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fragments hung together by the outward golden 
coat. 
7. Mixtures of platina and filver, fubmitted to 
cupellation, retained likewife a confiderable quantity 
of the lead. Thefe, in becoming confident, formed, 
not an hemifpherical bead, but a flat mafs, very 
rough, and brittle, and of a dull grey colour both 
internally and externally. 
2. Cupellation and Scorijication of Bifmuth with 
Platina. 
Mixtures of platina with bifmuth, a metallic fub- 
dance, in fome refpedls more adlive than lead, were 
cupelled under a muffle, fcorified in afl'ay-crucibles, 
teded before the nofe of a bellows. In numerous 
repetitions of thefe experiments, the event was the 
fame, as when lead was made ufe of. The mixtures, 
which at fird flowed eafily, became lefs and lefs 
fuflble, in proportion as the bifmuth was driven off j 
and at length could not be kept fluid in an intenfe 
white heat, though they appeared, on weighing, to 
retain a conflderable proportion of the bifmuth. Nor 
could this femi-metal, any more than lead, be intirely 
feparated, by cupellation, from mixtures of platina 
with either gold or diver. 
Platina cupelled with bifmuth, differed little in 
appearance from that, which had been treated in the 
fame manner with lead. The button was more 
fpongy, and lpecidcally lighter. 
3. Dijfation 0/Regulus of Antimony with Platina. 
A mixture of platina and regulus of antimony was 
melted, by a drong Are, in a lhallow wide crucible, 
and 
