For a few years, I belonged to a history book club. Unlike many book clubs, we didn’t all read the same book. Instead, we’d pick a topic for the next meeting, at which the participants would each give short presentations on books of their choosing.
Recently I ran across my write-ups. As the internet has yet to run out of space, I thought I’d post them. I begin with two on the atomic bomb.
(Why ‘atomic bomb’, rather than ‘nuclear bomb’? See this post.)
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
Richard Rhodes’ The Making of the Atomic Bomb has been called a tour de force, a magnum opus, and by one Nobel laureate who worked on the Manhattan project, “an epic worthy of Milton”. It is all that, but also it’s compulsively readable. From the plethora of anecdotes, let me select just a few.
In 1939, the first meeting of the Advisory Committee on Uranium took place, one of the immediate consequences of the famous Einstein letter to Roosevelt. Teller requested a modest sum of $6000 from the Army for research purposes; the Army representative responded with a 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. Then 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.
“All right, all right,” the [Army rep] snapped, “you’ll get your money.”
By 1942, Fermi’s group at the University of Chicago was constructing experimental reactors, as yet subcritical. Fermi wanted to build the first supercritial chain-reaction in the squash court under the west stands. Arthur Compton, in charge, gave the go ahead without informing the president of the University. He reasoned that he should not ask a lawyer to judge a matter of nuclear physics. “The only answer he could have given would have been no. And this answer would have been wrong. So I assumed the responsibility myself.”
Of course, Fermi included multiple safe-guards. In addition to two automatic mechanisms, he had a control rod suspended above the reactor by a rope, and a physicist, feeling foolish, standing by to chop the rope with an ax if all else failed.
April 1943 saw the inauguration of bomb design at Los Alamos. One design had a kind of cannon shoot a uranium bullet into a uranium target. Problem: the assembly would be way too heavy for any airplane to carry. They finally realized that a standard cannon must be sturdy enough to withstand repeated firings, not a consideration for the A-bomb.
The other, more sophisticated design used implosion, symmetrically squeezing a plutonium core to criticality. At one review session, one physicist [Feynman] voiced his skepticism ironically:
With everyone grinding away in such dead earnest here, 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. The point to watch for is whether he can blow in a beer can without splattering the beer.
Oppenheimer recalled a conversation with Fermi: “After he had sat in on one of his first conferences here, he turned to me and said, ‘I believe your people actually want to make a bomb.’ I remember his voice sounded surprised.”
Fermi took up fishing:
but he went about it in a peculiar way. … 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. His student made a point of reviewing the subtleties of trout fishing with his old friend. “Oh, I see,” Fermi countered, “it is a battle of wits.”
Electromagnetic separation required miles of wires. Copper being in short supply, the Treasury offered to provide silver. General Groves took them up on the offer, requesting between five and ten thousand tons of silver. This led to the icy reply: “In the Treasury we do not speak of tons of silver; our unit is the Troy ounce.”
At Hanford, Washington, one physicist remembers when the plutonium separation facilities started to operate: “great plumes of brown fumes blossomed above the concrete canyons, climbed thousands of feet into the air, and drifted sideways as they cooled, blown by winds aloft.”
Niels Bohr had discounted the possibility of atomic bombs, because of the difficulty of enriching uranium. “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.’ ”
As Rhodes puts it:
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.
Finally, a quote from Henry Stimson, Secretary of War under Roosevelt and Truman: “The 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.”
Diagonal Argument 