On Architecture

18. Since it appears, then, that our architects in the old days, and a good many even in our own times, have been as great as those of the Greeks, and nevertheless only a few of them have published treatises, I resolved not to be silent, but to treat the different topics methodically in different books. Hence, since I have given an account of private houses in the sixth book, in this, which is the seventh in order, I shall treat of polished finishings and the methods of giving them both beauty and durability.

1. FIRST I shall begin with the concrete flooring, which is the most important of the polished finishings, observing that great pains and the utmost precaution must be taken to ensure its durability. If this concrete flooring is to be laid level with the ground, let the soil be tested to see whether it is everywhere solid, and if it is, level it off and upon it lay the broken stone with its bedding. But if the floor is either wholly or partly filling, it should be rammed down hard with great care. In case a wooden framework is used, however, we must see that no wall which does not reach up to the top of the house is constructed under the floor. Any wall which is there should preferably fall short, so as to leave the wooden planking above it an unsupported span. If a wall comes up solid, the unyielding nature of its solid structure must, when the joists begin to dry, or to sag and settle, lead to cracks in the floor on the right and left along the line of wall.