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with a strong fire : the metal was of a filver whiteness,and weighed seventy grains : the scoria was caustic, livercoloured, and when liquefied in the air looked greenish.The regulus was melted again, with half an ounce of thepurest nitre and a dram of borax : the scoria proved clou-dy, inclining to yellow underneath and to greenish above :the regulus was of a fine white, and weighed still seventygrains ; it had something particular in its appearance onthe surface and about the sides, resembling the radiatedcobalt; it stretched pretty well under the hammer, andbore to be flatted into a thin plate, but was harder thanfine silver. A part of this plate was digested in purifiedaquafortis : the menstruum became first of a high grafs -green colour; afterwards, in a boiling heat, the plate grewblack, and the solution brownish. The silver being atlength dissolved, there remained at the bottom a blackponderous matter like calx of gold. This was thoroughlywastied with hot distilled water, then dried, and made redhot, but it received no gold colour. It was mixed withgranulated lead, and the mixture worked first on a scorify-ing dish, and then on a cupel : there remained a convexbead, without metallic lustre, which sprung under thehammer, and resembled the other beads obtained by cu-pelling platina with lead.

13. It appears upon the whole, that Marggrafs trialsfor working off lead clean from platina, succeeded nobetter than Scheffers and mine, so much of the lead beingalways retained as to make the metal very brittle, whereasplatina by itself, whether in its crude state of grains orwhen melted by a burning-glass, is of considerable malle-ability. Macquer and Baume made another effort: theywere " desirous of seeing, whether a heat of a good deallonger continuance would not produce that, which onecoup de feu, perhaps more strong but of shorter duration,.

had'