On Architecture

Vitruvius Pollio

Vitruvius Pollio, creator; Morgan, M. H. (Morris Hicky), 1859-1910, translator

9. Just as a silver mirror that is formed of a thin plate reflects indistinctly and with a feeble light, while one that is substantially made can take on a very high polish, and reflects a brilliant and distinct image when one looks therein, so it is with stucco. When the stuff of which it is formed is thin, it not only cracks but also soon fades; when, however, it has a solid foundation of sand mortar

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and of marble, thickly and compactly applied, it is not only brilliant after being subjected to repeated polishings, but also reflects from its surface a clear image of the beholder.

10. The Greek stucco-workers not only employ these methods to make their works durable, but also construct a mortar trough, mix the lime and sand in it, bring on a gang of men, and beat the stuff with wooden beetles, and do not use it until it has been thus vigorously worked. Hence, some cut slabs out of old walls and use them as panels, and the stucco of such panels and “reflectors” has projecting bevelled edges all round it.

11. But if stucco has to be made on “wattle and daub,” where there must be cracks at the uprights and cross-sticks, because they must take in moisture when they are daubed with the mud, and cause cracks in the stucco when they dry and shrink, the following method will prevent this from happening. After the whole wall has been smeared with the mud, nail rows of reeds to it by means of “fly-nails,” then spread on the mud a second time, and, if the first rows have been nailed with the shafts transverse, nail on a second set with the shafts vertical, and then, as above described, spread on the sand mortar, the marble, and the whole mass of stucco. Thus, the double series of reeds with their shafts crossing on the walls will prevent any chipping or cracking from taking place.

1. HAVING 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

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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.

2. But 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.