AN IMPROVED COMBINATION AND ARRANGEMENT OF DEVICES 5CES FOR SUPPLYING THE TANKS AND
Year: 1872

page_text: LETTERS PATENT to William Edgar Prall, of the City of Washington,
in the District of Columbia, and United States of America, for the
Invention of "AN IMPROVED COMBINATION AND ARRANGEMENT OF DEVICES
5
COMPLETE SPECIFICATION filed by the said William Edgar Prall at
the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 15th November 1872, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDGAR PRALL, of the City of Washington, in the District of Columbia,
and United States of America, send greeting.
WHEREAS I am in possession of an Invention for "AN IMPROVED
COMBINATION AND ARRANGEMENT OF DEVICES FOR SUPPLYING THE TANKS AND

page_text: to grant unto me, my executors, administrators, and assigns, Her
Royal Letters Patent for the same, and have made solemn Declaration
that I am the true and first Inventor thereof.
NOW KNOW YE, that I, the said William Edgar Prall, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention,
and in what manner the same is to be performed, in and by the following
statement:
This Invention relates to the supplying of the water tanks of loco- 1
motives with water by the use of compressed air; and it consists in a
novel combination and arrangement of devices for that purpose, as will
be more fully explained hereafter.
In the accompanying Drawings forming a part of this Specification,
Figure 1 is an elevation of a locomotive and its tender, with a sectional 1
view of a water tank or reservoir sunken by the side of the track from
which the tender is to be supplied; and Figure 2 is a sectional view
of the tank of a locomotive tender arranged with separate spaces therein
for air and water.
The need of better appliances than those now in ordinary use for 2
supplying the tenders of locomotives with water has long been felt,
and acknowledged by many railroad officials and engineers. The means
usually employed for this purpose consist of an elevated tank or reservoir
placed at a sufficient height above the road to admit a flow of water
therefrom to the tender by gravitation, a pump to force water into said 2
tank, and an engine to drive the pump, a house to cover such tank to
protect it from the weather, and in cold climates the necessary appliances
for warming the tank house.
It is also well known that as a substitute for the above tanks have
been sunken in wells so that the water might naturally flow into and 3
fill them, the tanks being so constructed and arranged as that when the
train arrived a connection could be made with the boiler of the loco-
motive and steam admitted to the tank to drive the water therefrom
up through suitable pipes into the tender by the simple pressure of the

page_text: steam; but this plan has been found to be objectionable on account of
the rapid condensation of the steam in the cold tank.
My Invention has for its object the production of a cheap and reliable
means of producing the result last above-named, and which shall be free
from the objections which may be urged against the methods heretofore
tried or now in use.
In carrying out my Invention practically, one or more simple air
pumps, of any approved construction, are attached to each of the loco-
motives in ordinary use upon a railroad, the pump being located upon
the locomotive at such convenient point as to be either worked by some
one of the moving parts thereof or operated as an independent engine,
by steam derived from the boiler, and be made to compress air into a
suitable tank or receiver which shall thus be kept constantly filled,
so that upon the arrival of the train at any station the compressed air
may be used to force water from a supply tank up into the water tank
of the locomotive.
In the accompanying Drawing the dotted lines at A, Fig. 1, illus-
trate an air pump placed at a central point on the locomotive, so
as to be worked directly from the cross head X; but the pump may
likewise be placed under the foot board, and be worked by an eccentric
upon the driving wheel shaft; or in fact it may be located in any one
of several positions which will naturally suggest themselves to a skilled
mechanic, and constructed to be operated independently of the moving
parts of the locomotive proper by steam from the boiler.
The air pump A is connected by suitable pipes B with one or more
tanks or receivers O for the reception and retention of the air com-
pressed by the pump. Pipes B may be wholly or in part flexible.
The air tanks or receivers consist simply of air-tight chambers made
of metal sufficiently strong to resist a pressure of many atmospheres.
Where it is desired to preserve the general appearance of the loco-
motives and tenders now in use in applying my Invention thereto,
the air tanks may be located in the front ends of the arms of the water
tank upon the tender (as illustrated in the Drawing, Fig. 2, the air
chambers or receivers being designated by the letters O, C,) in which
case a pipe C¹ is made to extend from one to the other for the purpose
of equalizing at all times the pressure in the two chambers. It will

page_text: however, generally be found preferable to construct the air tanks or
receivers each in the form of a cylinder, and to suspend the same
underneath the frame of the tender or of the footboard of the loco-
motive, although it is manifest that they may be constructed of any
form and secured at any point upon the engine or tender which con-
venience and the requirements of any particular case may demand or
suggest. Or in fact they may be located upon any one of the carriages
of the train to be drawn by the locomotive.
The air receiver C is in all cases provided with the means of con-
necting thereto the pipe or hose B from the air pump, and with a
valve or cock for closing its induction aperture whenever it is necessary
to disconnect said pipe B. This valve may be opened and closed by a
rod D (see dotted lines Fig. 1) which passes up through the top of the
receiver or by other suitable devices. The receiver C is also fitted with
convenient devices for attaching or connecting thereto an eduction
pipe E to conduct the compressed air therefrom to the reservoir, which
contains a water supply, and also with a safety valve D¹ which serves to
prevent an undue pressure therein. This valve admits of adjustment
so that it may be made to confine the air up to any given pressure
which the receiver is strong enough to withstand, and when the desired
pressure is obtained to open automatically and allow any surplus of air
which may be forced into the tank to escape. The nozzle or other
device by means of which the eduction pipe E is connected to the
air receiver is provided with a suitable valve for closing its opening
when the pipe is detached therefrom. F in the Drawings represents
an air-tight tank of wood or metal sunken in the ground near to the
track of the railroad, and so arranged as that it shall be kept filled by a
stream of water flowing naturally thereinto from any convenient natural
or artifical source through a supply pipe H. This tank or reservoir
may be of any desired form, and in cold climates is buried deep enough
to keep its contents from freezing. The inner end of its supply pipe H
is provided with a simple valve which opens inwards so as to permit
water to flow therefrom into the tank, but which will be closed the
moment air is admitted to create a pressure within the tank. This
pipe H is dispensed with when the tank is immersed or submerged
in a well, pond, or stream, for in that case one or more simple openings
are formed in the walls thereof, these openings being fitted with valves

page_text: opening inward to prevent a reflow of the water entering through
them. G is a pipe of suitable diameter as required which is fitted
to the tank or reservoir F for the discharge of water therefrom. The
lower end of this discharge pipe extends within the reservoir F nearly
to the bottom thereof, and its upper end passing through the top of the
reservoir with an air-tight joint is carried up to a convenient height for
the reception of a flexible pipe G¹ to facilitate the discharge of the water
into the tank of the locomotive or tender.
The flexible pipe E, which leads from the air receiver O to the water
reservoir F, connects with a pipe or nozzle secured to and projecting
from the upper head or end of said reservoir, and when in use it may
be supported upon a post and projecting arm, as illustrated in the
Drawing, Figure 1.
The devices for conducting the air and water may be varied from
those described, and their arrangement manifestly changed to suit
varying conditions arising from the peculiarities of the location of
the water reservoir F, as well as for other reasons without departing
from my Invention.
By the use of this Invention the power for elevating the water may be
obtained at a mere nominal cost, either by connecting the air pump with
the moving parts of the locomotive so that it shall be driven thereby,
for in such case the compression of the air into the air receivers being
effected by the movements of the locomotive when running, may be
accomplished either when it is upon a descending grade or when it is
approaching a station, times at which there is a surplus of power which
ordinarily has to be neutralised by the application of brakes to the
wheels of the train, but which is thus in part utilised, or when the
pump is driven independently with steam from the boiler of the loco-
motive by working the pump when the locomotive is standing at a
station, thus utilising the surplus of steam which would otherwise
escape through the safety valve. Again, as the water reservoir may be
sunken below ground the expense of a tank house to protect it may
be thus avoided, and as it is self-filled the cost of an engine to draw and
force the water and of an attendant thereon is saved.
Having thus described my Invention fully, I claim therein as new,
the combination with each other and with a locomotive, as herein

page_text: described, of an air chamber carried or drawn by the locomotive to
receive and retain atmospheric air under pressure; an air pump operated
by the locomotive, or by steam from the boiler to fill said air chamber;
an independent stationary reservoir to contain a water supply; and
pipes, first, to convey the compressed air to said water reservoir that its
pressure may operate upon the surface of the water therein, and second,
to convey this water under pressure into the tender or tank of the
locomotive; the whole being arranged to operate consecutively and
conjointly, substantially as herein set forth.
In witness whereof, I, the said William Edgar Prall, have here-
unto set my hand and seal, this Twenty-fourth day of October
in the year of our Lord 1872.