Architecture depends on Order, Arrangement, Eurythmy, Symmetry , Propriety , and Economy.

For we must not build temples according to the same rules to all gods alike, since the performance of the sacred rites varies with the various gods.

Trees which grow in places facing the course of the sun are not of porous fiber but are solid, being drained by the dryness... The trees in sunny neighborhoods, therefore, being solidified by the compact texture of their fiber, and not being porous from moisture, are very useful, so far as durability goes, when they are hewn into timber. The lowland firs, being conveyed from sunny places, are better than those highland firs, which are brought here from shady places.

Fresh pitsand, however, in spite of all its excellence in concrete structures, is not equally useful in stucco, the richness of which, when the lime and straw are mixed with such sand, will cause it to crack as it dries on account of the great strength of the mixture. But river sand, though useless in "signinum" on account of its thinness, becomes perfectly solid in stucco when thoroughly worked by means of polishing instruments.

The third order, called Corinthian, is an imitation of the slenderness of a maiden; for the outlines and limbs of maidens, being more slender on account of their tender years, admit of prettier effects in the way of adornment.

Wind is a floating wave of air, whose undulation continually varies.

The construction of temples of the Ionic order to Juno, Diana, Father Bacchus, and the other gods of that kind, will be in keeping with the middle position which they hold; for the building of such will be an appropriate combination of the severity of the Doric and the delicacy of the Corinthian.