Working at a faster pace than the United States because of the immediate threat to their security, the British had developed a system of radio detection by a pulse method, and the first experimental system had been set up on a small island off the east coast of England. Between the fall of 1935 and 1938, a highly efficient system of radar stations, called the Chain Home network system, was erected to give advance warning of approaching aircraft. By September 1940, the Chain Home system had been in operation against the enemy for over a year and was at that very moment helping the British pick off German planes as they streamed over the English Channel. Combined with their quick-response fighter units, the British were tearing up Hitler’s forces.
The U.S. Joint Chiefs of Staff were floored by the reports that the air warning system was proving a decisive factor in the Battle of Britain, from which England was already emerging as a victor. When the air assault had begun earlier that summer, the Germans had been repelled with heavy losses, in no small part because the British were forewarned of each assault by their radar detectors and could order their Spitfire and Hurricane pilots into the most advantageous position to intercept them. It was impossible for the American military leaders not to be deeply affected by the facts laid out before them—radar was emerging to all the world as a vitally important weapon of war. As a direct result of those first meetings, the top army and navy brass took immediate steps to bring their long-range radar (at the meter wavelength) up to speed and introduced into service.
The British had not revealed their most valuable secret, the existence of the magnetron. It had been hinted at, and the possibility of generating substantial pulse power at short centimeter wavelengths had been suggested, but the mysterious device that could achieve this had not yet been described. When Bush and Tizard had first met on August 28 at the Cosmos Club, the highbrow Lafayette Square meeting place, Bush recalled the delicate tap dance they both kept up, as there were still many bureaucratic stumbling blocks to free discussion. While waiting for the army and navy to obtain official authorization for the NDRC to talk to the British, Bush arranged frequent meetings with his British counterpart “behind the barn”:
We were rather careful not to seen together too much for fear that some people in Washington would conclude that there was some sort of conspiracy under way. Both Tizard and I were in something of a quandary, for each of us would have liked to have told our own group that the other had made very significant advances which would be valuable, but we could not do that as we were both of us under severe limitations. I think you can well imagine the skill with which Tizard handled the affair, making contacts with dozens of people and giving the impression, without saying anything definite whatever, that Britain had made an extraordinary advance. . . .
It was only natural that the American military officials were, at the start, doubtful as to whether the British were “putting all our cards on the table,” as Cockcroft put it. There was a deep-seated conviction of technical superiority on both sides and a shared suspicion that the other was withholding some secrets. Cockcroft used his long-standing friendship with Loomis and Lawrence to try to establish an atmosphere of greater trust and warmth. By special arrangement, Cockcroft and the members of the Tizard Mission were authorized to brief civilian scientists like Loomis on the same basis as top military officers.
On the evening of September 11, Loomis invited the Tizard Mission to an informal evening conference at the Wardman Park Hotel, a short walk from their headquarters at the Shoreham. Loomis began by outlining everything his panel had been doing in the microwave field. He filled them in on the recent tour of industrial laboratories working on microwaves he and Compton had conducted that summer, detailed which research facilities they would be advised to visit, and invited them to Tuxedo Park to see what was being done in his own laboratory. He also explained the progress that had been made in transmitting and receiving tubes at wavelengths around forty to fifty centimeters, which outstripped what they were doing in Britain. But in the very short wavelengths, they had yet to find their way past the same obstacle that had once stalled British physicists—namely, the lack of a high-power oscillator.
When the British expressed their interest in microwave radar, Loomis reacted with great enthusiasm. The standard radar sets used by the United States Army and Navy all operated on the same relatively long wavelength of one to two meters, with correspondingly broad beams. Similarly, the Chain Home stations were large installations with the massive reflectors needed to accommodate the ten-meter wavelengths the system used. Bowen, who had spent the previous five years setting up those reflectors in some of the most barren, godforsaken spots on earth, appreciated the American’s recognition of what they had accomplished. At the same time, Loomis grasped the considerable military advantage that could be had in developing the still primitive radar technology in the very short “microwave,” or ten-centimeter wavelength, range, which would allow them to gauge the enemy position more accurately and distinguish among tightly bunched targets. The young physicist took an immediate liking to Loomis—he was unquestionably an original and stood apart from the others in the room. He was also openly and resolutely in favor of helping Britain win the war, which permanently endeared him to the Welshman.
After the dinner, they retired to the large suite Loomis kept at the Wardman Park for just such occasions. The American military officers were surprisingly reticent. The attitude of one admiral, in particular, struck Compton as very “anti-British,” and he appeared to spend a good part of the evening becoming conspicuously drunk, which Compton suspected was “a dodge” to avoid giving Tizard any more information than necessary. Loomis, on the other hand, established an easy rapport with Tizard, whose background in many ways mirrored his own. They both belonged to their country’s elite and possessed the skilled, patient, genial manner that disguised a razor edge. Both had worked in research and development during the previous war; and what Loomis had done for gunnery at Aberdeen, Tizard had accomplished in improving the technology of British aircraft. In a room filled with stuffy admirals and generals from both sides of the ocean, the physicists felt a strong sense of camaraderie, bolstered by their mutual confidence and admiration. The nucleus of a powerful alliance had been established.
Before the night was out, despite what Cockcroft felt to be a “rather doubtful opening,” the British quietly revealed the magnetron to the small party of Americans in Loomis’ suite. Looking from face to face, Bowen could see they were stunned to learn that it could produce a full ten kilowatts of pulsed power at a wavelength of ten centimeters. “The disclosure was the key point,” recalled Cockcroft. “From then on we had no difficulties.” The decision was quickly made that an American team should start at once on the development and production of ten-centimeter radar based on the British magnetron, for use both on the ground and in the air. The army and navy opted to proceed with the development of their own longer-wave radar systems, and Loomis and his newly formed microwave committee took responsibility for pursuing the experimental short-centimeter waves. In the days that followed, Tizard formalized these arrangements with Bush, and Bowen and Cockcroft made preparations for the crucial meeting with the microwave committee to be held that weekend at Loomis’ place in Tuxedo Park.
On the morning of Saturday, September 28, Bowen and Cockcroft flew to La Guardia Airport in New York City, where they were met by one of Loomis’ chauffeured cars and ferried in grand style forty miles to Tuxedo Park. The leaves were at the height of their autumn glory, and the two British scientists admired the colorful display bursting from the elms, oaks, and maples lining the long, twisting road that led up through the hills to the mansion-cum-laboratory. Loomis greeted them and took them on a tour of Tower House and a second structure he called his “playhouse,” which Bowen recalled as an ultramodern building with full air-conditioning and “automatic everything else.” That afternoon, they all drove to Bendix Airport, and before a group consisting of Bowen, Cockcroft, the MIT radar specialist
Ed Bowles, and Carroll Wilson, Bush’s executive secretary, along with several military and naval officers, Loomis staged a field demonstration of his ten-centimeter Doppler radar system, which easily detected a small two-seater plane at a range of two miles. While several of those present had never seen a working radar set before, Loomis was already aware that his device had been rendered obsolete by the magnetron. Afterward, at a meeting at the Tower House, he informed them about the microwave work being done at Berkeley and explained the possible uses of radio yttrium for “intelligence purposes,” outlining the use of a small portable Geiger counter that he had helped develop. The British were encouraged by what they had seen, and Bowen cheerfully recorded in his notes at the end of the day that “Dr. Loomis” had organized “a powerful and energetic group, and it should be of great potential help to us.”
The following evening, the two British scientists finally unveiled their prize, the secret invention they had kept successfully from the Germans and had shepherded across the ocean to bestow on the Americans. In Loomis’ elegantly appointed sitting room, Bowen and Cockcroft produced a rough wooden box and unfastened the thumb screws that secured the lid. “The atmosphere was electric,” Bowen recalled, as he slipped out the coppery disk that fit neatly in the palm of his hand. “They found it hard to believe that such a small device could produce so much power and that what lay on the table in front of us might prove to be the salvation of the Allied cause.”
Cockcroft brought out the blueprints, complete with drawings and construction details, and spread them out on the floor. During the conversation that started that night and continued the next morning, Bowen and Cockcroft explained how the magnetron “opened up new vistas” and “increased the power available to U.S. technicians by a factor of 1,000.” They also explained their objectives in radar, specifically the critical importance to their defenses of microwave airborne radar sets—the one piece of equipment, above all others, that could transform their defense against the night bomber. It would also enable the RAF’s bombers to navigate the dense cloud cover that often obscured German fighter planes right under their noses and allow them to target factories and forces on the ground with far more accuracy. British planes equipped with extremely short centimeter radar would be able to detect U-boat periscopes piercing the fog, which was like picking a needle from a haystack for the longer-wave systems. Ed Bowles could scarcely believe what he was hearing: “All we could do was sit in admiration and gasp.”
Loomis’ excitement mounted as the magnetron’s mode of operation and capabilities were explained. With a surge of excitement, he realized that here was the opening he had been looking for. The moment the British put the magnetron on the table, he knew “a major breach had been made.” The klystron, which had been their best bet, could never be a high-powered oscillator. “This was the first fortunate break, for the magnetron itself had been hit upon by accident by Oliphant and his men.” It changed everything. They now had a technical advantage over the Germans that they had to exploit immediately. As a veteran sailor, Loomis knew how important the element of luck was in deciding the outcome of any race: “The boat ahead gets the new breeze first, just because it is ahead, and thereby increases its lead.” And this was one lead they could not afford to squander.
According to Cockcroft, right then and there Loomis proposed the idea of establishing a large central microwave laboratory. The British enthusiastically seconded the idea, and it was quickly agreed that it should be a civilian rather than military operation, staffed by scientists and engineers from both universities and industry, based on the British model of successful research laboratories and, not coincidentally, Loomis’ own enterprise. Loomis suggested that the laboratory be based in Washington and run under Bush’s auspices at the Carnegie Institution’s Department of Terrestrial Magnetism. The new lab should begin work at once on the development of new ten-centimeter radar systems based on the magnetron.
What had begun as an introductory meeting the night before had by early morning evolved into a strategy session. Loomis called for a luncheon meeting to be held the very next day in New York, on Monday, October 1, to be attended by those members of the microwave committee who were not present. The magnetron was the break Loomis had been waiting for, and he was determined to make the most of it, even if it meant using all the reserves of American industry and science. It became, at once, the focus of Loomis’ whole being. According to Bowen, they then spent hours burning up the phone lines as dozens of people were told what had transpired and where to report the next day: “I have no doubt that the New York Telephone system did an unusual amount of business that night because by the time Cockcroft and I left Tuxedo Park the next morning the Bell Telephone Company had been told that if the Boot and Randall magnetron came up to expectations, they would be given a contract by the Microwave Committee for a small production batch.”
The two British physicists were overjoyed. Up to then, only twelve models of the magnetron had ever been made. Now it was to be put into production and could make a critical difference in almost every theater of the war—on land, in the water, and, most important, in the air. Finally their RAF fighters would be given a way to combat their chief menace, the night bomber. When Tizard was informed of what had been decided at Tuxedo Park, he was delighted. “Push it for all you are worth,” he told Bowen on October 2 before flying out of New York by Pan Am Clipper, which would take him to Bermuda and then via the Azores to London. In spite of the tight security surrounding the mission, he was caught by photographers at the airport.
Later that day, Loomis called on Stimson in Washington to brief him on the dramatic new developments in radar:
Alfred Loomis came in in the afternoon, full of excitement over his interviews with the British and with the scientists, and he was full of the benefits that we were getting out of the frank disclosure by the British to us of their inventions and discoveries of methods they have made since the war. He said we were getting the chance to start now two years ahead of where we were. . . .
The secretary of war was impressed by what he heard. He had already been alerted to radar’s importance in the Battle of Britain by his cousin, but now he called in General Marshall to hear Loomis’ view of the situation:
Alfred was very flattering to the Army on the comparative frankness which we had shown on our part, as compared with the tendency on the part of the Navy to hold back all their secrets, even though the secrets did not amount to much. He said that our frankness had enabled the British to put their hands on the table and had given us a rich mine of information and it has also brought the Navy around to a better state of frankness on their part. Apparently everything is going along well now.
That night, Loomis joined Stimson for dinner at Woodley, the stately eighteenth-century mansion that was only a few minutes’ drive from the old State, War, and Navy Building, next door to the White House, where Stimson kept his office. Several men from the War Department were also present, as were Brigadier Charles Lindemann, an attaché at the British embassy, and John J. McCloy, who had recently left the law firm of Cravath to become one of Stimson’s top aides. McCloy, like most members of Stimson’s inner circle—including First Assistant Secretary Robert Patterson, Assistant Secretary of War Robert Lovett, special assistant George Harrison, and Loomis—was a fellow graduate of Harvard Law School, who had been successful on Wall Street before coming to the War Department. They were all Republicans serving a Democratic president, who, apart from his party affiliation, was very much of the same stripe—the same class, social background, and education. They worked extremely closely together as a team, bound by strong ties of family, friendship, corporate and institutional loyalties, and, above all, their loyalty to Secretary Stimson and the ideals he was fighting for. “We had a very pleasant dinner,” Stimson wrote in his diary of the tight-knit group, which gathered weekly in different numbers at his home, and “afterwards sat around talking, mainly over war problems, until eleven o’clock.”
/> LOOMIS’ microwave committee immediately placed a production order with the Bell Telephone Company for an exact copy of the magnetron. On October 3, the day after Tizard’s departure, Bowen paid a visit to Bell’s headquarters at 463 West Street in New York. A group of Bell’s top researchers were waiting for him and were fairly bursting with curiosity to see the British magnetron, which they had heard about from Loomis. Bowen put the magnetron on the table and took out drawings of the internal construction and manufacturing details. “They were fascinated by the design,” and if Bowen sensed that they had “reservations about the extraordinary output” the British had boasted of, they soon conceded it had “enormous potential.” Not only did Bell’s engineers anticipate no difficulty in copying the magnetron, they wanted to begin right away. If the device lived up to its promise, they would be awarded the plum manufacturing contract. Since it was advisable to first conduct a test run, arrangements were made to meet the following Sunday at Bell’s Whippany laboratories in New Jersey, where they had a pulse generator and the requisite voltage.
Bowen left the magnetron in their care, and he and Cockcroft kept to a grueling schedule, visiting the laboratories Loomis had recommended, beginning with RCA and MIT, and later General Electric, Western Electric, Sperry, and Westinghouse, among others. At each stop they doled out just enough technical information to leave their audience intrigued and were careful to hold back information on the magnetron, which they were saving for Bell. On Sunday, October 6, Bowen drove to the Whippany laboratories, where several of the senior Bell staff were gathered. As Bowen surveyed the equipment they had dug up, including a large electromagnet of the sort common in university physics departments, he was painfully aware of the fact that the last time the magnetron had been tested was two months earlier back in Wembley. It had traveled three thousand miles, by train, boat, and armored vehicle. “Very gingerly,” he recalled, “we switched on the anode potential and were instantly rewarded with a glow discharge about an inch long coming from the output terminal.” Bowen stared at it, blinking in surprise: “I had not seen anything like this before and we looked at it in amazement.”
Tuxedo Park Page 25
