used rodding to decrypt intercepted Italian naval signals describing the sailing of an Italian battle fleet, leading to the Battle of Cape Matapan in March 1941. Admiral John Godfrey, Director of Naval Intelligence credited the Allied victory at Matapan to this intelligence; Admiral Sir Andrew Cunningham, who had commanded the victorious fleet at Matapan, went to Bletchley to personally congratulate 'Dilly and his girls'. Intelligence Services Knox In October 1941, Knox solved the Abwehr Enigma. Intelligence Services Knox (ISK) was established to decrypt Abwehr communications. In early 1942, with Knox seriously ill, Peter Twinn took charge of running ISK and was appointed head after Knox's death. By the end of the war, ISK had decrypted and disseminated 140,800 messages. Intelligence gained from these Abwehr decrypts played an important part in ensuring the success of Double-Cross operations by MI5 and MI6, and in Operation Fortitude, the Allied campaign to deceive the Germans about D-Day. Death Knox's work was cut short when he fell ill with lymphoma. When he became unable to travel to Bletchley Park, he continued his cryptographic work from his home in Hughenden, Buckinghamshire, where he received the CMG. He died on 27 February 1943. A biography of Knox, written by Mavis Batey, one of 'Dilly's girls', the female codebreakers who worked with him, was published in September 2009. Classified poetry Knox celebrated the victory at Battle of Cape Matapan with poetry, which remained classified until 1978. References Notes Citations Works cited (Updated and extended version of Action This Day: From Breaking of the Enigma Code to the Birth of the Modern Computer Bantam Press 2001) (Updated and extended version of Action This Day: From Breaking of the Enigma Code to the Birth of the Modern Computer Bantam Press 2001) (Updated and extended version of Action This Day: From Breaking of the Enigma Code to the Birth of the Modern Computer Bantam Press 2001) (Updated and extended version of Action This Day: From Breaking of the Enigma Code to the Birth of the Modern Computer Bantam Press 2001) External links Description of rodding at Frode Weierud’s CryptoCellar 1884 births 1943 deaths Alumni of King's College, Cambridge British cryptographers Companions of the Order of St Michael and St George People educated at Eton College People educated at Summer Fields School British papyrologists Pre-computer cryptographers Bletchley Park people Fellows of King's College, Cambridge Deaths from lymphoma Deaths from cancer in England