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A mixture of equal parts of platina and copper (No.i.of the above experiments) was tried by Mr. Scheffer, wboreports, that they melted as easily as copper by itself ; andthat the mixture proved tolerably malleable, as mixturesof gold with a like quantity of copper: in both thesepoints, the little quantity he could allow for the experimentmay be supposed to have occasioned some deception. Headds, that when this compound is urged by a strong blastimpelled upon the surface, as in the purification of copperbefore the bellows, it throws out sparkles like iron inwelding, and that these sparkles are found in form of roundgrains, which partake of both the metals j a phenomenonwhich gold does not exhibit with copper. After thisoperation, he found the mixture less malleable than before,like copper over-refined.

XI. Platina with Copper and Zinc.

1. Equal parts of platina and brass, covered withborax and exposed to a quick fire in a blast furnace, meltedperfectly together, and suffered very little loss. The mixtwas of a greyish white colour, filed hard like bell-metal,broke from a blow of the hammer without stretching orreceiving any impression, and flew asunder upon endeavour-ing to cut it with a chisel. Internally, it appeared of anuniform fine grain, a close texture, and a darker colourthan on the outside. It bore a very fine polish, which inten years does not appear to have at all tarnished.

2. One part of platina and two of brass, melted togetherin a stow fire, lost about one thirty-sixth. The ingot wasof a duller colour than the foregoing, with a faint yellow-ish cast. It filed softer, and broke less readily from thechisel, but cracked and fell in pieces under the hammer.It received a good polish, and continues untarnished.

3. One