tien 
AND OTHER METALS FROM PYRITES. 109 
so low as to prevent the reduced iron from agglutinating into 
masses.. At the end.of eight hours the reduced metal i is with- 
n 
o 
od 
@ 
ag 
o 
é 
3 
@ 
rent acce 3 
The furnace i is again charged from the recess, ‘which has sac 
while been fi 
When the aes is cool enough to be handled, the contents 
are rapidly transferred to a vessel containing water, st by 
placing = gig over her vessel and withdrawing aslide in 
: a pene as at once to thordashig wet me cool the 
in the upper s of the combination r, over Naik 
water from the condenser, charged wi sulphurous and sulphuric 
acids, is flo e hour the charge is moved to the second 
ge, and a nd charge is intro , and so on iit in eight 
chamber is filled, and that furnace charge exhausted 
m ra on. by the acids, and converted into 
sulphate, sulphite, and hyposulphite of iron, but by the combined 
the first largely predominates. The ee on the shoo bee 
which removes sulphate of iron (also zine, nickel, and cobalt if 
present), and leaves a residue containing the go = silver, 
mixed with quartz, excess of -ecarbon, and free sulphu 
uartz 
otherwise. Ifthe extraction o the sulphate of iron is effected 
with boiling water, <7 the liquor run into coolers, that salt may 
marketabl 
calcined at a dull-red heat yield a fine red oxide of iron suitable 
for painting, and sulphuric acid which may be condensed. 
If the ores contain copper in oie ae rtion hips leg e roast 
ing, reduction, and solution of the iron are conducted reecionly 
from. The « copper is then found in the residue principally as. 
sulphide. This residue is — a dull-red heat, sat th 
re) 
densation of ‘the gases being conducted as before. The well- 
roasted ore is withdrawn from the furnace and cooled. The 
H 
