Note 94 — ZINC.

“White vitriol also is made at Goslar, but by one citizen only, named Henni Balder. It is not procured by the evaporation of copper like other vitriol; but when large quantities of ore are roasted in the furnaces, a red substance is from time to time collected on the refuse of the ore, and found in some places half an ell thick. This substance, which is saltish, is formed into a lye, and boiled in small leaden pans. The rest of the process I do not know, but I observed that it crystallizes like saltpetre, but is stronger and whiter. It is also cast into small cakes about the thickness of one’s hand. This vitriol is employed by the leather-dressers, and may be used for many things instead of alum; but it cannot be used in dressing white skins, because it makes them yellowish.”