story writer) F. W. Winterbotham, RAF Intelligence Officer, responsible for devising SLU system for secure dissemination of Ultra (author of The Ultra Secret) Shaun Wylie, arrived at Bletchley in February 1941, head of crib section in Hut 8, transferred in Autumn 1943 to work on Tunny (topologist, mathematics lecturer at Cambridge, and head of mathematics at GCHQ) C. E. Wynn-Williams (physicist from the TRE; designed the electronic counters used in the Newmanry's Robinson machines and Colossus computers Leslie Yoxall, Hut 8, devised Yoxallismus technique Joan Louisa McLean, Leading Wren 45270, wartime morse code operator See also List of women in Bletchley Park See Hut 7 for a list of those associated with Japanese codes and either the Far East Combined Bureau or Wireless Experimental Centre in the Far East. References Further reading 'Buckinghamshire Spies and Subversives' by DJ Kelly (May 2015) see ch. 13 Lists of British people Bl Lists of World War II veterans Bletchley Park Lists of English people by location