“Being given,” says Heron again, “two vessels, one of them containing wine, it is required that whatever be the quantity of water poured into the empty one, the same quantity of a mixture of wine and water, in any proportion whatever (two parts of water to one of wine, for example), shall flow out through a pipe.
“Let Α Β be a vessel in the form of a cylinder, or of a rectangular parallelopipedon. At the side of it, and upon the same base, we place another vessel, Γ Δ, which is hermetically closed, and of cylindrical or parallelopipedal form, like Α Β. But the base of Α Β must be double that of Γ Δ if we desire that the quantity of water shall be double that of the wine in the mixture. Near Γ Δ we place another vessel, Ε Ζ, which is likewise closed, and into which we have poured wine. The vessels, Γ Δ and Ε Ζ, are connected by a tube, Η Θ Κ which traverses the diaphragms that close them at their upper part, and which is soldered to these. In the vessel, Ε Ζ, we place a bent siphon, Δ Μ Ν, whose inner leg should come so near to the bottom of the vessel as to leave just enough space for the liquid to pass, while the other leg runs into a neighboring vessel, Ξ Ο. From this latter there starts a tube, Π Ρ, which passes through all the vessels, or the pedestal that supports them, in such a way that it can be easily carried under and very near the bottom of the vessel, Α Β. Another tube, Σ Τ, traverses the partitions in the vessels, Α Β and Γ Δ. Finally, near the bottom of Α Β we adjust a small tube, Υ, which we inclose, with the tube Η Λ, in a pipe, Φ Ξ, that is provided with a key for opening or closing it at will. Into the vessel, Ε Ζ, we pour wine through an aperture, Ω, which we close after the liquor has been introduced.
FIG. 4.—AN APPARATUS OF HERON PERMITTING OF MIXING WINE
AND WATER IN DEFINITE PROPORTIONS.
“These arrangements having been made, we close the pipe, Ξ Φ and pour water into the vessel, Α Β. A portion, that is to say, one-half, will pass into the vessel, Γ Δ, through the tube, Σ Τ, and the water that enters Γ Δ will drive therefrom a quantity of air equal to itself into Ε Ζ, through the tube, Η Θ Κ. In the same way this air will drive an equal quantity of wine into the vessel, Ο Ξ, through the siphon, Λ Μ Ν. Now, upon opening the pipe, Φ Ξ, the water poured into the vessel, Α Β, and the wine issuing from the vessel, Ο Ξ, through the tube, Π Ρ, will flow together, and this is just what it was proposed to effect.”
| FIG. 5.—MAGICAL VESSELS OF THE EIGHTEENTH CENTURY. | FIG. 6.—SECTION OF A MAGICAL PITCHER. |
The accompanying [figures], borrowed from a work on “Scientific Recreations,” by the late editor of La Nature, M. Gaston Tissandier, represents a magic vase and pitcher such as the ancients were accustomed to employ for the purpose of practicing a harmless and amusing deception on those who were not acquainted with the structure of the apparatus. For instance, if any one should attempt to pour wine or water from the pitcher shown in the cut, the liquid would run out through the apertures in the sides. But the person who knew how to use the vessel would simply place his finger over the aperture in the hollow handle ([Fig. 6]) and then suck through the spout, A, when the liquid would flow up through the handle and through a channel running around the rim of the vessel and so reach the spout. These magic vases, cups, pitchers, etc., were not only in use among the ancients, but were quite common in the eighteenth century, and numerous specimens are to be seen in European collections. The ones shown in the accompanying cuts are preserved in the Museum at Sèvres. These apparatus are all based on the use of concealed siphons, or, rather, their construction is based on the principle of that instrument. Devices of this kind admit of very numerous modifications. Thus tankards have been so contrived that the act of applying them to the lips charged the siphon, and the liquid, instead of entering the mouth, then passed through a false passage into a cavity formed for its reception below. By making the cavity of the siphon sufficiently large, a person ignorant of the device would find it a difficult matter even to taste the contents, however thirsty he might be. Dishonest publicans, whose signboards announced “entertainment for man and beast,” are said to have thus despoiled travelers in old times of a portion of their ale or mead, as well as their horses of feed. Oats were put into a perforated manger, and a large part forced through the openings into a receptacle below by the movements of the hungry animal’s mouth. Heron, in the eighth problem of his “Spiritalia,” figures and describes a magical pitcher in which a horizontal, minutely perforated partition divides the vessel into two parts. The handle is hollow and air-tight, and at its upper part a small hole is drilled where the thumb or finger can readily cover it. If the lower part of the pitcher be filled with water and the upper with wine, the liquids will not mix as long as the small hole in the handle is closed; the wine can then be either drunk or poured out. If the hole be left open for some time, a mixture of both liquids will be discharged. “With a vessel of this kind,” says an old writer, “you may welcome unbidden guests. Having the lower part already filled with water, call to your servant to fill your pot with wine; then you may drink unto your guest, drinking up all the wine; when he takes the pitcher, thinking to pledge you in the same, and finding the contrary, will happily stay away until he be invited, fearing that his next presumption might more sharply be rewarded.” Another old way of getting rid of an unwelcome visitor was by offering him wine in a cup having double sides and an air-tight cavity formed between them. When the vessel was filled, some of the liquid entered the cavity and compressed the air within, so that when the cup was inclined to the lips and partly emptied, the pressure being diminished, the air expanded and drove part of the contents in the face of the drinker. Another goblet was so contrived that no one could drink out of it unless he understood the art. The liquid was suspended in cavities, and discharged by admitting or excluding air through several secret openings.
The apparatus represented in the illustration ([Fig. 7]) represents an arrangement similar to that of the inexhaustible bottle of Robert-Houdin, but it is more ingenious. The problem proposed, as enunciated by Heron, the Greek engineer, who describes the apparatus, is as follows: “Being given a vessel, to pour into it, through the orifice, wines of several kinds, and to cause any kind that may be designated to flow out through the same orifice, so that, if different persons have poured in different wines, each person may take out in his turn all the wine that belongs to him.
“Let Α Β be a hermetically closed vessel whose neck is provided with a diaphragm, Ε Ζ, and which is divided into as many compartments as the kinds of wine that it is proposed to pour into it. Let us suppose, for example, Η Θ and Κ Α are diaphragms forming the three compartments, Μ, Ν, and Ξ, into which wine is to be poured. In the diaphragm, Ε Ζ, there are formed small apertures that correspond respectively to each of the compartments. Let Ο, Π, and Ρ be such apertures, into which are soldered small tubes, Π Σ, Ο Τ, and Ρ Υ, which project into the neck of the vessel. Around each of these tubes there are formed in the diaphragm small apertures like those of a sieve, through which the liquids may flow into the different compartments. When, therefore, it is desired to introduce one of the wines into the vessel, the vents, Σ, Τ, and Υ are stopped with the fingers, and the wine is poured into the neck, Φ, where it will remain without flowing into any of the compartments, because the air contained in the latter has no means of egress. But, if one of the said vents be opened, the air in the compartment corresponding thereto will flow out, and the wine will flow into such compartment through the apertures of the sieve. Then, closing this vent in order to open another, another quantity of wine will be introduced, and so on, whatever be the number of wines and that of the corresponding compartments of the vessel, Α Β.