. The American journal of science and arts . veral. And on the otherhand, that the returns for the sale of the lead are at the price itbears at Galena with the merchants there, who make their profitsby shipping it to the eastern market. The slag furnace, of which a drawing is given on the next page,(Fig. 3,) is often connected with a blast furnace or a reverberato-ry, particularly when the smelter can obtain any of the old slagfrom the now abandoned ash furnaces to mix with what hemakes. At some furnaces the slag is beaten up under stampersand washed through a series of vats, but generally it
. The American journal of science and arts . veral. And on the otherhand, that the returns for the sale of the lead are at the price itbears at Galena with the merchants there, who make their profitsby shipping it to the eastern market. The slag furnace, of which a drawing is given on the next page,(Fig. 3,) is often connected with a blast furnace or a reverberato-ry, particularly when the smelter can obtain any of the old slagfrom the now abandoned ash furnaces to mix with what hemakes. At some furnaces the slag is beaten up under stampersand washed through a series of vats, but generally it is merelybroken by hammer into small lumps, and then thrown into thefurnace. The principle of the slag furnace differs from that of theblast furnace, in which the ore is exposed to the greatest oxidizingaction to be obtained ; the object being thoroughly to melt theslag and keep it in a fluid state until the metal separates itself, andboth run out together through the hole in front. The lead sinks Wisconsin and Missouri Lead Region. Fig. Furnace about four feet high, four feet deep, and five feet front. Tvveer introduced from behind, opposite the hole for the exit of the lead and slag. Fuel—charcoal. L, vessel to catch the lead. S, hole to catch the slag; in this runs a current of water. into the first vessel, the slag floats over it into the next, through?which runs a stream of water. Here it is cooled, and then ladledout and thrown away.* The amount of lead produced by oneof these furnaces, varies of course with the quality of the ONeills slag furnace on the Peccatolica, near Mineral Point,where the charge consists of the rich reverberatory furnace slag,and that from the old ash furnaces, twenty seven pigs of lead arefrequently obtained at one shift or days work ; twenty five, how-ever, are considered a good days work. The hands employed,are a smelter, back-hand, and assistant. Having given this particular account of the furnaces, I willnow enter into an examina
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Keywords: ., bo, bookcentury1800, bookpublishernewhavensconverse, bookyear1820
