The Invisible Eye has a long history, and I owe a lot to various people for their help along the way. In chronological order:
Eithne Fearnley-Whittingstall, for her splendid translations of some of these stories;
Thom Tessier and Phil Edwards, who produced the first edition in 1981 from the decks of the sinking ship that was Millington;
Mike Ashley, for help with biographical details;
The late Richard Dalby, who supplied ‘The Mysterious Sketch’ for the first edition, and ‘The Burgomaster in Bottle’ for this one. His help with biographical details, and his information from French sources, have been invaluable for both editions;
David Brawn and Georgie Cauthery at HarperCollins, whose infectious enthusiasm for this kind of book has been so welcome.