A GREEK TOY.
Mechanism of the Toy.—Let Α Β be the water-tight pedestal under consideration, provided with a diaphragm, Γ Δ. To this latter there is fixed a small, hollow, truncated cone whose apex points toward the bottom of the vessel, and from which it is just sufficiently distant to permit the water to pass. To this cone there is adjusted with care another one, Θ, which is fixed to a chain that, passing through an aperture, connects it with the apple. Hercules holds a small horn bow, whose string is stretched and laced at a proper distance from the right hand. The left hand is provided with a detent. To the extremity of this latter there is fixed a small chain or a cord that traverses the top of the pedestal, passes over a pulley fixed to the diaphragm, and connects with the small chain that joins the cone with the apple. This cord passes through the hand and body into the interior of Hercules. A small tube, one of those used for whistling with, starts from the diaphragm, rises through the top of the pedestal, and passes into the interior of the tree or around it.
Now, if the apple, Κ, be raised, the cone, Θ, will be raised at the same time, the cord, Χ Φ, will be tightened, the catch will be freed, and this will cause the arrow to shoot. The water in the compartment Α Γ, running into the compartment Β Γ, will drive out the air contained in the latter, through the tube, and produce a hissing. The apple being replaced, the cone, Θ, will adjust itself against the other, stop the flow, and thus cause the hissing to cease. The arrow and its accessories will then be adjusted anew.
When the compartment Β Γ is full, it is emptied by means of a spout provided with a key, and Α Δ is again filled as we have indicated.
THE DECAPITATED DRINKING HORSE.
The optical delusion known as the talking decapitated person has already been described in [Book I., Chapter I.], of the present work. The ancients invented an analogous trick, but one that was founded upon a very ingenious mechanical combination. This is found described at the end of Heron’s “Pneumatics,” under the title, “To cut an animal in two and make him drink.” It is as follows:
“Let us suppose a hollow pedestal, A B C D, divided in its center by a diaphragm, E F. Above the pedestal there is fixed a statuette representing a horse and traversed by a tube, M N, which terminates on the one hand in the horse’s mouth, and in the other in the upper part of the compartment, A B E F, after following one of the legs. It will be conceived, in the first place, that if the said compartment be filled with water through an aperture, T, which is afterwards stopped up, and that then a cock be opened, so as to form a communication between the upper compartment and the lower (which latter is itself provided with an open air-hole), the water will flow, and, in doing so, tend to cause a vacuum in the tube, M N, so that when a vessel of water is brought near the animal’s mouth the water will be sucked up.