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Chap. 14.]
diameter. According to Staunton, some raise over three hundred tons ofwater in twenty-f’our hours. A wriler in the Chinese Repository, men-tions öthers which raise a hundred and fifty tons to the height of fortyfeet, during the same time. They combine strength and lightness in a re-markable degree. a
The mode of constructing and moving the noria by the Romans, isthus described by Yitruvius : “ When water is to be raised higher, than
by the tympanum, a wheel is made round an axis, of such a magnitude,as the height to which the water is to be raised requires. Around the ex-tremity of the side of the wheel, square buckets cemented with pitch andwax are fixed ; so that when the wheel is turned by the walking of men,the filled buckets being raised to the top, and turning again toward thebottom, discharge of themselves what they have brought into the reser-voir.” B. x, Cap. 9. Newton’s Trans. As the drawings made by Vi-truvius himself, and annexed to his work are all lost, his translators donot always agree respecting the precise form of the machines describedby him. Newton has figured the noria as a large drum, to one side of whichsquare boxes or buckets are secured. These buckets are closed on allsides, with the exception of an opening to admit and discharge the water.Perault has placed them on the paddles or floats of an undershot wheel,like Barbaro, except that the latter makes the bottom of the boxes orbuckets serve at the same time as paddles to receive the impulse of thestream. Rivius, in his German Translation, (Nuremburgh 1548,) has givenone figure resembling an overshot wheel with the motion reversed, a formin which it is still sometimes made; in another, it is similar to the noriaof Egypt at the present day, a modification of it, probably of great antiquity.
Instead of pots or other vessels secured to the arms by ligatures, orbuckets attached to the sides of a wheel, as described by Yitruvius, theperiphery of the wheel itself is made hollow, and is divided into a numberof cells, or compartments, which answer the same purpose as separate ves-
a Van Braam’s Journal, i, 172. Ellis’s Journal of Amherst’s Embassy, 280. ChineseRepository, iii, 125.
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