fining of Silver, the Lead that is mix’d with it (to carry away the Copper or other ignoble Mineral that embases the Silver) will, if it be let alone, in time evaporate away upon the Test; but if (as is most usual amongst those that refine great quantities of Metals together) the Lead be blown off from the Silver by Bellowes, that which would else have gone away in the Form of unheeded steams, will in great part be collected not far from the Silver, in the Form of a darkish Powder or Calx; which, because it is blown off from Silver, they call Litharge of Silver. And thus AgricolaAgricola de Natura Fossil. Lib. 9. Cap. 11. & 12. in divers places informs us, when Copper, or the Oare of it is colliquated by the violence of the Fire with Cadmia, the Sparks that in great multitudes do fly upwards do, some of them, stick to the vaulted Roofs of the Furnaces, in the form of little and (for the most part) White Bubbles, which therefore the Greeks, and, in Imitation of them, our Drugsters call Pompholix: and others more heavy partly adhere to the sides of the Furnace, and partly (especially if the Covers be not kept upon the Pots) fall to the Ground, and by reason of their
