Chap. 14.]

Wheels for raising Water.

109

CHAPTER XIV.

Wheels for raising water—Machines described by Vitruvius—Tympanum—De La Faye’s improve-meil t— -Scoop Wheel—Chinese Noria —Roman do.—Egyptian do.—Noria with Pots—-Supposed origin ofToothed Wheels—Substitute for wheels and pinions—Persian Wheel: Common in Syria —Large onesat Hamath — Various modes of propelling the Noria by men and animals — Early employment of the lat-ter to raise water. Antiquity of the Noria —Supposed to be the ‘Wheel of Fortune’—An appropriateemblem of abundance in Egypt —Sphinx—Lions’ Heads—Vases—Cornucopia—Ancient emblems ofirrigation—Medea: Inventress of Vapor Baths—Ctesibius—Metallic and glass mirrors—Barbers .

Having examined such devices for raising water, as from their sim-plicity have been generally unnoticed in treatises on hydraulic machines,we proceed to others more complex; and first, to such as revolve roundthe centres from which they are suspended, and which have a continuousinstead of an alternating motion. Although differing in these respects andin their form, from the jantu or vibrating gutter and the swape, they will befound essentially the same; their change of figure being more apparent thanreal, and merely consequent on the new movement imparted to them. Asthese machines are obviously of later date than the preceding, it may per-haps be supposed, that the period of their introduction might be ascer-tained; but so it is, that with scarcely an exception, the time when, placewhere, and the persons by whom, they were invented, are absolutelyunknown.

Although allusions to machines for raising water are found in severalof their authors, it does not appear, that any general account or compre-hensive treatise of them, was ever written by the ancients. If such aWork was executed, it has perished in the general wreck of ancient re-cords. About the beginning of the Christian era, a Roman architect andengineer, published a treatise on those professions, in which he inserted ahrief description of some hydraulic engines. This is the only ancient workextant which treats professedly of them; and the whole that relates to themmight be included in two pages of this volume.

' The machines described by Vitruviüs , for it is to him we allude, arethe Tympanum, Noria , Chain of Pots, the Scretv, and the Machine ofCtesibius or Pump. He has not mentioned the jantu, swape, the cord andbücket, with the various modes of using the latter; probably, because heconsidered these too simple in their construction to be properly classedamong hydraulic machinery; he therefore passed by them, and modern au-thors have generally followed his example. Notwithstanding the omissionof these, there are circumstances which render it probable that his ac-count, brief as it is, includes all the principal machines that were used bythe nations of the old world, if we except China . He wrote at a period themost favorable for acquiring and transmitting to posterity, a perfect know-ledge of the mechanie arts of the ancient civilized nations ; for he flourishedduring the last scenes of the mighty drama, when Rome had become the ar-bitress of the world, and the enlightened nations of the east—their wealth,learning, arts and artisans, were prostrate at her feet; so that if we were tosuppose, absurd as it would be, that the previous intercourse of the Ro-mans with Asia Minor , Egypt , Carthage and G-reece, had not made them fa-miliär with the arts of those countries, nothing could have prevented themtrom possessing such knowledge when they became Roman provinces—■