IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES AND IN THE MECHANISM OR APPARATUS EMPLOYED THEREFOR, THE SAME BEING APPLICABLE FOR LIGHTING TRAMWAY CARS, SHIPS, FACTORIES, AND OTHER BUILDINGS
Year: 1876

page_text: LETTERS PATENT to David Laidlaw, of Glasgow, in the County of Lanark,
North Britain, Gas Engineer, for the Invention of "IMPROVEMENTS IN
LIGHTING RAILWAY CARRIAGES AND IN THE MECHANISM OR APPARATUS
EMPLOYED THEREFOR, THE SAME BEING APPLICABLE FOR LIGHTING TRAMWAY
CARS, SHIPS, FACTORIES, AND OTHER BUILDINGS."
ealed the 19th April 1876, and dated the 2nd February 1876.
PROVISIONAL SPECIFICATION left by the said David Laidlaw at the Office
of the Commissioners of Patents on the 2nd February 1876.
DAVID LAIDLAW, of Glasgow, in the County of Lanark, North Britain, Gas
Engineer. IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES AND IN THE
MECHANISM OR APPARATUS EMPLOYED THEREFOR, THE SAME BEING APPLICABLE FOR
LIGHTING TRAMWAY CARS, SHIPS, FACTORIES, AND OTHER BUILDINGS."
This Invention, which relates to improvements in lighting and in the machinery
or apparatus employed therefor, is more especially adapted to the lighting of
railway carriages, but it may also be used for lighting tramway cars, steam and
sailing ships, factories, and other buildings.
The Invention essentially consists in an improvement in that class of apparatus
commonly known as "air gas" apparatus, that is to say, in which atmospheric air
is converted into illuminating gas by passing it through a vessel or vessels
containing a volatile hydrocarbon, such as gasoline.
As applied to railway carriages the apparatus consists of an air pump driven by
means of a tangent screw and worm wheel from one of the axles of a railway
carriage, by which a current of air is driven into an elastic or bellows-like reservoir,
one or more of which reservoirs may be arranged beneath the seats of the railway
carriage, or a van containing one such reservoir of larger capacity may be used.
The reservoir is acted upon by weights or springs so as to produce at all times a
constant pressure on the contained air, and thereby cause it to flow out therefrom
into the carburetter in a constant steady stream. By means of the flexible reservoir
the shocks due to the shaking motion of the carriage and the pulsations of the air.
pump are absorbed, and the pressure of the weights or springs thereon causing the
Dis 0.77

page_text: constant flow of air herein-before referred to produces a steady flame at the burners,
through which the carburetted air escapes from the carburetter. The carburetters
may be arranged beneath the seat of the railway carriages, but they are, by
preference, placed in one or more of the vans.
The same apparatus may be used for lighting steam or sailing ships, tramway
cars, factories, and other buildings, and in any case where power is conveniently
situated for driving the air pumps.
In place of the flexible or bellows-like air holder herein-before described, a holder
constructed after the manner of an ordinary gas holder with a water tank may be
used.
In the case of conveying the gas from carriage to carriage in trains the pipes
forming the gas connexion between the carriages are fitted with water lutes instead
of screw or analogous couplings.
In case of any emergency by which a train is caused to stand so that the supply
of air is not kept up, one or more hand pumps is fitted on the train, by working
which the supply is kept up until the train is re-started.