Note (19) — BOOK V.

19. Cadmia.) The best is the Cyprian, called botryitis, solid, moderately heavy, being clustered like a bunch of grapes, of the colour of spodium, and being broken it appears cineritious and eruginous within. There are other kinds of it inferior, known by the names onychitis, zonitis, and ostracitis. For burning cadmia it is hid in live coals, till it grows diaphanous, and runs into bubbles like the scoria of iron; afterwards it is extinguished in Aminæan wine. Some burn it thus three times, till it be perfectly converted into ashes; and then they use it instead of spodium. It is washed in a mortar, and the water changed, till no dross appears on the top. Dioscorid. lib. v. cap. 858.—I have here mentioned particularly the burning and washing of cadmia, because it may serve to shew the nature of this process in other minerals, when our author prescribes such; and Dioscorides in mentioning them often refers to cadmia as the general example.