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

THE METALLURGY OF ANTIMONY. 71
rows at regular distances apart, each having from twenty to thirty pots.
The rows of pots are separated from one another by walls of dry
masonry, and fuel (coal or wood) is used to fill the spaces between
the pots, and between the pots and the walls. The time required
for one shift of the pots varies according to the amount of the charge,
FIG. 4.
a, 0*5 m. high, 0'29 m. broad above,
0*24 m. below, with five holes, each
13 mm. wide.
by Belly-shaped vessel, 0*24 m. high,
0*26 m. wide at belly, 0*21 m.
above and below.
c, Fireplace.
d, Leading to flue, e.
generally from two to twelve hours. At the conclusion of each shift
the pots are lifted off from the receivers, emptied of their residues,
again charged, and finally placed in position. The receivers may be
emptied after each charge or when they are full. The residues contain,
generally, not less than 12 per cent, of the sulphide.
Fig. 3 shows the arrangement of this method as used at Wolfsberg
;n the Harz. a is the pot; 6, the receiver; #, the non-conducting