The Secret Lives of Codebreakers

by Sinclair McKay

  In other words, the portrait we appear to be presented with is one of a classic borderline-Asperger’s quirky scientist. His eccentricities have been well rehearsed: among them was his bicycle, with a chain that was poised to fall off after so many rotations, which meant that Turing had to calculate exactly the moment at which to start moving the pedals backward to avert this. And he had the habit of cycling around the countryside while wearing a full gas mask.

  Yet perhaps there was a logical advantage in having a bicycle that no one else would know how to use without the thing falling to bits? And the simple fact was that Turing suffered badly from hay fever. The gas mask was a practical, if drastic, solution to the difficulty.

  Moreover, unlike the usual shambling professor, Turing was remarkably physically fit. Though he had no time for organized field games, he was extremely keen on running, and took part in a great many races. Around the time he joined Bletchley Park, he had built up sufficient endurance to run marathons. It has been suggested that he channeled a great deal of sexual frustration into these distance runs; but the real satisfaction may have derived from a sport in which he had complete control, and which relied as much on concentration and mental focus as it did on physical power.

  As Sarah Baring recalls: “We just knew him as ‘the Prof.’ He seemed terribly shy.” Certainly, while at Bletchley, Turing was not greatly interested in social interaction. Yet he was a more radical, open, honest soul than the accounts suggest.

  Turing became a Fellow of King’s College. In the late 1930s, he headed to the United States, to Princeton. Building bridges between the two disciplines of mathematics and applied physics, he threw himself into the construction of a “Turing machine,” a machine that could carry out logical binary calculations. Having seen a tide-predicting machine some years back in Liverpool, it occurred to him that the principle of this device could be applied to his own machine, greatly speeding its function.

  By 1938, when it was increasingly clear that war was coming to the whole of Europe, Turing returned to England, and to King’s, with his electric multiplier machine mounted on a breadboard. It was now that he decided to share his talent with the Government Code and Cypher School in the Broadway Buildings.

  There he was given training sessions in the basics of code work and intelligence gathering. After one of these sessions, at Christmas 1938, he found himself working alongside Dilly Knox. Nine months before Britain went to war with Germany, Alistair Denniston had wisely started to speed up the process of cracking the problem of Enigma. At the beginning of 1939, Turing returned to Cambridge, now apprised of the intense secrecy of the matter, and began to apply himself to the intellectual challenge.

  Throughout 1939, Turing and Gordon Welchman attended “short courses” in cryptography organized by GC&CS. Their names are to be seen on contemporary memos, in pencil, with ticks beside them, as though they were part of a school register.

  But it was not just mathematicians that were needed. Other disciplines lent themselves to the work of codebreaking equally well. One could be a historian or a classicist. Famously, one could be an expert at solving the Daily Telegraph cryptic crossword in less than twelve minutes. One could also be a chess expert or grand master—as indeed were young Bletchley recruit Hugh Alexander and a number of the young recruits that he in turn bought along. “Of course, we were also very good at Scrabble and anagrams,” says one veteran.

  Secret service officer Captain Frederick Winterbotham, author of the pioneering book on Ultra, noted that many of the young people coming in had strong musical predilections; an inclination also recalled by Gordon Welchman, who summoned the rather beautiful image of youthful codebreakers “singing madrigals on a summer’s evening” by the waters of the Grand Union Canal.

  But very quickly, Alistair Denniston detected that the gentle setting itself, the house and its spacious grounds, might be regarded as a nuisance by those who worked there, many of whom were coming from London. In a letter from September 1939, to Sir Stewart Menzies, the deputy (soon-to-be) head of the Secret Intelligence Service, Denniston wrote:

  The Government Code and Cypher School was moved out of London by the orders of the Admiral and not by order of the Foreign Office…the work [requires] a high degree of concentration in over-crowded rooms…billeting has forced the staff to live many miles from their work, We have tried to raise a force of volunteers and ask them to give their time and their cars to help their colleagues.6

  In other words, the core of these teething problems was the fact that the codebreakers were finding it difficult to adjust to the change from fast metropolitan life to what many of them regarded as a provincial backwater.

  It is broadly assumed nowadays that the work at Bletchley required its inmates to be near-autistic, socially inept geniuses. In fact, the more prized quality would have been a certain nimbleness and litheness of mind, the ability to approach and solve a problem from hitherto unconsidered angles.

  This was certainly the case with Enigma. The breaking of the German codes would turn out to be the result of a combination of flashes of logical and mathematical insight plus a certain psychological brilliance. And this is even without mentioning the formidable technical skills of the men who built the “bombe” machines, the vast, revolutionary proto-computer constructions that could sift through the dizzying millions of potential combinations of each code.

  Nor was it just codebreakers who were needed. Bletchley Park also required the services of able, fast-witted linguists—young men and women fluent especially in German.

  It also needed stalwart administrative backup: people who could attend to the grindingly tedious yet crucial roles of filing and archives. For not only were there enemy transmissions to be logged, translated, decoded—they also had to be filed in such a way that they could be cross-referenced with other messages in the future. At the beginning, this was a role that largely fell to the higher-class sort of “gel.”

  There was no embarrassment about this extension of the upper-class “shooting party” idea. Debutantes and daughters of “good families” were actively sought after, apparently to ensure the very highest levels of security and secrecy; Alistair Denniston felt that the smarter girls would have a more acutely refined sense of duty. Such wildly generalized social assumptions were not unusual at the time. But questions of class aside, that sense of duty led these well-bred girls to undertake with great good humor some of the most breathtakingly tedious work.

  On top of all this, the Park needed secretaries, office managers, and messengers, even waitresses for the canteen of the House. Quite a lot of people, all in all, to descend on a very small, un-noteworthy town.

  3 1939: Rounding Up the Brightest and the Best

  Almost instantly, Commander Denniston found himself sinking in a quagmire of difficulties. Indeed, he complained at the time that he was “most anxious to take my share of the work on the increasing numbers of cryptographic problems confronting us.” Such a desire was simply not practical.

  So, on September 4, 1939, further summonses to Bletchley started to go out discreetly. A surviving memo states: “Immediate personnel for Hut 3: I suggest 15 people be asked for at once. As you know I have already approached Pembroke College Oxford and they have promised to send me some names in a few weeks time.”

  This need for discretion was paramount, which is why so many of the first codebreaking and translating recruits were known personally and socially to their recruitors. But there was much more than just plain nepotism and snobbery going on. For the linguists recruited to translate the German messages, there is a suggestion that the security services played a part in the approaches. Certainly, reasonably stringent background checks were made on these early young arrivals. Other than this, though, there seemed to be a pleasing breeziness about the way candidates were picked.

  Mavis Batey is one of the few people to have worked closely alongside the volcanic Dilly Knox, and she herself was to play a key role in the Park’s story. She was by n
o means a debutante. Rather, she was a fiercely intelligent middle-class girl.

  Today Mrs. Batey, whose husband, Keith, is a fellow Bletchley Park veteran, is wryly amused by the reasoning that led to the Park’s upper-class recruitment drive: “The first two girls in the Cottage were the daughters of two chaps that Denniston played golf with at Ashtead. Denniston knew the family, he knew that they were nice people and…well, that their daughters wouldn’t go around opening their mouths and saying what was going on. The background was so important if they were the sort of people who were not going to go around telling everyone what they were doing.”

  For Keith Batey, a twenty-year-old undergraduate reading mathematics at Cambridge—who was to participate in some of the greatest inspirational leaps made at the Park, and who was to meet his future wife, Mavis, there after a chance encounter in one of the huts—his own recruitment was reasonably straightforward. So much so, in fact, that unlike many of his fellow codebreakers-to-be, he realized instantly as soon as he received the summons. He recalls: “They [the university authorities] were allowing mathematicians to stay on to finish degrees. I took my maths finals in Cambridge in May 1940—it all seemed highly artificial, with the Germans charging across Europe—anyway, I took it and then one had to wait to be told what to do.

  “I went home to Carlisle. A letter arrived, scruffily handwritten, from a chap called Gordon Welchman. He was writing to offer me a job. He couldn’t tell me what it was, where it was, or anything of that kind, but he could say that it was very important, very interesting, and that the pay was lousy.

  “Such was the security,” continues Mr. Batey with a certain dryness, “it was well known among the maths undergraduates in my year in Cambridge that in January 1940, one Welchman had taken a couple of his own graduates off to a certain ‘Room 40.’ And I knew Room 40 was cryptography.”

  His wife-to-be, a linguist and student of German literature, also had the benefit of a certain amount of inside knowledge. Just as the war broke out, she had been seconded to the old GC&CS near St. James’s Park—a distinctly unusual position for a young woman at that time. “I worked at Broadway Buildings first, in the Ministry of Economic Warfare,” Mrs. Batey says. “The job involved blacklisting all the people who were dealing with Germany—through commodities they were using. Then I got called for the interview at the Foreign Office—conducted by a formidable lady called Miss Moore—I don’t know whether she knew what we were going to do. At the time of the interview, we didn’t know whether we were going to be spies or what. But then I got sent to Bletchley.

  “I didn’t want to go on with academic studies,” Mrs. Batey continues. “University College London [where she had been studying] was just evacuating to the campus at Aberystwyth, in west Wales. But I thought I ought to do something better for the war effort than reading German poets in Wales. After all, German poets would soon be above us in bombers. I remarked to someone that I should train to be a nurse. But that person told me: ‘No you don’t, you go and see someone at the Foreign Office. They can use your German.’ And so I did.”

  Harry Hinsley, who was later to become the official historian of British wartime intelligence, recalled being interviewed at St. John’s College, Cambridge, by Alistair Denniston and Colonel John Tiltman. Of this experience Hinsley said: “The kind of questions they asked me were: ‘You’ve traveled a bit, we understand. You’ve done quite well in your tripos. What do you think of government service? Would you rather have that than be conscripted? Does it appeal to you?’ “1

  This, at least, was rather more subtle than an approach made two years before to Professor E. R. P. Vincent, who was invited to dinner by Room 40 veteran Frank Adcock. Professor Vincent recalled: “We dined very well, for he [Adcock] was something of an epicure, and the meal was very suitably concluded with a bottle of 1920 port. It was then that he did something which seemed to me most extraordinary: he went to the door, looked outside, and came back to his seat. As a reader of spy fiction, I recognized the procedure but never expected to witness it.”2

  However corny, the approach worked, and Professor Vincent was to join the team engaged with wrestling with the Japanese codes.

  For Sheila Lawn there was a definite element of taking an active role in the conflict. “I was in my second year in Aberdeen University studying for a Modern Languages honors degree. But I was very troubled because I was reserved as a future teacher. I felt I ought to be doing something—like so many of my friends—about fighting Hitler. So I took my name away from the Reserve list, didn’t consult anyone, just took it away. I waited for developments, which came very quickly—a letter from the Foreign Office in London, asking me to go down for an interview.

  “I had my interview,” Sheila continues. “And shortly after that—it was the vacation—I got another letter, simply asking me to report to Bletchley.”

  The man whom she met at Bletchley Park, and whom she was later to marry—Oliver Lawn—was similarly young and eager when he found himself being approached. Mr. Lawn was later to find himself overseeing one of the most important technological breakthroughs of the entire war. But for this young man, only nineteen years old, not long out of a respectable minor public school, there was little hint at the beginning of the intellectual excitement that lay ahead.

  Now he finds himself recalling the start of his Bletchley Park career with a certain amused seriousness. “At the time, I was doing maths tripos at Cambridge. When I finished my tripos, my Part Three, in 1940, I expected to be called straight up into the army—Engineers or whatever. When I went up to Cambridge in July to take my degree, I was asked to go and see a chap called Gordon Welchman, who I knew by name, but not in person. He was a mathematics lecturer, who had not been one of my lecturers.

  “So I didn’t know, of course, that he had gone to Bletchley. I went to his room, and he said: ‘Would you like to work with me?’ Without telling me, of course, what the work was. Obviously, since I was due for call-up, I had no choice, in that sense. And a fortnight later, I turned up at Bletchley Park, and sat at Welchman’s feet, to learn about Enigma.”

  For the Honorable Sarah Baring—a young debutante, goddaughter of Lord Mountbatten, and a photographic model for Cecil Beaton—the route to Bletchley Park was a little less cloak-and-dagger and rather more patriotic gung ho. As soon as the war broke out, she knew that she wanted to throw herself into the effort. The only problem was that the first job she found was less than ideal.

  “When the war started, me and a great friend of mine, Osla Henniker-Major, decided we wanted to do something really important,” Sarah Baring says. “And we thought: making aeroplanes. So we trooped off to the Slough Trading Estate—ghastly place—and said to the people there: ‘Here we are—we want to make aeroplanes.’ So we were shoved into something like a school.

  “We had to learn how to cut Durol,” she continues, “which the planes were made of. We did that for a while, and then Osla and I felt we weren’t really doing enough. Then suddenly, through the post, came a letter, God knows who from, asking us to report to the head of Bletchley—forthwith. That was all. So we thought: ‘Anything’s better than making aeroplanes at the moment.’

  “We had to have a language test,” she continues. “And it was a funny one. I knew German, luckily, because my mother had sent me to Germany when I was sixteen—I hated it, by the way—so I had the German. And French was easy. And I suddenly realized that the lady who was talking to me and finding out about my linguistic skills didn’t have a clue what she was talking about.

  “So I lost my head completely and said: ‘Oh! Would you like to hear my Spanish?’ I couldn’t really speak Spanish at all. She said: ‘Oh no, dear, I think that’ll be—’ I added: ‘I can do Portuguese.’ The whole thing was going to my head. She said: ‘No, no, dear, that’s fine, you’ve passed the thing.’ It was the German this lady was after, of course.”

  Others too found that the language test didn’t seem to be as rigorous as one would expect. One recruit
was asked if she could speak Italian. “Only opera Italian,” she replied. “Yes, that will do,” she was told.

  One young mathematician did have an idea of what was coming, and his approach was more cloak-and-dagger than almost anyone else’s. But as the man who would provide one of the most brilliant intuitive leaps of the war, this is perhaps appropriate. John Herivel—whose “Herivel Tip” was to prove vital in the struggle to crack Enigma—remembered his introduction to the institution as a young undergraduate in 1940: “Gordon Welchman in the early days had done most of the recruiting. A lot of them inevitably were people that he knew. The men and also, I think, some of the women.”

  Welchman also happened to be Herivel’s old mathematics lecturer, so the link could not have been more direct. From the undergraduates’ point of view, he was a figure who had disappeared from the university under a cloud of mystery; now, one cold midwinter’s evening in Cambridge, twenty-one-year-old Herivel got an unexpected visit in his room from the very man himself.

  Welchman was brisk, though civil, wasting little time in telling Herivel that there was important war work going on at Bletchley Park and asking him if he would like to come and help.

  The young man responded equally briskly; Mr. Herivel recalls that at that time “the university was a ghostly place,” and that Part III of his Mathematics tripos could wait until after the war. And so a date was agreed. Welchman told Herivel where to go and whom to present himself to, and just a few moments later, the former Cambridge lecturer was gone, with a cheery “au revoir.”

  Several days later, Herivel was on the train from Cambridge to Bletchley, speculating madly about what he was getting into. “The very first thing I had to do on arrival there,” he recalls, “was swear an oath. About not revealing a single detail to anyone. I remember there was a fearsome looking naval officer there—presumably to instil a measure of fear!”