Aqueduct

A channel to convey water from one place to another. Aqueducts in military architecture are generally made to bring water from a spring or river to a fortre , etc.; they are likewise used to carry canals over low ground, and over brooks or small rivers; they are built with arches like a bridge, only not so wide, and are covered by an arch, to prevent dust or dirt from being thrown into the water,—there are also subterranean aqueducts, such as pipes of wood, lead, or iron.