IMPROVEMENTS IN ATMOSPHERIC RAILWAYS
Year: 1860

page_text: PROVISIONAL SPECIFICATION left by Charles Stevens at the Office of
the Commissioners of Patents, with his Petition, on the 9th October
1860. A communication from abroad by V. Clovis Simboiselle, of
42, Rue Laffite, Paris, in the Empire of France.
I, CHARLES STEVENS, Manager of the British & Foreign Office for Patents,
1B, Welbeck Street, Cavendish Square, in the County of Middlesex, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN ATMOSPHERIC
RAILWAYS," (& that it has been communicated to me from abroad by V. Clovis
Simboiselle, of 42, Rue Laffite, Paris, in the Empire of France), to be as
follows:-
The improvements consist,―
1st, in causing the operation of rarefaction to be accomplished by the con-
ducting tube, which runs the whole length of the road, instead of by the
propelling tube, as in the railways hitherto constructed, as in that of Saint
Germain, which necessitates a powerful fixed engine at certain distances, on
account of the entrance of the air, especially by the longitudinal valve. The
conducting tube is sunk to a depth of about 3 feet the whole length of the
road; it is made of sheet iron, and communicates with the propelling tube
every 10,900 yards. This tube is covered with bituminous mastic, as is done
with gas pipes, and is arranged in the same manner. In certain cases, such
as crossing a river, the tube would necessarily be uncovered.

page_text: 2nd, the propelling tube and longitudinal valve. The propelling tube, as in
that of the St. Germain railroad, is made of cast iron, strengthened by large
hoops or binders boxing in one another. It is placed in the centre of the road
between the rails, so as to be perfectly parallel to them, and so that the upper
part of the tube is about an inch above their level. To prevent the entrance
of the air as much as possible, a thin sheet of india-rubber is introduced
between the two leathers of the valve. The surface of the free edge of the
valve, and that of the tube on which it rests not being perfectly adherent, the
air also enters in this manner, and thus introduces itself into the tube. This
is prevented in the present system as follows:-The longitudinal valve is com-
posed of a number of long thick leather bands, separated by a thin sheet of
india-rubber, and receiving above and below small plates of iron, and fitting
perfectly in the conical opening of the propelling tube. One of the edges of
this valve is strongly pressed along the tube, by means of a cylindrical iron
rod serving as binge, and the other rests freely in a gorge arranged the whole
length of the tube.. Levers three feet in length are bolted at a distance of
three feet apart on the appendices. of the propelling tube. The circular
appendices form every 20 inches cylindrical cavities of little depth. They
receive a small disk terminated by a rod receiving two screws, one of which
presses two thin sheets of india-rubber & leather on the lower part of the disk
and closing perfectly the orifice of the cylinder. This rod has a rectangular
piece of iron held to it by means of the second screw. Lastly, a small groove
goes from the cylinder into the interior of the propelling tube, and the sheets
of india-rubber & leather are strongly cemented together. Supposing, now,
the air in the propelling tube in a proper state of rarefication since the small
cylinders are in communication with it, the disk obeying the atmospheric
pressure acts upon the levers above mentioned, by means of small rods a
pressure equal to that received, thus hermetically closing the valve by
pressure.
3rd, communication between the propelling and conducting tubes. On the
arrival of the train the communicating opening must be closed, in order to pre-
vent the entrance of air into the conducting tube; this is effected as follows:-
The first carriage passes on a lever, which acts on a small piston, causing the
lower part of a cylinder to communicate with the. conducting tube. The
rarefaction is produced instantaneously, and the piston obeying the atmospheric
pressure descends in the lower part of the cylinder, & stops the communication
before the arrival of the train.
4th, the rails employed are those denominated single T-rails, fixed by

page_text: cramps to wooden sleepers. Every five yards cross pieces of iron bent so as to
pass beneath the propelling tube unite the sleepers, in order to maintain the
rails parallel to each other. The rails are each 5 yards in length, and are
fixed in the centre of the longitudinal pieces. The conducting tubes are con-
nected with pneumatic pumps at certain distances on the line. These pumps
are adapted to the situation in which they are placed, and may be worked by
steam or other power.