Instead of erecting buildings on the surface of the ground, the people who formed those awful wonders of antiquity began their operations by cutting away the foundation of the rock, to obtain room below, without endangering the superstructure; and thus, by degrees, the Indian architecture seems to have grown to the most beautiful forms, from the rudest excavations. The use which I wish to make of this digression, is, to explain the manner of passing the valley by artificial means where the road does not require a common bridge, but rather a viaduct, to ornament the dam or mound of earth thrown across the valley; and, as this must necessarily cause some obstruction to the water, I think it might be made subservient to the other object in view-that of raising the water to a higher level, instead of digging a deeper channel; thus producing a continued surface of water in appearance, though, in fact, the levels may be very different. There being, at present, no architectural form adapted to this purpose, I have ventured to suggest a hint for such a structure as may support the road, and raise the level of the water, rather calling it a viaduct than a bridge [see fig. 222].
