‹‹‹ Vitr. 7.3.8 | Table of Contents | Vitr. 7.3.10 ›››
9As a silver mirror, made from a thin plate, reflects the image confusedly and weakly, whilst from a thick solid plate it takes a high polish, and reflects the image brilliantly and strongly; so plastering, when thin in substance, not only cracks, but soon decays. On the contrary, that which is well covered with plaster and stucco, and closely laid on, when well polished, not only shines, but reflects to the spectators the images falling on it.
9Just 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 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.