'The word "clue",' Kate Summerscale writes, 'derives from "clew" meaning a ball of thread or yarn.' In mid-Victorian England, clues were satisfying objects to be grasped, then unknotted or unravelled. Clues pointed the way to go. On his way into the Minotaur's labyrinth, Theseus unravels a ball of red thread given him by Ariadne, so that he can find his way out again, gathering the thread as he goes. By the 19th century, it was thought desirable to untangle a clue - separate out the thread from the ball - rather than gather it up as Theseus had done. In David Copperfield, Mr Wickfield tells David he will 'unravel' a clue. In Great Expectations, Dickens refers to a napkin being wielded like a 'magic clew', leading 'the way upstairs'. In The Moonstone, Gabriel Betteredge laments 'a clue that had broken in our hands'. If there were clues, there were also pseudo clues, leading down blind alleys, pointing away from the truth.

LRB 19 June 2008 | PDF Download