The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1856-1888, 1864-11-26
PACIFIC
Commercial Advertiser.
The Pneumatic Railway.

The Pneumatic Railway.
The LOGdOn Tunes contains an account Of the
Pneumatic Railway, recently constructed on the
Crystal Palace grounds, under the superInten-
dence Of Mr.. Rammeil, &. E., on which a series
of interesting trial trips took place ON 9th Sept,
with perfect success, In the presence OF several
engineers and scientific men. The following ex-
trac, will give a good idea Of this novel invention
A brick work tunnel, about loft. high by gift.
wide, and 600 yards long, and capable OF admit
ting the largest carriages used on the Great West
eTn Railway has been laid with q single line Of
rails, fitted with opening and closing valves at
either extremity, and supplied with all the other
requisite apparatus for PropellLng passenger trains
on the pneumatic principle. The object of lay
ing down this experimental line Is 10 afford, both
20 the scientific world and the travelling public, q
practical demonstration of the applicability to
passenger traffic Of the motive power already
employed by the Pneumatic Dispatch Company
in the conveyance of letters and parcels. The
pneumatic principle Of propulsion Is very simple.
The motion il throughout smooth, easy, and
agreeable, and the stoppages are effected gently
and gradually. Indeed, when 1t is considered
that the curve in the tunnel is unusually sharp,
being Of eight chains radius, and that the gradi-
eats are az high as l in 10, it is surprising that
the motion should be so much steadier and pleas
anter than ordinary railway travelling. The
journey Of GOO yards was performed either way
an about so seconds with an atmospheric pressure
OF only q ounces to the square inch but Il
higher rate Of speed, if desirable, CAD easily be
obtained consistently with safety The train
used on the trial consisted of one very long,
roomy. and comfortable carriage, resembling an
elongated omnibus, and capable OF ~ommoda
ing some 30 to IS passengers. Passengers enter
this carriage ut either end, and the entrances are
closed with sliding glass doors Fixed behind
the carriage there il a framework Of the same
form. and nearly the same dimensions, as the
sectional area Of the tunnel and attached to the
outer edge of this frame is IL fringe OF bristles
forming Il thick brush. As the carriage moves
along through the tunnel the brush comes into
close contact with the arched brickwOrk, go as to
prevent the escape of the air With this elastic
collar round it, the carriage forms a close fitting
piston, against which the propulsive force is di-
rected. The motive power is supplied in this
way AT the departure station a large fan
wheel, with an iron disc, concave IN surface and
% feet in diameter, is made to revolve by the aid
of a email stationary engine at such speed as may
be required, the pressure of the air increasing,
Of course. according to the rapidity OF the revo-
buttons, and thus generating the force necessary
to send the heavy carriage up u sleeper incline
than is to be found upon any existing railway.
The disc gyrates in an iron case resembling that
of a huge paddlewheel and from its broad peri
phery the particles of air stream off in strong
currents. When driving the air into the upper
end of the tunnel to prOpel the dOwntrain fresh
quantities rush to the surface of the disc to sup
ply the partial vacuum thus created and, on the
other hand, when the disc is exhausting the air
IN the tunnel with the view of drawing back the
~up-train, the air rushes out like an artificial hur-
ricane from the escape valves of the disc case,
making the adjacent trees shake like reeds and
almost blowing off his feet any incautiOus specta- |
tor who approaches too near it.
hen the down journey is to be performed the
breaks are taken of the wheels, and the carriage
moves by its own momentum into the mouth of
the tube, passing in its course over a deep air
well in the floor, covered with an iron grating.
Up this opening a gust of wind is sent by the
disc, when a valve, formed by a pair of iron
doors, hung like lock gates, Immediately closes
firmly over the entrance of the tunnel, confirming
the increasing atmospheric pressure between the
valve and the rear of the carriage. The force
being thus brought to bear upon the end of the
train, the latter, shut up within the tube, glides
smoothly along towards its destination, the re-
yolying disc keeping up the motive power until it
reaches the steep incline, whence its own momen-
tun again sufhces to carry 1t the rest OF the dis
lance. The return journey, as above indicated.
is effected by the aid of the e1hausting process.
At a given siynal a valve ~ opened, and the disc
wheel set to work in withdrawing the air from
the tube. Near the upper end of the tube there
II q large aperture, OF sIde-vault, which forms
the throat through which the air is, so to speak,
exhaled, the iron doors at the upper terminus
still being kept shut. In a second or two the
train posted at the lower terminus, yielding to
the exhausting process going on in its front, and
urged by the ordinary pressure of the atmosphere
from behind moves of on its upward journey,
tno rap;di1 ascending the Incline approaches the
ron gates- which fly open to receive it, and it
energies iss once into daylight. Such is the mode
in wBEHe the system works, and it seems capable
to railway communication with
metropolis and other large towns, or
Va, ser tunelled lines with steep gradients exist.
For thief obstacles encountered in practically
the atmospheric railway, introduced
P(l5 years ago, are considered 10 have been
= tually overcome by the present modification
he principle. 1t need hardly be added that
he worst drawbacks to travelling through tun-
the smoke and sulphurous vapors
emitted from the locomotive and tie close, I'M
wholesome atmosphere of the tunnels themselves
are in this case got rid of. Every train, in
carries its own supply of fresh air along
it, and also eIpels the foul dir before it.