Modern Magic: A Practical Treatise on the Art of Conjuring

If the wax is properly amalgamated, it should leave no mark on the card. CHANGING CARD-BOXES, AND TRICKS PERFORMED WITH THEM.--The changing card-box in its simplest form is a small flat box in walnut or mahogany. (See Fig. 50.) Its outside measurement is four inches by three, and not quite an inch deep. Inside it is just large enough to admit an ordinary-sized playing card. The upper and lower portions of the box, which are connected by hinges, are exactly alike in depth, and each is polished externally, so that the box, which, when open, lies flat like a book, may be closed either way up; and either portion will, according as it is placed, become box or lid in turn. Thus, by using a card which, unknown to the audience, has two faces--e.g., is an ace of hearts on the one side, and an ace of spades on the other--and placing such card in one side of the open box, you have only to close the box with that side uppermost, or to turn over the box as you place it on the table, to transform the card just shown into a different one. There is nothing in the appearance of the box itself to indicate that it has been turned, so to speak, wrong side up, and a very little practice will enable you to turn it over, as you place it on the table, without attracting observation.