[ 6 5 a ] 
Remark. It appear’d, that by this method of 
managing the procefs, one part of platina was dil- 
foluble in about four and a half of aqua regia : But 
that when the digeflion was perform’d in open veflels 
in the common manner, and the fumes, which arile 
copioully during all metallic diffolutions, fuffer’d to 
exhale, more than half as much again of the men- 
ftruum was requifite. This procefs might therefore 
poffibly be applicable to advantage, in making folu-, 
tions of metals in the way of bufmefs. 
Examination of Solution of Platina. 
Experiment i. 
As the vitriolic acid carries down metallic bodies, 
gold not excepted, from their folutions in other men- 
flrua j this acid was mix’d with folutions of platina. 
1. When the folution of platina was previoufly 
diluted with water ; the addition of dephlegmated 
fpirit of vitriol occalion’d no precipitation, or change 
of colour, tho’ a large quantity of the acid was, at 
different times, dropp’d in, and the mixture fuffer’d 
to hand for feveral days. 
2. Dephlegmated fpirit of vitriol, added to an un- 
diluted folution of platina, immediately render’d it 
turbid, and threw down a dufky-colour’d precipitate. 
The precipitate was not re-diffolv’d on the affufion 
of water ; nor was the precipitation prevented by 
adding water immediately after the acid had been 
dropp’d in. 
Expo 
