C 5*4 ]

preceding. Its texture was finer, and composed chieflyof transverse fibres, with very few grains.

7. A mixture of one part of platina and twenty-four oflead proved not very much harder than lead of a middlingquality. The colour was still somewhat purplish, and thetexture fibrous; but the fibres were remarkably finer thanwhen the platina was in greater proportion.

8. The four first of the foregoing compositions, whennewly polished, appeared of a dark iron colour, whichquickly tarnished to a brownish yellow, a deep purplish,and at length to a blackish. The three last, cut with achisel, looked of a leaden hue, which tarnished but little';though the fractures, and outer surfaces, of all the sevenhave changed nearly to a like purplish black.

9. Upon returning these compounds to the fire a secondtime, it was constantly observed, after they had come intoperfect fusion, that if the heat was stackened a little, greatpart of the platina subsided : that nevertheless, the lead de-canted off even in a heat below ignition, retained so muchof the platina, as rendered it of a fine fibrous texture andpurplish colour.

10. The several mixtures, covered with black flux, andkept in strong fusion, in crucibles closely luted, for eighthours, suffered a diminution in weight, amounting, in mostof them, to about one thirtieth part of the lead. Onbreaking them, those with a large proportion of platinaappeared of a leafy, and those with a smaller of a fine fibroustexture, which seemed in general to be characteristics ofthe perfect union of the platina and lead. They all lookedwhiter and brighter than at first, but tarnished sooner inthe air. One mixture in particular, of four ounces of pla-tina and twelve of lead, broke into large, white, shining,talk-like flakes; which, on exposure to the air, changedin a very little time, in less than an hour, to a reddish,

a: purple,