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tained in the cupellation of crude platina, and weighedabout half a grain. This little bead was put upon a freshcupel, with one grain of gold that had been parted withsilver, and twenty grains of granulated lead: after cupel-lation, he had a fair gold button, yet still somewhat flat,curled, and with a kind of net-work on the surface, in co-lour like gold but paler, weighing exactly two grains, hardindeed, but bearing pretty Well to be reduced into plates..To this he added four grains of the finest laminated silver,and twenty grains of granulated lead; and on repeating thecupellation obtained a button not yet quite round, andweighing five grains- He flatted it, for it was considerablymalleable; made it red hot; and tried to part it with puri-fied aquafortis: but the aquafortis, though made to boil,would not sufficiently act on it. He therefore poured offthe aquafortis, and found the plate very little corroded.After washing it several times with distilled water, andheating it red hot, it weighed four grains, and was foundto be brittle, and just perceptibly yellowish. He added toit six grains more of fine silver, with twenty grains of gra-nulated lead, and cupelled again: the button weighedthirteen grains, and consequently had gained an increase ofthree grains. It was very malleable, and being flatted,made red hot, and digested in purified aquafortis, the aqua-fortis attacked it briskly, leaving some black plates, whichbeing washed, and ignited under a muffle, appeared of afine gold colour, and weighed one grain.”

In this last experiment it is probable, that the smallnessof the quantity occasioned some deception. If we concludefrom it, that the yellow particles were not gold, becausethe gold that was melted with them was recovered withoutincrease ; we must conclude for the same reason, either thatthey were not platina, or that the platina was destroyed inthe cupellation or dissolved by the pure aquafortis. The

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