A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...

THE METALLURGY OF ANTIMONY.
with a better control of the oxide and of the smoke coming from
the fireplace.
The two kinds of reverberatory furnaces now in actual use for
roasting are rabble furnaces and long-bedded hand-furnaces (Germ.
FortscJiaufelungsofen).
The rabble furnaces were used formerly at Bouc and Septtmes in
France. Fig. 17 shows a plan view, while fig. 18 shows a section
across A B. a is an egg-shaped horizontal bed, 8 ft. 3 ins. long,
4 ft. 7 ins. wide at its greatest width; r r are fireplaces, 5 ft. 3 ins.
FIG. 16.—Front view. Scale=TV.
A, Cover for the muffle.
B, Hole for the admission of
air.
O, Heating space.
D, Fire-brick.
E, Ordinary brick.
F, Door for fuel.
G, Grate.
H, Ash-pit
J, Exit for smoke.
long and 1 ft. 2 ins. wide; b, door for working; d, flue leading
to the main chimney; /, hood for the removal of antimonial
fumes from the furnace-men. In six hours 5 to 6 cwts. of
ground and sifted ore can be roasted in such a furnace; the door
must be closed during the first two hours, but toward the end
it is opened so that the workmen can stir and rabble the charge
well. The loss of antimony in well-executed roasting is about
2 per cent.
At Siena the method of working is thus:—4 cwts. of fine ore
charged at one time. Time of roasting = 3 to 12 hours, according to
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