My third book, The Mechanical Turk, will be out in April. (It will be called simply The Turk in the US.) The book tells the story of the chess-playing machine built by Wolfgang von Kempelen, a Hungarian nobleman, in 1769 in response to a challenge from Maria Theresa, empress of Austria-Hungary. It defeated Napoleon, Benjamin Franklin and Charles Babbage, among many others. But could a machine really play chess, or was it all a hoax? The Turk, as the machine became known, caused a vigorous debate about the possibility of machine intelligence 150 years before the first computers were constructed.