« 
Fig. 3. 
Furnace about four feet high, four feet deep, and five feet front 
Tweer introduced from behind, opposite the hole for the exit of the lead and slag. 
- Fue!l—charcoal. 
L, vessel.to eatch the lea 
8, ie to catch the ly > in this runs a current of water, 
into the first vessel, the slag floats over it into the next, ehedwet 
which runs a stream of water. Here it is cooled, and then ladled 
out and thrown away.* ‘The amount of lead piciaicied? by one 
of these furnaces, varies of course with the quality of the slag. 
At O’Neill’s 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 are 
) ‘obtained at one shift or day’s work: twenty five, how= 
ote: are considered a a good day’s work. ‘The bcs i a ah 
are a smelter, back-hand, and assistant. © 
Having given this pitted eee oat of 7 sche? t will 
now enter into an examination of the lead business taken asa 
whole; and most of the data for the estimate I shall take from 
the report of Dr. Owen. 
Tbe whole number of furnaces in Iowa, Tllinois, sid the terri- 
tory of Wisconsin, he judges to be fifty. ‘This was in the year 
1899); since sia there has’ been no great variation in the tie 
2 Bi is supposed this glassy priait is pid fin of metal ; but having sokisnaieth it 
ing in nitric acid, separating the silica, throwing down the lead as a sul- 
phoret by hydrosulpburic ‘itd, and sheen into sulphate of lead, I found 
Tol. 1h, Nu Eeaigtl Sane, 1842. 7 
