BOOK FOUR

I have promised in this present volume to treat only of the ornaments and the various styles of buildings. For this reason, I will not speak now of how city and fortress gates should be positioned—with their flanks, embrasuresoriginal: "cannoniere"; openings in a wall for firing cannons, and other defensive requirements—leaving such a task to the military architect according to the sites and circumstances that may arise. However, once the gate of the city or fortress has been positioned, I will certainly describe the manner in which it should be adorned, in my opinion, by showing some figures. Every city gate requires a postern gateoriginal: "porta del soccorso"; literally "gate of relief," a secondary entrance used for reinforcements or safe exit, which others call a wicketoriginal: "ponticella"; literally "little bridge". But to maintain symmetry—which means a proportionate correspondence—it is necessary to create another false one on the opposite side.

The measurements of the gate are to be made so that the height is equal to the width of the opening plus half of that width i.e., a 1:1.5 ratio. The height should be divided into six parts: one part shall be the width of the pilaster-strip on the right and left sides. The face of the pilasters should be one-third the width of the gate, and their height should be five parts, including the bases and capitals. The height of the bases should be one-third of the pilaster’s width, as should the capitals, always observing the rules given in the first column. The height of the architrave, frieze, and cornice should be equal to the face of the pilaster, following the rules given for the first order. Between one pilaster and the other shall be the postern gate; its width should be equal to the face of the pilaster, and its height should be double its width. Its pilaster-strips must be one-third of the width of that gate. The elevation above the gate shall be at the discretion of the Architect, but we will demonstrate the proportions of the pedimentoriginal: "fastigio" or "frontespicio" in two ways within the Doric order.