Gilpin observer., 1908-02-13
Record In Tunnel Driving.

A tunnel driving record was made
during the month of January in the
Mcclellan tunnel, says the Idaho
Springs correspondent of the Daily
Mining Record, when in thirty-one
shifts the heading was extended ZO3
feet nearer to the famous old Freeland
mine, making the length of the tun-
mel today 6,375 feet, and placing the
Mcclellan tunnel, except the New
house, the longest subway in this sec
ton of Colorado.
The record is an exceptional one be-
cause the work was accomplished with
a crew of sixteen men, and the further
fact that bar of the hardest, flint
like white spar ever found in the dis
trict was encountered last week, which
required two days of steady drilling to
get in the round Of holes ready for
blasting the first round that was lost
in the last four months of tunneling.
Eighty-four feet of this work was in
the hard ground. Had the ground re-
NAMED regular, at least 220 feet would
have been made in January. The rock
encountered was so hard, tough and
brittle that it was with the utmost
difficulty that the holes could be
drilled. The drills would pound away
with full force and make only snail
like progress in drilling, with every
few moments broken drill to be re-
placed. In drilling one round of holes
thirty-eight drills We're broken, some
of them in two and three places.
The achievement of this remarkable
record in tunnel driving is due to the
skill and Judgment of Foreman Will
liam II. Irvine, who has had years of
experience in that class of work.
The footage made during the past
month stands alone, in that under Mr..
Irvine the Mcclellan tunnel has been
driven further, with fewer men. than
has ever before been accomplished in
any tunnel in the district. The crew
engaged in drilling and breaking the
ground consists of three machine men
and two blasters, while the crew en-
gagged in removing the broken rock
consists OF five men. Two engineers,
blacksmith and helper, a trainman and
roustabout constitute the entire work
ing force.
Two of the new water Leyner model
No 6 machine drills are used for put
ting in twenty-eight-foot holes for each
round of blasting, the two machines
being set up in the breast side by side
and operated by three men.
While the Newhouse tunnel and
many others in this district are irreg-
ular in size, and with arched and
rounded roofs. the Mcclellan tunnel
has been driven over a mile of a uni
form size of nine by ten feet with
squared roof, and 1t is the most per
fectIy con st ri ri ed mining tunnpl of II <
length in the world. from an engineer
ing standpoint as well as in appear
ance and timbering.
The Mcclellan tunnel is now the
second longest tunnel in this section of
Colorado. having attained that distinc-
tion with the round of holes blasted on
New Years day, at which time II
passed the heading Of the Central tun-
mel being driven by the Big Five. on
January 1st. the Central tunnel was
GLIB feet in length. ore one foot longer
than the Mcclellan tunnel. During
the month just passed the Central tun-
mel was driven eighty feet and the
Mcclellan tunnel 203 feet, so that on
February |. 1908, the breast of the Nc
Clellan tunnel is just l22 feet further
into the mountains than the Central
tunnel.
The Mcclellan tunnel has been
driven a total of 1.27l feet since the
latter part of last May. while the Cen
tral tunnel has been driven but 905
feet during that time.
The Mcclellan tunnel heading Is
now well within the Freeland terri
tory, and in the next few months will
encounter the big Freeland vein. its
present objective point.