It shows a transparent clock face, such as you see in any jewelry shop. Some magicians utilize only one hand, which permits the easy use of electricity or magnet, while others employ two and even three hands. When more than one hand is used the hours and minutes are indicated simultaneously and, if cards are pasted on the clock face, the largest hand is used to find the chosen cards. The clock may be placed on a pedestal, in an upright position, or hung in midair on two ribbons or strings. It can be hung on a stand made expressly for the purpose, on the style of a music stand, or it can be swung in a frame. In fact, as stated before, it is usually placed so as to facilitate the method of working. [Illustration: M. Jacobs, magician, ventriloquist, and bold imitator of John Henry Anderson. From a rare lithograph now in the Harry Houdini Collection.] When the cabalistic clock is taken off the hook or the stand on which it is placed, and handed to one of the spectators to hold, the latter places the hand on the pin in the centre of the glass face, and revolves it. The arrow or hand is worked by a counterweight, controlled by the performer, who has it fixed before he hands it to the innocent spectator. The clock can be purchased from any reliable dealer of conjuring apparatus, in almost any part of the world. For a clock worked by counterweight the hand of thin brass is prepared in the centre, where there is a weight of peculiar shape which has at the thin or tapering end a small pin. This pin is fixed permanently to the weight and can be revolved about the small plate on which it is riveted. Through this plate there is a hole, exactly in the centre. This hand has all this covered with a brass cap, and, to make the arrow point to any given number, you simply move the weight with your thumb. The pin clicks and allows you to feel it as it moves from one hole to another. With very little practice you can move this weight, while in the act of handing it to some one to place it on the centre of the clock face; and when spun, the weight, of its own accord, will land on the bottom, causing the hand to point where it is forced by the law of gravity. The plate on which the weight is fastened is grooved or milled, so that it answers to the slightest movement of your thumb. When the clock is on the stage and the hand moves simply by the command of the performer or audience, it is manipulated by an assistant behind the scenes, either by the aid of electricity or by an endless thread which is wrapped about the spindle and runs through the two ribbons or strings that hold the clock in midair. Some conjurers work the clock so arranged as to make a combination trick; first by having it worked by the concealed confederate; then, taking the clock off the stand and bringing it down in the midst of the audience. But for this trick you can use only one hand.