Modern Magic: A Practical Treatise on the Art of Conjuring

It is obvious that the changing trap will be equally available to produce an object under an empty cover. The object to be produced will be placed in c as above, the piston in d going down empty, and that in c rising with the object upon it. 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.