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yet so tough, as not to be broken by repeated blows of afledge hammer, from which it received some impression.Heated red, it broke easily, and looked internally of anuniform texture, not composed of bright plates as the ironwas at first, but of very dark coloured grains which had nometallic lustre.

3.. One ounce of platina being thrown upon four ouncesof cast iron beginning to melt, and the fire kept up strong,the whole came quickly into fusion. The compound, likethe foregoing, was extremely hard, and seemed to stretcha little under the fledge hammer, without breaking. Thetexture was grained, as before, but the colour somewhatless dark.

4. One part of platina and twelve of iron melted with-out difficulty, and with little or no loss. This mixturealso was much harder than the iron at first, and receivedsome impression from the hammer. Like the others, itcould not be broken while cold without extreme violence,but proved very brittle when heated red.

5.. All the foregoing compositions received a good pc-liffi. The first, in keeping ten years, has suffered no sen-sible change ; the second has some small specks of tarniffi,and the third is tarnished somewhat more, but not so muchas a piece of the iron itself.

6. About an ounce of a composition of one part of pla-tina and four of iron was surrounded, in a crucible, withReaumurs steel-making mixture, composed of eight partsof wood foot, four parts of wood assies, four of charcoalpowder, and three of common fait: the crucible was coveredand closely luted, and kept in a strong red heat for twelvehours. The metal gained an increase of about one thirty-ninth of its weight, yielded to the file more easily than atfirst, seemed to receive no additional hardness on being ig-nited and quenched in water, and did not appear to have

acquired