An Improved Psycho.
Let me explain to those who have not seen “Psycho” that it consists of a small figure dressed as a Turk, sitting cross-legged (as shown by dotted lines) on a chest; this chest is in turn supported on a glass tube, about 12 in. in diameter and 3 ft. long, which rests on a four-legged stool. The bottom of chest and top of stool are covered with green cloth, so as to make a tolerably air-tight joint. The right arm is extended as per drawing, and a semicircular rack, in which are placed the 13 cards dealt to “Psycho,” is fixed by means of a bracket (not shown) in such a position that the edges come between the finger and thumb, as shown at *. The arm turning horizontally on the pivot A, the hand can be brought over any card, and by closing the finger and thumb and raising the arm the card will be withdrawn from the rack and held in the air.
FIG. 1. a.
FIG. 1. b.
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 13 cards. A little higher on A will be seen a quadrant B (see plan) near the edge of which are set 13 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 pressing the end, N, B will be set at liberty, 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 crankpin 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 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 thumb open and head forward respectively. When N is raised M pulls T and S, the latter closing thumb, and then raising arm by pulley H. If the lever is allowed to drop p′ will catch and keep arm up. On again raising N the arm will descend.
FIG. 2. a.
FIG. 2. b.
Figs. 2a and 2b show another and simpler arrangement, in which only one train of clockwork is used. On the same axle as H is fixed a lever and weight, W, to balance the arm. A vertical rod, X, having a projection, Z, slides up and down in guides, Y Y, and carries the catgut S and T. The quadrant, B, has cogs cut, between which Z slides and stops the motion of A, which is moved, as before, by clockwork. The lower part of X is connected direct with O. When X is slightly raised, as shown, A is free to move, but on exhausting air and drawing X down Z enters the cogs and stops the hand over a card; continuing to exhaust the thumb closes and the card is lifted up. The details of the clockwork I leave to the ingenuity of your readers. There should be a fan on each train to regulate the speed. The figure should be so placed that your assistant can see the cards in the semicircular rack.—English Mechanic.