BOOK IX.

435

Others reduce the ore in iron pans as next described. They lay smallpieces of dry wood alternately straight and transversely upon bricks, one anda half feet apart, and set fire to it. Near it they put small iron pans linedon the inside with lute, and full of broken ore ; then when the windblows the flame of the fierce fire over the pans, the bismuth drips out of theore ; wherefore, in order that it may run, the ore is stirred with the tongs ; butwhen they decide that all the bismuth is exuded, they seize the pans withthe tongs and remove them, and pour out the bismuth into empty pans, andby turning many into one they make cakes. Others reduce the ore, when it isnot mixed with cadmia , 60 in a furnace similar to the iron furnace. In thiscase they make a pit and a crucible of crushed earth mixed with pulverised

A —Wood. b—Bricks. C— Pans. D —Furnace. E— Crucible. F —Pipe.

G— Dipping-pot.

charcoal, and into it they put the broken ore, or the concentrates fromwashing, from which they make more bismuth. If they put in ore,they reduce it with charcoal and small dried wood mixed, and if concentrates,they use charcoal only; they blow both materials with a gentle blast from

• c ^ m i a i s given in the German translation as kobelt. It is probably the cobalt-

arsenic-bismuth minerals common in Saxony. A large portion of the world’s supply ofismuth to-day comes from the cobalt treatment works near Schneeberg. For furtherdiscussion of cadmia see note on p. 1x2.