Eureka daily sentinel. [volume] (Eureka, Nev.) 1871-1887, 1877-01-25
OUR SMELLING FURNACES.
How Bullion is Produced.

We have mentioned our furnaces
in u desultory way, but do not remem-
Der having seen any detailed descrip-
ton Of their workings, although it is
generally conceded that the furnaces
in use here are as..perfect in construc-
ton and capacity, and do closer work
on argentiferous ores than any In other
localities. In fact, a smelter who has
furnaces has a reputation that no other
place gives, a sort of guarantee of COM
potency. All the furnaces in Eureka,
with the exception of two water.jack.
cts at the Richmond, are notifications
of the Raschette and Piltz furnaces,
altered and improved to suit the COM
binations and qualities of tie ore
smelted. They are built OF stone from
the quarries in the. vicinity, and lined
with IA porous fire-prOof sandstone Of
excellent quality from Pancake mount
ain, about twenty miles distant. The
inside diameter will average AZ feet
at the hearth, and the height to the
charging windows is about l6 feet.
The hearth rises about 2H feet from the
ground and projects Is inches from
the mouth in the front OF the furnace.
On three sides, and n DOT above the
hearth, eight tweers pierce the shaft.
three on each side and two at the back.
The shaft is carried through the floor
and the charging windows open on the
second story, or ore floor, of the works,
but the masonry extends to and
through the roof, connecting with the
f1ue, or fume arrester. The tweers are
double wrought iron pipes, a space in
%tervening between the outer and inner
pipe through which a constant current
of water flows, preventing the melting
of the tweers where they are exposed
t O the fierce heat. The blast is fur
nished by a Root blower, with a ca
pacity Of 600 revolutions per minute,
and is conveyed to the tweers by a
system of tin pipes and n hose.
The front of the furnace is open to a
height Of ten inches, the space between
the melted Stag and masonry being
temporarily filled with a mixture OF
ire.proof clay, and removed at the
pleasure of the smelter, when 1t be-
comes necessary to ''bar out" or re-
move the Stag. At the side is the lead
well, connected by a pipe with the bot
tom of the furnace, the lead rising to
the same height in the well that it at.
tains in the furnace. The projecting
hearth is supplied with two spouts,
through which the iron and Stag are
drawn off into the cast-iron Stag pots.
In the working process the furnace is
a certain proportion of charcoal.
Fire is applied, the blast turn
ed on, and the furnace is in oper-
alton. The ore smelted is argentifer-
Gus galena, and contains from forty to
sixty per cent. lead, some iron, sui
phur and arsenic. The heat concen-
trated on the ore at the mouth of the
tweers will reach 1000 degrees Farm
heit, and under its influence tie met
ais contained in the ore and the silica
quartz, melt and flow to the bot
tom of the furnace. The lead, from its
greater gravity, goes to the bottom,
carrying with 1t the precious gold and
silver. On the top OF the lead the
melted iron floats, and on this again
swim the lighter materials, termed
Stag. AS the lead accumulates it is
ladled out from the we'll into molds,
forming base bullion bars, averaging
100 pounds in weight. These bars
will assay from two to four hundred
dollars per ton, varying with the
quality of the ore smelted. Each
charge is composed of SO shovelfuls
of ore, intermixed with II bushels
of charcoal. No hux is necessary,
with the exception of a shovelful of
silica or Stag, as the ores smelt free
ly. One OF the furnaces at the Eu-
reka Consolidated, now running, was
built for a reduction capacity OF so
IONS per day, but it goes considerably
above this, averaging IS tons every "a
hours, and has reduced as high as 80
tons, producing 10 tons of bullion.
The working force consists of one
smelter, two Stag wheelers, two feed
ers, and three ore and charcoal tenders.
The smelters receive five dollars per
day of eight hours, and the feeders and
wheelers four. The work is rather un.
healthy-thOse most exposed to the
fumes being subject to lead paralysis;
but of late the attention paid to venti-
lation has remedied this to a great de-
gree.
AS we stated in the commencement
of this article, there is no place in the
world where smelling has attained a
higher degree of perfection, and we are
constantly improving Il methods
and processes.