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[ 5 6o ]

fluid. The matter continued to flow, and to fume copi-ously, for some hours: at length it became consistent in anintense white heat, and scarcely emitted any more fumesthough strongly blown on. The mass, when grown cold,broke easily, appeared very porous, blebby, of a dull greycolour, and weighed considerably more than the quantityof platina employed. Its specific gravity was only about

J 5-

This experiment was several times repeated, and theevent was always the same; the platina not only resisting,as gold does, the volatilizing power of the antimonial regu-lus, but likewise defending a part of it from the action ofthe fire and air, and refusing to melt after a certain quantityhad been dissipated.

I likewise treated platina with crude antimony. Fourounces of antimony and two ounces of platina, kept forsome time in a fire pretty strongly excited by bellows, ap-peared melted only in part : four ounces more of antimo-ny being added, and the fire renewed, a reguline matterwas found partly at the bottom and sides of the crucible,and partly intermingled among black spongy scoriæ: thewhole was returned to the fire with black flux and com-mon salt: it now melted sufficiently thin, and the regulusperfectly separated. This regulus did not differ in ap-pearance from mixtures of regulus of antimony and platinamelted together, and exhibited the same phenomena alsoon trying to blow off the antimonial part.

Mr. Scheffer likewise tried platina with antimony, andthe result of his experiments was the same as of mine.He observes that as platina resists sulphur equally withgold, it cannot be scorified by the sulphureous part of an-timony, and therefore remains, as gold does, in the regu-lus ; but that the regulus cannot be blown entirely offfrom it, as it is from gold, on account of the platina notcontinuing fluid.