In this trick, pairs of cards are placed between the fingers of a spectator's hands, and then removed very fairly to form two equal piles. An extra card is added to one pile and caused to travel mysteriously to the other pile. This trick has the feel of being quite old, but descriptions of it prior to the 1900s have been elusive. Philippe Billot has tracked one down: “The Odd Card” in What Shall We Do To-night?, 1873, p. 30, by “Leger D. Mayne”, the pen name of William Brisbane Dick. Dick gives no history or attribution for the trick.
T. Nelson Downs is recorded by Barrows Mussey, in his book Magic, 1942, p. 45, as claiming the name “Piano Trick” was attached to the trick by Imro Fox.