Evening star., 1923-11-11
A Mountain of Gold.

SOME time ago the gigantic task
or burrowing into a mountain
nuik to mine millions of tons of gold
ore was completed In Alaska rbrse
mining companies undertook to omen
up the largest vein of gold in the
world. and when the stamps started
to drop. the biggest ore-crushine en-.
terprise OF all was under way.
It Is estimated that the life" of
this vein will approximate 100 years.
II everything goes as expected the
daily output of the three mines will
be In excess of $4,000 daily.
The Juneau gold belt lies in a pre-
clpitous mountain range. which rises
from the very waters edge Of south
eastern Alaska's great archipelago.
hunters used to scale the mountains
and hunt for bear. deer and mountain
sheep; and in winter, when the winds
from the glaciers come bowling up
the channel. soaring the whole coun-
tryside with frost. many a Iuckless
hunter has perished.
Into this dreary country. after the
discovery OF gold. engineers came and
started their work. But this noun
tain of ore near Juneau was not
thought rich enough to mine, and 40,
although conceived originally twen-
ty-hve years ago. when the success of
the famous Treadwell mine. two miles
from Juneau, astounded the mining
world, the plans for developing the
Juneau mines on the elaborate scale
mentioned did not assume definite
shape until about ten years ago.
The first step in the vast undertake
ing was the question of power. Four
miles north of Juneau q mountain
stream tumbles down from a per-
petual snow field. The engineers pro-
ceeded thither, hauled a mile or two
OF wooden pipe from the oceans edge,
Installed 1t. built a penstock and con-
structed makeshift power house at
the mouth Of the stream. In q few
months $500 horsepower was avail
able for construction work.
The work did not stop there, how
ever. More pipe was brought in. a
tramroad built from salt water to the
head. of the stream. a dam site laid
out and an immense concrete dam
started. This dam impounds enough
water to cover 10000 acres one foot
deep. and insures the operation of two
s.0o0-horsepower electric plants the
year round.
A tunnel nearly 10000 feet long
then was driven along the ledge of
gold-bearing ore. and such splendid
work was accomplished by tunnel en-
gineers that special recognition was
given the crew by the company. One
end Of the tunnel Is connected with
the surface by q perpendicular shaft
1874 feet deep. The ore from the
ledge is dropped to bins arranged
along the main tunnel. to be loaded
into self-dumping cars and carried
I1N miles to the mill by an electric
trolley system. The engineers are
planning other tunnels to parallel the
main tunnel and thus double or treble
| the output Of the mine.
Science has been called into play in
| the treatment of the ore after 1t
reaches the mill. Great iron jaws
crush the coarse ore to definite
regular fneness. The ore falls into
an underground bin and is carried by
| massive bucket line to a hne-crush-
| ing plant situated on the same hill
side q few hundred feet farther down.
There are two kinds of crushing
mechanism that effectually extract all
the free gold in the ore. Tables that
move back and forth with quick jerks
serve to concentrate the heavier par
ticles Of refuse that contain minerals.
This concentrate" 10 subjected to
chemical treatment and every grain
of gold in the ore is recovered. The
mining engineers of Alaska have ap-
piled to their work the motsa Of the
Chicago meat packers: Save all the
pig but the squeal." From the sand
that is carried out to sea by the tall
race of the mill, q miner could not
| obtain a particle of gold IL he sifted
| through a thousand tons Of the refuse.
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