Illustrated Companion to the Latin Dictionary/Cochlea

Illustrated Companion to the Latin Dictionary, and Greek Lexicon (Rich, 1849)

COCH'LEA (κοχλίας). Literally, a snail with a spiral shell; whence applied to several other objects partaking of a spiral form; as —

1. A worm and screw, as a mechanical power, employed in oil, wine, and clothes presses, precisely in the same manner, and formed upon similar principles to those now in daily use, as shown by the annexed wood-cut (Cochlea/1.1), representing a press for cloth, from a painting in the fuller's establishment (fullonica), at Pompeii. Vitruv. vi. 9. Plin. H. N. xviii. 74. Pallad. iv. 10. 10. Id. xi. 9. 1.

2. A contrivance for raising water, upon the principle of a screw, invented by Archimedes, and similar to the machine still to be seen in Germany, which goes by the name of the "water snail." It consisted of a long cylinder, with a hollow pipe coiled round it, like the thread of a screw; was placed in an oblique direction, with the lowest end in the water, and then made to turn round its own axis by the operation of cattle, or of a tread-wheel (tympanum); as it revolved, it gradually turned the water up through the coils of the pipe from the lowest to the topmost spiral, from which it ran out, as having nothing further to support it. (Vitruv. x. 6.) It is also mentioned by Strabo (xiii. 30. p. 561. ed. Siebenk.), as being used in Egypt, where it was worked by slaves, and employed for the purpose of irrigation; indeed, a pump of this description will only raise water to a moderate height.

3. A particular kind of doorway adapted for a bull-ring, aviary, and places of such description (Varro, R. R. iii. 5. 3.), where it was requisite that all who entered or went out should be enabled to do so with rapidity and security; in order that the animals might not escape with the opening of the door, while the person inside might retreat with safety upon any sudden emergency. Schneider (Index, R. R. Script. s. v. Cavea) considers this to have been a door raised and lowered after the manner of a portcullis, synonymous, therefore, with CATARACTA; but his proofs are far from conclusive, and the old interpretation of Gesner is more in unison with the other analogies of the word; viz. an apparatus like the one now commonly used in the foundling hospitals and convents of nuns in Italy for the purpose of introducing any thing into the interior, without opening a door, and which goes by the name of "the wheel," la ruota. It is constructed upon the same principle as a dark lantern, consisting of a cylindrical box, situated in the thickness of the main wall, and made to revolve round an upright axis which runs through its centre, and fixes it in its place. An aperture is left on one part of the circumference, through which, when turned to the street, the objects intended to be introduced are placed in the box, which is then pushed half round its axis, when the opening comes on the inside of the wall. It is obvious that such an apparatus would be particularly adapted for any of the purposes above mentioned to which the cochlea was put; and the name may have been obtained from the resemblance which such a contrivance bears to a snail within its shell, or to the spiral staircase (cochlis) within its case.

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  Cochlea/1.1