Modern Magic: A Practical Treatise on the Art of Conjuring

There is another box (the invention of Robert-Houdin) which goes by the same name, and with still better title, inasmuch as not only the top and bottom, but the sides and ends, are of glass, held together by a light metal framework. In appearance it is as shown in Fig. 308, and, being transparent throughout, it appears physically impossible that any object should be concealed in it; and yet, when the box is suspended, and set swinging, the operator has only to take the (supposed) borrowed coins in his hand, and to pronounce the mystic “Pass,” when the eight half-crowns are seen and heard to fall into the box, and may be taken from thence by the owners themselves, without even this near inspection of the apparatus revealing the secret of their appearance. As in the trick we have just described, electricity is the motive agent; but in this instance it operates, not by its magnetic influence, but by another of its mysterious properties. If a tolerably powerful current be made to pass at some point in its circuit through a short length (say half an inch) of fine platinum wire, platinum being a bad conductor, the wire will, at the moment of completing the circuit, be heated to a white heat, or, if the current be very powerful, will even be fused altogether. A very few words will show how this simple scientific fact is made available to produce the desired result.