[5i8 ]

nally smooth, and of a bright white colour like quick-silver, very brittle, internally greyish, of a spongy texture,,with some few of the grains of platina left entire in themiddle: the crucible was lined with a black glass, pro-bably a vitrification of the ferrugineous part of the platina;and several shining metalline globules adhered to the vi-treous matter. The lump was again dropt into a stronglyheated crucible, with more arsenic and charcoal powder,and the st re excited by the bellows for another half hour:it melted as before, into a cavernulous mass, in which nograins of platina could now be seen. It was again treatedin the same manner with fresh arsenic, and tried to bepoured out; but-though the; fire was made very intense,the metal would not run from the crucible. Being thenurged in a quick sire without addition, it concreted into alump of the same appearance as before: but a piece ofthis lump, dropt again into a crucible intensely heated, didnot seem to soften or suffer any alteration of its figure';The rest of the lump was inclosed between two smallpieces of charcoal, a cavity being made in each piece forreceiving it: the charcoal was coated over with luting,and, when thoroughly dried, dropt in among the fuel be-fore the nose os the bellows: the metal did not alter itsfigure, nor was its weight diminished. I took half anounce of the metal, and arsenicated it again in the samemanner as at first, adding at different times more andmore arsenic: it run into a lump as before, but I couldnot, by any increase of the fire, or by any addition ofarsenic, make it thin enough to flew from the crucible.I took half an ounce more of platina, and having com-bined with it as much arsenic as I could by repeated in-jections, I reduced the mass into gross powder,, mixed itwith black flux and some fresh arsenic, and urged it witha quick fire in a covered crucible: the metal run into a

spongy