IMPROVEMENTS IN APPARATUS FOR SIGNALLING ON RAILWAY TRAINS, AND FOR OTHER LIKE PURPOSES
Year: 1866

page_text: LETTERS PATENT to Alfred Henry Hart, of Gresham Street, in the
City of London, Manufacturer, for the Invention of "IMPROVEMENTS IN
APPARATUS FOR SIGNALLING ON RAILWAY TRAINS, AND FOR OTHER LIKE
PURPOSES."
Scaled the 5th March 1867, and dated the 7th September 1866.
PROVISIONAL SPECIFICATION left by the said Alfred Henry Hait
at the Office of the Commissioners of Patents, with his Petition, on
the 7th September 1866.
I, ALFRED HENRY HART, of Gresham Street, in the City of London,
Manufacturer, do hereby declaro the nature of the said Invention for "Iч-
PROVEMENTS IN APPARATUS FOR SIGNALLING ON RAILWAY TRAINS, AND FOR OTHER
LIKE PURPOSES," to be as follows:-
My Invention consists of the arrangement or combination of the parts
of a signalling apparatus berein-after described, whereby the passengers in
a railway train can communicate with the driver and guard of the train.
My Invention may also be employed for signalling generally. A strong
metallic tube is extended along the top or other convenient part of each of the
carriages of the train, the ends of the tube of one carriage being connected

page_text: by flexible air-tight junctions with the ends of the tubes of the carriages in
front and back of it. There is thus formed an air-tight tubo extending from
end to end of the train. The said tube terminates at one end on the tender
of the engine, and at the other end on the guard's van. The ends of the
tube are open and are ground flat. Near each end of the tube is a lever
turning in a vertical plane and carrying at the end of one of its arms a flat
closing plate which fits air-tight against the flat end of the tube. An exhausting
pump is connected with the tube and by working the said pump after the
said closing plates have been brought against the ends of the tube the
diminished pressure within the said tube causes the said closing plates to be
fixed against the ends of the tube by the pressure of the atmosphere. The
levers carrying the closing plates are provided with hammers or strikers,
which when the levers fall by the liberation of the closing plates from the
ends of the tube, as herein-after explained, strike bells and call the attention
of the guard or driver.
The liberation of the closing plates and the consequent signalling is
effected by the passengers in the train in the following manner:-At the
required positions on the tube lateral openings are made, each of the said
openings being provided with an air-tight plate capable of covering or
uncovering the opening by a sliding motion in a vertical plane. By pulling
a handle or cord the sliding plate may be raised or moved from off the
opening by a passenger in the train.
The action of the apparatus is as follows:-In order to prepare the apparatus
for signalling the closing plates are brought against the ends of the tube and
the exhausting pump is worked. A partial vacuum is formed in the tube, and
the end plates are thereby fixed against the ends of the tube. In order to
signal the guard and driver it is only necessary to pull the handle or cord
connected with one of the sliding plates covering the lateral openings; by
this means air is allowed to enter the tube and tho pressure of the air within
the tube becoming equal to that of the air without the closing plates are no
longer held against the ends of the tube by the pressure of the atmosphere;
the levers carrying the said closing plates fall, their bam mers or strikers
striking the bells and calling the attention of the guard and driver. The
sliding plates covering the lateral openings close by their own weight or by the
action of a spring; the said plates, however, close gradually and not until
the pressure of the air within the tube equals or nearly equals that of the air
without; this gradual closing is caused by the pressure of the plate against
the sides of the opening by the atmosphere causing sufficient friction to

page_text: prevent the falling of the plate until an equilibrium is established or nearly
established between the air within and without the tube. Instead of making
the falling levers act upon bells they may operate upon any other apparatus
which will attract the attention of the guard and driver.
Although I have only described my Invention as applied to signalling on a
railway train, yet my said Invention may be employed for signalling generally.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alfred Henry Hart in the Great Seal Patent Office on
the 6th March 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, 'ALFRED
HENRY HART, of Gresham Street, in the City of London, Manufacturer, send
greeting.
WHEREAS IIer most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of September, in the year of our
Lord One thousand eight hundred and sixty-six, in the thirtieth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alfred Henry Hart, Her special licence that I, the said
Alfred Henry Hart, my executors, administrators, and assigns, or such
others as I, the said Alfred Henry Hart, my executors, administrators,
and assigns, should at any time agree with, and no others, from time
to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN APPARATUS FOR
SIGNALLING ON RAILWAY TRAINS, AND FOR OTHER LIKE PURPOSES," upon the
condition (amongst others) that I, the said Alfred Henry Hart, my
executors or administrators, by an instrument in writing under my, or their,
or one of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Alfred Henry Hart, do hereby
declare the nature of the said Invention, and in what manner the same is

page_text: to be performed, to be particularly described and ascertained in and by tho
following statement thereof, that is to say-
My Invention consists of the arrangement or combination of the parts of a
signalling apparatus herein-after described, whereby the passengers in a railway
train can communicate simultaneously with the driver and guard of the train.
My Invention may also be employed for signalling generally. A strong
metallic tube is extended along the top or other convenient part of each of
the carriages of the train, the ends of the tube of one carriage being connected
by flexible air-tight junctions with the ends of the tubes of the carriages in
front and back of it; there is thus formed an air-tight tube extending from end
to end of the train. The said tube terminates at one end on the tender of the
engine and at the other end on the guard's van. The ends of the tube are
open. Near each end of the tube is a lever or spring arm turning in a vertical
plane and carrying a closing plate or plug which fits air-tight against or inside
the end of the tube. An exhausting pump is connected with the tube, and
by working the said pump after the said closing plates or plugs have been
brought against or introduced into the open ends of the tube the diminished
pressure within the said tube causes the said closing plates or plugs to be
fixed against the ends of the tube by the pressure of the atmosphere. The
levers or spring arms carrying the closing plates or plugs are provided with
hammers or strikers which when the levers fall, or the spring arms are at
liberty to move by the liberation of the closing plates or plugs from the ends
of the tube as hercin-after explained, strike bells and call the attention of the
guard or driver. The liberation of the closing plates and the consequent sig-
nalling is effected by the passengers in the train in the following manner :-
At the required positions on the tube lateral openings are made, each of the
said openings being provided with an air-tight plate capable of covering or
uncovering the opening by a sliding motion in a vertical plane.
handle or cord the sliding plate may be raised or moved from off
by a passenger in the train.
By pulling a
the opening
In
The action of the apparatus is as follows:-In order to prepare the
apparatus for signalling the closing plates are brought against the ends of the
tube and the exhausting pump is worked; a partial vacuum is formed in the
tube, and the end plates are thereby fixed against the ends of the tube.
order to signal the guard and driver it is only necessary to pull the handle or
cord connected with one of the sliding plates covering the lateral openings;
by this means air is allowed to enter the tube, and the pressure of the air
within the tube becoming equal to that of the air without the closing plates

page_text: are no longer held against the ends of the tube by the pressure of the atmos-
phere; the levers carrying the said closing plates fall, their hammers or
strikers striking the bells and calling the simultaneous attention of the guard
and driver; the sliding plates covering the lateral openings close by their own
weight or by the action of a spring. The said plates however close gradually
and not until the pressure of the air within the tube equals or nearly equals
that of the air without; this gradual closing is caused by the pressure of the
plate against the sides of the opening by the atmosphere causing sufficient
friction to prevent the falling of the plate until an equilibrium is established
or nearly established between the air within and without the tube. Instead
of making the falling levers or spring arms act upon bells they may act upon
any other apparatus which will attract the attention of the guard and driver.
Although I have only described my Invention as applied to signalling on a
railway train yet my said Invention may be employed for signalling generally.
Having explained the nature of my Invention I will proceed, to describe
with reference to the accompanying Drawing, the manner in which the samo
is to be performed when applied to signalling on railway trains.
Figures 1 and 2 represent partly in elevation, and partly in section, the end
of the metallic tube situated in the guard's van, and also the apparatus used
for closing the end of the tube and giving the signal. In Figure 1 the end
of the tube is represented closed, and in Figure 2 open.
On the tender of the
engine the opposite end of the metallic tube is placed, and similar apparatus
a is
to that represented in Figures 1 and 2 is used in connection therewith.
the metallic tube, which is extended along the top or side or other convenient
part of each of the carriages of the train. In the end of the tube a terminating
in the guard's van, and that terminating in the tender of the engine is an
elbow 6, the end or opening in which can be closed at pleasure by a block or
closing plate c carried by the spring arm d; the open end of the elbow band the
closing plate or plug c, are covered with india-rubber or other elastic material
so as to make an air-tight joint. The end of the spring arm d also carries a
hammer or projecting piece e which on the rebound of the spring arm dis
made to strike the bell f as herein-after explained. Instead of the spring
arm da lever may be used. Figure 3 represents the exhausting pump and
parts connected with the same for exhausting the air from the tube a running
from end to end of the train. I prefer to place the said pump in the guard's brake
van; 9 is the pump provided with piston, piston rod, stuffing box, and the
usual parts of exhausting pumps. The said pump is worked by the cranked
shaft h to which the piston rod is connected in the manner represented. On

page_text: the end of the cranked shaft h is a fly wheel i, the shaft h is turned by the
winch or handle k, the said shaft h turns in bearings 1, 1, the said bearings
being carried by the metal plate n fixed by screw bolts to the partition p of
the guard's van. The fly wheel is covered by the casing q, the bottom of
the pump cylinder is made spherical, the said spherical bottom fitting in a
cup carried by the bearing s. The said cup is covered by a cap t having
a slot in it through which the pump cylinder moves when the pump is
worked by the handle k. The bottom of the cup r is connected by the pipe u
with the tube a running from end to end of the train, and the pipe u
communicates with the pump cylinder 9 by a passage in its spherical
bottom. On turning the crank shaft h by the handle k an oscillatory motion
is given to the pump, the said pump moving in the slot in the hemispherical
cap r, and air is exhausted from the tube a through the pipe u by the said
pump.
Figure 4 represents partly in section and partly in elevation, and Figure 5
in plan, the arrangement of the flexible junctions which I use between every
two carriages of the train. a, a, is the metal tube, supported by preference
by the buffer boards 9, 9, of the carriage. The ends of the metal tube a
project through the said buffer boards 9, 9, and are screwed, and on the
screwed ends inetal collars or mounts h, h, are screwed; to these mounts or
collars h, h, the ends of the flexible tube i, supported internally by coiled wire
are connected by metal nozzles ; these nozzles are slightly taper and slip
into the collars h, h, and may be held securely in their places by springs,
screws, or otherwise. The flexible tube i may be protected externally by a
coating of leather. The collars h, h, in addition to providing for the connection
of the flexible tube to the fixed metal tube also serve for tightening the said
fixed tube to the buffer boards at the ends of the carriage. By means of tho
flexible connections i the lengthening or shortening of the distance between
the carriages is provided for.
Figure 6 represents in front elevation, and Figure 7 in cross section that
part of the fixed tube by which a passenger in the train may signal to the
driver or guard of the train. a, a, is the fixed metal tube at the required
positions, on which metal collars are fixed concentrically by screws m. The
flat side of the collar has a lateral inlet or opening n made in it, which
passes through the said collar, and also through the fixed tube a (sec
Figure 7); this inlet or passage n is covered by a plate p working air-tight
against the said inlet. The plate p turns on the centre 7, and is pressed down
by the spring r. By means of the plate p the inlet or passagen can bo

page_text: covered or uncovered at pleasure. A chain or cord s connected to the free
end of the lever or closing plate p passes to each of the compartments of the
railway carriage. By pulling a handle or cord in the compartment of the
carriage connected with the cord, or chain, or wire s, the plate p is raised by
a sliding motion, and the inlet or opening n thereby uncovered. On loosing
the handle or cord described the plate p is pressed down by the spring r, and
made to close the inlet or opening n. The lifting of the plate p is limited by
the stop t, and its downward motion by the stop u.
In order to prepare the apparatus for signalling the closing plates or plugs c
(Figures 1 and 2) are brought against and made to close the ends of the
elbows 6 of the tube a situated in the guard's van and engine tender (seo
Figure 1), and the exhausting pump (Figure 3.) is worked so as to form a
partial vacuum in the tube a, and thereby fix by atmospheric pressure the
plates or plugs c in the ends of the elbows b. When it is required to signal
the guard or driver one of the sliding plates p is raised by the passenger in
the manner herein-before explained so as to uncover the inlet n to the tube a.
By this means air is allowed to enter the tube a, and the pressure of the air
within the tube becoming equal to that of the air without the closing plates
or plugs c at the ends of the tube are no longer held in the elbows b. The
spring arms d being unsupported fall, and the hammers e by the action of the
said spring arms strike the bells f, as indicated in dotted lines in Figure 1,
and simultaneously call the attention of the guard and driver. The cord. or
wire passing from the lateral inlet to the compartment may be connected with
a tell-tale indicator fitted at carriage sido to acquaint the guard from whence
the summons proceeds. On removing the hand from the handle or cord
connected to the cord or chains the lateral inlet of the fixed tube a is
gradually closed, and by closing the ends of the tube and exhausting the air
therefrom the apparatus is again ready for use. In the event of any casualty
to the train the tearing asunder of the junctions between the carriages will
be summons to driver and guard equal to signal from passenger. Instead of
making the spring arms or levers act upon bells they may be made to act
upon any other apparatus which will attract the attention of the guard and
driver. The apparatus described and represented may be used for signalling
generally.
Having now described the nature of my Invention, and the manner in
which the same is to be performed, I wish it to be understood that I do not
limit myself to the precise details herein-before described and illustrated in
the accompanying Drawing, as the same may be varied without departing

page_text: from the nature of my Invention; but I claim as my Invention, arranging
or combining, substantially in the manner herein-before described and
illustrated in the accompanying Drawing, the parts of apparatus for signalling
on railway trains and for other like purposes.
In witness whereof, I, the said Alfred Henry Hart, havo hereunto set
my hand and seal, this Fourth day of March, in the year of our Lord
One thousand eight hundred and sixty-seven.
Witness,
RICHARD SKERRETT,
Clerk to George Shaw,
Birmingham.
ALFRED HENRY HART. (L.S.)