The mechanism is almost identical with that shown in the modern device; in fact, this ancient vase, described by Heron more than two thousand years ago, is the prototype of all modern automatic vending machines, and simply serves as another proof of the truth of the saying, “There is nothing new under the sun.”
It is a curious fact that this ancient invention escaped the notice of the Patent Office until long after patents were granted for the earlier automatic vending machines. It was only a comparatively short time ago that the Patent Office began to cite the vase of Heron as a reference. It was discovered in an ancient work on natural philosophy, and it is a matter of considerable interest to us now to know that this device was well-known to the Patent Office during the middle of this century. The vase of Heron is illustrated and described in a work on hydraulics and mechanics published in 1850 by Thomas Ewbank, who was at that time Commissioner of Patents.
AN EGYPTIAN LUSTRAL WATER VESSEL.
Two thousand years ago the Egyptian priests sold holy water to the faithful by a similar process to that which we have just described, although the apparatus did not partake of the nickel-in-the-slot character. Heron says of them, that there are placed in Egyptian sanctuaries, near the portico, movable bronze wheels which those who are entering cause to revolve “because brass passes for a purifier.” He says that it is expedient to arrange them in such a way that the rotation of the wheel will cause the flow of the lustral water. He describes the apparatus as follows:
EGYPTIAN LUSTRAL WATER VESSEL.
“Let Α Β Γ Δ be a water vessel hidden behind the posts of the entrance doors. This vessel is pierced at the bottom with a hole, Ε, and under it there is fixed a tube, Ζ Η Θ Κ, having an aperture opposite the one in the bottom of the vessel. In this tube there is placed another one, Λ Μ, which is fixed to the former at Λ. This tube, Λ Μ, likewise contains an aperture, Π, in a line with the two preceding. Between these two tubes there is adapted a third, Ν Ξ Ο Ρ, movable by friction on each of them, and having an aperture, Σ, opposite Ε.