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totally by any : And that its precipitates refill vitri- 
fication, and this perhaps in a more perfedt manner 
than precipitates of gold itfelf. 
PAPER III. 
Read June 
27, 1754. 
'THE two former papers have given 
A an account of the habitus or relation 
of platina to the principal fubftances, which adt up- 
on metallic bodies ; and fhewn, that it is a fimple 
metal, of a particular kind, eflentially diftindt from 
all thofe hitherto known, though pofleffed of fome 
properties generally fuppofed peculiar to gold. Many 
of its diftinguilhing charadters have been already 
pointed out : Others will refult from combining it 
with the feveral metals ; with each of which, not- 
withstanding its refiftance to the molt intenfe fires by 
itfelf, or with unmetallic additions, it melts perfedtly ; 
occafioning remarkable alterations in their colour, 
texture, and hardnefs. 
Article i. 
Platina with Tin. 
I. Equal parts of platina and pure tin were in- 
jedted into a mixture of black flux and common 
fait in ftrong fufion ; and urged with a quick fire, 
in a good blaft furnace. After a few minutes the 
whole appeared perfedtly melted ; and on being in- 
flantly poured out, run freely along a narrow mould, 
forming a fmooth ingot, nearly of the lame weight 
with the platina and tin employed. The compound 
proved extremely brittle, breaking eafily from a fall : 
Inter- 
