Modern Magic: A Practical Treatise on the Art of Conjuring

The secret lies in the use of an ingenious little piece of apparatus, which is placed in the waistcoat pocket of the performer, and from which the sound proceeds. This apparatus, which is represented in Fig. 105, consists of a short brass cylinder (about an inch and a quarter in depth, and two inches in diameter), containing a small clock-bell, with the necessary striking mechanism, which is wound up beforehand with a key, after the manner of a watch. This mechanism is set in motion by pressure on the button a, the hammer continuing to strike as long as the pressure is continued, but ceasing as soon as the pressure is removed. The cylinder, which is perforated all round, in order to give free passage to the sound, is placed upright in the left pocket of the performer’s waistcoat, which should be just so tight around the ribs that the mere expansion of the chest shall cause the necessary pressure against the button a, the pressure ceasing when the chest is again contracted. (The placing of a playing-card in the pocket for a to rest against will be found to facilitate the arrangement.) This is the whole of the secret. In working the trick the performer has only to take care to hold the watch in a tolerably straight line between the pocket and the audience, when, the line in which the sound travels being the same as if it actually came from the watch, it will be almost impossible to detect the deception.