New-York tribune., 1870-11-22
HISTORY OF THE GREAT WORK.


CIPLE-A JOURNEY THROUGH THE VASE
BoRE-BLAsTING AND DRiLLING-ACCrDENTs
AND neutrality-suspicious. OF THE
ENTERPRISE IN DECEMBER-ITs PERFECT
SUCCESS.
As the great work of the Mont Gents Tunnel
Is TO DO completed next month, account OF its begin
ming and progress with OF the difficulties and OBJ
staces in the way OF it, continuance, can hardly he
without aptitude and interest The Mont Cents Tunnel
has been talked Of for nearly quarter OF century, and
I'm that time frequently forgotten and recalled by the
public press Europe and In this country that II Is very
questionable IL any great number OF persons have any
notion OF the condition prospects OF the work. This,
too spite Of the effort Of not few Imaginative Jour
nallss to keep up interest in the subject by printing
marvellous OF the discovery of an nexhaustbe
treasure of gems during the process OF excavation
DISCUSSION THE SUBJECT.
For four or ve years after the Tunnel determined
on the matter discussed again and again by the
Italian Parliament and press and all kinds OF theories
especially OF the adverse SORT advanced in the most en-
ergetlcay stupid manner. great many men who
claimed TO be supremely scientc-there Is smpeton
80 genuine as scientific simpletonmade 1t clear to
themselves the Tunnel could not by possibility
he made. They ransacked their imagination for formi
dabe gbears, and revealed capacity for suggesting
the unknown and terrible which proved their intellectual
right to countrymen OF Dante. 1t was grayey
predicted that all the workmen who engaged in the un
dertakng would perish by fire. water and noxous gases
that all the elements In word, would conspire against
the audacy and folly OF the enterprise. After these
victims OF ingenious fancy had demonstrated that was
entirely useless to attempt the work. the work was be-
gun In serious earnest and has gone on steadily ever
since The obstacles though great and almost countless
have been altogether OF different nature from those
that were prOphesicd.
Ihaye never been able 10 understand why the OF
Mont Cents should be attached to the famous Tunnel
since that mountain is II IS miles from the French en-
frnpa Tho
entrance Bardoneche. The Tunnel passes under three
peaks called the Col Freus the Grand valon, and the
Col de la Roue; the first being on the French the third
the Italian slope, and the second almost equidstant
between the two. Mont Cents enjoys the honor OF the
Tunnels baptism, presume, from the fact that 1t is
much better known than any OF the SUBMITS or ranges
in the neghborhood; and, moreover, it simplifes mat
ters to give the Tunnel which does not belong to
IT, rather than call 1t after any OF the three de-
serving OF equal distinction.
now TO REACH THE TUNNEL
The most direct way the Tunnel from the French side
4. to 90 by rail TO st. Michel wretched little savoyard
village which one likely to forget, particularly II
obliged stay night at the Hotel de PUnon where
everything is b0untfuy supplied but cleanliness com
fort and cOnv enience From St. Michel you compelled
either to walk ride in some rustic conveyance to
Fonrneaux distance of about eight miles which seems
sixteen before you arrive at your destination. Four
neauI miserable hamlet in narrow gorge in the val
ley OF the Are th inhabitantsof which are chiefly re-
markabe deformty and idocy Of the most repulsye
sort Grand valon Is II feet above the sealeve
crowned with while its sides covered with
and pines which look almost black under cloudy
sky. All about the valley Alps rise Alps, and seem TO
shut 1t in from the world. The scenery Is grand
and imposing and like most of that inayoy and swltz
erlsnd in marked contrast with the forbiddng not to
say revolving appearance OF the native population.
The work actually begun the Italian side IN
1851 and continued for four years, when, about 1000
yards having completed the perforaors called
into requision The common mode Of tunneling is to
vertical wells at proper distances and work through
from the other; but this not practicable in
the Cents enterprise 40 so years would have
been necessary 10 have made the wells sufficiently deep
The only feasible plan to begin boring at the oppo-
site ends and the difficulty then was supply air to the
workmen at distance OF two three miles from the
outer entrance. The ordinary motive power, steaH
needs fire for its generation, and fire needs air for it's
support Consequently steam could not be used; and,
after long delberation and countless experiments
pressed air was employed. The perforatlng machine
that has wrought tho Tunnel is moved
by common air compressed to One-sixth its
natural bulk which when liberated exercises expan
sve force equal to that Of six atmospheres The ma
chine composed OF Is upright iron tubes in which,
by yibraOry motion caused by the rise and fall Of water
and regulated by pisons in the tubes, the air. have
said Is compressed SIXTH AS the piston ascends 1t
forces the water up COMPRISING the air and driving 1t
into reservoir. As the piston descends valve is
opened the top andi through the valve the air
rushesnto the vacuum is in turn compressed and also
forced into the reservoir. From the reservoir large
iron pipe, rendered arght. conveys the compressed
air into the Tunnel. Ten OF the perforaors are kept
constantly at work. The drills working by the com
pressed air. keep steadily boring the rock at the
age rate Of nine feet day.
CHOICE OF THR LOCATION.
During the surveys preceding the selection OF the spot
for the Tunnel II discovered that the Rivers Arc and
Dora IN their wndngs at @ certain point less than
eight miles apart, and at this point it evident
Nature designed the great work should be constructed
The mouth OF the Tunnel $50 feet abov the level OF the
valley necessary from the fact that the valleys Of
the Arc and the Dora different nights above the
seaeve The inequality is regulated by grades 80 that
entering at Fourneaux the lower side, you come
Bardoneche at the proper level.
ADMISSION.
For some time after the Tunnel was begun, any and all
visitors admitted; but the work advanced, IL
became necessary to adopt stricter Permission
given to inspect the Tunnel two fixed days OF the
months and If any person Of influence position parcu
larly journalist wished TO examine the work at any
time, he had little difficulty In doing So When you had
obtained permission, you taken in charge by the
director OF the workmeD who gives you long india
rubber coat and lighted lamp attached TO half yard
of wire, and with these you set out upon your
sUBTERRASEAS JOURNEY.
The entrance is about as feet wide aud as many In
hight. double railway track runsjinto the Tunnel car
rying In the various implements and the stone for the
mason work, and bringing out the fragments OF broken
ana blasted rock At each side Of the Tunnel Is narrow
Sidewalk of nagstones. and the air conduit is ranged
along the side OF the gallery while between the lines OF
rails IN deep trench, the gas water pipes The
Tunnel as may be supposed is very damp, and number
OF little streams percoae through the rocky sides and
roof temporary wooden partition divides the Tunnel
INTO Two equal galleries, above and below; the rarcd