New-York tribune., 1900-08-12

main ones These openings viii be closed with
doors. all except that which at any particular
time happens 20 be the one furthest in It win
then be possible. by forcing air in through one
tunnel and allowing it to return through the
other. to establish. a fine circulation. For that
PORTION Of the heading which is beyond the last
I door a supply OF air viii be furnished through
1O-inch pipe by hydraulic blowers. The air
will be artifciany cooled by a water spray be-
fore being pumped into the tunnel Already
this system is in operation at the southern, OF
Italian. end. but for the present different plan
has been employed at the northern end
When a tunnel Of this kind has been finished
:. slowly cooIs off inside. The temperature at
the middle Of the Mont Cents tunnel is now
about &C or s. degrees Fahrenheit. and in the
ST. Gothard tunnel between y and "a erd Il
remains substantially stationary the year
round. A ike improvement may be expected to
occur in the Simplon tunnel but more speedily
| than in the other instances, on account Of the
plan just described.
| Still, even after the heat has been disposed Or
other evils have been experienced in the past
1t has been deemed too costly to cut vertical
shafts from the tunnel to the upper air for
ventilatiEg purposes Accordingly. there has
| been a distressing accumulation of smoke and
foul gases from the locomotives. The products
| Of combustion are imprisoned near the middle
OF the tunnel, because there is an up grade from
each end to promote drainage. There IS a tun-
mel in the Apennines, between Bologna and Flor
| ence in which for long time passengers and
| trainmen suffered greatly from this cause On
one occasion, when one Of the crowned heads
Of Europe was riding through this tunnel the
engineer and fireman both became unconscious.
At length an engineer Of Bologna Signor Sac
cardo, proposed to try big ventilatlng fan at
I one end of the Fevt-
he reduced the temperature y degrees and
expelled the smoke and vapOr Since this
gratifying result was attained The system has
been installed at two other places in Italy and
in the st. GotLard tunnel. Preparations are now
being made for its introduction TO the Mont
Cents tunnel
There are now three great engineering works
Of this character in the APPS The Mont Gems
tunnel, begun in 1877 and finished in 1870 3
eight miles long and cost $1J.OJ3UyO It runs
from France into Italy, near d straight line
drawn from Lyons 10 Turin. The St Gothard
tunnel. 9.3 miles long. was started in 1870 and
completed ten years Iacer. It was designed C
open ur short route from Bavaria TO Lon
hardy. 1t is situated in Southern Switzerland
and emerges into a -eg51n that lies between
Lakes Masgjore and Como. The Arlberg tunnel
Les entirely II the Austrian TyroI and is only
four miles long. 1t was begun in ISs0 and fin
ished in 1884
The SimUlOn tunnel is meant to shorten the
route from Paris to Milan fOrty-eight miles
Its projected path is I22S miles long and
crosses from Switzerland into Italy about thirty
five miles TO the southwest Of st. Gothard and
scant one hundred miles in a beeIine east u
Geneva The northern terminus is the viIIs ge
Of Brieg. at the head Of the Rhone. The soulh-
ern end Will be near Iseu on a tributary Of the
TOce which empties into Lake Magg:ore on the
west The contractors are to receive about
Sl2OO0OOO in payment, although this amount
Will be varied by forfeits for failure to COM
plete or premiums for completion in advance cf
the stipulated time. The contract calls for do
ing the work in five and half years. and over
eighteen months Of the time have now elaDssL
THE JUBILEE OF "LOHEyGRIy"