Before the Fallout Page 13
However, in 1934, Kapitza made an ill-advised visit to Russia. Just as he was preparing to return to Cambridge, he was informed that the Soviet Union "could no longer dispense with his services, in view of the danger from Hitler." His second wife, Anna, whom he had married in 1927, was allowed to return with the news to England, from where she sent her frustrated husband parcels of everything from toilet paper to trousers, both of which he discovered were, unlike oysters and smoked sturgeon, virtually unobtainable in Russia.
Rutherford was shocked and angry. He tried everything he could to pressure the Soviet government, but to no avail. In the end, all he could do was to offer to ship Kapitza the brand-new equipment installed for him in the Mond Laboratory, which reached Leningrad jumbled up in a cargo of frozen meat. After much argument, the Russian government paid thirty thousand pounds for the apparatus and installed it in a lavish new institute, built expressly for Kapitza. By 1936 the trapped Russian, for whom there would be no more dinners at high table in Cambridge or thoughts of a peerage, reflected philosophically to Rutherford that "we are only small particles of floating matter in a stream which we call fate. . . . the stream governs us. . . ." Rutherford wrote bracingly but sympathetically, "A reasonable number of fleas is good for a dog—but I expect you feel you have more than the average number."
Peter Kapitza s crocodile on the Mond Laboratory at Cambridge
Anna Kapitza, who rejoined her husband in Moscow in 193c, believed that Rutherford's staunch support had kept her highly strung husband from suicide, confiding, "I am absolutely certain I owe to you the life of Kapitza, without his love and gratitude to you, without your invaluable help . . . he would not be alive."*
Kapitza would survive the savage purges that would reach their peak in 1937—38 when nearly 8 million were arrested, including one hundred physicists (many of whom were shot or vanished into the gulags). Abram Joffe would also be spared to sustain Soviet physics through these precarious times. However, fear of the nighttime knock on the door sapped the creativity of Russian scientists at a critical time for nuclear physics.
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Kapitza's was not the only departure from the Cavendish. James Chadwick, highly impressed by the performance and potential of Lawrence's cyclotron, was growing restive. As he later wrote, "It was becoming very difficult to push on without some new equipment. . . . we needed a means of accelerating protons or other particles . . . at high energies. But that meant more space, particularly more money, and particularly engineering. It meant complicated equipment, and Rutherford had a horror of complicated equipment."
And Rutherford would not budge. Lacking Kapitza's shameless ability to charm and manipulate Rutherford, and anxious not to quarrel with his mentor of some quarter of a century, Chadwick thought it best to leave. In 1935, while Rutherford was embroiled in his campaign to persuade the Soviets to release Kapitza, Chadwick was offered the chair of physics at Liverpool University and accepted. Rutherford backed him, telling Liverpool they would be fortunate if they could attract Chadwick. He also backed Chadwick for the Nobel Prize for Physics, which Chadwick was awarded that year for his discovery of the neutron. It may have been nervousness that made him drop the check handed to him by King Gustav at the presentation ceremony in Stockholm. He remained a quiet, shy man who did not enjoy public occasions, which often prompted a flare-up of his digestive problems. After hearing Frederic Joliot-Curie deliver his Nobel lecture in Stockholm at the same presentation, Chadwick wrote, perhaps a little enviously, that "he was a great actor. He liked that kind of thing, and he did it very well."
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In 1937, while Chadwick was struggling to modernize Liverpool University's primitive physics department, experimental atomic physics unexpectedly lost its linchpin. Unlike Marie Curie, Rutherford's health had not apparently suffered from his cavalier approach to radioactive materials. (On a lecture tour in the United States he once happily discarded a paper he had used to funnel uranium salts into a tube. The paper was retrieved by his hosts, who used it as a radioactive source for forty years.) However, for some years Rutherford had been suffering from a small umbilical hernia. On 14 October he began feeling sharp stomach pains and started vomiting. His doctor operated for a routine strangulated hernia, but Rutherford suddenly worsened. On 19 October Lady Rutherford wrote in despair to Chadwick that her husband was "only hanging by a thread." He died that evening at the age of just sixty-six.
The scientific community was shocked by the unexpected death of a larger-than-life character so full of creative energy, who had roamed his laboratory, dribbling ash from his pipe, and encouraging his researchers with raucous cries of "I feel it in my water." During his career he had trained a dozen Nobel Prize winners. In the words of one researcher, his death left them feeling "stupefied rather than miserable." It simply "did not seem in the nature of things." Rutherford was cremated, and his ashes were buried near the tomb of Sir Isaac Newton in Westminster Abbev. From his exile in the United States Einstein mourned the passing of "one of the greatest experimental scientists of all time." A tearful Niels Bohr, recently returned from a lecture tour around Japan that had included an audience with Emperor Hirohito, remarked that like Galileo, Rutherford left science "in quite a different state from that in which he found it."
Rutherford had remained true to his philosophy that "it was not that the [nuclear] experimenters were searching for a new source of power or the production of rare or costly elements. The real reason lay deeper and was bound up with the urge and fascination of a search into one of the deepest secrets of nature." Yet even he had come privately to suspect that scientists might not have the luxury of the disinterested pursuit of knowledge for much longer. Despite his public comment of "moonshine," he had in the early 1930s alerted Sir Maurice Hankey, secretary of the Committee of Imperial Defence, that the Cavendish Laboratory's nuclear work might one day be crucial to the nation's defense. He advised the government to "keep an eye on the matter."
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At the Institute of Physics in Rome, Enrico Fermi had been following up the Joliot-Curies' discovery of artificial radioactivity when he had an inspired thought. What, he wondered, would happen if he used neutrons instead of alpha particles to bombard elements? He reasoned that neutrons should be even more effective in producing artificial radioactivity since, having no charge, they would be more likely to penetrate the nucleus. He set to work with his small team, which included Emilio Segre. Segre recalled that like "a steamroller that moved slowly but knew no obstacles," Fermi systematically went through the periodic table, irradiating each element with neutrons. The first eight produced nothing, but at the ninth, fluorine, the Geiger counter clicked into life, registering artificially produced radioactivity.
As Fermi progressed through the table, some of the radioactive isotopes he created were so short-lived he had to race down the corridor with them to the Geiger counters before the radioactive emissions ceased as they decayed to stability. In May 1934 he reached the final element, number 92, uranium. He found that bombarding this heaviest of metals appeared to produce one or more new radioactive elements beyond uranium in the periodic table: the so-called transuranics. Fermi published his results in a series of reports. In Copenhagen scientists crowded around Otto Frisch, one of the few able to translate from Italian. The Italian press gleefully hailed Fermi's discoveries as proof that a Fascist Italy under Benito Mussolini had resumed its "ancient role of teacher and vanguard in all fields."
The chemical complexities of the products formed in uranium by neutron bombardment were, for the present, too great for Fermi to intrepret. However, in the process of irradiating elements with neutrons, Fermi made what he regarded as the most important of all his achievements. He discovered that the more slowly neutrons traveled, the more likely they were to penetrate the nucleus of the target. Like many of the great discoveries, it had come about through intuition. Fermi had decided on impulse to see what happened if he filtered the neutrons he was firing at his targe
t through a barrier of paraffin. To his surprise, this increased the level of artificial radioactivity produced by one hundredfold, so that "the counter clicked madly." Suspecting that the large amount of hydrogen in paraffin might be a factor, he experimented with another substance also containing large amounts of hydrogen: water.
Fermi's assistants brought it in buckets from the goldfish fountain in the garden behind the laboratory, and Fermi channeled neutrons though it. The effect was the same as with the paraffin: the level of artificial radioactivity was enormously enhanced. Fermi deduced that the cause must be the protons in the hydrogen filter. They had a similar mass to the neutrons and, colliding with them, made the neutrons bounce elastically back and forth, absorbing some of their momentum. By the time the neutrons moved on to the target, their speed—ordinarily thousands of miles a second—had been sufficiently slowed—"moderated"—for them to slide more easily into the target nuclei. Fermi and his collaborators quickly filed a patent on the slow-neutron process. Unknown to them, the process would prove critical to the development of the atom bomb.
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Across Europe, laboratories began replicating Fermi's bombardment of elements with slow neutrons. Lise Meitner found his idea of transuranics "so fascinating" that she determined to pursue it. Needing the help of "an outstanding chemist," she asked Otto Hahn to resume the direct collaboration they had abandoned some years earlier. Together, they bombarded uranium with neutrons so they could compare their findings with Fermi's and confirmed to their satisfaction that he had indeed created new elements beyond uranium.
They were wrong. Like most scientists of the day, they erroneously believed that all nuclear reactions—even when produced by the neutron—were small. Thus, when a new element was formed, it differed from the original by only a few protons or neutrons. It did not occur to them that they were observing the results of something much more dramatic. Fermi had not created transuranics; he had split the nucleus of uranium, thereby creating lighter elements lower down in the periodic table.
Only one scientist scented what the new discoveries might mean. In September 1934 German chemist Ida Noddack, the codiscoverer of rhenium, the last naturally occurring element to be identified, published an article challenging Fermi's claim to have created transuranics. She suggested it was "conceivable that when heavy nuclei are bombarded by neutrons, the nuclei in question might break up into a number of pieces, which would no doubt be isotopes of known elements but not neighbors of the irradiated elements." In other words, it was perfectly possible for the nucleus of a heavy atom such as uranium to shatter, releasing far more energy than most scientists believed and transmuting into much lighter elements. She was on the brink of revealing nuclear fission.
However, Noddack did not pursue the thought, and nobody else paid any attention. Emilio Segre wrote in later years of his enduring amazement that no one had taken Noddack's article seriously: "It said that fission was observed. Fermi and I read it and we still didn't discover fission. The whole story of our failure is a mystery to me." Ida Noddack was ignored partly because she was a woman. The respect afforded to Marie Curie and Lise Meitner was the exception. Even they had often been marginalized. Long before the Nazis came to power, editors had refused to publish Meitner's papers on the grounds that she was female. In group photographs of workers at her institute she was often placed at the back or to one side, or even omitted altogether.
Of perhaps greater significance, though, was Noddack's lack of credibility. In 1925 Ida Tacke, as she then was known, and her future husband, chemist Walther Noddack, had claimed to have discovered an element, "masurium," but later could not substantiate it. Emilio Segre himself considered them worse than incompetent, believing they had been "plain dishonest." Lise Meitner had been one of their greatest critics and felt no inclination, a decade later, to pay attention to Ida Noddack's work. Otto Hahn was equally dismissive. When Ida Noddack asked him at least to refer in his lectures and papers to her criticisms of Fermi's work, he replied that he did not wish to make her look ridiculous. Her "assumption of the bursting of the uranium nucleus into larger fragments," he said with crushing emphasis, "was really absurd."
*The discovery of the positron was the first clear indication that the universe consisted of antimatter as well as matter.
* According to one story, when Kapitza finally returned to Cambridge thirty years later, in the 1960s, he was invited to dine at Trinity College. To his consternation he realized he had no academic gown to wear. The college butler came to the rescue, producing Kapitza's original gown, unworn since 1934.
SEVEN
"WONDERFUL FINDINGS"
WHILE SCIENTISTS BICKERED and debated, the international situation was worsening. In Spain in 1936, civil war had broken out between the Republican government and General Francisco Franco's rebel junta. The Soviet Union supported the Republicans, and Fascist Germany and Italy backed the junta, sending arms and men and, in particular, "volunteers" from their air forces. On Monday, 26 April 1937, German and Italian bombers, including the new German Heinkel 11 is and Dormier 17s, attacked the historic Basque capital of Guernica for three hours during the weekly market. Guernica had no air defenses, and so the planes flew low, bombing and machine-gunning with impunity. One survivor remembered "a sapphire blue light" as incendiaries exploded. Another, a child, recalled, "You could see the heads of the flyers, see they were German planes. . . . the next day the town was still burning in some places and there were corpses in the street." According to the Basque government, 1,645 people died out of about 10,000, including 3,000 refugees, in the town. The presence of foreign reporters near the town gave the bombing immediate, appalled prominence. Pablo Picasso's painting gave it immortal infamy.
In 1936 the Japanese government signed the Anti-Comintern Pact with Nazi Germany: Italy joined a year later. In so doing Japan allied itself firmly with the rising European dictatorships and against the Western democracies, aiming to create a new order in the East as they did in the West. It was not long in taking further practical steps to achieve this goal. In July 1937 the Japanese turned their encroachment into China, resumed six years earlier in Manchuria, into a full-scale war of conquest.
Many inhabitants of Hiroshima considered this war "a Holy Crusade," and Hiroshima's port was once more filled with warships and transports bound for China. Local residents lined the streets to give a rousing send-off to the departing troops of the Fifth Division, based in the city's castle. Later they bowed their heads in somber respect as returning soldiers paraded down silent streets with white boxes around their necks containing the ashes of fallen comrades. In December 1937 the people of Hiroshima celebrated the capture by Japanese troops of Nanking—the capital of Nationalist China—with a massive lantern parade. They then gathered outside the city hall to listen to a military band. Pictures showed numerous women and children among the crowds.
Strict government censorship kept them from learning that the behavior of the Japanese troops after the fall of Nanking had been barbarous. Ninety thousand Chinese soldiers who had surrendered under promise of fair treatment were killed, many of them bound and used for bayonet practice. A Japanese soldier wrote that among the civilians "women suffered most. . . . we sent out coal trucks to the city streets to seize a lot of women. And then each of them was allocated to 1 £ to 20 soldiers for sexual intercourse and abuse. After raping we would also kill them." Some two hundred thousand of the city's civilian population of around half a million are estimated to have been killed, in addition to the ninety thousand surrendered prisoners. The commander of the victorious Japanese forces announced, "The dawn of the renaissance of the East is appearing."
Both Britain and the United States protested at the rape of Nanking but took no firm action; nor did they do so after the Japanese bombed Shanghai in September 1937. However, the U.S. government condemned such bombing in the following words: "The American Government holds the viewr that any general bombing of an extensive area, where there resides a
large population engaged in peaceable pursuits is unwarranted and contrary to principles of law and humanity."
That summer, Emperor Hirohito authorized "special chemical warfare units" to be sent to the Asian mainland. The Japanese were to use poison gas against the Chinese on many occasions. They also used bacteriological weapons, releasing rats infected with the plague and other toxins. When rats were released in the wrong place, sixteen hundred Japanese troops became infected and died.
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At the Curie Laboratory, Irene Joliot-Curie was driving herself and her team unsparingly. After her husband, Frederic, was appointed professor at the College de France in Paris, where he built a laboratory dedicated to nuclear physics and began work on a thirty-two-inch cyclotron, she worked closely with a Yugoslav colleague, Pavel Savitch. In late 1937 they announced that, by bombarding uranium with neutrons, they had found a substance that remained radioactive for more than three hours. Over the coming months they published a series of explanations of what this highly active material might be: First they suggested thorium, then actinium, then a transuranic with the chemical properties of lanthanum. Otto Hahn and Lise Meitner, deep in their own investigation of transuranics and skeptical of both the Paris team's techniques and their findings, dubbed it "curiosium." Lise Meitner thought that Irene Joliot-Curie was "still relying on the chemical knowledge she received from her famous mother and that knowledge is just a bit out of date today." Hahn remarked less delicately of some of Irene Joliot-Curie's results, "This damned woman. Now I will have to waste six months proving that she was wrong."