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brilliant parts, and appeared to be intermixed with preci-pitated platina: the liquor continued yellow.

XV. Platina , Bismuth, and Acids.

The author above-mentioned relates, that on digestingbismuth in solution of platina, the effect was nearly thesame as with regulus of antimony, the bismuth appearingcorroded, a white powder settling at the bottom, and theliquor continuing yellow: and that solution of bismuth inaquafortis being mixed with solution of platina, no preci-pitation happened.

The experiments in the five last articles of this section:are too obscure and ambiguous for points of such impor-tance as the affinities of bodies to be established on them;but those of the first ten seem to be sufficiently, clear anddecisive. It may be observed, that in some of these affini-ties platina agrees with gold, as in being precipitated fromaqua regia by zinc, iron, copper, tin, and quicksilver; butthat in others, it differs so essentially from gold,, that whenthe two metals are intimately combined together by longfusion, they may still be parted from. one another in virtueof this contrariety in their affinities to particular bodies.,platina being rejected by quicksilver while gold is retained,,and gold being rejected by aqua regis, when vitriolic so-lutions of iron are added, while platina is retained.

SECT. IX.

Of distinguishing and purifying Gold mixed with Platina.

r E have now finished a laborious examination of the

V V properties of this new metal and its relations to ;other bodies. One of the most important advantages, thatwere expected to result from this enquiry, considered in acommercial view, was the preserving of the fineness and

value