4Having spoken of the method by which stucco work should be done in dry situations, I shall next explain how the polished finish is to be accomplished in places that are damp, in such a way that it can last without defects. First, in apartments which are level with the ground, apply a rendering coat of mortar, mixed with burnt brick instead of sand, to a height of about three feet above the floor, and then lay on the stucco so that those portions of it may not be injured by the dampness. But if a wall is in a state of dampness all over, construct a second thin wall a little way from it on the inside, at a distance suited to circumstances, and in the space between these two walls run a channel, at a lower level than that of the apartment, with vents to the open air. Similarly, when the wall is brought up to the top, leave airholes there. For if the moisture has no means of getting out by vents at the bottom and at the top, it will not fail to spread all over the new wall. This done, apply a rendering coat of mortar made with burnt brick to this wall, spread on the layer of stucco, and polish it.
2But if there is not room enough for the construction of a wall, make channels with their vents extending to the open air. Then lay two-foot tiles resting on the margin of the channel on one side, and on the other side construct a foundation of pillars for them, made of eight-inch bricks, on top of each of which the edges of two tiles may be supported, each pillar being not more than a hand’s breadth distant from the wall. Then, above, set hooked tiles fastened to the wall from bottom to top, carefully covering the inner sides of them with pitch so that they will reject moisture. Both at the bottom and at the top above the vaulting they should have airholes.
3Then, whitewash them with lime and water so that they will not reject the rendering coat of burnt brick. For, as they are dry from the loss of water burnt out in the kiln, they can neither take nor hold the rendering coat unless lime has been applied beneath it to stick the two substances together, and make them unite. After spreading the rendering coat upon this, apply layers of burnt brick mortar instead of sand mortar, and finish up all the rest in the manner described above for stucco work.
4The decorations of the polished surfaces of the walls ought to be treated with due regard to propriety, so as to be adapted to their situations, and not out of keeping with differences in kind. In winter dining rooms, neither paintings on grand subjects nor delicacy of decoration in the cornice work of the vaultings is a serviceable kind of design, because they are spoiled by the smoke from the fire and the constant soot from the lamps. In these rooms there should be panels above the dadoes, worked in black, and polished, with yellow ochre or vermilion blocks interposed between them. After the vaulting has been treated in the flat style, and polished, the Greek method of making floors for use in winter dining rooms may not be unworthy of one’s notice, as being very inexpensive and yet serviceable.
5An excavation is made below the level of the dining room to a depth of about two feet, and, after the ground has been rammed down, the mass of broken stones or the pounded burnt brick is spread on, at such an inclination that it can find vents in the drain. Next, having filled in with charcoal compactly trodden down, a mortar mixed of gravel, lime, and ashes is spread on to a depth of half a foot. The surface having been made true to rule and level, and smoothed off with whetstone, gives the look of a black pavement. Hence, at their dinner parties, whatever is poured out of the cups, or spirted from the mouth, no sooner falls than it dries up, and the servants who wait there do not catch cold from that kind of floor, although they may go barefoot.