The First War of Physics (62 page)

But, just as the Met Lab physicists had discovered four years previously, the extrapolation from small-scale models tended to overestimate the quantity of uranium required. As layer 61 was put in place on 24 December, it became obvious that one further layer would be sufficient to tip the reactor over the threshold of criticality.

At 2:00pm on 25 December, the three cadmium control rods were inserted and layer 62 was added. Kurchatov arrived to supervise the next step as the building was cleared of all non-essential personnel. Those who remained were silent. Only the clicking of the neutron counters could be heard. There followed a series of experiments in which the control rods were partially withdrawn and the neutron counters monitored to confirm that everything was behaving as expected.

At 6:00pm, F-l went critical. ‘Well, we have reached it’, Kurchatov observed. It was the Soviet programme’s first major success. The physicists congratulated each other, as Kurchatov declared: ‘Atomic energy has now been subordinated to the will of Soviet man.’

Beria arrived to inspect F-1 a few days later. The physicists went through their routines once more and declared that the reactor was operational. But, apart from the noise of the neutron counters, there was nothing to hear and there was certainly nothing to see. Beria was immediately suspicious. ‘Is that all?’, he said. ‘Nothing more?’ He asked if he could go into the reactor room and take a closer look. When Kurchatov insisted it would be too dangerous, Beria grew even more suspicious.

Stalin received a report on the success of F-l on 28 December 1946:

In the first days of work of the uranium-graphite pile (December 25–26–27), we have already obtained the first nuclear chain reaction to be launched in the USSR on a semi-industrial scale. It is now possible to regulate the functioning of the pile in the necessary range and to control the run of the nuclear chain reaction.

Stalin received members of the Special Committee and the scientists who had taken part in the successful F-l project at a formal session at the Kremlin on 9 January 1947. It was the first, and last, time that Stalin agreed to receive reports directly from his atomic scientists.

Book-breaker

The Japanese surrender and the ending of hostilities meant that teams of Army Security Agency (ASA)
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cryptanalysts assigned to work on German and Japanese codes were freed to work on the Soviet message traffic. The breakthroughs secured by Hallock and Phillips at Arlington Hall had now rendered the Soviet messages vulnerable. It had become possible partly to strip away the one-time pad cipher to reveal the underlying, ‘plain’ code groups contained in hundreds of messages that had gone back and forth between Moscow and Soviet embassies, consulates and trade organisations in America.

As the ranks of cryptanalysts swelled to between 50 and 75, that vulnerability increased. One particularly gifted cryptanalyst, Samuel Chew, made use of the highly predictable patterns in messages detailing scheduled shipments of Lend-Lease aid from American ports.

There remained the problem of breaking the code itself. This could only be done either by acquiring a copy of the code book or recreating it from a painstaking analysis of the plain code groups that had now been revealed.

In early 1946 Meredith Gardner joined the Russian project. Gardner was an accomplished linguist who had taught languages at universities in Texas and Wisconsin before the war. He was able to read German, Spanish, French, Sanskrit and Lithuanian and had studied Old High German, Middle High German and Old Church Slavonic. He had astonished his Arlington Hall colleagues by learning Japanese in three months. He now proceeded to learn Russian.

Gardner was the ‘book-breaker’. His task was to use his language skills, identify patterns in the code groups and so, step by step, recreate the code book that the Soviet cipher clerks had used before enciphering their messages using one-time pads. This was a task that called for infinite patience and a certain type of personality. Gardner fitted the bill: ‘tall, gangling, reserved, obviously intelligent, and extremely reluctant to discuss much about his work’, was how FBI counter-intelligence agent Robert Lamphere described him.

The materials provided by Gouzenko were presumably not of direct assistance to Gardner, but he did have some clues in the form of obsolete codebooks. A partially burned codebook had been recovered from a battlefield in Finland, and Donovan had purchased a copy from the Finns for the OSS. This had been passed to the ASA. Such material served as a basis for imagining how newer codebooks might be structured.

In the summer of 1946, Gardner finally began to read portions of some of the messages dated two years previously. He saw enough to convince him that some of these messages related to Soviet espionage.

Some of the messages inevitably referred to English-language names or places, and the Soviet cipher clerks had used a ‘spell table’ to code letters from the Latin alphabet. Gardner managed to reconstruct this spell table and on 20 December he broke into a message from New York to Moscow dated 2 December 1944. He read a list of names:

Hans BETHE, Niels BOHR, Enrico FERMI, John NEWMAN, Bruno ROSSI, George KISTIAKOWSKY, Emilio SEGRE, G.I. TAYLOR, William PENNEY, Arthur COMPTON, Ernest LAWRENCE, Harold UREY, Hans STANARM, Edward TELLER, Percy BRIDGEMAN, Werner EISENBERG, STRASSMAN.

It was a list of Manhattan Project scientists, to which Heisenberg (‘Eisenberg’) and Fritz Strassman’s names had for some reason been appended. Although Gardner did not know it yet, it was the list taken from the report that Hall had passed to Kurnakov and Yatskov in October 1944.

Gouzenko’s defection had unmasked Nunn May, exposing Soviet espionage against the Manhattan Project from the distant Montreal laboratory. Here, it seemed, was evidence of atomic espionage from within America itself.

I hope your baby will be born soon

Fuchs may have rationalised his decision to return to Britain on the basis of some curious sense of loyalty, but the Britain he returned to at the end of June 1946 was bleak and inhospitable. The Attlee government decided to put bread on ration in July, provoking anger from the opposition Conservatives and protests from the Master Bakers’ Federation and the British Housewives’ League. Bread had never been rationed during the war, and the decision to ration it now was taken as a sign of national impoverishment.
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To make matters worse, the UK winter of 1946–47 was one of the most severe on record, with heavy snow falls and temperatures falling to minus 20° Celsius.

Despite these hardships, Fuchs settled into a reasonably comfortable existence at Harwell. There was a small nucleus of Los Alamos physicists at the British research establishment, and a sense of community not unlike that which had developed on the Hill. The scientists also shared a sense of idealism about the possibilities for the peaceful uses of atomic power. Fuchs made some new friends. Cockcroft decorated the site with lawns and flower beds.

Fuchs suspended his espionage activities. At their last meeting he had given Gold instructions for his Soviet contact back in Britain, but he chose not to follow up on those instructions and let the contact lapse. Perhaps he was still somewhat unnerved by the revelations of the Nunn May trial or perhaps he suspected that he was under surveillance. In fact, several expatriate scientists working on sensitive projects were put under surveillance by British intelligence for a time. Fuchs got on with his job in his typically dry, reserved way.

When Peierls and his wife decided to escape the vicissitudes of the severe British winter and take a skiing holiday in Switzerland, Fuchs gratefully accepted an invitation to join them. When he returned to Britain two weeks later, he had resolved to continue to spy for the Soviet Union.

As his contact with Soviet agents was now broken, he thought to re-establish communication through Jurgen Kuczynski, but Kuczynski was now back in Germany, working in the Russian zone of occupation. Another German Communist émigré, Johanna Klopstech, put him in touch with Soviet intelligence. Klopstech was not an agent, but was deemed a ‘reliable person’ by Russian intelligence. Fuchs was instructed to meet his new contact at the Nag’s Head pub in Wood Green, north London, on 27 September 1947. He was to carry with him a copy of
Tribune
magazine, and look for a man carrying a red book.

The man was Alexander Feklisov, the NKVD agent who had managed the Rosenberg network and who had worked alongside Yatskov in New York. Feklisov watched from across the street as Fuchs entered the pub and then followed him inside. Feklisov was able to identify Fuchs from a photograph, but Fuchs did not know what his contact looked like. However, Fuchs spotted the red book and walked up to a panel carrying framed photographs of famous British boxers.

‘I think the best British heavyweight of all time is Bruce Woodcock’, Fuchs declared.

‘Oh no, Tommy Farr is certainly the best’, Feklisov responded.

With these code phrases correctly exchanged, they left the pub separately. Once outside, Feklisov caught up with Fuchs, introduced himself as ‘Eugene’ and gave him a series of questions that he had been asked to put by Moscow Centre, including one concerning the possibility of building the hydrogen bomb, or Super. Fuchs promised to have the answers ready for their next meeting.

Feklisov set the protocols for future meetings, at the Spotted Horse pub in Putney High Street and outside Kew Gardens tube station. They were to meet once every two or three months.

‘I’m very happy to be with you again’, Fuchs said, towards the end of their meeting. ‘I hope your baby is born soon!’

Feklisov didn’t understand. ‘Which baby?’ he asked.

‘Your bomb. From the questions you’re asking me I estimate it will take you one to two years. The Americans and our own research scientists think it’ll take you seven or eight years. They’re very wrong and I’m delighted.’

Fuchs then handed over a bulky package containing important information on the production of plutonium which he had acquired after he had returned to Britain.

‘Thank you’, Feklisov said simply.

‘My pleasure’, said Fuchs. ‘I shall always be indebted to you.’

Fuchs advised Feklisov of the British decision to embark on an independent bomb programme. Britain’s first atomic weapon was to be a plutonium bomb, and William Penney had been appointed to head weapons development at the Ministry of Defence’s Fort Halstead site in Kent. At the time, not even Fuchs’ Harwell colleagues were aware of this decision.

When the Combined Policy Committee convened a three-day meeting in Washington in November 1947 to determine what kind of atomic information could be declassified, it was Fuchs who represented British interests. He sat in the meeting alongside the British co-secretary, Donald Maclean, presumably neither knowing that the other was a Soviet spy. One participant later recalled a certain sense of exasperation with Fuchs’ rather conservative assessment of which information could be safely declassified, and which should remain secret.

Life in Sarov

Soviet physicists began to arrive in numbers at Arzamas-16 in the spring of 1947. Veniamin Tsukerman, an expert in the flash radiography of explosions, recruited to the project by Khariton, described his arrival in May:

We had arrived in what was for us a new world. Everything was unexpected: the thick forest, the beautiful, centuries-old pines, the monastery on the high river bank with its cathedrals and white bell tower. And,
in sharp contrast, the grey columns of prisoners who went through the village in the morning and in the evening.

The Autonomous Republic of Mordovia was a region of prison camps. Because of the sensitive nature of the installation being built in Sarov, no political prisoners were used. The prisoners who constructed it were
ukazniki
, people found guilty of infringing the many decrees (called
ukazy)
which applied outside the normal criminal code. For those prisoners whose sentences unhelpfully ended during the construction phase, Beria’s solution was simple. He extended their sentences. After their release, they were sent to the far eastern corner of the Soviet Union, as far away as possible from the facility they had helped to build. The ‘grey columns of prisoners’ were rarely mentioned by the scientists now assembling at Arzamas-16 but, as Khariton observed, they regularly intruded on the scientists’ consciousness.

Although the scientists were notionally free, in truth they too were cosseted prisoners. The Soviet atomic industry was being developed as a network of highly secret facilities within a ‘Closed Administrative and Territorial Formation’ (known by its Russian initials as a ZATO). It was eventually to become known as the ‘White Archipelago’. Conditions were at least better than those prevailing in the prison camps that formed the notorious ‘Gulag Archipelago’. The American and émigré scientists and their families that had gathered on the Hill in 1943 complained bitterly about the ‘concentration camp’ conditions behind the razor-wire-topped fences. But at Arzamas-16 the oppressive conditions were greatly amplified by the thinly-veiled threat of extreme punishment in the event of failure. This was, after all, a project led by Stalin’s most feared executioner.

Physicist Lev Altshuler described the effect this had on him:

It was not merely a regime, it was a way of life, which defined people’s behaviour, thoughts and spiritual condition. I often dreamt the same dream, from which I would awaken in a cold sweat. I dreamt that I was in Moscow, walking down the street carrying top secret and extremely
top secret documents in my briefcase. I was killed because I could not explain why I had them.

But it is a characteristic of the specifically Russian human condition under Stalin that amid the oppressive secrecy and fear there was also great enthusiasm, art, romance and humour. The immense suffering that the country had endured in the war was a raw collective memory. The scientists perceived the threat of an American attack using atomic weapons as very real, and now worked hard to restore the balance of atomic power. As Tsukerman observed: