Bletchley Park Naval Enigma
Four rotor German naval Enigma on display at Bletchley Park (Image – Magnus Manske)
The work done during the Second World War at Bletchley Park, a Victorian mansion in Buckinghamshire, England was so secret, the people who worked there didn’t talk about it to anyone. Some took the secret with them to their graves.

Winston Churchill called Bletchley Park his “goose that laid the golden egg and never cackled”. The “golden egg” was the ability to decode the secrets of the German war machine. Station X, as it was known, was so efficient it could read coded messages from German generals on the battlefield before they were even seen by Hitler in Berlin.

And the Germans never suspected a thing – which was not surprising, given that they had invented the most complicated encoding machine the world had ever seen. Enigma, as it was called, looked like a large typewriter with lights. It could turn a message into unintelligible words that could only be decoded by using another Enigma machine with the same settings.

Thanks to a series of lettered rotors, which were reset each day, Enigma machines could be configured in 158,962,555,217,826,360,000 different ways. The Germans rightly thought it completely safe and uncrackable. View the video below for more information on how the Enigma machine worked.

As the war progressed, Station X became a hidden city of 10,000 people working in huts. Many of the codebreakers were mathematicians, but some were recruited because of their linguistic skills, knowledge of hieroglyphics, or brilliance at chess.

At the end of the war, all records of the place be destroyed in a huge bonfire. Had one former employee not written a book in 1974 (The Ultra Secret) about his work there, we might have remained in the dark about Bletchley to this day.

Alan Turing 1930
Alan Turing 1930 (Image in Public Domain)
Alan Turing, the genius who did most to crack the German Enigma codes and shorten the war by at least two years and in doing so saving an estimated 14,000,000 live,  also had a hand in the invention of the world’s first programmable computer at Bletchley, a giant machine called Colossus that enabled him to crack codes quickly, by a process of elimination.

Many people have heard of Alan Turing, particularly after the success of the film “The Imitation Game” depicting him and his work during the war.  He was part of an extraordinary team, many  brilliant. The second most important person at Bletchley was Hugh Alexander.
Alexander Hugh, like many of the codebreakers, he had a first in mathematics from Cambridge, but he found himself in Hut 6 in 1940 thanks to his brilliance at chess. Twice British chess champion, and an International Master, he made important contributions to two classic chess strategies: “the Dutch defence” and the “Petroff defence”. Had he been allowed to compete in the Soviet Union during the Cold War, he may even have become a world champion.He had a reputation at Bletchley for urbanity and charm. In 1941, he was transferred to Hut 8 and became Turing’s deputy.

Turing would tease Alexander for being almost, but not quite, his intellectual equal. According to a memoir written by one of his colleagues: “We all thought Hugh was crazy. Tall, blond, huge blue eyes, never stopped talking, a terrible energy.” And in the words of another: “We worked through the war on a continuous three-shift basis. The night shift was not generally popular because everybody quickly became tired through lack of proper sleep in the day; but Hugh had a strange passion for working at night and used to put himself on nights for weeks on end. This did not prevent him working much of the day as well – he seemed to thrive on this strange regime.” Alexander’s admiration for Turing was conditional – he found him annoying most of the time – and he eventually engineered a friendly coup against him to become the head of Hut 8. He did this because he rightly saw that Turing’s gifts were being wasted on the admin side of running things: he needed thinking space. It was Alexander, more than anyone else, who recognised Turing’s genius for what it was.

Alexander and Turing broke with protocol and went over the heads of their MI6 superiors to make a direct appeal to the Prime Minister, requesting more equipment and personnel. Churchill responded instantly, agreeing to the requests and notifying his Chief of Staff. His memo was stamped with that memorable phrase of his: “Action This Day.” When the Germans introduced a “super enciphered” method of transmitting the day’s settings to their Enigma operators , Alexander helped Turing develop a technique for breaking them. He died at the age of 64 in 1974.

Joan Clarke, by contrast, was a much calmer, less intense character, which is perhaps why she lived until 1996, long after she retired from GCHQ. Like Alexander, she had a first in maths from Cambridge; unlike him, when she was recruited to Bletchley Park she was told that her work there wouldn’t really require mathematics.

This turned out not to be the case. After a period of clerical work with, her mathematical gifts led to her becoming the only woman among a team of nine Banburists. And according to her boss, Alexander, she was “one of the best Banburists in the section”. Records describe her as “congenial but shy, gentle and kind and non-aggressive. Her enthusiasm and energy were legendary. She would often be reluctant to hand over her workings at the end of her shift and instead continue to see if a few more calculations would produce a result.

A pay rise was arranged to recognise her contributions to the team and she was promoted to “Linguist” even though she spoke no other language. She delighted in answering a questionnaire with “Grade: Linguist. Languages: none”.

In the spring of 1941, she developed a close friendship with Turing. For a time, they became inseparable, with Turing arranging their shifts so they could work together. One day, he proposed marriage to her and when Clarke accepted he added, “But don’t count on it working out as I have homosexual tendencies.” The romance continued regardless, until they called it off by mutual consent a year later.

Clarke became deputy head of Hut 8 in early 1944 and, after the war, she married an Army officer she had met when working at GCHQ.

Stewart Menzies, would be the next most important figure at Bletchley. His grandfather was a wealthy whisky distiller and his parents were friends of Edward VII. At Eton he was sporty but never academic.

Though not a codebreaker himself, he was in charge overall at Bletchley. He introduced a system called Ultra. If too many of the intercepts from Bletchley were acted upon, the Germans would get suspicious that the Enigma codes had been cracked. Menzies therefore introduced a system that meant only a certain percentage of the intelligence gleaned from decoding would be passed on to the British Army, Navy and RAF.

Peter Hilton, mathematician was recruited in 1942 at the age of 18 because he also knew German. He worked alongside Alan Turing in Hut 8 on Naval Enigma and, thanks to his  ability of visualisation, he was able to unpick in his mind’s eye streams of characters from two separate teleprinters – a feat  that proved vital when the Germans introduced a new system of teleprinter ciphers produced by a much larger and more complex machine than Enigma, called the Lorenz SZ40 encoder.
After the war, Hilton became a professor of mathematics at Cornell University. Once the Official Secrets Act was lifted in the Eighties, his lectures about the years at Bletchley Park became highly popular at venues all over the world.

“For me,” he recalled in one of them, “the real excitement was this business of getting two texts out of one sequence of gibberish. I never met anything quite so exciting, especially since you knew that these were vital messages.”

Jack Good was a thin, good-humoured, had a bushy-moustach and was a mathematician (Cambridge) who worked closely with Turing and was prone to having a quick sleep on the floor of the hut, especially after a long shift. This was just as well because he broke one vital code in his sleep, with the solution coming to him in a dream. When Good mentioned his discovery to Turing, the genius felt embarrassed, and said, “I could have sworn that I tried that already.” It quickly became an important part of the procedure.

After the war, Good became a professor and worked as a consultant to Stanley Kubrick on the 1968 film 2001: A Space Odyssey. He never guessed Turing’s sexual orientation in all the time they worked together, and neither did the Bletchley Park authorities. “Otherwise,” as Good noted matter-of-factly, “Turing may have been driven to kill himself earlier, and we might have lost the war.”

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