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remained of a high colour, resembling that of the deeperchives of saffron. In a moderate heat, they seemed tomelt, though only imperfectly, and emitted white fumessmelling of spirit of salt; at length they fell into a duskyash coloured calx, staining the tobacco-pipe, in which theywere exposed to the fire, of a pale dull reddish colour,

III. Volatilization of Platina.

This metal, of itself as fixed in the fire as gold, appearsto be equally volatilized by the hasty abstraction of an aquaregia made with sal ammoniac. Marggraf put into a glassretort six ounces of a solution of platina made in a mix-ture of sixteen parts of aquafortis and one part of sal am-moniac : having set the retort in sand, and fitted to it areceiver, he drew off the liquid by a gradual fire, which atlast was increased, so as to make the retort red hot andready to melt. There remained at the bottom a reddish -brown powder,which being further calcined under a muf-fle, became more of a brilliant blackish hue. In the neckof the retort was found a brown-red sublimate, which, onexposure for some days to the air, run into a red liquorresembling solution of platina. He poured some of thisliquor on a poliihed copper plate, and found that the pla-tina, after some time, precipitated upon the copper, as itdoes from its common solutions, covering the copper witha shining blackish powder.

IV. Solution of platina, with vitriolic acid.

To a solution of platina, diluted with water, I addedsome strong spirit, called oil, of vitriol: no precipitationor change of colour ensued, though a large quantity of theacid was at different times dropt in, and the mixture suf-fered to stand for several days. But on adding the samestrong vitriolic, spirit to an undiluted solution of platina,

the