DISTRIBUTION OF COSTS— Amount. Per Dry Ton. Operating expenses, $111,687·17 $1·8593 Slag and matte expense, 5,111·07 0·0851 Boiler-house, 11,468·77 0·1909 General expense, 4,218·58 0·0702 Cost of flux, 817·46 0·0136 ————————- ——————- $133,303·05 $2·2192 Steam credit, 48,861·86 0·8134 ————————- ——————- Operating cost, $84,441·19 $1·4057 =========== ======= ANALYSIS OF COSTS— (1) _Operating_— Amount. Per Dry Ton. Labour, $17,829·42 $0·2968 Power, 592·36 0·0099 Fuel oil, 88,028·99 1·4654 Coal, 243·61 0·0041 Water, 91·68 0·0015 Transportation, 380·45 0·0063 Sundries, 315·64 0·0053 Flux, 817·46 0·0136 ————————- ——————- $108,299·61 $1·8029 =========== ======= (2) _Repairs_— Labour, $11,063·93 $0·1842 Supplies, 12,425·30 0·2068 Shop expense, 1,514·21 0·0252 ———————— ——————- $25,003·44 $0·4162 ———————— ——————- Total, $133,303·05 $2·2191 Steam credit, 48,861·86 0·8134 ————————- ——————- Net total, $84,441·19 $1·4057 =========== ======= _Gaseous Fuel._—The proposal to employ gaseous fuel in copper smelting dates from the introduction of this method of furnace-firing by Siemens 50 years ago. It is, however, not in general use, although at several smelters gas-firing is employed in furnaces for the refining of the metal. The chief difficulties have been in connection with the control of the flame, burning-out of the roof having been a not infrequent occurrence when employing gaseous fuel, and the method has been tried and given up at the Great Falls Smelter in Montana, and at several other works.