Altars should face the east, and should always be placed on a lower level than are the statues in the temples, so that those who are praying and sacrificing may look upwards towards the divinity. They are of different heights, being each regulated so as to be appropriate to its own god. Their heights are to be adjusted thus: for Jupiter and all the celestials, let them be constructed as high as possible; for Vesta and Mother Earth, let them be built low. In accordance with these rules will altars be adjusted when one is preparing his plans.

Having described the arrangements of temples in this book, in the following we shall give an exposition of the construction of public buildings.