4. The discovery of nuclear fission, and the bomb reimagined

As the doctrine of air power evolved toward the targeting of civilians, and as weapons to be dropped from aircraft became more powerful, so did the refugee scientists, at Cambridge and elsewhere in Great Britain, come to discover that the awesome power of the atomic nucleus might ultimately be of interest to those with seemingly more prosaic strategic and military concerns. Weaponized atomic energy was not, as it turned out, mere ‘moonshine’ or H. G. Wells’s fictional Carolinum. Nuclear research continued throughout the 1930s at an astonishing pace. In 1934 Irene Curie and Frederic Joliot made radioactive isotopes from ordinary stable elements by blasting them with alpha particles. The same year, Enrico Fermi, in Rome, switched from alphas to recently discovered neutrons and had even better success producing isotopes, and found, mostly by chance and good guessing, that a barrier of paraffin placed between projectile neutrons and target nucleii would slow the neutrons slightly and make them likely to hit more nuclear targets and produce greater radioactivity. In the course of his experiments Fermi split the uranium atom, though it was not clear to him that he had done so. Indeed, when the physical chemists Ida and Walter Noddack, at the University of Freiburg, suggested that he had, Fermi dismissed their suggestion. Instead, he thought, he had found a new element, one higher on the periodic table than uranium.

The mystery of exactly what Fermi had found was taken on by the German radium expert Otto Hahn and the Austrian physicist Lise Meitner, who had collaborated at the Kaiser Wilhelm Institute (KWI) outside Berlin since its opening in 1912. Hahn was the confident and generous German who had worked with Ernest Rutherford in Montreal before returning to Berlin in 1906 and during the First World War had worked on poison gas. Meitner, the daughter of assimilated (even baptized) Viennese Jews, was as shy as Hahn was gregarious, but a hardworking and imaginative scientist. Along with another colleague, Fritz Strassmann, Hahn and Meitner sought to repeat the Curie and Fermi experiments and comprehend their results. But in March 1938 the Anschluss brought Nazi racial laws to bear on Austrians, now citizens of greater Germany, and Meitner was forced to leave Berlin. That July, playing tourist, she bluffed her way across the border with the Netherlands, went next to Copenhagen as a guest of the Bohrs, then came to rest at a physics institute near Stockholm, as arranged by Niels Bohr.

Hahn and Strassmann carried on with the work at KWI. Skeptical especially of the Joilot and Curie findings—it seemed to them implausible that an alpha or a neutron could drive a particle out of a nucleus—they nevertheless pursued the experiment themselves. By bombarding uranium with neutrons, they produced a result that was, in Robert Jungk’s words, ‘chemically incontrovertible but physically inexplicable’: the process yielded small amounts of the element barium, which weighs slightly more than half as much as uranium. Hahn and Strassmann could hardly believe their data. (Neither, for that matter, had Joliot and Curie, Fermi, the Noddacks, or physicists at the Cavendish, who saw energy bursts off a bombarded uranium nucleus as the probable result of equipment malfunction, believed what their eyes told them.) Hahn sent a tentatively worded paper based on the experiment to the journal Naturwissenschaften. He sent a copy of the paper to Meitner in Stockholm. She brought it with her to an inn in the Swedish town of Kungalv, where she was spending the Christmas holiday with her nephew, the physicist Otto Frisch.

Together, Meitner and Frisch studied their colleagues’ paper and its tremulous conclusions; Frisch skied while Meitner walked briskly beside him. Imagining the nucleus as a drop of liquid, a model suggested by Bohr several years earlier, they decided that the intervention of a neutron projected into a uranium nucleus made the nucleus split into two roughly equal pieces. Each had about half the mass of uranium, hence the surprising production of barium in the Hahn-Strassmann experiment. Along with the large pieces came some neutrons liberated from the target nucleus, and these might then collide with other uranium nucleii, and so on, to create a chain reaction. (This feature of the process they did not immediately understand.) With this splitting came also the release of an enormous quantity of energy. Frisch likened the dividing of the nucleus to the way in which bacteria multiply and so dubbed it ‘nuclear fission’, terminology that appeared in the article Frisch wrote with his aunt for the journal Nature and published in February 1939. When Frisch told Bohr about the revelation a month before the article appeared, Bohr slapped his forehead and groaned, ‘How could we have overlooked that so long?’ He would disclose the news of fission to scientists in Washington two weeks later.37

A quarter century had passed since the publication of The World Set Free, Wells’s prediction of fission, nuclear power, and atomic bombs. Leo Szilard had enjoyed the book but thought it ‘moonshine’; now he thought again. In January 1939, just after reading the Hahn-Strassmann article and having heard about Frisch and Meitner’s forthcoming piece in Nature, he wrote to Lewis Strauss, a wealthy Jewish-American financier with a longstanding affection for physics and a particular determination to produce radium for treating patients with cancer, from which his parents had recently died. Szilard alerted Strauss to the two revolutionary articles. Their conclusions, he wrote, ‘might lead to a large-scale production of energy and radioactive elements, unfortunately also perhaps to atomic bombs’. Thereafter Szilard wrote often to Strauss, whom he viewed, accurately as it turned out, as a potential patron and sufficiently well connected to serve as a conduit between the physics community and the politically powerful.38

There is no indication that Szilard had meanwhile encountered another futuristic novel, this one published in 1933 by Harold Nicolson, the husband of Vita Sackville-West and biographer of Tennyson, Lord Byron, and Algernon Charles Swinburne. Nicolson had joined the diplomatic service in 1909 and was a member of the British delegation at Versailles, edited the newspaper of Oswald Mosley’s New Party until Mosley announced his Fascism, and stood for election to Parliament in 1931 (a loss) and then in 1935 (a victory). His novel, entitled Public Faces, brought together Nicolson’s interests in literature, diplomacy, and politics, and the role of gossip in all three. The book pretends that, in the summer of 1935, a geologist from Nottingham named James Livingstone discovered, on the Persian Gulf island of Abu Saad, a strange new ore that he called ‘Deposit A’. Livingstone speculated that the ore, if in sufficient quantity and refined to its ‘pure state’, would immediately ‘transmute itself’ so violently that it would explode, eradicating everyone and everything ‘within a considerable range’. This ‘atomic bomb’, as scientists in the know had quietly begun to call it, no bigger than a parliamentarian’s inkstand, might be powerful enough to destroy a major city.

The liberal members of Prime Minister Spencer Furnivall’s Cabinet, including the ineffectual foreign secretary Walter Bullinger, are appalled at this news, but there is far worse to come. As it happens, Sir Charles Pantry—Sir Charles Portal?—the secretary of state for air, has taken it upon himself to arrange, with the government of India, the excavation and removal from Abu Saad of most of Deposit A. It took very little—‘some coolie detachments from Bombay and a few tankers’, says Pantry offhandedly—to procure this ore, and to leave almost none of it for anyone else. Deposit A was found to be useful for building rocket planes that were light and fast and strong enough to carry Deposit A-based atomic bombs. And, by the way, the Air Ministry had already built eleven rocket planes, and the first test of an atomic bomb to be delivered by one of the planes was scheduled for the upcoming Sunday at dawn.

Pantry is beyond control, or at least Bullinger and rest of the dithering Furnivall Cabinet cannot stop him. Assuming that the circumference of the bomb’s explosion will not be wider than 30 miles, Air Ministry officials authorize its release into the North Atlantic, apparently at a safe distance from any ship and all land masses. But they have miscalculated its power. The bomb creates a tidal wave and an enormous bank of white steam so hot that it scalds to death an underdressed observation plane pilot who flies too close. The wave sinks the British aircraft carrier Albatross, whence the rocket plane flew, the American cruiser Omaha, and SS Calanares of the United Fruit Company. And it inundates Charleston and Myrtle Beach, South Carolina, killing 80,000 people. In his explanation of the disaster, the Prime Minister admits that ‘the destructive range of this bomb had been seriously underestimated’, indeed, by a factor of two and a half. He expresses regret and offers to compensate the Americans. And he proposes to destroy within six months his country’s entire stock of atomic bombs—as long as all the other powers would promise to eschew aerial and submarine warfare. If not, the British government would have to ‘resort to progressive means of compulsion’.

There existed, of course, the possibility that the other powers would not agree to Britain’s conditions. What then? Lady Campbell, the aristocratic mother of Jane Campbell, who was Parliamentary Secretary at the Foreign Office, was not terribly worried, and espoused an early version of nuclear monopoly deterrence that would become popular in Washington in a very few years:

‘War?’ said Lady Campbell, having resumed her knitting. ‘War with whom?’ ‘War with everybody,’ said Jane, swallowing her coffee in desperation.

‘But surely, my dear Jane, how ridiculous you are! If the bomb is as bad as all that, and if we have several of them, no one will dare to go to war. Not if we have enough of those bombs. Besides, in any case, darling, you can’t dash off like this directly after luncheon.’39

Science is experimentation, observation, the careful use of instruments and numbers and applied principles and techniques. It is also imagination, the ability to think beyond received wisdom and to see what the instruments offer the eyes despite what the brain stubbornly insists cannot be true. Not only British scientists, nor those from other places who were welcomed into British laboratories, were capable of imagination, as the work of Joliot and Curie, Fermi, Hahn, Strassmann, Meitner, and Frisch indicates. But it took H. G. Wells and Harold Nicolson to imagine the atomic bomb, and the revelation of Leo Szilard, the Hungarian soaking in his London bathtub, to grasp that the discovery of fission might lead to terrible weapons. Two others transplanted to Britain, Frisch and Rudolf Peierls, would in 1940 crystallize this understanding in a memo of extraordinary consequence. In the end, as Margaret Gowing has written, ‘Britain had been the midwife of this bomb.’40

If you find an error please notify us in the comments. Thank you!