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Bart Whaley credits this to Herbert Brooks “sometime before 1915,” with a mention of Arthur Buckley for a subsequent “non-apparatus version.” The card index itself he credits (“reportedly”) to Hofzinser, then J. M. Hartz, et al.
A method with a card index hidden in the lining of a top hat is described as “The Magic Hat” in R.P's Ein Spiel Karten, 1853, p. 25 of the Pieper translation. This was possibly influenced by Hofzinser's work. William Henry James Shaw's Magic and its Mysteries, 1893, p. 13, includes “The Gambler's Pocket”, which is the Any Card Called For plot using a piquet pack and an index in the form of extra pockets sewn inside one's normal coat pockets.