The spirit of democracy. [volume] (Woodsfield, Ohio) 1844-1994, 1852-11-10
Foreign Correspondence al State Journal
AsUcCEssFUL ATMOSPHERIC RAIL-
WAY. N /,

chanical way. which r have met in my
travels, Is that Of the Atmospheric Rail-
way at St. German, about fifteen miles
from Paris. Atmospheric pressure has
here been adopted to propel trains of cars
for a distance Of FIVE miles and nearly
half-the last half Of which has an ascent
Of 81 per cent. The object in adopting
this system was to bring the terminus Of
the road up into the city Of ST. Germain
which is located on af,hill forming the
south bank OF the Seine. The ascent was
too great to be overcome in all weathers
by a locomotive. and indeed only one loco-
motive has been lound sufficiently power.
ful to draw a train up at any time. The
system in use in the United States on in
clined planes. of drawing trains up and
letting them down by means of a rope.
has been found here. as elsewhere, too
troublesome. too slow. aud attended with
too many accidents. to he found available
on suburban roads where the travel is so
great. 1t is so rare to meet with anything
in these old countries in advance of Amer
lea in real, practical utiliiy-in the inven;
tive genius which has an utilitarian end
that we have deemed a short description
of this most admirable and really inter
esting invention might prove acceptable
to your readers; most Of whom are by
! this time no doubt either directors, stock
holders or employers Of railroads. {.
Being fortunate enough TO have for a
! cicerone on this occasion. an American
lady. long resident in France, we were
enabled to obtain from the gentlemanly
superintendent, through the medium Of our
Interpreter, a full knowledge of the me.
! chanism and the operation Of this admi-
rsble machine. An iron tube is laid down
in the centre Of the track. which is sunk
about one.thir6 Of its diameter in the bed
of the road. For a distance Of about
$500 yards the tube has a diameter of
only Il feet, the ascent here being so slight
as not to require the same amount Of force
as is required on the steep grade ascend.
ing to ST. German. where the pipe for a
distance of $500 yards is 9 feet | inch in
diameter. The manner Of applying the
atmospheric pressure 10 the propulsion Of
the train is exceedingly simple. The air
is exhausted from the entire length OF the
tube. so as to produce a.perfect vacuum,
lust before the arrival Of each train, which
is every half hour, by means Of powerful
and beautiful engines, somewhat resemb.
ling those at Paramount. These engines
are placed, two of 200 horse power. at
St. German. and one each at the towns of
Nauterre and Chaton, in the valley towards
Paris. fo 3's0-H VI
To each engine is adapted two large
cylinders which exhaust fourteen cubic
feet of air per second. The pressure ir
the large air caldrons (chaudieres) attach
ed to the ~exhausting machines is equal to
six absolute atmospheres. 1t will be read.
lily understood that when this long tube is
completely exhausted Of air, if a piston so
nicely adjusted 10 the size Of the tube as
to render it alright, is allowed to 60 loose
at one end, it will rush through with great
velocity to the other end to fill up the vac
uum. To apply the motive power, there.
fore, to the propulsion Of the train it is
only necessary that this piston be attached
to the train Of cars in such a way as 10
drag them along after it.
This was the great difficulty to encoun.
ter; but so admirably and so simply was
this overcome that the engineer assured US
that an accident of any kind seldom ever
occurred. Throughout the entire length
OF the tube, a section is made in the top,
leaving an open space of about five inches.
In each cut edge of the section there is an
offset, to catch the edges Of a valve which
fits down upon it.
This valve is made of a piece Of sole
leather half an inch thick. having plates
of iron attached to it on both the upper
and corresponding under side TO give it
strength to resist the suction Of the vac.
uum, which are perhaps one-fourth of an
inch in thickness. They are not quite as
wide as the leather but wide enough 10
touch the offset in the section.
The plates are about nine inches long.
and their ends, above and below, are plac.
ed three quarters Of ar inch apart form.
ing joints, so as TO give the leather valve
pliability, and at the same time frmness,
10 resist me powerful atmospheric pres
sure which is brought to bear on it when
the air is exhausted, The entire length
Of the valve, from one end of the tube to
the other, Is attached 10 one side, like a
cellar door. for example. From the back
side Of the piston. a strong iron rod pas
ses up throughthe aperture. which is made
by raising up the edge Of the valve, and
is attached to the bottom of the foremost
car. As fast as the piston passes along.
the valve is released from pressure behind
it, the loose edge is liberated. and the bar
of iron which is attached TO the car a foot
or more behind the piston meets with no
obstruction to its passage. SO
The pressure Of the atmosphere on the
valve in front Of the piston, where the vac
uum still exists, is SO great. that there is
no danger of the bar OF iron exerting pres