1I shall begin with pavements, which are the principal of the finishings, and should be executed with the greatest care and attention to their solidity. If the pavement be made on the ground itself, the soil must be examined, to ascertain that it is solid throughout, then over it is to be spread and levelled a layer of rubbish. But if the whole or any part of the earth be loose, it is to be made solid with a rammer. In timber floors care must be taken that no wall be built under them, so as to touch the under side of the floors; but that a space be rather left between them and the floors. For if they be made solid, the timber of the floors drying and settling, whilst the wall remains in its place, will cause fissures in the pavement to the right and left.
2Care must also be taken that holm timber be not used with oak; for as soon as oak becomes damp, it warps, and causes cracks in the pavement. If, however, holm is not to be had, and on that account it be absolutely necessary to use oak, it should be cut very thin, by which means its power will be diminished, and it will be more easily fastened with the nails. Then through the edges of the boards two nails are to be driven into every joist, so that no part of the edges may warp. I do not mention the chestnut, beech, or the farnus, because neither of them are durable. The floor being prepared, fern, if at hand, and if not, straw, is to be spread over it, so that the timber may not be injured by the lime.
3On this is placed a layer of stones, each of which is not to be less than will fill a man’s hand. These being spread, the pavement is laid thereon. If the rubbish be new, let three parts of it be mixed with one of lime; but if from old materials, the proportion is five parts to two of lime. It is then laid on, and brought to a solid consistence with wooden beaters and the repeated blows of a number of men, till its thickness is about three quarters of a foot. Over this is spread the upper layer, composed of three parts of potsherds to one of lime, of a thickness not less than six inches. Over the upper layer the pavement is laid to rule and level, whether composed of slabs or of tesseræ.
4When laid with their proper inclination, they are to be rubbed off, so that, if in slabs, there may be no rising edges of the ovals, triangles, squares, or hexagons, but that the union of the different joints may be perfectly smooth. If the pavement be composed of tesseræ, the edges of them should be completely smoothed off, or the work cannot be said to be well finished. So, also, the Tiburtine tiles, peaked at the points, should be laid with care, that there may be neither hollows on them, nor ridges, but that they be flat, and rubbed to a regular surface. After the rubbing and polishing, marble dust is strewed over it, and over that a coat of lime and sand.
5Pavements are, however, more fit to be used in the open air, inasmuch as timbers expanding in a moist atmosphere, and contracting in a dry one, or sagging in the middle, cause defects in the pavement by their settlements. Moreover, frosts and ice soon ruin them. But as they are sometimes required, they must be made as follows. Over the first flooring, boards, others crossing them, must be laid, fastened with nails; thus giving a double covering to the beams. The pavement is composed of two parts of fresh rubbish, one of potsherds, and two of lime.
6After the first layer of rubbish on the floor, this composition is spread over it, and pounded into a mass not less than a foot thick. The upper layer being then spread, as above directed, the pavement, consisting of tesseræ, each about two inches thick, is laid, with an inclination of two inches to ten feet: if thus executed, and afterwards properly rubbed, it will not be liable to defects. In order that the mortar at the joints may not suffer by the frost, at the approach of winter every year it should be saturated with the dregs of oil, which will prevent the frost affecting it.
7If extraordinary care be required, the pavement is covered with tiles two feet square, properly jointed, having small channels, of the size of an inch, cut on each edge. These are filled with lime tempered with oil, the edges being rubbed and pressed together. Thus the lime in the channels growing hard, suffers neither water nor any thing else to penetrate. After this preparation the upper layer is spread and beaten with sticks. Over this either large tesseræ or angle tiles are laid at the inclination above directed, and work so executed will not be easily injured.