The Basis of Everything

by Andrew Ramsey

  Upon gaining responsibility for the Manhattan Project in September 1942, Groves began his first meeting with a group of the operation’s American-based scientific elite that included Oppenheimer and Arthur Compton by growling ‘you’re working for me now and you’d better toe the line’.3 He saw the members of the physics fraternity as military conscripts, albeit out of uniform.

  Groves was also unrelenting in pursuit of the Manhattan Project’s grandiose ambitions. It would be the largest-ever commitment of personnel and resources to realising a single scientific quest. Over the course of three years, it would employ more than 200,000 people and absorb an estimated US$2 billion (approximately US$25 billion today). And none of those who attended that meeting at the Pentagon on 10 September 1943 left it with any doubt as to the result they were chasing.

  ‘It was emphasized again and again,’ Oliphant would remember vividly, ‘that the prime object was the production of a military weapon in the shortest possible time.’4

  Groves disliked and distrusted the British, both personally and professionally, a resentment born of his experiences in the First World War. He would later excoriate ‘the general air of superiority which seems to be inherent in the English. Only the English could be so annoying towards everyone not of their nationality.’5 Groves was also suspicious of the commercial motives behind ICI’s involvement in Tube Alloys in Britain, and took pride in restricting interactions between individuals on either side of the Atlantic. In particular, he was deeply distrustful of Wallace Akers, who remained in charge of a depleted Tube Alloys in England.

  Groves held clear ideas on how the British contingent might best be absorbed into the Manhattan Project, if they must be involved at all. He wanted Chadwick and Oliphant to head directly to Oppenheimer’s Los Alamos laboratory, perched atop steep cliffs overlooking the New Mexico desert. It was one of more than a dozen project sites spread across the United States, all designed to operate in strict isolation and with no interchange of information except at the highest level, as per Groves’ inviolable instruction.

  Over the next three years, the Manhattan Project would reach across the length and breadth of America, and beyond. Research into uranium separation and fission experiments was conducted at numerous universities, including Lawrence’s Berkeley, Columbia in New York, and the University of Chicago, where the first controlled nuclear fission reaction was successfully achieved in December 1942. That historic moment, when the world’s first nuclear reactor – constructed on a squash court beneath the grandstands of Chicago University’s Stagg Field – underwent a self-sustaining chain reaction, used more than five tons of naturally occurring uranium metal and was overseen by Italian-born physicist Enrico Fermi.

  A huge uranium enrichment facility was established at a greenfield site in Tennessee, which later became known as the township of Oak Ridge. In addition to the heavy water production site located alongside the Chalk River in Ontario, Canada, the world’s first large-scale nuclear reactor would be built south of the Canadian border, at Hanford in Washington State. And the heart of bomb design and production would be the highly secret site at Los Alamos.

  Groves had hand-picked Oppenheimer to lead the weapons development operation – a controversial choice to many, given Oppenheimer’s known connections with Communist activities and sympathisers. Groves himself had initially been unconvinced of Oppenheimer’s suitability, because he boasted neither administrative experience nor a Nobel Prize.

  It was Oppenheimer who had selected the laboratory’s top-secret location. As a teenager, he had contracted a near-fatal bout of dysentery and spent a summer convalescing at a dude ranch in the Sangre de Cristo Mountains near the New Mexico capital Santa Fe. He saw this as an ideal site where such an audaciously secretive community might hide. The clandestine outpost would become home to thousands of workers, yet was designated by a single registered post-office box, and was known within the Manhattan Project’s inner sanctum simply as ‘Site Y’.

  After his unpleasant experiences at the Cavendish Laboratory, Oppenheimer had established himself as a formidable theoretical physicist. Before arriving at Berkeley, he had studied alongside Max Born and Niels Bohr at Germany’s Göttingen University in the mid-1920s, at the time they were developing the theory of quantum mechanics. A tall, aloof presence, Oppenheimer had a passion for philosophy and Eastern religion, for English and French literature, for fine arts and dry martinis that rendered him the antithesis of everything Groves represented. Yet the physicist’s brooding charisma made him hugely successful in securing recruits to work for him, even though many of them had no clue as to the project’s ultimate goal.

  From the outset, however, Oliphant did not see Los Alamos as the detail that best suited him. His interest was in the science of isotope extraction, not the complex ordnance calculations on how the bomb might be constructed, which occupied the great theoretical minds gathered in the New Mexico desert. Oliphant also saw far more appeal in working alongside his great friend Ernest Lawrence at the Berkeley lab that had hosted research into electromagnetic separation techniques for the past two years.

  Groves voiced surprise at Oliphant’s reluctance to follow Oppenheimer – who also wanted to work with the Australian – back to the isolated compound atop the red-earth mesa of New Mexico’s Pajarito Plateau. It would not be the last time that Oliphant would challenge Groves’ iron will.

  On this occasion, though, he was supported in his commitment to Berkeley by Chadwick, and in the end Groves recognised pragmatism ahead of his prejudices. So in early November 1943, Oliphant hauled himself into the depths of another B-24 bomber to take up his tenure as assistant – effectively deputy – to Ernest Lawrence on the shores of San Francisco Bay.

  * * *

  The first item that caught Oliphant’s attention on arrival at Lawrence’s California laboratory was the huge 184-inch cyclotron that had been taking shape on his previous visit, but was now completed and housed within a striking twenty-four-sided structure. The next was the sheer scale of the operation in which he had become embedded.

  In the wake of Oliphant’s 1941 crusade, Lawrence’s faith in the capacity of his cyclotron to successfully separate the required uranium-235 isotope had grown at the same rapid rate as the scope of his machines. While the practicality of the electromagnetic separation method was doubted by some physicists, Lawrence threw himself into the task of finding ways to improve its yields. As the cyclotron evolved, so too did its name change to the ‘calutron’, which recognised its conception in the radiation laboratory at Lawrence’s California University.

  Among the changes Lawrence had introduced was the use of ‘hot’ (high-positive-voltage) electrical energy, as opposed to a ‘cold’ (grounded) power source. Hot energy reduced the risk that insulators would fail, and therefore allowed the machine to make more efficient use of electricity. It also meant the calutron could employ multiple streams of charged particles rather than a single beam, which bolstered the potential for production of the fissionable isotope. As these charged uranium particles were fired through a strong magnetic field, the lighter and sought-after uranium-235 isotopes would be deflected more distinctly than the heavier uranium-238, which meant they could be collected in greater volumes (although still atom by atom) in the machine’s dedicated receivers.

  Once tested and further streamlined, this powerful machine would be replicated many times over on the bare expanse of Oak Ridge – later known as ‘Site X’ – where, from late 1943, the ‘racetracks’ around which the precious particles surged began slowly churning out the material needed to form the core of a bomb. The coils of the magnets these machines used were wound with silver sourced from the Fort Knox bullion depository, a total of about 14,000 tons that cost around US$500 million.

  While the weapons work was under way at Los Alamos, Oak Ridge was where the infrastructure for the different isotope separation methods being explored would be housed. Among Oliphant’s first assignments after arriving at Berkeley was to vis
it this facility, where he was stunned by the amount of building that had already taken place. Not even the all-pervasive layer of sticky, ochre mud that coagulated under late autumn rain on the Tennessee Valley floor could slow the pace of construction, which yielded up to 1000 new homes per month. Oak Ridge would eventually grow to house more than 50,000 workers, with the true nature of their task unknown to anyone outside the Manhattan Project and the compound’s regularly patrolled barbed-wire fences.

  The Oak Ridge facility ultimately hosted the three methods of isotope extraction that Groves and his scientists believed would most reliably produce sufficient uranium-235 for an atomic bomb. Under Groves’ relentless leadership, the three refinement methods – gaseous diffusion, electromagnetic separation and, eventually, thermal diffusion, which Otto Frisch had originally pursued at Birmingham – were effectively pitted against one another in a contest to prove which was the most productive.

  Although the thermal diffusion technique had been largely dismissed as being capable of yielding significant quantities of uranium-235, it was incorporated into the Oak Ridge set-up (in a plant codenamed S-50) in late 1944. By that stage, with the race to build the bomb becoming more and more urgent, all three separation methods were contributing to the precious uranium-235 resource.

  Initially, it had been expected that a majority of the enriched material would be collected through the gaseous diffusion process that had been recommended in the MAUD Report. However, the fears Oliphant expressed upon returning to Britain in early 1943 that the gaseous process was too cumbersome were soon revealed to be prudent. The intricate network of pumps and porous barriers that were needed to treat the toxic uranium hexafluoride gas in order to remove the rare uranium-235 isotope was installed in a huge plant at Oak Ridge codenamed K-25. It represented an extraordinarily ambitious engineering feat, which was regularly beset by breakdowns and maintenance problems.

  Oliphant’s mistrust of the gaseous diffusion method only grew after he had spent some time at Oak Ridge. It was scarcely surprising that he identified shortcomings, given the nature of the operation, which took laboratory experiments still effectively in their infancy and applied them on a mega-industrial scale in a race against time. The gaseous diffusion process relied upon a series of 4000 stages, each one dependent on the success of the other, thereby making it highly susceptible to shutdown should one of those steps malfunction. It also required the uranium hexafluoride gas to be pumped through an endless network of atomic sieves set with holes four-ten millionths of an inch (ten nanometres) in diameter.

  As a consequence, Oliphant’s support swung further behind electromagnetic separation, which employed a series of Lawrence’s calutrons arranged side by side in the huge elliptical ‘racetracks’. At the height of isotope production in late 1944, the electromagnetic facility, known as ‘Y-12’, housed nine racetracks comprised of more than 850 calutrons.

  In contrast to the temperamental and inter-related technology of the gaseous diffusion plant, the electromagnetic technique consisted of a huge number of standalone units that could operate in parallel rather than relying on the performance of each individual component. Not that it quarantined the fledgling technical operation from serious setbacks, as Oliphant quickly discovered. When he paid his first visit to Oak Ridge in late 1943, the calutron racetracks had ground to a complete standstill after rust and other impurities were found in the oil that circulated to keep the huge magnets cool. The repair job took months, and required the magnets to be taken apart, meticulously cleaned and then rewound.

  One reason why Lawrence pressed strongly within the Manhattan Project for Oliphant to join him in the separation work was that his Australian friend’s insight and experience – gained from working alongside Rutherford and then designing his own (still-unfinished) cyclotron at Birmingham – provided a natural fit with the application of electromagnetism. And Oliphant duly hurled himself into his role as Lawrence’s right-hand man with customary vigour.

  Much of the expertise that Oliphant was to provide stemmed from the skill that had first won him notice as a scientist: his ability to troubleshoot equipment problems. Since it had started to take shape in mid-1943, the Y-12 electromagnetic plant had been plagued by faults that arose from its novelty and complexity. The calutrons, which stood vertically, initially suffered from vacuum tank leaks, often because they were knocked out of alignment by the massive magnetic pressure being generated. Welds regularly failed, electrical circuits shorted out, and it took time for the machines’ operators to learn the tricks and pitfalls of handling such temperamental apparatus.

  The work that Oliphant had previously envisaged undertaking at his cyclotron in Birmingham was being pursued in a different manner by Lawrence, through the use of his calutron, which (unlike the cyclotron from which it had evolved) relied on magnetic force and did not utilise large-scale electric fields. But as Oliphant familiarised himself with the equipment and its methods, his faith in this new technology began to mirror Lawrence’s.

  In November 1943, just months after joining the Manhattan Project, Oliphant wrote to General Groves and betrayed some of his own frustration that the ongoing teething problems delivered. ‘The electromagnetic method as developed [at Berkeley], and as under construction at Site X [Oak Ridge], is without doubt capable of the performance claimed for it,’ he wrote. ‘Beyond the accidents and failures due to faulty mechanical and electrical design, which are difficult to condone, the electromagnetic separation system is free from all uncertainties.’6

  In Oliphant’s assessment, once the electromagnetic method’s operational issues were smoothed out, a critical mass of uranium-235 – perhaps 20–30 kilograms – should be successfully harvested by the end of the following year, 1944. This would happen even sooner if Groves took up Oliphant’s pointed suggestion that the size of the electromagnetic plant be increased ‘at once by a factor of five’.

  ‘In fact, I would go further to say that unless this is done I cannot see that the nuclear weapon will be of military value in this war,’ Oliphant bluntly warned.7

  It was one of a number of recommendations from Oliphant that the general chose to ignore.

  * * *

  Oliphant’s role as Lawrence’s trusted deputy meant he spent his time oscillating between Oak Ridge, Washington and Berkeley (the environment he preferred), and even made one fleeting visit to Los Alamos. But he was also effectively second-in-charge to Chadwick among the British delegation. As a result, his counsel was often sought by his former Cavendish colleague, even though Chadwick was the only member of the team with authority to know what was happening across other sectors of the Manhattan Project.

  It was in the guise of notional second-in-command that Oliphant would make numerous trips between the United States and Britain over the remainder of the war. They involved a sixteen-hour journey that proved a trial for even the hardiest of flyers, of which Chadwick was not one, which meant much of the essential commuting was delegated to Oliphant.

  Conditions were far more rudimentary than the flight-deck privileges he had enjoyed aboard the B-24 from Scotland to start his lobbying mission two years earlier. As merely another body passing through the revolving door of academics, bureaucrats and military brass carried over the Atlantic, he was relegated to the bomb bay along with other rank-and-file travellers.

  Rather than a jockey seat in the cockpit, he was routinely allocated a thin mattress spread over the aircraft’s bomb doors. He was able to manoeuvre his lanky frame, clad in a bulky flying suit, to jam his boots against one side of the metal fuselage and push his head against the edge opposite, using his parachute pack as a pillow. The constant roar of four super-charged engines, coupled with the sub-zero drafts that rushed through gaps in the Flying Boxcar, made sleep impossible. Besides, passengers needed to maintain a vigilant eye on the altimeter hung overhead, lest oxygen masks be needed.

  In this way, he endured not only the primitive discomforts but also the unpredictability of fellow travellers, i
ncluding one who became so overwrought by the experience that he deployed his inflatable lifejacket while thrashing about in panic. The disoriented man then failed to fit his oxygen mask during a toilet visit and promptly passed out, leaving Oliphant and another passenger to dash to his rescue and drag the barely conscious man back to his mattress. At that point, the rip-cord of the patient’s parachute snagged and a huge silk sheet filled the already cramped confines, billowed by the icy winds that whistled though the darkness.

  * * *

  When it came to the manifest details of personnel being shuttled back and forth across the Atlantic, Oliphant appreciated the non-negotiability of secrecy provisions. Yet in other respects, the adherence to absolute confidentiality that Groves both preached and practised offended Oliphant’s belief in the unhindered exchange of scientific knowledge. And as the Manhattan Project grew in size and intricacy throughout 1944, this would increasingly land him in hot water, not unlike the heartburn his indiscretions generated during the radar program.

  At one point, he came to the attention of General Groves via the transcript of an unauthorised telephone call made from an office at Berkeley, in which Oliphant discussed matters relating to the deployment of other British staff within the Manhattan Project. While that breach was scarcely the stuff of national security, it meant Oliphant would be closely monitored.

  That became apparent to him soon afterwards, when he was returning from an evening stint with Lawrence at the giant calutron atop the hill overlooking the Berkeley campus. He approached his office to find a light blazing and a pair of plain-clothes FBI agents rifling through his filing cabinet, where he carefully locked away some of his more incendiary correspondence.