different ores, and the data on which it may be estimated 
in analysis,. 
Lead is readily separated from silver by making a so- 
lution of both in nitric acid, and adding muriatic acid as 
long as any precipitate appears. 
The silver falls down in the form of luna cornea, and 
with it a quantity of muriat of lead, and if the mixture 
stands some hours undisturbed, this latter salt also forms 
needled crystals on the surface of the luna cornea. All 
the silver falls down in this manner, but part only of the 
lead, and the muriat of lead is separated from the lima 
cornea by boiling water, 22 parts of which will dissolve 
1 of muriat of lead, but not a particle of muriat of the 
silver. The solution of the muriat of lead is still more 
easily effected by digesting in dilute nitric acid, which 
dissolves it readily, but not the luna cornea. 
Lead is separated from bismuth by dissolving both to 
saturation in nitric acid, either concentrated, or diluted 
With no more than a fourth of water, and then pouring 
the concentrated solution into a large quantity of water. 
The oxyd of bismuth then separates as a heavy white 
powder, and the lead remains dissolved. Some bismuth 
however remains, but to the solution may then be added 
a saturated solution of siilphat of soda, which will precb 
pitate the lead only in the form of a white pulverulent sub 
phat of lead, the composition of which will be presently 
mentioned. But where all the bismuth is to be obtained 
for the purpose of analysis, and not merely to be separat- 
ed from the lead, it is better after the bismuth has first 
precipitated, to add muriatic acid to the clear solution^ 
which will throw down the silver, if there be any, and also 
some muriat of lead, mixed with some of the bismuth 
that remains m the solution, and which last if redissolved 
in nitric acid, will again be decomposed by water as be- 
fore. The whole muriat of lead may then be dissolved in 
