In the tract between the Tigris and the Upper Zab, which is the only part of Assyria that has been minutely examined, are distinct remains of at least one Assyrian canal, wherein much ingenuity and hydraulic skill is exhibited, the work being carried through the more elevated ground by tunnelling, and the canal led for eight miles contrary to the natural course of every stream in the district.

Sluices and dams, cut sometimes in the solid rock, regulated the supply of the fluid at different seasons, and enabled the natives to make the most economical application of the great fertilizer.

The use of the hand-swipe was also certainly known, since it is mentioned by Herodotus, and even represented upon the sculptures.

[PLATE XXV., Fig.

1.] Very probably other more elaborate machines were likewise employed, unless the general prevalency of canals superseded their necessity.