TREATMENT OF SULPHURET ORES AT CHARACTERISTIC MINES. 139 concentrates per 24 hours for each furnace. The revolving pan-furnace is worked by three men per 24 hours, with the same output as the doublehearth. The fumes from these furnaces carry off into the air the equivalent of 13 tons of 50 per cent, sulphuric acid. The management has investigated the erection of lead chambers, but so far have not considered such an installation to their advantage. The Spence furnace has
	been tried at the Haile, without success.1 The roasted ore after coolingis elevated to the top floor of the chlorination house, 32 feet high. This consists of a four-story frame building, containing 3 chlorination-barrels, 11 filtering-tanks, 2 storage-tanks, and 13 precipitating vats (see figs. 28, 29). The ore is charged through a hopper into the chlorination- 1 See paper by A. Thies and W. B. Phillips, " The Thiea Process of Treating Low-grade Auriferous Sulphides at the Haile Gold Mine, Lancaster Co., S. C," Trans. Am. Inst. Min. Eng., xix, 601.