening and marched off to confront him.
e 509th commander told
him coolly, rank having its privileges, that he didn’t think the junior officer
would mind.
Lewis minded, but he could do no more than stow away his
resentment for the war stories he would tell.
“By dinnertime on the fih,” Tibbets narrates, “all [preparations were]
completed.
2566 e atom bomb was ready, the planes were gassed and
checked.
Takeoff was set for [2:45] a.m.
I tried to nap, but visitors kept me
up.
[Captain eodore J.] Dutch [Van Kirk, the Enola Gay’s navigator,]
swallowed two sleeping tablets, then sat up wide awake all night playing
poker.” e weapon waiting in the bomb bay took its toll on nerves.
“Final briefing was at 0000 of August 6,” Ramsey notes—midnight.
2567
Tibbets emphasized the power of the bomb, reminded the men to wear the
polarized goggles they had been issued, cautioned them to obey orders and
follow their protocols.
A weather officer predicted moderate winds with
clouds over the targets clearing at dawn.
Tibbets called forward a Protestant
chaplain who delivered a prayer composed for the occasion on the back of
an envelope; it asked the Almighty Father “to be with those who brave the
heights of y heaven and who carry the battle to our enemies.” 2568
Aer the midnight briefing the crews ate an early breakfast of ham and
eggs and Tibbets’ favorite pineapple fritters.
Trucks delivered them to their
hardstands.
At the Enola Gay’s hardstand, writes Ramsey, “amid brilliant
floodlights, pictures were taken and retaken by still and motion picture
photographers (as though for a Hollywood premiere).
”2569 A photograph
shows ten of the twelve members of the strike plane’s crew posed in flight
coveralls under the forward fuselage by the nose wheel: boyish Van Kirk in
overseas cap with his coveralls unzipped down his chest to expose a white T-
shirt; Major omas Ferebee, the bombardier, a handsome Errol Flynn copy
with an Errol Flynn mustache, resting a friendly hand on Van Kirk’s
shoulder; Tibbets standing at the center of it all easily smiling, belted and
trim, his hands in his pockets; at Tibbets’ le Robert Lewis, the only crew
member wearing a weapon; small, wiry Lieutenant Jacob Beser beside Lewis
awkwardly smiling, a Jewish technician from Baltimore added for the flight,
responsible for electronic countermeasures to screen the Archie units from
Japanese radar.
In front of the officers kneel the slimmer, mostly younger
enlisted men (though the entire flight crew was young, Tibbets now all of
thirty years old): radar operator Sergeant Joseph Stiborik; tail gunner Staff
Sergeant Robert Caron, Brooklyn-born, wearing a Dodgers baseball cap;
radio operator Private Richard R.
Nelson; assistant engineer Sergeant Robert
H.
Shumard; flight engineer Staff Sergeant Wyatt Duzenbury, thirty-two, a
former Michigan tree surgeon who thought the bomb looked like a tree
trunk.
An eleventh member of the crew, 2nd Lieutenant Morris Jeppson, an
ordnance expert, would assist Deke Parsons in arming and monitoring Little
Boy.
Parsons, the twelh man, resisted photographing but was flying the
mission as weaponeer.
e three weather planes and the Iwo Jima standby had already le.
Tibbets ordered Wyatt Duzenbury to start engines at 0227 hours.
Pilot and
copilot sat side by side just back of the point where the cylindrical fuselage
began to curve inward to form the bullet-shaped nose; Ferebee, the
bombardier, sat a step down ahead of them within the nose itself, an
exposed position but a good view.
Almost everything inside the aircra was
painted a dull lime green.
“It was just another mission,” Tibbets says, “if you
didn’t let imagination run away with your wits.
”2570 As Dimples Eight Two,
the Enola Gay’s unlikely designation that day, he reconstructs his dialogue
with the Tinian control tower:
I forgot the atom bomb and concentrated on the cockpit check.
I called the tower.
“Dimples Eight Two to North Tinian Tower.
Taxi-out and take-off
instructions.”
“Dimples Eight Two from North Tinian Tower.
Take off to the east on Runway A for Able.”
At the end of the runway, another call to the tower and a quick response: “Dimples Eight Two
cleared for take-off.”
Bob Lewis called off the time.
Fieen seconds to go.
Ten seconds.
Five seconds.
Get ready.
At that moment the Enola Gay weighed 65 tons.
It carried 7,000 gallons of
fuel and a four-ton bomb.
It was 15,000 pounds overweight.
Confident the
aircra was maintained too well to falter, Tibbets decided to use as much of
the two-mile runway as he needed to build RPM’s and manifold pressure
before roll-up.
He eased the brakes at 0245, the four fuel-injected Wright Cyclone
engines pounding.
“e B-29 has lots of torque in take-off,” he notes.
“It
wants to swerve off the runway to the le.
e average mass-production
pilot offsets torque by braking his right wheels.
It’s a rough ride, you lose ten
miles an hour and you delay the take-off.” Nothing so crude for Tibbets.
“Pilots of the 509th Group were taught to cancel torque by leading in with
the le engines, advancing throttles ahead of the right engines.
At eighty
miles an hour, you get full rudder control, advance the right-hand engines to
full power and, in a moment, you’re airborne.” 2571 Takeoff needed longer
than a moment for the Enola Gay’s overloaded flight.
As the runway
disappeared beneath the big bomber Lewis fought the urge to pull back the
yoke.
At the last possible takeoff point he thought he did.
Not he but Tibbets
did and abruptly they were flying, an old dream of men, climbing above a
black sea.
Ten minutes later they crossed the northern tip of Saipan on a course
northwest by north at 4,700 feet.2572 e air temperature was a balmy 72°.
ey were flying low not to burn fuel liing fuel and for the comfort of the
two weaponeers, Parsons and Jeppson, who had to enter the unpressurized,
unheated bomb bay to finish assembling the bomb.
at work began at 0300.
It was demanding in the cramped confines of
the loaded bomb bay but not dangerous; there was only minimal risk of
explosion.
e green plugs that blocked the firing signal and prevented
accidental detonation were plugged into the weapon; Parsons confirmed that
fact first of all.
Next he removed a rear plate; removed an armor plate
beneath, exposing the cannon breech; inserted a wrench into the breech
plug and rotated the wrench about sixteen times to unscrew the plug;
removed it and placed it carefully on a rubber pad.
He inserted the four
sections of cordite one at a time, red ends to breech.2573 He replaced the
breech plug and tightened it home, connected the firing line, reinstalled the
two metal plates and with Jeppson’s help removed and secured the tools and
the catwalk.
Little Boy was complete but not yet armed.
e charge loading
took fieen minutes.
ey spent another fieen minutes checking
monitoring circuitry at the panel installed at the weaponeer’s position in the
forward section.
en, except for monitoring, their work was done until
time to arm the bomb.
Robert Lewis kept a journal of the flight.
William L.
Lawrence, the New
York Times science editor attached to the Manhattan Project, had traveled
out to Tinian expecting to go along.
When he learned to his bitter
disappointment that his participation had been deleted he asked Lewis to
take notes.
e copilot imagined himself writing a letter to his mother and
father but appears to have sensed that the world would be looking over his
shoulder and styled his entries with regulation Air Force bonhomie.
“At
forty-five minutes out of our base,” he began self-consciously, “everyone is at
work.
2574 Colonel Tibbets has been hard at work with the usual tasks that
belong to the pilot of a B-29.
Captain Van Kirk, navigator, and Sergeant
Stiborik, radio operator, are in continuous conversation, as they are shooting
bearings on the northern Marianas and making radar wind runs.” No
mention of Parsons or Jeppson, oddly enough, though Lewis could have
seen the bomb hanging in its bay through the round port below the tunnel
opening straight back from his copilot’s seat.
e automatic pilot, personified as George, was flying the plane, which
Tibbets stationed below 5,000 feet.
e commander realized he was tired,
Lewis records: “e colonel, better known as ‘the Old Bull,’ shows signs of a
tough day.2575 With all he’s had to do to get this mission off, he is deserving
of a few winks, so I’ll have a bite to eat and look aer ‘George.’ ”
Rather than sleep Tibbets crawled through the thirty-foot tunnel to chat
with the waist crew, wondering if they knew what they were carrying.
“A
chemist’s nightmare,” the tail gunner, Robert Caron, guessed, then “a
physicist’s nightmare.” 2576 “Not exactly,” Tibbets hedged.
Tibbets was leaving
by the time Caron put two and two together:
[Tibbets] stayed...
a little longer, and then started to crawl forward up the tunnel.
I remembered
something else, and just as the last of the Old Man was disappearing, I sort of tugged at his foot,
which was still showing.
He came sliding back in a hurry, thinking maybe something was wrong.
“What’s the matter?”
I looked at him and said, “Colonel, are we splitting atoms today?”
is time he gave me a really funny look, and said, “at’s about it.”
Caron’s third try, which he styles “a lucky guess,” apparently decided
Tibbets to complete the crew’s briefing; back in his seat he switched on the
interphone, called “Attention!” and remembers saying something like “Well,
boys, here’s the last piece of the puzzle.” 2577 ey carried an atomic bomb, he
told them, the first to be dropped from an airplane.
ey were not physicists;
they understood at least that the weapon was different from any other ever
used in war.
Lewis took control from George to weave his way through a mass of
towering cumuli, clouds black in the darkness that swept aside to reveal a
sky shot with stars.
“At 4:30,” he jotted, “we saw signs of a late moon in the
east.2578 I think everyone will feel relieved when we have le our bomb with
the Japs and get half way home.
Or, better still, all the way home.” Ferebee in
the nose was quiet; Lewis suspected he was thinking of home, “in the
midwest part of old U.S.A.” e bombardier was in fact from Mocksville,
North Carolina, close enough to the Midwest for a native of New York.
Dawn lightening a little past 0500 cheered them; “it looks at this time,” Lewis
wrote coming out of the clouds, “that we will have clear sailing for a long
spell.”
At 0552 they approached Iwo Jima and Tibbets began climbing to 9,300
feet to rendezvous with the observation and photography planes.
e Enola
Gay circled le over Iwo, found its two escorts and moved on, its course
continuing northwest by north toward the archipelago of green islands the
men called the Empire.
“Aer leaving Iwo we began to pick up some low stratus,” Lewis resumes
his narrative, “and before long we were flying on top of an undercast.
At
07:10 the undercast began to break up a little bit.
Outside of a high thin
cirrus and the low stuff it’s a very beautiful day.
We are now about two hours
from Bombs Away.” 2579 ey flew into history through a middle world,
suspended between sky and sea, drinking coffee and eating ham sandwiches,
engines droning, the smell of hot electronics in the air.
At 0730 Parsons visited the bomb bay for the last time to arm Little Boy,
exchanging its green plugs for red and activating its internal batteries.
Tibbets was about to begin the 45-minute climb to altitude.
Jeppson worked
his console.
Parsons told Tibbets that Little Boy was “final.” Lewis overheard:
e bomb was now independent of the plane.
It was a peculiar sensation.
I had a feeling the bomb
had a life of its own now that had nothing to do with us.
I wished it were over and we were at this
same position on the way back to Tinian.2580
“Well, folks, it won’t be long now,” the copilot added as Tibbets increased
power to climb.2581
e weather plane at Hiroshima reported in at 0815 (0715 Hiroshima
time).
It found two-tenths cloud cover lower and middle and two-tenths at
15,000 feet.
e other two target weather reports followed.
“Our primary is
the best target,” Lewis wrote enthusiastically, “so, with everything going well
so far, we will make a bomb run on Hiroshima.” 2582 “It’s Hiroshima,” Tibbets
announced to the crew.2583
ey leveled at 31,000 feet at 0840.
ey had pressurized the aircra and
heated it against an outside temperature of –10°F.
Ten minutes later they
achieved landfall over Shikoku, the smaller home island east of Hiroshima, a
city which looks southeastward from the coast of Honshu into the Inland
Sea.
“As we are approaching our target, Ferebee, Van Kirk and Stiborik are
coming into their own, while the colonel and I are standing by and giving
the boys what they need.” 2584 Correcting course, Lewis means, aligning the
plane.
He got excited then or busy: “ere will be a short intermission while
we bomb our target.” But bombing the target was the main event.
e crew pulled on heavy flak suits, cumbersome protection the pilots
disdained.
No Japanese fighters came up to meet them, nor were they
bothered by flak.
e two escort planes dropped back to give the Enola Gay room.
Tibbets
reminded his men to wear their protective goggles.
ey carried no maps.
ey had studied aerial photographs and knew the
target city well.
It was distinctive in any case, sited on a delta divided by the
channels of seven distributaries.
“Twelve miles from the target,” Tibbets
remembers, “Ferebee called, ‘I see it!’ He clutched in his bombsight and took
control of the plane from me for a visual run.2585 Dutch [Van Kirk] kept
giving me radar course corrections.
He was working with the radar
operator....
I couldn’t raise them on the interphone to tell them Ferebee
had the plane.” e bombardier flew the plane through his bombsight, the
knurled knobs he adjusted instructing the automatic pilot to make minor
corrections in course.
ey crossed the Inland Sea on a heading only five
degrees south of due west.
Van Kirk noticed eight large ships south of them
in Hiroshima harbor.
e Enola Gay’s ground speed then was 285 knots,
about 328 miles per hour.
Above a fork in the ta River in central Hiroshima a T-shaped bridge
spanned the river and connected to the island formed by the two
distributaries.
e Aioi Bridge, not a war plant surrounded by workers’
houses, was Ferebee’s chosen aiming point.
Second Army headquarters was
based nearby.
Tibbets had called the bridge the most perfect AP he’d seen in
the whole damn war:2586
Ferebee had the dri well killed but the rate was off a little.2587 He made two slight corrections.
A loud “blip” on the radio notified the escort B-29’s that the bomb would drop in two minutes.2588
Aer that, Tom looked up from his bombsight and nodded to me; it was going to be okay.
He motioned to the radio operator to give the final warning.
A continuous tone signal went out,
telling [the escorts]: “In fieen seconds she goes.”
e distant weather planes also heard the radio signal.
So did the spare B-
29 parked on Iwo Jima.
It alerted Luis Alvarez in the observation plane to
prepare to film the oscilloscopes he had installed there; the radiolinked
parachute gauges he had designed to measure Little Boy’s explosive yield
hung in the bomb bay waiting to drop with the bomb and float down toward
the city.
Hiroshima unrolled east to west in the cross hairs of omas Ferebee’s
Norden bombsight.
e bomb-bay doors were open.
Ferebee had flown
sixty-three combat missions in Europe before returning to the United States
to instruct and then to join the 509th.
Before the war he had wanted to be a
baseball player and had got as far as spring tryouts with a majorleague team.
He was twenty-four years old.
“e radio tone ended,” Tibbets says tersely, “the bomb dropped, Ferebee
unclutched his sight.” e arming wires pulled out to start Little Boy’s clocks.
e first combat atomic bomb fell away from the plane, then nosed down.
It
was inscribed with autographs and messages, some of them obscene.
“Greetings to the Emperor from the men of the Indianapolis,” one
challenged.
Four tons lighter, the B-29 jumped.
Tibbets dove away:
I threw off the automatic pilot and hauled Enola Gay into the turn.
I pulled antiglare goggles over my eyes.
I couldn’t see through them; I was blind.
I threw them
to the floor.
A bright light filled the plane.
e first shock wave hit us.
We were eleven and a half miles slant range from the atomic explosion, but the whole airplane
cracked and crinkled from the blast.
I yelled “Flak!” thinking a heavy gun battery had found us.
e tail gunner had seen the first wave coming, a visible shimmer in the atmosphere, but he
didn’t know what it was until it hit.
When the second wave came, he called out a warning.
We turned back to look at Hiroshima.
e city was hidden by that awful cloud...
boiling up,
mushrooming, terrible and incredibly tall.
No one spoke for a moment; then everyone was talking.
I remember Lewis pounding my
shoulder, saying, “Look at that!
Look at that!
Look at that!” Tom Ferebee wondered about whether
radioactivity would make us all sterile.
Lewis said he could taste atomic fission.
He said it tasted
like lead.
“Fellows,” Tibbets announced on the interphone, “you have just dropped the
first atomic bomb in history.
”2589
Van Kirk remembers the two shock waves—one direct, one reflected from
the ground—vividly:
[It was] very much as if you’ve ever sat on an ash can and had somebody hit it with a baseball
bat....
e plane bounced, it jumped and there was a noise like a piece of sheet metal snapping.
ose of us who had flown quite a bit over Europe thought that it was anti-aircra fire that had exploded very close to the plane.
2590
e apparent proximity of the explosion would be one of its trademarks,
much as its heat had seemed intimate to Philip Morrison and his colleagues
at Trinity.
Turning, diving, circling back to watch, the crew of the Enola Gay missed
the early fireball; when they looked again Hiroshima smothered under a
pall.
Lewis in a postwar interview:
I don’t believe anyone ever expected to look at a sight quite like that.
Where we had seen a clear
city two minutes before, we could now no longer see the city.
We could see smoke and fires
creeping up the sides of the mountains.
2591
Van Kirk:
If you want to describe it as something you are familiar with, a pot of boiling black oil....
I thought: ank God the war is over and I don’t have to get shot at any more.
I can go home.
2592
It was a sentiment hundreds of thousands of American soldiers and sailors
would soon express, and it was hard-earned.
Leaving the scene the tail gunner, Robert Caron, had a long view:
I kept shooting pictures and trying to get the mess down over the city.
All the while I was
describing this on the intercom....
e mushroom itself was a spectacular sight, a bubbling mass
of purple-gray smoke and you could see it had a red core in it and everything was burning
inside.2593 As we got farther away, we could see the base of the mushroom and below we could see what looked like a few-hundred-foot layer of debris and smoke and what have you.
I was trying to describe the mushroom, this turbulent mass.
I saw fires springing up in different
places, like flames shooting up on a bed of coals.
I was asked to count them.
I said, “Count them?”
Hell, I gave up when there were about fieen, they were coming too fast to count.
I can still see it—
that mushroom and that turbulent mass—it looked like lava or molasses covering the whole city,
and it seemed to flow outward up into the foothills where the little valleys would come into the
plain, with fires starting up all over, so pretty soon it was hard to see anything because of the smoke.
Jacob Beser, the electronic countermeasures officer, an engineering
student at Johns Hopkins before he enlisted, found an image from the
seashore for the turmoil he saw:
at city was burning for all she was worth.
It looked like...
well, did you ever go to the beach and
stir up the sand in shallow water and see it all billow up?
at’s what it looked like to me.
2594
Little Boy exploded at 8:16:02 Hiroshima time, 43 seconds aer it le the
Enola Gay, 1,900 feet above the courtyard of Shima Hospital, 550 feet
southeast of omas Ferebee’s aiming point, Aioi Bridge, with a yield
equivalent to 12,500 tons of TNT.2595
“It was all impersonal,” Paul Tibbets would come to say.2596 It was not
impersonal for Robert Lewis.
“If I live a hundred years,” he wrote in his
journal, “I’ll never quite get these few minutes out of my mind.” 2597 Nor
would the people of Hiroshima.
2598
* * *
In my mind’s eye, like a waking dream, I could still see the tongues of fire at work on the bodies
of men.
Masuji Ibuse, Black Rain
e settlement on the delta islands of the ta River in southwestern Honshu
was named Ashihara, “reed field,” or Gokaura, “five villages,” before the
feudal lord Terumoto Mōri built a fortress there between 1589 and 1591 to
secure an outlet for his family holdings on the Inland Sea.
Mōri called his
fortress Hiro-shima-jō, “broad-island castle,” and gradually the town of
merchants and artisans that grew up around it acquired its name.
It was an
800-foot rectangle of massive stone walls protected within a wide
rectangular moat, one corner graced by a high white pagoda-like tower with
five progressively inset roofs.
e Mōri family soon lost its holdings to the
stronger Fukushima family, which lost them in turn to the Asano family in
1619.
e Asanos had the good sense to have allied themselves closely with
the Tokugawa Shogunate and ruled Hiroshima fief within that alliance for
the next two and a half centuries.
2599 Across those centuries the town
prospered.
e Asanos saw to its progressive enlargement by filling in the
estuarial shallows to connect its islands.
Divided then into long, narrow
districts by the ta’s seven distributaries, Hiroshima assumed the form of an
open, extended hand.
e restoration of the Meiji emperor in 1868 and the abolition of the
feudal clan system transformed Hiroshima fief into Hiroshima Prefecture
and the town, like the country, began vigorously to modernize.
A physician
was appointed its first mayor in 1889 when it officially became a city; the
population that celebrated the change numbered 83,387.
Five years of
expensive landfill and construction culminated that year in the opening of
Ujina harbor, a reclamation project that established Hiroshima as a major
commercial port.
Railroads came through at the turn of the century.
By then Hiroshima and its castle had found further service as an army
base and the Imperial Army Fih Division was quartered in barracks within
and around the castle grounds.
e Fih Division was the first to be shipped
to battle when Japan and China initiated hostilities in 1894; Ujina harbor
served as a major point of embarkation and would continue in that role for
the next fiy years.
e Meiji emperor moved his headquarters to the castle
in Hiroshima in September, the better to direct the war, and the Diet met in
extraordinary session in a provisional Diet building there.
Until the
following April, when the limited mainland war ended with a Japanese
victory that included the acquisition of Formosa and the southern part of
Manchuria, Hiroshima was de facto the capital of Japan.
en the emperor
returned to Tokyo and the city consolidated its gains.
It acquired further military and industrial investments in the first three
decades of the twentieth century as Japan turned to increasing international
adventure.
By the Second World War, an American study noted in the
autumn of 1945, “Hiroshima was a city of considerable military importance.
It contained the 2nd Army headquarters, which commanded the defense of
all of southern Japan.
e city was a communication center, a storage point,
and an assembly area for troops.
To quote a Japanese report, ‘Probably more
than a thousand times since the beginning of the war did the Hiroshima
citizens see off with cries of “Banzai” the troops leaving from the
harbor.’ ” 2600 From Hiroshima in 1945 the Japanese Army general staff
prepared to direct the defense of Kyushu against the impending American
invasion.
Earlier in the war the city’s population had approached 400,000, but the
threat of strategic bombing, so ominously delayed, had led the authorities to
order a series of evacuations; on August 6 the resident population numbered
some 280,000 to 290,000 civilians plus about 43,000 soldiers.
Given that
proportion of civilian to military—more than six to one—Hiroshima was
not, as Truman had promised in his Potsdam diary, a “purely military”
target.
It was not without responsibility, however, in serving the ends of war.
“e hour was early, the morning still, warm, and beautiful,” a Hiroshima
physician, Michihiko Hachiya, the director of the Hiroshima
Communications Hospital, begins a diary of the events Little Boy entrained
on August 6.
“Shimmering leaves, reflecting sunlight from a cloudless sky,
made a pleasant contrast with shadows in my garden.
”2601 e temperature
at eight o’clock was 80 degrees, the humidity 80 percent, the wind calm.
e
seven branches of the ta flowed past crowds of citizens walking and
bicycling to work.
e streetcars that clanged outside Fukuya department
store two blocks north of Aioi Bridge were packed.
ousands of soldiers,
bare to the waist, exercised at morning calesthenics on the east and west
parade grounds that flanked Hiroshima Castle a long block west of the T-
shaped bridge.
More than eight thousand schoolgirls, ordered to duty the
day before, worked outdoors in the central city helping to raze houses to
clear firebreaks against the possibility of an incendiary attack.
An air raid
alert at 7:09—the 509th weather plane—had been called off at 7:31 when the
B-29 le the area.
ree more B-sans approaching just before 8:15 sent
hardly anyone to cover, though many raised their eyes to the high silver
instruments to watch.
“Just as I looked up at the sky,” remembers a girl who was five years old at
the time and safely at home in the suburbs, “there was a flash of white light
and the green in the plants looked in that light like the color of dry
leaves.
”2602
Closer was more brutal illumination.
A young woman helping to clear
firebreaks, a junior-college student at the time, recalls: “Shortly aer the
voice of our teacher, saying ‘Oh, there’s a B!’ made us look up at the sky, we
felt a tremendous flash of lightning.
In an instant we were blinded and
everything was just a frenzy of delirium.” 2603
Closer still, in the heart of the city, no one survived to report the coming
of the light; the constrained witness of investigative groups must serve
instead for testimony.
A Yale Medical School pathologist working with a
joint American-Japanese study commission a few months aer the war,
Averill A.
Liebow, observes:
Accompanying the flash of light was an instantaneous flash of heat...
Its duration was probably
less than one tenth of a second and its intensity was sufficient to cause nearby flammable
objects...
to burst into flame and to char poles as far as 4,000 yards away from the hypocenter
[i.e., the point on the ground directly below the fireball]....
At 600–700 yards it was sufficient to
chip and roughen granite....
e heat also produced bubbling of tile to about 1,300 yards.
It has
been found by experiment that to produce this effect a temperature of [3,000° F] acting for four
seconds is necessary, but under these conditions the effect is deeper, which indicates that the temperature was higher and the duration less during the Hiroshima explosion.2604
“Because the heat in [the] flash comes in such a short time,” adds a
Manhattan Project study, “there is no time for any cooling to take place, and
the temperature of a person’s skin can be raised [120° F]...
in the first
millisecond at a distance of [2.3 miles].
”2605
e most authoritative study of the Hiroshima bombing, begun in 1976 in
consultation with thirty-four Japanese scientists and physicians, reviews the
consequences of this infernal insolation, which at half a mile from the
hypocenter was more than three thousand times as energetic as the sunlight
that had shimmered on Dr.
Hachiya’s leaves:
e temperature at the site of the explosion...
reached [5,400° F]...
and primary atomic bomb
thermal injury...
was found in those exposed within [2 miles] of the hypocenter....
Primary
burns are injuries of a special nature and not ordinarily experienced in everyday life.2606
is Japanese study distinguishes five grades of primary thermal burns
ranging from grade one, red burn, through grade three, white burn, to grade
five, carbonized skin with charring.
It finds that “severe thermal burns of
over grade 5 occurred within [0.6 to 1 mile] of the hypocenter...
and those
of grades 1 to 4 [occurred as far as 2 to 2.5 miles] from the hypocenter....
Extremely intense thermal energy leads not only to carbonization but also to
evaporation of the viscerae.
”2607 People exposed within half a mile of the
Little Boy fireball, that is, were seared to bundles of smoking black char in a
fraction of a second as their internal organs boiled away.
“Doctor,” a patient
commented to Michihiko Hachiya a few days later, “a human being who has
been roasted becomes quite small, doesn’t he?” e small black bundles now
stuck to the streets and bridges and sidewalks of Hiroshima numbered in the
thousands.2608
At the same instant birds ignited in midair.
Mosquitoes and flies, squirrels,
family pets crackled and were gone.
e fireball flashed an enormous
photograph of the city at the instant of its immolation fixed on the mineral,
vegetable and animal surfaces of the city itself.
A spiral ladder le its shadow
in unburned paint on the surface of a steel storage tank.
Leaves shielded
reverse silhouettes on charred telephone poles.
e black-brushed
calligraphy burned out of a rice-paper name card posted on a school
building door; the dark flowers burned out of a schoolgirl’s light blouse.
A
human being le the memorial of his outline in unspalled granite on the
steps of a bank.
Another, pulling a handcart, protected a handcart- and
human-shaped surface of asphalt from boiling.
Farther away, in the suburbs,
the flash induced dark, sunburn-like pigmentation sharply shadowed deep
in human skin, streaking the shape of an exposed nose or ear or hand raised
in gesture onto the faces and bodies of startled citizens: the mask of
Hiroshima, Liebow and his colleagues came to call that pigmentation.
ey
found it persisting unfaded five months aer the event.
e world of the dead is a different place from the world of the living and
it is hardly possible to visit there.
at day in Hiroshima the two worlds
nearly converged.
“e inundation with death of the area closest to the
hypocenter,” writes the American psychiatrist Robert Jay Lion, who
interviewed survivors at length, “was such that if a man survived within a
thousand meters (.6 miles) and was out of doors...
more than nine tenths
of the people around him were fatalities.” 2609 Only the living, however
inundated, can describe the dead; but where death claimed nine out of ten
or, closer to the hypocenter, ten out of ten, a living voice describing
necessarily distorts.
Survivors are like us; but the dead are radically changed,
without voice or civil rights or recourse.
Along with their lives they have
been deprived of participation in the human world.
“ere was a fearful
silence which made one feel that all people and all trees and vegetation were
dead,” remembers Yōko ta, a Hiroshima writer who survived.
2610 e
silence was the only sound the dead could make.
In what follows among the
living, remember them.
ey were nearer the center of the event; they died
because they were members of a different polity and their killing did not
therefore count officially as murder; their experience most accurately
models the worst case of our common future.
ey numbered in the
majority in Hiroshima that day.
Still only light, not yet blast: Hachiya:
I asked Dr.
Koyama what his findings had been in patients with eye injuries.
2611
“ose who watched the plane had their eye grounds burned,” he replied.
“e flash of light
apparently went through the pupils and le them with a blind area in the central portion of their
visual fields.
“Most of the eye-ground burns are third degree, so cure is impossible.”
And a German Jesuit priest reporting on one of his brothers in Christ:
Father Kopp...
was standing in front of the nunnery ready to go home.
All of a sudden he became aware of the light, felt that wave of heat, and a large blister formed on his hand.
2612
A white burn with the formation of a bleb is a grade-four burn.
Now light and blast together; they seemed simultaneous to those close in.
A junior-college girl:
Ah, that instant!
I felt as though I had been struck on the back with something like a big hammer,
and thrown into boiling oil....
I seem to have been blown a good way to the north, and I felt as
though the directions were all changed around.
2613
e first junior-college girl, the one whose teacher called everyone to look
up:
e vicinity was in pitch darkness; from the depths of the gloom, bright red flames rise crackling,
and spread moment by moment.
e faces of my friends who just before were working
energetically are now burned and blistered, their clothes torn to rags; to what shall I liken their
trembling appearance as they stagger about?
Our teacher is holding her students close to her like a
mother hen protecting her chicks, and like baby chicks paralyzed with terror, the students were
thrusting their heads under her arms.
2614
e light did not burn those who were protected inside buildings, but the
blast found them out:
at boy had been in a room at the edge of the river, looking out at the river when the explosion
came, and in that instant as the house fell apart he was blown from the end room across the road
on the river embankment and landed on the street below it.
2615 In that distance he passed through a couple of windows inside the house and his body was stuck full of all the glass it could hold.
at
is why he was completely covered with blood like that.
e blast wave, rocketing several hundred yards from the hypocenter at 2
miles per second and then slowing to the speed of sound, 1,100 feet per
second, threw up a vast cloud of smoke and dust.
“My body seemed all
black,” a Hiroshima physicist told Lion, “everything seemed dark, dark all
over....2616 en I thought, ‘e world is ending.’ ” Yōko ōta, the writer, felt
the same chill:
I just could not understand why our surroundings had changed so greatly in one instant....
I
thought it might have been something which had nothing to do with the war, the collapse of the
earth which it was said would take place at the end of the world.
2617
“Within the city,” notes Hachiya, who was severely injured, “the sky
looked as though it had been painted with light sumi [i.e., calligraphy ink],
and the people had seen only a sharp, blinding flash of light; while outside
the city, the sky was a beautiful, golden yellow and there had been a
deafening roar of sound.” 2618 ose who experienced the explosion within
the city named it pika, flash, and those who experienced it farther away
named it pika-don, flash-boom.
e houses fell as if they had been scythed.
A fourth-grade boy:
When I opened my eyes aer being blown at least eight yards, it was as dark as though I had come
up against a black-painted fence.
Aer that, as if thin paper was being peeled off one piece at a
time, it gradually began to grow brighter.
e first thing that my eyes lighted upon then was the flat
stretch of land with only dust clouds rising from it.
Everything had crumbled away in that one
moment, and changed into streets of rubble, street aer street of ruins.
2619
Hachiya and his wife ran from their house just before it collapsed and
terror opened out into horror:
e shortest path to the street lay through the house next door so through the house we went—
running, stumbling, falling, and then running again until in headlong flight we tripped over
something and fell sprawling into the street.
Getting to my feet, I discovered that I had tripped
over a man’s head.2620
“Excuse me!
Excuse me, please!” I cried hysterically.
A grocer escaped into the street:
e appearance of people was...
well, they all had skin blackened by burns....
ey had no hair
because their hair was burned, and at a glance you couldn’t tell whether you were looking at them
from in front or in back....2621 ey held their arms [in front of them]...
and their skin—not only on their hands, but on their faces and bodies too—hung down....
If there had been only one
or two such people...
perhaps I would not have had such a strong impression.
But wherever I
walked I met these people....
Many of them died along the road—I can still picture them in my
mind—like walking ghosts....
ey didn’t look like people of this world....
ey had a very
special way of walking—very slowly....
I myself was one of them.
e peeled skin that hung from the faces and bodies of these severely
injured survivors was skin that the thermal flash had instantly blistered and
the blast wave had torn loose.
A young woman:
I heard a girl’s voice clearly from behind a tree.
“Help me, please.” Her back was completely burned
and the skin peeled off and was hanging down from her hips....2622
e rescue party...
brought [my mother] home.
Her face was larger than usual, her lips were
badly swollen, and her eyes remained closed.
e skin of both her hands was hanging loose as if it
were rubber gloves.
e upper part of her body was badly burned.
A junior-college girl:
On both sides of the road, bedding and pieces of cloth had been carried out and on these were
lying people who had been burned to a reddish-black color and whose entire bodies were
frightfully swollen.
Making their way among them are three high school girls who looked as
though they were from our school; their faces and everything were completely burned and they
held their arms out in front of their chests like kangaroos with only their hands pointed
downward; from their whole bodies something like thin paper is dangling—it is their peeled-off
skin which hangs there, and trailing behind them the unburned remnants of their puttees, they
stagger exactly like sleepwalkers.
2623
A young sociologist:
Everything I saw made a deep impression—a park nearby covered with dead bodies waiting to be
cremated...
very badly injured people evacuated in my direction....
e most impressive thing I
saw was some girls, very young girls, not only with their clothes torn off but with their skin peeled
off as well....
My immediate thought was that this was like the hell I had always read about.
2624
A five-year-old boy:
at day aer we escaped and came to Hijiyama Bridge, there were lots of naked people who were
so badly burned that the skin of their whole body was hanging from them like rags.2625
A fourth-grade girl:
e people passing along the street are covered with blood and trailing the rags of their torn
clothes aer them.
2626 e skin of their arms is peeled off and dangling from their finger tips, and they go walking silently, hanging their arms before them.
A five-year-old girl:
People came fleeing from the nearby streets.
One aer another they were almost unrecognizable.
e skin was burned off some of them and was hanging from their hands and from their chins;
their faces were red and so swollen that you could hardly tell where their eyes and mouths were.
From the houses smoke black enough to scorch the heavens was covering the sky.
It was a horrible
sight.
2627
A fih-grade boy compiling a list:
e flames which blaze up here and there from the collapsed houses as though to illuminate the
darkness.
e child making a suffering, groaning sound, his burned face swollen up balloon-like
and jerking as he wanders among the fires.
e old man, the skin of his face and body peeling off
like a potato skin, mumbling prayers while he flees with faltering steps.
Another man pressing with
both hands the wound from which blood is steadily dripping, rushing around as though he has
gone mad and calling the names of his wife and child—ah—my hair seems to stand on end just to
remember.
is is the way war really looks.2628
But skin peeled by a flash of light and a gust of air was only a novelty
among the miseries of that day, something unusual the survivors could
remember to remember.
e common lot was random, indiscriminate and
universal violence inflicting terrible pain, the physics of hydraulics and
leverage and heat run riot.
A junior-college girl:
Screaming children who have lost sight of their mothers; voices of mothers searching for their little
ones; people who can no longer bear the heat, cooling their bodies in cisterns; every one among
the fleeing people is dyed red with blood.
2629
e thermal flash and the blast started fires and very quickly the fires
became a firestorm from which those who could ambulate ran away and
those who sustained fractures or were pinned under houses could not; two
months later Liebow’s group found the incidence of fractures among
Hiroshima survivors to be less than 4.5 percent.
“It was not that injuries
were few,” the American physicians note; “rather, almost none who had lost
the capacity to move escaped the flames.” 2630 A five-year-old girl:
e whole city...
was burning.
Black smoke was billowing up and we could hear the sound of big
things exploding....
ose dreadful streets.
e fires were burning.
ere was a strange smell all
over.
Blue-green balls of fire were driing around.
I had a terrible lonely feeling that everybody else
in the world was dead and only we were still alive.
2631
Another girl the same age:
I really have to shudder when I think of that atom bomb which licked away the city of Hiroshima
in one or two minutes on the 6th of August, 1945....2632
We were running for our lives.
On the way we saw a soldier floating in the river with his
stomach all swollen.
In desperation he must have jumped into the river to escape from the sea of
fire.
A little farther on dead people were lined up in a long row.
Al little farther on there was a
woman lying with a big log fallen across her legs so that she couldn’t get away.
When Father saw that he shouted, “Please come and help!”
But not a single person came to help.
ey were all too intent on saving themselves.
Finally Father lost his patience, and shouting, “Are you people Japanese or not?” he took a rusty
saw and cut off her leg and rescued her.
A little farther on we saw a man who had been burned black as he was walking.
A first-grade girl whose mother was pinned under the wreckage of their
house:
I was determined not to escape without my mother.
2633 But the flames were steadily spreading and my clothes were already on fire and I couldn’t stand it any longer.
So screaming, “Mommy,
Mommy!” I ran wildly into the middle of the flames.
No matter how far I went it was a sea of fire
all around and there was no way to escape.
So beside myself I jumped into our [civil defense] water tank.
e sparks were falling everywhere so I put a piece of tin over my head to keep out the fire.
e water in the tank was hot like a bath.
Beside me there were four or five other people who were
all calling someone’s name.
While I was in the water tank everything became like a dream and
sometime or other I became unconscious....
Five days aer that [I learned that] Mother had
finally died just as I had le her.
Similarly a woman who was thirteen at the time who was still haunted by
guilt when Lion interviewed her two decades later:
I le my mother there and went off....
I was later told by a neighbor that my mother had been
found dead, face down in a water tank...
very close to the spot where I le her....
2634 If I had been a little older or stronger I could have rescued her....
Even now I still hear my mother’s voice
calling me to help her.
“Beneath the wreckage of the houses along the way,” recounts the Jesuit
priest, “many have been trapped and they scream to be rescued from the
oncoming flames.” 2635
“I was completely amazed,” a third-grade boy remembers of the
destruction:2636
While I had been thinking it was only my house that had fallen down, I found that every house in
the neighborhood was either completely or half-collapsed.
e sky was like twilight.
Pieces of
paper and cloth were caught on the electric wires....
On that street crowds were fleeing toward the
west.
Among them were many people whose hair was burned, whose clothes were torn and who
had burns and injuries....
Along the way the road was full to overflowing with victims, some with
great wounds, some burned, and some who had lost the strength to move farther....
While we
were going along the embankment, a muddy rain that was dark and chilly began to fall.
Around
the houses I noticed automobiles and footballs, and all sorts of household stuff that had been
tossed out, but there was no one who stopped to pick up a thing.
But against the background of horror the eye of the survivor persisted in
isolating the exceptional.
A thirty-five-year-old man:
A woman with her jaw missing and her tongue hanging out of her mouth was wandering around
the area of Shinsho-machi in the heavy, black rain.2637 She was heading toward the north crying for help.
A four-year-old boy:
ere were a lot of people who were burned to death and among them were some who were
burned to a cinder while they were standing up.2638
A sixth-grade boy:
Nearby, as if he were guarding these people, a policeman was standing, all covered with burns and stark naked except for some scraps of his trousers.
2639
A seventeen-year-old girl:
I walked past Hiroshima Station...
and saw people with their bowels and brains coming out....
I
saw an old lady carrying a suckling infant in her arms....
I saw many children...
with dead
mothers....
I just cannot put into words the horror I felt.2640
At Aioi Bridge:
I was walking among dead people....
It was like hell.
e sight of a living horse burning was very
striking.
2641
A schoolgirl saw “a man without feet, walking on his ankles.” 2642 A
woman remembers:
A man with his eyes sticking out about two inches called me by name and I felt sick....
People’s
bodies were tremendously swollen—you can’t imagine how big a human body can swell up.2643
A businessman whose son was killed:
In front of the First Middle School there were...
many young boys the same age as my son...
and
what moved me most to pity was that there was one dead child lying there and another who
seemed to be crawling over him in order to run away, both of them burned to blackness.2644
A thirty-year-old woman:
e corpse lying on its back on the road had been killed immediately....
Its hand was lied to the
sky and the fingers were burning with blue flames.
2645 e fingers were shortened to one-third and distorted.
A dark liquid was running to the ground along the hand.
A third-grade girl:
ere was also a person who had a big splinter of wood stuck in his eye—I suppose maybe he
couldn’t see—and he was running around blindly.2646
A nineteen-year-old Ujina girl:
I saw for the first time a pile of burned bodies in a water tank by the entrance to the broadcasting
station.2647 en I was suddenly frightened by a terrible sight on the street 40 to 50 meters from Shukkeien Garden.
ere was a charred body of a woman standing frozen in a running posture
with one leg lied and her baby tightly clutched in her arms.
Who on earth could she be?
A first-grade girl:
A streetcar was all burned and just the skeleton of it was le, and inside it all the passengers were burned to a cinder.
When I saw that I shuddered all over and started to tremble.
2648
“e more you hear the sadder the stories get,” writes a girl who was five
years old at Hiroshima.
2649 “Since just in my family there is so much sadness
from it,” deduces a boy who was also five, “I wonder how much sadness
other people must also be having.
”2650
Eyes watched as well from the other side.
A history professor Lion
interviewed:
I went to look for my family.
Somehow I became a pitiless person, because if I had pity, I would not
have been able to walk through the city, to walk over those dead bodies.
e most impressive thing
was the expression in people’s eyes—bodies badly injured which had turned black—their eyes
looking for someone to come and help them.2651 ey looked at me and knew that I was stronger than they....
I saw disappointment in their eyes.
ey looked at me with great expectation, staring
right through me.
It was very hard to be stared at by those eyes.
Massive pain and suffering and horror everywhere the survivors turned
was their common lot.
A fih-grade boy:
I and Mother crawled out from under the house.
ere we found a world such as I had never seen
before, a world I’d never even heard of before.
I saw human bodies in such a state that you couldn’t
tell whether they were humans or what....
ere is already a pile of bodies in the road and people
are writhing in death agonies.2652
A junior-college girl:
At the base of the bridge, inside a big cistern that had been dug out there, was a mother weeping
and holding above her head a naked baby that was burned bright red all over its body, and another
mother was crying and sobbing as she gave her burned breast to her baby.
In the cistern the
students stood with only their heads above the water and their two hands, which they clasped as
they imploringly cried and screamed, calling their parents.
But every single person who passed was
wounded, all of them, and there was no one to turn to for help.
2653
A six-year-old boy:
Near the bridge there were a whole lot of dead people.2654 ere were some who were burned black and died, and there were others with huge burns who died with their skins bursting, and
some others who died all stuck full of broken glass.
ere were all kinds.
Sometimes there were
ones who came to us asking for a drink of water.
ey were bleeding from their faces and from
their mouths and they had glass sticking in their bodies.
And the bridge itself was burning
furiously....
e details and the scenes were just like Hell.
Two first-grade girls:
We came out to the Miyuki Bridge.
Both sides of the street were piled with burned and injured
people.
And when we looked back it was a sea of bright red flame.2655
*
e fire was spreading furiously from one place to the next and the sky was dark with
smoke....
2656
e [emergency aid station] was jammed with people who had terrible wounds, some whose
whole body was one big burn....
e flames were spreading in all directions and finally the whole
city was one sea of fire and sparks came flying over our heads.
A fih-grade boy:
I had the feeling that all the human beings on the face of the earth had been killed off, and only the
five of us [i.e., his family] were le behind in an uncanny world of the dead....
I saw several people plunging their heads into a half-broken water tank and drinking the water....
When I was
close enough to see inside the tank I said “Oh!” out loud and instinctively drew back.
What I had
seen in the tank were the faces of monsters reflected from the water dyed red with blood.
2657 ey had clung to the side of the tank and plunged their heads in to drink and there in that position
they had died.
From their burned and tattered middy blouses I could tell that they were high
school girls, but there was not a hair le on their heads; the broken skin of their burned faces was
stained bright red with blood.
I could hardly believe that these were human faces.
A physician sharing his horror with Hachiya:
Between the [heavily damaged] Red Cross Hospital and the center of the city I saw nothing that
wasn’t burned to a crisp.
Streetcars were standing at Kawaya-cho and Kamiya-cho and inside were
dozens of bodies, blackened beyond recognition.
I saw fire reservoirs filled to the brim with dead
people who looked as though they had been boiled alive.
In one reservoir I saw a man, horribly
burned, crouching beside another man who was dead.
He was drinking blood-stained water out of
the reservoir....2658 In one reservoir there were so many dead people there wasn’t enough room for them to fall over.
ey must have died sitting in the water.
A husband helping his wife escape the city:
While taking my severely-wounded wife out to the riverbank by the side of the hill of Nakahiro-
machi, I was horrified, indeed, at the sight of a stark naked man standing in the rain with his eyeball in his palm.
He looked to be in great pain but there was nothing that I could do for him.
2659
e naked man may have been the same victim one of Hachiya’s later
visitors remembered noticing, or he may have been another:
ere were so many burned [at a first-aid station] that the odor was like drying squid.
ey looked
like boiled octopuses....
I saw a man whose eye had been torn out by an injury, and there he stood
with his eye resting in the palm of his hand.
What made my blood run cold was that it looked like the eye was staring at me.2660
e people ran to the rivers to escape the firestorm; in the testimony of
the survivors there is an entire subliterature of the rivers.
A third-grade boy:
Men whose whole bodies were covered with blood, and women whose skin hung from them like a
kimono, plunged shrieking into the river.
All these become corpses and their bodies are carried by
the current toward the sea.2661
A first-grade girl:
We were still in the river by evening and it got cold.
No matter where you looked there was
nothing but burned people all around.
2662
A sixth-grade girl:
Bloated corpses were driing in those seven formerly beautiful rivers; smashing cruelly into bits
the childish pleasure of the little girl, the peculiar odor of burning human flesh rose everywhere in
the Delta City, which had changed to a waste of scorched earth.2663
A young ship designer whose response to the bombing was to rush home
immediately to Nagasaki:
I had to cross the river to reach the station.2664 As I came to the river and went down the bank to the water, I found that the stream was filled with dead bodies.
I started to cross by crawling over
the corpses, on my hands and knees.
As I got about a third of the way across, a dead body began to
sink under my weight and I went into the water, wetting my burned skin.
It pained severely.
I could
go no further, as there was a break in the bridge of corpses, so I turned back to the shore.
A third-grade boy:
I got terribly thirsty so I went to the river to drink.
From upstream a great many black and burned
corpses came floating down the river.
I pushed them away and drank the water.
At the margin of
the river there were corpses lying all over the place.2665
A fih-grade boy:
e river became not a stream of flowing water but rather a stream of driing dead bodies.
No
matter how much I might exaggerate the stories of the burned people who died shrieking and of
how the city of Hiroshima was burned to the ground, the facts would still be clearly more
terrible.2666
Terrible was what a Hachiya patient found beyond the river:
ere was a man, stone dead, sitting on his bicycle as it leaned against a bridge railing....
You could tell that many had gone down to the river to get a drink of water and had died where they
lay.
2667 I saw a few live people still in the water, knocking against the dead as they floated down the river.
ere must have been hundreds and thousands who fled to the river to escape the fire and
then drowned.
2668
e sight of the soldiers, though, was more dreadful than the dead people floating down the
river.
I came onto I don’t know how many, burned from the hips up; and where the skin had
peeled, their flesh was wet and mushy....
And they had no faces!
eir eyes, noses and mouths had been burned away, and it looked like
their ears had melted off.
It was hard to tell front from back.
e suffering in the crowded private park of the Asano family was
doubled when survivors faced death a second time, another Hachiya
confidant saw:
Hundreds of people sought refuge in the Asano Sentei Park.
ey had refuge from the approaching
flames for a little while, but gradually, the fire forced them nearer and nearer the river, until at length everyone was crowded onto the steep bank overlooking the river....
Even though the river is more than one hundred meters wide along the border of the park, balls
of fire were being carried through the air from the opposite shore and soon the pine trees in the
park were afire.
e poor people faced a fiery death if they stayed in the park and a watery grave if
they jumped in the river.
I could hear shouting and crying, and in a few minutes they began to fall
like toppling dominoes into the river.
Hundreds upon hundreds jumped or were pushed in the
river at this deep, treacherous point and most were drowned.
“Along the streetcar line circling the western border of the park,” adds
Hachiya, “they found so many dead and wounded they could hardly
walk.” 2669
e setting of the sun brought no relief.
A fourteen-year-old boy:
Night came and I could hear many voices crying and groaning with pain and begging for
water.
2670 Someone cried, “Damn it!
War tortures so many people who are innocent!” Another said, “I hurt!
Give me water!” is person was so burned that we couldn’t tell if it was a man or a
woman.
e sky was red with flames.
It was burning as if scorching heaven.
A fih-grade girl:
Everybody in the shelter was crying out loud.
2671 ose voices....
ey aren’t cries, they are moans that penetrate to the marrow of your bones and make your hair stand on end....
I do not know how many times I called begging that they would cut off my burned arms and
legs.
A six-year-old boy:
If you think of Brother’s body divided into le and right halves, he was burned on the right side,
and on the inside of the le side....2672
at night Brother’s body swelled up terribly badly.
He looked just like a bronze Buddha....
[At Danbara High School field hospital] every classroom...
was full of dreadfully burned
people who were lying about or getting up restlessly.
ey were all painted with mercurochrome
and white salve and they looked like red devils and they were waving their arms around like ghosts
and groaning and shrieking.
Soldiers were dressing their burns.
e next morning, remembers a boy who was five years old at the time,
“Hiroshima was all a wasted land.
”2673 e Jesuit, coming in from a suburb
to aid his brothers, testifies to the extent of the destruction:
e bright day now reveals the frightful picture which last night’s darkness had partly concealed.
Where the city stood, everything as far as the eye could reach is a waste of ashes and ruin.
Only
several skeletons of buildings completely burned out in the interior remain.
e banks of the rivers
are covered with dead and wounded, and the rising waters have here and there covered some of the
corpses.2674 On the broad street in the Hakushima district, naked, burned cadavers are particularly numerous.
Among them are the wounded who are still alive.
A few have crawled under the
burned-out autos and trams.
Frightfully injured forms beckon to us and then collapse.
Hachiya corroborates the priest’s report:
e streets were deserted except for the dead.
Some looked as if they had been frozen by death
while still in the full action of flight; others lay sprawled as though some giant had flung them to
their death from a great height....
2675
Nothing remained except a few buildings of reinforced concrete....
For acres and acres the city
was like a desert except for scattered piles of brick and roof tile.
I had to revise my meaning of the
word destruction or choose some other word to describe what I saw.
Devastation may be a better
word, but really, I know of no word or words to describe the view.2676
e history professor Lion interviewed is similarly at a loss:
I climbed Hikiyama Hill and looked down.
I saw that Hiroshima had disappeared....
I was
shocked by the sight....
What I felt then and still feel now I just can’t explain with words.
Of
course I saw many dreadful scenes aer that—but that experience, looking down and finding
nothing le of Hiroshima—was so shocking that I simply can’t express what I felt....
Hiroshima
didn’t exist—that was mainly what I saw—Hiroshima just didn’t exist.2677
Without familiar landmarks, the streets filled with rubble, many had
difficulty finding their way.
For Yōko ta the city’s history itself had been
demolished:
I reached a bridge and saw that the Hiroshima Castle had been completely leveled to the ground,
and my heart shook like a great wave....
2678 e city of Hiroshima, entirely on flat land, was made three-dimensional by the existence of the white castle, and because of this it could retain a classical
flavor.
Hiroshima had a history of its own.
And when I thought about these things, the grief of stepping over the corpses of history pressed upon my heart.
Of 76,000 buildings in Hiroshima 70,000 were damaged or destroyed,
48,000 totally.
“It is no exaggeration to say,” reports the Japanese study, “that
the whole city was ruined instantaneously.” 2679 Material losses alone equaled
the annual incomes of more than 1.1 million people.
“In Hiroshima many
major facilities—prefectural office, city hall, fire departments, police
stations, national railroad stations, post offices, telegram and telephone
offices, broadcasting station, and schools—were totally demolished or
burned.
Streetcars, roads, and electricity, gas, water, and sewage facilities
were ruined beyond use.
Eighteen emergency hospitals and thirty-two first-
aid clinics were destroyed.” 2680 Ninety percent of all medical personnel in
the city were killed or disabled.
Not many of the survivors worried about buildings; they had all they
could do to deal with their injuries and find and cremate their dead, an
obligation of particular importance to the Japanese.
A man remembers
seeing a woman bloody in torn wartime mompei pantaloons, naked above
the waist, her child strapped to her back, carrying a soldier’s helmet:
[She was] in search of a place to cremate her dead child.
e burned face of the child on her back
was infested with maggots.
I guess she was thinking of putting her child’s bones in a battle helmet
she had picked up.
I feared she would have to go far to find burnable material to cremate her child.
2681
A young woman who had been in charge of a firebreak group and who
was badly burned on one shoulder recalls the mass cremations:
We gathered the dead bodies and made big mountains of the dead and put oil on them and burned
them.
And people who were unconscious woke up in the piles of the dead when they found
themselves burning and came running out.2682
Another Hachiya visitor:
Aer a couple of days, there were so many bodies stacked up no one knew who was who, and
decomposition was so extensive the smell was unbearable.
During those days, wherever you went,
there were so many dead lying around it was impossible to walk without encountering them—
swollen, discolored bodies with froth oozing from their noses and mouths.
2683
A first-grade girl:
On the morning of the 9th, what the soldiers on the clearance team lied out of the ruins was the
very much changed shape of Father.
e Civil Defense post [where he worked] was at Yasuda near
Kyobashi, in front of the tall chimney that was demolished last year.
He must have died there at the
foot of it; his head was already just a white skull....
Mother and my little sister and I, without
thinking, clutched that dead body and wailed.
Aer that Mother went with it to the crematory at
Matsukawa where she found corpses piled up like a mountain.
2684
Having moved his hospital sickbed to a second-floor room with blown-
out windows that fire had sterilized, Hachiya himself could view and smell
the ruins:
Towards evening, a light southerly wind blowing across the city waed to us an odor suggestive of
burning sardines....
Towards Nigitsu was an especially large fire where the dead were being
burned by the hundreds....
ese glowing ruins and the blazing funeral pyres set me to
wondering if Pompeii had not looked like this during its last days.
But I think there were not so
many dead in Pompeii as there were in Hiroshima.2685
ose who did not die seemed for a time to improve.
But then, explains
Lion, they sickened:
Survivors began to notice in themselves and others a strange form of illness.
It consisted of nausea,
vomiting, and loss of appetite; diarrhea with large amounts of blood in the stools; fever and
weakness; purple spots on various parts of the body from bleeding into the skin...
inflammation
and ulceration of the mouth, throat and gums...
bleeding from the mouth, gums, throat, rectum,
and urinary tract...
loss of hair from the scalp and other parts of the body...
extremely low white
blood cell counts when those were taken...
and in many cases a progressive course until
death.
2686
Only gradually did the few surviving and overworked Japanese doctors
realize that they were seeing radiation sickness; “atomic bomb illness,”
explains the authoritative Japanese study, “is the first and only example of
heavy lethal and momentary doses of whole body irradiation” in the history
of medicine.2687 A few human beings had been accidentally overexposed to
X rays and laboratory animals had been exposed and sacrificed for study but
no large population had ever experienced so extensive and deadly an assault
of ionizing radiation before.
e radiation brought further suffering, Hachiya reports in his diary:
Following the pika, we thought that by giving treatment to those who were burned or injured recovery would follow.
2688 But now it was obvious that this was not true.
People who appeared to be recovering developed other symptoms that caused them to die.
So many patients died without
our understanding the cause of death that we were all in despair....
Hundreds of patients died during the first few days; then the death rate declined.
Now, it was
increasing again....
As time passed, anorexia [i.e., loss of appetite] and diarrhea proved to be the
most persistent symptoms in patients who failed to recover.
Direct gamma radiation from the bomb had damaged tissue throughout
the bodies of the exposed.
2689 e destruction required cell division to
manifest itself, but radiation temporarily suppresses cell division; hence the
delayed onset of symptoms.
e blood-forming tissues were damaged worst,
particularly those that produce the white blood cells that fight infection.
Large doses of radiation also stimulate the production of an anticlotting
factor.
2690 e outcome of these assaults was massive tissue death, massive
hemorrhage and massive infection.
“Hemorrhage was the cause of death in
all our cases,” writes Hachiya, but he also notes that the pathologist at his
hospital “found changes in every organ of the body in the cases he...
autopsied.
”2691, 2692 Liebow reports “evidence of generalization of infection
with masses of bacteria in...
organs as remote from the surface [of the
body] as the brain, bone marrow and eye.” 2693 e operator of a
crematorium in the Hiroshima suburbs, a connoisseur of mortality, told
Lion “the bodies were black in color...
most of them had a peculiar smell,
and everyone thought this was from the bomb....
e smell when they
burned was caused by the fact that these bodies were decayed, many of them
even before being cremated—some of them having their internal organs
decay even while the person was living.” 2694 Yōko ta raged:
We were being killed against our will by something completely unknown to us....
It is the misery
of being thrown into a world of new terror and fear, a world more unknown than that of people
sick with cancer.
2695
In the depths of his loss a boy who was a fourth-grader at Hiroshima
found words for the unspeakable:
Mother was completely bedridden.
e hair of her head had almost all fallen out, her chest was
festering, and from the two-inch hole in her back a lot of maggots were crawling in and out.
e
place was full of flies and mosquitoes and fleas, and an awfully bad smell hung over everything.
Everywhere I looked there were many people like this who couldn’t move.
From the evening when
we arrived Mother’s condition got worse and we seemed to see her weakening before our eyes.
Because all night long she was having trouble breathing, we did everything we could to relieve her.
e next morning Grandmother and I fixed some gruel.
As we took it to Mother, she breathed her
last breath.
When we thought she had stopped breathing altogether, she took one deep breath and
did not breathe any more aer that.
is was nine o’clock in the morning of the 19th of August.
At
the site of the Japan Red Cross Hospital, the smell of the bodies being cremated is overpowering.
Too much sorrow makes me like a stranger to myself, and yet despite my grief I cannot cry.2696
Not human beings alone died at Hiroshima.
Something else was destroyed
as well, the Japanese study explains—that shared life Hannah Arendt calls
the common world:
In the case of an atomic bombing...
a community does not merely receive an impact; the
community itself is destroyed.
2697 Within 2 kilometers of the atomic bomb’s hypocenter all life and property were shattered, burned, and buried under ashes.
e visible forms of the city where
people once carried on their daily lives vanished without a trace.
e destruction was sudden and
thorough; there was virtually no chance to escape....
Citizens who had lost no family members in
the holocaust were as rare as stars at sunrise....
e atomic bomb had blasted and burned hospitals, schools, city offices, police stations, and
every other kind of human organization....
Family, relatives, neighbors, and friends relied on a
broad range of interdependent organizations for everything from birth, marriage, and funerals to
firefighting, productive work, and daily living.
ese traditional communities were completely
demolished in an instant.
Destroyed, that is, were not only men, women and thousands of children
but also restaurants and inns, laundries, theater groups, sports clubs, sewing
clubs, boys’ clubs, girls’ clubs, love affairs, trees and gardens, grass, gates,
gravestones, temples and shrines, family heirlooms, radios, classmates,
books, courts of law, clothes, pets, groceries and markets, telephones,
personal letters, automobiles, bicycles, horses—120 war-horses—musical
instruments, medicines and medical equipment, life savings, eyeglasses, city
records, sidewalks, family scrapbooks, monuments, engagements, marriages,
employees, clocks and watches, public transportation, street signs, parents,
works of art.
“e whole of society,” concludes the Japanese study, “was laid
waste to its very foundations.
”2698 Lion’s history professor saw not even
foundations le.
“Such a weapon,” he told the American psychiatrist, “has
the power to make everything into nothing.” 2699
ere remains the question of how many died.
e U.S.
Army Medical
Corps officer who proposed the joint American-Japanese study to Douglas
MacArthur thought as late as August 28 that “the total number of casualties
reported at Hiroshima is approximately 160,000 of which 8,000 are
dead.” 2700 e Jesuit priest’s contemporary reckoning approaches the
appalling reality and illuminates further the destruction of the common
world:
How many people were a sacrifice to this bomb?
ose who had lived through the catastrophe
placed the number of dead at at least 100,000.
Hiroshima had a population of 400,000.
Official
statistics place the number who had died at 70,000 up to September 1st, not counting the missing
—and 130,000 wounded, among them 43,500 severely wounded.
Estimates made by ourselves on
the basis of groups known to us show that the number of 100,000 dead is not too high.
Near us
there are two barracks, in each of which forty Korean workers lived.
On the day of the explosion
they were laboring on the streets of Hiroshima.2701 Four returned alive to one barracks and sixteen to the other.
Six hundred students of the Protestant girls’ school worked in a factory, from which
only thirty or forty returned.
Most of the peasant families in the neighborhood lost one or more of
their members who had worked at factories in the city.
Our next door neighbor, Tamura, lost two
children and himself suffered a large wound since, as it happened, he had been in the city on that
day.
e family of our reader suffered two dead, father and son; thus a family of five members
suffered at least two losses, counting only the dead and severely wounded.
ere died the mayor,
the president of the central Japan district, the commander of the city, a Korean prince who had
been stationed in Hiroshima in the capacity of an officer, and many other high-ranking officers.
Of
the professors of the University thirty-two were killed or severely wounded.
Especially hard-hit
were the soldiers.
e Pioneer Regiment was almost entirely wiped out.
e barracks were near the
center of the explosion.
More recent estimates place the number of deaths up to the end of 1945 at
140,000.
e dying continued; five-year deaths related to the bombing
reached 200,000.
e death rate for deaths up to the end of 1945 was 54
percent, an extraordinary density of killing; by contrast, the death rate for
the March 9 firebombing of Tokyo, 100,000 deaths among 1 million
casualties, was only 10 percent.
Back at the U.S.
Army Institute of Pathology
in Washington in early 1946 Liebow used a British invention, the
Standardized Casualty Rate, to compute that Little Boy produced casualties,
including dead, 6,500 times more efficiently than an ordinary HE bomb.
2702
“ose scientists who invented the...
atomic bomb,” writes a young woman
who was a fourth-grade student at Hiroshima—“what did they think would
happen if they dropped it?
”2703
Harry Truman learned of the atomic bombing of Hiroshima at lunch on
board the Augusta en route home from Potsdam.
“is is the greatest thing
in history,” he told a group of sailors dining at his table.
“It’s time for us to
get home.
”2704
Groves called Oppenheimer from Washington on August 6 at two in the
aernoon to pass along the news:
Gen.
G:
I’m very proud of you and all of your people.
Dr.
O:
It went all right?
Gen.
G:
Apparently it went with a tremendous bang.
Dr.
O:
When was this, was it aer sundown?
Gen.
G:
No, unfortunately, it had to be in the daytime on account of security of the plane
and that was le in the hands of the Commanding General over there....
Dr.
O:
Right.
Everybody is feeling reasonably good about it and I extend my heartiest
congratulations.
It’s been a long road.
Gen.
G:
Yes, it has been a long road and I think one of the wisest things I ever did was when
I selected the director of Los Alamos.
Dr.
O:
Well, I have my doubts, General Groves.
Gen.
G:
Well, you know I’ve never concurred with those doubts at any time.2705
If Oppenheimer, who knew nothing yet of the extent of the destruction,
was only feeling “reasonably good” about his handiwork, Leo Szilard felt
terrible when the story broke.
e press release issued from the White
House that day called the atomic bomb “the greatest achievement of
organized science in history” and threatened the Japanese with “a rain of
ruin from the air, the like of which has never been seen on this earth.” 2706 In Chicago on Quadrangle Club stationery Szilard scribbled a hasty letter to
Gertrud Weiss:
I suppose you have seen today’s newspapers.
Using atomic bombs against Japan is one of the
greatest blunders of history.
Both from a practical point of view on a 10-year scale and from the
point of view of our moral position.
I went out of my way and very much so in order to prevent it
but as today’s papers show without success.
It is very difficult to see what wise course of action is
possible from here on.2707
Otto Hahn, interned with the German atomic scientists on a rural estate
in England, was shattered:
At first I refused to believe that this could be true, but in the end I had to face the fact that it was
officially confirmed by the President of the United States.
I was shocked and depressed beyond
measure.
e thought of the unspeakable misery of countless innocent women and children was
something that I could scarcely bear.
2708
Aer I had been given some gin to quiet my nerves, my fellow-prisoners were also told the
news....
By the end of a long evening of discussion, attempts at explanation, and self-reproaches I
was so agitated that Max von Laue and the others became seriously concerned on my behalf.
ey
ceased worrying only at two o’clock in the morning, when they saw that I was asleep.
But if some were disturbed by the news, others were elated, Otto Frisch
found at Los Alamos:
en one day, some three weeks aer [Trinity], there was a sudden noise in the laboratory, of
running footsteps and yelling voices.
2709 Somebody opened my door and shouted, “Hiroshima has been destroyed!”; about a hundred thousand people were thought to have been killed.
I still
remember the feeling of unease, indeed nausea, when I saw how many of my friends were rushing
to the telephone to book tables at the La Fonda Hotel in Santa Fe, in order to celebrate.
Of course
they were exalted by the success of their work, but it seemed rather ghoulish to celebrate the
sudden death of a hundred thousand people, even if they were “enemies.”
e American writer Paul Fussell, an Army veteran, emphasizes “the
importance of experience, sheer vulgar experience, in influencing one’s
views about the first use of the bomb.
”2710 e experience Fussell means is
“that of having come to grips, face to face, with an enemy who designs your
death”:
I was a 21-year-old second lieutenant leading a rifle platoon.
Although still officially in one piece,
in the German war I had been wounded in the leg and back severely enough to be adjudged, aer
the war, 40 percent disabled.
But even if my leg buckled whenever I jumped out of the back of the
truck, my condition was held to be satisfactory for whatever lay ahead.
When the bombs dropped
and news began to circulate that [the invasion of Japan] would not, aer all, take place, that we
would not be obliged to run up the beaches near Tokyo assault-firing while being mortared and
shelled, for all the fake manliness of our facades we cried with relief and joy.
We were going to live.
We were going to grow up to adulthood aer all.
In Japan the impasse persisted between civilian and military leaders.
To
the civilians the atomic bomb looked like a golden opportunity to surrender
without shame, but the admirals and the generals still despised
unconditional surrender and refused to concur.
Foreign Minister Togo
continued to pursue Soviet mediation as late as August 8.
Ambassador Sato
asked for a meeting with Molotov that day; Molotov set the meeting for
eight in the evening, then moved it up to five o’clock.
Despite earlier notice
of the power of the new weapon, news of the devastation of a Japanese city
by an American atomic bomb had surprised and shocked Stalin and
prompted him to accelerate his war plans; Molotov announced that
aernoon to the Japanese ambassador that the Soviet Union would consider
itself at war with Japan as of the next day, August 9.
Well-armed Soviet
troops, 1.6 million strong, waited in readiness on the Manchurian border
and attacked the ragged Japanese an hour aer midnight.
In the meantime a progaganda effort that originated in the U.S.
War
Department was developing in the Marianas.2711 Hap Arnold cabled Spaatz
and Farrell on August 7 ordering a crash program to impress the facts of
atomic warfare on the Japanese people.
e impetus probably came from
George Marshall, who was surprised and shocked that the Japanese had not
immediately sued for peace.
“What we did not take into account,” he said
long aerward, “...
was that the destruction would be so complete that it
would be an appreciable time before the actual facts of the case would get to
Tokyo.
2712 e destruction of Hiroshima was so complete that there was no
communication at least for a day, I think, and maybe longer.”
e Navy and the Air Force both lent staff and facilities, including Radio
Saipan and a printing press previously used to publish a Japaneselanguage
newspaper distributed weekly over the Empire by B-29s.
e working group
that assembled on August 7 in the Marianas decided to attempt to distribute
6 million leaflets to forty-seven Japanese cities with populations exceeding
100,000.
Writing the leaflet occupied the group through the night.
A
historical memorandum prepared for Groves in 1946 notes that the working
group discovered in a midnight conference with Air Force commanders “a
certain reluctance to fly single B-29’s over the Empire, reluctance arising
from the fact that enemy opposition to single flights was expected to be
increased as the result of the total damage to Hiroshima by one airplane.
”2713
e proposed text of the leaflet was ready by morning and was flown from
Saipan to Tinian at dawn for Farrell’s approval.
Groves’ deputy edited it and
ordered the revised text called to Radio Saipan by inter-island telephone for
broadcast to the Japanese every fieen minutes; radio transmission probably
began the same day.
e text described the atomic bomb as “the equivalent
in explosive power to what 2,000 of our giant B-29’s can carry on a single
mission,” suggested skeptics “make inquiry as to what happened to
Hiroshima” and asked the Japanese people to “petition the Emperor to end
the war.” Otherwise, it threatened, “we shall resolutely employ this bomb
and all our other superior weapons.
”2714 Printing millions of copies of a
leaflet took time, and distribution was delayed some hours further by a local
shortage of T-3 leaflet bombs.
Such was the general confusion that Nagasaki
did not receive its quota of warning leaflets until August 10.
2715
Assembly of Fat Man unit F31 was progressing at Tinian in the
airconditioned assembly building designed for that purpose.
F31 was the
second Fat Man with real high explosives that the Tinian team had
assembled; the first, with lower-quality HE castings and a non-nuclear core,
unit F33, had been ready since August 5 for a test drop but would not be
dropped until August 8 because the key 509th crews were busy delivering
Little Boy and being debriefed.
e F31 Fat Man, Norman Ramsey writes,
was originally scheduled for dropping on August 11 local time....
However, by August 7 it became
apparent that the schedule could be advanced to August 10.
2716 When Parsons and Ramsey proposed this change to Tibbets, he expressed regret that the schedule could not be advanced two
days instead of only one since good weather was forecast for August 9 and the five succeeding days
were expected to be bad.
It was finally agreed that [we] would try to be ready for August 9
provided all concerned understood that the advancement of the date by two full days introduced a
large measure of uncertainty into the probability of meeting such a drastically revised schedule.
One member of the Fat Man assembly team, a young Navy ensign named
Bernard J.
O’Keefe, remembers the mood of urgency in the Marianas, where
the war was still a daily threat:
With the success of the Hiroshima weapon, the pressure to be ready with the much more complex
implosion device became excruciating.
2717 We sliced off another day, scheduling it for August 10.
Everyone felt that the sooner we could get off another mission, the more likely it was that the
Japanese would feel that we had large quantities of the devices and would surrender sooner.
We were certain that one day saved would mean that the war would be over one day sooner.
Living on
that island, with planes going out every night and people dying not only in B-29s shot down, but in
naval engagements all over the Pacific, we knew the importance of one day; the Indianapolis
sinking also had a strong effect on us.
Despite that urgency, O’Keefe adds, August 9 sat less well; “the scientific
staff, dog-tired, met and warned Parsons that cutting two full days would
prevent us from completing a number of important checkout procedures,
but orders were orders.”
e young Providence, Rhode Island, native had been a student at George
Washington University in 1939 and had attended the conference there on
January 25 at which Niels Bohr announced the discovery of fission.
Now on
Tinian more than six years later, on the night of August 7, it became
O’Keefe’s task to check out Fat Man for the last time before its working parts
were encased beyond easy access in armor.
In particular, he was required to
connect the firing unit mounted on the front of the implosion sphere with
the four radar units mounted in the tail by plugging in a cable inaccessibly
threaded around the sphere inside its dural casing:
When I returned at midnight, the others in my group le to get some sleep; I was alone in the
assembly room with a single Army technician to make the final connection....2718
I did my final checkout and reached for the cable to plug it into the firing unit.
It wouldn’t fit!
“I must be doing something wrong,” I thought.
“Go slowly; you’re tired and not thinking
straight.”
I looked again.
To my horror, there was a female plug on the firing set and a female plug on the
cable.
I walked around the weapon and looked at the radars and the other end of the cable.
Two
male plugs....
I checked and double-checked.
I had the technician check; he verified my findings.
I felt a chill and started to sweat in the air-conditioned room.
What had happened was obvious.
In the rush to take advantage of good weather, someone had
gotten careless and put the cable in backward.
Removing the cable and reversing it would mean partly disassembling the
implosion sphere.
It had taken most of a day to assemble it.
ey would miss
the window of good weather and slip into the five days of bad weather that
had worried Paul Tibbets.
e second atomic bomb might be delayed as
long as a week.
e war would go on, O’Keefe thought.
He decided to
improvise.
Although “nothing that could generate heat was ever allowed in
an explosive assembly room,” he determined to “unsolder the connectors
from the two ends of the cable, reverse them, and resolder them”:2719
My mind was made up.
I was going to change the plugs without talking to anyone, rules or no
rules.
I called in the technician.
ere were no electrical outlets in the assembly room.
We went out
to the electronics lab and found two long extension cords and a soldering iron.
We...
propped the
door open so it wouldn’t pinch the extension cords (another safety violation).
I carefully removed
the backs of the connectors and unsoldered the wires.
I resoldered the plugs onto the other ends of
the cable, keeping as much distance between the soldering iron and the detonators as I could as I
walked around the weapon....
We must have checked the cable continuity five times before
plugging the connectors into the radars and the firing set and tightening up the joints.
I was
finished.2720
So, the next day, was Fat Man, the two armored steel ellipsoids of its
ballistic casing bolted together through bathtub fittings to lugs cast into the
equatorial segments of the implosion sphere, its boxed tail sprouting radar
antennae just as Little Boy’s had done.
By 2200 on August 8 it had been
loaded into the forward bomb bay of a B-29 named Bock’s Car aer its usual
commander, Frederick Bock, but piloted on this occasion by Major Charles
W.
Sweeney.
Sweeney’s primary target was Kokura Arsenal on the north
coast of Kyushu; his secondary was the old Portuguese- and
Dutchinfluenced port city of Nagasaki, the San Francisco of Japan, home of
that country’s largest colony of Christians, where the Mitsubishi torpedoes
used at Pearl Harbor had been made.
Bock’s Car flew off Tinian at 0347 on August 9.
2721 e Fat Man
weaponeer, Navy Commander Frederick L.
Ashworth, remembers the flight
to rendezvous:
e night of our takeoff was one of tropical rain squalls, and flashes of lightning stabbed into the
darkness with disconcerting regularity.
e weather forecast told us of storms all the way from the
Marianas to the Empire.
2722 Our rendezvous was to be off the southeast coast of Kyushu, some fieen hundred miles away.
ere we were to join with our two companion observation B-29s that
took off a few minutes behind us.
Fat Man was fully armed at takeoff except for its green plugs, which
Ashworth changed to red only ten minutes into the mission so that Sweeney
could cruise above the squalls at 17,000 feet, St.
Elmo’s fire glowing on the
propellers of his plane.
2723 e pilot soon discovered he would enjoy no
reserve of fuel; the fuel selector that would allow him to feed his engines
from a 600-gallon tank of gasoline in his a bomb bay refused to work.
He
circled over Yakoshima between 0800 and 0850 Japanese time waiting for his
escorts, one of which never did catch up.
e finger plane at Kokura
reported three-tenths low clouds, no intermediate or high clouds and
improving conditions, but when Bock’s Car arrived there at 1044 heavy
ground haze and smoke obscured the target.
“Two additional runs were
made,” Ashworth notes in his flight log, “hoping that the target might be
picked up aer closer observation.2724 However, at no time was the aiming
point seen.”
Jacob Beser controlled electronic countermeasures on the Fat Man
mission as he had done on the Little Boy mission before.
He remembers of
Kokura that “the Japs started to get curious and began sending fighters up
aer us.
We had some flak bursts and things were getting a little hairy, so
Ashworth and Sweeney decided to make a run down to Nagasaki, as there
was no sense dragging the bomb home or dropping it in the ocean.” 2725
Sweeney had enough fuel le for only one pass over the target before
nursing his aircra to an emergency landing on Okinawa.
When he
approached Nagasaki he found the city covered with cloud; with his fuel low
he could either bomb by radar or jettison a bomb worth several hundred
million dollars into the sea.
It was Ashworth’s call and rather than waste the
bomb he authorized a radar approach.
At the last minute a hole opened in
the cloud cover long enough to give the bombardier a twenty-second visual
run on a stadium several miles upriver from the original aiming point
nearer the bay.
Fat Man dropped from the B-29, fell through the hole and
exploded 1,650 feet above the steep slopes of the city at 11:02 A.M., August 9,
1945, with a force later estimated at 22 kilotons.
e steep hills confined the
larger explosion; it caused less damage and less loss of life than Little Boy.
But 70,000 died in Nagasaki by the end of 1945 and 140,000 altogether
across the next five years, a death rate like Hiroshima’s of 54 percent.
e
survivors spoke with equal eloquence of unspeakable suffering.
A U.S.
Navy
officer visited the city in mid-September and described its condition then,
more than a month aer the bombing, in a letter home to his wife:
A smell of death and corruption pervades the place, ranging from the ordinary carrion smell to somewhat subtler stenches with strong overtones of ammonia (decomposing nitrogenous matter, I
suppose).2726 e general impression, which transcends those derived from the evidence of our physical senses, is one of deadness, the absolute essence of death in the sense of finality without
hope of resurrection.
And all this is not localized.
It’s everywhere, and nothing has escaped its touch.
In most ruined cities you can bury the dead, clean up the rubble, rebuild the houses and
have a living city again.
One feels that is not so here.
Like the ancient Sodom and Gomorrah, its
site has been sown with salt and ichabod1 is written over its gates.
e military leaders of Japan had still not agreed to surrender.
2727 e
Emperor Hirohito therefore took the extraordinary step of forcing the issue.
e resulting surrender offer, delivered through Switzerland, reached
Washington on Friday morning, August 10.
It acknowledged acceptance of
the Potsdam Declaration except in one crucial regard: that it “does not
comprise any demand which prejudices the prerogatives of His Majesty as a
Sovereign Ruler.” 2728
Truman met immediately with his advisers, including Stimson and
Byrnes.
Stimson thought the President would accept the Japanese offer;
doing so, he wrote in his diary, would be “taking a good plain horse sense
position that the question of the Emperor was a minor matter compared
with delaying a victory in the war which was now in our hands.” 2729 Jimmy
Byrnes persuasively disagreed.
“I cannot understand,” he argued, “why we
should go further than we were willing to go at Potsdam when we had no
atomic bomb, and Russia was not in the war.
”2730 He was thinking as usual
of domestic politics; accepting Japan’s condition, he warned, might mean the
“crucifixion of the President.” 2731 Secretary of the Navy James Forrestal
proposed a compromise: the President should communicate to the Japanese
his “willingness to accept [their offer], yet define the terms of surrender in
such a manner that the intents and purposes of the Potsdam Declaration
would be clearly accomplished.” 2732
Truman bought the compromise but Byrnes draed the reply.
It was
deliberately ambiguous in its key provisions:
From the moment of surrender the authority of the Emperor and the Japanese Government to rule
the state shall be subject to the Supreme Commander of the Allied Powers....
e Emperor and the Japanese High Command will be required to sign the surrender terms....
e ultimate form of government shall, in accordance with the Potsdam Declaration, be
established by the freely expressed will of the Japanese people.
Nor did Byrnes hurry the message along; he kept it in hand overnight and
only released it for broadcast by radio and delivery through Switzerland the
following morning.
Stimson, still trying to bring his Air Force under control, had argued at
the Friday morning meeting that the United States should suspend
bombing, including atomic bombing.
Truman thought otherwise, but when
he met with the cabinet that aernoon he had partly reconsidered.
“We
would keep up the war at its present intensity,” Forrestal paraphrases the
President, “until the Japanese agreed to these terms, with the limitation
however that there will be no further dropping of the atomic bomb.
”2733, 2734
Henry Wallace, the former Vice President who was now Secretary of
Commerce, recorded in his diary the reason for the President’s change of
mind:
Truman said he had given orders to stop the atomic bombing.
He said the thought of wiping out
another 100,000 people was too horrible.
He didn’t like the idea of killing, as he said, “all those
kids.
”2735
e restriction came none too soon.
Groves had reported to Marshall that
morning that he had gained four days in manufacture and expected to ship a
second Fat Man plutonium core and initiator from New Mexico to Tinian
on August 12 or 13.
“Provided there are no unforeseen difficulties in
manufacture, in transportation to the theatre or aer arrival in the theatre,”
he concluded cautiously, “the bomb should be ready for delivery on the first
suitable weather aer 17 or 18 August.” 2736 Marshall told Groves the
President wanted no further atomic bombing except by his express order
and Groves decided to hold up shipment, a decision in which Marshall
concurred.
e Japanese government learned of Byrnes’ reply to its offer of
conditional surrender not long aer midnight on Sunday, August 12, but
civilian and military leaders continued to struggle in deadlocked debate.
Hirohito resisted efforts to persuade him to reverse his earlier commitment
to surrender and called a council of the imperial family to collect pledges of
support from the princes of the blood.
e Japanese people were not yet told
of the Byrnes reply but knew of the peace negotiations and waited in
suspense.
e young writer Yukio Mishima found the suspense surreal:
It was our last chance.
People were saying that Tokyo would be [atomicbombed] next.
Wearing
white shirts and shorts, I walked about the streets.
e people had reached the limits of
desperation and were now going about their affairs with cheerful faces.2737 From one moment to the next, nothing happened.
Everywhere there was an air of cheerful excitement.
It was just as
though one was continuing to blow up an already bulging toy balloon, wondering: “Will it burst
now?
Will it burst now?”
Strategic Air Forces commander Carl Spaatz cabled Lauris Norstad on
August 10 proposing “placing [the] third atomic bomb...
on Tokyo,” where
he thought it would have a salutary “psychological effect on government
officials.
”2738 On the other hand, continuing area incendiary bombing
disturbed him; “I have never favored the destruction of cities as such with all
inhabitants being killed,” he confided to his diary on August 11.
He had sent
off 114 B-29’s on August 10; because of bad weather and misgivings he
canceled a mission scheduled for August 11 and restricted operations
thereaer to “attacks on military targets visually or under very favorable
blind bombing conditions.” American weather planes over Tokyo were no
longer drawing anti-aircra fire; Spaatz thought that fact “unusual.” 2739
e vice chief of the Japanese Navy’s general staff, the man who had
conceived and promoted the kamikaze attacks of the past year that had
added to American bewilderment and embitterment at Japanese ways,
crashed a meeting of government leaders on the evening of August 13 with
tears in his eyes to offer “a plan for certain victory”: “sacrifice 20,000,000
Japanese lives in a special [kamikaze] attack.
”2740 Whether he meant the 20
million to attack the assembled might of the Allies with rocks or bamboo
spears the record does not reveal.
A B-29 leaflet barrage forced the issue the next morning.
Leaflet bombs
showered what remained of Tokyo’s streets with a translation of Byrnes’
reply.
e Lord Keeper of the Privy Seal knew such public revelation would
harden the military against surrender.
He carried the leaflet immediately to
the Emperor and just before eleven that morning, August 14, Hirohito
assembled his ministers and counselors in the imperial air raid shelter.
He
told them he found the Allied reply “evidence of the peaceful and friendly
intentions of the enemy” and considered it “acceptable.
”2741 He did not
specifically mention the atomic bomb; even that terrific leviathan
submerged in the general misery:
I cannot endure the thought of letting my people suffer any longer.
A continuation of the war would bring death to tens, perhaps even hundreds, of thousands of persons.
e whole nation
would be reduced to ashes.
How then could I carry on the wishes of my imperial ancestors?
He asked his ministers to prepare an imperial rescript—a formal edict—that
he might broadcast personally to the nation.
e officials were not legally
bound to do so—the Emperor’s authority lay outside the legal structure of
the government—but by older and deeper bonds than law they were bound,
and they set to work.
In the meantime Washington had grown impatient.
Groves was asked on
August 13 about “the availability of your patients together with the time
estimate that they could be moved and placed.” 2742 Stimson recommended
proceeding to ship the nuclear materials for the third bomb to Tinian.
Marshall and Groves decided to wait another day or two.
Truman ordered
Arnold to resume area incendiary attacks.
Arnold still hoped to prove that
his Air Force could win the war; he called for an all-out attack with every
available B-29 and any other bombers in the Pacific theater and mustered
more than a thousand aircra.
Twelve million pounds of high-explosive and
incendiary bombs destroyed half of Kumagaya and a sixth of Isezaki, killing
several thousand more Japanese, even as word of the Japanese surrender
passed through Switzerland to Washington.
e first hint of surrender reached American bases in the Pacific by radio
in the form of a news bulletin from the Japanese news agency Dōmei at 2:49
P.M.
on August 14—1:49 A.M.
in Washington:
Flash!
Flash!
Tokyo, Aug.
14—It is learned an imperial message accepting the Potsdam
Proclamation is forthcoming soon.
2743
e bombers droned on even aer that, but eventually that day the bombs
stopped falling.
Truman announced the Japanese acceptance in the
aernoon.
ere were last-minute acts of military rebellion in Tokyo—a
high officer assassinated, an unsuccessful attempt to steal the phonograph
recording of the imperial rescript, a brief takeover of a division of Imperial
Guards, wild plans for a coup.
But loyalty prevailed.
e Emperor broadcast
to a weeping nation on August 15; his 100 million subjects had never heard
the high, antique Voice of the Crane before:
Despite the best that has been done by everyone...
the war situation has developed not necessarily
to Japan’s advantage, while the general trends of the world have all turned against her interest.2744
Moreover, the enemy has begun to employ a new and most cruel bomb, the power of which to do
damage is indeed incalculable, taking the toll of many innocent lives....
is is the reason why We
have ordered the acceptance of the provisions of the Joint declaration of the Powers....
e hardships and sufferings to which Our nation is to be subjected hereaer will be certainly
great.
We are keenly aware of the inmost feelings of all ye, Our subjects.
However, it is according to
the dictate of time and fate that We have resolved to pave the way for a grand peace for all generations to come by enduring the unendurable and suffering what is insufferable....
Let the entire nation continue as one family from generation to generation.
“If it had gone on any longer,” writes Yukio Mishima, “there would have
been nothing to do but go mad.” 2745
“An atomic bomb,” the Japanese study of Hiroshima and Nagasaki
emphasizes, “...
is a weapon of mass slaughter.” 2746 A nuclear weapon is in
fact a total-death machine, compact and efficient, as a simple graph prepared
from Hiroshima statistics demonstrates:
e percentage of people killed depends simply on distance from the
hypocenter; the relation between death percentage and distance is inversely
proportional and the killing, as Gil Elliot emphasizes, is no longer selective:
By the time we reach the atom bomb, Hiroshima and Nagasaki, the ease of access to target and the
instant nature of macro-impact mean that both the choice of city and the identity of the victim has
become completely randomized, and human technology has reached the final platform of self-
destructiveness.2747 e great cities of the dead, in numbers, remain Verdun, Leningrad and Auschwitz.
But at Hiroshima and Nagasaki the “city of the dead” is finally transformed from a
metaphor into a literal reality.
e city of the dead of the future is our city and its victims are—not
French and German soldiers, nor Russian citizens, nor Jews—but all of us without reference to
specific identity.
“e experience of these two cities,” the Japanese study emphasizes, “was the
opening chapter to the possible annihilation of mankind.
”2748
On August 24, having recently heard about the man holding an eyeball,
Dr.
Michihiko Hachiya suffered a nightmare.
Like the myth of the Sphinx—
destruction to those who cannot answer its riddle, whom ignorance or
inattention or arrogance misleads—the dream of this Japanese doctor who
was wounded in the world’s first atomic bombing and who ministered to
hundreds of victims must be counted one of the millennial visions of
mankind:
e night had been close with many mosquitoes.
Consequently, I slept poorly and had a frightful
dream.
2749
It seems I was in Tokyo aer the great earthquake and around me were decomposing bodies
heaped in piles, all of whom were looking right at me.
I saw an eye sitting on the palm of a girl’s
hand.
Suddenly it turned and leaped into the sky and then came flying back towards me, so that,
looking up, I could see a great bare eyeball, bigger than life, hovering over my head, staring point
blank at me.
I was powerless to move.
“I awakened short of breath and with my heart pounding,” Michihiko
Hachiya remembers.
So do we all.
Acknowledgments
ese men and women who participated in the events of this book
generously made time for interviews and correspondence: Philip Abelson,
Luis W.
Alvarez, David L.
Anderson, William A.
Arnold, Hans Bethe, Rose
Bethe, Eugene T.
Booth, Sakae Itoh, Shigetoshi Iwamatsu, George
Kistiakowsky, Willis E.
Lamb, Jr., Leon Love, Alfred O.
C.
Nier, I.
I.
Rabi,
Stefan Rozental, Glenn Seaborg, Emilio Segrè, Edward Teller, Stanislaw
Ulam, Eugene Wigner and Herbert York.
Michael Korda took the chance of sponsorship.
David Halberstam,
Geoffrey Ward and Edward O.
Wilson vouched for me to the Ford
Foundation.
Arthur L.
Singer, Jr., saved the day.
e Cockefair Chair in
Continuing Education at the University of Missouri-Kansas City and its
director, Michael Mardikes, lent support.
Louis Brown offered physics
coaching and wise counsel far beyond the call of any duty and is not
responsible for lapses in either regard.
Egon Weiss went out of his way to
arrange access to the Szilard Papers.
e Linda Hall Library of Science and
its former director, Larry X.
Besant, and the UMKC Library and its former
director, Kenneth LaBudde, never failed.
I visited or corresponded with a number of institutions; their staffs guided
me with competence and courtesy: American Institute of Physics Niels Bohr
Library; Argonne National Laboratory; Bibliothek und Archiv für
Geschichte der Max-Planck-Gesellscha, Dahlem; Columbia University;
Department of Terrestrial Magnetism, Carnegie Institution of Washington;
Hiroshima Peace Culture Foundation; J.
Robert Oppenheimer Memorial
Committee; Lawrence Berkeley Laboratory; Library of Congress; Los
Alamos National Laboratory; National Archives; Niels Bohr Institute,
Copenhagen; e Readers Digest of Japan; United States Air Force Museum,
Wright-Patterson AFB; United States Military Academy Library; University
of California—San Diego; University of Chicago Library.
Friends and colleagues helped with research, advice, encouragement, aid:
Millicent Abell, Hans and Elisabeth Archenhold, John Aubrey, Dan Baca,
Roy and Sandra Beatty, David Butler, Margaret Conyngham, Gil Elliot, Jon
Else, Susie Evans, Peter Francis, Kimball Higgs, Jack Holl, Ulla Holm, Joan
and Frank Hood, Jim and Reiko Ishikawa, Sigurd Johansson, Tadao Kaizuka,
Edda and Rainer Konig, Barbro Lucas, omas Lyons, Karen McCarthy,
Donald and Britta McNemar, Yasuo Miyazaki, Hiroyuki Nakagawa, Kimiko
Nakai, Rolf Neuhaus, Issei Nishimori, Fredrik Nordenham, Patricia
O’Connell, Gena Peyton, Edward Quattlebaum, P.
Wayne Reagan, Edward
Reese, Katherine Rhodes, Timothy Rhodes, Bill Jack Rodgers, Siegfried
Ruschin, Robert G.
Sachs, Silva Sandow, Sabine Schaffner, Ko Shioya, R.
Jeffrey Smith, Robert Stewart, Lewis H.
Strauss, Linda Talbot, Sharon Gibbs
ibodeau, Josiah ompson, Kosta Tsipsis, Erma Valenti, Joan Warnow,
Spencer Weart, Paul Williams, Edward Wolowiec, Mike Yoshida.
Luis Alvarez and Emilio Segré were kind enough to read the galleys and
offered invaluable suggestions.
Mary saw it through.
1.
English novelist H.
G.
Wells.
His 1914 novel, The World Set Free, predicted atomic bombs,
atomic war and world government.
2.
As a young man, Hungarian physicist Leo Szilard dreamed of saving the world.
“If we could
find an element which is split by neutrons...”
3.
Pierre and Marie Curie in their Paris laboratory, c.
1900.
The elements they first isolated from
pitchblende residues, polonium and radium, radiated far more energy than any chemical process
could account for.
4.
New Zealander Ernest Rutherford discovered the atomic nucleus.
James Jeans called him “the
Newton of atomic physics.” C.
1902.
5.
The Cavendish Laboratory in Cambridge, England, the world center of early-20th-century
experimental physics.
6.
Otto Hahn and Lise Meitner, chemist and physicist, made a productive team in Berlin.
7.
Niels Bohr on the threshold of greatness, summer 1911, with his fiancée, Margrethe.
8.
October 1912: The Kaiser led the way to dedicate the new institute built on farmland he
donated in the Berlin suburb of Dahlem.
9.
The Kaiser Wilhelm Institute for Chemistry, another measure of burgeoning German power.
10.
Chemist Fritz Haber (left) and theoretician Albert Einstein, c.
1914.
Haber guided German
development of poison gases in the Great War; Einstein spoke out for pacifism and pursued the
general theory of relativity.
He had already formulated the fateful mass-energy equivalence, E =
mc2.
11.
Cambridge physicist Harry Moseley, killed at Gallipoli, 1915.
A eulogist said his death alone
made the war a “hideous” and “irreparable” crime.
12.
American soldiers preparing for gas drill, c.
1917.
“It was a way of saving countless lives,”
Otto Hahn remembers Fritz Haber arguing of poison gas, “...
if it meant that the war could be
brought to an end sooner.”
13.
Niels Bohr’s new Institute for Theoretical Physics in Copenhagen, completed in 1921.
The
best young physicists in the world pilgrimaged here to work and to learn.
14.
Niels Bohr in the 1920s.
15.
At Como, Italy, in 1927, Enrico Fermi, Werner Heisenberg and Wolfgang Pauli ( l.
to r.)
heard Bohr define complementarity.
16.
Fermi and his group in Rome prepared through the early 1930s for major work and found it
bombarding the elements with neutrons to induce artificial radioactivities previously unknown.
Uranium was a complex puzzle.
L.
to r., Emilio Segré, Enrico Persico and Enrico Fermi at Ostia,
1927.
17.
The Physics Institute on the Via Panisperna.
18.
Cambridge physicist Francis Aston’s mass-spectrograph sorted out isotopes by mass.
Their
whole-number weights led to an understanding of binding energy, the glue that holds atoms
together.
“Personally I think there is no doubt that sub-atomic energy is available all around us,”
Aston lectured, “and that one day man will release and control its almost infinite power.”
19.
The first anti-Jewish law Adolf Hitler promulgated, in April 1933, stripped “non-Aryan”
academics of their posts.
More than 100 physicists fled Germany.
20.
With Europe in turmoil, Bohr’s annual Copenhagen conferences became job forums.
In the
front row ( l.
to r.
): Oskar Klein, Bohr, Heisenberg, Pauli, George Gamow, Lev Landau, Hendrik
Kramers.
21.
Frédéric and Irène Joliot-Curie at the Radium Institute in Paris discovered artificial
radioactivity but missed the neutron.
C.
1935.
22.
Identifying the third basic constituent of matter fell to Rutherford protégé James Chadwick.
The discovery of the neutron in 1932 opened the atomic nucleus to detailed examination.
Chadwick’s colleagues hailed him as “the personification of the ideal experimentalist.”
23.
At Berkeley in the 1930s theoretician Robert Oppenheimer (left) and experimentalist Ernest
O.
Lawrence built a great American school of physics.
24.
Lawrence’s Nobel Prize-winning cyclotron battered secrets from the nucleus and proved a
potent source of neutrons.
Here Lawrence examines the vacuum chamber of the 37-inch
machine, completed in 1937.
25.
Two distinguished Cavendish directors: J.
J.
Thomson (left) and Ernest Rutherford in the
1930s.
26.
Mathematician John von Neumann departed Europe early for a lifetime appointment at the
Institute for Advanced Study.
27.
Leo Szilard, photographed by Gertrud Weiss at Oxford in 1936.
The chain-reaction patent
was already a British military secret.
28.
After England, the physicists who escaped Nazi Germany emigrated in increasing numbers
to the United States.
Future Nobel laureate Hans Bethe won appointment at Cornell.
29.
His Stuttgart professor’s daughter Rose Ewald followed in 1936.
“Rose was then twenty, and
I fell in love with her.”
30.
The war against the Jews spread to Italy and threatened Laura Fermi.
The 1938 Nobel Prize
offered the couple escape with financial security; with their children Giulio and Nella they went
on from Stockholm to New York.
“We have founded the American branch of the Fermi family,”
Fermi mocked.
31.
Lise Meitner at 59 in 1937.
At Christmastime 1938 in Stockholm she heard from Otto Hahn
of his stunning discovery with Fritz Strassmann that slow neutrons bombarding uranium made
barium—the first evidence that the uranium atom split.
32.
Otto Frisch, c.
1938.
With Meitner, his aunt, he prized out the revolutionary meaning of the
Hahn-Strassmann uranium discovery.
33.
Otto Hahn at sixty in 1939.
His “barium fantasy” would change the world.
34.
One of Hahn’s radiochemistry worktables at the Kaiser Wilhelm Institute for Chemistry.
35.
The medieval fortress at Kungälv, Sweden, that looked down upon Frisch and Meitner as
they worked.
36.
Herbert Anderson at Columbia first demonstrated nuclear fission in the United States in
January 1939.
37.
At Munich in September 1938, British Prime Minister Neville Chamberlain agreed to Nazi
demands to partition Czechoslovakia.
“Peace with honour,” he told the London crowds.
“Complete surrender,” Winston Churchill charged.
38.
The APO target room at the Carnegie Institution’s Department of Terrestrial Magnetism,
Washington, D.C., after the demonstration of fission there on the night of January 28, 1939.
L.
to r., Robert Meyer, Merle Tuve, Fermi, Richard Roberts, Léon Rosenfeld, Erik Bohr, Niels Bohr, Gregory Breit, John Fleming.
39.
Albert Einstein’s 1939 letter to President Franklin Roosevelt reporting the possibility of
German atomic bomb research led FDR to appoint a Uranium Committee headed by
ineffectual Bureau of Standards director Lyman J.
Briggs (left).
40.
The leaders of wartime American science, 1940.
L.
to r, Ernest Lawrence, Arthur Compton,
Vannevar Bush, James Bryant Conant, Karl Compton, Alfred Loomis.
41.
War came to Europe with the German invasion of Poland on September 1, 1939.
Here Polish
citizens in Warsaw study Nazi proclamations.
Roosevelt appealed to the belligerents to refrain
from bombing civilians.
42.
Genia and Rudolf Peierls.
While American efforts stalled, Peierls and Otto Frisch in England
in 1940 worked out the essential theory of a fast-fission uranium bomb fueled with U235 and
convinced his British colleagues that it was feasible.
43.
Eugene T.
Booth (left) and John Dunning (right) decided in 1940 to experiment with gaseous barrier diffusion to separate U235 from U238.
The British took the same route.
44.
Economist Alexander Sachs had carried the Einstein letter of warning to Roosevelt; he
pushed the conservative Briggs committee without success for another year.
45.
Nobel laureate theoretician Eugene P.
Wigner, the third member of the “Hungarian
conspiracy” with Szilard and Edward Teller.
Szilard called him “the conscience of the project”
from beginning to end.
46.
Alfred O.
C.
Nier separated a sample of U235 with his mass-spectrograph; Columbia used it
to confirm the rare isotope’s responsibility for slow-neutron fission.
47.
Australian Mark Oliphant visited the United States in 1941 and helped goad the American
atomic-bomb program to commitment.
48.
Glenn Seaborg, the codiscoverer of plutonium, with his bride-to-be, Helen Griggs, Los
Angeles, 1942.
49.
Strategic bombing soon bridged the barrier of the English Channel.
Here: Coventry
Cathedral, destroyed by German bombs.
50.
The Japanese surprise attack on Pearl Harbor, December 7, 1941, finally precipitated the
entry of the United States into the war against not only Japan but Germany and Italy as well.
Immediately U.S.
atomic bomb development accelerated.
51.
Franklin Roosevelt saw the longterm potential and instinctively reserved nuclear-weapons
policy to himself.
52.
Louis B.
Werner and Burris Cunningham in Chicago the day they isolated the first pure
sample of plutonium, August 20, 1942.
53.
Chicago Pile Number One, the first man-made nuclear reactor, under construction at the
University of Chicago, November 1942.
Lower layer holds uranium oxide pseudospheres,
unfinished dead layer overlying.
Note hammer in foreground for scale.
54.
Oak Ridge Alpha I calutron racetrack for electromagnetic separation of U235.
Silver-wound
magnets protrude like ribs spaced by semicircular mass- spectrometer tanks.
Spare tanks in left
foreground.
55.
K-25 gaseous-diffusion plant, Oak Ridge, Tennessee.
Built to monumental scale, the
structure is half a mile long with 42.6 acres under roof.
56.
William S.
“Deke” Parsons and Philip Abelson.
Parsons directed ordnance development at
Los Alamos; Abelson pioneered liquid thermal diffusion for uranium enrichment.
57.
Abelson’s liquid thermal diffusion rack.
Steam circulated through an inner pipe, cooling
water through an outer, causing U235 to diffuse inward and circulate upward.
The resulting
enriched material fed Ernest Lawrence’s hungry calutrons.
58.
U.S.
plutonium-production complex on the Columbia River at Hanford, Washington.
Twelve-hundred-ton graphite reactors drilled with 2,004 channels held uranium slugs; neutrons
from fission transmuted 250 parts per million of U238 to plutonium.
D pile in foreground
between water tanks.
59.
Pile face showing slug channels.
60.
“Queen Mary” plutonium separation plant, Hanford.
Dissolved irradiated slugs progressed
by remote control through separation stages down the length of this 800-foot concrete building.
61.
Interior showing processing cells.
62.
The Norsk Hydro hydrogen electrolysis plant at Vemork, Norway, produced heavy water for
German uranium research until disabled by Allied bombing.
63.
The ferry Hydro on Lake Tinnsjö, Norway, sunk by commandos while carrying the last
Norsk Hydro heavy water to Germany.
64.
A secret laboratory was established in 1943 north of Santa Fe, New Mexico, on the forested
Los Alamos mesa at 7,200 feet.
Here scientists and engineers assembled to design and build the
first atomic bombs.
The Army Corps of Engineers constructed fourplex family apartments for
housing.
65.
Experiments at Los Alamos determined the critical masses of U235 and Pu239.
Adding
U235 cubes to a subcritical assembly within blocks of beryllium tamper measurably increased
neutron flux.
66.
The Los Alamos Tech Area.
67.
The guillotine mechanism for studying supercritical assemblies (the Dragon experiment).
68.
The first RaLa test.
Note Army tanks for observers, lower left.
69.
Niels Bohr learned of the U.S.
program in 1943.
The bomb, he foresaw, would end major
war and challenge the nation-states to move toward an open world.
70.
Polish mathematician Stanislaw Ulam calculated hydrodynamics at Los Alamos; in 1951 he
conceived the essential breakthrough arrangement for a workable H-bomb.
71.
Hungarian theorist Edward Teller (left) helped make the plutonium bomb work; Navy
physicist Norris Bradbury directed its test assembly at Trinity.
Teller guided H-bomb theoretical
studies at Los Alamos.
72.
Seth Neddermeyer.
His idea of using explosives to squeeze a nuclear core to criticality saved
the plutonium bomb when impurities threatened its design.
73.
Kitty Oppenheimer at Los Alamos with Peter.
74.
The Los Alamos staff worked a six-day week; Sundays there was time for recreation.
Shown
here on a Sunday hike, L.
to r., standing, Emilio Segré, Enrico Fermi, Hans Bethe, H.
H.
Staub,
Victor Weisskopf; seated, Erika Staub, Elfriede Segré.
75.
The Normandy invasion in May 1944 led ultimately to Allied victory in Europe 12 months
later.
Supreme Commander Dwight D.
Eisenhower visited the front lines.
76.
Ferocious Japanese resistance claimed increasing U.S.
casualties in the Pacific—30,000 of the
60,000 Americans committed on Iwo Jima, where 20,000 Japanese died.
77.
At Los Alamos, Ukrainian chemist George Kistiakowsky (here riding Crisis) manufactured
and tested the explosive lenses for the Fat Man bomb.
78.
Early model Fat Man implosion bomb, upper segments removed to show interior.
Overall
diameter is about 5 feet.
79.
X-ray motion picture frames of implosion experiment.
Note compression of core in final
frames.
80.
Shot tower at Trinity Site in the desert north of Alamogordo, N.M., where Los Alamos
prepared in the spring of 1945 to test the plutonium bomb.
81.
Base Camp.
82.
After inserting the initiator into the core and mounting the assembly in a cylindrical plug of
tamper, the crew delivered it to the tower for insertion into the bomb.
83.
Firing and instrumentation bunkers.
84.
Theoretician Philip Morrison (left), here with Ernest Lawrence, escorted the plutonium
core to Trinity.
85.
Sgt.
Herbert Lehr delivered the core in its shockmounted case to the McDonald Ranch
assembly room at Trinity about 6 P.M., July 12, 1945.
Assembly proceeded the following
morning.
86.
After inserting the initiator into the core and mounting the assembly in a cylindrical plug of
tamper, the crew delivered it to the tower for insertion into the bomb.
87.
The completely assembled Trinity bomb in its tower, with Norris Bradbury attending, July
15, 1945.
88-93.
The first man-made nuclear explosion: Trinity, 0529:45 hours et seq., July 16, 1945.
The
sequence runs down this page and up the next.
Note change of scale as the fireball expands.
“This power of nature which we had first understood it to be,” said I.
I.
Rabi, “—well, there it
was.”
94.
Twenty-four hours later Trinity, seen from the air, revealed a radioactive crater of green,
glassy, fused desert sand.
(Smaller crater to the south marks the 100-ton explosive test.)
95.
Los Alamos director Robert Oppenheimer (left) subsequently visited the site with
Manhattan Project commanding general Leslie R.
Groves and found only the reinforcing rods
of the tower footings left unvaporized.
96.
In a final postwar celebration the British mission at Los Alamos pantomimed the war years.
A stepladder stood in for the Trinity shot tower.
Note Otto Frisch (third from left) in skirt
playing housemaid.
97.
Beginning in 1944, U.S.
Air Force B-29’s systematically firebombed Japanese cities.
L.
to r.,
Generals Lauris Norstad, Curtis LeMay and Thomas Power.
98.
At the Potsdam Conference in July 1945 President Harry Truman welcomed the bomb as a
substitute for Soviet entry into the Pacific war.
L.
to r., Soviet Premier Joseph Stalin, Truman,
British Prime Minister Winston Churchill.
99.
Henry L.
Stimson, Secretary of War, directed bomb development.
100.
Jimmy Byrnes, Secretary of State, advised Truman to use the bomb to force the
unconditional surrender of the Japanese.
101.
The Hiroshima bomb, Little Boy, was a cannon with a U235 bullet and three U235 target
rings fitted to its muzzle.
Tinian, August 1945.
102.
Hiroshima prestrike briefing on Tinian.
L.
to r., first row, Joseph Buscher, unknown; second
row, Norman Ramsey, Paul Tibbets; third row, Thomas Ferrell, Adm.
Parnell, Deke Parsons,
Luis Alvarez; fourth row, left of Parsons, Charles Sweeney, right of Parsons, Thomas Ferebee,
right of Alvarez, Theodore Van Kirk; Harold Agnew.
103.
Crew of the Enola Gay before Hiroshima mission: l.
to r., standing, John Porter (ground maintenance officer), Theodore Van Kirk (navigator), Thomas Ferebee (bombardier), Paul
Tibbets (pilot), Robert Lewis (copilot), Jacob Beser (radar countermeasures officer); kneeling,
Joseph Stiborik (radar operator), Robert Caron (tail gunner), Richard Nelson (radio operator),
Robert Shumard (assistant engineer), Wyatt Duzenbury (flight engineer).
Not shown: Deke
Parsons (weaponeer), Morris Jeppson (electronics test officer).
104.
The mushroom cloud over Hiroshima, August 6, 1945, photographed from the strike
mission B-29.
105.
The Enola Gay landing at Tinian after the Hiroshima strike.
106.
A panorama of Hiroshima damage.
Some roads have been cleared.
Buildings left standing
were earthquake-reinforced.
Little Boy exploded with a yield equivalent to 12,500 tons of TNT
(12.5 KT).
Modern atomic artillery shells deliver equal yield; one Minuteman III missile is
armed with the equivalent of 84 Hiroshimas.
107.
Miyuki Bridge, Hiroshima, 1.4 miles from the hypocenter, 11 A.M., August 6, 1945.
108.
The Hiroshima fireball instantly raised surface temperatures within a mile of the
hypocenter well above 1,000° F.
109.
A man pulling a cart shadowed in unburned asphalt, Hiroshima.
110.
Thermal burns on a soldier exposed within half a mile of the Hiroshima hypocenter.
His
sash protected his waist.
111.
Unidentified corpse, Hiroshima.
Deaths to the end of 1945 totaled 140,000.
112.
Staircase on a gas storage tank shadowed in uncharred paint, Hiroshima.
113.
Fat Man was ready on Tinian on August 8, 1945, and flew the following day.
Note graffiti
on tail assembly.
114.
The plutonium bomb exploded over Nagasaki near the largest Christian church in Japan at
1102 hours, August 9, 1945, with a yield estimated at 22 kilotons.
115.
Fat Man snapped trees at Nagasaki; the less powerful Hiroshima bomb only knocked them
down.
116.
Collecting the dead for cremation.
117.
A student exposed half a mile from the Nagasaki hypocenter.
118.
Flash burns, Nagasaki.
119.
Near the Nagasaki hypocenter, noon, August 10, 1945.
120.
Dr.
Michihiko Hachiya, director of the Hiroshima Communications Hospital.
His diary
chronicled the disaster.
121.
Emperor Hirohito decided after Nagasaki, over his ministers’ objections, to end the war
and cited “a new and most cruel bomb” in his August 15 surrender proclamation.
122.
Los Alamos received the Army-Navy E for excellence for its work.
123.
Mike I, the first true thermonuclear bomb, tested at Eniwetok in the Marshall Islands on
November 1, 1952.
Yield: 10.4 megatons (i.e., millions of tons of TNT equivalent).
Pipes carried
off radiation to diagnostic equipment; their arrangement confirms the linear Teller-Ulam
configuration.
Note man seated in foreground for scale.
124.
Mike vaporized the island of Elugelab and left a crater half a mile deep and two miles wide.
125.
The Mark 17 H-bomb, the first deliverable thermonuclear weapon.
Yield: megaton-range.
Weight: 21 tons.
126.
The Mike shot.
Its fireball expanded to a diameter of 3 miles.
127.
Early fireball of a postwar atomic bomb test.
“I could see a great bare eyeball,” Michihiko
Hachiya dreamed after Hiroshima, “bigger than life, hovering over my head, staring pointblank
at me.”
128.
Margrethe and Niels Bohr at their summer cottage in Tisvilde.
“We are in a completely new
situation that cannot be resolved by war.”
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PHOTO CREDITS
1.
Culver 2.
Egon Weiss 3.
E.
Scott Barr Collection, AIP Niels Bohr Library
4.
Courtesy Otto Hahn and Lawrence Badash, AIP Niels Bohr Library 5.
Mary Evans Rhodes 6.
Bibliothek und Archiv für Geschichte der Max-
Planck-Gesellscha 7.
Niels Bohr Institute 8/ 9.
Bibliothek und Archiv für Geschichte der Max-Planck-Gesellscha 10.
AIP Niels Bohr Library 11.
University of California Press 12.
Culver 13 /14.
Niels Bohr Institute 15 -17.
Emilio Segrè 18.
AIP Niels Bohr Library 19.
Picture People 20.
Niels Bohr Institute 21.
Société Française de Physique, Paris/AIP Niels Bohr Library 22.
W.
F.
Meggers Collection, AIP Niels Bohr Library 23/ 24.
Lawrence Berkeley Laboratory 25.
Photo by D.
Schoenberg, Bainbridge Collection, AIP Niels
Bohr Library 26.
Fraçoise Ulam 27.
Egon Weiss 28/ 29.
Rose Bethe 30.
Wide World 31.
Bibliothek und Archiv für Geschichte der Max-Planck-Gesellscha 32.
Segré Collection, AIP Niels Bohr Library 33 /34.
Bibliothek und Archiv für Geschichte der Max-Planck-Gesellscha 35.
Mary Evans
Rhodes 36.
Argonne National Laboratory 37.
Picture People 38.
Department of Terrestrial Magnetism, Carnegie Institution of Washington 39.
Wide
World
40.
Lawrence Berkeley Laboratory 41.
Picture People 42.
Rudolf Peierls 43.
Smithsonian Institution Science Service Collection, AIP Niels Bohr Library
44.
UPI/Bettmann Newsphotos 45.
UPI/Bettmann Newsphotos 46.
Alfred O.
C.
Nier 47.
Photo by P.
Ehrenfest, Weisskopf Collection, AIP Niels Bohr
Library 48.
Lawrence Berkeley Laboratory 49.
Picture People 50.
UPI/Bettmann Newsphotos 51.
Picture People 52.
Lawrence Berkeley Laboratory 53.
Argonne National Laboratory 54/ 55.
Martin Marietta 56.
Philip Abelson 57- 61.
National Archives 62 /63.
Norsk Hydro 64- 67.
Los Alamos National Laboratory 68.
Luis W.
Alvarez 69.
Niels Bohr Institute 70.
Françoise Ulam 77/72.
Los Alamos National Laboratory 73.
Oppenheimer Memorial Committee 74.
Emilio Segrè 75.
Picture People 76.
Picture People
77.
Mrs.
George Kistiakowsky 78 -83.
Los Alamos National Laboratory 84.
AIP Niels Bohr Library 85- 96.
Los Alamos National Laboratory
97.
USAF 98.
Picture People 99.
Henry L.
Stimson Papers, Yale University Library 100.
Robert Muldrow Cooper Library, Clemson University 101.
National Archives 102.
Harold Agnew 103- 105.
USAF 106.
Yoshito Matsushige 107.
Hiroshima Peace Memorial Museum 108 /109.
Hiroshima Peace Culture Foundation 110/ 111.
Hiroshima Peace Memorial Museum
112.
Hiroshima Peace Culture Foundation 113.
National Archives 114 /115.
Issei Nishimori 116.
Hiroshima Peace Memorial Museum 117.
Yosuke Yamabata 118.
Issei Nishimori 119.
Yosuke Yamabata 120.
Peter Wyden 121.
UPI/Bettmann Newsphotos 122- 126.
Los Alamos National Laboratory 127.
Dr.
Harold E.
Edgerton, MIT, Cambridge, MA 128.
Niels Bohr Institute
Notes
ABBREVIATIONS AND SOURCES:
OHI: Oral history interview.
AIP: Center for the History of Physics, American Institute of Physics,
New York, N.Y.
AHQP: Archives for the History of Quantum Physics, available at the AIP
and several other repositories.
Bush-Conant File: Vannevar Bush-James B.
Conant files, Office of
Scientific Research and Development, S-l (Record Group 227), National
Archives.
MED: Manhattan Engineer District Records (Record Group 77), National
Archives.
JRO Papers: J.
Robert Oppenheimer Papers, Library of Congress.
Strauss Papers: Lewis L.
Strauss Papers, Herbert Hoover Library, West
Branch, Iowa.
Szilard Papers: Leo Szilard Papers, University of California at San Diego.
Chapter 1: Moonshine
1.
September 12, 1933: I derive this date from Leo Szilard’s statement at
Szilard (1972), p.
529, that he read about Ernest Rutherford’s speech
to the British Association “one morning...
in the newspapers” and
“that day...
was walking down Southampton Row.” e British
Association story appeared prominently on p.
7 of e Times on
Sept.
12.
2.
“short fat man...
wives”: Szilard (1972), p.
xv.
3.
“Mr.
Wells...
justification”: e Times, p.
6.
4.
He knew Wells personally: Shils (1964), p.
38.
5.
Szilard read Wells’ tract: Weart and Szilard (1978), p.
22n.
6.
he traveled to London in 1929: ibid.
7.
Szilard bid: Shils (1964), p.
38.
8.
“I knew languages....mascot”: Weart and Szilard (1978), p.
4.
9.
“When I was young...
politics”: Szilard (1972), p.
xix.
10.
“I said to them...
this statement”: Weart and Szilard (1978), pp.
4-5.
11.
his clarity of judgment: ibid., p.
5.
12.
the Eötvös Prize: von Kármán and Edson (1967), p.
22.
13.
“no career in physics”: Weart and Szilard (1978), p.
5.
14.
“felt that his skill...
colleagues”: Wigner (1964), p.
338.
15.
saved his life: Weart and Szilard (1978), p.
8.
16.
“family connections”: ibid., p.
7.
17.
“Not long aerward...
disappeared”: ibid., p.
8.
18.
around Christmastime: ibid.
19.
“In the end...
’21”: ibid., p.
9.
20.
“As soon...
Einstein”: Wigner (1964), p.
338.
21.
Wigner remembers: ibid.
22.
Szilard won his attention: Segrè (1970), p.
106.
23.
von Laue...
accepted Szilard: Weart and Szilard (1978), Fig.
1, p.
10.
24.
“ere was snow...
strange”: de Jonge (1978), p.
125.
25.
“the air...
counted out”: ibid., p.
130.
26.
Press Ball: ibid., p.
132.
27.
Mies van der Rohe: Friedrich (1972), p.
163.
28.
Yehudi Menuhin: ibid., p.
219.
29.
George Grosz: Grosz (1923); Friedrich (1972), p.
152.
30.
“an elderly...
shoelaces”: quoted in ibid., p.
90.
31.
Fyodor Vinberg: ibid., pp.
95-96.
32.
“a dark...
enigma”: quoted in ibid., p.
190.
33.
“No, one...
gods”: de Jonge (1978), p.
99.
34.
“In order...
of inflation”: Elsasser (1978), pp.
31-32.
35.
“During a...
and opinion”: Wigner (1964), p.
337.
36.
“Berlin...
of physics”: Weart and Szilard (1978), p.
8.
37.
“In order...
original work”: ibid., p.
9.
38.
“I couldn’t...
to my mind”: ibid.
39.
Einstein, for example: Cf.
Einstein’s own evaluation: “Because of the
understanding of the essence of Brownian motion, suddenly all
doubts vanished about the correctness of Boltzmann’s [statistical]
interpretation of the thermodynamic laws.” Cited in Pais (1982), p.
100.
Cf.
also Szilard (1972), p.
31ff.
40.
“and I saw...
to do”: Weart and Szilard (1978), p.
9.
41.
“Well...
very much”: ibid., p.
9ff.
42.
“and next...
degree”: ibid., p.
11.
43.
Six months later: ibid.
44.
accepted as Habilitationsschri: Szilard (1972), p.
6.
45.
Szilard patents: ibid., pp.
697-706.
46.
“A sad...
valve”: Feld (1984), p.
676.
47.
pumping refrigerant: Weart and Szilard (1978), p.
12.
48.
January 5, 1929: Szilard (1972), p.
528.
49.
April 1, 1929: Childs (1968), p.
138ff.
50.
“the mid-twenties in Germany”: Weart and Szilard (1978), p.
22.
51.
“had a...
scale”: Snow (1981), p.
44.
52.
Der Bund: Weart and Szilard (1978), p.
23ff.
53.
“a closely...
spirit”: ibid., p.
23.
54.
“If we...
own”: ibid., p.
24.
55.
“take over...
parliament”: ibid., p.
25.
56.
“e Order...
state”: ibid., p.
28n.
57.
“e Voice of the Dolphins”: Szilard (1961).
58.
banding together: Weart and Szilard (1978), p.
22.
59.
“the parliamentary...
generations”: ibid.
60.
“I reached...
Switzerland”: ibid., p.
13.
61.
Chadwick Nature letter: Chadwick (1932a).
62.
Chadwick Proc.
Roy.
Soc.
paper: Chadwick (1932b).
63.
Szilard found orphan: Weart and Szilard (1978), p.
16.
64.
“the liberation...
bombs”: ibid.
65.
“oppressed...
application”: Wells (1914), p.
46.
66.
“is book...
time”: Weart and Szilard (1978), p.
16.
67.
“I met...
system”: ibid.
68.
Such must...
nuclear physics: ibid., pp.
12-13.
69.
“All I...
too bad”: ibid., p.
13.
70.
ings got...
Meitner: ibid.
71.
“ey all...
happening”: ibid.
72.
“He looked...
eyes”: ibid., p.
14.
73.
“I took...
day earlier”: ibid.
74.
£1595: Bank receipt dated 6 September 1933 in Szilard Papers.
75.
£854: Letter to “Béla” dated 31 August 1933 in Szilard Papers.
76.
“I was...
Association”: Weart and Szilard (1978), p.
17.
77.
“attempted...
developments”: e Times, p.
6.
78.
“Lord Rutherford...
irritated me”: Szilard (1972), p.
529.
79.
“is sort of...
Row”: Weart and Szilard (1978), p.
17.
80.
“I was...
be wrong”: Szilard (1972), p.
530.
81.
“It occurred...
may react”: ibid., p.
183.
82.
Polanyi: Semenoff (1935), p.
5.
83.
“As the light...
the street”: Szilard (1972), p.
530.
84.
“it suddenly...
atomic bombs”: Weart and Szilard (1978), p.
17.
Chapter 2: Atoms and Void
85.
“For by convention...
void”: quoted in Scientific American (1949), p.
49.
86.
“It seems...
formed them”: in Optics, quoted in Guillemin (1968), p.
15.
87.
“ough in...
and weight”: quoted in Pais (1982), p.
82.
88.
“It is...
pursuit in life”: Planck (1949), p.
13.
89.
“the process...
by any means”: ibid., p.
17.
90.
“us...
is settled”: W.
Ostwald, at a meeting of the Deutsche
Gesellscha für Naturforscher und Ärzte in 1895, quoted in Pais
(1982), p.
83.
91.
“e consistent...
finite atoms”: in 1883, quoted in ibid., p.
82.
92.
“What the atom...
as ever”: quoted in Chadwick (1954), p.
436.
93.
“republic of science”: Polanyi (1962).
94.
“a highly...
free society”: ibid., p.
5.
95.
“Millions are...
committed”: Polanyi (1974), p.
63.
96.
“the established...
letter”: Polanyi (1946), p.
43.
97.
“uncertainties...
nature”: ibid.
98.
“a full initiation”: ibid.
99.
“close personal...
master”: ibid.
100.
“what do we...
the world”: Feynman (1963), p.
2-1.
101.
“no one...
accepted”: Polanyi (1946), p.
45.
102.
“Any account...
is untrue”: Polanyi (1974), p.
51.
103.
an analogy: Polanyi (1962), p.
6ff.
104.
“Let them...
consequence”: ibid., p.
7.
105.
“growing points”: ibid., p.
15.
106.
“e authority...
above them”: ibid., p.
14.
His emphasis.
107.
“is network...
neighborhoods”: ibid.
108.
“Physics...
those events”: Wigner (1981), p.
8.
109.
three broad criteria: cf.
discussion in Polanyi (1962), p.
10ff.
110.
one thousand...
physicists: cf.
Segrè (1980), p.
9.
111.
“his genius...
astonished”: Chadwick (1954), p.
440.
Details of
Rutherford’s childhood selected from Eve (1939), Feather (1940)
and Crowther (1974).
112.
sickening insecurity: the phrase is C.
P.
Snow’s in Snow (1967), p.
11.
113.
“at’s the last potato”: Eve (1939), p.
11.
114.
“Now Lord...
mine”: ibid., p.
342.
115.
“Magnetization of...
discharges”: 1894, in Rutherford (1962), pp.
25-57.
116.
the world record: Marsden (1962), p.
3.
117.
“like an...
lion’s skin”: Eve (1939), p.
24.
118.
“A magnetic detector...
applications”: Rutherford (1962), pp.
80-
104.
119.
Marconi...
in September: cf.
Eve (1939), p.
35.
120.
“e reason...
the future”: ibid., p.
23.
121.
“You cannot serve...
time”: quoted in Kapitza (1980), p.
267.
122.
“one curious...
mistakes”: Snow (1967), p.
7.
123.
“I believe...
commercially”: Oliphant (1972), p.
140ff.
124.
“in his...
cultured man”: Marsden (1962), p.
16.
125.
“before tempting...
more”: ibid., p.
3.
126.
“I hope...
by myself”: Eve (1939), p.
34.
127.
Bank of England sealing wax: Blackett (1933), p.
72: “It is curious
that the most universally successful vacuum cement available for
many years should have been a material of common use for quite
other purposes.
At one time it might have been hard to find in an
English laboratory an apparatus which did not use red Bank of
England sealing-wax as a vacuum cement.”
128.
“the almost...
passes”: J.
J.
ompson in Conn and Turner (1965),
p.
53.
129.
“the corpuscle...
cathode ray”: Crowther (1974), p.
123.
130.
“a number...
electrification”: J.
J.
ompson in Conn and Turner
(1965), p.
97.
131.
ompson...
discovering X rays: cf.
ibid., p.
33.
132.
Frederick Smith: cf.
Andrade (1957), p.
444.
133.
“at a...
discharge-tube”: J.
J.
ompson in Conn and Turner (1965),
p.
33.
134.
Röntgen, Becquerel: these details from Segrè (1980), p.
19ff.
135.
“exposed...
on the negative”: quoted in ibid., p.
28.
136.
“expecting...
in the dark”: quoted in ibid., p.
29.
137.
“ere are...
[beta] radiation”: Rutherford (1962), p.
175.
138.
P.
V.
Villard: Segrè (1980), p.
50.
139.
“e McGill...
cannot complain”: Eve (1939), p.
57.
140.
In 1900...
radioactive gas: “A radioactive substance emitted from
thorium compounds.” Rutherford (1962), pp.
220-231.
141.
“At the beginning...
be examined”: Soddy (1953), p.
124ff.
142.
“conveyed the...
gas!”: ibid., p.
126.
143.
an “isotope”: Soddy (1913), p.
400.
144.
“for more than...
an institution”: Soddy (1953), p.
127.
145.
“similar...
cathode rays”: Rutherford (1962), p.
549.
146.
“It may...
molecular charge”: ibid., p.
606ff.
147.
“playful suggestion...
in smoke”: Eve (1939), p.
102.
148.
“some fool...
unawares”: ibid.
149.
“It is...
secret”: Soddy (1953), p.
95.
150.
“My idea...
romances”: quoted in Dickson (1969), p.
228.
151.
“Aer a very...
radium rays”: Eve (1939), p.
93.
152.
“I may...
keep going”: ibid., p.
123.
153.
“they are...
moving”: ibid., p.
127.
154.
“it remained...
true physicist”: R.
H.
Fowler, quoted in ibid., p.
429.
155.
An eyewitness: ibid., p.
183.
156.
reported the month before: “e Nature of the a Particle,” Nov.
3,
1908; Rutherford (1963), pp.
134-135.
157.
“Aer some days...
vessel”: ibid., p.
145.
158.
“In this...
style”: Russell (1950), p.
91.
159.
“I see...
his apparatus”: quoted in Eve (1939), p.
239.
160.
“supper in...
the motor”: Russell (1950), p.
88.
161.
his handshake: Oliphant (1972), p.
22.
162.
“he gave...
physical contact”: ibid.
163.
He could still be mortified: cf.
his response to the bishop in gaiters
who presumed to compare the South Island to Stoke-on-Trent in
Russell (1950), p.
96.
164.
“He was...
tricks”: ibid., p.
89.
165.
“Youthful...
fools gladly”: Weizmann (1949), p.
118.
166.
“Scattering of...
rays”: Feather (1940), p.
117.
167.
“I was...
to taste”: Eve (1939), p.
384.
168.
Philipp Lenard: cf.
Andrade (1957), p.
441.
169.
100 million volts: Rutherford’s calculation in 1906 cited in Feather
(1940), p.
131.
170.
“Such results...
electrical forces”: ibid.
171.
rang a bell: Blackett (1933), p.
77.
172.
But the experiment was troubled: details from Marsden (1962), p.
8ff.
173.
“See if...
surface”: ibid., p.
8.
174.
“I remember...
told him”: ibid.
175.
“If the...
be required”: H.
Geiger and E.
Marsden, “On a diffuse
reflection of α-particles” in Conn and Turner (1965), p.
135ff.
176.
a first quick intuition: cf.
Norman Feather in Rutherford (1963), p.
22.
177.
“It was...
minute nucleus”: quoted in Conn and Turner (1965), p.
136ff.
178.
sheets of good paper: cf.
photographs of these historic notes in
Rutherford (1963), following p.
240.
179.
a model...
pendulum: cf.
Eve (1939), p.
197.
180.
“largely...
people”: Chadwick OHI, AIP, p.
11.
181.
a rare snake: ibid.
Cf.
also Chadwick (1954), p.
442n.
182.
“a most...
it”: Chadwick OHI, AIP, p.
12.
183.
“a central...
in amount”: Rutherford (1963), p.
212.
184.
Nagaoka had postulated: cf.
Conn and Turner (1965), p.
112ff, for
partial text.
185.
“Campbell tells...
optical effects”: quoted in Feather (1940), p.
136.
186.
“supposed to...
rotating electrons”: Rutherford (1963), p.
254.
187.
“for the...
in Manchester”: Nagaoka refers in his letter to “your
paper on the calculation of alpha particles which was in progress
when I visited Manchester.” at paper, “e number of a particles
emitted by uranium and thorium and by uranium minerals,” was
written with Hans Geiger, appeared in the Philosophical Magazine in
Oct.
1910 and was sent July 1910.
For the text of Nagaoka’s letter cf.
Eve (1939), p.
200.
188.
the same theoretical defect: cf.
discussion in Heilbron and Kuhn
(1969), p.
241ff.
189.
“Bohr...
radioactive work”: Eve (1939), p.
218.
Chapter 3: Tvi
190.
Tvi: conversations with Josiah ompson greatly enlightened this
discussion.
191.
“ere came...
Niels Bohr!”: Eve (1939), p.
218.
192.
“an enormous...
head”: Snow (1981), p.
19.
193.
“much more...
later years”: ibid.
194.
“he took...
the matter”: quoted in Rozental (1967), p.
78.
195.
“uttering his...
truth”: quoted in Pais (1982), p.
417.
196.
“his assurance...
vivid images”: Frisch (1979), p.
94.
197.
“he would...
as criticism”: quoted in Rozental (1967), p.
79.
198.
“Not oen...
of trance”: quoted in Pais (1982), pp.
416-417.
199.
“gloomy...
smile”: quoted in Rozental (1967), p.
215.
200.
“keen worshipper”: Harald Høffding, quoted in ibid., p.
13.
201.
“lovable personality”: the surgeon Ole Chievitz, quoted in ibid., p.
15.
202.
great interrelationships: Petersen (1963), p.
9: “Bohr has said that as
far back as he could remember he liked to dream of great
interrelationships.”
203.
speaking in paradoxes: according to Høffding in his Memoirs,
quoted in Rozental (1967), p.
13.
204.
“I was...
different character”: Bohr OHI, AIP, p.
1.
205.
“At a...
his imagination”: Rozental (1967), p.
15.
206.
“the special...
the family”: quoted in ibid.
207.
“Even as...
fundamental problems”: Petersen (1963), p.
9.
208.
trouble learning to write: cf.
Segrè (1980), p.
119.
209.
“ere runs...
two brothers”: Rozental (1967), p.
23.
210.
“à deux”: Vilhelm Slomann, quoted in ibid., p.
25.
211.
“In my...
than I”: Bohr OHI, AIP, p.
1.
212.
Harald...
told whoever asked: cf.
for example Richard Courant in
Rozental (1967), p.
301.
213.
a stick used as a probe: e.g., Rozental (1967), p.
306.
214.
“believed literally...
of faith”: quoted in ibid., p.
74.
215.
“I see...
his heart”: quoted without citation in Moore (1966), p.
35.
Moore was allowed access to some of Bohr’s unpublished private
correspondence.
216.
Bohr draed...
private letters: cf.
Rozental (1967), p.
30.
217.
“If the...
will come”: quoted in Cline (1965), p.
214.
218.
Bohr’s anxiety: this discussion is based on Lewis S.
Feuer’s excellent analysis in Feuer (1982) but differs in emphasis and to some extent
in conclusions.
Holton (1973) is also an essential source.
219.
“a young...
unusual resolution”: quoted in Rozental (1967), p.
74.
220.
“an unfinished...
in [Denmark]”: Bohr (1963), p.
13.
221.
“a remarkably...
position [as human beings]”: ibid.
222.
“Every one...
his initiation”: quoted in Rozental (1967), p.
121.
223.
“very soberly...
social activities”: Bohr (1963), p.
13.
224.
“[I start]...
bottomless abyss”: ibid.
225.
“Bohr kept...
studies itself”: Oppenheimer (1963), II, pp.
25-26.
226.
“Certainly I...
to madness”: quoted in Rosenfeld (1963), p.
48.
227.
“us on...
becomes actor”: quoted in ibid., p.
49.
228.
“Bohr would...
emphasized”: Rozental (1967), p.
121.
229.
the image that recurred: cf.
ibid., pp.
77, 327-328.
Examples abound
in the written record.
230.
“suspended in language”: quoted in Petersen (1963), p.
10.
231.
“Nur die...
die Wahrheit”: quoted in Holton (1973), p.
148.
232.
“I took...
with Høffding”: Bohr OHI, AIP, p.
1.
233.
Harald Høffding: cf.
biographical note at Bohr (1972), p.
xx.
234.
“despair”: Holton (1973) notes this confession on p.
144.
235.
Møller taught Kierkegaard: cf.
ompson (1973), p.
88.
236.
“my youth’s...
departed friend”: quoted in ibid.
237.
e Danish word...
“ambiguity”: paraphrased from ibid., p.
155.
238.
“His leading...
the individual”: quoted in Holton (1973), p.
146.
239.
“Only in...
of continuity”: quoted in ibid., p.
147.
240.
“At that...
multivalued functions”: Bohr OHI, AIP, p.
1.
241.
the solid work: cf.
Bohr (1972), p.
4.
242.
“took such...
the flame”: Rosenfeld (1979), p.
325.
243.
“the experiments...
the paper”: quoted in Rosenfeld (1963), p.
39.
244.
“not a professor”: Bohr (1972), p.
10.
245.
“is is...
ever read”: ibid., p.
501.
246.
“envy would...
the rooops”: ibid., p.
95, adjusting the idiom.
247.
“four months...
rough dras”: ibid.
248.
“unpractical”: Bohr OHI, AIP, p.
2.
249.
“He made...
something good”: quoted in Nielsen (1963), pp.
27-28.
250.
“in deepest...
my father”: Bohr (1972), p.
295.
251.
“Dr.
Bohr...
a record”: quoted in ibid., pp.
98-99.
252.
“Oh Harald!...
little fireplace”: ibid., p.
519.
253.
“under threat...
stand it”: ibid., p.
523.
254.
“for an...
blustering wind”: quoted in Rozental (1967), p.
44,
adjusting the idiom.
255.
“absolute geniuses...
you out”: quoted in ibid., p.
40.
256.
“I wonder...
his ideas”: quoted in Moore (1966), p.
32.
257.
“I’m longing...
silly talk”: quoted in ibid., p.
33.
258.
“It takes...
was different”: Bohr OHI, AIP, pp.
13-14.
259.
“came down...
his name”: Bohr (1963), p.
31.
My chronology of
Bohr’s visits to Manchester and his arrangements to work there
generally follows the plausible conjectures of Heilbron and Kuhn
(1969), p.
233, n.
57.
260.
“just then...
atomic nucleus”: Bohr (1963), p.
31.
261.
Bohr had matters on his mind: cf.
his letter to C.
W.
Oseen on Dec.
1, 1911: “I am at the moment very enthusiastic about the quantum
theory (I mean its experimental side), but I am still not sure this is
not due to my ignorance.” Quoted in Heilbron and Kuhn (1969), p.
230, with a following discussion.
262.
“the patience...
his mind”: Bohr (1963), p.
32.
263.
“one of...
of Rutherford”: ibid., p.
31.
264.
“Bohr’s different...
football player!”: quoted in Rozental (1967), p.
46.
265.
eleven Nobel Prize winners: cf.
Zuckerman (1977), p.
103.
266.
Manchester is always here: cited by A.
S.
Russell in Birks (1962), p.
93ff.
267.
“an introductory...
research”: Bohr (1963), p.
32.
268.
Bohr learned about radiochemistry: cf.
ibid., pp.
32-33.
269.
“Rutherford...
thought...
his atom”: Bohr OHI, AIP, p.
13.
270.
“Ask Bohr!”: quoted in Rozental (1967), p.
46.
271.
“It could...
quickly”: Heilbron and Kuhn (1969), p.
238; Bohr
(1972), p.
559; selecting the most idiomatic phrases from each
translation.
272.
“getting along...
to you!”: Bohr (1972), p.
561, adjusting the idiom.
273.
July 22: Bohr to Harald Bohr, ibid.
274.
“to be...
few weeks”: quoted in Heilbron and Kuhn (1969), p.
256.
275.
“a very...
these things”: quoted in ibid.
276.
“One must...
mechanical sort”: quoted in ibid., p.
214.
My
discussion here generally follows this excellent monograph.
277.
“Later measurements...
to be”: Planck (1949), p.
41.
278.
“a universal...
of action”: ibid., p.
43.
279.
“e spectra...
a butterfly”: quoted in Heilbron and Kuhn (1969),
p.
257, n.
117.
280.
“As soon...
to me”: quoted in ibid., p.
265.
281.
“ere is...
its advent”: Darrow (1952), p.
53.
282.
“ere appears...
to stop”: quoted in Bohr (1963), p.
41.
283.
“Every change...
possible transitions”: quoted in Feuer (1982), p.
137.
284.
“principal assumptions”: cf.
Shamos (1959), p.
338.
285.
“Bohr characteristically...
phenomena”: Rosenfeld (1979), p.
318.
286.
“asking questions of Nature”: Rosenfeld (1963), p.
51.
287.
“I try...
I think”: Oppenheimer (1963), I, p.
7.
288.
“He points...
their validity”: Rosenfeld (1979), p.
318.
289.
“the fairyland of the imagination”: quoted in ompson (1973), p.
176.
290.
“It is...
about nature”: Petersen (1963), p.
12.
291.
“It was...
so seriously”: Bohr OHI, AIP, p.
13.
Chapter 4: The Long Grave Already Dug
292.
October 23, 1912: Hahn (1966), p.
70.
Hahn (1970), p.
102, says Oct.
12.
e official program confirms the later date.
293.
a wet day, etc.: cf.
photo “e dedication of the Kaiser Wilhelm Institute for Chemistry” in Hahn (1966), following p.
72.
294.
the Kaiser Wilhelm Society: details from Haber (1971), pp.
49-50.
295.
an embarrassment: cf.
Hahn (1966), p.
50.
296.
Hahn admired women: cf.
Hahn (1970), passim.
297.
For details of Meitner’s early life: cf.
Frisch (1979), p.
3.
298.
“ere was...
close friends”: Hahn (1970), p.
88.
299.
“an emanating...
screen”: Hahn (1966), p.
71.
300.
“If I...
in prison”: Hahn (1970), p.
110.
301.
“worthy of...
noble brows”: quoted in ibid., p.
102.
302.
Moseley: this discussion relies on Heilbron (1974).
303.
“so reserved...
like him”: quoted in ibid., p.
57.
304.
“Hindoos, Burmese...
‘scented dirtiness’ ”: Moseley to his mother,
ibid., p.
176.
305.
“Some Germans...
photographing them”: ibid., p.
193.
306.
“We find...
the atom”: ibid., p.
205.
307.
“unbearably hot...
start measurements”: ibid., p.
206.
308.
“I want...
a thousand”: ibid., pp.
207-208.
309.
a billiard table: Bohr OHI, AIP, p.
7.
310.
“And that...
were away”: ibid.
311.
“the only...
of success”: quoted in Rozental (1967), p.
58.
312.
“a definite...
chemical properties”: quoted in Eve (1939), p.
224.
313.
“shy...
and noble”: ibid., p.
223.
314.
“great developments...
on mankind”: quoted in ibid., p.
224.
315.
“do not...
and ‘fantastic’ ”: Bohr (1972), p.
567.
316.
“Speaking with...
saying so”: quoted in Eve (1939), p.
226.
317.
“During the...
on Physics”: Heilbron (1974), pp.
211-213.
318.
“Because you...
from Moseley”: Bohr OHI, AIP, p.
4.
319.
Bayer Dye Works: cf.
Haber (1971), p.
128.
320.
“In the...
thermos vessels”: Hahn (1970), p.
107.
321.
“It is...
whole valley”: quoted in Rozental (1967), p.
64.
322.
“e eleven-...
of Palestine”: quoted in Weisgal and Carmichael
(1963), p.
20.
323.
“a deliberate...
‘eternal students’ ”: Weizmann (1949), p.
93.
324.
“inviting every...
remuneration”: ibid., p.
171.
325.
“In the...
thrown away”: ibid., p.
134.
326.
January 1915: Stein (1961), p.
140.
327.
“Really messianic...
upon us”: quoted in ibid., p.
137n.
328.
“You know...
your hands”: quoted in Weizmann (1949), p.
171.
329.
“So it...
British Admiralty”: ibid., p.
172.
Weizmann writes 1916,
but this is clearly a slip of memory.
Cf.
Stein (1961), p.
118.
Churchill was no longer First Lord in 1916.
330.
“brisk, fascinating...
two years”: Weizmann (1949), p.
173.
331.
“Horse-chestnuts...
for maize”: Lloyd George (1933), pp.
49-50.
332.
“When our...
in Palestine”: ibid., p.
50.
Vera Weizmann affirmed
the authenticity of this conversation; cf.
Stein (1961), p.
120n.
333.
“view with...
this object”: cf.
frontispiece facsimile, Stein (1961).
334.
“outstanding war...
National Home”: quoted in ibid., p.
120n.
335.
“it being...
in Palestine”: ibid., frontispiece facsimile.
336.
a German rocket signal, etc.: these details at Lefebure (1923), pp.
36-
37; Goran (1967), p.
68; and Hahn (1970), pp.
119-120.
337.
“to abstain...
deleterious gases”: Carnegie Endowment for
International Peace (1915), p.
1.
338.
300,000 pads: Pound (1964), p.
131.
339.
Otto Hahn helped: cf.
Hahn (1970), p.
118ff.
340.
5,730 of them: Prentiss (1937), p.
148.
341.
“Haber informed...
gas-warfare”: Hahn (1970), p.
118.
342.
James Franck: according to ibid., p.
119ff.
343.
I.
G.
Farben: cf.
Lefebure (1923), p.
86; Haber (1971), pp.
279-280.
344.
mid-June 1915: as Hahn remembers it in Hahn (1970), p.
120.
Prentiss (1937) says phosgene was first used by the Germans in a
cloud-gas attack against the British at Nieltje on Dec.
19, 1915.
Hahn may have meant 1916.
345.
“the wind...
success”: Hahn (1970), p.
120.
346.
buying German dyestuffs: cf.
Haber (1971), p.
189.
347.
phosgene: cf.
Prentiss (1937), p.
154ff.
348.
chlorpicrin: cf.
ibid., p.
161ff.
349.
mustard gas: cf.
ibid., p.
177.
350.
a typical artillery barrage: estimated from the figures given at
Lefebure (1923), pp.
77-80.
351.
“She began...
of life”: Goran (1967), p.
71.
352.
a scientist belongs: according to ibid.
353.
“Our destination...
in doubt”: Heilbron (1974), p.
271.
354.
“to be...
or systematizing”: ibid., p.
271ff.
355.
“full of...
and Australians”: ibid., p.
272.
356.
“e one...
food”: ibid., p.
274.
357.
“over ghastly...
slippery inclines”: G.
E.
Chadwick, quoted in ibid.,
p.
122.
358.
“ey came...
e Farm”: Masefield (1916), p.
206.
359.
“one of...
in history”: quoted in Kevles (1979), p.
113.
360.
Folkestone: this section relies primarily on Fredette (1976).
361.
“I saw...
the sight”: quoted in ibid., pp.
20-21.
362.
“You must...
in war”: quoted in ibid., p.
30.
363.
“a basis...
to fight”: ibid., p.
39.
364.
“e day...
and subordinate”: quoted in ibid., p.
111.
365.
research contracts: Prentiss (1937), p.
84.
366.
“the great...
of warfare”: Lefebure (1923), p.
173.
367.
a vast war-gas arsenal: cf.
Prentiss (1937), p.
85, for these details and
statistics.
368.
“Had the...
war”: Lefebure (1923), p.
176.
369.
500,000...
300,000: cf.
Ellis (1976), p.
62.
370.
170 million rounds: ibid.
371.
“Concentrated essence of infantry”: J.
F.
C.
Fuller, quoted in Keegan
(1976), p.
228.
372.
“I go...
others”: Edmund Blunden, quoted in Ellis (1975), pp.
137-
138.
373.
21,000 men: cf.
Keegan (1976), p.
255.
374.
“It bears...
common needle”: quoted in Ellis (1975), p.
16.
375.
“For the...
working shi”: Keegan (1976), pp.
229-230.
376.
a soware package: this discussion benefits from Elliot (1972), p.
20ff.
377.
“e basic...
trenches”: ibid., p.
20.
378.
“e War...
of victims”: Sassoon (1937), II, p.
143.
379.
the long grave already dug: Masefield (1916), p.
104.
380.
“e war...
human variation”: Elliot (1972), p.
23.
381.
Elliot stresses: ibid., p.
25.
Chapter 5: Men from Mars
382.
“Horse-drawn...
social currents”: von Kármán (1967), p.
14.
383.
“the fountain...
to oppression”: Paul Ignotus, quoted in Fermi
(1971), pp.
38-39.
384.
33 percent...
illiterate: Jászi (1924), p.
7.
385.
37.5 percent of...
arable land: McCagg (1970), p.
186.
386.
1910 statistics: cf.
Nagy-Talavera (1970), p.
41n.
387.
S.
V.
Schossberger: cf.
McCagg (1970), p.
132.
My discussion of this
phenomenon generally follows McCagg.
388.
“one day...
almost unpronounceable”: von Kármán (1967), p.
17.
389.
Jewish family ennoblements: cf.
McCagg (1970), p.
63.
390.
“galaxy of...
lived elsewhere”: Frisch (1979), pp.
173-174.
391.
Von Kármán at six: von Kármán (1967), pp.
15-16.
392.
Von Neumann at six: cf.
Goldstine (1972), pp.
166-167.
393.
Edward Teller...
late...
to talk: cf.
Blumberg and Owens (1976), p.
6.
394.
“Johnny used...
improved”: Ulam (1976), p.
111.
395.
“As a...
were good”: Teller (1962), p.
81.
396.
“addiction to...
of Man”: Weart and Szilard (1978), p.
4.
397.
“the most...
19th century”: E.
F.
Kunz, quoted in Madach (1956), p.
7.
398.
“In [Madach’s]...
is pessimistic”: New York Post, Nov.
24, 1945, quoted in Weart and Szilard (1978), p.
3n.
399.
“a society...
achievement”: Smith (1960), p.
78.
400.
“My father...
them ourselves”: von Kármán (1967), p.
21.
401.
“We had...
mathematician”: interview with Eugene Wigner,
Princeton, N.J., Jan.
21, 1983.
402.
Teller recalls...
syllogism: cf.
Blumberg and Owens (1976), p.
137.
403.
At Princeton: cf.
Goldstine (1972), p.
176.
404.
even Wigner thought: cf.
Heims (1980), p.
43.
405.
the only authentic genius: cf.
Fermi (1971), pp.
53-54.
406.
“So you...
like geniuses”: Blumberg and Owens (1976), pp.
15-16.
407.
“I think...
impressed me”: ibid., p.
23.
408.
“e Revolution...
irresistible momentum”: Ferenc Göndör,
quoted in Völgyes (1971), p.
31.
409.
“Es ist passiert”: quoted in ibid., p.
12.
410.
“the rousing...
melodious flood”: Koestler (1952), p.
63.
411.
“So far...
sadistic excesses”: von Kármán (1967), p.
93.
412.
“because it...
to come”: Koestler (1952), p.
67.
413.
“We le...
put down”: USAEC (1954), p.
654.
414.
the group of Hungarian financiers: McCagg (1970), p.
16.
415.
Teller heard of corpses: Blumberg and Owens (1976), p.
18.
416.
e Tellers acquired two soldiers: cf.
ibid.
417.
“I shiver...
terrible revenge”: quoted in ibid., p.
19.
418.
five hundred deaths: I use Koestler’s figure (“under five hundred”),
the larger of the two I have found.
Koestler (1952), p.
67.
419.
at least five thousand deaths: Heims (1980), p.
47, citing Rudolf L.
Tökes, Béla Kun and the Hungarian Soviet Republic (Praeger, 1967),
p.
214.
420.
“no desire...
all question”: Jászi (1923), p.
160, the atrocities in
detail ff.
421.
“that the...
nationalities”: quoted in ibid., p.
186.
422.
“It will...
face extinction”: Ulam (1976), p.
111.
423.
“dinned into...
stay even”: Time, Nov.
19, 1957, p.
22.
424.
“I loved...
doomed society”: Cough-Ian (1963), p.
89.
425.
“I was...
is lasting”: von Kármán (1967), p.
95.
426.
“once commented...
the ‘it’ ”: Pais (1982), p.
39.
427.
“the acquisition...
hostile world”: Weizmann (1949), p.
18.
428.
“every division...
a watershed”: ibid., p.
29.
429.
“In the...
little understanding”: Born (1981), p.
39.
430.
“Only a...
the maze”: Segrè (1980), p.
124.
431.
“Bohr remembered...
of Maxwell”: Oppenheimer (1963), I, p.
21.
432.
“His reactions...
as well”: Rozental (1967), p.
138.
433.
“at...
of thought”: quoted in Segrè (1980), p.
124.
434.
“a unique...
unforgettable experience”: Bohr (1963), p.
54.
435.
“I shall...
highly exciting”: Heisenberg (1971), pp.
37-38.
436.
“At the...
that aernoon”: ibid., p.
38.
437.
“Suddenly, the...
of hope”: ibid., p.
42.
438.
“You are...
small children!”: Gamow (1966), p.
51.
439.
“radiant...
walking shorts”: quoted in Jungk (1958), p.
26.
440.
“But now...
very seriously”: Heisenberg (1971), p.
55.
441.
“It saddened...
such fancies”: ibid., p.
8.
442.
“a few...
to rise”: ibid., p.
61.
443.
“a coherent...
atomic physics”: ibid., p.
62.
444.
“is was...
scholarship”: the interviewer was omas Kuhn, in
1963, quoted in Smith and Weiner (1980), p.
3.
445.
one of Robert’s friends: Francis Fergusson, cited in ibid., p.
2.
446.
“desperately amiable...
be agreeable”: Paul Horgan, quoted in ibid.
447.
“an unctuous...
a bastard”: quoted in Royal (1969), pp.
15-16.
448.
“tortured him”: quoted in ibid., p.
23.
449.
“Still a...
about him”: Jane Didisheim Kayser, quoted in Smith and
Weiner (1980), p.
6.
450.
“came down...
the time”: ibid., p.
7.
451.
a Goth coming into Rome: Royal (1969), p.
27.
452.
“He intellectually...
the place”: quoted in ibid.
Michelmore (1969), p.
11, however, has Oppenheimer himself saying: “I...
just raided
the place intellectually.”
453.
a typical year: cf.
Smith and Weiner (1980), p.
45.
454.
“although I...
with murder”: ibid., p.
46.
455.
“the most...
came alive”: Michelmore (1969), p.
11.
456.
“Up to...
of wrong”: Seven Springs Farm transcript, p.
5, in JRO
Papers, Box 66.
457.
“Generously, you...
dead.
Voila”: Smith and Weiner (1980), p.
54.
458.
Both of Oppenheimer’s...
friends: they are quoted in this regard in
ibid., p.
32.
459.
“It came...
in physics”: ibid., pp.
45-46.
460.
“a man...
an apprentice”: ibid., p.
69.
461.
“But Rutherford...
the center”: ibid., p.
75.
462.
“perfectly prodigious...
success”: quoted in ibid., p.
77.
463.
“I am...
Harvard overnight”: ibid., p.
87.
464.
“e business...
interested in”: ibid, p.
88ff.
465.
“e melancholy...
been snubbed”: ibid., p.
128.
466.
“How is...
worth living”: ibid., p.
86.
467.
“making a...
a career”: ibid., p.
90.
468.
“on the...
was chronic”: quoted in Royal (1969), p.
35.
469.
“noisy...
me crazy”: Smith and Weiner (1980), p.
92.
470.
“doing a...
and alarm”: John Edsall, quoted in ibid.
471.
“When Rutherford...
at’s bad”: ibid., p.
96.
472.
“sweetness”: Snow (1981), p.
60.
473.
“At that...
theoretical physicist”: Smith and Weiner (1980), p.
96.
474.
“He said...
probably true”: quoted in ibid., p.
94.
475.
“a great...
to brigantines”: ibid., p.
95.
476.
“e [Cambridge]...
but love”: quoted in Davis (1968), p.
22.
477.
“a great...
it”: quoted in ibid., p.
21.
478.
“Although this...
very much”: Smith and Weiner (1980), p.
103.
479.
“Not only...
for generations”: Teller (1980), p.
137.
480.
“a desert”: second AHQP interview, p.
18.
481.
“largeness and...
fixed up”: Smith and Weiner (1980), p.
121.
482.
“house and...
and stream”: ibid., p.
126.
483.
Everyone went...
except Einstein: Segrè (1980) gives Einstein’s
reason at p.
168.
484.
“In other...
same structure”: Heisenberg (1971), p.
71.
485.
“is hypothesis...
be true”: ibid., p.
72.
486.
“with...
liberation”: ibid., p.
71.
487.
“Wilhelm Wien...
by Schrödinger”: Heisenberg in Rozental (1967),
p.
103.
488.
“For though...
laborious discussions”: ibid.
489.
“While Mrs....
admit that”: Heisenberg (1971), pp.
75-76.
490.
“If one...
step forward”: quoted in Rozental (1967), pp.
103-104.
491.
“utterly...
all along”: Heisenberg (1971), p.
77.
492.
“It is...
can observe”: quoted in ibid.
493.
“On this...
quantum mechanics”: Heisenberg in Rozental (1967), p.
105.
494.
Bohr ought to have liked: cf.
Heisenberg’s discussion in ibid., p.
106.
495.
“the great...
scientists”: Bohr (1961), p.
52.
496.
“renunciation”: e.g., ibid., pp.
77, 80.
497.
“Two magnitudes...
the other”: Segrè (1980), p.
167.
498.
“bears a...
and object”: Bohr (1961), p.
91.
499.
“quantum mechanics...
play dice”: quoted in Holton (1973), p.
120.
500.
“We all...
it all”: Heisenberg (1971), p.
79.
501.
“ ‘God does...
the last”: ibid., p.
80.
502.
“Nor is...
the world”: quoted in ibid., p.
81.
Chapter 6: Machines
503.
“I shall...
world”: Snow (1958), p.
88.
504.
“uncarpeted floor...
volcano”: Oliphant (1972), p.
19.
505.
“An anomalous effect in nitrogen”: Rutherford (1963), p.
585ff.
506.
“gave rise...
itself”: ibid., p.
547.
507.
“I occasionally...
this method”: quoted in Bohr (1963), p.
50.
508.
“appeared to...
H scintillations”: Rutherford (1963), p.
585.
509.
“must be...
in air”: ibid., p.
587.
510.
“From the...
is disintegrated”: ibid., p.
589.
511.
one...
in 300,000: Rutherford (1965), p.
24.
512.
Francis William Aston: biographical details from de Hevesy (1947).
513.
“In this...
discharge tube”: ibid., p.
637.
514.
building the precision instrument: cf.
Aston (1927, 1933).
515.
“In letters...
atomic model”: Bohr (1963), p.
52.
516.
“that neon...
to 1”: Aston (1938), p.
105.
517.
“High packing...
the reverse”: Aston (1927), p.
958.
518.
“If we...
full speed”: Aston (1938), p.
106.
519.
“the nuclear...
door neighbor”: ibid., pp.
113-114.
520.
“Stockholm...
ever since”: quoted in de Hevesy (1947), p.
645.
521.
“particularly detested...
barking kind”: quoted in ibid., p.
644.
522.
“What is...
not answer”: quoted in Kevles (1977), p.
96.
Numbers
of American physicists given here and ff.
523.
Psychometricians: e.g., Eiduson (1962), Goodrich et al.
(1951), Roe
(1952) and Terman (1955).
524.
IQ scores: cf.
Roe (1952), p.
24.
525.
“He is...
his nature”: ibid., p.
22.
526.
A psychological examination: Eiduson (1962).
527.
“their fathers...
knew them”: ibid., p.
65.
528.
“rigid...
reserved”: ibid., p.
22.
529.
“shy, lonely...
or politics”: Terman (1955), p.
29.
530.
a fatherly science teacher: cf.
Goodrich et al.
(1951), p.
17.
531.
“masterfulness...
dignity”: ibid.
532.
“It would...
their students”: ibid.
533.
Ernest Orlando Lawrence: biographical details from Alvarez (1970),
Childs (1968) and Davis (1968).
534.
“almost...
mathematical thought”: Alvarez (1970), p.
253.
535.
“it seemed...
atomic nucleus”: Lawrence (1951), p.
430.
536.
“the tedious...
electron volts”: Alvarez (1970), p.
260.
537.
“In his...
aer night”: ibid., p.
261.
538.
“is new...
arrangement”: Lawrence (1951), p.
431.
539.
“It struck...
magnetic field”: Alvarez (1970), p.
261.
540.
“Oh, that...
your own”: quoted in Davis (1968), p.
19.
541.
“I’m going...
famous!”: quoted in Childs (1968), p.
140.
542.
a battered gray Chrysler: cf.
Smith and Weiner (1980), p.
135.
543.
“unbelievable vitality...
the opposite”: quoted in Childs (1968), p.
143.
544.
“e intensity...
was before”: quoted in Davis (1968), p.
38.
545.
“having a...
about 300” : Lawrence and Livingston (1932), p.
32.
546.
“Assuming then...
do this”: ibid., p.
34.
547.
Oppenheimer told a friend: cf.
Davis (1968), p.
23.
548.
“men of...
broad intuition”: Rabi (1969), p.
7.
549.
the tunnel effect: cf.
Bethe (1968), p.
393: “is work led him on to a
treatment of the ionization of the hydrogen atom by electric fields,
probably the first paper describing the penetration of a potential
barrier.”
550.
dying suns: e.g.
Oppenheimer and Snyder (1939).
551.
“You put...
know peace”: Smith and Weiner (1980), pp.
155-156.
552.
“Interested to...
the circumstances”: quoted in Childs (1968), p.
174.
553.
“uncommon sensitivity...
of thinking”: Eiduson (1962), p.
105-106.
554.
“Were this...
such fantasying”: ibid., p.
106.
555.
“is discovery...
in him”: Pais (1982), p.
253.
556.
“But if...
about them”: quoted in Rozental (1967), p.
139.
557.
“And Bohr...
not quite’ ”: Oppenheimer (1963), I, p.
3.
558.
e Bakerian Lecture: “Nuclear constitution of atoms” in
Rutherford (1965), p.
14ff.
559.
“the possible...
intense field”: ibid., p.
34.
560.
James Chadwick: biographical details in Massey and Feather (1976).
Cf.
also Chadwick’s various recollections.
561.
“was hardly...
of Moseley”: Massey and Feather (1976), p.
50.
562.
“But also...
Soldiers’ ”: Chadwick (1954), p.
443.
563.
“Before the...
neutral particle”: Chadwick OHI, AIP, pp.
35-36.
564.
“And so...
only occasionally”: ibid., p.
36.
565.
“It was...
disposal”: Oliphant (1972), p.
67.
566.
“dour and...
became apparent”: ibid., p.
68.
567.
“to conceal...
gruff façade”: quoted in Wilson (1975), p.
57.
568.
“He had...
chuckle”: Massey and Feather (1976), p.
66.
569.
“the physics...
noisy”: ibid., p.
12.
570.
he said later: paraphrased in ibid., p.
15.
571.
“were so...
of alchemy”: Chadwick (1964), p.
159.
572.
“passed through...
be found”: Chadwick (1954), p.
445.
573.
“the problem...
to believe”: ibid., p.
444.
574.
“was a...
really important”: James Chadwick OHI, AIP, p.
49.
575.
“We are...
physics!”: Snow (1967), p.
3.
576.
“We are...
complex atoms”: Rutherford (1965), p.
181.
577.
the scintillation method: this discussion follows Feather (1964), esp.
p.
136ff.
578.
“He found...
while counting!”: Massey and Feather (1976), p.
19.
579.
“e loss...
of them”: Eve (1939), p.
341.
580.
his armorial bearings: cf.
illustration and description in ibid., p.
342.
581.
“a real...
physicist”: Segrè (1980), p.
180.
582.
“I don’t...
he did”: James Chadwick OHI, AIP, p.
70.
583.
“Indeed...
element investigated”: Feather (1964), p.
138.
584.
“that the...
backward direction”: James Chadwick OHI, AIP, p.
161.
585.
“And that...
the neutron”: James Chadwick OHI, AIP, p.
71.
586.
“Of course...
very much”: ibid.
587.
“together...
in Paris”: Feather (1964), p.
142.
588.
“ey fitted...
hydrogenous material”: ibid., p.
140.
589.
“Not many...
strange”: Chadwick (1964), p.
161.
590.
e radiation source: cf.
photograph at Crowther (1974), p.
196.
591.
“For the...
oscillograph record”: Feather (1964), p.
141.
592.
“the number...
protons”: Chadwick (1932b), p.
695.
593.
“In this...
were tested”: ibid.
594.
“Hydrogen...
this way”: ibid., p.
696.
595.
“In general...
of 1920”: ibid., p.
697.
596.
“It was...
time”: James Chadwick OHI, AIP, p.
71.
597.
“But there...
the letter”: ibid., p.
72.
598.
“To [Chadwick’s]...
physicist”: Segrè (1980), p.
184.
599.
at Wednesday: the Kapitza Club traditionally met on Tuesday, but
I take it that Chadwick finished the first intense phase of his work
with the writing of his letter to Nature dated this day, Feb.
17, 1932.
His remark about wanting to be chloroformed (see below) indicates
he had not yet rested from his ten-day marathon.
600.
“a very...
us all”: Oliphant (1972), p.
76.
601.
“one of...
a fortnight”: Snow (1981), p.
35.
602.
“A beam...
times faster”: Morrison (1951), p.
48.
603.
“the prehistory...
nuclear physics”: Bethe OHI, AIP, p.
3.
604.
“the personification...
experimentalist”: Gamow (1966), p.
213.
e
complete Faust text is translated here by Barbara Gamow.
605.
“e Neutron...
you agree?: ibid., p.
213.
606.
“at which...
heart in”: ibid., p.
214.
607.
“Now a...
along!”: ibid.
Chapter 7: Exodus
608.
“Antisemitism...
is violent”: Nathan and Norden (1960), p.
37
609.
“A new...
Newton”: Pais (1982), Plate II.
610.
Nobel Prize nominations: cf.
ibid., p.
502ff.
611.
“made...
beyond Newton”: quoted in ibid., p.
508.
612.
“a massive...
muscled”: Snow (1967a), p.
52.
613.
“A powerful...
slipped off”: ibid., p.
49.
614.
“to look...
his image”: Erikson, “Psychoanalytic Reflections on
Einstein’s Centenary,” p.
157, in Holton and Elkana (1982).
615.
“dressed in...
his eyes”: Infeld (1941), p.
92.
616.
“finally the...
structure”: quoted in Pais (1982), p.
239.
e paper is A.
Einstein, PAW (1915), p.
844.
617.
“One of...
scientific ideas”: quoted in Clark (1971), p.
290.
618.
popular lectures: cf.
Feuer (1982), p.
82.
619.
disrupted lecture: cf.
Pais (1982), p.
315ff.
620.
“said that...
German spirit”: quoted in Clark (1971), p.
318.
621.
Einstein mistakenly thought: cf.
Einstein to Arnold Sommerfeld,
Sept.
6, 1920: “I attached too much importance to that attack on me,
in that I believed that a great part of our physicists took part in it.
So
I really thought for two days that I would ‘desert’ as you call it.
But
soon there came reflection.” Quoted in ibid., p.
323ff.
622.
“ ‘My Answer...
disposition, then”: quoted in ibid., p.
319.
623.
“Everyone...
my article”: quoted in Pais (1982), p.
316.
624.
“miracle...
deeply hidden”: quoted in ibid., p.
37.
625.
“If you...
the things”: quoted in Clark (1971), p.
469.
626.
“rough the...
social environment”: quoted in ibid., p.
36.
627.
His father stumbled: for a careful reconstruction of this period in
Einstein’s life cf.
ibid., p.
39ff.
628.
“Politically...
my youth”: quoted in ibid., p.
315.
629.
medically unfit: Pais (1982), p.
45n.
630.
“victorious child”: Holton and Elkana (1982), p.
151.
631.
“I sometimes...
grown up”: quoted in Clark (1971), p.
27.
632.
E = mc 2: the paper is A.
Einstein, Jahrb.
Rad.
Elektr.
4, 411 (1907).
633.
“It is...
for radium”: quoted in Pais (1982), p.
149.
634.
“e line...
the nose”: revised from ibid., p.
148ff.
635.
“like men...
postage stamp”: quoted in Holton and Elkana (1982),
p.
326.
636.
“great work...
were slender”: quoted in Clark (1971), p.
252.
637.
“I begin...
younger years”: c.
1915, revised from Pais (1982), p.
243.
638.
“were...
ambivalent”: quoted in ibid., p.
315.
639.
“a new...
eternity”: quoted in Clark (1971), p.
473.
640.
“first discovered...
and dispersion”: quoted in ibid., p.
475.
641.
“undignified...
annoyed”: quoted in Pais (1982), p.
314.
642.
“in a...
anti-Semitism also”: quoted in Young-Bruehl (1982), p.
92.
643.
“I am...
in Germany”: quoted in Feuer (1982), p.
xxvi.
644.
54,000 marks: deJonge (1978), p.
240.
645.
“I was...
years ago”: Roberts (1938), p.
265.
646.
“ese points...
Wittenberg!”: quoted in Toland (1976), p.
96.
647.
refers to Jewry more frequently: cf.
Hitler (1971), index.
648.
“no lovers...
of decomposition”: ibid., passim.
649.
e sun shines in: cf.
photograph of Hitler’s cell in Toland (1976),
between pp.
172-173.
650.
lederhosen: cf.
photograph of Hitler at Landsberg, ibid.
651.
“I oen...
magic formula!”: quoted in ibid., p.
64.
652.
“If at...
in vain”: Hitler (1971), p.
679.
653.
e Jewish people: sources for this discussion include Arendt
(1973), Bauer (1982), Cohn (1967), Dawidowicz (1967, 1975),
Laqueur (1965), Litvinoff (1976), Mendelsohn (1970), Mendes-
Flohr and Reinharz (1980), Parkes (1964), Patai (1977), e
Protocols of the Meetings of the Learned Elders of Zion (1934),
Rosenberg (1970), Veblen (1919), Weizmann (1949).
654.
e fantasy of Jews: cf.
Cohn (1967), p.
254.
655.
“the enemies of Christ”: Parkes (1964) attributes this canard to
Catherine II in 1762.
e Encyclopedia Judaica, however, ascribes it
to the Czarina Elizabeth Petrovna in 1742.
Whether mother-or
daughter-in-law made the statement, it clearly reflects imperial
opinion of the Jews at the time of the Polish partition.
656.
Edward Teller’s grandmother: interview with Herbert York, La Jolla,
Calif., June 27, 1983.
657.
“e Jews...
a citizen”: Mendes-Flohr and Reinharz (1980), p.
104.
658.
“Jewish disorders”: quoted in Levin (1977), p.
18.
659.
Jews to the U.S.: for annual numbers cf.
Mendes-Flohr and Reinharz
(1980), p.
374.
660.
“I have...
of course”: reported by Herman Rauschning, quoted in
Cohn (1967), p.
60.
661.
“We owe...
by heart”: quoted in Arendt (1973), p.
360.
662.
“At eleven...
the accursed”: Cohn (1967), p.
34.
663.
“What I...
the goyim” : Protocols (1934), p.
142.
664.
“produced...
our slaves”: ibid., p.
175ff.
665.
“e principal...
the Papacy”: ibid., p.
193.
666.
“It will...
a merit”: ibid., p.
205.
667.
Protocols plagiarized: the best discussions of the bizarre history of
the Protocols are Cohn (1967) and Laqueur (1965).
668.
“gave them...
state itself”: Arendt (1973), p.
39.
669.
“us the...
larger scale”: ibid., p.
360.
670.
“Do you...
need them”: Richard Breitling was the journalist.
Quoted in Beyerchen (1977), p.
10.
671.
meeting with Goebbels: cf.
Goebbels’ diary entry quoted in
Dawidowicz (1975), p.
68.
672.
“I have...
couldn’t happen”: quoted in Blumberg and Owens
(1976), p.
51.
673.
“I didn’t...
to change”: Otto Frisch OHI, AIP, p.
12.
674.
“Civil...
must retire”: quoted in Dawidowicz (1975), p.
77.
675.
“descended from...
grandparents”: quoted in ibid., p.
78.
676.
a quarter of the physicists: Beyerchen (1977), p.
44.
677.
Some 1,600 scholars: ibid.
678.
“I decided...
my life”: quoted in Clark (1971), p.
539.
679.
“We sat...
to America”: quoted in ibid., p.
543.
680.
“Ich bin...
dafür”: quoted in ibid., p.
544.
681.
fieen thousand: according to Pais (1982), p.
450.
Clark (1971), p.
544, has $16,000.
682.
“Turn around...
again”: quoted in Pais (1982), p.
318.
683.
“recommended...
me also”: Eugene Wigner OHI, AIP, p.
2.
684.
“ere was...
it well”: ibid., p.
6.
685.
Leo Szilard to Eugene Wigner: Oct.
8, 1932, Egon Weiss personal
papers, USMA Library, West Point, N.Y.
Trans.
Edda König.
686.
“close...
1933”: Weart and Szilard (1978), p.
14.
687.
“On entering...
up here”: Elsasser (1978), p.
161.
688.
numbers of dismissals: Beyerchen (1977), p.
44.
689.
Bethe’s dismissal: cf.
Bernstein (1980), p.
34.
690.
“Geiger...
personal level”: ibid., p.
33.
691.
“He wrote...
nothing”: ibid., p.
35.
692.
Bethe at 27: telephone interview with Rose Bethe, Jan.
18, 1984.
693.
“I was...
whatever”: interview with Hans Bethe, Ithaca, N.Y., Sept.
12, 1982.
694.
“Sommerfeld...
come back”: Bernstein (1980), p.
35.
695.
“His early...
mechanics”: Wigner (1969), p.
2.
696.
“It was...
I could”: interview with Edward Teller, Stanford, Calif.,
June 19, 1982.
697.
“an old German nationalist”: quoted in Blumberg and Owens
(1976), p.
49.
698.
“I really...
in Germany”: ibid.
699.
“quite shocked...
the line”: Frisch (1979), p.
52.
700.
“very disappointed...
back to”: Otto Frisch OHI, AIP, p.
14.
701.
“To me...
I felt”: Rozental (1967), p.
137.
702.
“Stern...
Blackett had”: Frisch OHI, AIP, p.
14.
703.
“If physics...
dictator”: quoted in “Patrick Maynard Stuart
Blackett,” Biog.
Mem.
F.R.S.
21, p.
22.
704.
“Lise Meitner...
to you”: Frisch OHI, AIP, p.
12ff.
705.
Bohr persuaded him: so Franck told Alice Kimball Smith: Smith,
“e Politics of Control—e Role of the Chicago Scientists.”
Symposium on the 40th Anniversary of the First Chain Reaction,
University of Chicago, Dec.
2, 1982.
Franck’s daughters have
emphasized to the contrary that his decision to resign in protest was
made “for himself and by himself and nobody else had any part in
making it”: Beyerchen (1977), p.
16; p.
215, n.
8.
706.
Max Born’s reinstatement: according to Beyerchen (1977), p.
21.
707.
“We decided...
of May”: Born (1971), p.
113.
708.
“Ehrenfest...
young ones”: ibid., p.
113ff.
709.
“the old...
for it”: Shils (1964).
Shils tells the Vienna story here at length and notes that he heard it not from Szilard but from “other
persons.” It was, he writes, “absolutely characteristic of Szilard to
launch a campaign of aid and claim no credit later for himself.”
710.
“that as...
do something”: ibid., p.
38.
711.
the major U.S.
effort: cf.
Duggan and Drury (1948) and Weiner
(1969).
712.
“a long...
interview”: Weart and Szilard (1978), p.
32.
713.
“university of exiles”: Born (1971), p.
114.
714.
In Switzerland: Szilard reports these activities in a letter to
Beveridge dated May 23, 1933.
Leo Szilard Papers.
715.
“sympathetic...
German scientists”: Szilard to Beveridge, ibid.
716.
“he proposed...
them out”: Frisch (1979), p.
53.
717.
Benjamin Liebowitz: for biographical data cf.
“A memorial service
for BENJAMIN LIEBOWITZ,” Egon Weiss personal papers, West Point.
718.
“It is...
Germany”: Liebowitz to Ernest P.
Boas, May 5, 1933.
Szilard Papers.
719.
“dismissed...
stronger”: Weart and Szilard (1978), p.
36.
720.
“rather tired...
the parties”: ibid., p.
35.
721.
Locker-Lampson: cf.
Clark (1971), p.
566ff.
722.
“talking...
goats”: quoted in ibid., p.
603.
723.
“He did...
forward”: Moon (1974), p.
23.
724.
British appointments: Bentwich (1953), p.
13, puts this number at
155.
725.
American contributions: ibid., p.
19: “e total American financial
contribution by 1935 equalled that of the rest of the world.”
726.
Emergency Committee arrivals: cf.
Duggan and Drury (1948), p.
25.
727.
one hundred physicists: Weiner (1969), p.
217.
728.
“is a...
distraction”: Nathan and Norden (1960), p.
245.
729.
“fell in...
to him”: Wigner OHI, AIP, p.
5.
730.
“large and...
atmosphere”: Ulam (1976), p.
69ff.
731.
“I used...
the climate”: ibid., p.
158.
732.
“was astonished...
and sang”: Infeld (1941), p.
245.
733.
Hans Bethe walked: Hans Bethe OHI, AIP.
734.
“When I...
me away”: Mendelssohn (1973), p.
164.
Chapter 8: Stirring and Digging
735.
Stirring and Digging: cf.
Francis Bacon, e Advancement of
Learning: “Surely to alchemy this right is due, that it may be
compared to the husbandman whereof Aesop makes the fable: that,
when he died, told his sons that he had le unto them gold buried
underground in his vineyard; and they digged all over the ground,
and gold they found none; but by reason of their stirring and
digging the mould about the roots of their vines, they had a great
vintage the year following: so assuredly the search and stir to make
gold hath brought to light a great number of good and fruitful
inventions and experiments.” Quoted in Seaborg (1958), p.
xxi.
736.
the Gamows’ escape: cf.
Gamow (1970), p.
108ff.
737.
“I...
my eyes”: ibid., p.
120.
738.
“You see...
to arrange”: ibid., p.
122.
739.
“the voice...
they were!”: ibid., p.
123.
740.
“unable...
neutron”: quoted in Weart (1979), p.
44.
741.
“In the...
encouragement”: revised from ibid., p.
44, and Biquard
(1962), p.
36.
742.
“the emission...
element”: Joliot, quoted in Biquard (1962), p.
36.
743.
“I irradiate...
it continues”: quoted in ibid., p.
32.
744.
“e following...
working order”: ibid., p.
37.
745.
“e yield...
million atoms”: Joliot (1935), p.
370.
746.
“never...
of view”: quoted in Weart (1979), p.
46.
747.
“Marie Curie...
her life”: quoted in Biquard (1962), p.
33.
748.
“one of...
the century”: Segrè (1980), p.
197ff.
749.
“ese...
transmutation”: ibid., p.
198, where the letter to Nature is
reproduced as Fig.
9.15.
750.
“I congratulate...
any success”: quoted in Biquard (1962), p.
39.
751.
“we are...
necessary precautions”: Joliot (1935), p.
373.
752.
“spending much...
very long”: Weart and Szilard (1978), p.
36.
753.
“became...
chain reaction”: ibid., p.
17.
754.
“a little...
a job”: ibid.
755.
“I remember...
memoranda”: ibid., p.
19ff.
756.
a patent application: cf.
Szilard (1972), p.
622ff.
757.
March 12, 1934: LS completed the application on Saturday, March
10.
He had to wait until Monday to file.
758.
books on microfilm: cf.
Szilard (1972), p.
722.
759.
“In accordance...
substances”: ibid., p.
622.
e balance of the
application seems to concern a rough early conception of a
thermonuclear fusion reactor of the Shiva type with a blanket for
breeding heavy-element transmutations!
760.
“that the...
the other”: Weart and Szilard (1978), p.
18.
761.
“None of...
England”: ibid.
762.
Fermi was prepared: cf.
Holton (1974), for evidence and a
discussion.
763.
“I remember...
effective”: Frisch (1976b), p.
46.
764.
Both Fermi’s biographers: L.
Fermi (1954) and Segrè (1970).
765.
“Fermi must...
handwriting”: Segrè (1970), p.
8.
766.
“I studied...
physics”: quoted in ibid., p.
10.
767.
“a very...
death”: quoted in ibid., p.
11.
768.
“the partial...
examination”: ibid., p.
12.
769.
“In the...
propagandist”: Fermi to Enrico Persico, Jan.
30, 1920, in
ibid., p.
194.
Segrè translates the extant Fermi-Persico
correspondence in an appendix, p.
189ff.
770.
“shy...
solitude”: ibid., p.
33.
771.
“could not...
nebulous”: ibid., p.
23.
772.
“he...
in Rome”: ibid., p.
33.
773.
“Fermi remembered...
recognize him”: interview with Emilio
Segrè, Lafayette, Calif., June 29, 1983.
774.
“toward...
experiment”: Segrè (1970), p.
23.
775.
“disliked...
possible”: quoted in ibid., p.
55.
776.
“enlightening simplicity”: ibid.
777.
“quantum engineer”: quoted by Weisskopf in Weiner (1972), p.
188.
778.
“Not a...
pretty active”: quoted in Davis (1968), p.
266.
779.
“cold...
nature”: quoted in ibid., p.
265.
780.
“Fermi’s thumb...
flying”: L.
Fermi (1954), p.
7ff.
781.
“was...
sex appeal”: ibid., p.
10.
782.
“perhaps...
than against”: ibid., p.
15.
LF’s emphasis.
783.
the time was ripe: sources for this discussion include Holton (1974)
and Amaldi (1977) as well as L.
Fermi (1954) and Segrè (1970).
784.
“A fantastic...
intuition”: quoted in Holton (1974), p.
172.
785.
too remote: according to Segrè (1970), p.
72.
786.
Fermi found amusing: Segrè interview, June 29, 1983.
787.
Fermi skiing: L.
Fermi in Badash (1980), p.
89.
788.
“We had...
radioactivity”: quoted in Holton (1974), p.
173, n.
81.
789.
“Since the...
interesting”: Rabi (1970), p.
16.
790.
“e location...
of study”: Segrè (1970), p.
53.
791.
crude Geiger counters: cf.
Amaldi (1977), p.
301, Fig.
3, and Libby
(1979), p.
41.
792.
100,000 neutrons: cf.
Fermi paper (hereaer FP) 84 b, Fermi (1962),
p.
674.
793.
“Small cylindrical...
seconds”: ibid.
794.
“We organized...
our stuff”: Segrè (1955), p.
258ff.
795.
e next letter: FP 85 b, Fermi (1962), p.
676.
796.
“Amaldi...
good loser”: L.
Fermi (1954), p.
89.
797.
800 millicuries: cf.
FP 99, Fermi (1962), p.
748.
798.
“a very...
determined”: FP 86 b, ibid., p.
678.
799.
“is negative...
than 92”: FP 99, ibid., p.
750.
800.
“a new element”: cf.
partial text of Corbino’s address in Segrè (1970),
p.
76.
801.
“e discoveries...
wars”: Weart and Szilard (1978), p.
37.
802.
“Of course...
the point”: ibid., p.
39.
803.
“the liberation...
the chain”: Szilard (1972), p.
639.
804.
critical mass: cf.
ibid., p.
642.
805.
“some cheap...
an explosion”: ibid.
806.
“Marie Curie...
not corrupted”: quoted in Eve (1939), p.
388.
807.
“which was...
experiments”: Weart and Szilard (1978), p.
20.
808.
Szilard applied to Rutherford: cf.
LS to Ernest Rutherford, June 7,
1934, Szilard Papers.
809.
“ese experiments...
confirmed”: Weart and Szilard (1978), p.
20.
810.
the problem with helium: cf.
Brown (n.d.), p.
53ff.
811.
early in July: Amaldi (1977), p.
305.
216.
“going on...
laboratory”:
ibid.
812.
an unanswered question: cf.
Amaldi (1977), p.
310, and FP 98 (p.
744), FP 103 (p.
755) and p.
641 of Fermi (1962).
813.
“We also...
3 minutes”: Amaldi (1977), p.
310.
814.
radiative-capture problem: cf.
FP 103, Fermi (1962), p.
754ff.
815.
“and those...
important”: ibid., p.
756.
816.
“Shortly aerwards...
results”: ibid., p.
641.
817.
“In particular...
same room”: Amaldi (1977), p.
311ff.
818.
“I will...
have been”: quoted in Segrè (1970), p.
80.
e colleague
was Subrahmanyan Chandrasekhar.
819.
“About noon...
radioactivity”: ibid.
820.
“the halls...
magic!”: L.
Fermi (1954), p.
98.
821.
water worked: cf.
FP 105 b, Fermi (1962), p.
761ff.
822.
“Fermi dictated...
time”: Segrè (1970), p.
81.
823.
“ey shouted...
drunk”: L.
Fermi (1954), p.
100.
824.
“Influence of...
neutrons—I”: FP 105 b, Fermi (1962).
825.
“e case...
same element”: ibid., p.
761.
826.
“might never...
found out”: Hans Bethe OHI, AIP, p.
30.
827.
Physical Review paper: A.
von Grosse, Phys.
Rev.
46:241 (1934).
828.
“It was...
characteristics”: Hahn (1966), p.
141.
829.
“I began...
chamber”: Amaldi (1977), p.
317.
830.
“e experiments...
results”: ibid.
831.
“rough these...
weight 239”: FP 107, Fermi (1962), p.
791.
832.
“Other examples...
bromine”: Szilard (1972), p.
646.
833.
“So I...
a chemist”: Weart and Szilard (1978), p.
18.
834.
“understood...
done”: ibid., p.
19.
835.
Frederick Alexander Lindemann: cf.
especially Mendelssohn (1973),
p.
168ff.
836.
“If your...
physicist”: quoted in ibid., p.
168.
837.
“he became...
for arrogance”: ibid., p.
169.
838.
“unbending...
gentlemen”: ibid., p.
168.
839.
“gracious living...
friendship”: ibid., p.
171.
840.
“saw a...
modern war”: Churchill (1948), p.
79ff.
841.
“the question...
as possible”: Weart and Szilard (1978), p.
41.
842.
“there is...
taking patents”: ibid., p.
40.
843.
“Early in...
proper use”: ibid., p.
42.
844.
“from private...
at Oxford”: ibid.
845.
“there appears...
concerned”: quoted in ibid., p.
18, n.
28.
846.
“I daresay...
Government anything”: quoted in Szilard (1972), p.
733.
847.
“contains...
this country”: ibid., p.
734.
848.
“Bohr in...
that game”: Rozental (1967), p.
138.
849.
“e lid...
past year”: ibid., p.
153.
850.
“was drowned...
for him”: Oppenheimer (1963), II, p.
30.
851.
“On that...
understand it”: Frisch (1979), p.
102.
852.
“Neutron capture and nuclear constitution”: Bohr (1936).
853.
“For still...
to become”: ibid., p.
348.
854.
“the consequences...
developed”: ibid.
855.
“is 1937...
cleared up”: Wheeler (1963b), p.
40.
856.
Rutherford’s death: cf.
Eve (1939), p.
424ff, and Oliphant (1972), p.
153ff.
857.
“seedy”: quoted in Oliphant (1972), p.
154.
858.
“a wonderful...
of hope”: quoted in ibid., p.
155.
859.
“I want...
Nelson College”: quoted in Eve (1939), p.
425.
860.
“When the...
life”: Oliphant (1972), p.
155.
861.
“Life is...
encouragement”: Smith and Weiner (1980), p.
204.
862.
“to me...
father”: Bohr (1958), p.
73.
863.
“Voltaire...
atomic physics”: quoted in Eve (1939), p.
430ff.
864.
“I have...
attractive”: ibid., p.
424.
865.
“On element 93”: Zeitschri für Angewandte Chemie 47: 653.
Cf.
translation in Graetzer and Anderson (1971), p.
16ff.
866.
Segrè remembers: cf.
Emilio Segrè OHI, AIP, p.
24, and my Segrè
interview.
867.
“I think...
elements”: Otto Frisch OHI, AIP, p.
38.
868.
“It is...
element”: FP 98, Fermi (1962), p.
734.
869.
He later told Teller, Segrè, Woods: e.g., the three citations ff.
870.
“Fermi refused...
of nuclei”: Teller (1979), p.
140.
871.
“You know...
to himself”: Segrè interview, June 29, 1983.
872.
“Why was...
allowed”: Libby (1979), p.
43.
Chapter 9: An Extensive Burst
873.
“I believe...
been granted”: Meitner (1964), p.
2.
874.
“quite convinced...
had done”: James Chadwick OHI, AIP, p.
76.
875.
“Slight...
by nature”: Frisch (1968), p.
414.
876.
“there...
X-rays”: Frisch (1978), p.
427.
877.
“persuaded...
collaboration”: Meitner (1962), p.
6.
878.
“not only...
Professor Hahn”: Hahn (1966), p.
66.
879.
“she could...
story-teller”: Frisch (1968), p.
414.
880.
“totally...
vanity”: Frisch (1978), p.
426.
881.
“though...
could play”: Frisch (1968), p.
414.
882.
“It...
alert”: Axelsson (1946), p.
31.
883.
“the vision...
final truth”: Frisch (1978), p.
426.
884.
“For Hahn...
to explain”: ibid., p.
428.
885.
Hahn met Joliot: Weart (1979), p.
57.
886.
“It seems...
its interpretation”: quoted in Graetzer and Anderson
(1971), p.
37.
887.
“Who knows...
storm”: quoted in Churchill (1948), p.
262.
888.
“e years...
conditions”: Meitner (1959), p.
12.
889.
Meitner feared: cf.
Frisch (1968), p.
410ff.
890.
“I gave...
an emergency”: an important detail; aer the war Meitner bitterly accused Hahn of railroading her out of Germany so
that he would not have to share the discovery of fission with her—as
if he foresaw it in July.
Cf.
Hahn (1970), p.
199.
891.
“I took...
Holland colleagues”: Axelsson (1946), p.
31.
892.
Physical Institute: such is LM’s address in Meitner and Frisch
(1939).
In his postwar recollections Frisch consistently places her at
the “newlybuilt” Nobel Institute.
893.
she photographed him: cf.
Szilard (1972), p.
18.
894.
“He told...
the day”: quoted in Leigh Fenly, “e Agony of the
Bomb, and Ecstasy of Life with Leo Szilard.” San Diego Union, Nov.
19, 1978, p.
D-8.
895.
“a very...
a ‘stranger’ ”: LS to Gertrud Weiss, March 26, 1936.
Trans.
Edda König.
Szilard Papers.
896.
“stay in...
the war?”: Weart and Szilard (1978), p.
20ff.
897.
Lewis L.
Strauss: details of his life from Pfau (1984), which Dr.
Pfau
was kind enough to allow me to read in MS.
898.
“My boy...
you down”: quoted in ibid.
899.
“I became...
hospitals”: Strauss (1962), p.
163.
900.
the report to Nature: cf.
Szilard (1972), pp.
140, 147ff.
901.
“An isotope...
my parents”: Strauss (1962), p.
164.
902.
“August 30...
Leo Szilard”: Szilard Papers.
903.
owned patent jointly: “Patents which have been taken out by Dr.
Brasch and Dr.
Szilard were to be brought into this foundation.” File
memorandum, Szilard Papers.
904.
“asked me...
‘surge generator’ ”: Strauss (1962), p.
164.
905.
“In the...
fresh fruit”: Shils (1964), p.
39.
906.
debates among lawyers: cf.
file memorandum, Szilard Papers.
907.
“On April...
taste unchanged”: M.
Lenz to LS, April 15, 1938.
Szilard Papers.
908.
“I le...
wife here”: Emilio Segrè OHI, AIP, p.
31.
909.
a map of Ethiopia: Segrè (1970), p.
87.
910.
“He was...
to fascism”: ibid., p.
63.
911.
“We worked...
Civil War”: quoted in ibid., p.
90.
912.
“at was...
Italy”: ibid., p.
91.
913.
“America...
of Europe”: ibid., p.
92.
914.
“I have...
through anything”: quoted in Shirer (1960), p.
343.
915.
“Rome of...
and master”: revised from Segrè (1970), p.
95.
916.
Fermi told Segrè: ibid., p.
96.
917.
“Jews...
Italian race”: quoted in L.
Fermi (1954), p.
119.
918.
“Why should...
can’t he?”: quoted in Frisch (1979), p.
108.
919.
“the dangers...
other societies”: Bohr (1958), p.
23.
920.
“we may...
and variety”: ibid., p.
30.
921.
the German delegates: according to Moore (1966), p.
218.
922.
“the...
prejudices”: Bohr (1958), p.
31.
923.
“destroying...
each other”: Arendt (1951), p.
478.
924.
Bohr and Fermi’s Nobel: cf.
L.
Fermi (1954), p.
120ff.
925.
Goldhaber: cf.
Szilard (1972), p.
141ff.
926.
“the whole...
be delayed”: Churchill (1948), p.
292.
927.
“I just...
and see”: Weart and Szilard (1978), p.
21.
928.
“was...
mood”: quoted in Churchill (1948), p.
301.
929.
“e British...
worse treatment”: ibid., p.
301ff.
930.
“conditions...
security”: quoted in ibid., p.
302.
931.
“He told...
was accepted”: quoted in ibid., p.
306.
932.
“that this...
than Germans”: quoted in ibid., p.
309.
933.
“How horrible...
my soul”: quoted in ibid., p.
315.
934.
“regard the...
another again”: quoted in ibid., p.
318.
935.
invasion of British Isles: cf.
ibid.
936.
“is is...
our time”: quoted in ibid.
937.
Lindemann drove up: this story and Lindemann’s remark appear in
Mendelssohn (1973), p.
172.
938.
“the complete...
of force”: Churchill (1948), p.
303.
939.
HAVE ON...
DECISIONS: Weart and Szilard (1978), p.
48.
940.
“As my...
decreased”: Szilard (1972), p.
185.
941.
University of Rochester: Goldhaber, Hill and Szilard, Phys.
Rev.
55:47, refers to these experiments “to be reported in the following
paper.” ey are therefore not reported in Phys.
Rev.
55:47 as Weart
and Szilard (1978) assert (p.
53, n.l ).
Szilard in Weart and Szilard
(1978), p.
53, says to the point: “I went up to Rochester and stayed
there for two weeks and made some experiments on indium which
finally cleared up the mystery.” Since he wrote the Admiralty on
Dec.
21, 1938 (cf.
Weart and Szilard, p.
60), the Rochester work
probably occurred in late November-early December.
942.
“Taken...
by fractionation”: quoted in Graetzer and Anderson
(1971), p.
38.
943.
“You can...
muddled up”: quoted in ibid., p.
39ff.
944.
Strassmann speculated: cf.
Irving (1967), p.
21.
Irving interviewed
both Strassmann and Hahn.
945.
“must be...
alpha particles”: quoted in Graetzer and Anderson
(1971), p.
42.
946.
Meitner wrote in warning: according to Frisch (1979), p.
115.
Frisch
says elsewhere that this letter has been lost.
It is not included among
the Hahn-Meitner correspondence in Hahn (1975).
All translations
from the Hahn-Meitner correspondence by Edda König.
947.
“Bohr was...
elements”: Hahn (1970), p.
150.
948.
“Hard...
be withdrawn”: L.
Fermi (1954), p.
123.
949.
“especially rich ones”: quoted in Dawidowicz (1975), p.
135.
950.
“your discovery...
slow neutrons”: quoted in Segrè (1970), p.
98.
951.
“Most of...
very interesting”: Hahn (1975), p.
75ff.
952.
Meitner’s living conditions: cf.
ibid., pp.
91, 93, 103.
953.
Eva von Bahr-Bergius: Johansson (n.d.), p.
1, and Hahn (1975), p.
103.
954.
“Of course...
important apparatus”: Hahn (1975), p.
99.
955.
“Concerning...
care of”: ibid., p.
76.
956.
“a little...
somewhat better”: ibid., p.
77.
957.
“As much...
like barium”: ibid., p.
77ff.
958.
KWI layout: cf.
floor plan, Max Planck Society Library and Archive,
Berlin-Dahlem, and illustration accompanying “Die Kernspaltung,”
Bild der Wissenscha, Dec.
1978, pp.
68-69.
959.
KWI tables: the composite worktable preserved at the Deutsches
Museum in Munich would appear to be the measurement-room
table with a paraffin block, flasks and filters added to represent the
other work areas.
960.
“forms...
crystals”: Hahn (1966), p.
154ff.
961.
“e attempts...
being perceptible”: Hahn (1946), p.
58.
962.
“Exciting...
mesothorium”: quoted in Irving (1967), p.
23.
963.
“Perhaps you...
somewhat bearable”: Hahn (1975), p.
78ff.
964.
“very warm...
wishes”: ibid., p.
79.
965.
Hahn had little joy: cf.
ibid., p.
78: “How much I am looking forward
to it—aer such a long time without you—you can imagine.”
966.
Naturwissenschaen: cf.
ibid.: “But before the institute closes we still
want to write something...
for Natur-wiss.” (Dec.
19, 1938); p.
81:
“Since yesterday we have been putting together our Ra-Ba
proofs....
On Friday the work is supposed to be turned in to
Naturwiss....
e whole thing is not very well suited for [them] but
they will publish it quickly” (Dec.
21, 1938).
Cf.
also Irving (1967),
p.
27.
Irving has it nearly right.
967.
“Your radium...
impossible”: Hahn (1975), p.
79.
968.
“if you...
New Year”: ibid., p.
79ff.
969.
“Our radium...
it quickly”: ibid., p.
81.
970.
“Further experiments...
altogether”: Weart and Szilard (1978), p.
80.
971.
“just about...
point”: Szilard (1972), p.
185.
972.
Hahn’s and Strassmann’s paper: all quotations from Hahn and
Strassmann (1939a), trans.
Hans G.
Graetzer.
973.
“especially...
any more”: Hahn (1966), p.
157.
974.
“that I...
box”: Jungk (1958), p.
68.
e Rosebaud pickup version is
in Irving (1967), p.
27.
975.
Kungälv: for much of this history cf.
Claesson (1959).
976.
Frisch and Meitner in Kungälv: sources for this episode, one of the
most confused in the entire story, are Frisch (1967b, 1968, 1978,
1979); Frisch OHI, AIP; Rozental (1967); Clark (1980); Meitner
(1962, 1964).
A close reading of Hahn (1975) is extremely important
for straightening out the accumulated errors of memory.
977.
a quiet inn: the building, at No.
9, had become in 1982 a veterans’
hall.
978.
met in the evening: Frisch OHI, AIP, p.
33.
979.
a large magnet: ibid.
980.
insisted Frisch read it: Rozental (1967), p.
144: “But she wouldn’t
listen; I had to read that letter.”
981.
“Barium...
mistake”: Frisch OHI, AIP, p.
33.
982.
“Finally...
my problem”: Meitner (1962), p.
7.
983.
“But it’s...
that”: Frisch OHI, AIP, p.
34.
984.
“But how...
drop”: Rozental (1967), p.
144.
985.
“Couldn’t...
of thing”: Frisch OHI, AIP, p.
34.
986.
“Now...
opposite points”: ibid.
987.
“Well...
I mean”: ibid.
988.
“I remember...
instability”: ibid.
989.
“en...
energy”: ibid.
990.
“gave a...
well”: Meitner (1964), p.
4.
991.
“had...
her head”: Frisch OHI, AIP, p.
34.
992.
“One fih...
fitted”: Frisch (1979), p.
116.
993.
“Lise...
much lighter”: Frisch OHI, AIP, p.
37.
994.
Hahn’s letter of Dec.
21: cf.
LM to OH, Dec.
29, 1938: “Furthermore,
how about the so-called actinium?
Can they be separated from
lanthanum or not?” Hahn (1975), p.
83.
Hahn reported that result in
his Dec.
21 letter; if Meitner had received it she would have known.
995.
“barium fantasy...
something”: Hahn (1975), p.
82.
996.
“very exciting...
it”: ibid., p.
83.
997.
“Today...
amazing”: ibid.
998.
“against...
experience”: quoted in Weart (1979), p.
59.
999.
“We have...
start”: Hahn (1975), p.
84.
1000.
“If your...
results”: ibid.
1001.
“keen...
Bohr”: Rozental (1967), p.
145.
1002.
OF-NB meeting on Jan.
3: cf.
OF to LM, Jan.
13, 1939: “Only today
was I able to speak with Bohr about the bursting uranium.” Stuewer
(1985), p.
50.
1003.
“I had...
be!”: Rozental (1967), p.
145.
Frisch misplaces this
conversation to a later time.
1004.
“since Bohr...
tomorrow”: quoted in Stuewer (1985), p.
51.
1005.
“I am...
findings”: Hahn (1975), p.
85ff.
1006.
chronology of paper development and meeting with Bohr: Stuewer
(1985), p.
51, quoting a contemporary letter from OF to LM.
1007.
Frisch mentioned experiment to Bohr: cf.
Bohr’s letter to his wife
quoted at Moore (1966), p.
233: “I emphasized that Frisch had also
spoken of an experiment in his notes.” Note that according to OF
this discussion occurred before he talked to Placzek.
Placzek
probably did not, therefore, as OF later remembered, suggest the
experiment.
1008.
chronology of Placzek discussion: OF to LM, Jan.
8, 1939, quoted
in Stuewer (1985), p.
53.
1009.
“was like...
cancer”: Stuewer (1979), p.
72.
1010.
“One would...
high”: Frisch (1939), p.
276.
1011.
Jan.
13 until 6 A.M.: Frisch confirms date and time from his original
laboratory notes in Stuewer (1979), p.
72.
1012.
“pulses at...
two”: Frisch (1939), p.
276.
1013.
“At seven...
camp”: Frisch OHI, AIP, p.
35.
1014.
“a state...
confusion”: ibid.
1015.
William A.
Arnold: personal communication.
1016.
a dividing living cell: “Bohr had always urged that a nucleus
behaved like a small droplet; a uranium nucleus...
might divide
itself into two smaller nuclei...
much as a living cell becomes two
smaller cells by fission.” Frisch (1978), p.
428.
1017.
“I wrote...
tail”: Frisch OHI, AIP, p.
36.
1018.
two papers for Nature: Meitner and Frisch (1939); Frisch (1939).
1019.
papers posted: Stuewer (1985), p.
53.
1020.
“As we...
seasickness”: Rosenfeld (1979), p.
342.
1021.
“We...
Fermi family”: L.
Fermi (1954), p.
139.
1022.
“During the...
none”: ibid., p.
154.
1023.
Rosenfeld thought paper sent: cf.
Rosenfeld (1979), p.
343.
1024.
“In those...
train”: Stuewer (1979), p.
77.
1025.
“e effect...
directions”: Rosenfeld (1979), p.
343.
1026.
“I was...
off”: quoted in Moore (1966), p.
231.
1027.
Bohr letter to Nature: Bohr (1939a).
1028.
“Can you...
weeks”: Eugene Wigner OHI, AIP, p.
28.
1029.
“they said...
doomed”: interview with Eugene Wigner, Princeton
N.J., Jan.
21, 1983.
1030.
“Wigner told...
me”: Weart and Szilard (1978), p.
53.
1031.
“if, as...
proceeding”: quoted in Stuewer (1985), p.
52.
1032.
Rabi from Bohr himself: as he remembers it.
Telephone interview
Feb.
27, 1984.
1033.
“probably...
night”: telephone interview with Willis E.
Lamb, Jr.,
Feb.
24, 1984.
1034.
Rabi told Fermi: but remembers doing so as early as Jan.
17, 1939,
which is difficult to reconcile with Fermi’s proposal to Dunning of a
confirming experiment on Jan.
25.
1035.
“I remember...
news”: Fermi (1962), p.
996.
1036.
“spreading...
around”: Lamb interview, Feb.
24, 1984.
1037.
“e discovery...
uranium”: quoted in Segrè (1970), p.
217.
1038.
“I thought...
Fermi”: Weart and Szilard (1978), p.
53.
1039.
“I feel...
time”: ibid., p.
62.
1040.
Fermi/Dunning/Anderson experiment: cf.
Wilson (1975), p.
69ff,
and Sachs (1984), p.
18ff.
1041.
“He came...
say”: Wilson (1975), p.
69ff.
1042.
“Before I...
Bohr’s”: ibid., p.
71.
1043.
“All we...
thought”: ibid., p.
72.
1044.
“in general...
me”: quoted in Blumberg and Owens (1976), p.
70.
1045.
“Bohr has...
obvious”: Teller (1962), p.
8ff.
1046.
“Fermi...
at Princeton”: quoted in Moore (1966), p.
233.
1047.
Anderson returned to Pupin: cf.
Anderson’s account in Sachs
(1984), p.
24ff, which includes photostats of Anderson’s entries that
night in his laboratory notebook, quoted here.
1048.
thought Dunning would telegraph: Evidence that Dunning had not
wired Fermi as of Saturday night is Fermi’s unusual response to the
Roberts experiment at the DTM.
Cf.
Bolton (n.d.), p.
18.
Frisch’s
explanation to Bohr is quoted in Stuewer (1985), p.
53.
1049.
Bohr chiding Frisch: quoted in Stuewer (1985), p.
53.
1050.
“that no...
results”: quoted in ibid., p.
55.
1051.
51 participants: cf.
group portrait, Carnegie Institution archives,
Washington, D.C.
1052.
Gamow introduced Bohr: Roberts, et al.
(1939).
Roberts says Tuve
wrote the introductory paragraph to this contemporary paper; the
conference, it says, “began...
with a discussion by Professor Bohr
and Professor Fermi.” Cf.
also R.
B.
Roberts to E.
T.
Roberts, Jan.
30,
1939: “e annual theoretical physics conference started ursday
with an announcement by Bohr that Hahn in Germany had
discovered a radioactive isotope of barium as a product of
bombarding uranium with neutrons.” DTM archives, Carnegie
Institution.
1053.
“e eo...
implications”: Roberts (1979), p.
29.
1054.
“Fermi...
atomic power”: RBR to ETR, Jan.
30, 1939.
1055.
KINDLY...
WRITING: Weart and Szilard (1978), p.
60.
1056.
“in a...
anybody”: quoted in Weart (1979), p.
63.
1057.
Joliot’s response: cf.
ibid., p.
63ff.
1058.
APO: Dr.
Louis Brown, DTM, personal communication.
1059.
“Sat 4:30...
Kr?)”: R.
B.
Roberts laboratory notes (n.p.), DTM
archives.
1060.
“tremendous...
energy release”: RBR to ETR, Jan.
30, 1939.
1061.
“We promptly...
thorium”: Roberts (1979), p.
29.
1062.
“I told...
night”: RBR to ETR, Jan.
30, 1939.
1063.
all except Teller: RBR’s laboratory notes.
1064.
Fermi amazed: Bolton (n.d.), p.
18.
Bolton talked to both Roberts
and Meyer; both agreed on Fermi’s response.
1065.
“I had...
Nature”: quoted in Moore (1966), p.
236.
1066.
“ere...
phone calls”: Roberts (1979), p.
30.
1067.
“Fermi...
1939”: Wilson (1975), p.
73.
1068.
“I would...
physics”: ibid., p.
72.
1069.
“So...
almost pitiful”: Luis Alvarez OHI, AIP.
1070.
“About 9:30...
proceed”: Wilson (1975), p.
28ff.
1071.
“I remember...
conclusions”: Alvarez OHI, AIP.
1072.
“e U...
way”: Smith and Weiner (1980), p.
270ff, conjecture this
letter to have been written on Jan.
28, 1939.
e “papers” JRO refers
to must be Henry’s AP story, which reached Berkeley via the
Chronicle on Sunday, Jan.
29 (on the evidence of Abelson’s “About
9:30 a.m.”).
JRO dated the letter “Saturday”; probably therefore Feb.
4, 1939.
1073.
“might...
to hell”: Smith and Weiner (1980), p.
209.
1074.
“when fission...
bomb”: quoted in Weiner (1972), p.
90.
1075.
“A little...
disappear”: quoted in Kevles (1977), p.
324.
Chapter 10: Neutrons
1076.
I.
I.
Rabi: cf.
Bernstein (1975).
1077.
“infinite”: ibid., p.
64.
1078.
“the mystery...
nature is”: ibid., p.
50.
1079.
Szilard learned: cf.
Weart and Szilard (1978), p.
54.
1080.
“and say...
about it”: ibid.
1081.
“Nothing known...
quantitatively”: Wilson (1975), p.
76.
1082.
“From the...
precautions”: Weart and Szilard (1978), p.
54.
1083.
at Strauss’ request: Strauss (1962), p.
172.
1084.
“the performance...
been completed”: ibid., p.
171.
1085.
“No!...
on it”: Teller (1962), p.
9ff.
1086.
“It is...
than ever”: Rosenfeld (1979), p.
343.
1087.
“For example...
square foot”: quoted in Clark (1980), p.
86.
1088.
“From these...
slow neutrons”: Roberts et al.
(1939a), p.
417.
1089.
“Taking a...
blackboard”: Rosenfeld (1979), p.
343.
1090.
“He wrote...
the process”: ibid., p.
344.
1091.
“It was...
also present”: Dempster (1935), p.
765.
1092.
Nier measured the ratio: Nier (1939).
1093.
“changing from...
two MeV”: Fermi (1949), p.
166.
1094.
“Resonance in...
nuclear fission”: Bohr (1939b).
1095.
“were...
inseparable”: Fermi (1962), p.
999.
1096.
“slow neutrons...
in uranium”: Weart and Szilard (1978), p.
64.
1097.
“Bohr...
to U238”: Roberts et al.
(1940), second page of
introduction (unnumbered).
1098.
“For fast...
abundant isotope”: Bohr (1939b), p.
419.
1099.
a tank of water: cf.
Fermi (1962), p.
5ff.
1100.
“Szilard watched...
get them’ ”: Booth (1969), p.
11.
1101.
“All we...
no radium”: Weart and Szilard (1978), p.
55.
1102.
“to see...
uranium”: ibid., p.
64.
1103.
“just...
from England”: Weart and Szilard (1978), p.
55.
1104.
“a strange...
object”: Booth (1969), p.
11.
1105.
“Fermi and...
was U-238”: Booth (1969), p.
20.
1106.
“outraged”: quoted in Moore (1966), p.
248.
1107.
“It was...
Bohr’s argument”: Rosenfeld (1979), p.
345.
1108.
Roberts’ and Meyer’s Phys.
Rev.
letter: Roberts et al.
(1939b).
1109.
“As soon...
their thoughts”: Weart and Szilard (1978), p.
66.
1110.
Szilard-Zinn experiment: cf.
Szilard (1972), p.
158ff.
1111.
“Everything was...
went home”: Weart and Szilard (1978), p.
55.
1112.
“We find...
about two”: Szilard (1972), p.
158.
1113.
“more than...
absorbed”: Joliot et al.
(1939a), p.
471.
1114.
“a yield...
captured”: Fermi (1962), p.
6.
1115.
“I was...
the neutrons”: Teller (1962), p.
10.
1116.
PERFORMED...
50%: Strauss (1962), p.
174.
1117.
“at night...
for grief”: Weart and Szilard (1978), p.
55.
1118.
“strongly appealed...
discoveries”: LS to A.
H.
Compton, Nov.
12,
1942, p.
3.
MED 201.
1119.
“such a...
handling it”: Weart and Szilard (1978), p.
56.
1120.
G.
B.
Pegram: cf.
Embrey (1970).
1121.
“probably the...
world’s work”: quoted in ibid., p.
378.
1122.
“Experiments in...
be disregarded”: quoted in L.
Fermi (1954), p.
162.
1123.
“Szilard...
certainly possible?”: Stuewer (1979), p.
282.
1124.
“We tried...
into physics”: Teller (1979), p.
143.
1125.
“the enormous...
of U235”: Stuewer (1979), p.
282.
1126.
“it was...
taken seriously”: Fermi (1962), p.
999.
1127.
“it can...
huge factory”: Blumberg and Owens (1976), p.
89.
1128.
“two months...
one idea”: L.
Fermi (1954), p.
155.
1129.
“ere’s a wop”: Hans Bethe interview, Sept.
12, 1982.
1130.
“a...
board room”: Strauss (1962), p.
236.
1131.
officer taking notes: these details in ibid., p.
238.
1132.
“Enrico...
predictions”: L.
Fermi (1954), p.
165.
1133.
“to discuss...
the majority”: Weart and Szilard (1978), p.
56.
1134.
Joliot et al.
paper: Joliot et al.
(1939a).
1135.
“From that...
no sense”: Weart and Szilard (1978), p.
57.
1136.
a second Joliot paper: Joliot et al.
(1939b).
1137.
“e interest...
satisfied”: ibid.
1138.
“I began...
absurd”: quoted in Clark (1981), p.
58ff.
1139.
German initiatives: cf.
especially Irving (1967), the basic reference
to this subject.
1140.
“We take...
others”: quoted in ibid., p.
34.
1141.
“Tempers and...
atoms”: New York Times, April 30, 1939, p.
35.
1142.
“ere is...
whole matter”: quoted in Groueff(1967), p.
191.
1143.
“By separating...
very great”: Wilson (1975), p.
75.
1144.
“went back...
to do”: Booth (1969), p.
27.
1145.
“He was...
Fermi”: Wilson (1975), p.
76.
1146.
“e [radio]...
neutrons present”: Fermi (1962), p.
12.
1147.
“He liked...
time thinking”: Wilson (1975), p.
78.
1148.
“Szilard made...
assistant”: Emilio Segrè interview, June 29, 1983.
1149.
“very competent”: Wilson (1975), p.
78.
1150.
“about ten...
by uranium”: Fermi (1962), p.
12.
1151.
“an average...
perhaps 1.5 ”: ibid., p.
13.
1152.
“We were...
Placzek’s helium”: Weart and Szilard (1978), p.
81.
1153.
the resulting paper: Fermi (1962), p.
11ff.
1154.
“by an...
rays”: ibid., p.
15.
1155.
“I was...
to think”: Weart and Szilard (1978), p.
81.
1156.
“is an...
possibility”: ibid., p.
88.
1157.
“It seems...
reasonable price”: Szilard (1972), p.
195.
1158.
“ank you...
of uranium”: ibid., p.
197.
Fermi’s emphasis.
1159.
“the carbon...
canned form”: ibid., p.
196.
1160.
“even more...
considered”: ibid., p.
213.
1161.
“perhaps 50...
uranium”: ibid., p.
196.
1162.
about $35,000: LS to “Bill Richards,” July 9, 1939.
Szilard Papers.
1163.
“He took...
fall”: Weart and Szilard (1978), p.
82.
1164.
“I knew...
really seriously”: ibid.
1165.
“it seems...
no escape”: ibid., p.
90.
1166.
“Dr.
Wigner...
and me”: ibid., p.
98.
1167.
“He was...
concerned”: ibid., p.
82.
1168.
“shared the...
be advised”: Szilard (1972), p.
214.
1169.
“worry about...
to Germany?”: Weart and Szilard (1978), p.
82.
1170.
Gustav Stolper: LS implies in ibid., p.
84, that he first contacted
Stolper aer his first visit to Long Island.
His letter to Einstein of
July 19, 1939 (p.
90), however, makes it clear that he talked to
Stolper before his first visit but that Stolper did not connect him to
Alexander Sachs until aer that visit.
In 1945 (Hellman [1945], p.
70) Sachs implied that he had, been in touch with Einstein, Wigner
and Szilard before this introduction.
e contemporary record cited
here indicates otherwise.
1171.
Sunday, July 16: the letter that resulted from the first meeting was
transcribed by Wigner’s secretary on Monday morning; July 16,
1939, is the only Sunday between LS’s July 9 letter to Fermi and his
post-meeting July 19 letter to AE.
1172.
“We were...
us there”: Weart and Szilard (1978), p.
83.
1173.
“He came...
soda water”: Snow (1967), p.
52ff.
1174.
“Daran...
gedacht!”: Nathan and Norden (1960), p.
291; Clark
(1971), p.
669ff.
1175.
“very quick...
to object”: Weart and Szilard (1978), p.
83.
1176.
Einstein dictated a letter: cf.
ibid, for an English paraphrase of this
first Einstein dra.
e letter to Roosevelt that eventually resulted is
oen erroneously attributed to LS.
As will become apparent, that
letter grew directly from this first dra.
1177.
“He reported...
this matter”: ibid., p.
90.
1178.
Alexander Sachs: cf.
Hellman (1945).
Sachs’ book title appears on
the cover page of Notes on imminence world war in perspective
accrued errors and cultural crisis of the inter-war decades, March
10, 1939, MED 319.7.
1179.
“took the...
in person”: Weart and Szilard (1978), p.
91.
1180.
“Although I...
his promise”: ibid.
1181.
Teller midweek: cf.
LS to AE, July 19, 1939, ibid., p.
90.
1182.
“Perhaps you...
particularly nice”: Weart and Szilard (1978), p.
91.
1183.
July 30: I find no reference to this date except the garbled account in Blumberg and Owens (1976), p.
94, which gives it for the earlier
LS-Wigner visit.
It fell somewhere between July 20, 1939, when LS
called AE to confirm his proposal by letter of July 19, and August 2,
1939, when LS again wrote AE.
July 30 looks possible.
1184.
“I entered...
chauffeur”: NOVA (1980), p.
2.
1185.
a third text: cf.
LS to AE, July 2, 1939: “I am enclosing the German
text which we draed together in Peconic.” Weart and Szilard
(1978), p.
92.
1186.
“Yes, yes...
than indirectly”: quoted in Teller (1979), p.
144.
1187.
“at long...
middle man”: Weart and Szilard (1978), p.
92.
1188.
“that you...
too cleverly”: AE to LS (n.d.).
Szilard Papers.
Trans.
Edda König.
1189.
“We will...
too stupid”: Weart and Szilard (1978), p.
96.
Translation revised.
1190.
Lindbergh letter: cf.
ibid., p.
99.
1191.
“the Administration...
in America”: ibid., p.
95.
is is the letter
Sachs ultimately delivered to Roosevelt for AE.
Szilard’s
accompanying memorandum is in Szilard (1972), p.
201ff.
1192.
“If a...
the case”: Weart and Szilard (1978), p.
97ff.
1193.
“a horrible...
atomic bombings”: Wigner (1945), p.
28.
1194.
“the Hungarian conspiracy”: E.
P.
Wigner, memorandum to LS,
April 16, 1941.
Szilard Papers.
1195.
“Our social...
the eye”: U.S.
Senate (1945), p.
7.
1196.
“a perfect...
of armour”: Churchill (1948), p.
447.
1197.
“Adam and...
ever since”: Ulam (1976), p.
116.
1198.
revulsion against bombings: this discussion follows Hopkins
(1966).
1199.
“No theory...
people”: quoted in ibid., p.
454.
1200.
“inhuman...
populations”: quoted in ibid., p.
455.
1201.
“one of...
reprisals”: quoted in ibid., p.
457.
1202.
“Although...
to come”: ibid.
1203.
“e ruthless...
immediate reply”: Roosevelt (1939), p.
454.
1204.
a secret conference: cf.
Irving (1967), p.
40ff.
1205.
Bohr-Wheeler paper: Bohr and Wheeler (1939c).
1206.
“Preparatory...
Fission”: Irving (1967), p.
46n.
1207.
“felt that...
is abolished”: von Weizsäcker (1978), p.
199ff.
1208.
“is...
our man”: Weart and Szilard (1978), p.
100.
1209.
“He says...
matters stand”: ibid., p.
101.
1210.
late aernoon: on the evidence of the brandy and of Sachs’ evening
meeting with Briggs.
1211.
Watson meeting: according to AS to E.
Wigner, Oct.
17, 1939,
MED 319.7.
Hewlett and Anderson (1962) identify the two
participants besides Watson as Adamson and Hoover, the ordnance
specialists subsequently appointed to the Uranium Committee,
citing a 1947 statement filed by Adamson.
Sachs’ contemporary
letter is more authoritative.
1212.
“Alex...
up to?”: Moore (1966), p.
268.
I have found no other
source for this quotation or the Napoleon story but take it Moore
interviewed Sachs.
1213.
Napoleon story: ibid.
Moore places this story near the end of the
meeting, but it was clearly designed to catch FDR’s attention.
Cf.
also Hellman (1945), p.
71: “e October 11th White House
interview was one of a considerable series, during which Sachs,
according to friends, would ease the President into the discussion
with a few learned jokes.”
1214.
“Bah!...
visionists!”: A.
C.
Sutcliffe, Robert Fulton (Macmillan, 1915), p.
98.
1215.
“I am...
to him”: quoted in Hellman (1945), p.
70.
1216.
Sachs did not read the Einstein letter: there is considerable
evidence in the record to this point; cf.
especially Sachs’ almost-
explicit admission at U.S.
Senate (1945), p.
10: “e Einstein letter of
August 2, from which I quoted in part in my own letter, was le
with the President, along with my own letter.” Hewlett and
Anderson (1962), p.
17, confirm the omission: “Sachs read aloud his
covering letter, which emphasized the same ideas as the Einstein
communication but was more pointed on the need for funds.”
e scientific authority behind the meeting was nevertheless AE’s, as
FDR wrote AE on Oct.
19, 1939: “I found this data of such import
that I have convened a board...
to thoroughly investigate the
possibilities of your suggestion.” Nathan and Norden (1960), p.
297.
Some have questioned the effect of the Einstein/Szilard/Sachs contact.
Its effect was to convince FDR to appoint the Advisory Committee on
Uranium.
e emigrés were hardly to blame for the inadequacies of
that committee.
1217.
Sachs summation: Sachs (1945).
1218.
Sachs intentionally: U.S.
Senate (1945), p.
7.
1219.
“ambivalence...
and evil”: ibid., p.
9.
1220.
“the more...
door neighbor”: Aston (1938), p.
113ff.
Also quoted
in ibid.
1221.
“Alex...
requires action”: U.S.
Senate (1945), p.
9.
1222.
“Don’t let...
me again”: ibid.
1223.
Tuve deputized Roberts: Roberts (1979), p.
37.
1224.
Sachs breakfast: AS to E.
Wigner, Oct.
17, 1939.
MED 319.7.
1225.
Szilard began: cf.
his Oct.
26, 1939, memorandum to L.
Briggs
(Szilard [1972], p.
204ff), which embodies “the statements and
recommendations made by me at the meeting of October 21st”: LS
to LB, Oct.
26, 1939.
Weart and Szilard (1978), p.
110ff.
1226.
“too heavy...
airplane”: Szilard (1972), p.
202.
1227.
“In Aberdeen...
prize yet”: quoted in Teller (1979), p.
144.
1228.
ordnance depot: cf.
Blumberg and Owens (1976), p.
98.
1229.
Roberts raised objection: Sachs notes “a strong objection” (Sachs
[1945] p.
7) from “scientists who were not as much concerned as
these refugee scientists”—U.S.
Senate (1945), p.
11.
e only other
American scientist at the meeting besides Briggs was Möhler.
He
may have concurred with Roberts, but Roberts had the necessary
fast-neutron measurements.
1230.
“there are...
possibility”: Roberts (1939c), p.
613.
1231.
the DTM had begun assessing: Roberts writes: “Aer Florida [i.e.,
March 1939] I continued work...
on neutron scattering but my
main efforts went into measuring cross-section for fission for
neutrons of various energies.
ese were essential in calculating
whether a chain reaction would run.” Roberts (1979), p.
37.
Roberts
“made rough measurements of the fission cross-section for neutrons
in the energy range 500-2000 kv.” Roberts (1940), p.
2.
1232.
“very unlikely...
reaction”: Roberts (1939c), p.
613.
1233.
Briggs spoke up: Sachs (1945), p.
11.
1234.
“astonished...
enthusiastic”: Weart and Szilard (1978), p.
110.
1235.
“e issue...
ahead”: U.S.
Senate (1945), p.
11.
1236.
“I said...
is expensive”: Blumberg and Owens (1976), p.
98.
1237.
“How much...
need”: Eugene Wigner interview, Jan.
21, 1983.
1238.
“e diversion...
such recommendation”: Weart and Szilard
(1978), p.
110.
1239.
“For the...
me yet”: Teller (1979), p.
145.
1240.
$33,000: Szilard (1972), p.
205.
1241.
“At this...
be cut”: Weart and Szilard (1978), p.
85.
1242.
“All right...
your money”: Hewlett and Anderson (1962), p.
20.
1243.
Uranium Committee report: excerpts at Sachs (1945), p.
7ff.
1244.
Fermi letter: EF to AOCN, Oct.
28, 1939.
A.O.C.
Nier, personal
communication.
1245.
Nier finally began preparing: A.O.C.
Nier, personal
communication.
Chapter 11: Cross Sections
1246.
“I regularly...
every night”: Otto Frisch OHI, AIP, p.
12.
1247.
“in a...
any good”: ibid., p.
40.
1248.
“I first...
concentration camp”: ibid., p.
39ff.
1249.
“So I...
tourist”: Frisch (1979), p.
120.
1250.
“a great...
sobriety”: ibid., p.
121.
1251.
“a sample...
changed”: ibid., p.
123ff.
1252.
“material enriched...
bottom”: ibid., p.
124.
1253.
“the most...
Hitler war”: Snow (1981), p.
105.
1254.
“I managed...
on time”: Frisch (1979), p.
125.
1255.
“at process...
the trouble”: Frisch (1971), p.
22.
1256.
“new explosives...
by them”: Churchill (1948), p.
386ff.
1257.
when Oliphant consulted Peierls: cf.
Frisch (1971), p.
123.
1258.
Perrin’s formula: Perrin (1939).
1259.
Peierls’ formula: Peierls (1939).
1260.
“of the...
practical significance”: Clark (1981), p.
85.
1261.
“ran her...
times since”: Frisch (1979), p.
130.
1262.
“Is that...
written?”: Frisch OHI, AIP, p.
39.
1263.
“I wondered...
be needed?”: Frisch (1979), p.
126.
1264.
“we had...
to happen”: Frisch (1977), p.
23.
1265.
1023 cm2: ibid.
1266.
“Just...
playfully”: ibid., p.
22
1267.
“To my...
or two”: Frisch (1979), p.
126.
1268.
four millionths/second: Gowing (1964), p.
391.
1269.
“I worked...
by them”: quoted in Clark (1981), p.
88.
1270.
“I had...
be possible”: Frisch (1979), p.
126.
1271.
“e cost...
the war”: Wilson (1975), p.
55.
1272.
“Look...
about that?”: Frisch OHI, AIP, p.
39.
1273.
“ey...
me”: Oliphant (1982), p.
17.
1274.
“I remember...
were doing”: Frisch (1977), p.
25.
1275.
“On the...
in uranium”: the full text appears at Gowing (1964), p.
389ff.
1276.
“to point...
discussions”: ibid., p.
389.
1277.
“the energy...
or less”: ibid., p.
391.
1278.
“Memorandum...
‘super-bomb’ ”: Ronald M.
Clark found this
document among the papers of Henry Tizard and published it in
Clark (1965), p.
214ff.
1279.
“I have...
present time”: quoted in ibid., p.
218.
1280.
“I have...
on it”: Frisch (1979), p.
126.
1281.
“heavy water...
yet known”: Irving (1967), p.
49.
1282.
Norsk Hydro: cf.
ibid., pp.
49ff, 56ff.
1283.
Allier and heavy water: cf.
Weart (1979), p.
130ff.
1284.
“e complete...
United States”: York (1976), p.
30.
For York on
Soviet research cf.
p.
29ff.
1285.
Japanese studies: cf.
Pacific War Research Society (1972) (hereaer
PWRS) and Shapley (1978).
1286.
Takeo Yasuda: PWRS (1972), p.
18ff.
1287.
“We are...
any day”: quoted in Moore (1966), p.
267.
1288.
“this...
coup”: Churchill (1948), p.
600.
1289.
“It was...
to persecute”: Rozental (1967), p.
160ff.
1290.
Nobel Prize medals: cf.
de Hevesy (1962), p.
27.
1291.
1.5 tons heavy water: Irving (1967), p.
61.
1292.
“What I...
a committee”: quoted in Clark (1965), p.
218.
1293.
“the possibility...
the Germans”: quoted in Clark (1981), p.
92ff.
1294.
“We entered...
be investigated”: Gowing (1964), p.
394.
1295.
“unnecessarily excited”: quoted in Clark (1981), p.
94.
1296.
“I still...
very low”: quoted in Clark (1965), p.
219.
1297.
“Dr.
Frisch...
was feasible”: quoted in Clark (1981), p.
95.
1298.
“e Committee...
separation”: Oli-phant (1982), p.
17.
1299.
“the most...
was wrong”: Weart and Szilard (1978), p.
115.
1300.
Watson decided: Hewlett and Anderson (1962), p.
21.
1301.
“a crucial...
application”: quoted in ibid.
1302.
“Divergent chain...
and carbon”: Szilard (1972), p.
216ff.
1303.
“seemed to...
went home”: Weart and Szilard (1978), p.
115.
1304.
“the most...
this research”: ibid., p.
122.
1305.
“I worked...
of uranium”: Booth et al.
(1969), p.
28.
1306.
“very doubtful...
uranium”: quoted in Hewlett and Anderson
(1962), p.
20.
1307.
“ese experiments...
in uranium”: Nier et al.
(1940a).
1308.
“Furthermore...
unseparated U”: Nier et al.
(1940b).
1309.
400 to 500 × 10−24 cm2: Nier et al.
(1940a).
1310.
“Cartons of...
make measurements”: Wilson (1975), p.
83ff.
Anderson recalls 1.5 tons of graphite here; but Fermi (1962), FP 136,
p.
34, the report of this experiment, confirms the larger figure.
1311.
“So physicists...
happening”: Fermi (1962), p.
1000.
1312.
“A precise...
delight him”: Wilson (1975), p.
84.
1313.
3 × 10~27 cm2: Fermi (1962), p.
32.
1314.
“scientists...
Institution”: Gowing (1964), p.
43.
1315.
“It is...
goose chase”: quoted in Clark (1965), p.
220.
1316.
Teller calculation: Hewlett and Anderson (1962), p.
32.
1317.
“the cross-section...
pure uranium”: Roberts et al.
(1940),
Introduction, second page.
1318.
“I came...
miracle happened”: Teller (1977), p.
11.
1319.
“To deflect...
my mind”: Blumberg and Owens (1976), p.
100.
1320.
“In the...
to go”: Teller (1979), p.
145.
1321.
Teller had never bothered: cf.
ibid.
1322.
“We had...
to me”: quoted in Forbes, Feb.
18, 1980, p.
62.
1323.
“the continuance...
mystic immunity”: Roosevelt (1941), p.
184.
1324.
“en he...
be lost”: Teller (1979), p.
145ff.
1325.
“but something...
be lost”: Blumberg and Owens (1976), p.
101.
1326.
“conquest and...
different cause”: Roosevelt (1941), pp.
184-187.
1327.
“My mind...
changed since”: Blumberg and Owens (1976), p.
101.
1328.
“at experience...
lack meant”: Bush (1970), p.
74.
1329.
“It was...
certainly need”: ibid., p.
33.
1330.
“something meshed...
language”: ibid., p.
35.
1331.
“Each of...
to turn”: ibid., p.
36.
1332.
“the threat...
our minds”: ibid., p.
34.
1333.
Bush and Conant proving impossibility: this insightful assessment
comes from Dupree (1972), p.
456.
1334.
“I remember...
and voice”: Snow (1967b), p.
149ff.
1335.
Franz Simon: cf.
Arms (1966).
1336.
“use my...
this country”: ibid., p.
111.
1337.
Simon joked: ibid., p.
109.
1338.
“It was...
the streets”: quoted in Clark (1981), p.
108.
1339.
“Within a...
the matter”: Moon (1977), p.
544.
1340.
“I do...
taken seriously”: quoted in Gowing (1964), p.
47.
1341.
hammered kitchen strainer: Arms (1966), p.
109, says this
occurred in “late spring.” Fitted against other events June is a
reasonable surmise.
1342.
“Arms...
separate isotopes”: ibid.
1343.
“e first...
soda-water”: quoted in Clark (1981), p.
110.
1344.
MET...
KENT: quoted in ibid., p.
95.
1345.
“an anagram...
they can”: quoted in ibid., p.
96.
1346.
strategic bombing: cf.
Burns (1967); Kennett (1982); Saundby
(1961).
1347.
“short...
air raid”: quoted in Kennett (1982), p.
112.
1348.
“to undertake...
are available”: quoted in ibid., p.
113.
1349.
Hitler reserved London: ibid., p.
118.
1350.
“And if...
cities out!”: quoted in ibid., p.
119.
1351.
“will-to-resist”: quoted in ibid., p.
118.
1352.
“a systematic...
Lion unnecessary”: quoted in ibid., p.
120.
1353.
HE tonnage: Harrisson (1976), p.
128.
1354.
deaths: ibid., p.
265.
1355.
Simon report: reproduced, probably in rewritten form, under a
different title as part of the MAUD Report and given in this form in
Gowing (1964), p.
416ff.
I quote from the MAUD version, p.
416.
1356.
Simon delivered report: Arms (1966), p.
111.
1357.
Auer ordered sixty tons: Irving (1967), p.
65.
1358.
Joliot: the cyclotron episode appears at Weart (1979), p.
156ff.
1359.
Bothe graphite measurements: Bothe (1944).
1360.
“When...
was on”: Weart and Szilard (1978), p.
116.
1361.
“ese galling...
scientific fraud”: Bothe (1951), p.
Iff.
Trans.
Louis Brown.
1362.
“uranium...
not work”: Frisch (1979), p.
138.
1363.
“only for...
consideration”: Irving (1967), p.
80.
Irving’s report of
Harteck’s meaning is here and on p.
277; the heavy-water
recommendation is also here.
1364.
Suzuki report/Nishina: PWRS (1972), p.
19ff; Shapley (1978), p.
153.
1365.
Turner letter to Phys.
Rev.: Turner (1946).
1366.
“It seems...
to say”: Weart and Szilard (1978), p.
126ff.
1367.
Turner review article: Turner (1940).
1368.
“a little...
of isotopes”: Weart and Szilard (1978), p.
126.
1369.
“it is...
be used”: Turner (1946).
1370.
“In 94 EkaOs240...
be expected”: Turner (1946).
1371.
Bohr had speculated: cf.
Nobel Committee presentation speech
preceding McMillan (1951), p.
310ff.
1372.
“When a...
a book”: McMillan (1951), p.
314.
1373.
“Nothing very...
very interesting”: ibid., p.
315.
1374.
“a uranium...
neutron capture”: McMillan (1939).
1375.
“the two-day...
explanation”: McMillan (1951), p.
316.
1376.
“Segrè...
the story”: ibid., p.
317.
1377.
“As time...
vacation”: ibid., p.
318.
1378.
“When he...
work together”: ibid., p.
319.
1379.
“Within a...
like uranium”: Wilson (1975), p.
33.
1380.
“Radioactive element 93”: McMillan and Abelson (1940).
1381.
“it might...
contribution”: Weart and Szilard (1978), p.
127.
1382.
idea occurred to von Weizsäcker: cf.
Irving (1967), p.
68.
1383.
“finding that...
neptunium”: McMillan (1951), p.
321.
1384.
“I le...
national defense”: ibid., p.
322.
1385.
“excellent public...
children have”: L.
Fermi (1954), p.
145.
1386.
“an...
annual”: ibid., p.
148.
1387.
“ ‘D’you know...
crab grass”: quoted in ibid., p.
147.
1388.
“purposely studied...
Americanization”: Segrè (1970), p.
104.
1389.
Segrè at Purdue: Segrè discusses this episode, including Lawrence’s
attitude, in Emilio Segrè OHI, AIP, p.
33.
1390.
“the machine...
I do”: ibid.
1391.
“we had...
scary problem”: Segrè (1981), p.
11.
1392.
“Fermi...
94]”: ibid.
1393.
“I suggested...
his collaborators”: Seaborg (1976), p.
5.
1394.
Two searches: both of which may be followed day by day in ibid.
1395.
0.6 microgram: ibid., p.
13.
1396.
“key step...
discovery”: Seaborg (1958), p.
4.
1397.
Seaborg remembers: cf.
Bickel (1980), p.
188.
1398.
“With this...
94”: Seaborg (1976), p.
25.
1399.
“is morning...
neutrons”: ibid., p.
34.
1400.
larger critical mass: Gowing (1964), p.
68.
1401.
“is first...
is manageable”: quoted in ibid., p.
67ff.
1402.
“I remember...
28 years”: James Chadwick OHI, AIP, p.
105.
Chapter Twelve: A Communication from Britain
1403.
Conant: cf.
Conant (1970), Kistiakowsky and Westheimer (1979).
1404.
“the most...
race”: Conant (1970), p.
252.
1405.
“What shall...
formality”: quoted in ibid., p.
253.
1406.
“I said...
the Interior”: ibid., p.
52.
1407.
“I did...
or weapon”: ibid., p.
49.
1408.
“Conant achieved...
chemistry”: Kistiakowsky and Westheimer
(1979), p.
212.
1409.
“strong belief...
involving Briggs”: Conant (1970), p.
276ff.
1410.
“Light a...
possibilities?”: quoted in Childs (1968), p.
311.
1411.
Compton follow-up letter: K.
Compton to V.
Bush, March 17,
1941.
OSRD S-l, Bush-Conant File, folder 19.
1412.
“by nature...
solution”: ibid.
1413.
“I told...
trail behind”: VB to F.
Jewett, June 7, 1941.
Bush-Conant
File, f.
4.
1414.
“a very...
atomic weapon”: Wilson (1975), p.
205.
1415.
Bainbridge contacted Briggs: on the evidence of V.
Bush to F.
Jewett, April 15, 1941: “e immediate reason being a suggestion
from Bainbridge that we send a member of our group to London on
the uranium problem.” Bush-Conant File, f.
19.
1416.
“I am...
my head”: Bush (1970), p.
60.
1417.
“it would...
present time”: VB to FJ, April 15, 1941.
1418.
“It was...
scientific problems”: Compton (1956), p.
45.
1419.
“disturbed...
bloodedly evaluate”: VB to FJ, April 15, 1941.
1420.
“fitness...
task”: Compton (1956), p.
46.
1421.
“Arthur Compton...
and strong”: Libby (1979), p.
91ff.
1422.
“tallness...
enormously”: ibid., p.
16.
1423.
“a small...
place”: Compton (1967), p.
31.
1424.
“probably the...
of physics”: quoted in Pais (1982), p.
414.
1425.
“Bohr spoke...
different manner’ ”: Nielson (1963), p.
27.
1426.
“In 1940...
time later”: Compton (1967), p.
44.
1427.
“ere followed...
interested”: Compton (1956), p.
46.
1428.
first NAS report (May 17, 1941): Bush-Conant File, f.
3.
1429.
“the matter...
applications multiply”: ibid.
1430.
“And only...
negative”: Conant (1970), p.
278.
1431.
“authoritative and impressive”: discussed in FJ to VB, June 6, 1941.
Bush-Conant File, f.
4.
1432.
“a lurking...
well balanced”: ibid.
1433.
“is uranium...
doubt”: VB to FJ, June 7, 1941.
Bush-Conant
File, f.
4.
1434.
“We told...
at Columbia”: Seaborg (1976), p.
42.
1435.
“to crush...
against England”: Hitler directive #21, “Operation
Barbarossa,” Dec.
18, 1940, quoted in Churchill (1949), p.
589.
1436.
“What worried...
to priorities”: Conant (1970), p.
278ff.
Conant
(1943), p.
5, confirms this recollection.
1437.
Briggs learned from Lawrence: a letter dated July 10, 1941,
according to Conant (1943), p.
13.
1438.
“In the...
no money”: Eugene T.
Booth, personal communication.
1439.
“e government’s...
war program”: Compton (1956), p.
49.
1440.
“More significant...
entirely feasible”: Conant (1970), p.
280.
1441.
eight of twenty-four physicists: Conant (1943), p.
20.
1442.
“In essence...
‘dra report’ ”: ibid.
1443.
MAUD Report: given in full in Gowing (1946), p.
394ff.
1444.
“With the...
in order”: Conant (1943), p.
21.
1445.
“During July...
uranium program”: Conant (1970), p.
279.
1446.
“If each...
efficiently”: Weart and Szilard (1978), p.
138.
1447.
“Fritz Houtermans...
brilliant ideas”: Frisch (1979), p.
71ff.
1448.
“that at...
energy”: Bethe (1967), p.
216.
1449.
“but fell...
the Nazis”: Frisch (1979), p.
72ff.
1450.
Houtermans report: cf.
Irving (1967), p.
84.
1451.
“Every neutron...
thermal neutrons”: quoted in ibid., p.
85.
1452.
“at worst...
been defeated”: quoted in Clark (1981), p.
126.
1453.
“Although personally...
Lord Cherwell”: Churchill (1950), p.
814.
1454.
“If Congress...
receive one”: Weart and Szilard (1978), p.
146.
1455.
“most important...
and determined”: Conant (1943), p.
19.
1456.
“e minutes...
and distressed”: Oliphant (1982), p.
17.
1457.
“came to...
for submarines”: quoted in Davis (1968), p.
112.
1458.
“I’ll even...
in Berkeley”: quoted in Childs (1968), p.
315.
Childs
attributes this wire to Lawrence.
Since he was in Berkeley and
Oliphant in Washington, I take it to be Oliphant’s.
1459.
“How much...
complete consideration”: quoted in ibid., p.
316ff.
1460.
Oliphant sees Conant and Bush: cf.
Bickel (1980), p.
166.
Bickel
interviewed Oliphant at length.
1461.
“gossip...
subjects”: Conant (1943), p.
19.
1462.
“non-committal...
of fission”: quoted in Gowing (1964), p.
84n.
1463.
“that the...
serious consideration”: quoted in Conant (1943), p.
20.
1464.
“Certain developments...
its development”: Compton (1956), p.
6.
1465.
“out of the blue”: interview with Edward Teller, Stanford, Calif.,
June 19, 1982.
1466.
“I decided...
bombs”: Blumberg and Owens (1976), p.
110.
1467.
“Next Sunday...
believed me”: NOVA (1980), p.
3.
1468.
Hagiwara lecture: quoted in “Concerning uranium, Tonizo
Laboratory, April 43.” Document copy and translation in the private
collection of P.
Wayne Reagan, Kansas City, Mo.
1469.
Chicago meeting: Conant lists Pegram as a fourth participant.
Compton, who believed the meeting to be crucial to his future and
who describes it in detail, does not.
1470.
“It was...
talk freely”: Compton (1956), p.
7.
1471.
“very vigorous...
whole field”: Conant (1943), p.
21.
1472.
“Conant was...
be convinced”: Compton (1956), p.
7ff.
1473.
“I could...
research programs”: Conant (1970), p.
280.
1474.
“If this...
do it”: Compton (1956), p.
8.
1475.
“the results...
been exposed”: Conant (1943), p.
22.
1476.
“I grew...
a Russian’ ”: interview with George Kistiakowsky,
Cambridge, Mass., Jan.
15, 1982.
1477.
“When I...
have reservations?”: Conant (1970), p.
279.
1478.
“counted...
significant”: ibid., p.
280.
1479.
Bush memorandum: VB to J.
B.
Conant, Oct.
9, 1941.
Bush-
Conant File, f.
4.
Quotations describing Bush’s meeting with FDR
come from this memo.
1480.
“emphasized to...
are over”: VB to F.
Jewett, Nov.
4, 1941.
Bush-
Conant File, f.
4.
1481.
Bush to expedite research: cf.
VB to FDR, March 9, 1942: “In
accordance with your instructions [on October 9] I have since
expedited this work in every way possible.” Bush-Conant File, f.
13.
1482.
“called...
hundred pounds”: Compton (1956), p.
53ff.
1483.
Dunning and Booth choosing gaseous diffusion: Booth et al.
(1975), p.
Iff.
1484.
“Our...
enriched uranium”: Eugene T.
Booth, personal
communication.
1485.
barrier materials: cf.
Cohen et al.
(1983), p.
636ff.
1486.
“One cannot...
more tons”: FP 143, Fermi (1962), p.
99.
Herbert
Anderson’s headnote here confirms the chronology of this incident.
1487.
“He urged...
so well”: Compton (1956), p.
55.
1488.
October 21 in Schenectady: Compton (1956), p.
56, says
Cambridge, but Hewlett and Anderson (1962), p.
46, referring to the
minutes of the meeting, locate it here.
1489.
“I have...
deliberation”: quoted in Childs (1968), p.
321.
1490.
Conant scolded Lawrence: ibid., p.
319.
1491.
“lewandering activities”: quoted in ibid.
1492.
“Many of...
of them”: USAEC (1954), p.
11.
1493.
“causes and...
with us”: quoted in Childs (1968), p.
319.
1494.
Oppenheimer debated Lawrence: cf.
ibid.
1495.
“It was...
direct use”: USAEC (1954), p.
11.
1496.
“I...
forget it”: Smith and Weiner (1980), p.
220.
1497.
“Kistiakowsky...
members objected”: Compton (1956), p.
56ff.
1498.
“In our...
grave responsibility”: quoted in Childs (1968), p.
321.
1499.
“the destructiveness...
of inertia”: Compton (1956), p.
57.
1500.
“No help...
helpful suggestions”: ibid., p.
58.
1501.
“It was...
atomic bomb”: quoted in Irving (1967), p.
93.
1502.
“he was...
his trip”: E.
Heisenberg (1984), p.
77ff.
1503.
“with...
hospitality”: ibid., p.
78.
1504.
“Being aware...
this conversation”: quoted in Jungk (1958), p.
103ff.
1505.
“e impression...
actual events”: Rozental (1967), p.
193.
1506.
“Heisenberg and...
a standoff”: Oppenheimer (1963), III, p.
7.
1507.
Heisenberg reactor drawing: reported by Hans Bethe in Bernstein
(1979), p.
77.
1508.
“Bohr...
all else”: E.
Heisenberg (1984), p.
81.
1509.
“bond to...
Bohr’s reply”: ibid., p.
80.
1510.
“a state...
despair”: ibid., p.
81.
1511.
“he had...
enough spoon”: Mott and Peierls (1977), p.
230.
1512.
third NAS report: Report to the President of the National Academy
of Sciences by the Academy Committee on Uranium, Nov.
6, 1941.
Bush-Conant File, f.
18.
1513.
“e special...
with U235”: ibid., p.
1.
1514.
“a fission...
can be”: ibid.
1515.
“e mass...
fast neutrons”: ibid., p.
2.
1516.
“may be...
itself”: ibid., p.
3.
1517.
“approaching...
test”: ibid., p.
4.
1518.
“in...
four years”: ibid.
1519.
“e possibility...
this program”: ibid., p.
6.
1520.
“more...
of accomplishment”: Compton (1956), p.
61.
1521.
“leaving Briggs...
Ernest Lawrence”: VB to FJ, Nov.
4, 1941.
Bush-Conant File, f.
4.
1522.
“Jan 19...
FDR”: Bush-Conant File, f.
13.
1523.
“e meeting...
more firmly”: Compton (1956), p.
70.
1524.
“a worthy...
said Conant”: ibid., p.70ff.
1525.
“the construction...
secret project”: Conant (1970), p.
282.
1526.
December 7, 1941: I rely primarily on Prange (1982) for this
summary reconstruction, but cf.
also Murukami (1982), Coffey
(1970) and Toland (1970).
1527.
“must be...
ever seen”: quoted in Prange (1982), p.
500.
1528.
“Negotiations with...
disclose intent”: quoted in ibid., p.
402.
1529.
“a defense...
Philippines”: quoted in ibid., p.
403.
1530.
“is dispatch...
tasks assigned”: quoted in ibid., p.
406.
1531.
“more...
phrasing”: quoted in ibid., p.
409.
1532.
“Well...
it”: quoted in ibid., p.
501.
1533.
Nagasaki torpedoes: cf.
ibid., p.
323.
Chapter 13: The New World
1534.
“Szilard at...
customers”: Fermi (1962), p.
1003.
1535.
thirty tons of graphite: ibid., p.
546.
1536.
“Much of...
with heap”: Segrè (1970), p.
116.
1537.
“We...
oxide”: Fermi (1962), p.
1002.
1538.
e cans: cf.
FP 150, ibid., p.
128.
1539.
“is structure...
as possible”: ibid.
1540.
“We were...
exhausting work”: Wilson (1975), p.
86.
1541.
“We...
four pounds”: Fermi (1962), p.
1002.
1542.
“Fermi tried...
and precision”: Wilson (1975), p.
87.
1543.
k: cf.
FP 149, Fermi (1962), p.
120.
1544.
“Now that...
Pearl Harbor”: ibid., p.
1002ff.
1545.
“the atmosphere...
optimism reigned”: Conant (1943), II, p.
2.
1546.
the next day: i.e., Dec.
19, 1941.
Compton gives Dec.
20 but cf.
Hewlett and Anderson (1962), p.
53.
1547.
“On the...
18 months”: AHC to VB et al., Dec.
20, 1941, p.
2.
Bush-Conant File, folder 5.
1548.
“is figure...
per year”: Compton (1956), p.
72.
1549.
Anderson scouting locations: cf.
his letter to Szilard, Jan.
21, 1942,
Szilard Papers.
1550.
“egg-boiling”: ibid.
1551.
“Each was...
for Chicago”: Compton (1956), p.
80.
1552.
“We will...
war”: quoted in Compton, “Operation of the
Metallurgical Project,” memorandum, July 28, 1944.
Bush-Conant
File, f.
20a.
1553.
“Finally, wearied...
to Chicago”: Compton (1956), p.
81.
1554.
“had come...
moving again”: L.
Fermi (1954), p.
174.
1555.
“was unhappy...
quite efficiently”: ibid., p.
169.
1556.
THANK YOU...
ORGANIZATION: AHC to LS, Jan.
25, 1942.
Szilard
Papers.
1557.
uranium press: Libby (1979), p.
70.
Libby’s chronology here is
garbled, however.
1558.
“ere are...
ordered one”: L.
Fermi (1954), p.
186.
LF believed
the pile was canned to exclude the air, but cf.
FP 151, Fermi (1962),
p.
137: “Particular care was taken to eliminate as much as possible
the moisture.”
1559.
“required soldering...
the job”: Wattenberg (1982), p.
23.
1560.
“To insure...
their heads”: L.
Fermi (1954), p.
186.
1561.
“Like the...
winter meant”: Churchill (1950), p.
536.
1562.
“well-fed...
fighting”: Guderian, quoted in Shirer (1960), p.
862.
1563.
“e winter...
certain”: Churchill (1950), p.
537.
1564.
“e work...
near future”: quoted in Irving (1967), p.
94.
1565.
“Experimental Luncheon”: cf.
Goudsmit (1947), p.
170.
1566.
“too busy...
moment”: quoted in ibid., p.
171.
1567.
“Pure uranium-235...
colossal force”: quoted in Irving (1967), p.
99.
1568.
“it would...
to detonate”: quoted in ibid., p.
100.
1569.
“e first...
be done”: quoted in Groves (1962), p.
335.
Note that this is testimony obtained surreptitiously by bugging while its
subjects, who have claimed it was mistranslated and misinterpreted,
were prisoners of war.
To the extent that it is reliable it is far more
candid than published statements, however.
1570.
“In the...
its importance”: Speer (1970), p.
225.
1571.
“e word...
reaction”: quoted in Irving (1967), p.
108.
1572.
“As...
a pineapple”: quoted in ibid., p.
109.
1573.
“His answer...
the war”: Speer (1970), p.
226.
1574.
“Hitler had...
see it”: ibid., p.
227.
1575.
“on the...
propelling machinery”: ibid.
1576.
“In the...
prime movers”: Heisenberg (1947), p.
214.
1577.
“We may...
finding out”: VB to FDR, March 9, 1942.
Bush-
Conant File, f.
13.
1578.
March 9 report: “Report to the President, status of tubealloy
development” (n.d.).
Bush-Conant File, f.
13.
1579.
“I think...
the essence”: FDR to VB, March 11, 1942.
Bush-
Conant File, f.
13.
1580.
“While all...
the other”: JBC to VB, May 14, 1942.
Bush-Conant
File, f.
5.
1581.
Conant reviewed the evidence: cf.
ibid.
1582.
“if the...
of machinery”: ibid.
1583.
Seaborg to Chicago: chronology and details of this section follow
Seaborg (1977).
1584.
“is day...
Project”: ibid., p.
2.
1585.
250 ppm: Seaborg (1958), p.
16.
1586.
“We conceived...
were employed”: ibid., p.
8.
1587.
“I...
precipitation”: Seaborg (1977), p.
9.
1588.
“Sometimes I...
right now”: ibid., p.
42.
1589.
“We looked...
concrete bench”: ibid., p.
56.
1590.
“I always...
fit”: ibid., p.
112.
1591.
“It was...
balance”: Seaborg (1958), p.
38.
1592.
“the fellows...
Hall”: Seaborg (1977), p.
66.
1593.
“But to...
the north”: ibid., p.
68.
1594.
“Our witnesses...
stay”: ibid., p.
70.
1595.
“it was...
call”: ibid., p.
75.
1596.
“I do...
a whole”: G.
Breit to L.
Briggs, May 18, 1942.
Bush-
Conant File, f.
5.
1597.
“a prerequisite...
bomb”: Seaborg (1977), p.
75.
1598.
“because...
use helium”: ibid., p.
91.
1599.
“a water...
time”: Weart and Szilard (1978), p.
157.
1600.
“Compton repeated...
of 1944”: Seaborg (1977), p.
86ff.
1601.
“Compton opened...
people present”: ibid., p.
93ff.
1602.
“Stated in...
lines”: Weart and Szilard (1978), p.
156.
1603.
“In 1939...
were eliminated”: ibid., p.
152.
1604.
“e UNH...
a minimum”: Seaborg (1977), p.
148.
1605.
“facetiously...
attention”: interview with Glenn Seaborg, Berkeley,
Calif., June 22, 1982.
1606.
“Perhaps today...
of man”: Seaborg (1977), p.
192ff.
1607.
“a holiday...
hue”: ibid., p.
193.
1608.
“luminaries”: Smith and Weiner (1980), p.
227.
1609.
“I considered...
practical way”: quoted in Bernstein (1980), p.
70.
1610.
“Aer the...
effort”: quoted in ibid., p.
61.
1611.
“e essential...
hands full”: Smith and Weiner (1980), p.
226.
1612.
Kiddygram: cf.
ibid.
1613.
“our best...
country”: quoted in Bernstein (1980), p.
55.
1614.
early July: on July 9, 1942, Teller told Seaborg he was leaving for a
month in Berkeley.
Seaborg (1977), p.
111.
1615.
“He had...
probably work”: quoted in Bernstein (1980), p.
71.
1616.
“We were...
do it”: Teller (1962), p.
38.
1617.
“We had...
hydrogen bomb”: quoted in Bernstein (1980), p.
72ff.
1618.
“in the...
been tragic”: “Remarks by Raymond T.
Birge,” May 5,
1964, p.
5ff.
JRO Papers, Box 248.
1619.
“e theory...
do much”: interview with Hans Bethe, Ithaca, N.Y.,
Sept.
12, 1982.
1620.
“My wife...
doing it”: quoted in Bernstein (1980), p.
73.
1621.
35,000 eV/400 million degrees: Hawkins (1947), p.
14.
1622.
85,000 tons: ibid., p.
15.
1623.
500 atomic bombs: based on Bush’s March estimate of 2 KT per
“unit.”
1624.
“I didn’t...
know more”: Bethe interview, Sept.
12, 1982.
1625.
“I’ll never...
their calculations”: Compton (1956), p.
127ff.
1626.
“I very...
my arguments”: Bethe interview, Sept.
12, 1982.
1627.
“It was...
common sense”: Hawkins (1947), p.
15.
1628.
“My theories...
conclusion”: Teller (1962), p.
39.
1629.
“Konopinski...
guess”: ibid.
1630.
lithium deuteride: cf.
Teller to Oppenheimer, Sept.
5, 1942, JRO
Papers, Box 71: “In connection with these reactions it occurred to
me that our Lithium Deuterite estimate which we made at Berkeley
might be wrong...
But even so I agree that Lithium Hydride will
probably not be possible without some change in isotopic
composition.”
1631.
“We were...
unforgettable”: Bethe (1968), p.
398.
1632.
a major effort: cf.
Hawkins (1947), p.
2.
1633.
“Fast neutron...
work”: Seaborg (1977), pp.
269-271.
1634.
Cincinnati/Tennessee: ibid.
1635.
Conant notes: handwritten on yellow legal pad paper, headed
“August 26, 1942.
Status of the Bomb.” Bush-Conant File, f.
14a.
1636.
Executive Committee report: “Status of Atomic Fission Project,”
(n.d.), Bush-Conant File, f.
12.
1637.
“the physicists...
report”: via Harvey Bundy.
Cf.
VB,
“Memorandum for Mr.
Bundy,” July 29, 1942.
OSRD S-l Bush
Report March 1942 #58.
1638.
“Classical engineers...
everyone”: Libby (1979), p.
90ff.
1639.
Wilson’s meeting: Leona (Woods) Libby’s is the more detailed
recollection and squares with the timing of the Stone & Webster
appointment in June, following which the engineering firm
conducted preliminary studies during the summer.
Compton
apparently confuses the meeting Wilson called with the June
meeting Seaborg describes when the decision to turn Pu production
over to industry was first announced—also a rowdy meeting.
Cf.
Libby (1979), p.
90ff; Compton (1956), p.
108ff; Seaborg (1977), p.
93ff.
1640.
“We (some...
& Webster”: Libby (1979), p.
91.
1641.
“When Compton...
and disbanded”: ibid., p.
91 ff.
1642.
Szilard memorandum: Weart and Szilard (1978), p.
153ff, and dra
“Memorandum” dated Sept.
19, 1942, Szilard Papers.
1643.
“In talking...
instrument”: LS, dra “Memorandum,” p.
5.
1644.
“I have...
OSRD”: ibid., p.
4.
1645.
“e situation...
our work”: Weart and Szilard (1978), p.
155.
1646.
“ere is...
be functional”: ibid., p.
156.
1647.
“If we...
it up”: quoted in ibid., p.
147.
1648.
“We may...
responsibility lies”: ibid., p.
159ff.
1649.
“From my...
war efforts”: VB to Harvey Bundy, Aug.
29, 1942.
OSRD S-l Bush Report March 1942 #58, p.
4.
1650.
“On the...
Oh”: Groves (1948), p.
15.
1651.
“to take...
project”: “Memorandum for the Chief of Engineers,”
Sept.
17, 1942.
MD I/I/f.25b.
1652.
“I thought...
colonel”: Groves (1962), p.
5.
1653.
Groves’ father: cf.
Groves (n.d.), “e Army As I Saw It.”
1654.
“Entering West...
I knew”: ibid., p.
103.
1655.
“A...
wolf”: quoted in Davis (1968), p.
244.
1656.
“the biggest...
of understanding”: quoted in Goodchild (1980), p.
56ff.
1657.
“I was...
horrified”: Groves (1962), p.
19.
1658.
“I told...
the soup”: quoted in ibid., p.
20.
1659.
“His reaction...
his wishes”: ibid., p.
22.
1660.
“We had...
a year”: ibid., p.
23.
1661.
“You made...
start moving”: quoted in Groueff(1967), p.
15n.
Groueff interviewed Groves at length.
1662.
k = 0.995 : Hewlett and Anderson (1962), p.
70.
1663.
“I remember...
beach”: L.
Fermi (1954), p.
191.
1664.
“in frigid...
promontory”: Libby (1979), p.
2.
1665.
“One evening...
little kids”: ibid., p.
4.
1666.
“As he...
he was”: ibid., p.
1.
1667.
“I was...
we wanted”: R.
Sachs (1984), p.
33.
1668.
“At each...
‘metallurgists’ ”: L.
Fermi (1954), p.
176.
1669.
“one of...
his wife”: Compton (1956), p.
207.
1670.
“close to 1.04 ”: Fermi (1962), p.
207.
1671.
“For the...
questions asked”: Wilson (1975), p.
91.
1672.
1 percent improvement in k: Fermi (1962), p.
212.
1673.
Zinn preparations: cf.
FP 181 ibid.; Wattenberg (1982); Wilson
(1975), p.
108ff.
1674.
“e War...
build both”: Seaborg (177), p.
284ff.
1675.
“I le...
be impossible”: Groves (1962), p.
41.
1676.
“Its reasons...
design data”: ibid., p.
48.
1677.
“if we...
casualties”: ibid., p.
49.
1678.
“dreadful decision”: Seaborg (1977), p.
343.
1679.
“We did...
be intolerable”: Compton (1956), p.
137.
1680.
“most significant...
fission occurs”: ibid., p.
136ff.
1681.
delayed neutrons: Roberts et al.
(1939b).
1682.
“e only...
myself”: Compton (1956), p.
138.
1683.
building CP-1: cf.
Allardice and Trapnell (1955); Compton (1956),
p.
132ff; FP 181, Fermi (1962); L.
Fermi (1954), p.
176ff; Groueff
(1967), p.
54ff; Libby (1979), p.
118ff and passim; R.
Sachs (1984),
pp.
32ff and 281ff; Seaborg (1977), p.
388ff; Segrè (1970), p.
120ff;
Wigner (1967), p.
228ff; Wilson (1975), pp.
91ff and 108ff.
1684.
“Gus Knuth...
on hand”: Wilson (1975), p.
92.
1685.
number of layers: 57 layers/17 days/2 shis = 1.7 per shi.
1686.
“A simple...
and myself”: Wilson (1975), p.
93.
1687.
“Each day...
following shis”: Fermi (1962), p.
268.
1688.
pile countdown: these numbers charted in ibid., FP 181, p.
275.
1689.
“We tried...
the business”: quoted in Wilson (1975), p.
94.
1690.
“at night...
in place”: Fermi (1962), p.
269.
1691.
“I will...
leisurely”: ibid., p.
270.
1692.
“e next...
the batter”: Libby (1979), p.
120.
1693.
“Back we...
received heat”: ibid.
1694.
“several of...
the material”: Wattenberg (1982), p.
30.
1695.
“Fermi instructed...
supposed to”: ibid., p.
31.
1696.
“Again the...
control rod”: ibid.
1697.
“Aer the...
and locked”: ibid.
1698.
“is time...
level off”: quoted in ibid., p.
32.
1699.
“at first...
about it”: Wilson (1975), p.
95.
1700.
Fermi told tech council: cf.
Seaborg (1977), p.
394.
Seaborg gives k
= 1.006 , presumably a typographical error; cf.
FP 181, Fermi (1962),
p.
276.
1701.
“en everyone...
ZIP in!”: Wilson (1975), p.
95.
1702.
“Nothing very...
cannot foresee”: Wigner (1967), p.
240.
1703.
“We each...
except Wigner”: Wattenberg (1982), p.
32.
1704.
“bursting...
news”: Seaborg (1977), p.
390.
1705.
“in my...
University”: Conant (1970), p.
290.
1706.
“Jim...
and happy”: Compton (1956), p.
144.
1707.
“ere was...
of mankind”: Weart and Szilard (1978), p.
146.
Chapter 14: Physics and Desert Country
1708.
“massive...
work”: Bethe (1968), p.
396.
1709.
“[Oppenheimer]...
choir boy”: Chevalier (1965), p.
11.
1710.
“He was...
loved him”: Dorothy McKibben, quoted in Else (1980),
p.
9.
1711.
“He was...
unspoken wishes”: Chevalier (1965), p.
21.
1712.
“painful but...
my voice”: quoted in Davis (1968), p.
129.
1713.
“sometimes appeared...
most sensitive”: Segrè (1970), p.
134.
1714.
“Robert could...
like it”: quoted in Davis (1968), p.
103.
1715.
“But it...
or something”: Smith and Weiner (1980), p.
135.
1716.
“the loneliest...
world”: quoted in ibid., p.
145.
1717.
“My friends...
to change”: USAEC (1954), p.
8.
1718.
“I had...
my students”: ibid.
1719.
“very grave...
those days”: interview with Philip Morrison,
Cambridge, Mass., Jan.
1982.
1720.
“And through...
the community”: USAEC (1954), p.
8.
1721.
“In the...
and country”: ibid.
1722.
“I never...
to me”: ibid., p.
10.
1723.
“Dr.
[Stewart]...
it was”: ibid.
1724.
“I went...
the world”: ibid., p.
9.
1725.
“created the...
nuclear physics”: Bethe (1968), p.
396.
1726.
“He began...
to try”: quoted in Davis (1968), p.
79.
1727.
JRO meeting Groves: cf.
LRG to JRO, Sept.
27, 1960.
JRO Papers,
Box 36.
1728.
“I became...
no consideration”: USAEC (1954), p.
12.
1729.
“a military...
as officers”: ibid.
1730.
“original...
in Berkeley”: LLG to JRO, Sept.
27, 1960.
1731.
“the work...
pace”: Groves (1962), p.
60.
1732.
“Outside the...
Oppenheimer”: ibid., p.
62.
1733.
“It was...
a theorist”: Bethe (1968), p.
399.
1734.
“snag...
any means”: Groves (1962), p.
63.
1735.
“He’s a...
about sports”: interview, March 8, 1946.
Szilard Papers.
1736.
“Aer much...
the task”: Groves (1962), p.
62ff.
1737.
“by default...
bad name”: quoted in Davis (1968), p.
159.
1738.
“it was...
astonished”: Else (1980), p.
11.
1739.
October 15 and 19: cf.
LLG to JRO, Sept.
27, 1960.
1740.
“For this...
hands on”: Smith and Weiner (1980), p.
231.
1741.
Bethe, Segrè et al.: Kunetka (1982), p.
48.
1742.
“so that...
conditions”: Groves (1962), p.
64.
1743.
Groves’ criteria: cf.
Badash (1980), p.
3ff.
1744.
“a delightful...
Utah”: ibid., p.
4.
1745.
“a lovely...
satisfactory”: Smith and Weiner (1980), p.
236.
1746.
“considerable...
usable site”: Badash (1980), p.
14ff.
1747.
“as though...
directly there”: ibid., p.
5.
1748.
“e school...
its stream”: Church (1960), p.
4.
1749.
“beautiful...
country”: Segrè (1970), p.
135.
1750.
“hot and...
or moisture”: L.
Fermi (1954), p.
204.
1751.
“I remember...
the place’ ”: Badash (1980), p.
15.
1752.
“My two...
be combined”: quoted in Royal (1969), p.
49; cf.
also
Brode (1960), first page of Introduction.
I merge these two versions
of JRO’s statement; the sense is the same and the exact remark is
variously attested.
1753.
“Nobody could...
go crazy”: quoted in Davis (1968), p.
163.
1754.
Corps of Engineers’ appraisal: MED 319.1.
1755.
“What we...
accelerators”: Badash (1980), p.
30.
1756.
“e prospect...
Los Alamos”: USAEC (1954), p.
12ff.
1757.
“Oppenheimer...
radar”: Moyers (1984).
1758.
“the culmination...
physics”: quoted by JRO in Smith and Weiner
(1980), p.
250.
1759.
“To me...
consequence”: ibid.
1760.
“Laboratory...
our hi-jinks”: ibid., p.
243ff.
1761.
“Oppenheimer’s...
a teletype”: Badash (1980), p.
10.
1762.
“a very...
to come”: ET to JRO, March 6, 1943.
JRO Papers, Box
71.
1763.
Teller’s prospectus: referred to in ET to JRO, Jan.
4, 1943 (misdated
1942).
JRO Papers, Box 71.
1764.
“mental love...
in conversation”: quoted in Coughlan (1963), p.
90.
1765.
“fundamentally...
somewhat introverted”: quoted in Blumberg
and Owens (1976), p.
77.
1766.
Alvarez disagrees: personal communication.
1767.
“scientific autonomy...
our work”: Smith and Weiner (1980), p.
247ff.
1768.
“Several of...
camps”: L.
Fermi (1954), p.
201.
1769.
Vemork raid: cf.
Haukelid (1954); Irving (1967); Jones (1967).
1770.
“one of...
be repeated”: Jones (1967), p.
1422.
1771.
“Here lay...
Europe”: Haukelid (1954), p.
71.
1772.
“one of...
mountains”: ibid., p.
73.
1773.
“Halfway down...
and rivers”: ibid., p.
92ff.
1774.
“It was...
of sentries”: ibid., p.
94.
1775.
“We were...
grenades”: ibid., p.
95.
1776.
“the thin...
Europe”: ibid.
1777.
“but an...
to do?”: ibid., p.
98.
1778.
“the best...
seen”: quoted in Irving (1967), p.
149.
1779.
Japan: cf.
Pacific War Research Society (1972).
p.
27ff, and Shapley
(1978).
1780.
“e study...
field”: quoted in PWRS (1972), p.
26.
1781.
“e best...
the meeting”: ibid., p.
35.
1782.
“is was...
Engineers”: Badash (1980), p.
31.
1783.
“about thirty persons”: Segrè (1970), p.
135.
1784.
Los Alamos Primer: Condon (1943).
Designated LA-1.
1785.
“e object...
nuclear fission”: ibid., p.
1.
1786.
“Since only...
active material”: ibid., p.
2.
1787.
7 percent U235: Condon says at least tenfold; 1/140th × 10 = 7%.
Condon (1943), p.
5.
1788.
“to make...
possible”: ibid.
1789.
“the gadget”: ibid., p.
7.
1790.
“severe...
effects”: ibid., p.
9.
1791.
“Since...
is possible”: ibid., p.
10.
1792.
“e reaction...
gadget”: ibid., p.
11.
1793.
“as the...
[core]”: ibid., p.
13.
1794.
“An explosion...
distance”: ibid., p.
16.
1795.
“When the...
break”: ibid., p.
18.
1796.
“is...
at present”: ibid., p.
21.
1797.
illustration: Condon’s drawing, ibid.
1798.
“e highest...
10 tons”: ibid.
1799.
“If explosive...
sphere”: ibid., p.
22.
1800.
illustration: Condon’s drawing, ibid.
1801.
“All autocatalytic...
needed”: ibid., p.
24.
1802.
“relatively...
physics”: Hans Bethe OHI, AIP, p.
59.
1803.
“If there...
ceremony”: Badash (1980), p.
31ff.
1804.
April conference plans: cf.
Hawkins (1947), p.
16ff.
1805.
Neddermeyer’s thoughts: as reported to Davis (1968), p.
170ff.
1806.
“I remember...
implosion”: quoted in ibid., p.
171.
1807.
“expands...
sixteenfold”: Condon (1943), p.
15.
1808.
“At this...
hand”: quoted in Davis (1968), p.
171.
1809.
“e gun...
better still”: quoted in ibid., p.
172.
1810.
“At a...
of assembly”: Hawkins (1947), p.
23.
1811.
“Neddermeyer...
and Bethe”: quoted in Davis (1968), p.
173.
1812.
“Nobody...
seriously”: Badash (1980).
p.
34.
1813.
“is will...
into”: quoted in Davis (1968), p.
173.
1814.
“Aer he...
surprised”: quoted in ibid., p.
182.
1815.
Condon and e Tempest: cf.
Smith and Weiner (1980), p.
252.
1816.
the bombing of Hamburg: cf.
Kennett (1982), Middlebrook (1980),
Overy (1980).
1817.
“But when...
way through”: quoted in Jones (1966), p.
80ff.
1818.
“the targets...
bombing”: quoted in Kennett (1982), p.
128.
1819.
“that although...
night bombing”: Churchill (1950), p.
279.
1820.
Headlines proclaiming raids: for a discussion of this point cf.
Hopkins (1966), p.
461ff.
1821.
“It has...
workers”: quoted in Kennett (1982), p.
129.
1822.
“a bomber...
endure”: quoted in ibid., p.
130.
1823.
“INFORMATION...
HAMBURG”: quoted in Middlebrook (1980), p.
95.
1824.
Operation Gomorrah: I rely here on Middlebrook (1980).
1825.
“It was...
night”: quoted in ibid., p.
253.
1826.
“Most of...
them all”: quoted in ibid., p.
244.
1827.
“e burning...
like again”: quoted in ibid.
1828.
“en a...
of fire”: quoted in ibid., p.
259.
1829.
“Mother wrapped...
the doorway”: quoted in ibid., p.
264.
1830.
“We came...
knees screaming”: quoted in ibid., p.
266ff.
1831.
“Four-storey...
the pavement”: quoted in ibid., p.
276.
1832.
two million Soviet soldiers: Elliot (1972), p.
48.
Elliot puts total
Soviet military POWs at 5 million and POW deaths at 3 million; I
use his number here of those enclosed in occupied Russia, of which
he writes: “Total deprivation of entire enclosed populations...
does
not exist elsewhere in human history.” e other 3 million were
treated with more customary brutality.
1833.
mammalian reflex: cf.
Kruuk (1972).
1834.
“We must...
we’ve got”: quoted in Hopkins (1966), p.
464.
1835.
Lewis committee findings: cf.
Hawkins (1947), p.
24.
1836.
“In this...
for U235”: ibid., p.
71.
1837.
“I guess...
why?”: interview with Glenn Seaborg, Berkeley, Calif.,
June 22, 1982.
1838.
“en I...
suitcase”: ibid.
1839.
“Of course not”: Groves (1962), p.
160.
1840.
“all his...
the Navy”: Joseph Hirschfelder, quoted in Badash
(1980), p.
82.
1841.
“within a...
the job”: Groves (1962), p.
160.
1842.
Tuve reassignment: cf.
V.
Bush to MT, Aug.
14, 1941.
Bush-Conant
File, f.
4.
1843.
“As a...
externally”: Ramsey (1946), p.
6ff.
1844.
B-29: cf.
Birdsall (1980).
e first service-test model flew June 27,
1943 (ibid., p.
18).
1845.
“On August...
subsequent tests”: Ramsey (1946), p.
7.
1846.
“At that...
gun method”: Badash (1980), p.
17.
1847.
“ose tests...
practical method”: ibid.
1848.
“It stinks”: quoted in Davis (1968), p.
216.
1849.
“With everyone...
the beer”: quoted in ibid.
1850.
“a simple...
sophisticated”: quoted in ibid., p.
217.
1851.
“Johnny was...
previously discussed”: quoted in Blumberg and
Owens (1976), p.
455.
1852.
JvN and ET to JRO: the official record says “autumn.” I conjecture
October because the governing board met Oct.
28, 1943.
Hawkins
(1947), p.
76.
1853.
“In order...
1943”: Ramsey (1946), p.
8ff.
1854.
“Professor Bohr...
micro-slide”: Rozental (1967), p.
192 plate.
1855.
“e letter...
help”: ibid., p.
193ff.
1856.
“if I...
refuge here”: quoted in ibid., p.
194.
1857.
3.6 million Germans: Yahil (1969), p.
118.
1858.
“Danish statesmen...
government”: ibid., p.
200ff.
1859.
Margrethe Bohr remembers: cf.
Moore (1966), p.
302.
1860.
“We had...
small bag”: quoted in ibid., p.
303.
1861.
Bohr appeals to Swedish government: Flender (1963), p.
76.
Flender interviewed Bohr at length; his account is garbled, however.
1862.
284 people: Yahil (1969), p.
187.
1863.
Sept.
30, 1943: Yahil (1969), p.
328, puts this meeting “the day aer
[Bohr’s] arrival in Stockholm,” i.e., Oct.
1, 1943.
But cf.
Rozental
(1967), p.
168: “on the same evening....”
1864.
“went to...
of Sweden”: Rozental (1967), p.
169.
1865.
contacted the Danish ambassador: Yahil (1969), p.
330.
1866.
“e audience...
operation”: Rozental (1967), p.
169.
1867.
“At the...
received”: quoted in Yahil (1969), p.
219.
1868.
“e stay...
in Sweden”: Rozental (1967), p.
195.
1869.
“e Royal...
as Bohr’s”: Oppenheimer (1963), III (Los Alamos
version), p.
7.
1870.
“e Mosquito...
conscious again”: Rozental (1967), p.
196.
1871.
“Once in...
going on”: Oppenheimer (1963), III, p.
7.
1872.
“good first...
years before”: ibid., p.
8.
1873.
“e work...
expected”: Rozental (1967), p.
196.
1874.
“To Bohr...
fantastic”: Oppenheimer (1963), III, p.
7.
Chapter 15: Different Animals
1875.
“depends on...
its mass”: Brobeck and Reynolds (1945), p.
4.
1876.
“When the...
of metal”: ibid., p.
5.
1877.
100-microgram sample: ibid., p.
7.
1878.
“that...
be assured”: EOL to LRG, Aug.
3, 1943.
Bush-Conant file, f.
19.
1879.
“At one...
Troy ounce”: Groves (1962), p.
107.
1880.
electromagnetic separation buildings: “Pertinent reference data,
CEW.” Dec.
1, 1944.
MED 319.1 , p.
3ff.
1881.
20,000 workers: W.
E.
Kelley to W.
H.
Marsden, Aug.
9, 1943.
MED
misc., f.
4.
1882.
40 kg U235: JRO to LRG, Sept.
25, 1943, p.
3 MED 337.
1883.
Army engineer’s summary: W.
E.
Kelley to E.
H.
Marsden, Aug.
9,
1943.
MED misc., f.4.
1884.
one supervisor remembers: interview with Leon Love, Oak Ridge,
Tenn., 1975.
1885.
“moved the...
they belonged”: Groves (1962), p.
105ff.
1886.
“e first...
shorting”: ibid., p.
104ff.
1887.
Dunning’s staff: Cohen (1983), p.
641.
1888.
“three methods...
method”: quoted in ibid., p.
637ff.
1889.
“e method...
stages”: Groves (1962), p.
111.
1890.
“Further...
be solved”: quoted in Cohen (1983), p.
637ff.
1891.
2,892 stages: Cave Brown (1977), p.
311.
1892.
“from that...
applications”: Cohen (1983), p.
643.
1893.
“e Clinton...
inoperable”: Groves (1962), p.
69ff.
1894.
real estate appraisal: “Gross Appraisal, Gable Project.” Jan.
21, 1943.
MED 319.1.
1895.
Hanford description: ibid.
1896.
dimensions: Cave Brown (1977), p.
322.
1897.
1:4000: Seaborg (1977), p.
548.
1898.
“With water...
arise”: Compton (1956), p.
170.
1899.
“the conscience...
very end”: Weart and Szilard (1978), p.
148.
1900.
“Local storms...
dust”: Libby (1979), p.
167.
1901.
“e most...
guns”: quoted in Groueff (1967), p.
141.
1902.
“was a...
morning”: Libby (1979), p.
167.
1903.
“work gangs...
the year”: Hewlett and Anderson (1962), p.
216ff.
1904.
Forty-foot pile building: Hewlett and Anderson (1962), p.
217, give 120 feet; that measurement includes the detached exhaust stack,
however.
Cf.
Libby (1979), p.167 , and Hewlett and Anderson (1962),
photo following p.
224.
1905.
“ere was...
animals”: Badash (1980), p.
91.
1906.
“Years later...
that”: Teller (1962), p.
211.
1907.
Soviet research: cf.
York (1976), p.
29ff; Alexandrov (1967);
Golovin (1967); Szulc (1984).
1908.
“e advance...
safety”: Golovin (1967), p.
14.
1909.
“In recent...
inhabitants”: quoted in York (1976), p.
30.
1910.
“no time...
bomb”: ibid.
1911.
“So it...
places”: Alexandrov (1967), p.
12.
1912.
“Even so...
isotopes”: York (1976), p.
31.
1913.
Groves’ anti-Semitism: cf.
transcript of Groves interview of March
8, 1946, Szilard Papers: “Only a man with [Szilard’s] brass would
have pushed through to the President.
Take Wigner or Fermi—
they’re not Jewish—they’re quiet, shy, modest, just interested in
learning...
Of course, most of [Szilard’s] ideas are bad, but he has
so many....
And I’m not prejudiced.
I don’t like certain Jews and I
don’t like certain well-known characteristics of theirs but I’m not
prejudiced.”
1914.
“If the...
bomb”: Smith (1965), p.
27.
1915.
“ere is...
obsolete”: Weart and Szilard (1978), p.
165.
1916.
TO REMOVE...
NOW: AHC to LRG.
Oct.
26, 1942.
MED 201, Leo
Szilard.
1917.
SZILARD...
MYSELF: AHC to LRG, Oct.
28, 1942.
MED 201, Leo
Szilard.
1918.
“enemy alien...
war”: dra Sec.
of War to Atty.
Gen., Oct.
28,
1942.
MED 201, Leo Szilard.
1919.
Compton to Groves mid-November: Nov.
13, 1942.
MED 201, Leo
Szilard.
1920.
“for inventions...
it”: LS to AHC, Dec.
4, 1942.
Bush-Conant File,
f.
13.
1921.
Compton to Briggs: cf.
AHC to JBC, Jan.
7, 1943.
Bush-Conant File, f.
13.
1922.
“the basic...
inventions”: LS to AHC, Dec.
29, 1942.
MED 072,
Szilard patents.
1923.
$750,000: undated memorandum, “Leo Szilard,” p.
3.
MED 12,
Intelligence and security.
1924.
“Szilard’s case...
Government”: AHC to JBC, Jan.
7, 1943.
Bush-
Conant File, f.
13.
1925.
“is is...
present”: LS to AHC, Jan.
13, 1943.
MED 072, Szilard
patents.
1926.
“It is...
research”: VB to AHC, Jan.
29, 1943.
Bush-Conant File, f.
13.
1927.
“comparable...
Wigner”: AHC to JBC, Feb.
3, 1943.
MED 072.
Compton notes at the head of this letter that it was never sent but
was communicated orally.
1928.
“e investigation...
person”: LRG to Capt.
Calvert, June 12,
1943.
MED 201.
1929.
“e surveillance...
to go”: “Memorandum for the officer in
charge,” June 24, 1943.
MED 201.
1930.
“Age, 35...
no hat”: ibid.
1931.
“(Mr.
Wigner...
the Navy”: ibid.
1932.
“failed to...
pile”: RAL to LRG (n.d.), “copy made for Maj.
Peterson 8-2-43.” MED 072.
1933.
“You were...
assurance”: LRG to LS, Oct.
9, 1943.
MED 201.
1934.
Dec.
3 Chicago meeting: H.
E.
Metcalfe, “A memorandum of a
conference held át the Chicago Area Office, U.S.
Engineers, on 3
December 1943.” MED 072.
1935.
“not to...
person”: LRG to LS, Oct.
8, 1943.
MED 072.
1936.
“who at...
around me”: LS to VB, Jan.
14, 1944.
Bush-Conant File,
f.
13.
Reprinted in Weart and Szilard (1978), p.
161ff.
1937.
“I feel...
project”: VB to LS, Jan.
18, 1944.
Bush-Conant File, f.
13.
1938.
“the only...
at present”: Weart and Szilard (1978), p.
165.
1939.
“e attitude...
initiative”: ibid., p.
177.
1940.
“e scientists...
are out”: ibid., p.
178.
1941.
Fermi and poisoning food: cf.
JRO to EF, May 25, 1943.
JRO
Papers, Box 33.
1942.
Met Lab worries: cf.
A.
H.
Compton, J.
B.
Conant, H.
Urey,
“Radioactive material as a military weapon.” MED 319.1 , Literature.
Appendix IV, p.
7.
1943.
May 1943/before February: May is the month of JRO’s letter to
Fermi, which mentions the subcommittee; February is the date of a
table of biological effects given in ibid., Appendix I, p.
4ff.
1944.
“I therefore...
than this”: JRO to EF, May 25, 1943.
JRO Papers,
Box 33.
1945.
“the Sanscrit...
or hurt”: quoted in Davis (1968), p.
330.
1946.
“Recent reports...
large companies”: HAB and ET to JRO, July 21,
1943.
JRO Papers, Box 20.
1947.
Conant subcommittee report: MED 319.1.
1948.
Cosmos Club: Irving (1967), p.
166.
1949.
Vemork bombing and ferry sinking: cf.
ibid., p.
174ff; Haukelid
(1954), p.
149ff.
1950.
97.6 to 1.1 percent: Irving (1967), p.
188.
1951.
“a one-man...
another”: Haukelid (1954), p.
156.
1952.
“e fact...
at all”: ibid., p.
160.
1953.
“e answer...
Greetings”: ibid., p.
161.
1954.
“We had...
place”: ibid., p.
163.
1955.
“As the...
enough”: ibid., p.
167ff.
1956.
“e timing...
properly”: ibid., p.
163.
1957.
“Rolf...
at ten”: ibid., p.
165.
1958.
“Armed with...
took time”: ibid., p.
166ff.
1959.
“e charge...
side”: ibid., p.
167.
1960.
“Making the...
disaster”: ibid., p.
168.
1961.
“When one...
war ended”: quoted in Irving (1967), p.
191.
1962.
“Europe was...
stepchild”: quoted in Costello (1981), p.
354.
1963.
“very uneasy...
monkeys”: Hersey (1942), p.
36.
1964.
“e other...
the Japs”: Grew (1942), p.
81.
1965.
“e Japanese...
and nations”: ibid., p.
79.
1966.
“united...
totalitarian”: ibid., p.
80.
1967.
“At this...
to fight”: ibid., p.
80ff.
1968.
“ ‘Victory or...
his country”: ibid., p.
82.
1969.
“General...
hand grenade”: quoted in Manchester (1980), p.
183.
1970.
“A legend...
or dead”: Hersey (1942), p.
36.
1971.
“in the...
cause”: Grew (1942), p.
80.
1972.
“At the...
defeat it”: Manchester (1980), p.
240.
1973.
“e general...
isolated cases”: Tregaskis (1943), p.
79.
1974.
“1 know...
fighting Japan”: Grew (1942), p.
82.
1975.
“It seems...
the enemy”: Wolfe (1943), p.
190.
1976.
unconditional surrender: cf.
Churchill (1950), p.
695ff.
1977.
“We had...
war effort”: quoted in ibid., p.
687.
Chapter 16: Revelations
1978.
“How would...
night train”: Frisch (1979), p.
145ff.
1979.
hearse: Clark (1980), p.
154.
1980.
“I wandered...
laughter”: Frisch (1979), p.
148.
1981.
“Welcome...
you?”: quoted in ibid., p.
150.
1982.
Quebec Agreement: for complete text cf.
Gowing (1964), p.
439ff.
1983.
Bohr’s luggage: cf.
Frisch (1979), p.
169.
1984.
“It was...
London”: quoted in Bernstein (1980), p.
77.
1985.
“Explosion...
of pile”: MED 337.
Cf.
also JRO to LRG, Jan.
1,
1944, same file.
1986.
“At that...
Bohr”: Goudsmit (1947), p.
177.
1987.
“Bohr at...
one”: Oppenheimer (1963), III (Los Alamos version),
p.
10ff.
1988.
“made...
hopeful”: Oppenheimer (1963), III, p.
11.
1989.
“He made...
misgiving”: Oppenheimer (1963), III (Los Alamos
version), p.
11.
1990.
“Bohr spoke...
believe”: ibid.
1991.
“In Los...
from him”: quoted in Moore (1966), p.
330.
1992.
“ey...
bomb”: quoted in Nielson (1963), p.
29.
1993.
“warm...
relation”: FF memorandum headed “Private,” April 18,
1945.
JRO Papers, Box 34.
1994.
“We talked...
Campbell”: ibid.
1995.
“On hearing...
B outlined”: unsigned Bohr memorandum, May 6,
1945.
JRO Papers, Box 34.
1996.
“B met...
in history”: ibid.
1997.
“On this...
to X”: FF memorandum, April 18, 1945.
1998.
“F also...
Minister”: NB memorandum, May 6, 1945.
1999.
“I wrote...
government”: FF memorandum, April 18, 1945.
2000.
“Halifax...
immediately”: Rozental (1967), p.
203.
2001.
“conservative...
man”: Oppenheimer (1963), III (Los Alamos
version), p.
8.
2002.
Anderson memorandum, March 21, 1944: cf.
Clark (1980), p.
169
—where a portion is quoted confusingly aer a later memorandum
—and Gowing (1964), p.
350ff.
2003.
“communicating...
account”: quoted in Clark (1980), p.
169.
2004.
“I do...
informed”: quoted in Gowing (1964), p.
352.
2005.
“to let...
work”: PK to NB, Oct.
23, 1943.
JRO Papers, Box 34.
2006.
“e Counsellor...
the occupation”: “Conversation between B and
Counsellor Zinchenko at the Soviet Embassy in London on April
20th, 1944, at 5 p.m.” JRO Papers, Box 34.
2007.
“We came...
new prospects”: Rozental (1967), p.
203.
2008.
“One of...
the war”: Snow (1981), p.
112.
2009.
R.
V.
Jones: cf.
Jones (1966), p.
88ff.
2010.
“When I...
Roosevelt”: ibid., p.
88.
2011.
“As he...
politics!”: Rozental (1967), p.
204.
2012.
“We...
language”: quoted in Gowing (1964), p.
355.
2013.
“downcast”: Rozental (1967), p.
204.
2014.
“It was...
nuclear energy”: quoted in Nielson (1963), p.
29.
2015.
“I did...
Street”: quoted in Clark (1980), p.
177.
2016.
“In all...
present time”: quoted in Sherwin (1975), p.
108.
2017.
“He had...
sad story”: Snow (1981), p.
116.
2018.
“that the...
their decisions”: NB to WC, May 22, 1944.
JRO
Papers, Box 34.
2019.
“e way...
Berlin”: Chandler (1970), III, p.
1865.
2020.
“About a...
memorandum”: NB memorandum, May 6, 1945.
2021.
“It was...
manual skill”: Rozental (1967), p.
205ff.
2022.
Bohr FDR memorandum: July 3, 1944.
JRO Papers, Box 21.
Relevant portions of the text of this unpublished document are
quoted in NB’s “Open Letter to the United Nations” reprinted in
Rozental (1967), p.
341.
2023.
“We are...
by war”: quoted in Nielson (1963), p.
29ff.
My italics.
2024.
“First of...
of war”: Oppenheimer (1963), III (Los Alamos
version) p.
8.
2025.
“a far...
warfare”: NB memorandum, July 3, 1944.
2026.
“It appeared...
divergencies”: Rozental (1967), p.
341.
My italics.
2027.
“Much thought...
confidence”: NB memorandum, July 3, 1944.
2028.
“e prevention...
acuteness”: ibid.
2029.
“[Bohr]...
the world”: Oppenheimer (1963), III (Los Alamos
version) p.
9.
2030.
“What it...
enlarged upon”: quoted in ibid.
2031.
“Within any...
openness”: Rozental (1967), p.
350.
2032.
“An open...
else”: ibid.
2033.
“e very...
crisis”: ibid., p.
351.
2034.
“e present...
the others”: NB memorandum, July 3, 1944.
2035.
“I have...
purpose”: NB to FF, July 6, 1944.
JRO Papers, Box 34.
2036.
“on August...
manner”: NB memorandum, May 6, 1945.
2037.
“was very...
spirits”: Rozental (1967), p.
205.
2038.
“most kindly...
entertained”: NB memorandum, May 6, 1945.
2039.
“Roosevelt...
aerwards”: Rozental (1967), p.
206ff.
2040.
“le with...
Union”: unsigned memorandum “Notes on Bohr”
dated May 20, 1948, on the stationery of the office of the Director of
the Institute for Advanced Study.
JRO Papers, Box 21.
2041.
“It is...
expectation”: Rozental (1967), p.
207.
2042.
“is was...
of Bohr”: Snow (1981), p.
116.
2043.
“e suggestion...
Russians”: quoted in Gowing (1964), p.
447.
2044.
“e President...
at all”: quoted in Clark (1981), p.
177.
2045.
“youthful...
physicists”: Ulam (1976), p.
151.
2046.
“It was...
major voice”: Bethe (1982).
Communicated in
manuscript; Ms.
p.
2.
2047.
thermonuclear research: cf.
Hawkins (1947), p.
24.
2048.
“at I...
inevitable”: quoted in Bernstein (1980), p.
81.
2049.
“Bethe was...
organization”: quoted in Blumberg and Owens
(1976), p.
129ff.
2050.
“roughout the...
led it”: Teller (1983), p.
190ff.
2051.
“I believe...
Oppenheimer”: quoted in Blumberg and Owens
(1976), p.
129ff.
2052.
“When Los...
objectives”: Teller (1955), p.
269.
2053.
the laboratory history confirms: cf.
Hawkins (1947), p.
96.
2054.
“At this...
dream of”: Segrè (1970), p.
137.
2055.
“e first...
out there”: Badash (1980), p.
17.
2056.
bullet passing through: cf.
Hawkins (1947), p.
131.
2057.
“the first...
illusions”: ibid., p.
77.
2058.
“Absolutely...
results”: quoted in Bernstein (1980), p.
85.
2059.
“Everything in...
everybody”: Badash (1980), p.
49.
2060.
“by 1943...
ordnance”: ibid.
2061.
GK won JvN to his view: interview with George Kistiakowsky,
Cambridge, Mass., Jan.
15, 1982.
2062.
“I began...
at times”: Badash (1980), p.
49ff.
2063.
“Aer a...
interfering”: quoted a Goodchild (1980), p.
112ff.
2064.
“It seemed...
effort”: Ulam (1976), p.
141.
2065.
“e sun...
Madison”: ibid., p.
145.
2066.
“talked to...
bomb”: ibid., p.
148ff.
2067.
“However...
to do”: Bethe (1982), Ms.
p.
2.
2068.
“[Bethe]...
novel subjects”: quoted in Blumberg and Owens
(1976), p.
131.
2069.
“Both...
main program”: Hawkins (1947), p.
97.
2070.
“the hydrodynamical...
magnitude”: Ulam (1976), p.
154.
2071.
“all the...
work”: ibid., p.
154ff.
2072.
“You have...
the charge”: Kistiakowsky interview, Jan.
15, 1982.
2073.
5 percent variation: Hawkins (1947), p.
91.
2074.
“With the...
bomb”: Bethe (1982), Ms.
p.
3.
2075.
“ese calculations...
urgency”: JRO to LRG, May 1, 1944.
MED
201, Peierls, R.
2076.
“Oppenheimer...
was feasible”: Teller (1955), p.
269.
2077.
“But there...
Teller”: quoted in Smith and Weiner (1980), p.
273.
2078.
Kistiakowsky memorandum: GBK to JRO, June 3, 1944.
JRO
Papers, Box 43.
2079.
“I am...
accept it”: quoted in Kunetka (1979), p.
88.
2080.
2000+ experiments: 2,500; cf.
Smith and Weiner (1980), p.
282.
2081.
“It appears...
implosion”: JRO to LRG, July 18, 1944.
Bush-
Conant File, f.
3.
2082.
“e implosion...
one”: Hawkins (1947), p.
82.
2083.
“e Laboratory...
at it’ ”: ibid.
2084.
“[Oppenheimer]...
of me”: quoted in Goodchild (1980), p.
118.
2085.
1,207 employees: “Personnel employed at ‘Y’ technical area, May 1,
1944.” MED 201, Personnel.
2086.
“it had...
a barn”: interview with Philip Abelson, Washington,
D.C., Sept.
17, 1982.
2087.
the dollar: ibid.
2088.
thermal diffusion experiments: cf.
Abelson (1943).
2089.
“e apparatus...
device”: ibid., p.
5.
2090.
“Information...
future plants”: ibid., p.
20.
2091.
“ey were...
steam”: Abelson interview, Sept.
17, 1982.
2092.
Abelson knew Manhattan Project: ibid.
2093.
“I wanted...
dagger stuff”: telephone interview with Philip
Abelson, Oct.
16, 1984.
2094.
BuOrd man: Hewlett and Anderson (1962), p.
168, cite a visit by
Deke Parsons to the Navy Yard as the origin of this contact.
Abelson
remembers no such visit.
e official AEC historians apparently
found the Parsons version in JRO’s memorandum to LRG.
Groves
was concerned aer the war to discredit a Szilard recounting of this
story similar to Abelson’s version.
Abelson remembers quite clearly
that he initiated the contact; asked if he deliberately breached
compartmentalization, he answers, “I sure as hell did!” Telephone
interview, Oct.
16, 1984.
2095.
“Dr.
Oppenheimer...
a whole”: USAEC (1954), p.
164ff.
2096.
“I at...
investigating”: Groves (1962), p.
120.
2097.
Lewis/Murphree/Tolman conclusions: cf.
“Possible utilization of
Navy pilot thermal diffusion plant,” dated June 3, 1944.
Bush-
Conant File, f.
3.
2098.
“Chinese copies”: Groves (1962), p.
120.
2099.
“We are...
Marines”: quoted in Costello (1981), p.
476.
2100.
“Nowhere have...
was dead”: Sherrod (1944), p.
32.
2101.
Tinian: cf.
esp.
Hough (1947).
2102.
“e view...
cold”: Libby (1979), p.
177.
2103.
“Enrico and...
reaction”: ibid., p.
178ff.
2104.
“We arrived...
cooling tubes”: ibid., p.
179ff.
2105.
“Something was...
and down”: ibid., p.
180ff.
2106.
Fermi open-minded: cf.
ibid., p.
181.
2107.
“concerned for...
even stable”: Wheeler (1962), p.
34.
2108.
“If this...
was needed”: ibid., p.
34ff.
2109.
“a fundamentally...
matter”: quoted in Hewlett and Anderson
(1962), p.
307.
2110.
Groves’ report to Marshall: cf.
J.
B.
Conant handwritten “Notes on
history of S-1” dated Jan.
6, 1945.
Bush-Conant File, f.
19.
2111.
“Looks like...
September”: ibid.
Chapter 17: The Evils of This Time
2112.
Conant to Bush: “Report on visit to Los Alamos—October 18,
1944.” Bush-Conant File, f.
3.
2113.
“what the...
over”: Conant (1970), p.
300.
2114.
Niels Bohr: NB’s influence on VB and JBC can be traced by careful
reading.
e two administrators knew little or nothing of NB’s ideas
on Sept.
19, 1944, when they sent their own to HLS: when VB met
with Cherwell and FDR on Sept.
22, VB was disturbed that FDR was
discussing postwar arrangements without benefit of briefing and
gathered, apparently from FDR, that NB wanted the British and the
Americans to maintain peace via bilateral postwar monopoly.
Between Sept.
22 and 30, however, at least VB must have talked to
NB: the memorandum he and JBC sent HLS on that later date
contains and endorses all NB’s basic ideas.
Since Bohr was in the
doghouse with FDR at the time, VB and JBC were probably politic
not to credit him as their source.
Cf.
VB/JBC to HLS, Sept.
19, 1944,
MED 76, S-l interim committee scientific panel; VB to JBC,
“Memorandum of conference,” Sept.
22, 1944, Bush-Conant File, f.
20a; VB to JBC, Sept.
23, 1944, ibid.; VB/JBC to HLS, Sept.
30, 1944,
Bush-Conant File, f.
20a.
2115.
“the progress...
be secure”: VB/JBC to HLS, Sept.
19, 1944.
2116.
“to a...
Russia”: VB to JBC, Sept.
22, 1944.
2117.
“In order...
attempt”: VB/JBC to HLS, Sept.
30, 1944.
2118.
“a robot...
missile”: ibid.
2119.
“By various...
enterprise”: JBC to VB, Oct.
20, 1944.
Bush-Conant
File, f.
3.
2120.
“I should...
importance”: USAEC (1954), p.
954ff.
2121.
Los Alamos: is discussion draws especially on Badash (1980),
Brode (1960), L.
Fermi (1954), Jette (1977), Libby (1979), Lyon and
Evans (1984) and Segrè (1970).
2122.
“I always...
rebellion”: L.
Fermi (1954), p.
231ff.
2123.
“I told...
come again”: quoted in Brode (1960), I, 7.
2124.
“en we...
slope”: Badash (1980), p.
61.
2125.
“Oppie...
get up”: quoted in L.
Fermi (1954), p.
227.
2126.
“at young...
long way”: quoted in ibid., p.
219.
2127.
“Parties...
we worked”: Brode (1960), X, 5.
2128.
“Everybody...
army camp”: Else (1980), p.
9.
2129.
“He offered...
feet”: Brode (1960), VIII, 5.
2130.
“e main...
mesa”: ibid., X, 7.
2131.
“I played...
of view”: Badash (1980), p.
61.
2132.
“Of the...
cloth”: Wilson (1975), p.
160.
2133.
“I don’t...
friendship”: Badash (1980), p.
43.
2134.
“e streams...
shouting”: quoted in Brode (1960), IX, 7.
2135.
“but he...
science”: Segrè (1970), p.
140.
2136.
“Oh, I...
wits”: quoted in Ulam (1976), p.
165.
2137.
“sit there...
made”: Badash (1980), p.
81.
2138.
“nothing...
breath”: Libby (1979), p.
204ff.
2139.
“Best for...
Fuchs”: Brode (1960), IX, 7.
2140.
“Remember...
Park”: quoted in Lyon and Evans (1984), p.
31.
2141.
“from...
cover”: Hans Bethe OHI, AIP, p.
159.
2142.
“Jesus...
fantastic”: Jette (1977), p.
84.
2143.
“Oppenheimer...
exception”: interview with Edward Teller,
Stanford, Calif., June 19, 1982.
2144.
“He knew...
us”: Else (1980), p.
10.
2145.
“He understood...
anybody”: interview with Hans Bethe, Ithaca,
N.Y., Sept.
12, 1982.
2146.
“a very...
them”: “Seven Springs meeting, 5/63,” p.
5.
JRO Papers,
Box 66.
2147.
volunteered names to protect his own: cf.
Stern and Green (1969),
p.
48ff.
2148.
“On June...
together”: D.
M.
Ladd to Director FBI, Dec.
17, 1953,
p.
9.
JRO FBI file, doc.
65.
2149.
“I wanted...
somehow”: quoted in Goodchild (1980), p.
128.
2150.
between March and October: between the beginning of planning
and the first mention of Trinity I find in the record, JBC to VB, Oct.
18, 1944.
2151.
“I did...
Resurrection”: JRO to LRG, Oct.
20, 1962.
JRO Papers,
Box 36.
2152.
“Bohr was...
control”: Hans Bethe OHI, AIP, p.
62.
2153.
“at still...
whatever”: JRO to LRG, Oct.
20, 1962.
2154.
Oppenheimer did not doubt: cf.
his famous remark to Truman that
he had blood on his hands.
2155.
healed the split: cf.
Dyson (1979), p.
81ff, esp.
Kitty Oppenheimer’s
choice of George Herbert’s “e Collar” as “a poem...
that she
found particularly appropriate to describe how Robert had appeared
to himself.” “e Collar” works complementarities similar to
Donne’s.
2156.
“erefore I...
peace”: Smith and Weiner (1980), p.
156.
2157.
“I was...
surrounded”: interview with Luis Alvarez, Berkeley,
Calif., June 22, 1982.
2158.
“very quickly...
failed”: Bethe interview, Sept.
12, 1982.
2159.
“too frequently...
shortcuts”: Kistiakowsky (1949a), I-1.
2160.
“Prior to...
low”: ibid., I-2.
2161.
“So much...
implosion”: Badash (1980), p.
54.
2162.
“the greatest...
molds”: interview with George Kistiakowsky,
Cambridge, Mass., Jan.
15, 1982.
2163.
Composition B/Baratol: cf.
Kistiakowsky (1949b).
2164.
“We learned...
mold”: Kistiakowsky interview, Jan.
15, 1982.
2165.
“We were...
charges”: Kistiakowsky (1980), p.
19.
2166.
initiator: Dr.
Louis Brown, DTM, Carnegie Institution of
Washington, contributed valuably to this discussion.
2167.
“some other...
satisfactory”: Condon (1943), p.
19.
2168.
“I think...
initiator”: Bethe interview, Sept.
12, 1982.
2169.
“is isotope...
accord”: quoted in Trenn (1980), p.
98.
2170.
screwballs: cf.
Groueff (1967), p.
327.
2171.
Nishina’s private belief: cf.
Pacific War Research Society (1972)
(hereaer PWRS), p.
23.
2172.
first Nishina/Nobuuji meeting: “Uranium project research
meeting,” July 2, 1943.
Copies of original documents and
translations in the private collection of P.
Wayne Reagan, Kansas
City, Mo.
2173.
second Nishina/Nobuuji meeting: “Uranium project research
meeting,” Feb.
2, 1944.
P.
Wayne Reagan collection.
2174.
170 grams: PWRS (1972), p.
48.
2175.
“Well, don’t...
gas”: quoted in ibid., p.
49.
2176.
third Nishina/Nobuuji meeting: “Uranium project research
meeting,” Nov.
17, 1944.
P Wayne Reagan collection.
2177.
Nishina’s staff had understood: cf.
PWRS (1972), p.
41.
2178.
“e doors...
doors”: Ramsey (1946), p.
126.
2179.
“When I...
right”: quoted in Marx (1967), p.
98.
2180.
“I’m satisfied”: quoted in Tibbets (1973), p.
51.
2181.
“You have...
war”: ibid.
2182.
Air Force chose Wendover: Tibbets has remembered making the
choice, but it was determined before his appointment; no doubt he
confirmed it.
Cf.
Capt.
Derry to LRG, Aug.
29, 1944.
MED 5c,
Preparation and movement of personnel and equipment to Tinian.
2183.
B-29: cf.
Birdsall (1980).
2184.
Sept.
1939 proposal: ibid., p.
2.
2185.
one Delivery group physicist: David L.
Anderson interview,
Oberlin, Ohio, 1981.
2186.
“safe...
of two”: Groves (1962), p.
286.
2187.
Tibbets: besides previous references cf.
also omas and Witts
(1977).
2188.
“It didn’t...
homeland”: LeMay (1965), p.
322.
2189.
“I’ll tell...
fighting”: quoted in Powers (1984), p.
60.
2190.
“I wanted...
creature”: LeMay (1965), p.
14.
2191.
“truancy...
mania”: ibid., p.
16.
2192.
“I had...
activities”: ibid., p.
17.
2193.
“When the...
penetrate”: ibid., p.
30.
2194.
“General Arnold...
system”: ibid., p.
338.
2195.
“e city...
of it”: Guillain (1981), p.
174.
2196.
Hansell target directive: cf.
Birdsall (1980), p.
107.
2197.
“I did...
surprise”: quoted in ibid., p.
144.
2198.
blockbluster meeting: on Dec.
19, 1944.
Cf.
Capt.
Derry to LRG,
Jan.
9, 1945.
MED 4, Trinity test.
2199.
Parsons memorandum: WSP to LRG, Dec.
26, 1944.
MED 51,
Memos from Parsons (misc).
2200.
“Suddenly there...
blossom”: Guillain (1981), p.
176.
2201.
“urgent...
future planning”: quoted in Birdsall (1980), p.
131,
whose argument I follow here.
2202.
“LeMay is...
it”: quoted in ibid., p.
143.
2203.
“General Arnold...
lives”: LeMay (1965), p.
347.
2204.
“another month...
this”: ibid., p.
345.
2205.
Churchill instigated: cf.
Irving (1963), p.
90ff.
2206.
“I did...
done”: quoted in ibid., p.
92.
2207.
“e first...
underground”: I was the interviewer.
Rhodes et al.
(1977), p.
213ff.
2208.
Iwo Jima: cf.
esp.
Wheeler (1980).
2209.
“We would...
can”: quoted in ibid., p.
28.
2210.
“I am...
can”: quoted in ibid., p.
29.
2211.
“ey meant...
homeland”: Manchester (1980), p.
339.
2212.
poison gas: cf.
Wheeler (1980), p.
13.
2213.
“e invaders...
flesh”: Manchester (1980), p.
340.
2214.
“We shall...
dying!”: quoted in Costello (1981), p.
546.
2215.
“e Japanese...
fast”: LeMay (1965), p.
346; his italics.
2216.
Tokyo raid: cf.
United States Strategic Bombing Survey (1976)
(hereaer USSBS); Birdsall (1980); Guillain (1981); Kennett (1982);
Overy (1980).
2217.
“All the...
kids”: LeMay (1965), p.
349.
2218.
87.4 percent: USSBS #96, p.
105.
2219.
“No matter...
killed”: LeMay (1965), p.
352; his ellipses.
2220.
“the entire...
target”: quoted in Kennett (1982), p.
176.
2221.
“outstanding strike”: quoted in Birdsall (1980), p.
180.
2222.
Arnold informed: LeMay remembers otherwise, but cf.
ibid.
2223.
“You’re going...
seen”: quoted in Costello (1981), p.
548.
2224.
“grim...
grubby”: Brines (1944), p.
292.
2225.
“We will...
possible”: ibid., p.
9.
2226.
“American fighting...
way”: ibid., p.
11.
2227.
“e inhabitants...
everywhere”: Guillain (1981), p.
184.
2228.
“e fire...
spectacle”: ibid., p.
182.
2229.
“e chief...
wind”: USSBS #96, p.
96ff.
2230.
“the most...
known”: quoted in Birdsall (1980), p.
195.
2231.
“probably more...
man”: USSBS #96, p.
95.
2232.
CONGRATULATIONS...
ANYTHING: quoted in Birdsall (1980), p.
196.
2233.
“en...
Literally”: LeMay (1965), p.
354.
2234.
32 sq.
mi.: USSBS #96, p.
39.
2235.
“I consider...
command”: quoted in Overy (1980), p.
100.
2236.
“In order...
mud”: quoted in Johnson and Jackson (1981), p.
19.
2237.
100 gms., etc.: these numbers and dates from M.
L.
Oliphant to J.
Chadwick, Nov.
2, 1944.
MED 201, Chadwick, J.
2238.
“is loss...
management”: ibid.
2239.
“the output...
expected”: MLO to LRG, Nov.
13, 1944.
MED 201,
Oliphant, M.
L.
2240.
Jan.
1945, data: Brobeck and Reynolds (1945).
2241.
Conant notes on Jan.
6: “Notes on history of S-1.” Bush-Conant
File, f.
19.
2242.
U235 critical mass: Conant cites 13 ± 2 kg in JBC to VB, Oct.
18,
1944; King (1979) cites 15 kg for U235 surrounded by a thick U
tamper.
2243.
“on the...
received”: quoted in Hewlett and Anderson (1962), p.
301.
2244.
Groves’ U235 farm: toured on a visit to Oak Ridge in 1975, when
the bluffside bunker had been converted to an air-pollution
sampling station.
2245.
250 ppm: Seaborg (1958), p.
16.
2246.
“Originally eight...
concrete”: Groves (1962), p.
85.
2247.
“When the...
alo”: Libby (1979), p.
174.
2248.
“e yields...
1945”: Seaborg (1958), p.
50ff.
2249.
“the astonishing...
date”: Goldschmidt (1964), p.
35.
2250.
“the unfortunate...
[them]”: Groves (1962), p.
186.
2251.
“but I...
it”: ibid., p.
191.
2252.
“his thorough...
me”: ibid., p.
193.
2253.
“e ALSOS...
Paris”: Lt.
Col.
G.
R.
Eckman to Chief, Military
Intelligence Service, Sept.
1, 1944.
MED 371.2 , Goudsmit mission.
2254.
“It is...
form”: Goudsmit (1947), p.
70ff.
2255.
“Washington wanted...
Union”: Pash (1969), p.
191.
2256.
“We outlined...
oxide”: JL, “Capture of material,” dra report, July
10, 1946.
MED 7, War Dept.
special operations (tab E-F).
2257.
“Many of...
started”: ibid.
Note that Groves (1962), p.
237,
remembers these paper bags as fruit barrels and invents a two-week
plant run in the midst of contending armies to manufacture them.
Such is memory; JL’s is the eyewitness account, confirmed by his
contemporary report JL to LRG, May 5, 1945.
MED 7 (tab A-C).
2258.
“Haigerloch is...
pile”: Pash (1969), p.
206ff.
2259.
Haigerloch pile: cf.
Irving (1967), p.
244ff.
2260.
“e fact...
Alsos”: Pash (1969), p.
157ff.
2261.
“By successively...
reactions”: Hawkins (1947), p.
229.
2262.
“At that...
flicker”: Frisch (1979), p.
161.
2263.
“e idea...
so”: ibid., p.
159.
2264.
Feynman named it: cf.
ibid.
2265.
“It was...
mid-morning”: ibid., p.
159ff.
2266.
“ese experiments...
alone”: Hawkins (1947), p.
230.
2267.
“In 1940...
war”: LRG to GCM, April 23, 1945.
MED 7 (tab E-F).
2268.
“Sunday morning...
ours”: quoted in Smith and Weiner (1980), p.
287.
2269.
“When, three...
death”: ibid., p.
288.
2270.
“I kept...
struck!”: quoted in Bishop (1974), p.
598.
Chapter 18: Trinity
2271.
“Stimson told...
details”: Truman (1955), p.
10.
2272.
“e chief...
distrust”: Stimson and Bundy (1948), p.
544.
2273.
“assistant President”: quoted in Byrnes (1958), p.
155.
2274.
“Jimmy Byrnes...
world”: Truman (1955), p.
11.
2275.
“that in...
war”: ibid., p.
87.
2276.
“A small...
geniality”: Joseph Alsop and Robert Kitner, quoted in
Mee (1975), p.
2.
2277.
“a vigorous...
politics”: quoted in ibid.
2278.
“Had a...
sometimes”: Ferrell (1980), p.
39.
2279.
“I freely...
action”: Byrnes (1958), p.
230.
2280.
“We proposed...
in”: “Memorandum of conference,” Dec.
8, 1944.
Bush-Conant File, f.
20a.
2281.
“I told...
me”: “Extract from notes made aer a conference with
the President, December 31, 1944.” MED 24, Memos to file by LRG
covering two meetings with the President.
2282.
“it would...
S-l”: quoted in Sherwin (1975), p.
136.
2283.
“the fear...
messages”: Truman (1955), p.
72.
2284.
“barbarian invasion...
affairs”: ibid., p.
71.
2285.
“I ended...
government’ ”: ibid., p.
72.
2286.
“go ahead...
organization”: ibid.
2287.
“He felt...
Hell”: Charles Bohlen, quoted in Giovannitti and Freed
(1965), p.
46.
Note Truman’s nearly identical language, sans cuss
word and imperative, at Truman (1955), p.
77.
2288.
“In the...
promised”: Truman (1955), p.
77.
2289.
“He said...
serious”: ibid., p.
79.
2290.
“I replied...
like that”: ibid., p.
82.
2291.
“one of...
House”: ibid., p.
85.
2292.
April 24 message from Stalin: quoted in full in ibid., p.
85ff.
2293.
Stimson memorandum: “Memo discussed with the President,”
April 25, 1945.
MED 60, S-1 White House.
2294.
“Mr.
Truman...
all”: quoted in Giovannitti and Freed (1965), p.
80.
2295.
“a great...
project”: “Report of meeting with the President,” April
25, 1945.
MED 24.
2296.
“I listened...
service”: Truman (1955), p.
87.
2297.
first Target Committee meeting: Groves (1962), p.
268, dates this
occasion May 2, 1945, but cf.
“Notes on initial meeting of target
committee” dated April 27, 1945, from which all indicated
quotations following are extracted.
MED 5D, Selection of targets.
2298.
“I had...
bomb”: Groves (1962), p.
267.
2299.
May 1 Harrison memorandum: Bush-Conant File, f.
20A.
2300.
“e President...
shut”: quoted in Giovannitti and Freed (1965),
p.
54.
2301.
“and late...
accepted”: ibid.
2302.
“were...
death”: quoted in Sherwin (1975), p.
170.
2303.
“when secrecy...
Commission”: HLS to VB, April 4, 1945.
Bush-
Conant File, f.
20b.
2304.
“I have...
scene”: Eisenhower (1970), IV, p.
2673ff.
2305.
“I tried...
accomplished”: quoted in ibid., p.
2696.
2306.
“e mission...
1945”: ibid.
2307.
deaths: from Elliot (1972) except for Holocaust victims; that number from Dawidowicz (1975), p.
544.
2308.
“We all...
committee”: quoted in Giovannitti and Freed (1965), p.
56.
2309.
Stimson introducing Byrnes: cf.
R.
Gordon Arneson,
“Memorandum for the files,” May 24, 1946.
Bush-Conant File, f.
6.
2310.
“A.
Height...
Program”: J.
A.
Derry and N.
F.
Ramsey, “Summary
of Target Committee meetings on 10 and 11 May 1945.” MED 5D.
2311.
“very frank...
one”: VB to JBC, May 14, 1945.
Bush-Conant File, f.
20B.
2312.
Stimson’s agenda: copy (misdated May 12, 1945) with notes in
HLS’s hand in Bush-Conant File, f.
100.
2313.
“I...
said...
September”: VB to JBC, May 14, 1945.
2314.
“Mr.
Byrnes...
test”: JBC to VB, May 18, 1945.
Bush-Conant File,
f.
12.
2315.
“Mr.
Byrnes...
one”: quoted in Giovannitti and Freed (1965), p.
62.
2316.
“is question...
argument”: JBC to VB, May 18, 1945.
2317.
“Some of...
matter”: ibid.
2318.
Conant told Byrnes: cf.
ibid.
2319.
“the feeling...
back”: quoted in Giovannitti and Freed (1965), p.
116ff.
2320.
“the wisdom...
bombs”: Weart and Szilard (1978), p.
182.
2321.
“many hours...
nights”: quoted in Giovannitti and Freed (1965),
p.
115.
2322.
“e only...
President”: Weart and Szilard (1978), p.
181.
2323.
“I am...
history”: quoted in Clark (1970), p.
685.
2324.
“Elated by...
House”: Weart and Szilard (1978), p.
182.
2325.
“I see...
City”: ibid., p.
183.
2326.
“We did...
know”: ibid.
2327.
“I have...
judgment”: ibid., p.
205.
2328.
Szilard memorandum: although Document 101 in ibid., p.
196ff, is
usually cited as the memorandum Byrnes read, his memory of the
contents—discussed below—makes it clear that he read the
enclosure given as part of Document 102, p.
205ff, which Weart and
Szilard describe as an “enclosure to Einstein’s letter.”
2329.
“essentially due...
armaments”: ibid., p.
198.
2330.
“Szilard complained...
me”: Byrnes (1958), p.
284.
2331.
“When I...
Russia”: Weart and Szilard (1978), p.
183.
2332.
“He said...
already?”: ibid., p.
184.
2333.
“Byrnes thought...
manageable”: ibid.
2334.
May 28 Target Committee meeting: minutes at MED 5D.
2335.
“for thirty...
hated”: Stimson and Bundy (1948), p.
632.
2336.
“I am...
weapons”: diary, quoted in Steiner (1974), p.
473.
2337.
May 30: on the evidence of LRG to Lauris Norstad, May 30, 1945,
reporting Stimson’s decision “this AM.” MED 5B.
2338.
“I was...
Kyoto”: quoted in Giovannitti and Freed (1965), p.
40ff.
2339.
“e Joint...
Japan”: quoted in Feis (1966), p.
7.
2340.
“with the...
lives”: quoted in ibid., p.
8.
2341.
31,000 casualties: cf.
ibid., p.
8ff.
2342.
Groves had doubted: cf.
VB to JBC, May 14, 1945.
2343.
“I told...
well”: Weart and Szilard (1978), p.
185.
2344.
May 31 Interim Committee meeting: cf.
notes at Bush-Conant File,
f.
100.
2345.
“S.l ...
World Peace”: handwritten notes “To the Four,” May 31,
1945.
Bush-Conant File, f.
100.
2346.
“a terrible...
breached”: Oppenheimer (1961), p.
11.
2347.
“As I...
weapon”: the deleted phrase is “and industrialists.” Byrnes
would not meet with the industrialists until the next day and
presumably merges the two meetings in memory.
e context is the
May 31 meeting.
Byrnes (1958), p.
283.
2348.
“Bush and...
panel”: Oppenheimer (1963), III (Los Alamos
version), p.
15.
2349.
question mentioned during morning: according to E.
O.
Lawrence;
cf.
Sherwin (1975), p.
207.
2350.
“[Stimson emphasized]...
harm”: Oppenheimer (1961), p.
12.
2351.
“You ask...
know”: quoted in Giovannitti and Freed (1965), p.
104.
2352.
“We feared...
surrender”: Byrnes (1958), p.
261.
2353.
“e President...
knows”: quoted in Feis (1966), p.
47.
2354.
“number of...
raids”: quoted in Sherwin (1975), p.
207ff.
2355.
20,000 deaths: Compton (1956), p.
237.
2356.
“a city...
lives”: ibid.
AHC locates this discussion A.M.
P.M.
is
likelier; much else in his memory of this meeting is misplaced.
2357.
“We were...
done”: LeMay (1965), p.
384.
2358.
“secret intelligence...
intentionally”: unsigned memorandum
dated June 1, 1945, on War Dept.
stationery; Top Secret
classification authorized by LRG.
MED 12.
2359.
June 1 Interim Committee meeting: minutes at MED 100.
2360.
“I concluded...
bomb”; quoted in Feis (1966), p.
44.
2361.
“sternly questioned”: Stimson and Bundy (1948), p.
632.
2362.
“I told...
understood”: Stimson’s diary, quoted in Giovannitti and
Freed (1965), p.
36.
2363.
“Mr.
Byrnes...
weapon”: quoted in ibid., p.
107.
2364.
Byrnes to White House: ibid., p.
109.
2365.
“I told...
recommend”: quoted in ibid., p.
110.
2366.
“said that...
done”: quoted in ibid.
2367.
“I was...
happen”: Oppenheimer (1963) III (Los Alamos version),
p.
15.
2368.
“Do you...
No”: MED 19, Bohr, Dr.
Niels.
2369.
Trinity: cf.
esp.
Badash (1980), Bainbridge (1945), Else (1980),
Lamont (1965), Szasz (1984), and Wilson (1975).
2370.
“was one...
desert”: Hawkins (1947), p.
271.
2371.
“followed unmapped...
winds”: Wilson (1975), p.
210.
2372.
“almost to...
1945”: Bainbridge (1945), p.
5.
2373.
“people were...
explosion”: Else (1980), p.
16.
2374.
Pu critical mass: cf.
King (1979), p.
7.
2375.
“Most troublesome...
lot”: Kistiakowsky (1980), p.
20.
2376.
June 27 LRG/JRO/WSP meeting: JRO/WSP to LRG, June 29, 1945.
MED 50.
Preparations and movement of personnel to Tinian.
2377.
“on purpose...
time”: quoted in Sherwin (1975), p.
193.
2378.
“What are...
propagandist?”: quoted in Szasz (1984), p.
65.
2379.
ANY...
DAYS: quoted in Groueff (1967), p.
340.
2380.
July 9: Bainbridge (1945), p.
39.
2381.
“In some...
spheres”: Kistiakowsky (1980), p.
20.
2382.
“You don’t...
it”: interview with G.
B.
Kistiakowsky, Cambridge,
Mass., Jan.
15, 1982.
2383.
“e castings...
charge”: Bainbridge (1945), p.
39.
2384.
“at last...
life”: Badash (1980), p.
46.
2385.
“Very shortly...
hysteria”: JRO to ER, May 19, 1950.
JRO Papers,
Box 62.
2386.
nickel: Bill Jack Rodgers, LANL, personal communication.
2387.
“beautiful to...
threatened”: Smith (1954), p.
88.
2388.
“Right in...
this?”: quoted in Szasz (1984), p.
72.
2389.
“on the...
insignificant”: Bainbridge (1945), p.
39.
2390.
“when you...
rabbit”: Libby (1979), p.
171.
2391.
“We were...
way”: quoted in Johnson (1970), p.
11.
2392.
“e [high-...
mistake”: Wilson (1975), p.
185ff.
2393.
“So of...
me”: Badash (1980), p.
59.
2394.
“Everybody at...
work”: Kistiakowsky (1980), p.
21.
2395.
“a.
1 box...
bomb”: J.
A.
Derry to Adm.
W.
S.
DeLany, July 17,
1945.
MED 50.3 , Shipment of special materials (bomb).
2396.
“We drove...
dud”: Badash (1980), p.
75ff.
2397.
“His was...
him”: Bush (1970), p.
148.
2398.
“Sunday morning...
society”: Badash (1980), p.
59.
2399.
“What about...
whimsical”: quoted in Lamont (1965), p.
184.
2400.
“Gadget complete...
there?”: Bainbridge (1945), p.
43.
2401.
“in less...
sacrifices”: quoted in Szasz (1984), p.
75.
2402.
JRO climbed tower: Lamont puts this visit at 1600, when JRO was
in conference with Hubbard.
Lamont (1965), p.
190.
2403.
“Funny how...
work”: quoted in ibid., p.
193.
2404.
“I had...
possible”: Groves (1962), p.
296ff.
2405.
“thoughtless bravado”: Wilson (1975), p.
225.
2406.
“Trying to...
whiskey”: Teller (1979), p.
147.
2407.
“On the...
Zero”: Wilson (1975), p.
227.
2408.
“Soon aer...
tower”: ibid.
2409.
“the night...
seen”: Lawrence (1946), p.
5.
2410.
“It was...
Oppenheimer”: Else (1980).
2411.
0200 weather conference: details from Szasz (1984), p.
76ff., who
finds them in Hubbard’s contemporary journal.
2412.
“What the...
weather”: quoted in ibid., p.
76.
2413.
“or...
you”: quoted in ibid., p.
77.
2414.
“Sporadic rain...
tower”: Wilson (1975), p.
228.
2415.
“But my...
water”: Segrè (1970), p.
146.
2416.
“Hubbard gave...
= 0”: Wilson (1975), p.
228.
2417.
“I drove...
S 10,000”: ibid., p.
228ff.
2418.
“I unlocked...
5:09:45 a.m.”: ibid., p.
229.
2419.
“With the...
unendurable”: Lawrence (1946), p.
6.
2420.
“We were...
eye”: Teller (1962), p.
17.
2421.
“I wouldn’t...
lotion”: Teller (1979), p.
148.
2422.
“It was...
flash”: Lawrence (1946), p.
7.
2423.
“personally nervous...
fault”: MED 319.1 , Trinity test reports
(misc.).
2424.
“only of...
happened”: Groves (1962), p.
296.
2425.
“groups of...
point”: MED 319.1.
2426.
“Lord, these...
heart”: quoted in Lamont (1965), p.
226.
2427.
“e control...
safe)”: GBK to Richard Hewlett (n.d.), JRO Papers,
Box 43.
2428.
“I put...
point”: Teller (1979), p.
148.
2429.
“Dr.
Oppenheimer...
ahead”: quoted in Groves (1962), p.
436.
2430.
“I watched...
rise”: MED 319.1.
2431.
“but at...
excited!)”: ibid.
2432.
“Now the...
zero”: quoted in Giovannitti and Freed (1965), p.
196.
2433.
“the very...
distance”: Bethe (1964), p.
13.
2434.
“e shock...
center”: ibid.
2435.
“because higher...
maximum”: ibid., p.
14ff.
2436.
“any further...
seconds”: ibid., p.
92ff.
2437.
“e expansion...
screw”: Bainbridge (1945), p.
60.
2438.
“We were...
nature”: Rabi (1970), p.
138.
2439.
“was like...
sunlight”: Teller (1962), p.
17.
2440.
“We had...
back”: quoted in Los Alamos: beginning of an era 1943-
1945 (n.d.) (hereaer LABE), p.
52.
2441.
“Just as...
surprise”: MED 319.1.
2442.
“it looked...
seconds”: quoted in LABE, p.
53.
2443.
“At the...
breath-taking”: MED 319.1.
2444.
“e most...
possible”: Segrè (1970), p.
147.
2445.
“From ten...
sunrise”: quoted in Terkel (1984), p.
512ff.
2446.
“e flash...
yards”: D.
R.
Inglis, MED 319.1.
2447.
“Most experiences...
anybody”: quoted in LABE, p.
53.
2448.
“the overcast...
sunrise”: MED 319.1.
2449.
“the path...
clouds”: ibid.
2450.
“When the...
ball”: ibid.
2451.
“About 40...
T.N.T.”: ibid.
2452.
“From the...
measurement”: Segrè (1970), p.
147ff.
2453.
“He was...
noise”: L.
Fermi (1954), p.
239.
2454.
“And so...
worked”: Else (1980).
2455.
“No one...
display”: Wilson (1975), p.
230.
2456.
“personally thought...
it”: Groves (1962), p.
439.
2457.
“I slapped...
dollars”: Badash (1980), p.
60.
2458.
“It’s empty...
wait”: quoted in Lamont (1965), p.
237.
2459.
“I finished...
test”: Wilson (1975), p.
230.
2460.
“Our first...
worried”: quoted in Szasz (1984), p.
91.
2461.
“Naturally, we...
was”: Rabi (1970), p.
138.
2462.
“We waited...
another”: quoted in Giovannitti and Freed (1965),
p.
197.
2463.
“When it...
it”: Oppenheimer (1946), p.
265.
2464.
“He was...
it”: Else (1980).
2465.
“When Farrell...
you”: Groves (1962), p.
298.
2466.
“the best...
philosophy”: quoted in Davis (1968), p.
184.
2467.
“My faith...
restored”: quoted in Szasz (1984), p.
89.
2468.
21 KT, 18 KT: cf.
telephone notes of 7:55 A.M.
LRG to Jean O’Leary,
July 16, 1945.
MED 319.1.
2469.
18.6 KT: Bainbridge (1945), p.
67.
2470.
“For the...
driven”: L.
Fermi (1954), p.
238.
2471.
“You could...
future”: quoted in Szasz (1984), p.
91.
2472.
“Partially eviscerated...
permanently”: SW to LRG, July 21, 1945.
MED 4, Trinity test.
2473.
Frank Oppenheimer experiment: Bainbridge (1945), p.
48.
2474.
“He applied...
reality”: quoted in Terkel (1984), p.
513.
2475.
0836 PWT: Ethridge (1982), p.
81.
Chapter 19: Tongues of Fire
2476.
Kirkpatrick reported to Groves: cf.
handwritten reports dated
March 31, April 11, and May 10, 1945, at MED 5C, Preparation and
movement of personnel and equipment to Tinian.
2477.
“Tests showed...
carburetors”: Tibbets (1946), p.
133.
2478.
“e performance...
theater”: Ramsey (1946), p.
146.
2479.
eleven B-29’s: Peer DeSilva to John Lansdale, Jr., June 28, 1945.
MED 371.2.
2480.
“looked...
Paradise”: quoted in Craven and Cate (1958), V, p.
707.
2481.
“Tinian is...
landed”: Morrison (1946), p.
177.
2482.
“e first...
Tinian”: Ramsey (1946), p.
147.
2483.
“Jimmy...
Bible”: quoted in Messer (1982), p.
6.
2484.
“a warning...
capitulate”: Stimson and Bundy (1948), p.
621.
2485.
“from the...
Department”: quoted in Giovannitti and Freed
(1965), p.
180.
2486.
“Secretary Byrnes...
there?”: quoted in ibid.
2487.
“We reviewed...
knows?”: Ferrell (1980), p.
41.
2488.
“Proposed Program for Japan”: cf.
Stimson and Bundy (1948), p.
620ff.
2489.
“the statement...
Japan”: quoted in Giovannitti and Freed (1965),
p.
185.
2490.
“e foreign...
concerned”: quoted in Feis (1966), p.
67.
2491.
“It is...
homeland”: quoted in ibid., p.
68.
2492.
“terrible political...
war?”: quoted in Giovannitti and Freed
(1965), p.
203.
2493.
“Operated on...
posted”: MED 5E, Terminal cables.
2494.
“Well...
Leavenworth”: quoted in Bundy (1957), p.
57.
2495.
“e following...
Emperor”: quoted in Giovannitti and Freed
(1965), p.
203.
2496.
“Neither the...
test”: quoted in ibid.
2497.
a year’s supply of ammunition: production, that is, “which is
estimated to equal 350 division months of defensive fighting from
fixed positions.” Effects of Strategic Bombing (n.d.), cover
memorandum dated July 25, 1945, p.
5.
MED 319.2 , Misc.
2498.
“Subject to...
government”: quoted in Feis (1966), p.
81.
2499.
“all your...
city”: MED 5E.
2500.
“aware of...
it”: ibid.
2501.
“If any...
rapidly”: ibid.
2502.
“the imminence...
August”: ibid.
2503.
Groves’ narrative: cf.
Groves (1962), p.
433ff.
2504.
“tremendously pepped...
confidence”: quoted in Feis (1966), p.
85.
2505.
October 1: Arnold (1949), p.
564.
2506.
“In order...
cities”: ibid.
2507.
fiy-eight cities: Overy (1980), p.
100.
2508.
“practically identical...
out”: quoted in Wölk (1975), p.
60.
2509.
“We regarded...
lives”: quoted in Mosley (1982), p.
337ff.
2510.
“We’d had...
dropped”: quoted in “Ike on Ike,” Newsweek, Nov.
11, 1963, p.
108.
2511.
“Doctor has...
farm”: MED 5E.
2512.
“e cable...
problem”: “Ike on Ike.”
2513.
“Believe Japs...
homeland”: Ferrell (1980), p.
42.
2514.
“Operation may...
10”: MED 5E.
2515.
“always...
authority”: ibid.
2516.
“Hiroshima...
here”: ibid.
2517.
Official Air Force historians: i.e., Craven and Cate (1958), V; cf.
p.
710.
2518.
“First one...
sound”: MED 5E.
2519.
“As a...
once”: Feis (1966), p.
101.
2520.
Stalin knew of Trinity: according to a secret U.S.
intelligence
agency history of the Soviet atomic bomb program reported in Szulc
(1984), p.
3.
2521.
“I casually...
Japanese”: Truman (1955), p.
416.
2522.
“at...
far”: Oppenheimer (1963), III (Los Alamos version), p.
16.
2523.
“We have...
useful”: Ferrell (1980), p.
42.
2524.
the historic directive: WAR 37683, MED 5E.
2525.
“in order...
possible”: ibid.
2526.
C-54’s: cf.
J.
A.
Derry to Adm.
W.S.
DeLany, Aug.
17, 1945.
MED
5C.
2527.
Potsdam Declaration: cf.
Truman (1955), p.
390ff.
2528.
“We faced...
Declaration”: Byrnes (1947), p.
262.
2529.
Japanese response: this discussion follows Feis (1966), p.
107ff.
2530.
“I believe...
war”: quoted in ibid., p.
109ff.
2531.
“In the...
weapon”: Stimson and Bundy (1948), p.
625.
2532.
three B-29’s: J.
A.
Derry to Adm.
W.
S.
DeLany, Aug.
17, 1945.
2533.
Indianapolis: cf.
esp.
Ethridge (1982).
2534.
“I took...
more”: Hashimoto (1954), p.
224.
2535.
“ose who...
drowned”: quoted in Ethridge (1982), p.
89.
2536.
“We...
men”: quoted in ibid.
2537.
“so sweet...
life”: quoted in ibid., p.
92.
2538.
“at length...
tinned)”: Hashimoto (1954), p.
226.
2539.
HIROSHIMA...
THEM: MED 5B.
2540.
“My chief...
face”: Stimson and Bundy (1948), p.
632.
2541.
“our obligation...
use”: cf.
report at MED 76.
2542.
“badly...
equalizer”: quoted in Giovannitti and Freed (1965), p.
237.
2543.
“First of...
thing”: ET to LS, July 2, 1945.
MED 201, Leo Szilard.
2544.
“To avert...
deliverance”: Churchill (1953), p.
639.
2545.
“It was...
end”: Anscombe (1981), p.
64.
2546.
“It was...
people”: Moyers (1984).
2547.
“impatience to...
ordeal”: Feis (1966), p.
120.
2548.
A JAP BURNS: Life, Aug.
13, 1945, p.
34.
is issue appeared on Aug.
6, postdated as is customary to extend newsstand life.
Luis Alvarez
suggested to me this exercise in examining the popular mood.
2549.
cordite charge: not, as some have written mistakenly, its bullet.
Cf.
“Check list for loading charge in plane....” MED 5B.
2550.
precaution prepared at Los Alamos: cf.
Hawkins (1947), p.
225.
2551.
orders to bring bomb back: Craven and Cate (1958), V, p.
716.
2552.
“With the...
completed”: Ramsey (1946), p.
149.
2553.
Farrell telexed Groves: Feis (1966), p.
114.
2554.
August 2: J.
A.
Derry to Adm.
W.
S.
DeLany, Aug.
7, 1945.
2555.
one Fat Man for drop test: cf.
Ramsey (1946), p.
150.
2556.
“By August...
busy”: Tibbets (1973), p.
55.
2557.
Spitzer diary: quoted in omas and Witts (1977).
2558.
“At 1400...
6”: Ramsey (1946), p.
151.
2559.
bomb-loading procedure: cf.
Harold S.
Gladwin, Jr., to Boeing
Service Dept., Eng.
Div., Aug.
20, 1945.
MED 5B.
2560.
“an elongated...
fins”: Jacob Beser, quoted in omas and Witts
(1977), p.
216.
2561.
“is radar...
altitude”: Hawkins (1947), p.
225ff.
2562.
“e operation...
it”: H.
S.
Gladwin, Jr., to Boeing Service Dept., Aug.
20, 1945.
2563.
“rough the...
paper”: quoted in Marx (1967), p.
98ff.
2564.
“paint that...
big”: quoted in omas and Witts (1977), p.
232.
2565.
“What...
plane?”; quoted in ibid., p.
233.
2566.
“By dinnertime...
poker”: Tibbets (1946), p.
135.
2567.
“Final...
6”: Ramsey (1946), p.
151.
2568.
“to be...
enemies”: quoted in omas and Witts (1977), p.
237.
2569.
“amid...
premiere)”: Ramsey (1946), p.
151.
2570.
“It was...
ready”: Tibbets (1946), p.
135.
2571.
“e B-29...
airborne”: ibid.
2572.
course, altitude, etc.: cf.
navigator’s charts printed as end papers to
Marx (1967).
2573.
cordite loading: cf.
“Check list for loading charge in plane....”
MED 5B.
For times cf.
Parson’s log at Cave Brown and MacDonald
(1977), p.
522ff.
2574.
“At forty-...
runs”: quoted in Lawrence (1946), p.
220.
2575.
“e colonel...
‘George’ ”: quoted in variant forms in Marx
(1967), p.
78, and Lawrence (1946), p.
220.
2576.
“A chemist’s...
guess”: quoted in Marx (1967), p.
106, and
Lawrence (1946), p.
220ff.
2577.
“Attention!...
puzzle”: quoted in Talk of the Town (1946), p.
16.
2578.
“At 4:30...
spell”: quoted in Lawrence (1946), p.
220.
2579.
“Aer leaving...
Away”: quoted in ibid.
and in Marx (1967), p.
135ff.
2580.
“e bomb...
Tinian”: quoted in Marx (1967), p.
136.
2581.
“Well...
now”: quoted in Lawrence (1946), p.
221.
2582.
“Our primary...
Hiroshima”: quoted in ibid.
2583.
“It’s Hiroshima”: quoted in Marx (1967), p.
143.
2584.
“As we...
target”: quoted ibid., p.
157.
2585.
“Twelve miles...
plane”: Tibbets (1946), p.
136.
2586.
perfect aiming point: omas and Witts (1977), p.
220.
2587.
“Ferebee had...
goes”: Tibbets (1946), p.
136.
2588.
“e radio...
lead”: ibid.
2589.
“Fellows...
history”: according to Jacob Beser, quoted in Marx
(1967), p.
173.
2590.
“[It was]...
plane”: quoted in Giovannitti and Freed (1965), p.
250.
2591.
“I don’t...
mountains”: quoted in ibid.
2592.
“If you...
home”: quoted in ibid.
2593.
“I kept...
smoke”: quoted in Marx (1967), p.
171 ff.
2594.
“at city...
me”: quoted in ibid., p.
174.
2595.
8:16:02: cf.
e Committee for the Compilation of Materials on
Damage Caused by the Atomic Bombs in Hiroshima and Nagasaki
(1981)—hereaer cited as Committee—p.
21.
All statistics from this
source unless otherwise indicated.
e official time according to
Hiroshima City is 8:15.
2596.
“It...
impersonal”: Tibbets (1973), p.
55.
2597.
“If I...
mind”: quoted in Marx (1967), p.
221.
2598.
Hiroshima: cf.
in particular Cave Brown and MacDonald (1977);
Committee (1981); Hachiya (1955); Liebow et al.
(1949); Liebow
(1965); Lion (1967); NHK (1977); Osada (1982); USSBS (1976), X.
2599.
Hiroshima history: cf.
Kosaki (1980).
2600.
“Hiroshima was...
harbor”: Cave Brown and MacDonald (1977),
p.
554.
2601.
“e hour...
garden”: Hachiya (1955), p.
1.
2602.
“Just as...
leaves”: Osada (1982), p.
8.
2603.
“Shortly aer...
delirium”: ibid., p.
305.
2604.
“Accompanying the...
explosion”: Liebow (1965), p.
68.
2605.
“Because the...
miles]”: Cave Brown and MacDonald (1977), p.
570.
2606.
“e temperature...
life”: Committee (1977), p.
119.
2607.
“severe thermal...
viscerae”: ibid.
2608.
“Doctor...
he?”: Hachiya (1955), p.
92.
2609.
“e inundation...
fatalities”: Lion (1967), p.
21.
2610.
“ere was...
dead”: quoted in ibid., p.
27.
2611.
“I asked...
impossible”: Hachiya (1955), p.
114.
2612.
“Father Kopp...
hand”: Cave Brown and MacDonald (1977), p.
542.
2613.
“Ah, that...
around”: Osada (1982), p.
352.
2614.
“e vicinity...
arms”: ibid., p.
305.
2615.
“at boy...
that”: ibid., p.
194.
2616.
“My body...
ending’ ”: quoted in Lion (1967), p.
22.
2617.
“I just...
world”: quoted in ibid., p.
23.
2618.
“Within the...
sound”: Hachiya (1955), p.
164.
2619.
“When I...
ruins”: Osada (1982), p.
224.
2620.
“e shortest...
hysterically”: Hachiya (1955), p.
2.
2621.
“e appearance...
them”: quoted in Lion (1967), p.
27.
2622.
“I heard...
burned”: NHK (1977), p.
12ff.
2623.
“On both...
sleepwalkers”: Osada (1982), p.
313.
2624.
“Everything I...
about”: quoted in Lion (1967), p.
29.
2625.
“at day...
rags”: Osada (1982), p.
10.
2626.
“e people...
them”: ibid., p.
258.
2627.
“People came...
sight”: ibid., p.
97.
2628.
“e flames...
looks”: ibid., p.
234.
2629.
“Screaming children...
blood”: ibid., p.
305.
2630.
“It was...
flames”: Liebow et al.
(1949), p.
856ff.
2631.
“e whole...
alive”: Osada (1982), p.
8ff.
2632.
“I really...
walking”: ibid., p.
65ff.
2633.
“I was...
her”: ibid., p.
122ff.
2634.
“I le...
her”: quoted in Lion (1967), p.
40.
2635.
“Beneath the...
flames”: Cave Brown and MacDonald (1977), p.
544.
2636.
“I was...
thing”: Osada (1982), p.
137ff.
2637.
“A woman...
help”: NHK (1977), p.
49.
2638.
“ere were...
up”: Osada (1982), p.
43.
2639.
“Nearby...
trousers”: ibid., p.
364.
2640.
“I walked...
felt”: quoted in Lion (1967), p.
50.
2641.
“I was...
striking”: NHK (1977), p.
39.
2642.
“a man...
ankles”: quoted in Mary McGrory, “Hiroshima Horrors
Relived,” Kansas City Times, March 24, 1982.
p.
A13.
2643.
“A man...
up”: quoted in Lion (1967), p.
42.
2644.
“In front...
blackness”: quoted in ibid., p.
49ff.
2645.
“e corpse...
hand”: NHK (1977), p.
96.
2646.
“ere was...
blindly”: Osada (1982), p.
154.
2647.
“I saw...
be?”: NHK (1977), p.
52.
2648.
“A streetcar...
tremble”: Osada (1982), p.
55.
2649.
“e more...
get”: ibid., p.
77.
2650.
“Since just...
having”: ibid., p.
83.
2651.
“I went...
eyes”: quoted in Lion (1967), p.
36.
2652.
“I and...
agonies”: Osada (1982), p.
230.
2653.
“At the...
help”: ibid., p.
352ff.
2654.
“Near the...
Hell”: ibid., p.
79ff.
2655.
“We came...
flame”: ibid., p.
62.
2656.
“e fire...
heads”: ibid., p.
72.
2657.
“I had...
faces”: ibid., p.
237.
2658.
“Between the...
water”: Hachiya (1955), p.
19.
2659.
“While taking...
him”: NHK (1977), p.
48.
2660.
“ere were...
me”: Hachiya (1955), p.
101.
2661.
“Men whose...
sea”: Osada (1982), p.
178.
2662.
“We...
around”: ibid., p.
94.
2663.
“Bloated corpses...
earth”: ibid., p.
334.
2664.
“I had...
shore”: quoted in Trumbull (1957), p.
76.
2665.
“I got...
place”: Osada (1982), p.
173.
2666.
“e river...
terrible”: ibid., p.
219.
2667.
“ere was...
back”: Hachiya (1955), p.
15.
2668.
“Hundreds of...
drowned”: ibid., p.
77ff.
2669.
“Along the...
walk”: ibid., p.
184.
2670.
“Night came...
heaven”: NHK (1977), p.
44.
2671.
“Everybody in...
legs”: Osada (1982), p.
280.
2672.
“If you...
burns”: ibid., p.
99ff.
2673.
“Hiroshima...
land”: ibid., p.
54.
2674.
“e bright...
collapse”: Cave Brown and MacDonald (1977), p.
546.
2675.
“e streets...
height”: Hachiya (1955), p.
8.
2676.
“Nothing...
view”: ibid., p.
31.
2677.
“I climbed...
exist”: quoted in Lion (1967), p.
29.
2678.
“I reached...
heart”: quoted in ibid., p.
86.
2679.
“It is...
instantaneously”: Committee (1977), p.
61.
2680.
“In Hiroshima...
destroyed”: ibid., p.
379.
2681.
“[She was]...
child”: NHK (1977), p.
70.
2682.
“We gathered...
out”: interview with Sakae Itoh, Hiroshima, Aug.
5, 1982.
2683.
“Aer a...
mouths”: Hachiya (1955), p.
164.
2684.
“On the...
mountain”: Osada (1982), p.
72ff.
2685.
“Towards evening...
Hiroshima”: Hachiya (1955), p.
32.
2686.
“Survivors began...
death”: Lion (1967), p.
57.
2687.
“atomic bomb...
irradiation”: Committee (1977), p.
115.
2688.
“Following the...
recover”: Hachiya (1955), p.
97.
2689.
gamma radiation: cf.
Hempelmann et al.
(1952), p.
286ff.
2690.
anti-clotting factor: cf.
Liebow et al.
(1949), p.
927.
2691.
“Hemorrhage was...
cases”: Hachiya (1955), p.
147ff.
2692.
“found...
autopsied”: ibid., p.
145.
2693.
“evidence of...
eye”: Liebow et al.
(1949), p.
923.
2694.
“the bodies...
living”: quoted in Lion (1967), p.
66.
2695.
“We were...
cancer”: quoted in ibid., p.
61.
2696.
“Mother was...
cry”: Osada (1982), p.
227.
2697.
“in the...
instant”: Committee (1977), p.
6.
2698.
“e whole...
foundations”: ibid., p.
336.
2699.
“Such a...
nothing”: quoted in Lion (1967), p.
79.
2700.
“the total...
dead”: quoted in Liebow (1965), p.
82.
2701.
“How many...
explosion”: Cave Brown and MacDonald (1977), p.
549.
2702.
Standardized Casualty Rate: cf.
Liebow (1965), p.
235.
2703.
“ose scientists...
it?”: Osada (1982), p.
264.
2704.
“is is...
home”: Truman (1955), p.
421.
2705.
“Gen G...
time”: Aug.
6, 1945, transcript, MED 201, Groves, L.
R.,
telephone conversations.
2706.
“e greatest...
earth”: quoted in Truman (1955), p.
422.
2707.
“I suppose...
on”: LS to GW, Aug.
6, 1945.
Egon Weiss, personal
communication.
2708.
“At first...
asleep”: Hahn (1970), p.
170.
2709.
“en one...
enemies”: Frisch (1979), p.
176.
2710.
“the importance...
all”: “From the Rubble of Okinawa: A Different
View of Hiroshima.” Kansas City Star, Aug.
30, 1981, p.
II.
2711.
propaganda effort: cf.
J.
F.
Moynahan to L.
R.
Groves, May 23,
1946.
MED 314.7 , History.
2712.
“What we...
longer”: quoted in Mosley (1982), p.
340.
2713.
“a certain...
airplane”: J.
F.
Moynahan to L.
R.
Groves, May 23,
1946.
2714.
“the equivalent...
weapons”: ibid.
2715.
Nagasaki leaflets: ibid.
2716.
“was originally...
schedule”: Ramsey (1946), p.
153.
2717.
“With the...
orders”: O’Keefe (1983), p.
97.
2718.
“When I...
backward”: ibid., p.
98.
2719.
“nothing that...
resolder them”: ibid., p.
99.
2720.
“My mind...
finished”: ibid., p.
100ff.
2721.
0347: Ramsey (1946), p.
154.
2722.
“e night...
us”: Cave Brown and MacDonald (1977), p.
557.
2723.
Ashworth changed plugs: cf.
his log at Ramsey (1946), p.
154.
2724.
“Two...
seen”: quoted in ibid., p.
155.
2725.
“the Japs...
ocean”: quoted in Marx (1967), p.
202.
2726.
“A smell...
gates”: William C.
Bryson, Capt., USN, Sept.
14, 1945.
Bul.
Atom.
Sci.
Dec.
82, p.
35.
2727.
surrender offer: this discussion relies in part on Bernstein (1977).
2728.
“does not...
Ruler”: quoted in Butow (1954), p.
244.
2729.
“taking a...
hands”: quoted in Bernstein (1977), p.
5.
2730.
“I cannot...
war”: quoted in ibid., p.
6.
2731.
“crucifixion...
President”: quoted in ibid., p.
5.
2732.
“willingness to...
accomplished”: quoted in ibid., p.
6ff.
2733.
“From the...
people”: quoted in Feis (1966), p.
134.
2734.
“We would...
bomb”: quoted in Bernstein (1977), p.
9.
2735.
“Truman said...
kids”: quoted in Herken (1980), p.
11.
2736.
“Provided there...
August”: LRG to Chief of Staff, Aug.
10, 1945.
MED 5B.
2737.
“It was...
now?”: quoted in Scott-Stokes (1974), p.
109.
2738.
“placing...
officials”: quoted in Bernstein (1977), p.
13.
2739.
“I have...
unusual”: quoted in ibid., p.
15ff.
2740.
“a plan...
attack”: quoted in Feis (1966), p.
205.
2741.
“evidence of...
ancestors?”: quoted in ibid., p.
208.
2742.
“the...
placed”: quoted in Bernstein (1977), p.
13.
2743.
“Flash!...
soon”: quoted in Feis (1966), p.
209n.
2744.
“Despite the...
generation”: quoted in ibid., p.
248.
2745.
“If it...
mad”: quoted in Scott-Stokes (1974), p.
109.
2746.
“An atomic...
slaughter”: Committee (1977), p.
335.
2747.
“By the...
identity”: Elliot (1972), p.
138ff.
2748.
“e experience...
mankind”: Committee (1977), p.
340.
2749.
“e night...
pounding”: Hachiya (1955), p.
114ff.
1 Nagaoka indicates indirectly that the visit took place sometime prior to July 1910—aer Marsden’s 1909 discovery and before Rutherford’s announcement to Geiger at Christmastime 1910
that he had worked out an explanation.
1 George Gamow had proposed such a model in Copenhagen in 1928.
Bohr credited it to Gamow
at the October 1933 Solvay conference, as did Heisenberg.
Bohr and his student Fritz Kalkar
subsequently developed the model and physicists customarily attribute it to him.
1 Fractionation—fractional crystallization—was a technique of chemical analysis pioneered by Marie Curie in the course of purifying polonium and radium.
Most substances are more soluble at a
high temperature than a low.
Make a strong boiling solution of a substance—for rock candy, for
example, sugar in water—cool the solution, and at some point the substance will emerge out of
solution to form pure crystals.
Fractional crystallization further involves separating out of the same
solution several different, chemically similar substances by taking advantage of their tendency to
crystallize at different temperatures according to differences in their atomic weights, lighter elements
crystallizing first.
1 e distinction between U235 and U238 had already fired a debate.
“Fermi and a number of others,” says John Dunning, “had considerable doubts about U-235 or even disagreed—they thought it
was U-238 [that was responsible for slow-neutron fission].” e disagreement incensed Bohr, who told
Lèon Rosenfeld he was “outraged” that Fermi should question the logic of his argument that thorium
and U238 stood on one side and U235 on the other.
1106 “It was both the strength and the weakness of Fermi,” writes Rosenfeld, “to be so intent on following his own lines of thought that he was
impervious to any outside influence....
He fancied there could be a different interpretation of the
evidence discussed by Bohr, and that only experiment could decide.” Dunning, on the other hand,
“immediately accepted Bohr’s argument.” 1107 e important outcome was that Dunning began to think of isotope separation, while Fermi continued to pursue the possibility of a chain reaction in natural uranium.
With unusual and uncharacteristically Fermian conservatism, so did Szilard.
1 Although Bohr had speculated many years earlier that the transuranic elements, if any, would probably be chemically similar to uranium, researchers still commonly assumed that the transuranics
would be chemically similar to the series of metals in the periodic table that begins with rhenium and
osmium and includes platinum and gold.
“Eka” is an old prefix meaning “beyond.”
1 Compton’s memory errs toward more optimism than Fermi’s calculations warranted.
Aer Compton’s visit Gregory Breit, Briggs’ theoretician on the Uranium Committee, asked Fermi to work
his formulae on paper.
Fermi was busy with his uranium-graphite experiment and produced, on
October 6, a sketchy set of notes.
He guessed at the cross sections and came up with 130,000 grams—
287 pounds.
“One cannot,” he added, “in my opinion, exclude the possibility that [the critical mass]
may be as low as 20,000 grams [44 pounds] or as high as one or more tons.” 1486
1 e proximity fuse was a miniature radar unit shaped to replace the ballistic nose of anti-aircra
shells.
It sensed its proximity to a target—an enemy plane—and exploded the shell it rode at a preset
range, oen turning a miss into a kill.
Its development was another of Bush’s responsibilities and it was
one of science’s most important contributions to the war.
Merle Tuve, Richard Roberts1108 and most of the physics team at the Department of Terrestrial Magnetism of the Carnegie Institution had turned
from fission research in August 1940 to develop it.1842
1 Spontaneous fission, a relatively rare nuclear event, differs from fission caused by neutron bombardment; it occurs without outside stimulus as a natural consequence of the instability of heavy nuclei.
1 A betatron accelerates electrons to high speeds in a magnetic field; such beta ray-like electrons can then be directed onto a target to produce intense beams of high-energy X rays.
1 “e glory is departed.”
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