Modern Magic: A Practical Treatise on the Art of Conjuring

The construction of the other two vases will be quickly understood upon an inspection of Figs. 222, 223. a is the vase, and c the cover fitting loosely over it, but between these two is a well, b, made double, so as to fit at once into and outside of a, after a mode of construction which we have more than once had occasion to notice. There is a bayonet-catch at the lower edge of c, corresponding with a pin or stud at the lower edge of b, so that c may be lifted off either with or without b. There is a similar catch at the lower edge of b, corresponding with a stud at the bottom of a, but cut in the opposite direction to the other catch, so that the action of unlocking a from b locks b to c, and vice versâ. The vase a requires a special description. A shallow saucer of tin, d, just fits the interior of the vase, working up and down therein piston-fashion, but prevented from coming out altogether by the fact that the upper edge of a is slightly turned inwards all round. Below d is a spiral spring, whose action tends to force d to the top of the vase, as shown in Fig. 222. From the centre of d, however, there extends downwards through the spiral spring a piece of stiff wire e, with a crook, f, at the end. The foot of the vase is hollow throughout. If the saucer d is forced down by pressure from within, this wire, as soon as it reaches the position shown in Fig. 223, will hook itself within the foot of the vase, and so keep down d, until the crook is again released, when the whole will instantly return to the condition shown in Fig. 222. The bottom of the foot is open, so that the fingers can without difficulty find and release the crook when necessary.