B O O K F O U R

This style of segmental-arched portal original: "porta a remenato"—a shallow arch forming a segment of a circle rather than a full semi-circle, which comprises the sixth part of a circle, is a very sturdy structure; nevertheless, the voussoirs voussoirs: the wedge-shaped stones, called "cunei" in the original, that make up the arch cannot be integrated with other stone bindings, but must remain separate without being joined to other continuous courses of masonry. For this reason, if one wishes to build such a work, it would be well suited to a wall made of brickwork original: "opera lateritia"—the ancient Roman style of building with thin, flat bricks. Regarding its proportions, I shall not elaborate further, as it will be a simple task to find its measurements using a compass the author assumes the reader will use a divider or compass to take measurements directly from the printed illustration to scale them to a real building. However, as for the niches original: "nicchi" placed at the sides to fill the empty space, the Architect may position them at his own discretion in the places that best suit his purpose. They may serve not only as niches but also as windows. If they are intended to hold statues, it is always advisable for the height to exceed the double proportion meaning the height should be more than twice the width to provide enough vertical space, so that a standing statue placed within corresponds more harmoniously; such matters are always left to the judgment of the Architect.