[ 595 1 
this Operation, the Platina had loft near a fifth 
Part of its Weight. 
According therefore to this Experiment, the Pla- 
tina docs not wholly refill; the Force of Lead in 
Coppellation ; bur, by repeated Operations of that 
kind with larger Quantities of Lead, may probably 
all be deftroy’d : And by fuch repeated Coppella- 
tions, Gold and Silver may very likely be refin’d 
from it j although what was before afferted may 
hold pretty true, with regard to the common Cop- 
pcllations of the Aftayers and Refiners. 
Mr. Wood faid, that, in his Experiment, he 
thought the Platina rather gain’d than loft in 
Weight by Coppellation. This might happen from 
fome fmall Mixture of Lead, or other Meral conti- 
nuing with it after it remained no longer fufed. 
From this fingle Experiment I will not be quite 
pofitivc that Lead thus confumes fome fmall Quan- 
tity of Platina^ fince it is poflible the Platina ufed 
might not be pure. Befides, in order to keep] it 
longer in Fulion, I urged on the Experiment with 
an uncommon Degree of Heat, efpecially towards 
the End of the Operation j although I think no 
great Errcr could thence arife ; as half a Drachm 
of Silver, which I coppeli’d at the fame time, had 
loft only two Grains in the Operation. 
I am told that one Mr. Ord, formerly a Faelor to 
the South Sea Company , rook in Payment from 
fome Spaniards Gold, to the Value or yoo l. Ster- 
ling, which being mix’d with Platina , was fo brit- 
tle, that he could not dilpofe of it, neither could 
he get it refin’d in London , fo that it was quire 
ufelcls to him: Altho’, if no Error hath been com- 
G g g g mitted 
