AEOLIPILE

AEOLIPILE, Aeolipile, a hydraulic Instrument, consisting of a hollow metallic Ball, with a slender Neck or Pipe arising from the same; which being filled with Water, and thus exposed to the Fire, produces a vehement Blast of Wind. See Wind. This Instrument, Descartes and others have made use of, to account for the natural Cause and Generation of Wind. And hence its Name, Aeolipile, q.d. pila Aeoli, Aeolus's Ball, Aeolus being reputed the God of the Winds. See God.



Sometimes the Neck is made to screw into the Ball, which is the most commodious way, because then the Cavity may the more readily be filled with Water. If there be no Screw, it may be filled thus.—Heat the Ball red hot, and throw it into a Vessel of Water; the Water will run in at a small Hole, and fill about two thirds of the Cavity. If after this, the Aeolipile be laid on, or before, the Fire; so that the Water and Vessel become very much heated; the Water being rarified into a kind of momentary Air, will be forced out with very great Noise and Violence; there will be by Fits, and not with a constant and uniform Blast.

These Phenomena, the Reader will be easily enabled to solve, from what is shown under the Articles, Air, Water, Rarefaction, etc.

The Air or Vapor issuing out of the Aeolipile, is found sensibly hot near the Orifice; but at a farther distance, cold; like what we observe of our own Breath: The Cause of which is controverted.—The Corpuscularians account for it hence, that the Fire contained in the rarified Vapor, though sufficient to be felt near the Orifice, disengages itself in the Progress of the Stream; and becomes insensible before arriving at the Journey's End. See Fire.—The mechanical Philosophers, on the other hand, hold that the Vapor, at its Exit from the Ball, is endowed with that peculiar Species of circular Motion, which constitutes the Quality Heat; and that the further it recedes therefrom, the more is this Motion destroyed, by the Reaction of the contiguous Air; till the Heat at length becomes insensible. See Heat.

Chauvin suggests some further Uses of the Aeolipile.— 1°, He thinks it might be applied instead of Bellows to blow the Fire, where a very intense heat is required. 2°, If a Trumpet, Horn, or other sonorous Instrument were fitted to its Neck, it might be made to yield Music. 3°, If the Neck were turned perpendicularly upwards, and prolonged by a Tube or hollow Cylinder fitted to it, and a hollow Ball laid on the Orifice of the Tube; the Ball would be blown up, and kept fluctuating or playing up and down: As in the Stream of a Fountain. See Fountain. And, 5°, it might serve to scent, or perfume a Room, if filled with perfumed, instead of common Air.

AEOLIPILE