“In Figs. _1a_ and _1b_ (elevation and plan), the wheels E and M have each a train of clockwork (left out for the sake of clearness), which would cause them to spin round if unchecked. M, however, has two pins, _p p_, which catch on a projection on the lever, N. E is a crown-wheel escapement—like that in a bottle roasting-jack—which turns A alternately to the left and right, thus causing the hand to traverse the thirteen cards. A little higher up on A will be seen a quadrant, B (see plan), near the edge of which are set thirteen little pins. The end of the lever, N, drops between any two of them, thus causing the hand to stop at any desired card. The lever being pivoted at _c_, it is obvious that by depressing the end, N, B will be set at liberty, {118} and the hand will move along the cards; by slightly raising it this motion will be arrested; by raising it still more the pin, _p_, is released, and M commences to revolve, and by again depressing N this wheel will, in its turn, be stopped. Near the bottom of the apparatus is a bellows, O, which contains a spring tending to keep the lever, N, with which it is connected by a rod, X, in the position shown. This is connected with the tubular support, which may be connected by a tube through the leg of the stool, and another tube beneath the stage, with an assistant behind the scenes. By compressing or exhausting air through this tube it is obvious that the lever, N, will be raised or depressed, and the clockwork set going accordingly. _a_ is a crank-pin set in M, and connected with the head by catgut, T, and with the thumb by S. At R and R are two pulleys connected by gut. Thus if the {119} hand moves round, the head appears to follow its motions, and when raised by pulling S, the head rises also by means of T. Further explanation seems almost unnecessary; _l_ is a stop to prevent the elbow moving too far, and _b b_ spiral springs, to keep the thumb open and the head forward respectively. When N is raised, M pulls T and S, the latter closing the thumb, and then raising the arm by pulley H. If the lever is allowed to drop, _p_ will catch and keep the arm up. On again raising N, the arm will descend.