3—
The Widening Gyre

As a member of the Laboratory cycled through his apprenticeship, the center of his motion was, of course, Lawrence, who ultimately assigned duties and stipends, approved research projects and the publication of research results,^[113] and found jobs for journeymen cyclotroneers. His first revolutions occurred, as we have seen, in synchrony and usually in harmony with other members of the Laboratory. As his knowledge increased, he might spiral further out, occasionally colliding productively with members of Oppenheimer's group, of the College of Chemistry, or of the Medical School. Further turns might bring interactions with people from Stanford or Caltech, until—to finish with the analogy—the complete cyclotroneer would shoot forth from the Berkeley machine to build elsewhere what he had been taught to build at home. We shall examine a few turns of the spiral.

Around Mecca

In the beginning, until 1935, the disciples, or some of them, worked directly with the prophet, or, better, "the high priest."^[114] But as the administrative burden and the complexity of the machine increased, Lawrence became more and more removed from the work and workers in the Laboratory. He could be very generous to his students—some parents praised him lavishly for his kindness to their offspring—but he could also be impatient and

unreasonably demanding when the machine stopped.^[115] His impatience was enhanced by his frequent colds, picked up on his travels.^[116] He was often away from the Laboratory lecturing, at meetings of the National Academy of Sciences or the American Physical Society, and fund-raising (which he did to greatest effect in person in New York, where all his main supporters among foundations had their headquarters). These trips occupied more time than they need have done, since Lawrence insisted on going by train; he had worked out that flying was dangerous, that the chance of a fatal accident in a round trip from San Francisco to New York was one in a thousand, and would have nothing to do with airplanes.^[117] No doubt the long journeys by rail were necessary to him for quiet relaxation and unhurried future planning. After the settlement of 1936, Lawrence was in Berkeley long enough to encourage the staff and create his family. Otherwise he left the execution of his plans to Cooksey.^[118]

Lawrence retained his boyishness and ebullience for successes of the Laboratory and for approaches to his backers. It was only natural that he would come to identify with the men of wealth on whom he had come to depend and who appeared to like his company. He enjoyed the entertainments of New York bankers and brokers; he liked the style of Alfred Loomis, whose patronizing of the Laboratory, which began late in 1939, included a weekend at the plush Del Monte Hotel in Carmel for the Sprouls, the A.H. Comptons, the Vannevar Bushes, and the E.O. Lawrences. In these tastes and associations, Lawrence was followed, as in much else, by Alvarez.^[119] In the same line, Lawrence set some store on

family background; whenever the ancestry of his students permitted it, he would include in his letters of recommendation the irrelevance that they came "of good family."^[120] He came to dislike nonconformity (to his ideas!) and liberal causes, to hold that "science is justified only to the extent that it brings substantial riches to mankind," and to declare research scientists—among whom he enrolled himself—to be "essentially conservative people."^[121] In these sentiments he disagreed altogether with his colleagues Urey, A.H. Compton, and, closer to home, Oppenheimer, whose personal style influenced the apprentice theorists at Berkeley at least as much as Lawrence's helped define the cyclotroneer.^[122]

The contrast between the two men is the stuff of stories.^[123] Lawrence grew up in rigid and rigorous South Dakota, worked during high school, learned to build radios, went into physics, knew little else, had no regrets, never doubted his way. Oppenheimer came from a wealthy Jewish family, grew up surrounded by books and pictures, attended the indulgent Ethical Cultural School, collected beautiful rocks, had literary ambitions, drifted into physics, suffered severe depressions. He also suffered from cultural ambitions, which caused him to learn, or affect to know, diverse languages, good food and wine, the best in music, painting, and books; he would take girls to dinner and read them Baudelaire; he sketched in charcoal and painted in oils; at Berkeley he studied with professors of Sanskrit, read Plato in Greek, and, what was worse, talked about it.^[124] They moved in opposite directions

politically under the strong polarizing forces of the late 1930s. Lawrence trusted that the world would muddle through without requiring his attention. He had faith in the great powers, which, he thought, had established at Munich that international disputes would be settled by peaceful negotiations; "I am not concerned about the political atmosphere," he reassured Cockcroft, concerning a meeting in Europe planned for September 1939, "which I personally think will be all right." Oppenheimer did not allow the world to get on without his help. While Lawrence drifted complacently to the right, he rushed to the left, to the support of the Spanish Loyalists, American labor, and other pinkish causes.^[125]

It might therefore appear astonishing that from Oppenheimer's first semester at Berkeley in 1929, he and Lawrence were fast friends.^[126] His Jewishness bothered him more than it did Lawrence; as one of his Harvard professors once wrote, by way of recommendation, "Oppenheimer is a Jew, but entirely without the usual qualifications of his race."^[127] The basis of their friendship was their fundamental honesty, kindness, and openness, qualities each would soon enough come to compromise. They also shared a liking for, and for showing off, feats of physical prowess. Oppenheimer delighted in long journeys by horseback through remote reaches of New Mexico and surprised those foolhardy enough to accompany him by his stamina. Lawrence visited the Oppenheimer family retreat near what became the Los Alamos Laboratory once or twice, but preferred to take his exercise on the tennis court or in a small boat bought with the proceeds of the Comstock prize. "He plays a good game of tennis," said the Scientific American , "[and] has a cruising boat on San Francisco Bay that he won't take out unless there is rough water."^[128]

At the professional level, Lawrence and Oppenheimer esteemed each other as physicists, recognized each other's ambitions, saw that they did not conflict, and possessed the tie natural to the men expected by their Department to raise Berkeley physics to national distinction. "For all his sketchiness, and the highly questionable character of what he reports," Oppenheimer wrote, "Lawrence is a marvelous physicist." "He has all along been a valued partner," Lawrence allowed in support of Oppenheimer's promotion to full professor. He might have added: "His physics [is] good, but his arithmetic awful."^[129] Where Lawrence misinterpreted and mismeasured, Oppenheimer erred by factors of 100 or 1,000. When he was close. Here is a compliment from a German theorist who followed his calculations for pair production: "Oppenheimer's formula . . . is remarkably correct for him, apparently only the numerical factor is wrong."^[130]

Oppenheimer himself did not trust the theories he elaborated. He wrote his brother in 1932: "The work is fine: not fine in the fruits but the doing. . . . We are busy studying nuclei and neutrons and disintegrations; trying to make some place between the inadequate theory and the revolutionary experiments." And again, in 1934: "As you undoubtedly know, theoretical physics . . . is in a hell of a way."^[131] For a time Lawrence thought that Gamow would be more helpful than Oppenheimer; but he could offer only theoretical dollars, and nothing came of his effort to bring Gamow to Berkeley.^[132] Thereafter Lawrence and his Laboratory had only the theoretical advice they obtained casually from Oppenheimer's group and from an occasional short-time visitor. It is likely that Lawrence shared the views of his old friend Ernest Pollard of Yale. "To tell the truth, I don't absolutely think any current

nuclear theory worth much, but theoreticians regrettably have the power to divert thought from a constructive interpretation of experiment which doesn't agree with the present pervading jargons."^[133]

The most productive interaction between Lawrence's and Oppenheimer's groups concerned the hypothesis of deuteron disintegration, which Oppenheimer at first accepted fully and with a certain pleasure: "that makes, as far as I can see, a hopeless obstacle to Heisenberg's pseudo q.m. [quantum mechanics] of the nucleus." But the implausibility of the consequent character of the deuteron gave him pause, and he accepted the explanation of contamination long before Lawrence did. From the shambles, as we know, he and his former doctoral student, Melba Phillips, extracted the Oppenheimer-Phillips mechanism, which did help importantly in the interpretation of disintegration experiments at the Laboratory.^[134] There are a few other cases of productive interaction beyond the mixed advice Oppenheimer gave at the weekly seminars: his postdoc Robert Serber's analysis of the proton-proton scattering experiments of Lawrence's student Milton White; McMillan's measurements of absorption of g rays, in rough confirmation of calculations by Oppenheimer and Furry; and Oppenheimer's explanation of Henderson's results on the energy dependence of the disintegration of lithium by protons.^[135]

These interactions belong to the early years, when Oppenheimer felt a responsibility to help to elucidate disintegration. After 1936 the most useful of Oppenheimer's group for Lawrence's work was Sydney Dancoff, who pushed the theory of isomeric and radioactive transitions beyond what the European theorists had achieved and did not disdain to calculate the absorption of neutrons in the

cyclotron's water shielding. This unusual interest on the part of an Oppenheimer theorist in problems central to the Laboratory inspired a still rarer thought on Lawrence's part, one perhaps not expressed since the unsuccessful approach to Gamow: the thought of adding a theorist to the Laboratory's staff. Oppenheimer did not think that a very promising employment, and Dancoff went to join Serber in Urbana.^[136]

A rough measure of the closeness of the two groups may be obtained from an analysis of the composition of the thesis committees on which Lawrence served during the 1930s. Between 1931 and 1941 inclusive, thirty-seven theses were completed under these committees, twenty-one of which had Lawrence as nominal director. His associates on the thirty-seven committees divide into two classes, those with six to eight appearances and those with three or fewer, except for Leonard Loeb, who figures four times. Those in the first class: experimentalists R.T. Birge (units), R.B. Brode (cosmic rays), F.A. Jenkins and H. White (spectroscopy), theorist Oppenheimer, and chemists G.N. Lewis and Willard Libby. Perhaps the strongest showing was Libby's, who tied with Oppenheimer with eight appearances, on half of which he was the principal reader. On this showing, Lawrence's students—that is, students in experimental nuclear physics who had Lawrence as their nominal thesis director—were no closer to Oppenheimer than they were to any other active member of the Physics Department or to chemists interested in nuclear processes.

The makeup of these committees does not indicate anything about casual consultation of Oppenheimer or his students by perplexed members of the Laboratory. For graduate students, we have some measure of the extent of this consultation: six of them who had Lawrence but not Oppenheimer on their committees thank both Lawrence and Oppenheimer for advice.^[137] Also,

Oppenheimer's students occasionally did a calculation or elucidated a theoretical point for Lawrence's: for example, Willis Lamb's explanation of Laslett's failure to detect decay in Na²² and Eldred Nelson's collaboration with Alvarez and Carl Helmholz on the behavior of isomeric silver nuclei.^[138]

Just as many (we do not say all!) of Lawrence's "boys" adopted his rough-and-ready approach to physics and had little time or interest in much outside the Laboratory, so Oppenheimer's aped his gestures, tried to acquire his tastes, went to concerts, and talked books, art, and politics.^[139] A Lawrence man rushed through his preparation, knowing that, if he did well, he would have a choice of eligible positions; an Oppenheimer man proceeded with greater leisure, knowing that the art was long, and "jobs for theorists . . . not too common."^[140] The divergent cultures of the theorists and experimenters, the problematic state of nuclear theory, the peculiar fascinations of the cyclotroneers, and the increasing importance of biomedicine in the Laboratory worked to prevent the development there of the sort of theory-driven experiments that mark the big-machine physics of the postwar era.

Perhaps more important for the direction of nuclear science at the Laboratory than its relations with Oppenheimer's group and even with the entire Physics Department was its interactions with the College of Chemistry. Besides Lewis and Libby, there was Seaborg, who became the Laboratory's most productive chemist in 1937. As an instructor in the College of Chemistry, which he became in 1939, after two years of easy service as Lewis's assistant, Seaborg brought excellent doctoral students to do nuclear chemistry around the cyclotron, with consequences that were literally earthshaking.^[141] Another young chemist closely associated with the Laboratory, Samuel Ruben, worked with Kamen and the

radioisotope C¹¹ on the mechanism of photosynthesis. Their discovery of a better tracer, C¹⁴ , was one of the high points of the Laboratory's prewar work.^[142]

Spiralling further out, Lawrence's people had an opportunity, not frequently seized, of easy exchanges with their colleagues at Stanford. When Felix Bloch, a theoretical physicist with the highest European pedigree, took up an assistant professorship at Stanford in the fall of 1934, he and Oppenheimer began joint weekly seminars, three-quarters of which were held at Berkeley. This interchange resulted in collaborations between Bloch and Oppenheimer's students and between Bloch and Alvarez, and in the inspiration for an investigation by Laslett. The work of Alvarez and Bloch on the magnetic moment of the neutron was probably the most advanced piece of exact physics done at the Laboratory during the 1930s. Stanford also offered the advantage of a summer course by a visiting theorist; we do not know how many of Lawrence's people besides Nahmias took the opportunity or trouble to go to Stanford to hear Gamow, Victor Weisskopf, Rabi, John Van Vleck, or Fermi. Nor have we been able to trace much useful interaction where it might be expected, between the Berkeley cyclotroneers and the applied physicists in and around Stanford, William Hansen and the Varian brothers. These men also had an interest in accelerators, but for electrons, not ions. Their "rhumbatron" and "klystron," which did not interest Lawrence in the late 1930s, came to play a part at Berkeley during the war.^[143]

In Partibus

We count that the Laboratory had some fifty-four regular members from 1932/33 through 1939/40, "regular" meaning, for our purposes, persons working to prepare for a career in science.

Established people, who came on sabbatical or fellowship leave, volunteers without career ambitions, and undergraduates who left without obtaining a degree, do not count as regulars. The fifty-four distribute into two groups in two different ways: (A) graduate students who obtained a Berkeley Ph.D., not necessarily by 1940; (B) people who came as fresh postdocs; (I) members of either group who left the Laboratory before the war; (II) members of either group who returned to, or remained in, the Laboratory for war work. The numbers involved appear in table 5.5. Half the Ph.D.'s and three-fifths of the postdocs, some twenty-nine people in all, made up the Laboratory's export of manpower during the 1930s. Of these, two out of three went to build or perfect cyclotrons elsewhere: they are our "cyclotroneers in partibus." They and their destinations are listed in table 5.6.

The first of the agents or disciples in partibus was Livingston, who styled himself a missionary and was expected to effect a miracle. In 1934 the Cornell physics department had just fallen under

the control of R.C. Gibbs, an ambitious and prescient man, who decided to plant nuclear physics in Ithaca in the hope that a flourishing research tradition would grow in its shade. He brought in Livingston and, the following year, Bethe, as assistant professors to cooperate in establishing a theoretical and experimental program in nuclear physics. They did so successfully; but it proved impossible to continue development of even a sixth-scale version of the Berkeley Laboratory. The fundamental obstacle, which all cyclotroneers encountered in one degree or another, was lack of staff. Crew service had no appeal high above Cayuga's waters. Furthermore, although Cornell warmed to the cyclotron gospel, Gibbs had other interests to further as well and his even-handed

division of departmental assets hampered the expansion of capital-intensive units.^[144] Therefore, although Livingston built a small and effective cyclotron in good time (it gave 3 or 4 µA of 2 MeV protons within a year), and although he and Bethe worked productively together, he felt stifled as a cyclotroneer. As far as cyclotrons are concerned, as Lawrence was to say, "the larger the better." In 1938 Livingston went to MIT as associate professor of physics to build a cyclotron larger than Berkeley's 37-inch.^[145]

The problem of understaffing was met in part by collecting more than one man with Berkeley experience at one place. That occurred with the second cyclotron built outside the Laboratory, at Princeton, by Milton White and Malcolm Henderson; it, too, took about a year to make, but, unlike Livingston's machine at Cornell, it was larger (36-inch poles) than its original when it came to life in 1936.^[146] Other examples of double teaming:^[147] the machines built or started by Berkeley pairs, as at Illinois (the second cyclotron there), Indiana, and Saint Louis; machines begun by visitors to the Laboratory and finished by regulars, as at Chicago, Harvard, Michigan, and Rochester; machines started by foolhardy types without Berkeley experience and finished with the help of one or more men from the Laboratory, as at Cambridge, Columbia, Copenhagen, Liverpool, and Paris. The mutual dependence of these young men entrusted with large and costly projects comes out eloquently in a late night letter from Thornton, then at Michigan, to Cooksey. "There are so many things under way my nerves get on edge and I am pursued by doubts. Reg [J.R. Richardson] is a great help in really discouraged moments—someone to chew with, with a proper flippant attitude towards cyclotrons."^[148]

Most cyclotroneers in partibus had to adjust their rates of performance and their levels of expectation. No one worked to Lawrence's pace. "It does take more time to get things done here in the East," Livingston discovered, pointing to a lack of "the complete stock of small things such as wires, insulation, adaptors, etc., that make things move so fast at Berkeley." Exner contrasted "the California habit of speed" with "the lethargic East." "If I haven't written you before," White wrote from Princeton, "that is because I am ashamed of the lack of progress here." The Laboratory ran almost at full tilt during summers; it came as a great surprise to Lyman, when he arrived to take up his job at Illinois in August 1938, that the physics department was closed. "The deadest place you have ever seen. . . . They take their vacation seriously around here."^[149]

The men who went to help finish cyclotrons abuilding on the Continent expressed a double culture shock. Laslett, in Copenhagen: "Here things seem to be taken with reasonable calmness and if I work at night until . . . say 10:00 P.M., I feel like a scab in a fink joint." Taking things calmly, Laslett went on vacation with Otto Frisch, who was expected to be the director of the Copenhagen cyclotron. It was not Frisch but Laslett who felt obliged to cut short his tour to try a new improvement on the machine. The metabolism of the Danish physicists ran at a Berkeley pace, however, in comparison with the pulse in Paris, where Paxton found his colleagues harder to move than their 30-ton magnet.^[150]

The ex-Berkeley cyclotroneers formed a brotherhood, to use White's word. The European branch—Sten von Friesen, Hurst, Kinsey, Laslett, Walke—met in England, then in Denmark and Sweden, and planned a session in Lapland. The midwestern brotherhood—those at Chicago, Illinois, and Indiana—exchanged visits and provided overnight stops for Lawrence or Cooksey, hurtling East or West. The brotherhood on the Atlantic seaboard—

those at Bartol, Columbia, Harvard, MIT, and Princeton—were the ciceroni on a standard cyclotron tour.^[151] In Livingston's analogy, the cyclotron laboratories were like the California missions; located from the Midwest eastward at convenient intervals, they assured travelling cyclotroneers a welcome and a place to stay or work. When the Great Cyclotroneer himself appeared, miracles occurred: Lawrence could cure machine ills and clear up financial and personal difficulties that had refused to yield to lesser medicine. For sinners who had tried on their own and failed, the mother church had a particular indulgence. "They are like babes in the wood," Cooksey wrote of the builders of the Purdue cyclotron, who had never seen the inside of one before beginning their labor, "and need a visit."^[152]

These visits promoted more than camaraderie and nostalgia. Cyclotrons multiplied in part because Lawrence wished them to. "It would please me greatly," he wrote in answer to Columbia's request for his "fatherly blessing" on their project, "if various laboratories would build cyclotrons." It was the Laboratory's policy, as Cooksey put it, to be "most interested in giving what information it can to help those who are starting in this fairly new field."^[153] A large portion of the very large correspondence of Lawrence and of Cooksey during the late 1930s is devoted to what the builder of the Yale cyclotron called "the usual generosity," that is, answering questions from perplexed or would-be cyclotroneers; providing blueprints of Berkeley machines and accessories to any laboratory seriously engaged in planning or building cyclotrons; lending or giving old parts. And they could do more. To assist Bohr and Joliot, Lawrence helped to obtain fellowships from the Rockefeller Foundation for Laslett and Paxton; to help the Japanese, he and Cooksey arranged for the delivery and machining of the steel and copper for the second Tokyo cyclotron.^[154] The cyclotroneers in partibus shared this ethic. Ignorant

of or indifferent to the patent situation, they exchanged information freely among themselves and continued to contribute to the advance of the art at Berkeley by trying new techniques on their own machines. Several major improvements came forward in this manner, in particular the capillary source introduced by Livingston and tested at Princeton and Rochester and the quarter-wave transmission line pioneered at Illinois and Columbia.^[155]

Although cyclotroneers worked in many environments much different from Berkeley's, they often enough were supported by the same means as Lawrence had dispensed. The federal government assisted elsewhere as it had in Berkeley. The navy gave generators and the 500-kilowatt Poulsen arc for which Cornell and Columbia competed; had the navy had more to distribute, the union of the arcs with experts from Berkeley would no doubt have made the country (to use the elegant phrase of a Westinghouse engineer) "lousy with cyclotrons." The quantity of gifts in kind to accelerator laboratories from the navy and the War Department got a high reading on the Nahmias detector: "[They] continually distribute many pieces of equipment: generators, pumping systems, copper, electromagnets, oil, rectifiers, etc., to everyone who knows how to wangle them." Columbia's successful wangle, to meet the navy's requirement that the Poulsen magnet serve vocational education, is worthy of attention: "The magnet will be used by graduate students in connection with their training in research . . . ; such training is strictly vocational as opposed to general cultural education."^[156]

Opportunities for vocational training spread with the help of the foundations. After the National Research Council had played a brief and inexpensive part in Cornell and Illinois, the Research

Corporation, with its eye to the patent situation, made a series of grants of $2,000 or $3,000 to start or improve cyclotrons. Among its beneficiaries were Chicago, Columbia, Cornell, Purdue, Rochester, and Stanford.^[157] By 1939, however, the Corporation had sensed that there was little for it in the "mad, but orderly scramble" to multiply cyclotrons within the same energy range and it concentrated its diminishing investments in accelerators on a bet on Berkeley.^[158] The enlargement of opportunity and costs attendant on radioisotope manufacture brought substantial contributions from the Rockefeller Foundation to cyclotron building in Copenhagen and Paris, and lesser amounts to Rochester, Saint Louis, and Stanford.^[159] Like the Research Corporation, however, the Foundation apparently decided not to support new machines within established energy regions. In 1939 it had the courage to turn down Harvard's request for "a substantial annual grant for a period of years," much to the surprise of president Conant, who had sunk money in a medical cyclotron expecting that it would bring in foundation money easily.^[160]

MIT tried the National Advisory Cancer Council, without issue, and then did very well at the Markle Foundation, with $30,000. Michigan tapped its Rackham funds, an endowment given by an organizer of the Ford Motor Company, for some $25,000 a year, which made Michigan the richest American cyclotron laboratory outside Berkeley. But the brotherhood did not live by bread alone; and something in the air at Michigan drove away the two

Berkeley cyclotroneers, Thornton and Richardson, who started their extramural careers there.^[161] To finish our parallels, had Lawrence had his way, the National Advisory Cancer Council would have given all the American cyclotron laboratories in existence in 1938 save Bartol, which he thought sufficiently supported by Dupont, enough to realize their potential for radioisotope production or medical therapy. No more than the Research Corporation or the Rockefeller Foundation, however, did NACC wish to dribble away its resources to a large number of equivalent laboratories.^[162]

It is not practicable to learn how much of the cyclotroneers' salaries was paid by the various contributors to cyclotron laboratories, or, indeed, the magnitude of the contributions. But we can make a rough estimate of the capital investment, inclusive of labor, in American cyclotrons operating outside Berkeley by 1940. These machines cost or represented about $250,000 exclusive of the value of the buildings that housed them. With these structures they came to about $400,000. The cost of their operation from the time of their commissioning through 1940 would perhaps raise the total expenditure on them to something like the amount spent on cyclotrons at Berkeley during the 1930s.^[163]