The Idaho Springs siftings-news., 1907-08-31
ORE IN SHAkOBORE
FIRST REPUBLICAN, FINDS
ORE IN ITS CROSS-CU7
TUNNEL AS THE LATTER
NEARS A LODE.

A strike OF streak of ore last week in
the Shake tunnel on Mill creek, being
driven by the recently organized FIRST
Republican Mining company, of which
A. NJ. Kearns. q we'll known Denver bus.
ness man is the active head, has served
to again attract attention to that big en-.
Merprise, and the mining man of this
DPaper several days later paid visit to
that properly for the purpose of making
an inspection of the actual conditions.
The Shake tunnel is a cross cut being
driven by contract. The heading is
already in over 500 feet and at a depth of
over 400 feet below the surface of the
mountain side. and Is attaining a greater
depth with every foot the tunnel is ex-
tended. The course of the tunnel is
southwesterly and i, is destined to cut at
right angles all of the nine veins in the
group. The fact that pay ore has been
found and shipped from several Of the
surface shafts nearby. none of which
have reached a greater depth than 100
feet because of the inflow of water and
lack of hosting appliances. adds greatly
to the value of the enterprise, and places
it far in advance of the average mining
proposition, regardless of the additional
safeguards which are included in the
plans of the company.
The streak of ore opened IN the breast
of the Shake tunnel last week is un-
doubtedly what is termed feeder to the
L. s.,
more feet ahead of the breast. called the
Nero. No more favorable occurrence
than the finding of this feeder prior TO
reaching the vein could have taken place,
for it is these feeders which make the ore
bodies in 6ssure veins. An assay of the
streak showed 7 ounces in silver, which
together with the copper and zinc, gives
value Of little less than $40 per ton.
The striuger has a width of from two to
seven inches, aud will probably get
larger as the tunnel is advanced. Its
altitude at the portal of the Shake tun-
mel is 9, l. 80 feet, SO that when the breast
of the tunnel passes the apex of the
mountain It will attain a vertical depth
As the veins all lie at varying (angles
they will be cut at a third or more OF
that depth below their surface outcrops,
20 that at the greatest depth the veins
will be quarter of a mile overhead in
the tunnel.
The tunnel method is the twentieth
century system of mining. By this
method when the veins of ore are reached
the miner points long drill holes up
ward into the ore bodies and with
masses of ore, and it falls into chutes
from which it is loaded into cars and
taken out to the tunnel mouth, all by
gravity. At the tunnel mouth can be
located a mill where the ore is fed first
into crusher and on to the other ma
chinery and separating devices all by
gravity at a small cost, and consequently
at profit.
Under the shaft method of mining the
miner drills his holes down into the
water .soked rock, pumps the water out
of the holes, greases his fuse and mafe
Dis charges of dynamite water proof,
1oosens the rock with dynsmite, goes
down into the shaft with a pick and
shovels the ore into q bucket, hoists 1t 10
the surface, sorts it by hand, puts 1t on
the plat from which it is shoveled by
teamster into ore wagons, hauled from
one to ten miles to a mill and shoveled
out of the wagon into the mill. Here
it is shoveled some more, and there is a
loss and expense every time that
shovel comes in contact with the ore.
Coal costing from 81 to $40 ton must
be hauled up the mountain sides to the
mine, as we'll as all other mining sup
plies, and before any extensive mining
can be done by the shaft method, an IN
vestueut Of thousands Of dollare 10 re-
quired for machinery.
All Of this expense 10 obviated by the
tunnel method, and there are today in
this county but few mines operating in
that old-fsshioned expensive way. The
shaft system was followed for over forty
yeass, and during that time the mines Of
this section yielded upwards Of hun
dred millions of dollars. Today there
are nearly twenty miles Of tunnels al
ready driven throughout the county, and
the tunnel era is still in its infancy.
A gasoline engine and blower have
been placed upon solid foundations at
the portal of the Shake tunnel, which
when in operation will greatly facilitate
the driving of the tunnel by insurihg
Aood ventilation. After the blasts have
been fred it il necessary to wait until the
powder smoke finds its way out. but