Saturday, October 31, 2009

Book of the Day: Dilly - The Man Who Broke Enigma

From the new Biteback Publishing blog, written by the author of DILLY: THE MAN WHO BROKE ENIGMA, Mavis Batey. Mavis is 88 years old and worked at Bletchley Park.

Normally an obituary in The Times would provide a framework for a biography of an important person in any given field, but that simply wasn't true of the one written for my boss at the British wartime codebreaking base at Bletchley Park. This was the wonderfully eccentric but outstandingly brilliant Alfred Dillwyn Knox, known to his many friends and admirers simply as ‘Dilly’.

George Steiner, the American writer and philosopher, has described the codebreaking achievements that took place at Bletchley Park as ‘the single greatest achievement of Britain during 1939-1945, perhaps during the 20th century as a whole’. If that is true, then Dilly’s own achievements must be ranked among the greatest in their own right.

Dilly’s work on the various Enigma ciphers was certainly among the most important and significant carried out at Bletchley. Enigma was not one single cipher machine, as is often suggested, but a family of many different ciphers and it was Dilly and his research section, of which I was a proud member, who were asked to find a way into each new cipher as it appeared.
The failure of his obituary in The Times to do him justice when he died in early 1943 was caused by the absolute secrecy surrounding the work on Enigma. The obituary mentioned that his father was a former Bishop of Manchester; that his brother was Monsignor Ronald Knox, a famous Catholic theologian; and that another brother, ‘Evoe’, was editor of Punch. It also mentioned his work as a Classicist reconstructing the mimes of the Greek poet and playwright Herodas.

What it could not mention was that he was one of the leading members of Room 40, the Admiralty’s celebrated codebreaking section during the First World War, broke Bolshevik ciphers during the 1920s and 30s, and Enigma ciphers during the Spanish Civil War and Second World War. What it would certainly not have been possible to mention, even without the understandable secrecy, was that Dilly’s greatest triumph had not even taken place when the obituary was written.

Shortly before he died, in great pain from the cancer, Dilly broke the Enigma cipher used by the German secret service, the Abwehr. It was this that allowed MI5 and MI6 to manipulate the intelligence the Germans were receiving through the Double Cross System and fool them into leaving too few troops in Normandy to counter the allied landings.

Now that many more previously secret records have been released into the archives, I have at last had the chance to give my old boss the credit he deserves. I felt a strong sense of déjà vu in seeing once more the same secret enemy messages that we handled over sixty years ago, but then the secrecy was such that even I was unaware of the effect Dilly’s work had on the allied success in the war. I was determined in writing this book to ensure that what Dilly did was never forgotten.

Buy the book HERE.


Simon Harley said...

I do hope that Mrs. Batey has been scrupulously fair and accurate in her treatment of Knox's employers during the First World War. Most historians of Room 40 don't seem to have bothered.

Paul Waugh said...

Sounds like a fantastic insight from someone who was actually there. Thank God for people like Dilly - and Mavis.

Johnners said...

The Royal Mail generously delivered Dilly to me last week. Very good read for anyone with even the loosest interest in Enigma, or even the War more generally.

Alex said...

Funny thing is a couple of weeks ago, the meejah and Gordon Brown were telling us that it was Alan Turing who broke the Enigma cipher in WWII. The truth as this book shows was that Enigma was a series of machines and ciphers that were updated and cracked several times in the 1930's and 40's.

Anonymous said...

Good book great story I hope we have similar people doing similar service today.

Turing did do the important work of simplifying the method of breaking the code and devising the machines to do it. He was not alone, his work was improved on and he improved that in turn.
Turing was instrumental along with Tommy Flowers in building the first computer that read the German High Command codes. We were reading the messages before Hitler.

The Enigma machines in the Spanish Civil war were commercial machines.

Bletchley Park is well worth a visit.

Its nothing new to know that there were various different ways enigma was used by the German army airforce navy and u-boats. The Poles did important work up to 1939 and indeed were reading enigma up to just before Sept 39.

Unknown said...

Ahhhh Bletchley Park and all who worked in her. To them I doff my cap.

Simon Singh does a decent enough book with a chapter on Enigma. The Germans transmitted each day to all users a three number setting repeated in code - say L R F M K T. We knew M was L, K was R, T was F - it was a foot in the door. No key could be encrypted as itself - another help. The daily chat about the weather was also a help.

I have another book on Bletchley written by some of those there, a chapter apiece, but I can't lay my hands on it.

Between Silk and Cyanide by leo Marks is another great read. Leo was i'c decoding for messages transmitted to London by SOE agents in Europe. On his first day they gave him an actual field message to decode as a test. It took him all morning.

'Disappointing', said the examiner, the girls usually rattle them off in ten minutes with the key.'

'No-one said anything about a key' said Leo, nicely illustrating how weak the encryption was (and how smart he was). The book illustrates how brave too were the SOE agents in the front line - Noor Inyat Khan, Odette, Freddie Yeo-Thomas, Violette Szabo - they carve their names with pride alright.

Richard Havers said...
This comment has been removed by the author.
Tapestry said...

Victory has 1000 fathers. Defeat is an orphan.

Anonymous said...

``Turing was instrumental along with Tommy Flowers in building the first computer that read the German High Command codes.''

Turing had little to do with Colussus past the theoretical work on computing machines before the war, and did no design work omn it. Turing was doing some very interesting work at the time with AT&T on speech encryption, involving the injection of pseudo-random noise, which was unfortunately ahead of its time in terms of realisability.