[ 6 77 ] 
pearance greatly refembled the foregoing, but was 
found, on proper trials, to participate much more 
largely of the mercury and lead than of platina. The 
amalgam, which was of a very dull colour, on ex- 
pofure to the fire fwelled and leapt about, though 
the heat was fcarce fufficient t© evaporate the quick- 
filver. After conftant and rapid agitation with water, 
occafionally renewed, in an iron mill, for a week, 
it looked bright and uniform, and fuffered the mer- 
cury to exhale freely. A dark-coloured calx remain- 
ed, which proved, upon examination, to be platina, 
with a very little lead. 
Remark . Mercury is fuppofed to have a greater 
affinity with lead than any other metallic body, gold 
and filver excepted. In this experiment, it had a 
greater affinity with platina than with lead, fince it 
retained moft of the platina, after the lead, which 
was in much larger proportion, had been almoft in- 
tirely thrown out. The part of the platina, which 
the mercury rejedted at flrft, and that which it re- 
tained to the laft, did not appear diffimilar to one 
another, or different in quality from the platina em- 
ployed. 
3. A mixture of one part of platina and two of 
gold, which proved very white and brittle, after be- 
ing repeatedly nealed, was cautioufly flattened into 
thin plates, and thrown red-hot into boiling quick- 
filver. On trituration and ablution with water, a 
powder feparated, copioufly at firft, and by degrees 
more fparingly. After the procefs had been continued 
about twenty-four hours, there was no farther fepara- 
tion, except of a very little blackifh matter, into which 
a part of the mercury is always changed in thefe 
kinds 
