Fig. 276.
The above are the traps in most frequent use, but there are others designed for special purposes. Thus there is a trap for causing the disappearance of six or eight half-crowns (as, for instance, in the well-known trick of the “[crystal cash-box],” which will be described in the course of the present chapter). Of course the coins could be made to disappear through an ordinary trap, but they would cause a suggestive “chink” in their fall. The trap to which we are now referring (see [Figs. 275] and [276]) is designed to prevent this tell-tale sound, and to cause the half-crowns to disappear in perfect silence. The opening in the surface plate is an inch and three-quarters in diameter, and is closed by a circular piston of brass or zinc, a, working up and down in a small brass cylinder b, and so arranged as to drop by its own weight to the bottom of the cylinder, save when kept up by a little lever catch at the side of the cylinder. A short pin d attached to this catch projects upwards through a slot in the surface plate, and stands up very slightly above the cloth of the table. The disc a being raised level with the surface plate, and secured by means of the catch, six or eight half-crowns or florins are placed on a. The performer, in making the motion of picking up the coins (with one hand), with the tip of the third finger pulls the pin d towards him. This withdraws the catch, and a instantly drops down to the bottom of the cylinder, carrying the coins with it. As soon as a reaches its lowest point, it draws down the pin e, thereby releasing a similar disc f, which, working laterally on a spring pivot at the edge of the opening, describes a semicircle, and assumes the position previously occupied by a, a portion of one side of the cylinder, at the top, being cut away to allow of its passage. [Fig. 275] shows the trap in its first, and [Fig. 276] in its second condition, the latter being, for greater clearness, drawn in section. The apparatus is rather complicated, and it is almost hopeless to endeavour to render it clearly intelligible by description only. In the absence of this special trap, the same object may be nearly as well effected with an ordinary trap by using half-crowns (be it remembered that it is always substitute coins which are made to disappear in this manner) which have been beeswaxed on both sides. A very slight pressure will cause a number of coins thus prepared to adhere together, and form for the time being a solid mass, which will fall through the trap without causing any “clink.”
We next come to—
Fig. 277. Fig. 278.
Fig. 279.
Pistons.—These are appliances for working pieces of mechanical apparatus—as, for example, the Watch Target, the Card Star, the Demon’s Head, etc., etc. A piston (see [Figs. 277, 278]) consists of a brass tube a, about five inches in length by five-eighths of an inch in diameter, with a collar at one end pierced with screw-holes for affixing it to the under surface of the table. Within this tube works a wire rod, b, three-sixteenths of an inch thick, and terminating in a small round disc of brass c, just large enough to work freely up and down the tube. A spiral spring, also of brass, keeps the rod down, unless when forced upwards by pulling a piece of whipcord, which is attached to the disc c, and thence passes up the tube, and over a small pulley d, which is soldered to the collar already mentioned. When this cord is pulled, b is forced to rise, which it does to the extent of about two inches above the surface of the table (see [Fig. 278]), again sinking under the pressure of the spring, as soon as the pull is relaxed. Each piston is screwed to the under surface of the top of the table, in which a small hole is bored, in order to allow of the upward passage of the piston rod. Where complicated mechanical pieces have to be worked, three, four, or more of these pistons are placed side by side. The cords are carried behind the scenes, either directly from the back of the table, or down grooves in the legs, and through holes in the stage to the hiding-place of the assistant. Where a single piston only is required, it may be made to work in the central pillar of a light guéridon, or fancy table, such as shown in [Fig. 279], the lightness and simplicity of the table, and the thinness of its top, apparently precluding all possibility of the presence of concealed mechanism. The cord may be made to pass down the centre pillar, so as to be quite invisible to the audience.
Fig. 280.