Mrs Batey is to be congratulated on a well written and perceptive biography of Dilly Knox. It deserves to become one of the standard works on Bletchley Park.
Alfred Dillwyn "Dilly" Knox was a classical scholar of eccentric manner who was recruited as a codebreaker into "Room 40" of the Naval Intelligence Division at the beginning of World War I, where he contributed to many of the successes of that organisation. After the war's end, rather than returning to academe, he became a member of the Government Codes & Cypher School (GC&CS) and continued the developement of cryptanalytical techniques.
Dilly was a key participant on the British side in talks with the French and Poles over Enigma. He moved to Station X at Bletchley Park at the beginning of WWII. His skills were put to good use, including recruiting suitable people from civilian life as the organisation expanded. He did not fit easily into the larger system and argued with his superiors, his frustration probably exacerbated by knowledge that cancer would soon kill him. Latterly forced to work from home (his importance can be judged by the fact that this was allowed), he died in February 1943 having been appointed CMG shortly before.
Mavis Batey (Mavis Lever in 1939; she would meet Keith Batey at Bletchley) was one of "Dilly's Girls". Her achievement here is to use her personal knowledge of her subject, and of the work of Bletchley Park, to produce a balanced account of Dilly Knox's personality and achievements. Despite her obvious affection for Dilly, this is not a hagiography. She describes the awkward elements of his character, but puts his disputes with his superiors in proportion, something other recent writers, of a more journalistic bent, have failed to do. (With hindsight, Dilly's eccentricities probably resulted from mild Asperger's,like other BP geniuses, although Mrs Batey does not raise this).
She uses her own experiences to counterpoint the narrative, but never intrudes. The contribution that Dilly and his team made to victory at the Battle of Matapan is rightly given a chapter to itself, which Mrs Batey adroitly also uses to demonstrate how timely intercepts were fitted into operational outcomes.
Mrs Batey manages to include much telling detail. It is intriguing to discover that Dilly's wife (who as his secretary in WWI had to put up with his habit of taking baths in the office) encouraged him to stay in GC&CS when he was contemplating a return to Cambridge, thus paying an enormous service to her country. The accounts of Knox's fondness for Lewis Carroll, and his own Carrollian pastiches are amusing (though she seems unaware that such pastiches were common in Dilly's generation).
Anyone with any interest in Bletchley Park and the people who made it work should read this book.