James Robertson readied an elaborate system of code names—Fuchs was Ramsey, Peierls was Matthews, and Skinner was Piper (and of course his wife became Mrs. Piper). He had the warrants to tap the phones of Fuchs and Peierls and monitor their mail. He made a request for bank records and three Listeners, young female volunteers from the MI5 transcription team, to work from a side room at the Victorian-era post office in the backwater town of Newbury, near Harwell. All day, all night, they staffed the phone taps and microphones while equipment recorded Fuchs’s every word, whether in the office or at home. Just in case, one of them spoke German. When the Listeners were relieved, they had an easy ten-minute walk through the old market square and over the river Kennet to their eighteenth-century coach inn. Their cover story, should anyone ask, was as General Post Office relief staff working on a statistical study of calls passing through the Newbury exchange.
As for mail, the Special Investigative Unit of the GPO, located near St. Paul’s in London, opened Fuchs’s incoming and outgoing mail, mostly using a steam kettle, and copied it. Checking for invisible ink was also part of the job.
The listening and the mail duplication flowed easily for Robertson, but he wrung his hands over visual surveillance. Because the treeless acres of Harwell offered no cover, a select team of Watchers was on call a few hours away, in a Georgian town house in Regent’s Park on the northwest side of London. The chief of the Watchers, Jim Skardon, was described by a colleague as dapper and pipe smoking. His other important qualities were patience and tenacity. He had “a high opinion of his own abilities,” said one, but was well liked and an excellent interviewer. Their physical separation from Leconfield House supposedly thwarted foreign agents’ observation of comings and goings of this MI5 surveillance team.
The Watchers had a photograph of their target and a basic description—Height: five feet nine, Eyes: brown, Hair: brown. From Arnold they knew that during the week, Fuchs’s pattern was office, home, or the Skinners’. Occasionally, he made train trips to London for meetings at Shell Mex House or drives to Birmingham to see the Peierlses. When he traveled by rail, the Watchers waited for him at Didcot Station, the closest one to Harwell. If he drove, Robertson had Watchers pick up his car on a trunk road a few miles into his trip. Lightly trafficked rural roads reasoned against tailing him from Harwell. Information from Arnold or the Listeners kept tabs on his plans. If the Watchers couldn’t get to Harwell in time, the backup was to intercept him either at the train station or at his destination.
When he went out on a whim, especially at night, nothing could be done, which was the cause of Robertson’s anxiety. With holes, the whole system was worthless. But even if they were on the scene, would they be able to detect a handoff that might take less than a minute and involve a servant, a casual acquaintance, or limitless other possibilities? Besides, they knew they could be spying on someone who was not a spy but merely going on about his business.
The first days of tracking had their tribulations, especially Sundays, a free day with no fixed schedule. The first Sunday, garbled messages sprinkled with the voices of strange men forced Robertson to drive to Newbury to learn details firsthand. It all turned out innocently enough. It seems that car trouble outside Harwell had triggered phone calls from Fuchs, a stay at the Skinners’, and—according to a neighbor—unidentified men stopping at the Skinners’ in the middle of the night. The muddle involved Fuchs’s recent purchase of a car from Herbert Skinner: a used dark gray sedan, which looked like new, its long hood and tall gleaming grille with the prominent MG crest now signaling Fuchs’s arrival—when it didn’t break down.
Fuchs invited Arnold to drive it sometime. Pleased, Arnold reported to MI5 that he could keep an eye on the mileage, which shouldn’t increase much because wartime gas rationing was still in effect. Nevertheless, the next Sunday, MI5 lost Fuchs from 1:00 in the afternoon until 4:00 the next morning; the Listeners heard no sounds from his house. Arnold guessed that he was at the Skinners’.
The first real test of a road trip came on Thursday, September 22, when Fuchs and Skinner drove to the General Electric Company in Wembley, on the western outskirts of London. The prior day’s activities, all recorded by the Listeners, involved their secretaries going to and fro about who would drive and in how many cars, given that two others were coming along. Robertson recapped the trip’s arrangements as “working satisfactorily enough.” The only person disappointed was Erna Skinner, who wasn’t allowed to go along.
The investigation slogged along, discovering mostly that Fuchs had a very mundane life and spent most of his time working. The Listeners noted that on weekdays he usually got up around 8:30. Sometimes he whistled. At the other end of the day, it was mostly quiet after 11:30 p.m.—perhaps broken by a sneeze. Weekends were much looser—later rising and later retiring.
Meetings, memos, and list-making clogged the routines of Martin and Robertson. They kept up Fuchs’s multiple security files, now exploding with details on every person he spoke with on the phone, corresponded with, or saw face to face. Identifying first names mentioned on the bugs was a tiresome chore. Robertson kept updating his list of code names. The town of Cambridge became “Backwood”—indicating that perhaps the labeler was from Oxford; Maidenhead easily converted to “Virginia”; and Beaconsfield was designated “Primrose,” a historical nod to the favorite flower of Benjamin Disraeli, a.k.a. Lord Beaconsfield.
One September morning around 9:40, the Listeners reported two visitors (and maybe a baby) who were not the Skinners. The wife, who had a foreign accent, did most of the talking and was “difficult to follow as her speech was a mixture of shouting and screaming. She addressed RAMSEY by his first name.” At 9:46, they probably left the living room, the Listeners noted, to tour the prefab. Not clear who they were (although it was probably the Peierlses).
The prefabs, compact aluminum boxes with two bedrooms, a bath, and a kitchen with built-in fridge, were a marvel to all. They had evolved as a postwar solution to a lack of housing. As though pressed from a cookie cutter, these efficient boxes stretched row upon row across Harwell’s gentle hills.
Fuchs’s regular visitor was Erna Skinner. The friendship between the Skinners and Fuchs had sprung up in 1947—and particularly between Erna and Klaus. Erna most likely forged the relationship because typically, wherever he lived, the wives of his scientist friends mothered him. His quiet nature with the agreeable but evasive smile appealed to their expressive personalities and challenged the maternal instincts of the likes of Genia Peierls, Mici Teller, and Mary Buneman. The women at Harwell had him over for dinner, hung his drapes, sometimes even came over to cook breakfast for him. Klaus was generally friendly toward people, expressing neither his likes nor his dislikes, and didn’t welcome any hint of emotional interest, except from Erna Skinner.
By 1949, he and Erna saw each other almost daily, either for lunch or in the evening, sometimes at his prefab, sometimes at her house. Erna’s background and personality made her a natural complement to Klaus’s reserve. She was fun-loving, outgoing, very bohemian with many artistic, cosmopolitan friends—the patina of her heritage—and a big drinker. She had been pretty and, although she had gained weight, still “had pretty remains,” as Mary Buneman put it. Erna’s specialty was acting out hilarious stories of her everyday happenings and poking fun at herself. And sometimes others. She labeled Klaus’s discourses “evangelistic sermons on democratic principles.”
Being four years his senior might have added to the attraction too. He seemed to prefer older women.
For Erna, an anxious person who required constant companionship, he was a godsend. Caring for him during the summer, while she nursed him back to health from his lung condition, was hardly an imposition. With the impending move, Herbert traveled to Liverpool every few weeks, and she didn’t want to be alone.
Henry Arnold described Erna: “Age about 37. Plump. Short (5’4” to 5’5”). Dark. Attractive type of Jewess. Generally well-dressed though inclined to be untidy. Clothes usually darkish.” In the Yiddish of her hometown of Czernowitz, she would have been “zaftig”—round and full figured. Listeners’ reports indicated that she talked a lot—about trivial incidents that no one seemed to listen to, about her health, and about her kittens. Mary Buneman liked her but thought her a flirt.
Erna Skinner, née Wurmbrand, was nominally Austrian, born in the city of Czernowitz in 1907, a slice of central Europe that was part of the Austro-Hungarian Empire then. Originally a city in Moldova, centuries of submission to Romanian, Ukrainian, Russian, German, and Polish conquerors and the accompanying waves of immigration seasoned it into a multicultural, multiethnic, and prominent intellectual center. It had a slight plurality of Jews, and German was the lingua franca. Erna was a product of this rich culture, and her casual patter, often seemingly frivolous, concealed a lively intelligence and quick mind.
The sterile details from British passport records requested by Robertson listed that Erna divorced a husband named Abrahamson before coming to the U.K. in 1929, visited Boston in 1932 for six months, and traveled extensively on the Continent before the war. She lived in the United States in 1944 while Herbert worked for the Manhattan Project in Berkeley, California. Her parents lived in New York. Not on the passport records—her father was a respected journalist who reported on atrocities in Germany until 1933, when Nazi intimidation forced him out.
The Skinners had married in 1931 and in 1934 had a daughter named Elaine. During this time, Herbert Skinner was on the faculty of the University of Bristol, and Klaus was a student there. Herbert later recalled Klaus as “an uncouth and callow youth.” There is no indication that they knew each other well.
Mary Buneman found Herbert Wakefield Banks Skinner a proper English gentleman, reserved, and discreet, as one might expect of a graduate of the elite prep school Rugby and of Trinity College, Cambridge—and now, besides being Klaus’s boss, was deputy to the director of Harwell, John Cockcroft. He also had an aptitude for the clerihew, a distinctly British form of poetry, whimsical and often nonsensical, as was his for Fuchs:
Fuchs
Looks
An ascetic
Theoretic.
Herbert and Erna were devoted to each other in their own way. He wanted to keep her happy. But for Erna, one man was not always enough. He knew of her affairs and looked the other way. Klaus, for his part, satisfied her whims and needs and let her take the lead. At the same time, he held an admiration for Herbert and a willingness to please him and do what he asked. Mary Buneman once asked him why he went over to the Skinners’ all the time. He answered, “For Herbert.” But it seemed more complicated than that.
Arnold considered Erna to be Fuchs’s mistress, although Robertson didn’t have that impression at first and noted for the record that no evidence existed. He later agreed with Arnold. Herbert evidenced no suspicions about the relationship—except on one particular day, when Fuchs and Skinner had a meeting at Shell Mex House and the relationship between the two men was very cool. The Watchers reported that they arrived at the Didcot Station separately, rode in the first-class car but sat apart, took the same tube car, but didn’t speak or sit together. They traveled back to Harwell separately. It was a complete break from their usual routine.
The fracture, whatever its cause, didn’t last. The next day Fuchs visited the Skinners for a few minutes, and then they visited him at the prefab along with Herbert’s aunt Bess, problem seemingly resolved. The phone bugs offered no explanation.
Other facets of Erna’s life Robertson did question. Very shortly he would learn that she had a distinctly peculiar set of friends. By month’s end, MI5 had a tap on the Skinners’ phone.
Fuchs wasn’t the only prime suspect MI5 was following. Rudi Peierls was the other. Robertson already had mail and phone checks on Peierls, but other than maligning his sartorial display (“shabby raincoat with belt, dark grey soft hat with black band—brim turned up all round,” and so on), the Watchers didn’t report much. Then, on September 19, Martin wrote to Washington with an explosive finding. Peierls had a sister in the United States. This fact came from a 1938 letter supporting U.K. visas for his parents, who were traveling from Berlin to America. Having a sister in the United States was a key factor that came out of Venona. Now Fuchs wasn’t the only candidate for “Rest.”
The FBI and the British embassy in Washington responded quickly, saying that the time frame in the Venona messages didn’t match Peierls’s movements. Namely, he took up a position in Los Alamos on July 1, 1944. The government was unlikely to consider transferring him back to the U.K. that same month. MI5’s director general, however, didn’t want the timetable embedded in the Venona messages, which might not fit exactly with the actual events, to dictate the possibilities. Most, though, still held Fuchs to be the guilty one.
The presence of a sister was an essential factor. The exact details on Peierls were lacking as yet, but evidence on Kristel Fuchs Heinemann and her husband, Bob, crisscrossed between the embassy in Washington and MI5. London uncovered that in June 1937, Bob, then a student at Swarthmore, had visited the U.K. en route to Leningrad. And in 1944, the FBI learned that he had been a member of the Communist Party in Cambridge, Massachusetts, resigned, and rejoined in 1947 using the alias Robert Hill. Robertson requested any records on Kristel held by the Home Office, and a few days later he applied for a warrant to open mail from her. His minute on September 20 read,
The address of FUCHS’ sister, Mrs. Kristel F. Heineman [sic], has now been obtained from the F.B.I. and is 96 Lake View Avenue, Cambridge, Massachusetts U.S.A.
In view of the information in our records regarding this woman’s possible past implication in Russian espionage, and especially the fact that her name was found in a diary of the spy Israel Halperin, I should be grateful if you would approve the operation of a H.O.W. [a warrant] on all correspondence addressed to her from this country.
It wasn’t long before Robertson requested that her letters be checked for secret ink.
As the minute indicated, a week or so earlier a cable from Washington had spelled out another troubling fact about Kristel: her name was listed in the diary of Israel Halperin, the mathematician arrested for spying by the Canadians after Igor Gouzenko, a clerk at the Russian embassy in Ottawa who defected in 1945, had implicated him. In 1947, the courts acquitted Halperin, and he resumed his faculty position at Queen’s University in Ontario. MI5’s director general, Percy Sillitoe, wanted the FBI to investigate his movements between 1942 and 1945. He didn’t think Halperin could be the elusive “Goose,” the Russians’ code name for Rest’s courier in New York, but he wanted to make sure.
Similarly, Martin pressured his main contact at the embassy in Washington, Geoffrey Patterson, to find Kristel’s whereabouts in 1944. Patterson pushed the FBI agents, and they pushed back. They had already worked for a week and found nothing. It was “extremely difficult,” Martin heard, to trace the movements of a U.S. national during 1944. So he abbreviated his request. Could they at least confirm that she was somewhere in the United States during that time? Was her husband connected with Harvard at the present time, and might Harvard have some information? Urgency pulsed through the request. Until the FBI sorted out the sisters of Fuchs and Peierls, MI5 couldn’t eliminate either man as a suspect. They had to cover them both around the clock, and the agency was stretched.
On September 23, 1949, Harry Truman made a public announcement that confirmed the suspicions of Western intelligence and otherwise stunned the world: Russia had exploded an atomic bomb. The next day, eager to watch Fuchs’s reaction to the news, Arnold knocked on his door. It was around 11:00 on Saturday morning, and Fuchs was just stirring. Arnold started in right away saying that he had come around because of the news. He feigned confusion. “I don’t know what to make of this. Do you?” Fuchs simply replied, “Well we don’t—I mean, we want to know the details.” After a cigarette and twenty-five minutes of Arnold’s mostly one-sided conversation, he departed.