The Superior times. [volume] (Superior, Wis.) 1870-1912, 1871-01-21
THE MONT GEMS TUNNEL.


met, and with such familiarity as their
diverse languages will permit, congrat-
ulatlng each other on the completion
of their more than herculean labor.
The Alps have been crossed even
with great armies since the DAYS of
Hannibal, but the undertaking has
been one Of 40 little toll and some dan
ger. In 1905 the first Napoleon CON
structed road through the pass of
Mont Gents, which was at a moderate
elevation of some 5, 400, feet above the
level of the adjacent country This
was thirty miles long and eighteen feet
wide, and was built at cost of 7,OOO,-
900 francs. 1t served for many years
as the only highway between France and
Italy but within the last five years a
railway has been built over the
ridge, upon which steam engine of
peculiar construction slowly drags a
single car. The idea of piercing the
mountain, and gliding from one coun-
try to the other in a few minutes time,
was first preached about twenty years
ago, and, as a matter of course, was
ridiculed by that large class of persons
whose conception of what can be done
is formed entirely in accordance with
what they know has been done. AL
manner Of difficulties and obsta lies
were suggested, and declared to be in
superable; but the projectors believed
they could be overcnme. The Govern
ments of France and Italy were applied
to to lend their assistance for the ac-
complishment of this stupendous un
dertaking The feasibility of the work
was argued at length before the legis-
lative bodies of both these nations, and
the result was finally contract for the
work
The route chosen was, of course, the
shortest possible line through the vast
mountain range, as the altitude of the
peaks or the general ridge made no
! difference with the work. The old
! plan of sinking shafts from the top at
! intervals, and working from one to an
other was pronounced impracticabie
| from the start, and a continuous Dor
! ing from either end was determined
upon as the only method of proceeding,
the workmen being supplied with light
and air as they retreated from the
cheerful light of day and the whole
some atmosphere of the outer world
! The place was found about fifteen
miles from the old Mont Gents road,
where a tunnel of II, 900 metres, or a
| little less than eight miles in length,
would pierce the mountain range and
connect the town of Fourneaux, near
Modene, in the valley of the Arc, in
| Savoy, with Bardoneche, in the valley
of the Dorariperia, in Italy, by a rail
road over which a train of cars of any
desired length could run in a very few
minutes. Between these two te5mi,ai,
the tunnel passes under three noun
tains of considerable height even for
Alpine peaks, known as the Col Freius,
the Grand Vallon and the Col de la
Kone, ranged in the order in which
they are here named as we pass from
France to Italy. The central summit
is over II, 900 feet above the sea level,
and by the old method of sinkings hats
! it would have required more time and
| labor to bore one of these than has been
| taken for the entire work
| The work was begun in 1857 At
first the ordinary hand-drill was used
to pierce the rock, and the solid masses
were blasted out with powder. This
method of operating, which was kept
up on the italian side until 1861, and
on the French side until 1853, would
rhave required upward of fifty years for
the completion of the work. Accord
ingly it behooved the projectors to be
think them of some more expeditions
method of proceeding. The use of
steam was out of the question, and the
attention of the italian engineers was
! therefore turned to a device for using
| compressed air as the motive power
| This matter presented no very great
difficulty in it's general principles, but
great deal of experimenting was nee
essary before it could be put into sue
! cessful practice.
A machine was finally invented and
put into operation which could stand
outside by one of the streams that
came down from the mountains, and
with its aid force the air through long
tubes to the drilling apparatus. This
/ latter is machine which works in a
galley nine feet square, and carries a
large number of perforators, each of
which bOres a separate hole in the
rock. By the COMPRISING machine
the air is forced into a reservoir, and
thence it passes through flexible pipes
to the cylinders containing the drills of
the perforating machines. BY the
opening of a valve each drill is forced
against the face of the rock with force
of about 200 pounds, turned slightly,
and withdrawn. Two hundred of these
blows are given every minute with each
drill, and when holes of the required
depth have been bored, the air is turned
off. and the machine withdrawn
short distance. The holes are bored
in such a way as to converse slightly
toward each other, so that every blast
will bring down considerable mass of
rock. At first, powder was used in the
blasting, but there We're many obvious
objections to tins. AS soon as
any considerable progress had been
made, and subsequently grln-cotton
was tried. This was afterwards dis
placed by the use of itro-glycerine.
The rate of progress has varied. of
course, with the hardness of the rock,
and has been from one and half to
three feet per day Among the Incl
dental appliances employed by the
workmen. are gas-house, miniature
water-works, and machinery for sup
plying their own lungs with air as well
as those of the perforating machinery.
Thus the three essentials of comforta-
BILE Ife-light, air and water, are re-
ceived from the outer world by ma
chinerv.
The tunnel is in the form of a seq
ment of cylinder, the bottom being
level for the roadbed of the proposed
I, IL - Il. \ 4