of the Fire, lose its colour, and acquire sometimes a gray, sometimes a yellowish, sometimes a red, sometimes an amethihstine colour; and after having past through these, and perhaps divers others, again recover its leaden colour, and be made a bright body. That also this Lead, which is so flexible a metal, may be made as brittle as Glasse, and presently be brought to be again flexible and Malleable as before. And besides, that the same lead, which I find by Microscopes to be one of the most opacous bodies in the World, may be reduced to a fine transparent glasse; whence yet it may returne to an opacous Nature again; and all this, as I said, without the addition of any extraneous body, and meerly by the manner and Method of exposing it to the Fire.
But (sayes Carneades) after having already put you to so prolix a trouble, it is time for me to relieve you with a promise of putting speedily a period to it; And to make good that promise, I shall from all that I have hitherto discoursed with you, deduce but this one proposition by way of Corollary. [That it may as yet be doubted, whether or no there be any determinate Number of Elements; Or, if you please, whether or no all compound bodies, do consist of the same number of Elementary ingredients or material Principles.]