The Salt Lake tribune. [volume] (Salt Lake City, Utah) 1890-current, 1911-01-12
DEEPEST SHAT 7
IN THE WORLD
J. Parke Charming Recently
Had Occasion to Visit the
Tamarack.
COPPER DECREASES
AS DEPTH REACHED
Very Little Water Encountered
in Mining One Mile Be-
low Surface.

In the course OF some professional
work / have lust had an opportunity OF
going into what is probably the deepest
underground workings IN inc "otlo' II
Simplon tunnel, which, | believe. is some
5000 or 900e feet below the summit OF inc
Alps To the Tamsrack mine, now pracc-
ticaly n subsidiary Of the Calnmet y
Hecla Mining company. belongs the credit
of having the deepest shaft In the world
and the deepest underground workings
from which mineral Is being extracted
No. 5 shaft crosses the Calumet CON
glomerate at depth Of $500 feet. meas
ured from the collar OF the shaft ana
is now down To a depth Of o2IJ.5 feet, II
having at that depth cut the Osceoia
amygdaoid and passed through IL. 1t Is
interesting TO note that AT the upper por-
ton OF this lode considerable native cop
per was found. In short time this
farther. In the cutting out OF a sump'
thus making II over u mile In depth:
No. 3 shaft of the Tamarack has been
sunk TO a depth OF 5222 feet. The collar
OF this shaft. however. is thirty -one feet
higher than that OF No. 8. This No. 8
shaft crosses the Calumet conglomerate
at about $3.50 feet. Al the so-called
eighteenth level, a crosscut driven 500
feet 10 the west, reached the lode at
vertical depth Of 51Si feet, from which
point a slope has been sunk 300 feet to
the twenty-lirst level. below which there
is stump of seven feet The bottom OF
this incline is 1865 feet below the collar
OF No Tamarack shaft. measured verti-
cslIy. The Calumet conglomerate dips
at an angle OF approximately SS degrees
10 the west, so That, measured on the IN
cline. this point Is very nearly 5000 feet
from the outcrop. At this point the lode
looks fairly good. and is sufficiently rich
To warrant its extraction and treatment.
The longest inclined shaft in the Lake
Superior copper country is No. Calu-
ing company. which is down TO the
eighty-first level. this being approx
mately dist ance Of s100 feet along tho
slope, at an incline Of about 3S degrees.
AS showing the strong belief To the
persistence Of the various lodcs In Lake
Superior in depth. and the possibilities OF
extracting copper at prollt, the Quincy
Mining company has lately purchased. for
1000. from the Canal company, tract
OF land lying TO the west OF its own
property. and which will not be reached
by It's present workings until they are a
least 1000 feet In depth. measured on the
slope.
As has been previously published the
rate OF increase OF temperature in the
Lake Superior copper mines is not ex-
ccsslvc, the rock tempcratu at a depth
OF 5000 feet vertical being approximately
90 degrees f.. and II proper means Of
ventilation are used there Is no diff
Guilty In opera ting a this depth. II, how
ever. proper connections are not made the
air becomes excessively humid. thus ma
terially reducing the efficiency OF the
miners. The mechanical difficulties In
mining at these depths consist In the
necessity OF keeping the timber close 10
tho working faces because OF the great
pressure due 10 superintendent mass Of
rock. and the method Of mining now used
Is similar TO The long wall retreating
method OF the coal mines.
when IL comes 10 hoisting ropes il is
impossible 10 keep The same high factor
Of safety as in shallower mines. this fac
tor being often reduced TO 80. This
however. has led to no serious conse~
quences other than that OF some In
creased expense because Of the necessity
OF more frequent changing Of the ropes,
so as not 10 keep them too long in scrv-
ice
II is fortunate that in the Lake Su-
peror copper mines, after getting down
below the fractured surface zone. prac-
ucally no water Is found. On the lowest
levels OF the TamaracS mine the only
water visible Is n slight seepage. which
Us extremely bitter TO the taste. Analyses
oi the water made bv local geologists
nave shown the presence of chlorides and
hromidcs OF sodium and magnesium
There has been considerable discussion "A g
70 the origin of this water, some thinking
II Is the remnant Of pre- historic ocean
water and others believing THAT il Is the
water which deposited tho minerals Tfn-,..
ever. from practical point Of view, the
iact is mat these mines at tho docncsi
levels. make only little more water than
rs necessary for the Use of air drills No
pumps are installed in the mine and tho
httie excess OF water is bailcd out once
week. oftencr
lhere Is. OF course, a gradual decreasn
IN copper contents OF the rock as depth
Is attained, which has been made up for
by increased efficiency and improvod
methods. |; is fact in biology that no
organism develops beyond the needs of
It's Immediate environment, and II is plain
10 see that this same rule exists in min
ing.-J. Parkc Claiming in the Mining
and Scientific Press
Copper Exports.