On Architecture

3. Then, upon this lay the bedding, composed of stones not smaller than can fill the hand. After the bedding is laid, mix the

4. After it is laid and set at the proper inclination, let it be rubbed down so that, if it consists of cut slips, the lozenges, or triangles, or squares, or hexagons may not stick up at different levels, but be all jointed together on the same plane with one another; if it is laid in cubes, so that all the edges may be level; for the rubbing down will not be properly finished unless all the edges are on the same level plane. The herring-bone pattern, made of Tibur burnt brick, must also be carefully finished, so as to be without gaps or ridges sticking up, but all flat and rubbed down to rule. When the rubbing down is completely finished by means of the smoothing and polishing processes, sift powdered marble on top, and lay on a coating of lime and sand.

5. In the open air, specially adapted kinds of floors must be made, because their framework, swelling with dampness, or shrinking from dryness, or sagging and settling, injures the floors by these changes; besides, the frost and rime will not let them go unhurt. Hence, if necessity drives, we must proceed as follows in order to make them as free from defects as possible. After finishing the plank flooring, lay a second plank flooring over it at right angles, and nail it down so as to give double protection to the framework. Then, mix with new broken stone one third the quantity of pounded tile, and let lime be added to the mixture in the mortar trough in the proportion of two parts to five.

6. Having made the bedding, lay on this mixture of broken

7. If, however, it seems needful to use still greater care, lay, two-foot tiles, jointed together in a bed of mortar, over the broken stone, with little channels of one finger's breadth cut in the faces of all the joints. Connect these channels and fill them with a mixture of lime and oil; then, rub the joints hard and make compact. Thus, the lime sticking in the channels will harden and solidify into a mass, and so prevent water or anything else from penetrating through the joints. After this layer is finished, spread the nucleus upon it, and work it down by beating it with rods. Upon this lay the floor, at the inclination above described, either of large cubes or burnt brick in herring-bone pattern, and floors thus constructed will not soon be spoiled.

1. LEAVING the subject of floors, we must next treat of stucco work. This will be all right if the best lime, taken in lumps, is slaked a good while before it is to be used, so that if any lump has not been burned long enough in the kiln, it will be forced to throw off its heat during the long course of slaking in the water, and will thus be thoroughly burned to the same consistency. When it is taken not thoroughly slaked but fresh, it has little crude bits concealed in it, and so, when applied, it blisters. When such bits complete their slaking after they are on the building, they break up and spoil the smooth polish of the stucco.

2. But when the proper attention has been paid to the slaking, and greater pains have thus been employed in the preparation for the work, take a hoe, and apply it to the slaked lime in the mortar bed just as you hew wood. If it sticks to the hoe in bits, the lime is not yet tempered; and when the iron is drawn out dry and clean, it will show that the lime is weak and thirsty; but when the lime is rich and properly slaked, it will stick to the tool like glue, proving that it is completely tempered. Then get the scaffolding ready, and proceed to construct the vaultings in the rooms, unless they are to be decorated with flat coffered ceilings.