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Turning now for a moment to the costs of smelting raw and of smelting after a preliminary roast, we find that (in the case of the two works we have been considering) the results are all in favor of smelting raw, so far as a galena carrying nearly 80 per cent. is concerned.

The cost of smelting, per ton of lead produced, is given herewith:

ORE SMELTED RAW

Smelters’ wages $2.04 Smelters’ coal (425 lb.) 0.38 Total $2.42

A very small quantity of lime is also used in this case for some ores, but its cost would never amount to more than 4c. per ton of lead produced.

ORE RECEIVING A PRELIMINARY ROAST

Roasters’ wages $0.61 Roasters’ coal (425 lb.) 0.65 Smelters’ wages 1.08 Smelters’ coal (75 lb.) 0.11 Peat and lime 0.08 Total $2.53

It should be noted also that the smelters at the works where the ore was not roasted receive higher pay. In the eight-hour shift they produce about 1½ tons of lead; and as there are two of them to a furnace, they make $3.06 between them, or $1.53 each. The two men smelting roasted ore produce about two tons in an eight-hour shift, and therefore each receives $1.08 per shift.