added to them. This attracts all the little pieces of gold and makes them combine widi itself. When the water has been poured off, the residue is emptied into a cloth and then squeezed in the hands; the quicksilver, because it is a liquid, escapes through the loose texture of the cloth; the gold, brought together by the squeezing, is found inside in a pure state.473
Pliny474 also describes the practical uses of quicksilver, but he adds little to what Vitruvius says. The Leyden Papyrus X contains recipes for gilding with the aid of mercury, for preparing gold amalgams for lettering in gold, for "silvering" copper objects with mercury, and for making various simple and complex amalgams of base metals in imitation of silver.
fcft. It is made whtn cinnabar mixed with vinegar is ground in a copper vessel with a pestle made of copper. A lacuna in the manuscripts and Aldus shows that a word is missing before τριφθχ). This must be κοννάβαρι, which can be supplied from Pliny,475 who seems to be quoting from Theophrastus. The chemical facts also require it.
This was no mere mechanical method for the liberation of the metal from a natural mixture of mercury and cinnabar, but it was a true chemical process that depended upon the displacement of the mercury from the cinnabar by the more active metal placed in contact with it. Lenz4Te doubted that cinnabar would be decomposed by the process here described by Theophrastus, and Bliimner477 apparently accepts this opinion, but Bailey478 has demonstrated by an experiment that cinnabar can be decomposed when it is subjected to this treatment. This experiment was performed by grinding cinnabar with copper turnings and vinegar. Though the reaction was found to proceed very slowly when the mixture was cold, it took place readily enough when it was warmed, and the products were copper sulfide and mercury. However, the liberated mercury soon united with some of the unchanged copper to form an amalgam of copper and mercury.
*«VII, 8, 4. 47* XXXIII, 99, 125. *" XXXIII, 123.
476 Mineralogie der alien Griechen und Romcr, p. 26.
*TT Technologic und Terminologie der Gewerbe und Kiinste bet Griechen und Romern, Vol. IV, p. 98.
478 The Elder Pliny's Chapters on Chemical Subjects, Part I, p. 223.
