Part 8
When a fire is kindled on an altar, figures placed near shall offer libations, and a serpent hiss. Let there be a hollow pedestal, A B (fig. 60), on which is an altar, C, containing within it a tube, D E, which descends from the hearth of the altar to the pedestal, and then branches off into three tubes, E F leading to the mouth of the serpent; E G H to a wine vessel K L, (the bottom of which must be higher than the figure M,) and fastened to the lid of K L cross-bar fashion; while the other tube E N X, in like manner, extends into another wine vessel O P, also terminating in a cross-head. Both these tubes must be soldered into the bottoms of the vessels, and in each wine vessel there must be a bent siphon, R S, and T U, one extremity of each being immersed in the wine, and the other, (from which extend the hand of the figure which is to pour the libation,) passing, air-tight, through the side of the wine vessel. When the fire is about to be kindled, pour first a little water into the tubes, that they may not be burst by the dry heat, and close up everything that no air may pass through. The hot air, becoming mixed with the water, will ascend along the tubes to the cross-heads, and through them it will exert pressure on the wine, and carry it to the bent siphons R S and T U. The wine flowing through the hands of the figures produces a libation as long as a fire is burning on the altar. The other tube, conveying the hot air to the mouth of the serpent, will cause the serpent to hiss.
61. _Water flowing from a Siphon ceases on surrounding the End of its longer Side with Water._
[Illustration: Diagram of apparatus as described in text]
Let there be an air-tight vessel provided with an open spout, and by its side a thyrsus under which is a cup full of water: if the cup is removed, as long as it is withdrawn, a small stream shall flow from the mouth; but when the cup is pushed back, the spout shall run no longer. Let A B (fig. 61), be the vessel described, having its neck closed by the partition C D; from C D, and fitted air-tight in it, a tube, E F, extends, about which lies another tube, K L, forming an inclosed diabetes. With K L another tube, M N, communicates, of which the mouth M is open, while the outer leg is placed in a cup, O X, into which water has been poured until it is full; it is clear that so much of the leg of the siphon as is in the cup will be filled at the same time. Into the neck of the vessel A B a little water must be poured, just enough to close all entrance for the air; and, when A B is full, the spout P, though open, will not run, since the air has no means of entrance, because of the water poured into the neck. But if the cup is drawn slightly downwards, some portion of the leg of the siphon which is in the cup must be emptied, and into the part emptied the contiguous air will be drawn: this air will attract some of the water which was poured into the neck, so that the water shall rise above the mouth F; and hence, the air having found an entrance, the spout P will run until the cup O X is pushed up again, causing the water to return to its old position and to close the passage for the air so that the spout will cease to flow. This will happen as often as the cup is withdrawn and applied: it is necessary however that the cup be not wholly drawn away, that the siphon leg may not be wholly emptied. Let the tube M N be fashioned like a thyrsus, R N being its shaft: thus the spectacle will be properly arranged.
62. _A Vessel which emits a Sound when a Liquor is poured from it._
[Illustration: Diagram of apparatus as described in text]
The construction of a flagon which utters a sound when liquid is forced from it. Take a flagon (fig. 62), such as is about to be described, the neck of which is closed by the plate A B, and the mouth by C D; and through both these partitions, fitting into them air-tight, let a tube, E F, be inserted. G H is the handle of the flagon, and K L a tube placed in the opposite side of the neck, fitting closely into the partition A B and far enough distant from C D to allow of the passage of water: in C D let there be a small pipe M such as will utter sound. The flagon may be filled through the tube E F, the air passing out through the tube K L and the pipe M; and if we take the handle of the flagon and incline it so as to pour out the contents, water will flow out of the vessel through the tube E F, and into the neck B C through K L: the air contained in the neck being forced out through M gives forth a sound. There should be another hole in A B through which air may pass again when the vessel is righted.
63. _A Water-Clock, made to govern the quantities of Liquid flowing from a Vessel._
[Illustration: Diagram of apparatus as described in text]
A vessel containing wine, and provided with an open spout, stands upon a pedestal: it is required by shifting a weight to cause the spout to pour forth a given quantity,—sometimes, for instance, a half cotyle (¼ pint), sometimes a cotyle (½ pint), and, in short, whatever quantity we please. A B (fig. 63), is the vessel into which wine is to be poured: near the bottom is a spout, D: the neck is closed by the partition E F, and through E F is inserted a tube, G H, reaching nearly to the bottom of the vessel, but so as to allow of the passage of water. K L M N is the pedestal on which the vessel stands, and O X another tube reaching within a little of the partition and extending into the pedestal, in which water is placed so as to cover the orifice O, of the tube. Fix a rod, P R, one half within, and the other without, the pedestal, moving like the beam of a lever about the point S; and from the extremity P of the rod suspend a water-clock, T, having a hole in the bottom. The spout D having been first closed, the vessel should be filled through the tube G H before water is poured into the pedestal, that the air may escape through the tube X O: then pour water into the pedestal, through a hole, until the orifice O is closed, and set the spout D free. It is evident that the wine will not flow, as there is no opening through which air can be introduced: but if we depress the extremity R of the rod, a portion of the water-clock will be raised from the water, and, the vent O being uncovered, the spout D will run until the water suspended in the water-clock has flowed back and closed the vent O. If, when the water-clock is filled again, we depress the extremity R still further, the liquid suspended in the water-clock will take a longer time to flow out, and there will be a longer discharge from D: and if the water-clock be entirely raised above the water, the discharge will last considerably longer. To avoid the necessity of depressing the extremity R of the rod with the hand, take a weight Q, sliding along the outer portion of the rod, R W, and able, if placed at R, to lift the whole water-clock; if at a distance from R, some smaller portion of it. Then, having obtained by trial the quantities which we wish to flow from D, we must make notches in the rod R W and register the quantities; so that, when we wish a given quantity to flow out, we have only to bring the weight to the corresponding notch and leave the discharge to take place.
64. _A Drinking-Horn from which a Mixture of Wine and Water, or pure Water may be made to flow alternately or together, at pleasure._
[Illustration: Diagram of apparatus as described in text]
The construction of a drinking-horn from which at first a mixture shall flow; when we please, on pouring in water, water alone, and then again a mixture. Let A B (fig. 64), be a drinking-horn, its neck closed by the plate C D, through which is inserted a tube, E F, leading to the orifice F, and having a hole, G, bored in it within the vessel: in the vessel just under the partition make a vent H. Now, if we close the orifice F and pour in the mixture, it will pass into the body of the vessel through the hole G; and if we set F free, the mixture will flow through it, the air entering by the vent H. Again, if we close H and pour in pure water, the mixture will no longer flow as the air has no means of entrance, but pure water; and, when H is set free, both will flow, the water and the mixture, or rather a mixture which is produced from the two united.
65. _A Vessel from which Wine or Water may be made to flow separately or mixed._
[Illustration: Diagram of apparatus as described in text]
If water is poured into a vessel standing upon a pedestal and provided with a spout somewhat above its bottom, at one time pure water flows out, at another a mixture of wine and water, and then unmixed wine alone. Let A B (fig. 65), be the vessel, standing upon a pedestal and provided with the spout C D, of which the orifice C is above the bottom of the vessel. Close the neck of the vessel with the partition E F, and through E F insert the tube G H, projecting slightly above the partition and extending to the bottom of the vessel except that a space is left sufficient for the passage of water. In the body of the vessel, and projecting without it, let there be another tube K L, under which a vessel of unmixed wine, K M, is to be placed: in the partition E F pierce a very fine hole N. If, when these arrangements are complete, we pour water into the vessel through the neck, the liquid lying round the projection of the tube will remain in the neck; but all above this will be carried into the body of the vessel, and when it has reached the orifice C of the spout, there will be a discharge of pure water. When a stream has begun to issue from the spout, the unmixed wine in the vessel K M will be drawn up at the same time, on the principle of the siphon, and a mixture will be discharged; and when the water is exhausted, the pure wine will flow by itself, except indeed that the water about the partition E F will be attracted at the same time. When the small quantity of water on E F has all run through N, the air will enter and break the continuity and there will be no further discharge.
66. _Wine discharged into a Cup in any required quantity._
[Illustration: Diagram of apparatus as described in text]
Let there be a vessel filled with wine and provided with a spout under which a drinking cup is placed: wine shall run into the cup in any required quantity. Let A B (fig. 66), be the vessel containing wine, and C D the spout, the upper surface of which at the extremity C is so smooth that, when a valve in the form of a kettle-drum E F is placed upon it, water is excluded. On the handle of the vessel fix the vertical rod G H, on which, as on a fulcrum, another rod K L vibrates: again place another rod, M N, under the pedestal, moving about the point X, and attach two more rods K O, L P, moving on pivots in such a way that, if the extremity M of the bar be depressed, the valve E F is raised, and the spout is opened and sends out a stream, but is closed again when M is suffered to return. Let the bar M N support the drinking cup R, into which we wish to receive the given quantity of liquid: the cup must be placed beneath the spout. Take a weight, S, capable, by means of a ring, of being shifted along the projection M O of the rod: and when S has been brought towards M, the spout will be opened and send its stream into the cup, but as the cup grows heavy the weight will be raised again and the spout closed. That the wine may flow out in the required quantity, place in the cup any measure of liquid, for instance, a cotyle, and, receiving what falls from the spout in another vessel, shift the weight along the bar to the first point at which the discharge from the spout ceases: make a mark on the bar at this point and register one cotyle. We must proceed in the same manner for a half-cotyle, and two cotylæ, and so on for other measures as far as we please; and thus we shall have marks for the different quantities, signifying the points to which the weight must be brought in order that they may be discharged. Instead of the valve E F, an air-tight vessel may encircle the spout, so that, as long as the liquid is kept away by the air within, there will be no discharge through the spout.
67. _A Goblet into which as much Wine flows as is taken out._
[Illustration: Diagram of apparatus as described in text]
Let there be a vessel containing wine and provided with a spout, underneath which a goblet is placed: whatever quantity of wine is taken from the goblet, as much shall flow into it from the spout. Let A B (fig. 67), be the vessel of wine, and C D the spout, to which are attached the valve E F, and the rods G H, K L, K O, L M as before; and beneath the spout place the cup P. To the rod K O fix a small basin R contained in the vessel S T, and let a tube, U Q, connect the vessels S T and P. When these arrangements are complete, if the vessels S T and P are empty, the basin R will fall to the bottom of S T, and open the spout C D. A stream will flow from C D into both the vessels S T and P, so that the basin will rise and shut the spout again, until we remove more liquid from the goblet. This result will happen as often as we remove liquid from P.
68. _A Shrine over which a Bird may be made to revolve and sing by Worshippers turning a Wheel._
[Illustration: Diagram of apparatus as described in text]
The construction of a shrine provided with a revolving wheel of bronze, termed a purifier, which worshippers are accustomed to turn round as they enter. Let it be required that, if the wheel is turned, the note of the black-cap shall be produced, and the bird, standing on the top of the shrine, turn round as well; while, if the wheel is turned [in the opposite direction], the black-cap neither sings nor revolves. Let A B C D (fig. 68), be the shrine and E F an axis extending across it, capable of revolving freely, to which the wheel H K, which is to be turned round, is attached. Let two other wheels be attached to the axis, in the interior of the shrine, L and M, of which L has a pulley, and M is a wheel with rays. Round the pulley a cord is wound, from the extremity of which is suspended a vessel N, shaped like a conical oven, and provided with a tube X O, terminating in a small pipe which produces the note of a black-cap: under the conical vessel N must be placed a vessel of water. From the top of the shrine let fall a small axis S T capable of revolving freely: at the extremity S let a black-cap be placed, and at T a wheel with rays, the rays of which are implicated with, or take into, the rays of the wheel M. It will be found that, when the wheel H K is made to revolve, the cord is wound round the pulley and raises the conical vessel N; but, if the wheel is let go, N descends by its own weight into the water and produces the sound by the expulsion of the air. The black-cap turns round at the same time owing to the revolution of the wheels.
69. _A Siphon fixed in a Vessel from which the Discharge shall cease at will._
[Illustration: Diagram of apparatus as described in text]
There are certain siphons which, when placed in vessels, flow until the vessels are emptied, or the surface of the water has sunk to the level of the outer orifice of the siphon. Let it be required that the discharge shall suddenly cease whenever we wish. A B (fig. 69), is a vessel containing a siphon, C D E, the inner leg of which is bent upwards as at C F G. Let a vertical rod H K be fixed, on which another, L M, works as a lever-beam: from L M extends another rod, M N, moving on a pivot, and provided at the extremity N with a vessel large enough to encircle the bent portion of the siphon F G. On the rod L M suspend a weight at L, so that the encircling vessel is raised above the upward bend of the siphon, and the siphon flows. When we wish the discharge to cease, we have only to remove the weight at L, and the vessel at N will descend and encircle the bend G C, so that the siphon will cease to flow. If it is desired that the stream should continue, we must again suspend the weight.
70. _Figures made to dance by Fire on an Altar._
[Illustration: Diagram of apparatus as described in text]
When a fire is kindled on an altar, figures shall be seen to dance: for the altars must be transparent, either of glass or horn. Through the hearth of the altar (fig. 70), a tube is let down turning on a pivot towards the base of the altar, and, above, on a small pipe which is attached to the hearth. Communicating with, and attached to, this tube are smaller tubes lying at right angles to each other, and bent at the extremities in opposite directions. A wheel or platform on which the dancing figures stand, is also fastened to the tube. When the sacrifice is kindled, the air, growing hot, will pass through the pipe into the tube, and be forced out of this into the smaller tubes; when, meeting with resistance from the sides of the altar, it will cause the tube and the dancing figures to revolve.
71. _A Lamp in which the Oil can be raised by Water contained within its Stand._
[Illustration: Diagram of apparatus as described in text]
The construction of a lamp-stand, such that, if a lamp is placed upon it, whenever the oil fails, a supply shall be poured into it from the handle to the amount required, though no vessel is placed upon the lamp from which the oil can flow into it. Let the lamp-stand be constructed with a triangular pedestal, like a pyramid, A B C D (fig. 71), hollow and provided with a partition E F. Let G H, which must also be hollow, be the shaft of the lamp-stand, and above this shaft place a hollow cup, K L, capable of containing a considerable quantity of oil. From the partition E F, and fitting closely into it, a tube, M N, must extend upwards, leaving a passage for the air between its extremity and the covering of the cup, K L, on which the lamp is placed. Through the plate K L insert another small tube X Q, a passage being left for water between it and the bottom of the cup: the tube X Q must project a little above the plate K L, and into the projecting part another pipe P is tightly fitted, closed at its upper extremity, and passing through the bottom of the lamp so as to be included within it, that there may be no projection outside. To P solder another pipe, extremely fine, communicating with it, and reaching to the extremity of the handle, so that its stream will be carried into the body of the lamp; this pipe must have an orifice like the others. Under the partition E F let a tap be soldered leading into the chamber C D E F, so that, when it is opened, the water in the chamber A B E F will pass into C D E F. In the plate A B let a fine hole be perforated through which A B E F may be filled with water; the [air] contained in it will pass out through the same hole. We now remove the lamp and fill the cup with oil through the pipe X Q, the air escaping through M N, and again through an open cock in the bottom C D, when any water in C D E F has first flowed out. The lamp having been placed on the top by means of the sliding tube P, when it is required to pour in oil, we must open the tap in the plate E F, and the water in the chamber A B E F passing into C D E F, the air in C D E F will reach the cup through the tube M N, and force out the oil contained in it: the oil will pass into the lamp through the tube X Q and the pipe attached to it. When we wish the oil to stop running, we must shut the cock and the discharge will cease. This process can be repeated whenever it is necessary.
72. _A Lamp in which the Oil is raised by blowing Air into it._
[Illustration: Diagram of apparatus as described in text]