ABSTRACT
This chapter concerns the work's position on the technology and history of elevated aqueducts, which is beset by questions about the aqueducts themselves as well as the aqueduct text. The elevated aqueducts may be found in Mesopotamia. The aqueducts were built by contractors and their engineers. These men must have had experience and interest regarding the choice of elevated arcades, surface channels, near-surface or deep-cut tunnels, or possibly inverted siphons. Vitruvius fully acknowledged earlier aqueduct writings: he mentions more than are known from the surviving literature. In the late 1700s, renewed classical studies made it clear that Vitruvius had sometimes been overestimated, and that his significance for Graeco-Roman art and science must be evaluated realistically. In Rome itself, the Porta Maggiore is still intact and it is possible to visualize how the aqueducts built at different times converged and extended over or near or under its arches.
