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… The intellectual experience was unforgettable.”
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. 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.” “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.
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.” The 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
To denotate [
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 afterthought 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 ofU235 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. This should devastate an area of more than 100 square miles.
The 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… The ultimate potential possibilities are now considered to be very much greater than at the time of the [last] report.”
The hydrogen bomb was thus under development in the United States onward from July 1942.
The 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.” The firm sent one of its best engineers to brief Met Lab leaders on production plans. “The scientists sat deadly still with curled lips. The briefer was ignorant; he enraged and frightened everyone.”
An exasperated Compton protegd, Volney Wilson, an idealistic young physicist responsible for pile instrumentation, called a confrontation meeting soon afterward 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 try-outs 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. Instead, it seemed to me that the primary issue was to get rid of Stone & Webster.
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. Then 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. “After 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. The 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, after four years of frustration, had begun to harden into stoicism. Late in September he drafted a long memorandum to his colleagues that addressed specific Met Lab problems but also considered the deeper issue of the responsibiUty of scientists for their work. In draft and more moderately in finished form his examination by turns compliments and savages Comp-ton's leadership: “In talking to Compton I frequently have the feeling that I am overplaying a delicate instrument.” Beyond personality Szilard pointed to a destructive abdication by those whom Compton led: “I have often thought.. that things would have been different if Compton's authority had actually originated with our group, rather than with the OSRD.” He elaborates in the finished memorandum:
The 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.
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. “There is a sprinkling of democratic spots here and there, but they do not form a coherent network which could be functional.” 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
