28. An Automaton which drinks at certain times only, on a Liquid being presented to it.
In any place provided with running water make a figure of some animal in bronze or any other material: when a cup is offered to it, the animal shall drink with a loud noise so as to present the appearance of thirst. The following is the construction. A B (fig. 28) is a vessel into which a stream of running water, C, falls. In A B place a bent siphon or inclosed diabetes, D E F, one leg of which must project below the bottom of the vessel. Underneath this let there be an air-tight pedestal, G H K L, also containing a bent siphon, M N X. Below the orifice F place a funnel, O P, the tube of which must descend into the pedestal leaving a passage for the water between its extremity and the bottom. Let the mouth of the animal be at R, from which a concealed tube, R S T, must run along one of the feet, or some other part, into the pedestal. When the vessel A B is filled, the water will overflow and run into the funnel, filling the pedestal G H K L and emptying the vessel A B; in like manner, when the pedestal is full, the water will overflow through the siphon M N X and empty the pedestal; and, as this becomes empty, the air will enter through the mouth R to fill up the void that is left. If, then, we apply a drinking vessel at R, the liquid will be violently attracted and sucked down instead of the air, until the pedestal within has become empty. Then the vessel A B is again filled and emptied, and the same will take place as before. In order that the cup may be applied at the right time, that is, when the water is being drawn off from the pedestal, let something be contrived that will move when struck by water from the discharge through the siphon M N X. When this is seen to move, apply the drinking cup.