Note 14 — BOOK VI.

[Pg 174][14] Vitruvius (X., 9). "But if the water is to be supplied to still higher places, a double chain of iron is made to revolve on the axis of the wheel, long enough to reach to the lower level. This is furnished with brazen buckets, each holding about a congius. Then by turning the wheel, the chain also turns upon the axis and brings the buckets to the top thereof, on passing which they are inverted and pour into the conduits the water they have raised."