Big Science

by Michael Hiltzik

  By then, American science had been mobilized. In early December, Bush had brought together a small group to act as the bomb project’s civilian overseers: Conant, Briggs, Compton, Urey, and Lawrence. Compton was given the chairmanship of a new committee, known as S-1. (Bush considered, and then discarded, the idea of giving the chair to Lawrence, whom he ultimately considered too voluble. “The matter would . . . have to be handled under the strictest sort of secrecy,” he confided to Frank Jewett. “That is the reason that I hesitate at the name of Ernest Lawrence.”) S-1’s task, as Compton described it later, was to determine within six months “whether atomic bombs could be made.” If the answer was yes, the nation would provide virtually unlimited resources to make it happen.

  At the committee’s first meeting, they divided up the most important responsibilities. Lawrence would proceed with the magnetic separation technique he was already testing in the converted thirty-seven-inch cyclotron; Urey would develop a separation process based on gaseous diffusion, which exploited the different weights of vaporized uranium isotopes; Compton was to assemble a team to begin work on the actual bomb design. They agreed to meet again two weeks later.

  It was Saturday, December 6, 1941.

  Compton returned to his Washington hotel and penciled out a budget of $300,000 to cover the next six months. Lawrence drove to the airport for a flight home to Berkeley. Before taking off, he was informed that the first microscopic quantity of U-235 had been separated from natural uranium in the thirty-seven-inch cyclotron.

  The next day, as Compton was heading north by train from Washington to New York, where he was to meet with Fermi, a passenger boarding in Wilmington, Delaware, relayed the first sketchy radio reports of an attack on Pearl Harbor. Conant was already home in Cambridge, preparing with his wife to greet students arriving for a weekly four o’clock tea. Lawrence had disembarked from his flight and was home in Berkeley.

  Glenn Seaborg, the discoverer of element 94, was relaxing in his room at the Faculty Club, listening to a football game on the radio. Suddenly the announcer broke in with a news bulletin. Seaborg and his team had been working on a project so secret that they had been forbidden to publish anything about their work, and he instantly understood the impact that the electrifying news from Hawaii would have on his life and those of his colleagues: “Before, we’d been jogging toward our goal. Now we would be at a dead run.”

  Chapter Twelve

  * * *

  The Racetrack

  On December 18, less than two weeks after Pearl Harbor, the members of the S-1 Committee met again in Washington. They assembled in a very different spirit from that in which they had adjourned on December 6, their futures now clouded by the project to which they had all committed themselves on that final day of peace.

  Conant presided, with Lawrence, Briggs, Compton, Urey, and Eger Murphree, the research director of Standard Oil of New Jersey, in attendance. Their task was to choose the most effective method for producing the fissionable fuel for an atomic bomb from among five options, none of which was appreciably better than the others. The most speculative option involved element 94, that purportedly hyperfissionable substance discovered in Lawrence’s laboratory. Large-scale production of 94 would require a uranium chain reaction, which Fermi had not yet achieved. There were also four possible approaches for separating fissionable U-235 from natural ore. All relied on the weight disparity between isotopes 235 and 238, but all were experimental, and their potential for industrial-scale production conjectural. They were (1) gaseous diffusion, which involved passing uranium hexafluoride, a highly corrosive gas known unaffectionately to chemists as “hex,” through a porous barrier; (2) thermal diffusion, which exploited temperature differentials to coax the isotopes into separating; (3) electromagnetic separation, which was based on the divergent paths followed by ions of different weights when beamed through a magnetic field; and (4) the use of a high-speed centrifuge.

  Lawrence stunned his colleagues with the disclosure that the Rad Lab had isolated a microscopic quantity of U-235 on the very day before the attack on Pearl Harbor. Driven by frustration over the slow pace of the Uranium Committee’s work, he had taken it upon himself to pull his best staff members off the 60-inch and 184-inch cyclotrons and assign them to a crash conversion of the 37-inch into a mass spectrograph, an electromagnetic device used to separate ions. The conversion, which was quietly financed from Rad Lab funds and a supplemental $5,000 grant from the Research Corporation, entailed replacing the machine’s vacuum tank with a hastily designed new chamber fitted with an ion source of solid uranium chloride; new electrodes to ionize the vapor and accelerate the charged particles through the depressurized tank; and collectors on which the ionized isotopes would be deposited, hopefully in discrete clumps, after having traced divergent paths because of their different weights. The conversion had been completed on November 24, and the first ion beams hit the collectors exactly one week later, the two beams traveling semicircular trajectories about two feet in diameter and completing their journeys a fraction of an inch apart. By December 6, the spectrographers had accumulated their first measurable, if invisible, quantity of uranium 235—far from pure but at more than triple the concentration found in nature.

  Lawrence emerged from the meeting with the first contract issued by the S-1 Committee: a grant of $400,000 to pursue his electromagnetic separation method as well as “certain experimentation on certain elements of particular interest involving cyclotron work.” The oblique verbiage referred to element 94. When S-1 reconvened the next day, Compton was awarded responsibility for supervising the theoretical research on U-235 and plutonium. That gave him not only oversight of Fermi’s reactor research at Columbia, for which the committee made a six-month appropriation of $340,000, but also jurisdiction over the spectrograph and plutonium projects at Lawrence’s Rad Lab.

  This was an inherently unstable arrangement, given the self-regard of the two scientists. Sure enough, conflict between them broke open at the end of January, when Lawrence appeared in Chicago with a proposal to centralize all the plutonium and isotope work, including the atomic pile, at Berkeley. This was not purely a power grab. Compton and Lawrence shared an uneasiness about leaving Fermi’s reactor project at Columbia. Not only did they fear that New York City could be vulnerable to an attack launched from Europe, but also the university’s resources were already stretched thin by Urey’s gaseous diffusion research. Compton’s preference, however, was to transfer the atomic pile to the University of Chicago, the administration of which was eager to host it and where, as a professor of physics, he could oversee the project from his office on campus. Lawrence countered that Chicago’s experience with large-scale nuclear research was meager compared with that of the Rad Lab, which had support facilities to spare. And, of course, he felt he had more than enough administrative experience in large projects to oversee electromagnetic separation, plutonium, and the chain-reaction pile without overstretching himself.

  Compton was seized with a vision of Lawrence supplanting his own authority by the sheer exercise of will, abetted by geography. Compton had been entrusted with the overall responsibility of managing the production of atomic fuel for the bomb, which could not be delegated—already he had drafted a project schedule, starting with a deadline to determine whether a chain reaction was feasible (July 1, 1942) and ending with the assembly of a working bomb (January 1945). He was determined to push back firmly at Lawrence, but at that moment, he was placed at a disadvantage by a miserable case of the flu. The decisive confrontation took place by his sickbed upstairs in his home. There it was witnessed by a nonplussed Luis Alvarez, whom Compton had brought to Chicago to help him organize the bomb project. Alvarez was torn by his loyalties to both men; he had received his doctorate at Chicago under Compton and then had become a trusted staff member at Lawrence’s Radiation Laboratory. Now he was stuck in the middle of an increasingly acrimonious debate between the browbeating Lawrence and the bedridden Compton. The more Lawrence
pushed, the harder Compton pushed back. “In all the years I had been Arthur’s student,” Alvarez would recall, “I had never seen him fight so hard for anything.” Finally, Compton settled the argument by fiat: the pile would move to Chicago.

  “You’ll never get the chain reaction going here,” Lawrence shot back. “The whole tempo of the University of Chicago is too slow.”

  “We’ll have it going here by the end of the year,” Compton replied.

  “I’ll bet you a thousand dollars you won’t.”

  “I’ll take you up on that,” Compton said. At that moment, he and Lawrence realized that Alvarez, their student and protégé, was seeing them at their worst. Suddenly abashed, Lawrence said, “I’ll cut the stakes to a five-cent cigar.”

  “Agreed.”

  Compton would win the bet, though he never received the cigar.

  Lawrence was right about the Rad Lab’s capabilities, however. The lab had been operating virtually on a war footing for two years. Up to September 1939, Ernest had expected the cyclotron to sit out any war, advising J. Stuart Foster, who was hoping to make a military case for building a machine at the University of Toronto, that it was “difficult . . . to suggest concrete practical applications of the cyclotron in warfare.” But after the Nazi invasion of Poland and the family scare over John’s passage on the Athenia, he set aside his doubts and conjured up ways to put the machine’s capabilities to use in the war effort. Ever attuned to the ebb and flow of research funding, he recognized that the government stood to become as generous a financial backer as the medical foundations he had mined to build the sixty-inch. He became an assiduous collector of government contracts large and small, starting with the production of radioisotopes at a standard fee of $25 per hour of cyclotron time. By the summer of 1940, the flow of government money into the Rad Lab had grown into a torrent.

  The most marked manifestation of the trend was an enhanced standard of living for Rad Lab scientists placed on the government payroll as consultants. Martin Kamen, who was supervising isotope production on the sixty-inch, was compensated for his high-pressure responsibilities with a government stipend of $5,000 a year, a “mind-boggling” sum for a scientist who previously had eked out a penurious existence grant to grant. He promptly took advantage of the windfall by purchasing a beautiful eighteenth-century Tassini viola, lest the money be snatched away as abruptly and mysteriously as it had arrived.

  The lab’s traditionally frugal approach toward overhead also disappeared. One day Kamen was summoned to the office of financial fussbudget Don Cooksey, who instructed him to prepare a detailed requisition for equipment to perform chemical assays—and not to worry about the cost. Kamen took him at his word. Paging through a stack of chemical supply catalogs, he chose lavishly, not excepting a “Podbielniak fractional distillation apparatus with gold-plated seals and ground joints,” which he ordered mainly because he was curious to know what it looked like. Its price: $1,000.

  Kamen submitted the list and stood by uneasily as Cooksey, who had been known to hold lengthy conferences over requisitions worth a single dollar, scrutinized every entry. “Martin, I don’t think you understand the situation,” he said finally. “Don’t you think we should triple this order?”

  As the pace of war planning intensified, it soon became impossible to tell where the Rad Lab ended and the bomb program began. Among the scientists who made the transition with ease was Glenn Seaborg, whose research would prove to be among the most important in the war.

  Seaborg never lost his respect for the substance that would make his career. “Plutonium is so unusual as to approach the unbelievable,” he would write a quarter century later. “Under some conditions it can be nearly as hard and brittle as glass; under others, as soft and plastic as lead. It will burn and crumble quickly to powder when heated in air, or slowly disintegrate when kept at room temperature . . . It is unique among all of the chemical elements. And it is fiendishly toxic, even in small amounts.”

  Seaborg’s early life told the same quintessentially American story of immigration and assimilation as Ernest Lawrence’s, although his upbringing was rather more insular and culturally constrained than that in the Lawrences’ educated household. He was born in 1912 to Theodore Seaborg, a first-generation Swedish American, and his Swedish-born wife, Selma, in Ishpeming, a community in Michigan’s upper peninsula where the dirt streets were tinted red by the iron ore mined from tunnels underlying the town in a subterranean latticework.

  When Seaborg was ten, his parents fled the meager opportunities of Ishpeming, relocating to a small community just south of Los Angeles. There Glenn was raised in permanently straitened means, for his father never again found steady work. But Glenn was able to take advantage of the superb state university system of California, where tuition was free to residents. By 1933, he had received his bachelor’s degree in chemistry from the University of California at Los Angeles, which only a few years earlier had relocated from downtown Los Angeles to a bucolic new campus west of the city, and moved on to Berkeley to pursue his graduate studies in chemistry under Gilbert Lewis. He soon gravitated to the twenty-seven-inch cyclotron, which occupied the ramshackle old Rad Lab next door to Lewis’s domain, Gilman Hall.

  Chemistry skills like Seaborg’s were coming into demand at the Rad Lab. To the physicists, the separation and purification of radioisotopes seemed a black art; but it was well within the capabilities of a graduate chemist. In no time, Seaborg became one of the Rad Lab’s reigning radiochemistry experts while also serving as Lewis’s personal research assistant. Fortune had placed him in a position to plant one leg in each of the university’s two most renowned departments, standing at the very spot where they came together to promote the most exciting research on earth.

  The contrast between the two towering figures of Berkeley science was striking. Gilbert Lewis remained rooted in small science, happily puffing away on his acrid black cigars at a workbench festooned with hand-blown glassware. Lawrence, perfecting his style of Big Science, already was involved less in performing experiments than in managing his interdisciplinary staff. The Rad Lab was starting to operate on an industrial scale, with graduate students working in shifts to keep the cyclotron running round the clock. Ernest’s genius, Seaborg perceived, was to draw into his orbit like-minded scientists in every field, not just physics, and imbue them with his own drive to build and perfect his magnificent invention. Without Lawrence, there would be no Rad Lab—none of the teamwork that combined the disparate knowledge and skills of physicists, chemists, biologists, physicians, and engineers into a new paradigm of science.

  • • •

  Like his colleagues, Seaborg never forgot where he was the moment he first heard about fission: in his case, at Lawrence’s Monday Journal Club. He wandered the streets of Berkeley all that night, marveling at the discovery, cursing himself for not having recognized the phenomenon himself despite his hours of hands-on experience pulling isotopes from bombarded uranium, imagining the renown that would have come his way had the discovery been his, and hankering to join the full-scale assault on fission that Lawrence had ordered.

  His opportunity came through Ed McMillan. As one of the lab’s senior scientists, McMillan was at the hub of Ernest’s campaign to augment the discovery of fission by bombarding uranium and logging the reactions. The result that especially piqued his interest was a 2.3-day “activity.” (The term referred to the half-life of the isotope in question.) This activity, curiously, remained nestled close to the uranium target, unlike other fission products, which typically were driven some distance away by the energy of nuclear fragmentation. That suggested that the activity resulted not from fission but from some other reaction—most likely the absorption of a neutron by the uranium nucleus. If that neutron decayed into a proton, then the 2.3-day activity must be element 93, which had never been seen. It would also be the first element heavier than uranium ever found—the first transuranic.

  The rules of physics dictated that an element
with a half-life of 2.3 days had to be highly unstable. In turn that posed the possibility that it would decay rapidly into the next element up the line, element 94, which was likely to be especially vulnerable to fission. McMillan’s initial observations suggested that 94 would be exceptionally long lived, which was both a drawback and, in terms of the war effort, a virtue. The longer an isotope’s half-life, the more muted its radioactivity, and, therefore, the more difficult it was to detect. But a long-lived fissionable isotope, especially one that could be chemically separated from its uranium grandparent, might be especially suitable for a bomb.

  From his bachelor’s apartment in the Faculty Club, McMillan burbled incessantly about his work. Seaborg, who lived down the hall, was enthralled. At virtually every encounter—“whether at the laboratory, at meals, in the hallway, or even going in and out of the shower”—their conversation “had something to do with element 93 and the search for element 94,” Seaborg recalled. McMillan was closing in on the elusive new transuranic by watching for alpha emissions in 93’s decay products. One day he told Seaborg triumphantly that he had found an alpha emitter and had already ruled out that it could be an isotope of element 91, 92, or 93. It looked like element 94.

  Shortly after that, McMillan disappeared.