Inside the Centre: The Life of J. Robert Oppenheimer

by Ray Monk

  In later summer, after a review of the experimental work, 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. We therefore sought to establish this laboratory for a direct attack on all the problems inherent in the most rapid possible development and production of atomic bombs.

  He also says that, when Groves assumed control of the project, ‘I discussed with him the need for an atomic bomb laboratory’, and reveals that he, at least, was happy with the idea of ‘making it a Military Establishment in which key personnel would be commissioned as officers’, even to the extent of taking the first steps towards joining the army himself.

  If this is what Groves meant by ‘the results of his study and the methods by which he had reached his conclusions’, then one can see why he liked what he heard so much. From the other scientists he had been met with either condescension and hostility or a resolute determination to impress and appear upbeat. Now here was a scientist talking Groves’s language and echoing his own thoughts and frustrations, expressing the dissatisfaction that he himself had felt about the pace of the work being carried out, and emphasising the need for a major change in the organisation, for more central control, in order to get the project moving more quickly. All this, one imagines, was music to Groves’s ears.

  So impressed was Groves that a week later, while he was again visiting Chicago, he asked Oppenheimer to join him in order to discuss his idea of a central laboratory. Then, when the time came for Groves to leave for New York, he asked Oppenheimer to accompany him on the journey. So it was that Oppenheimer and Groves, together with Kenneth Nichols and Colonel Marshall – all four of them squeezed into a tiny compartment on a train – discussed how and where the bomb laboratory might be created. From this conversation the idea of a single laboratory was developed, now envisaged as a place, preferably in a remote location away from prying eyes and ears, where all the scientists working on the design and production of the bomb – rather than on chain reactions, methods of isotope separation, and the like – could be gathered together. There, under the watchful control and guidance of the military, the scientists could pursue their work, while sharing with each other (but not with anybody else) their ideas and information.

  Before he set off for Chicago, Oppenheimer wrote to John Manley, the experimental physicist who had been appointed as his assistant, telling him that Groves had seemed ‘convinced of the necessity for proceeding immediately with the construction of the laboratory and the reorganization of our work’. He also advised him that ‘some far reaching geographical change in plans seems to be on the cards’, since Groves had apparently gone off his original idea of placing the laboratory at Oak Ridge (in fact, Oppenheimer had talked him out of it, on the grounds that the laboratory should not be envisaged as a mere appendage of the isotope-separation plant).

  Manley, who was a specialist in neutron physics, had worked with Fermi and Szilard at Columbia before taking up a position at the University of Illinois in 1937. Since January 1942 he had been a member of the Met Lab at Chicago, where he remained after his appointment as Oppenheimer’s assistant in fast-neutron research. ‘I let myself be persuaded to join Oppenheimer with some misgivings,’ he later recalled. ‘I had only briefly met him. I had given a colloquium in Berkeley a year or two before and I was somewhat frightened of his evident erudition and his lack of interest in mundane affairs.’

  To Manley’s surprise, he and Oppenheimer got on well. While Oppenheimer and his team at Berkeley made calculations, Manley’s task was to supply them with measurements taken from experiments using the particle accelerators at no fewer than nine universities. ‘I can’t tell you how difficult those experiments were,’ Manley wrote. ‘The amounts of material to work with were infinitesimal . . . just practically invisible quantities.’ Particularly frustrating was the problem of liaising with the various centres of research, which was the main factor in persuading Oppenheimer and Manley of the need for a single laboratory.

  In a subsequent letter written after his train ride to New York with Groves, Oppenheimer told Manley that Groves had been out west and that ‘the question of site is well along toward settlement’. Evidently, by this time (the first week of November 1942), Oppenheimer had managed to steer Groves’s thoughts about the location of the laboratory towards the countryside that Oppenheimer knew and loved best: the mountains of northern New Mexico. ‘It is a lovely spot,’ Oppenheimer told Manley, ‘and in every way satisfactory, and the only points which now have to be settled are whether the human and legal aspects of the necessary evacuations make insuperable difficulties.’ The delicate nature of one of these difficulties is perhaps indicated at the end of the letter, where he reveals that he is not sending a copy of it to Compton. He would, he wrote, be happy if Manley told Compton ‘anything about the developments in physics that you think he would like to hear’. But, he implored: ‘Don’t tell him about the laboratory.’ As he grew closer to Groves, as the theoretical subgroup of S-1 that he headed acquired a greater and greater role, and as the plans for a central laboratory seemed more and more likely to succeed, Oppenheimer surely guessed that Compton’s position as the head of the scientific aspect of the Manhattan Project was likely to be short-lived. If the plan for a central laboratory went ahead and Oppenheimer were placed in charge of that laboratory, then, instead of Oppenheimer working as a consultant for a project headed by Compton, Compton would, in effect, be working for a project led by Oppenheimer.

  On 16 November, Oppenheimer, together with Ed McMillan and Colonel Dudley, visited Jemez Springs, New Mexico. In the afternoon they were joined by Groves, who, confirming the view that Oppenheimer and McMillan had already come to, pronounced abruptly as soon as he arrived: ‘This will never do.’ The canyon was too deep, its walls too steep to consider as a suitable spot for a major programme of building. Oppenheimer then suggested as an alternative a boys’ school on the east side of the Jemez range that was built on a flat mesa: the Los Alamos Ranch School. ‘As soon as Groves saw it,’ McMillan later recalled, ‘he said, in effect, “This is the place.”’ On 7 December 1942, the school was issued with a formal notice of eviction, and it closed the following February. A month after that, the first scientists arrived at what was, by then, a bomb laboratory. Officially, it was now called ‘Project Y’.fn45

  From the time that Oppenheimer and Groves first discussed the possibility of a single laboratory in October 1942 until the time that scientists began arriving at Los Alamos in March 1943, there seems to have been an assumption, particularly on Oppenheimer’s part, that he himself would be appointed as its director. However, it is far from clear when the decision was made to appoint Oppenheimer as the head of this laboratory.fn46 He did not receive his formal letter of invitation to take up the post, signed by Conant and Groves, until February 1943, but the decision must have been taken at least a month or two before that. In Now It Can Be Told, Groves discusses the decision at some length, emphasising that, although Oppenheimer had headed the Berkeley study group, ‘neither Bush, Conant nor I felt that we were in any way committed to his appointment as director of Project Y’. Moreover, ‘no one with whom I talked showed any great enthusiasm about Oppenheimer as a possible director of the project’.

  There were, as Groves makes clear, some very powerful reasons for that lack of enthusiasm. Not only had Oppenheimer never directed a laboratory of any kind before, but he had never directed anything. He ‘had had almost no administrative experience of any kind’, as Groves puts it. Also (and this point seems to have weighed particularly heavily on Groves’s mind), Oppenheimer, un
like the heads of the major laboratories associated with the Manhattan Project – Compton at Chicago, Urey at Columbia and Lawrence at Berkeley – did not have a Nobel Prize. He thus, says Groves, lacked ‘the prestige among his fellow scientists that I would have liked the project leader to possess’. Finally there was the problem that, as Groves puts it, Oppenheimer’s ‘background included much that was not to our liking by any means’. This last problem was to rumble on for some months after Oppenheimer’s appointment, with the security organisation (‘which was not yet under my complete control,’ Groves writes) unwilling to grant clearance to someone with so many links to important communists.

  In his book, Groves seems to suggest that he appointed Oppenheimer, despite the many reasons not to, simply because ‘it became apparent that we were not going to find a better man’. Of the ‘better men’ he considered, Lawrence could not be spared from the electromagnetic project, Compton could not be spared from Chicago, and Urey, as a chemist rather than a physicist, was not qualified. There were, of course, other possibilities – Lawrence pushed hard for Groves to appoint Ed McMillan – but it is fairly clear that Groves liked Oppenheimer and believed strongly that he was the man for the job. When Oppenheimer was asked many years later to explain why Groves chose him, his reply illustrated why throughout his life he had struck people as arrogant. Groves, he said, ‘had a fatal weakness for good men’.

  By 30 November 1942, when he wrote to Conant summarising the results of recent scientific work, Oppenheimer seemed already to regard himself as the de facto head of the new laboratory. He speaks of ‘the men we are after’, and warns Conant:

  The job we have to do will not be possible without personnel substantially greater than that which we now have available, and I shall only be misleading you and all others concerned with the S-1 project if I were to promise to get the work done without this help.

  As it turned out, the men Oppenheimer was after included many of the top scientists in the country. To get them, as he was advised by both Isidor Rabi and the Cornell physicist Robert Bacher, he would have to drop the idea of the laboratory being a military establishment. The scientists he wanted and needed, they told him, would hardly be willing to join the army and conduct their research in uniform.

  Having shelved that idea, Oppenheimer – clearly in as great a hurry as Groves to get the project moving – was able to recruit many of the people he wanted by the end of the year. In this he was helped enormously by Manley, who knew personally almost every physicist in the US working on fast-neutron research. As Manley remembers: ‘I was supposed to talk to people in the fast neutron groups at Princeton and Wisconsin and try to persuade them to come to Los Alamos.’ One problem with this was that Manley himself had never been to New Mexico and knew nothing about Los Alamos:

  So I dug out some maps of New Mexico and I looked all over those maps trying to find where it might be. He’d said it was near the ‘Hamos’ Mountains, and I looked for HAMOS and I couldn’t find it on the map, on any map of New Mexico. I hadn’t any Spanish and, of course, I didn’t know that those doggone mountains are spelled JEMEZ.

  Despite his inability to find Los Alamos on the map, Manley did succeed in persuading most of the physicists he spoke to to join the project.

  Equally important was his success in appropriating the machines that the experimentalists would need. From Wisconsin he obtained two Van de Graaff generators, from Harvard a cyclotron, and from Illinois his own Cockcroft–Walton accelerator. To make tracking these things more difficult, they were sent first to a medical officer in St Louis, Missouri, and from there to Los Alamos. The difficulty of getting the necessary equipment to the remote spot in the New Mexico mountains made Manley wonder ‘whether, if Oppenheimer had been an experimental physicist and known that experimental physics is really 90 per cent plumbing and you’ve got to have all that equipment and tools and so on, he would ever have agreed to start a laboratory in this isolated place’.

  Much as he respected and grew to admire and like Oppenheimer, Manley was, especially to begin with, acutely conscious of Oppenheimer’s lack of experience of both laboratories and administration, and took a good deal of persuading that Oppenheimer was actually capable of administering a large laboratory. His doubts were increased by the fact that Oppenheimer seemed to take so little interest in how the laboratory might be organised. ‘I bugged Oppie for I don’t know how many months about an organization chart – who was going to be responsible for this and who was going to be responsible for that. But each time he would seem to be as unresponsive as an experimental physicist would think a theorist would be.’ Finally, in January 1943, Manley flew out to California and went to Oppenheimer’s office. As he pushed open the door he noticed that Edward Condon was there: ‘Oppie practically threw a piece of paper at me as I came in the door and said, “Here’s your damned organization chart.”’

  The organisation described by the chart, which remained in place for the first year of the laboratory’s existence, divided the lab into four main sections: 1. Theoretical, which initially was to be led by Oppenheimer himself; 2. Experimental, headed by Robert Bacher; 3. Chemistry and Metallurgy, led by the Berkeley chemist Joseph Kennedy and the British-born metallurgist Cyril S. Smith; and 4. Ordnance, which would, in time (it took some months to find the right man for this job), be headed by William ‘Deak’ Parsons of the US navy. Each of these divisions (except the Theoretical Division, which was by far the smallest) was split into groups, so that, for example, the Experimental Division contained a ‘Cyclotron Group’, led by Robert Wilson, which was charged with (among other things) the crucial task of measuring the time it takes for neutrons to be emitted after fission. Manley himself was put in charge of the ‘D-D Group’, which had responsibility for determining by experiment which material (candidates included tungsten, carbon and beryllium) could best be used as a ‘tamper’ to bounce escaping neutrons back into the fissioning uranium, thereby improving the bomb’s efficiency.

  The reason Condon was in Oppenheimer’s office was that Oppenheimer had decided to appoint him as associate director of the laboratory. Oppenheimer’s first choice for that role was another old friend from his student days in Europe, Isidor Rabi, but Rabi could not be persuaded to accept the job. He had several reasons for not wanting to move to Los Alamos. First, his wife, Helen, was vehemently opposed to going there. Second, Rabi thought the project to build a fission bomb had only a fifty-fifty chance of success. And third, he considered the work he was then doing on radar to be a crucial contribution to the war effort. Fourth, and perhaps most importantly, he was, as he later wrote, ‘strongly opposed to bombing’, on the grounds that ‘You drop a bomb and it falls on the just and the unjust.’ Nevertheless, he was prepared to act as a consultant on the project, and came often to oversee developments and offer advice.

  The first piece of advice Rabi offered was to make an important change to the organisation chart that Oppenheimer had drawn up. There was simply no way, Rabi urged (and Bacher seconded), that Oppenheimer could combine being director with being head of a division. Oppenheimer thus changed his mind and put Hans Bethe in charge of the Theoretical Division, a choice that was as obvious as it was excellent, but which offended Edward Teller, who felt that he should have got the job.

  While Oppenheimer and Manley were arranging the Los Alamos laboratory, the Met Lab in Chicago achieved the first fundamentally important milestone in the pursuit of a fission bomb by creating the world’s first chain reaction. It happened on 2 December 1942, a very cold Chicago winter’s day. Fermi, knowing the time was right for the pile he had constructed to go critical, had gathered about twenty people in the rackets court at Stagg Field, and was conducting affairs with complete confidence that everything would go as planned. One of the people present was the physicist Herb Anderson, who remembers: ‘the sound of the neutron counter, clickety-clack, clickety-clack. Then the clicks came more and more rapidly, and after a while they began to merge into a roar . . . Suddenly Fermi r
aised his hand. “The pile has gone critical,” he announced.’ Compton, who had watched the momentous event, returned to his office and phoned Conant. ‘The Italian navigator has just landed in the New World,’ he told him.

  Within a few weeks of this dramatic demonstration that a controlled nuclear reaction was possible – and the consequent realisation that plutonium could indeed be manufactured on an industrial scale – work started on two sites that together would constitute an almost unimaginably huge engineering project. In addition to the site in Oak Ridge, Tennessee, the Manhattan Project acquired a site at Hanford in the state of Washington, which would be used for a series of plutonium-producing reactors, the prototype of which was quickly constructed at Oak Ridge. Immediately, the Army Engineering Corps began to supervise the building of houses, the construction of roads and the recruitment of workers. Each site would require tens of thousands of people. Within a few months, both Hanford and Oak Ridge would be fairly sizeable towns. In areas where the depression of the 1930s had led to large-scale unemployment, the prospect of well-paid work was extremely welcome and neither site had trouble finding the requisite workforce, even though the people thus hired were told nothing about the purpose of the work they were doing. It is one of the most extraordinary aspects of the Manhattan Project that the existence of an atomic-bomb building programme was successfully kept secret from the very people who worked on the plants that supplied the necessary fissionable material.

  At its peak, the Manhattan Project employed more than 150,000 workers, the majority of whom worked at Oak Ridge or Hanford. They included more than 80,000 construction workers and about 68,000 operations and research personnel. Most of the latter were employed on dull, repetitive tasks that were necessary to keep the isotope separation plants and the reactors going. An excellent social history of the Manhattan Project, Atomic Spaces by Peter Bacon Hales, has attempted to convey what it was like to work at these sites. ‘New workers entering these factories,’ Hales writes, ‘found them to be confusing and sometimes terrifying warrens of piping, walls of analog dials, valves and knobs, marked with Bakelite labels in the arcane language of the engineer. The electromagnetic plant alone used close to 250,000 valves to control the materials coursing through 1,175 miles of piping.’