***
Exactly five weeks before Frankie’s first hungry girl fainted in that twelfth row, John J. McCloy ordered the acquisition of the Los Alamos Ranch School for Boys, where Robert Oppenheimer had been educated as a child, for a special war project. Oppenheimer had recommended Los Alamos because it was isolated, and the other Allied scientists agreed that they must have privacy if they were to stand any chance of building a bomb before the Nazis—a possibility most of them felt was exceedingly remote at the time. By now, late in 1942, the Americans and their refugee colleagues were desperate. They had made little progress on the bomb, despite Roosevelt’s commitment. Allen Dulles was reporting from Switzerland that large consignments of uranium and heavy water were entering the Reich every week. Germany’s atomic physicists were the finest in the world. Moreover, the scientists in America suspected that their own project had been compromised. That autumn two German agents had been picked up in the wild hills near Oak Ridge, Tennessee. How they got there, and what became of them, are questions Washington still prefers to leave unanswered. But coupled with other evidence, it added one more touch of authenticity to the nightmare the physicists then thought they saw in the future: Hitler with an arsenal of atomic weapons and the Allies with nothing.
Of this much they were now certain: such a bomb was practical. The hypothesis had been sound from the outset, but there had been a hitch in its application. In theory, a chain reaction should have developed when neutrons were introduced into a U-235 pile. The neutrons would split the U-235 atoms, each of which would liberate from one to three neutrons—which, in turn, would split more atoms, and so on, until the critical mass was reached. Obviously they couldn’t permit that mass to form in a laboratory; that was why they used graphite, to slow neutrons down while they observed the process. In practice, they found, some neutrons went astray and some were “cannibalized” by the pile. A chain reaction was possible only if successive “generations” of neutrons became larger and larger. This was christened the K factor, otherwise known as “the great god K.” It was reached under the following conditions. If 100 neutrons which had caused fission in 100 U-235 atoms gave birth to a generation of new neutrons, 105 of which were left to cause fission, the ratio would be 105 to 100, and the K factor would have a value of 1.05. The third generation would be 105 multiplied by 1.05, and so on, until the mass was formed. As William L. Laurence put it, “When the K factor is greater than one, the pile will be chain-reacting, as the birth rate will be greater than the death rate.” Conversely, if 100 neutrons produced only 99, the K factor, 0.99, would be inadequate. By purifying the graphite in early experiments, the best they could get in those early months was a birth rate of .87 per 100. Their greatest problem lay in the impurity of the uranium. Dr. Arthur H. Compton called the Westinghouse director of research and—at a time when the world’s total hoard of pure uranium metal did not exceed a few grams—asked him, “How soon can Westinghouse supply three tons of pure uranium?” He heard a gagging sound at the other end of the line, but the firm’s response was an illustration of American industry’s versatility in World War II. Uranium fabrication was stepped up from eight ounces a day to over five hundred pounds, and by November 1942 Westinghouse had delivered the three tons.
The delivery address could hardly have aroused less interest. On Ellis Avenue in Chicago, between Fifty-sixth and Fifty-seventh streets, the ivied Gothic walls of University of Chicago buildings parted to reveal a recess and, within, a door. Beyond that door was a large squash court which had been unused since the outbreak of war. The court lay directly beneath the west stands of Stagg Field, and scarcely anyone had come this way since the university had abandoned intercollegiate football. It was there, that November, that a pile of unprecedented size was being assembled with materials of unique purity. Two carbon companies, working with the National Bureau of Standards, had turned out a graphite highly resistant to neutrons. Other bureau scientists had joined Professor Frank H. Spedding of Iowa State College in further improving the Westinghouse uranium; in the new method the metal was transformed into lumps called “Spedding’s eggs.” Lastly, engineers were prepared to create a vacuum in the pile—by enclosing it in an enormous square balloon and pumping the air out—to prevent neutron absorption by nitrogen. Dr. Compton predicted that the new mass would yield a K factor “somewhere between 1.04 and 1.05”; others believed it might reach 1.07.
So great a prospect of success raised new questions. Atoms had been split before, but no one in history had ever created a viable chain reaction, and it was impossible to gauge the efficiency of decelerating techniques. The great god K might defy their checks and restraints, might break loose and take all Chicago, or even Illinois, with it. To reduce the risk, seven strips of cadmium and three rods of boron steel—cadmium and boron being gluttonous consumers of neutrons—were passed completely through the pile; sliding them in and out was expected to give the Frankensteins control over the monster they were creating. No one could be sure that would be successful, however, so two young physicists volunteered to form what was called the “suicide squad.” The two would stand on scaffolding overlooking the pile with buckets of cadmium solution in their hands. If all other controls failed and the apparatus started to go, they would hurl the liquid at it.
Layer after layer was added, and the speed of neutron counters grew with the pile, until, during the bitterly cold night of December 1–2, 1942, the twelfth layer was in place. The contrivance now weighed 12,400 pounds, and the rapid clicking of the counters was unmistakable. “We knew then,” W. H. Zinn later told William L. Laurence, “that if we pulled out the control rods, the thing would pop.” At 3:30 the following afternoon, with Fermi present and the suicide squad in position overhead, all the controls except one cadmium strip were removed; then that was partly withdrawn. The counter clicking was so intense that it reminded one of the witnesses of a burring drill. The K factor mounted to 0.98, 0.99, 1.00—and then 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, and 1.10. They had done it: each successive generation of neutrons would now exceed the last. Pure science had gone as far as it could. The chain was now self-perpetuating; transforming it into a deliverable bomb had become a technological problem.
On that same December 2, the technological issue was being discussed only three blocks away, in room 209 of the university’s Eckhert Hall. Neither group was aware of the other’s presence in the city. Security was very tight; Roosevelt wanted it that way. The President’s attitude toward the Manhattan Project was ambivalent, and, like so many of FDR’s traits, a reflection of the American national character. Instinctively he trusted people, enjoyed sharing knowledge, and wanted the United States to contribute toward the world’s store of learning. But while he spoke of brotherhood—and meant it—he also liked secrets. As James MacGregor Burns has noted, “If Roosevelt was both realist and idealist, both fixer and preacher, both a prince and a soldier, the reason lay not only in his own mind and background, but also in his society and its traditions. Americans have long had both moralistic and realistic traditions.”
In Chicago the President was being realistic; the squash court and Eckhert Hall might as well have been separated by a continent. Nevertheless, they were part of the same design, destined to merge in a B-29 bomb bay thirty-one months later. General Groves had called them here to review the Chicago Metallurgical Project. They were America’s technological elite—captains of heavy industry, professors from Cal Tech and MIT—and the general was asking them to take a lot on faith. They were being asked to produce material they had never seen for a purpose unknown to them. Their only assurances were that the project was vital to the war effort and that Washington would pay the bills.
They agreed, and beginning that month, contracts were signed with clauses which must surely rank among the vaguest in industrial law. Groves pledged four hundred million dollars for a down payment; the ultimate cost would exceed two billion. Beyond that the contractors knew very little, and the few who had to be to
ld certain secrets were forbidden to mention them even to their wives. They couldn’t talk to the scientists because the scientists had, in effect, been removed from society; all their families knew of them was an address: U.S. Army, Post Office Box 1663.
The secrecy seemed excessive to the physicists working at Los Alamos. Certainly some aspects of it seem to have been absurd. The man most closely watched was J. Robert Oppenheimer, and the man watching him was one Boris Pash, an overweight former football coach at Hollywood High School whom the Army’s G2 had transmogrified into a specialist in “Communist infiltration.” Pash fixed his professional eye on Oppenheimer when he heard that the scientist had contributed generously to liberal causes before the war and had twice been on the verge of marrying Dr. Jean Tatlock, a San Francisco psychiatrist who was also a Communist. In 1943 Oppenheimer picked Jean up at her Telegraph Hill home and took her to the Top of the Mark for a drink. He told her that he would be unable to see her again for months, perhaps years, and that because his work was classified he couldn’t tell her what it was or where he would be doing it. Then he disappeared. Seven months later, despairing of ever seeing him again, she committed suicide. Pash, meantime, had shadowed them in San Francisco and had completely misinterpreted their meeting; he thought Oppenheimer had been slipping secrets to a fellow Commie. Telling his superiors that he was on to Oppenheimer’s little game, he demanded that the physicist be fired. Groves replied that this was impossible: “Irrespective of the information you have concerning Mr. Oppenheimer, he is absolutely essential to the project.”
All this might be dismissed as low comedy were it not for the uncomfortable fact that real Communist spies, following instructions from Moscow, were casting a highly professional espionage net around Los Alamos. The control was a certain Anatoli A. Yakovlev, who operated out of New York’s Soviet consulate. Yakovlev worked through Harry Gold, a Philadelphian and a former industrial spy. Another thread in Yakovlev’s web led from Julius and Ethel Rosenberg in New York to David Greenglass, Ethel’s brother, who as a privileged Army enlisted man at Los Alamos had access to almost every blueprint, sketch, or valuable document and was bright enough to know which would be most valuable to Russians interested in building a bomb of their own. Greenglass wasn’t Yakovlev’s prize, though. The real treasure was Klaus Emil Fuchs. Fuchs, like Oppenheimer, Compton, and Fermi, was a highly gifted atomic physicist—a member of the Los Alamos inner circle. A native German, he had fled to England when the Nazis started rounding up their enemies. His hatred of Hitler and his loyalty to the Allied war effort were never questioned, and as a naturalized subject of the United Kingdom he had been granted top clearance. Nobody had asked why the Nazis had been after a theoretical physicist; such questions weren’t raised then. Only after the war, when the Soviet apparatus came apart, would Fuchs’s friends learn that he was a whole-souled Communist.
Usually Harry Gold let other carriers pick up data from Greenglass, but he often met Fuchs, and on one trip he saw both of them. His call on David Greenglass and David’s pregnant young wife Ruth has been memorialized by the top of a raspberry Jell-O box, just as the Hiss-Chambers case would be remembered for a pumpkin. Julius Rosenberg had torn the Jell-O top in half and given one piece to his brother-in-law, David. When a man bearing the other half appeared, Julius had said, David should tell the man everything he knew, in the interest of “sharing information for scientific purposes.” Gold was therefore welcomed to the Greenglass flat upstairs at 209 North High Street, Albuquerque, when he said, “Julius sent me,” and produced his half of the box top. David dutifully produced a sheaf of paper upon which he had set down the best information he could get. It was very good: working in the smallest of the top-secret technical shops at Los Alamos, he had copied several schematic drawings of flat-type lens mold experiments for detonating an atomic bomb. This device bore little relationship to lenses as laymen know them. It was a mix of high explosives which would focus detonation waves as a glass lens focuses light waves, thus triggering the bomb. In Russian hands it would permit Soviet scientists to skip an expensive and time-consuming experimental stage. When David Greenglass put those sketches in Harry Gold’s hands, he was making history. He was also opening his wife’s eyes. Until that moment he had persuaded Ruth that in some obscure way they really were sharing information for the good of all mankind. But when Gold handed David an envelope bearing $500 in cash, her illusions vanished. After their visitor had left she cried, “Now I see how it is: you turn over the information and you get paid. Why, it’s just—it’s just like C.O.D.!” The weakest link in the Los Alamos to Moscow chain had just been formed.
Gold had brought no money for Klaus Fuchs. He had offered him $1,500 last time, and Fuchs had politely declined it. He wasn’t a man to be bought; he was betraying the bomb project on principle. In Santa Fe Fuchs picked Gold up on Alameda Street, as arranged, and took him on a country ride in his battered Chevrolet coupe. When they parted, Gold was carrying a thick packet of typed notes on the application of theoretical fission to the building of a bomb. It was highly technical, way over Gold’s head, but Moscow was elated. The information from both sources, Yakovlev was instructed to tell Gold, was “particularly excellent and very valuable.” Six years later a production chief of the Atomic Energy Commission was shown duplicates of the Greenglass sketches. He said, “Why, they show the atomic bomb, substantially as perfected!”
How much this apparatus helped the Soviet Union when it was supplemented by data from Morton Sobell and Alan Nunn May, two other spies, is a matter of conjecture, even among scientists. It was all a question of time. The Russians had the theoretical knowledge and the technologists; sooner or later they would have found the great god K. Greenglass may, in fact, have given them nothing at all. There was really only one way to build the bomb. Edward Teller described its most intimate mechanism—two hemispheres brought into contact until the mass reaches the critical point and detonates—in an early Los Alamos seminar. Beyond that lay a farrago of details: the amount of U-235 needed, the size of the two halves, the speed with which they must collide, the scattering angle, the range of the neutrons to be projected by the chain reaction, and so on. It seemed endless. It was certainly dangerous. Dr. O. R. Frisch, Lise Meitner’s nephew and the supervisor of this task, nearly lost his life in one experiment, and two other physicists were in fact killed.
Luckily for those working near Harry Dagnian, the first of them, he was holding only a small amount of fissionable material when he accidentally set off a chain reaction. It lasted only a fraction of a second and he was instantly hospitalized, but his right hand had been saturated with radiation. Within an hour he had lost his sense of touch. Gamma rays had penetrated his skin; his viscera were deteriorating. He became delirious, his hair fell out, the white corpuscles in his blood increased, and he died in agony. After that the tensions in Frisch’s labs increased perceptibly. Indeed, the entire settlement was on edge, especially when a carefree young Canadian named Louis Slotin was looking for “the crit.” Slotin was literally playing with cosmic fire—he called it “twisting the dragon’s tail”—and if he had been guilty of a really big blunder, no one would have survived to tell of it. Los Alamos would have been annihilated, Hiroshima and Nagasaki spared, and history greatly altered.
Slotin was an adventurer and a follower of causes. He had fought with the Loyalists in Spain and with the RAF during the Battle of Britain.
Grounded for nearsightedness, he had drifted into the Manhattan Project because he had the right scientific training. Under Frisch he found his métier, though many of his associates ardently wished he were back in a Spitfire. He would tinker away with two live hemispheres, using screwdrivers to slide them toward one another on a rod while he watched, engrossed. It was like Russian roulette. Sooner or later the law of probability would claim its own and he would neglect to separate the halves in time. It happened. One day a screwdriver slipped. The hemispheres came too close to one another; the lab was filled with a blinding blue
glare. He tore the halves apart, breaking the chain and saving the community. He knew that in the process he had forfeited his own life. On the way to the hospital with a friend who had been working near him, he said, “You’ll come through all right. But I haven’t the faintest chance myself.” After nine days of suffering he died. The man assigned to study the incident and ascertain what, if anything, could be learned from it, was Klaus Fuchs.
Most other physicists grumbled about security arrangements—Niels Bohr never became accustomed to his code name “Nicholas Butler” and kept forgetting it—but Fuchs, who knew the real joke, said little. Or rather, Fuchs knew half the joke. The Germans remained an enigma. Hitler kept talking about secret weapons, and early in 1944 he unleashed three of them: jet aircraft, snorkel submarines, and his V-1s, the first buzz bombs. None of the intelligence coming from the Reich undercut the original hypothesis of the scientific community in America. Either Hitler had a bomb, they reasoned, or he was about to get one. He might have an arsenal of them deployed as his last line of defense. The man was capable of anything. Today it is impossible to re-create the terror, hatred, and awe that the German Führer roused; yet without a semblance of it, the motivation of the atomic scientists in the New Mexico desert remains obscure.
The Glory and the Dream: A Narrative History of America, 1932-1972 Page 47
