Thus the level of the lead is kept approximately constant, and the silver becomes concentrated in the lead.
The character and amount of the flux necessarily depend upon the character of the ore, the object being to concentrate in the lead button all the gold and silver while dissolving and carrying off in the slag the other constituents of the ore.
But even in entirely new distributing systems the network is so extensive, and the number of joints so great, that the aggregate leakage is always considerable; the greatest loss being at the so-called " ferrules " connecting the mains with the house " communication " or " service " pipes, in the lead pipes, and in the household fittings.
But this important invention was of little use until John Glover, about 1866, found that the nitrous vitriol could be most easily reintroduced into the process by subjecting it to the action of burner-gas before this enters into the lead chambers, preferably after diluting it with chamber acid, that is, acid of from 65 to 70%, H 2 SO 4, as formed in the lead chambers.
The flow of the current will produce a fall of potential ER'/R in the lead from cold to hot, and ER"/R in the iron from hot to cold, but the potential difference due to the Peltier effect at either junction will not be affected.