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The idea of causing the backs of the cards in a deck to change to fifty-two differently colored backs as a surprise climax to a routine is Clarke “The Senator” Crandall's, who first contributed in under the title of “A Backward Effect” to Abracadabra, Vol. 6 No. 140, Oct. 2 1948, p. 156. It was later reprinted in the U.S. in The New Phoenix, No. 328, Aug, 8, 1955, p. 120.