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Hooper gathered a group of officers and navy civilian scientists. For the next hour Fermi outlined the military potential of fission in his halting English with a thick Italian accent. His audience listened politely as they tried to follow along. Few if any knew what a neutron was, and little came of the meeting. When it was over, Admiral Hooper merely asked to be kept informed. No sooner had Fermi left than a navy scientist who had attended the briefing called another and asked him, “Who is this Fermi? Is he a Fascist or what?” 13 Such was the outcome of the first contact between physicists and the government on the possibility of an atomic bomb.
Fermi rendezvoused with Szilard and Teller in Washington that weekend. The navy’s indifference to the dangers and opportunities of fission frustrated and infuriated them. “If we brought a bomb to them all ready made on a silver platter,” said Fermi bitterly, “there would still be a 50/50 chance that they would mess it up.” 14 They were apprehensive. They had inside knowledge of German science, and much respect for it, even though many of Germany’s best physicists had been driven away. There was still enough scientific talent in Germany, they felt, to solve the problem of a fission bomb. German physicists had read the scientific literature about fission and a chain reaction, as they had. Heisenberg had mentioned his interest in uranium on a recent tour of American universities. While some, like Bohr, found the idea of an atomic bomb scarcely credible because of the isotope-separation problem, Szilard, Teller, and Fermi had little doubt that such a bomb could be made. And if such a bomb could be made, they reasoned, then one would be made. The prospect of such a weapon in Hitler’s hands meant nothing short of doom.
Their experience with the Navy Department led them to conclude that ideas presented at a low level of the governmental bureaucracy were likely to go nowhere, but those inserted at the top stood a much better chance of producing results. The White House was more likely to be open to new ideas than would unimaginative bureaucrats. 15 Roosevelt had to be warned, but how? What could they do? They were well known in physics circles, but nothing more than registered aliens in American society at large. As newcomers to the United States, they lacked the political connections necessary to press their claims effectively in the corridors of power.
Then Szilard thought of his teacher and friend Albert Einstein. A letter from a scientist of Einstein’s stature might make the president sit up and take notice. Szilard contacted Einstein and explained the situation. An avowed pacifist, Einstein agonized at the thought of setting in motion a program to build an atomic bomb, so antithetical to his instincts. Einstein struggled with his conscience for some time before finally concluding that bitter necessity required the United States to pursue a bomb—the Nazis must not get it first. Finally, in late July Einstein agreed to sound the alarm on Szilard’s behalf. It was unusual for a scientist of Einstein’s stature to take such a step. “The one thing most scientists are really afraid of is to make a fool of themselves,” Szilard said later, reflecting on Einstein’s decision. “Einstein was free from such a fear and this above all is what made his position unique on this occasion.” 16
On August second Szilard set out for Einstein’s summer retreat on Long Island with a letter he had drafted for Einstein’s signature. Szilard had never learned to drive, so he enlisted Teller, who was teaching physics at Columbia that summer, to take him out there. It was already hot and humid when Teller picked up Szilard outside the King’s Crown Hotel early in the morning and drove out to Long Island. “I entered history as Szilard’s chauffeur,” Teller later said. 17
Szilard and Teller knew Einstein’s general whereabouts, but not his specific address. Once they reached the north shore of Long Island, they began asking directions to the home of the famous Professor Einstein, but no one could help. Finally they asked a little girl with long braids who said she had never heard of Professor Einstein, but she knew where a nice old man with long white hair lived.
Szilard and Teller reached Einstein’s cottage on Peconic Bay in the late afternoon. They found the great man with a massive forehead and an aureole of white hair dressed in an old robe and slippers sitting in the living room, empty except for a few garden chairs and a small table, pondering physics. A picture window looked out on to Long Island Sound, but the shutters were half closed to keep out the heat. Looking like an old-fashioned Swiss watchmaker in a small town who collected butterflies on Sundays, Einstein served his guests iced tea with heavily muscled arms and drank some himself while he reviewed the letter Szilard had drafted for him. His large bulging chocolate eyes followed the text carefully. In it, the physicist who had risked his life during World War I for his outspoken pacifist beliefs said that an atomic bomb might be possible and that the United States should speed up experiments regarding a uranium chain reaction. Szilard and Teller watched silently as Einstein hunched over the dining-room table and signed the letter:
Old Grove Road
Nassau Point
Peconic, Long Island
August 2, 1939
F. D. Roosevelt
President of the United States
White House
Washington, D.C.
Sir:
Some recent work by E. Fermi and L. Szilard, which has been communicated to me in manuscript, leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. Certain aspects of the situation which has arisen seem to call for watchfulness and, if necessary, quick action on the part of the Administration. I believe, therefore, that it is my duty to bring to your attention the following facts and recommendations:
In the course of the last four months it has been made probable—through the work of Joliot in France as well as Fermi and Szilard in America—that it may become possible to set up a nuclear chain reaction in a large mass of uranium, by which vast amounts of power and large quantities of new radium-like elements would be generated. Now it appears almost certain that this could be achieved in the immediate future.
This new phenomenon would also lead to the construction of bombs, and it is conceivable—though much less certain—that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat and exploded in a port, might very well destroy the whole port together with some of the surrounding territory. However, such bombs might very well prove to be too heavy for transportation by air.
The United States has only very poor ores of uranium in moderate quantities. There is some good ore in Canada and the former Czechoslovakia, while the most important source of uranium is the Belgian Congo.
In view of this situation you may think it desirable to have some permanent contact maintained between the Administration and the group of physicists working on chain reaction in America. One possible way of achieving this might be for you to entrust with this task a person who has your confidence and who could perhaps serve in an unofficial capacity. His task might comprise the following:
a) to approach Government departments, keep them informed of the further development, and put forward recommendations for Government action, giving particular attention to the problem of securing a supply of uranium ore for the United States;
b) to speed up the experimental work which is at present being carried on within the limits of the budgets of university laboratories, by providing funds if such be required, through his contacts with private persons who are willing to make contributions for this cause, and perhaps also by obtaining the cooperation of industrial laboratories which have the necessary equipment.
I understand that Germany has actually stopped the sale of uranium from the Czechoslovakian mines which she has taken over. That she should have taken such early action might perhaps be understood on the ground that the son of the German Under-Secretary of State, von Weizsäcker, is attached to the Kaiser-Wilhelm-Institute in Berlin where some of the American work on uranium is now being repeated.
Yours very truly,
Albert Einstein 18
After Szi
lard returned to New York, he began to think about how to get Einstein’s letter to the president. Through a friend, Gustav Stolper, an economist and former member of the German Reichstag who was now a refugee living in New York, Szilard made contact with Alexander Sachs—a Russian émigré, science buff, financier, and well-connected New Dealer with access to the White House. Sachs was an ideal go-between. He understood the concept of fission and the seriousness of what Szilard told him. Sachs agreed to get the letter to Roosevelt.
Events delayed Sachs’s meeting with the president. On August twenty-third Hitler and Stalin, ideological enemies but totalitarian twins, signed a cynical “nonaggression” pact that stunned the world and prepared to carve up Poland between them. On September first German tanks crashed into Poland, facing little more than horse cavalry as opposition. The years of threat and bluster and tension were over. World War II had begun. A Polish refugee in America who heard the news on the radio captured the feelings of a whole generation when he said, “I suddenly felt as if a curtain had fallen on my past life, cutting it off from my future. There has been a different color and meaning to everything ever since.” 19
By early October, Szilard had almost given up on Sachs. To Einstein he wrote: “There 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. I have decided to accord Sachs ten days’ grace.” 20 On October eleventh Sachs finally got his appointment with the president, more than two months after Einstein had signed Szilard’s letter and six weeks after the war had begun. Reminding FDR that Napoleon had missed the greatest technological marvel of his day when he rejected Robert Fulton’s offer to build a fleet of steamships, Sachs tendered Einstein’s letter and proceeded to explain the military potential of fission. Einstein had, of course, closed his appeal to the president with a warning that Germany had stopped the sale of uranium from mines in Nazi-controlled Czechoslovakia, one of the world’s few sources of the metal, a sure tip-off that Hitler was already at work on an atomic bomb. FDR quickly grasped the point. “Alex,” he said, “what you are after is to see that the Nazis don’t blow us up.” The president called in General Edwin “Pa” Watson, his personal aide, and told him, “This requires action.” 21
At Roosevelt’s request, Watson directed the creation of an Advisory Committee on Uranium to explore the feasibility of an American atomic bomb program and report its findings to the president. Lyman Briggs, the director of the National Bureau of Standards, was appointed the committee’s chairman. Although Briggs was a physicist, his interests and experience were not in nuclear physics. Moreover, he was conservative by nature, accustomed to operating—as most bureaucrats do—in a slow, cautious, and methodical manner. For Briggs, fission’s possibilities had to be soberly measured against opportunities in other fields. 22
The Uranium Committee met for the first time on October 21, 1939—ten long months after the discovery of fission in Germany. Sachs saw to it that Szilard and Teller were invited to the meeting. Fermi was also invited, but he refused to attend; his experience with Admiral Hooper and the navy made him unenthusiastic about another meeting with government bureaucrats. Fermi did, however, authorize Teller to speak on his behalf.
Szilard opened the meeting by emphasizing the possibility of creating a chain reaction in a uranium-graphite “pile” (or nuclear reactor). He explained to the committee that each time a uranium nucleus split apart, it released tremendous energy. But fission would not occur if one had to keep firing neutrons from an external source at the uranium atoms to break them up. If, on the other hand, the uranium atom released neutrons as it split, then these neutrons could go on and break up other nuclei. The neutrons from these disintegrations would trigger more, producing a chain of fissions. But neutrons had a less than 1 percent chance of fissioning a nucleus of natural uranium—thus no chance for a chain reaction. Neutrons needed to be slowed down. Slow neutrons had a more than 50 percent chance of fissioning a uranium nucleus—thus producing a chain reaction. The best way to slow neutrons was to use a “moderator,” which absorbed neutrons. The best moderator was graphite, whose carbon molecules absorbed about 10 percent of neutrons.
All of this sounded terribly exotic to the bureaucrats gathered around the table. The ordnance expert at the meeting, Lieutenant Colonel Keith Adamson, an officer at the army’s Aberdeen Proving Ground in northern Maryland, sneered at the idea of an atomic bomb—it was sheer fantasy. The colonel told Szilard and Teller in no uncertain terms that he did not believe “all this junk about complicated inventions.” “At Aberdeen,” he went on, ridiculing the physicists, “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.” 23 Adamson then proceeded to lecture Szilard and Teller about scientific boondoggles in wartime. “He told us that it was naive to believe that we could make a significant contribution to defense by creating a new weapon,” recalled Szilard. “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 in the end it is not weapons which win the wars, but the morale of the troops.” 24
Teller listened to Adamson with mounting frustration and anger. He had studied in Germany for many years and understood their military technology better than most—certainly better than the colonel. Finally he exploded. “If it is morale and not weapons that wins wars,” Teller said, his voice rising as his accent thickened, “then why does the Army need such a large arms budget? Perhaps its funding can be cut.” “All right, all right,” Adamson replied, “you’ll get your money.” 25 The Uranium Committee authorized all of $6,000 to purchase graphite, though Szilard and Fermi would not actually receive the money for several months. Briggs sent a report of the meeting to President Roosevelt on November first. He heard from the White House on November seventeenth. The president had read the report and wanted to keep it on file. “On file” is where it languished well into 1940.
Szilard and Teller left their meeting with the Uranium Committee frustrated and dejected. They felt trapped in a dilemma: to determine whether a nuclear chain reaction could be the basis for the development of an atomic bomb required a thorough scientific investigation; such an investigation required significant financial support, but the Uranium Committee would not give such support without compelling evidence suggesting probable success. Since they could not guarantee that a bomb would be available for wartime use, they could not attract the money for vital chain-reaction experiments. They felt as if they were “swimming in syrup.” 26
Months passed and nothing happened. Szilard’s frustration turned to anger. He decided to write a scientific paper about a chain-reacting uranium-graphite pile and threaten to publish it unless the government promised to move on fission research. The ploy worked. Within weeks of making his threat known, Columbia University received a grant of $6,000 for the purchase of graphite. 27 This allowed Szilard and Fermi to begin their experiments. They started by addressing two problems: the absorption rate of graphite and its effectiveness in slowing down neutrons. They set up the graphite in a square column several feet thick. Then they arranged lumps of uranium in a lattice configuration throughout the column, placed a neutron source inside the column, and measured the neutron activity with Geiger counters. The results led Szilard and Fermi to conclude that a very large pile would be needed to create and sustain a chain reaction. What is more, impurities commonly found in uranium and graphite would have to be eliminated because these impurities hungrily absorbed neutrons. All of this meant that a chain-reacting uranium-graphite pile would be very expensive in both materials and labor.
Meanwhile, Szilard traveled again to Princeton to see Einstein. They prepared a second letter for President Roosevelt that emphasized the secret German uranium research underway at the Kaiser Wilhelm Institute, which they had learned about from a Jewish chemist, Peter Debye, who had recently
been expelled from the institute. This second Einstein letter also stressed that Berlin had assumed direct responsibility for fission research and was stepping up its efforts to achieve a breakthrough. 28 In March 1940 Sachs sent the letter to FDR, who ordered the White House to consult the Uranium Committee. Briggs and Adamson cautiously said that nothing more should be done, pending the outcome of Fermi’s and Szilard’s work on neutron absorption in graphite. Bureaucratic caution prevailed once again.
Meanwhile, security officials busily developed a mind-set of distrust toward Szilard, Teller, Fermi, and other refugee physicists “of queer types and backgrounds.” 29 Agents categorized them as “aliens,” or in the case of Fermi, who came from Italy—an Axis country—as an “enemy alien.” A confidential report prepared by Army Intelligence in the summer of 1940 offered the following assessment of Fermi and Szilard:
(1) ENRICO FERMI. Department of Physics, Columbia University, New York City, is one of the most prominent scientists in the world in the field of physics. He is especially noted for breaking down the atom. He has been in the United States for about eighteen months. He is an Italian by birth and came here from Rome. He is supposed to have left Italy because of the fact that his wife is Jewish. He has been a Nobel Prize winner. His associates like him personally and greatly admire his intellectual ability. He is undoubtedly a Fascist. It is suggested that, before employing him on matters of a secret nature, a much more careful investigation be made. Employment of this person on secret work is not recommended.
(2) MR. SZELARD. It is believed that this man’s name is SZILLARD. He is not on the staff of Columbia University, nor is he connected with the Department of Physics in any official capacity. He is a Jewish refugee from Hungary. It is understood that his family were wealthy merchants in Hungary and were able to come to the United States with most of their money. He is an inventor, and is stated to be very pro-German, and to have remarked on many occasions that he thinks the Germans will win the war. It is suggested that, before employing him on matters of a secret nature, a much more careful investigation be made. Employment of this person on secret work is not recommended. 30