Hospitalization

Two major research hospitals decided to try what Sloan's tube could do. The first commission came from Francis Carter Wood, the director of the Institute of Cancer Research of Columbia University, who had encouraged Lauritsen's work and knew of Berkeley's alternative through Buffum. The Chemical Foundation dispatched its physicist, Frank M. Exner, to help Sloan build an improved machine, for which Wood's Institute would pay $5,725 from a fund given by Charles Crocker, the son of one of California's railroad barons. How improved? Lawrence told Exner he wanted to push to a million volts; Exner told Wood, and Wood objected. His institute had long experience treating cancer with the gamma rays of radium, at 2 MeV, and they had not "done any miracles." Lawrence thought about it from the "physical point of view" (and also as an entrepreneur with a balky

[48] Lawrence to Poillon, 4 Aug 1932 (15/16), and to Buffum, 25 Aug 1932 (3/38); "Harold" to Tuve, 5 Jan 1931 (MAT, 3), re Westinghouse.

[49] Lawrence to Poillon, 4 Aug 1932 (15/16) and 18 Aug 1932 (RC); Boyce to Lawrence, 27 Jan, and reply, 9 Feb 1932 (12/11), re Livingood.

client) and agreed. "There is not much point in x rays above a half a million volts for therapy purposes."^[50] But the Sloan tube was to be developed for the art, as well as for medicine and patents, and also to support life in the Laboratory. Livingston, having graduated, needed a job to sustain him for his essential work on the cyclotron. Lawrence looked everywhere and found nothing. The obvious solution to all difficulties would be to employ Livingston part-time on x-ray money. The goal would stay a million volts.

Everything fell into place with the commissioning of a millionvolt plant by the University's Medical School. The initiative came from Stone and the money—some $12,000 for plant and installation—from William H. Crocker, brother to Columbia's patron and a regent of the University. Livingston became to Stone's machine what Exner was to Wood's. Therefore he was expected—so flimsy were the professional qualifications of radiologists then—to run it as well as to make it. His relevant training consisted of two weeks with Lauritsen to learn technique. He then set dosages for the human guinea pigs at the University hospital.^[51]

The estimated costs of the twin Crocker machines included no profit, overhead, or salaries. Their 20-kW Federal power oscillators cost $300 each, after a 20 percent discount, and each machine needed four, or, in the new design, six. Economy was necessary. Sloan salvaged a ton of lead plates from old storage batteries, melted them down, and remolded them into shielding blocks. Safety demanded an additional 6,000 pounds of lead, which Lawrence begged as an additional loan from the American Smelting and Refining Company. Efficiency required an instrument maker, whose salary had to be found. To begin development of the hospital machines, Lawrence needed $4,000 immediately, or so he told the Chemical Foundation. His reckoning omitted the salaries of Sloan and Livingood.^[52]

[50] Wood to Lawrence, 29 Aug 1932, and Lawrence to Wood, 3 Sep 1932 (9/21); Lawrence to Exner, 19 Aug 1932 (9/21); infra, §8.3.

[51] Lawrence to Buffum, 25 Aug 1932 (3/38), to Stone, 20 Sep 1932 (16/28), to Henderson, 7 Jan 1933 (9/6), and to Cooksey, 1 Jan 1934 (4/19); W.H. Crocker to Sproul, 11 Jan 1933 (UCPF, 337/366).

[52] Lawrence to Federal Telegraph Company, 8 Sep 1932, and reply, 15 Sep 1932 (7/10); Lawrence to Buffum, 25 Aug 1932 (3/38); to Wood, 3 Sep 1932 and 10 Jan 1933 (9/21); to Boyce, re Livingood, 1 Oct 1932 (3/8).

By December 1932 the prototype hospital machine was working beautifully. It could perform briefly at over a million volts, and at 750 kV gave out 14 milliamps so steadily as to melt its water-cooled copper target. It far exceeded their fondest hopes, Lawrence told Wood, being much superior to Coolidge's cascaded tubes or Lauritsen's set of gas-pump cylinders, and, moreover, compact and inexpensive, like the first cyclotron. It was a light that could not be hidden, the equivalent of half the world's supply of radium. "Though we have most of the tube plastered with lead (7,000 pounds in all), we see x rays almost everywhere in the lab with a fluoroscope." "There is no question now [December 1932] but that we have the most powerful x ray tube in the world and that our outfit is incomparably superior to any other, and promises to revolutionize x ray technology. I say this unqualifiedly."^[53]

This last disclosure was directed to Poillon, who was trying to patent Sloan's invention when he received it. Poillon had not looked upon the work at Berkeley with unmixed satisfaction. It was the old problem with academics: they innovated, jerry-rigged, experimented, always improving and refining, indifferent to the business side of things. "I have told Sloan and Lawrence [Poillon complained to his patent lawyer] that we wanted this device brought to a certain state of perfection at Berkeley, where it could be engineered for production. They seem to be very anxious to get somebody else to do that secondary step. . . . This of course does not suit our book and I have warned them about directing the attention of others to it lest the others start the development and the patent situation becomes very cloudy." Poillon tried to silence the publicity that the commissioning of the hospital plants had generated.^[54]

Poillon's impatience did not deflect Lawrence. Having done the physics, if not the engineering, of million-volt x rays, the Laboratory proposed to replace the heart of the machine, the expensive commercial oscillator, with cheaper devices of its own manufacture. That required patience from Stone and Exner and

[53] Lawrence, "A brief summary of the work of the Radiation Laboratory," attached to Lawrence to Poillon, 5 Jan 1933 (15/16A); quotes from, resp., Lawrence to Cooksey, 11 Dec 1932 (4/19), and to Poillon, 13 Dec 1932 (15/16).

[54] Poillon to A.P. Knight, 11 Oct 1932 (RC); Exner to Lawrence, 7 and 8 Feb 1932 (9/21).

money from Poillon and Buffum. Lawrence asked for $500 to $1,000. Poillon, hard-pressed and unenthusiastic, returned $700. "Money as you know is extremely scarce."^[55] Fuller took over the direction of the project and assigned an engineering student to help design a practical 200-kW oscillator. A satisfactory design emerged, in which the oscillator shared the vacuum of the discharge tube; Lawrence stopped development of instrumentation for the cyclotron and threw his disposable resources into making and improving the new tube.^[56] By June 1933, having spent $550 of the $700, Fuller, Sloan, and company had an oscillator more powerful than Federal's; by September they had licked the remaining vacuum problems; by December Stone's machine was ready for installation, and Sloan, exhausted, was ready for the hospital.^[57]

Livingston and Sloan set up the San Francisco machine (plate 3.4). It performed beautifully, at a lower cost for power than expected. Crocker's $12,000 bought a building ($5,000), the machine ($4,000), Livingston's salary ($1,000), and accessories ($2,000). Running at 800 kV and 10 milliamps, it outdid all other x radiators, including Lauritsen's.^[58] The business was, in fact, a great success. It showed how a subsidized university, with clever men, out-of-work or underpaid postdocs, and, if it wished, no overhead charge, could outdo industry. As Lawrence pointed out, GE had recently built an x-ray unit for a Chicago hospital that cost $65,000, faltered at 600 kV, and took much longer to install than Sloan's machine. GE's standard tubes cost $25,000, Kelley-Koett's 600 kV tubes $29,000. The Crocker brothers got a great bargain.^[59]

[55] Lawrence to Stone, 17 Jan 1933 (16/4); to Poillon, 10 June 1933, and Poillon to Lawrence, 11 Feb 1933 (15/16A).

[56] Lawrence to Poillon, 18 Feb and 14 Apr 1933 (15/16A); to Sproul, 24 Jan 1933 (16/42).

[57] Lawrence to Poillon, 14 Apr, 3 June, 16 Sep, 4 Dec 1933 (15/16A); to Cooksey, 3 May 1933 (4/19); to Exner, 12 Sep 1933 (9/21); to dean, Graduate Division, 16 Nov 1933 (16/27).

[58] Lawrence to Fowler, 28 Dec 1933 (7/2); to Exner, 17 Nov 1933 and 18 Jan 1934 (9/21). Sloan resigned his University fellowship in January 1933 to work on the installation at the Medical School; Birge to M. Deutsch, 7 Jan 1933 (Birge P, 33).

[59] Lawrence, "The Sloan x ray machine" (16/28).

Exner began to set up the Columbia machine after his return to New York in late spring of 1933. He eventually had as his helper Wesley Coates, who had completed his doctorate under Lawrence in 1933 with work on the soft x rays he found in targets struck by fast heavy ions from the old mercury linac. Coates went to Columbia to build a machine on Sloan's principles for the acceleration of protons. He then became the physicist at the Crocker Research Laboratory of Columbia Presbyterian Medical Center, where the Sloan x-ray machine had been placed. One day in 1937 the machine declined to hold its rated voltage. Coates peered in to diagnose the trouble, brushed a high-potential line, and fell a martyr to high energy.^[60]

The Laboratory continued its efforts to improve Sloan's tubes well into 1935. Wood decided that experimentation with rays comparable in penetrating power with radium's gammas might be valuable after all and made available ample funds for building oscillators large enough to drive the tank at the highest voltage it could take. He paid salaries to Sloan and the instrument maker, E.W. Lehmann, and various shop costs, amounting to upward of $1,700.^[61] During this work, Dr. Walter Alvarez of the Mayo Clinic came to town. Lawrence took him to the University's Medical School. "He was exceedingly enthusiastic about it," Lawrence wrote Poillon, "and wants to start negotiations." Lawrence urged the Research Corporation to greater activity: "There is absolutely no question but that you should push the commercial development as rapidly as possible."^[62] As symbol and agent of this alliance, Lawrence's student Harry White went to work for the Research Corporation after learning to run the Sloan machine in San Francisco in order to promote it "and possibly . . . other by-products of the Radiation Laboratory work in the future."^[63] Several pests then attacked Sloan's x-ray plants. For one,

[60] Lawrence to B. Davis, 5 May 1933, and Exner to Lawrence, 23 Mar 1937 (4/4); Coates, PR, 46 (1934), 542–8; Lawrence to Poillon, 14 Apr 1933 (15/16A).

[61] Exner to Lawrence, 14 Mar and 3 May 1934, and Lawrence to Exner, 21 Apr 1934 (9/21); Exner to Lawrence, 8 Apr 1934 (25/1); Lawrence to Poillon, 30 Oct 1934 (15/16A)

[62] Quotes from, resp., Lawrence to Poillon, 6 Jul and 7 Nov 1934 (15/16A). Another interested party was Allibone; A.P.M. Fleming to Lawrence, 19 Feb 1935 (13/3).

[63] Lawrence to Poillon, 5 and 22 Jul 1935 (15/17).

Berkeley's homemade oscillator appeared to infringe RCA patents; the existing plants switched to commercial tubes, which would have driven the cost of future installations to around $25,000.^[64] For another, Sloan suffered a back injury that made him a semi-invalid from 1935 to 1937 and unable to carry development further.^[65] And another of the Research Corporation's investments, the Van de Graaff generator, showed itself capable of producing million-volt x rays more economically than the Sloan tube.^[66]

As Birge had said, the Laboratory's development of high-voltage x radiators was largely a commercial venture. It was not the sort of thing that won prizes in physics. After crediting the Research Corporation and the Chemical Foundation with the initiative for developing Sloan's ideas into an effective generator of x rays, Lawrence wrote in his report to them for 1932: "From the point of view of physicists the most interesting aspect of the Sloan apparatus is its tremendous effectiveness in producing intense beams of two [!] million volt protons."^[67] In his correspondence with physicists, Frédéric Joliot, for example, Lawrence emphasized not the x rays but the protons; and even when, in justifiable pride, he mentioned the fearsome power of Sloan's first machine, he specified the primary purpose of the second as the creation of milliamps of million-volt protons.^[68] It was the first task Sloan took up after recovering from overwork. By February 1934 he had observed his protons, but not in the numbers desired. It took well into the year before this, the "primary purpose" of his work, was realized.^[69]

[64] Lawrence to Poillon, 15 Mar and 30 Oct 1930, and Poillon to Lawrence, 23 Oct and 15 Nov 1934 (9/21); Exner to Lawrence, 26 Jan 1935 (9/21); Sloan, interview, 6 Apr 1976 (TBL); Lawrence to F.C. Blake, 19 Nov 1936 (16/28), estimating the cost of a Sloan apparatus.

[65] Lawrence to Exner, 31 Jan 1935 and 27 Jan 1937; to Wood, 28 Aug 1935 and 27 Oct 1936 (all in 9/21). Sloan did not recover entirely until 1939; Lawrence to Poillon, 11 Jul 1939 (15/18).

[66] Stone and Aebersold, Radiology, 29 (1937), 297–304; Lawrence to F.C. Blake, 19 Nov 1936 (16/28); J.G. Trump to Poillon, 7 Oct 1936 (15/17), re a 1.2-MV Van de Graaff x-ray machine at MIT.

[67] Lawrence, "A brief summary," attached to Lawrence to Poillon, 5 Jan 1933 (15/16A).

[68] Lawrence to Joliot, 20 Aug 1932 (10/4); to H.A. Barton, 8 Sep 1932 (2/25); to J.A. Fleming, 10 Dec 1932 (3/32).

[69] Lawrence to Exner, 1 Feb 1934 (9/21); Sproul, report for 1932, quoted in Birge, History, 4 , 22.