Page:Philosophical Transactions - Volume 003.djvu/196

 they divide themselves into many lesser spangles, as with a little rubbing they leave one's hand all guilded over like gold.

I knew well enough, that the ordinary Tryals made by the Indians, had proved fruitless upon this Mineral; for it could neither be reduced into a massy form by the violence of fire, nor separated from its heterogeneous substances by the mild tryal of Quick-silver, yet on the Touch-stone it equalized the most refined gold; so that there wanted nothing but to reduce it to at fusible and malleable metallick Form; which soon would be accomplished, if it could be made to take Quick-silver.

Considering with my self, what might be the reasons of its refusing Mercury, and being not ignorant, that some of the choicest Mines of Silver and Gold, are almost of the like nature, till the impediments are remov'd, which are certain mineral viscosities, that sometinres by their oleaginous fatness, and at other times by a fretting acrimony, hinder the ingress of the Mercury; I conceiv'd, the like might happen in this case. Whereupon, to find a cure for this disease, I began first to make experiment on the sand, which had been the matrix of the Mineral; and there I tryed first the ordinary way used in the Indies on such occasions, which was, to observe the colour of the fumes, yielded from the spang1ed sand in a strong reverberating fire; but here could little be observed, by reason of the adust drying of the sand, not able to afford any visible fumes; fit for such a discovery Likewise I proceeded to another way, to boyl it in water, and having powred that off, to observe the Alcali, left after the waters evaporation, I by this means dis'cover'd, that it abounded rather in sulphureous unctuousness, than saline acrimony; or else I think, my eyes in the Cave had run a greater hazard. Finding this, I applyed first the Quick-silver, mingled with the ordinary Magislrals (as they call them) used in that Country, to curb and break the force of these sulphureous impediments. But perceiving these to be of no effect, I encouraged the Quick-silver with the Caput mortuum of Vitriol and Salt-peter, (kept as a secret among the chiefest Mine-men) but with as little signs of the Mercury's operation as before. Then I boyled my mixture over the Rh