AGD and son Robin with golf clubs, 1936

A transcription of the Zimmerman telegram in 1917. Intercepted by British codebreakers, it was instrumental in persuading the USA to declare war on Germany.

Signal to the Director of the Iintelligence Division of the Naval Staff from M.I.1.B., July 13 1917

(Back row) AGD’s father and mother-in-law. Between them, the author’s mother and (centre) the author. On the right (back) AGD’s mother, AGD and daughter ‘Y’ in 1931.

AGD’s family outside their home at 48 Tedworth Square, London, 1936

AGD’s wartime passport photograph

AGD (left) with Professor E.R.P. Vincent, one of the Hut 4 Italian experts (centre), and Colonel John Tiltman, the brilliant codebreaker.

AGD’s 1939 passport, now on display at Bletchley Park

The entries in AGD’s diary in August 1941 when he flew to the USA for a meeting with codebreakers there.

Memo to AGD prior to USA visit, 5 August 1941 (author unknown)

AGD memo, 29 September 1941, following his visit to USA

Bletchley Park staff c1940/41: seated (left to right), E. M. Smith, Edmund Green, Barbara Abernethy, Patrick Wilkinson and Alan Bradshaw; standing (left to right), Philip Howse, Stephen Wills, Captain Ridley, John Barns, George McVittie, Marjorie de Haan and A.G. Denniston, head of GC&CS.

Extract from US Embassy, London, memo June 6 1943 concerning Arlington Hall’s liaison with Berkeley Street

Bletchley Park (above, and below, plan of the grounds)

AGD memo to Washington, 23 December 1941.

Intercepted cable from Japanese Foreign Minister to Japanese Embassy in London, dated 25 November, 1941. NB Churchill’s annotated footnote: ‘Fear! Fear may not prevent, may even provoke, action. But it is a fact all the same.’

Kim Philby at a press conference in 1955

AGD at his daughter’s wedding in 1958

‘D.G.’ was Dorothy Gilliat, one of the five children of a successful Leeds businessman, Arthur Gilliat, himself the youngest of ten children. ‘D’ as she was known to her sisters, born in 1891, was the clever one and went up to read English at Lady Margaret Hall, Oxford. She was a beauty and had many admirers, most of whom died in the Great War. Her closest friend was my father’s sister, Biddy Briggs. Through Biddy ‘D’ met my father. They were married in 1917. After the war, they lived in Chelsea, moved out of London to the outer suburbs because of my health in 1936, and lived near BP from 1939 till 1942. ‘D’, a linguist with good French and German and an excellent English writing style, worked as a watchkeeper at BP till my father’s job required him to return to London. She was the soul of discretion, She sent us a telegram in late 1957 to say she had a mammary tumour, from which she died a few months later. Her only obituary called her ‘one of the quiet ones’. She was a wonderful mother. R.I.P.