The Ravalli Republican. [volume] (Stevensville, Mont.) 1894-1899, 1895-09-04
GIBBONSVILLE NOTES.
Our Special Correspondent Sends U
Another Ncwsy Letter.
G1BBoNsv1LLE, Aug. 2

plOfC tt4Ad pCOplC A1c oOll1 pOlA NY lu3
and q great many OF them are secur-
ing work. Many new buildings are
going up, most Of them shacks,
though there are some very good
ones. The building would be much
brisker if lumber we're more plenti-
full, but in spite Of the four sawmills
now running lumber is still scarce.
The new quartz mill started up
last week and is now running full
blast. Judges Of such matters say
it is a credit to the man who designed
it, and as good mill Of it's size as
can be found in the world. 1t is
certainly beautifully arranged af-
fair. 1t is built at the foot of a
steep hillside, and runs W on the
hill. Ore from the mines is hauled
in wagons into the upper story and
dumped through hole in the floor
into the receiving bin. From there
it passes down a chute into the
crusher, which is pair Of large iron
jaws that chew about as fast as q
sheep. 1t drops into a circular screen,
the holes in which are about half an
inch in diameter, and anything small
enough to go Through them drops
into the next bin, and what is too
coarse goes through chute to the
Cornish rolls, which consist Of two
huge iron rollers which slowly re-
yolye against each other and crush
whatever may come between them,
after which the ore drops into the
bin with that which went through
the screen.
Next comes the noisy part Of the
work. just below the bin are the
stamps, huge pieces OF iron weighing
$50 pounds apiece and each one drop
ping eight inches into another piece
Of iron at the rate Of 90 times min
ute. There are thirty Of these
stamps. In front and behind are
screens so fine that common salt
would not begin to go through them.
So far the rock has been worked all
dry, but when it strikes the stamps
water is added and falls, splashing
the water and whatever rock may be
fine enough through the screens.
The pulp, as it is now called, then
passes over large copper plate coated
with quicksilver which catches all
the face gold. When the quicksilver
is loaded with gold it is scraped off
and retorted; and the precious metal
is sent to the bank or mint.
But the process does not end here.
After: the pulp passes the plates it
goes into the hydromatic sizes, which
resemble large galvanized iron fumes.
These distribute the pulp to the
Frue yanners, OF which there arc
fifteen. These Frue Vanners are
nothing but immense rubber belts
about four feet wide with raised
rims along the edge: They run on
horizontal rollers which revolyc sc
slowly that the motion is hardly
perceptible. One end of this belt which
practically forms a table, is raised
enough to give Slight fall
SO that the pulp will run off at the
lower end. About two feet from the
upper end the pulp flows On from a
box which distributes it evenly clear
across. At this point the pulp re-
sembles skim milk more than any.
thing else. 1t runs down the sur.
face of the vanner and flows off in 4
stream at the lower end, the rollers
all the time carrying the belt in the
opposite direction. So nicely ad.
justed are these machines, both in
fall and in motion, that all the
heavy mineral-bearing sinks to the
bottom and clings to the surface of
the belt while the lighter waste is
carried off by the flow Of water.
About two feet fromJthe upper end
are a number of little metal spouts,
each of which pours tiny stream Of
water on the table and washes away
waste Which may be mixed with the
mineral clinging there. On the un-
der side OF the table is a tank Of
water which washes the concentrates
from the belt. So cleanly are the
concentrates separated from the
wastes that water thrown on them
will flow away as clear as before.
The concentrates, even after the
free gold has been extracted from
them, represent value Of about 5000
per ton.
The concentrates now go to the
chlorination plant, where they are
roasted and otherwise treated. This
department Of the mill is not yet
finished, but large force of masons
and carpenters is at work, and it is
expected to be running in about six
weeks,