In the adventure of the Dancing Men, Sherlock Holmes decoded a
cipher which used symbols to encrypt a message. Codes and ciphers
have been used since Roman times to confuse the enemy - Julius Caesar
had a very simple code using a 'Caesar's Wheel'; Mary, Queen of Scots
had an intricate code which she used to contact her supporters in the
16th century; and most famously the 'Enigma' code was invented by the
Germans before the Great War. Some of the puzzles here are based
on those used by Bletchley Park Museum Trust and others are ancient but
well-known ciphers.
