Page:Popular Science Monthly Volume 45.djvu/127

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
ANCIENT AND MEDIÆVAL CHEMISTRY.
115

because they point to the beginning of chemistry by moist processes. They figured in Pliny and the ancient authors, to the same purposes. The liquids are always natural ones or the results of the mixture of such, before or after spontaneous combustion. There is no mention of the active liquids obtained by distillation, which were called divine or sulphurous waters, and held an important place with the Greco-Egyptian chemists, and became the origin of our acids, alkalies, and other agents; they had not yet entered into industrial use, and are seldom met with previous to the fourteenth century.

The group of receipts transmitted by the formulas for dyeing, passed into a more extended collection called the Key to Painting, of which exist a manuscrip: of the tenth century in the library of Schlestadt and one of the twelfth century, of which an edition was published in 1847 by Mr. Way. The former manuscript is free from all Arabian influence, which has caused the interpolation of five additional articles in the second one. The work contains a treatise on the precious metals comprising now a hundred articles, about half of the original work, the other half having been lost, and a treatise on recipes for dyeing, representing principally those in the Formulas; together with sixteen articles on military ballistics and fireworks, forming a special group; articles on the hydrostatic balance and the densities of the metals; and industrial and magic recipes, added at the end of the book. The treatise on the precious metals is of great interest because of the striking analogies it presents with the Leyden Egyptian papyrus found at Thebes, and with other ancient works. Many of the recipes are literally translated from these ancient works; an identity proving indisputably the continuous preservation of alchemic practices, including transmutation, from Egypt down to the artisans of the Latin West. The theories proper, on the other hand, did not reappear in the West till toward the end of the twelfth century, after they had passed through the Syrians and the Arabs. But the knowledge of the processes themselves was never lost. This fact is demonstrated by the study of the alloys intended to imitate and falsify gold; for coloring (copper) gold-color; for fabricating gold; for making test gold; for rendering gold heavier; and for doubling gold. The recipes are filled with Greek words that betray their origin.

The object for the most part is simply to make base gold, as, for instance, by preparing an alloy of gold and silver, colored with copper. The goldsmith, however, tried to make this pass for pure gold. Then manufactures of complex alloys which were made to pass for pure gold were made easier by the intervention of mercury and sulphurets of arsenic, the use of which goes back to the earliest times of the Roman Empire. Thus Pliny relates