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strokes it bore to be considerably flattened. Internally itappeared of a much duller and darker colour than silver,and of a much coarser grained texture.

2. One part of platina and two of silver, covered withnitre and common salt, did not flow thin till the fire wasraised to a strong white heat, and, when poured out, leftmany small particles adhering about the sides of the cru-cible. The metal proved less brittle than the foregoing,and not so hard to the file: its texture was finer grained,and the colour whiter.

3. One part of platina and three of silver required alsoa very strong fire for their perfect fusion, and many par-ticles of the metal were thrown up almost to the top of thecrucible, as if the action of the silver upon the platina hadbeen accompanied with a kind of ebullition or explosion.The compound was hard and brittle, though less so thanthe preceding : by repeated nealing, it bore to be ham-mered, or flatted between steel rolls, into thin plates.

4. One part of platina and seven of silver melted toge-?th er pretty easily, but a part of the metal was thrown upabout the crucible as before. The compound hammeredtolerably well, proved much harder than silver, and not sowhite, nor of so fine a grain.

5. In the foregoing experiments, the quantity of platinawas from ten to twenty grains. I tried sixty grains ofplatina with four times, eight times, twelve times, twentytimes, and thirty times as much fine silver. One of thesemixtures was treated without any flux, another was co-vered with borax, another dropt into borax previouslybrought into fusion, another into melted black flux, andthe last into melted common salt: the fire was stronglyexcited by the bellows, and all the mixtures suffered tocool in the crucibles. With these larger quantities of thetwo metals, the phenomenon above taken notice of was

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