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The cost of smelting with five furnaces in operation, each treating three charges per day, was approximately as follows:

1 foreman at $3 $3.00 5 furnace crews at $9.90 49.50 Unloading 21 tons of coal at 6c. 1.26 Loading 14 tons lead at 15c. 2.10 Loading 7 tons gray slag at 15c. 1.05 Total labor $56.91 21 tons coal at $2 $42.00 Flux and supplies 13.00 Blacksmithing and repairs 10.00 Total $121.91

On the basis of 6.25 tons of wet ore, this would be $4.65 per ton. The actual cost in seven consecutive months of 1900 was as follows: Labor, $1.98 per ton; coal, $1.86; flux and supplies, $0.51; blacksmithing and repairs, $0.39; miscellaneous, $0,017; total, $4.757. If the cost of smelting the gray slag be reckoned at $8 per ton, and the proportion of gray slag be reckoned at 0.25 ton per ton of galena concentrate, the total cost of treatment of the latter comes to about $6.75 per ton of wet charge, or about $7 per ton of dry charge. This cost could be materially reduced in a larger and more perfectly designed plant.