Modern Magic: A Practical Treatise on the Art of Conjuring

by Professor Hoffmann

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.

Fig. 309.

Fig. 310.

The box measures about ten inches in length, by five in breadth and five in depth, so that its back, front, top, and bottom are of exactly the same size. On the top, which slides out, in order to give access to the interior, is an ornamental design, measuring about four inches by three. This renders this particular portion of the top or lid opaque, and it is beneath this portion that the half-crowns are placed. Slips of glass are cemented to the under side of the lid (see [Fig. 309]), so as to inclose a space just large enough to allow eight half-crowns to be placed, in two layers of four each, within it. The slips of glass serve to keep the coins in position laterally. Vertically, they are supported as follows:—The front of the box (i.e., the side which, when the box is suspended, is nearest to the spectators) is made double. The outer portion is a fixture, but the inner is attached by hinges a a to the upper edge of the box, and may therefore be folded at pleasure against the top, though when released it falls back to its normal position against the front, in which position it is secured by a spring catch until again raised. It is upon this moveable side, thus folded up against the top, that the eight half-crowns are supported. The opposite edge of the top of the box is arranged as follows: b b is a metal tube, with an opening of about half-an-inch in length between d d; c c are two metal hooks or rings by which the apparatus is suspended, and through which the current passes. Each of these communicates with a piece of insulated copper wire, extending from c to d. The space between d d is filled up by a round plug or pencil of wood (see enlarged view in [Fig. 310]), along which lies a small piece of very fine platinum wire e e, connecting the ends of the two copper wires. The moveable glass flap is held up against the top by means of a little piece of black cotton f, which, passing through a minute hole in the outer edge of the flap, is made to pass round the wooden plug, and thus to cross the platinum wire at right angles, and in immediate contact with it. The practical application of the scientific principle to which we have alluded will now be obvious. At the moment of completing the circuit, the platinum, becoming red-hot, instantly severs the cotton, when down falls the flap, not altering in the least the general appearance of the box, but allowing the half-crowns to fall loose into its interior.

In order to prepare the apparatus for use, it is necessary first to remove the sliding lid, to place the moveable flap in position, and to fasten it with cotton as already described. The lid should then be turned upside down, and the half-crowns placed in position, after which the box also is turned upside down, and the lid allowed to slide gently into its place. The half-crowns are now secure, and the box may be brought forward and set swinging, without any danger of their making a premature appearance.

In some boxes the double flap is omitted, the front being single, but moveable, and working as already explained. In this case the box, when first brought forward, has the glass of the side towards the audience missing, but at a little distance its absence cannot be detected.

The Magic Drum.—This is in appearance an ordinary side-drum, but being hung up by cords from the ceiling, it will forthwith, without any visible drumsticks, give either a single rap or a roll, or keep time to any piece of music. It will further answer questions and tell fortunes, indicate chosen cards, etc., after the manner of the magic bell.

These mysterious effects are produced by two hammers or drumsticks, fixed against one end of the drum on the inside. Each of these is attached to the keeper of an electro-magnet, but there is a difference in the mode of their working. One works after the manner of the bell, giving a single tap whenever contact is made, but thenceforward remaining silent until the circuit is again broken and again completed. In other words, each pressure of the connecting stud produces one rap, and no more. The second hammer is differently arranged. By means of what is called a “contact-breaker,” the movement of the keeper, when attracted by the magnet, of itself breaks the circuit. The circuit being broken, the iron is no longer magnetic, and the keeper flies back to its old position, thereby once more completing the circuit. As long as the pressure on the stud continues, therefore, the circuit is alternately made and broken in rapid succession, involving a corresponding movement of the keeper and hammer, and producing a “roll” of the drum. The use of the two hammers involves the necessity of two electrical circuits and two connecting studs, and of three cords to suspend the drum (one being common to both circuits). With a little practice in the management of the two studs, the single rapper may be made to beat time to a tune, while the other stud brings in the roll at appropriate intervals.