New-York tribune., 1868-07-02
THE SUTRO TUNNEL

THE SUTR0 TUNNEL
The application of Adolph Sutro and his as
sociates in the SutrO Tunnel Company to Con-
gress for the loan of Government bonds to the
amount of $5OOO,OOO, to aid in boring tunnel
for draining and removing the ore from the
celebrated Comstock Lode in Nevada, calls for
a grant of novel character. We are opposed
TO aiding public or private enterprises of any
kind unless there are the most unequlyocal
proofs of the necessity, profit, and safety OF
doing so, and we have therefore examined this
project with every predispOsition to oppose 1t.
If our preudces have been reversed by IN
vestigation it is probable that the same facts
which have convinced us of the prOpriety of such
grant may convince others.
The ComstOck Lode is, gcOlogcally. fs-
sure vein Cor chasm created by a volcanic con
vulsion, rending the earths crust and filling the
rent by injection from below, filled with min
eral quartz bearing both gold and silver, in the
proportion of 81 in silver to II of gold. Ii APP
pears upon the surface for several hundred feet
in width and several miles in length, running
north and south, and dipping, at an angle of
As, to an indefinite depth. Upon this ledge,
some thirty or forty mining companies have
some of them to n depth of eight hundred
OF nine hundred feet, and within SIX
wears past over SS0,0O0,00O of gold and
silver bullion have been extracted, while
the present annual yield exceeds sl6,OO,WO.
But the best geoogists certify that the Com
stock il q larger and more regular and perna-
nent vein than either the great PotOsi mine OF
Bolivia. which yielded S1,2OOO 100000 the Veta
Madre of Guanajuato, SSOO00O,OOO, or the Veta
Grandc of Zacatecas, $3.50, 0OO-the two last
being the richest mines of Mexico. 1t is fair to
assume that the wealth OF the COmstock Lode
has only been tapped at the surface and yet
the shares of the mining companies are declln-
ing in value, the mines are upon the verge OF
suspending operations, and, if unasslsted by the
Government, must shortly reach the limit be-
yond which every dollar of ore extracted will
cost more than dollar to extract This is
because, first as the shafts descend, the cost OF
pumping up the water, expelllng the foul
vapors and raising the ORE increases IN almost
geometrical ratio; and secondly, the companies
working separately are each compelled to pay
for separate engines, works, fires, and to sus-
tain a separate set of wOrkmen and officers.
The expense of each company draining Its own
mine exceeds any consolidated system which
would drain all the mines, as in city the eX-
pense of each householder building his own
water-works, sewers, gas-works, &c, would
exceed the expense of having water, gas, and
sewerage, furnished by one source. These
expenses have so increased that the three
hundred tuns of gold and silver ex-
tracted last year. worth S16,OOO,0OO, were
mined at cost of S155OO,OOO, leaving only
sjOOOOO profit, which would be very mOder-
ate interest on the capital invested. Indeed,
careful computations show that the shafts can
not be sunk to a depth of 1900 feet without
increasing the cost of pumping to S5,OOOOOO
per annum, and that, long before this stage
should be reached, the works will have to be
wholly abandoned. Nor is the increase in ex-
pense the only objection to pumping. The
pumping works introduce into the mines q vast
quantity of woodwork and machinery, which
soon rots and wears out, and requires replacing.
Meanwhile, the mines are always heated, damp,
and dangerous to the lives OF the miners; while
any cessation in the exhaustng and proftess
labor of pumping fills up the mines and de-
stroys the results of the capital and labor pre-
viousy expended.
4 he OulIO ullncl IOlpdny pIupOscS W uIdlH
the mines, both of water and ore, by nearly
horizontal tunnel, seven miles long running
from the base of the mountain and striking
the lode at point 1000 feet below the sur
face, with side galleries so constructed as to
serve all the companies operating on the lode
The tunnel would be 12 feet in width and 10 in
hight, which would afford sufficient space for
railroad for ore each way and the stream of
water underneath, with descent of one inch
per hundred feet. The moment the tunnel is
complete, it drains and ventilates all the mines
perfectly by the force of gravity.
Such enterprises are familiar to the miners
of Europe. Little SaxOny has constructed more
than hundred miles of mining tunnel; Han
over nearly as much. Some of their tunnels
are nine or ten miles in length. The Sutro
Tunnel will pierce three or four considerable
lodes before striking the Comstock, and the
amount of mineral wealth which it will make
available is almost incaculable. 1t is reason
able to suppose that it will increase the pro-
duction of the Comstock lode alone to
$50 100000 year. From the great depth at
which it strikes the lode it will drain the
mines for a hundred years. The Tunnel Com
pany has obtained agreements from the pro-
prietors of all the mines to be drained for the