IMPROVEMENTS IN SIGNALLING APPARATUS POR RAILWAYS
Year: 1874

page_text: LETTERS PATENT to Austin Chambers, of No. 258, Marylebone
Road, in the County of Middlesex, Signal Engineer, for the Inven-
Scaled the 25th March 1875, and dated the 12th December 1874.
PROVISIONAL SPECIFICATION left by the said Austin Chambers at tho
Office of the Commissioners of Patents, with his Petition, on the
12th December 1874.
I, AUSTIN CHAMBERS, of No. 258, Marylebone Road, in the County
5 of Middlesex, Signal Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN SIGNALLING APPARATUS POR RAILWAYS,"
to be as follows:-
:-
This Invention has for its object improvements in signalling apparatus
for railways, and has reference mainly to improvements upon and further
developements of the Invention forming the subject of Letters Patent
granted to me the 12th day of June, 1874, No. 2045, in which the
semaphore arms or signalling objects or bodies are operated pneumatically
A

page_text: in suchwise that when the pressure of the external atmosphere prevails
in the pipes, tubes, or passages establishing communication between the
signalling station or place and the device which moves the semaphore
arm or other signalling object, the latter is in the position indicative of
danger
signalling station or place and the device which moves the semaphore
arm or other signalling object, the latter is in the position indicative of
danger
My present Invention consists in,-
First. The application and use in conjunction with a collapsible
compressor and a pipe, tube, or passage charged with air or other elastic
fluid for effecting the necessary movements of a semaphore arm or
equivalent apparatus for signalling on railways of a valve operating in
connexion with an orifice in the end of the compressor and carried by
one arm of a lever of the first order having its fulcrum in a standard
attached to the moving end of the compressor, the other arm of the
lever being so arranged in relation to a fixed stop or frame as to come in
contact therewith when the compressor is expanded, thereby raising the
valve and establishing and maintaining the atmospheric pressure within
the compressor until the latter is again compressed.
Secondly. An arrangement of apparatus designed to meet the require-
ments of cases in which the concurrence of two signalmen stationed at
different places is needed to move the signalling object into the position
indicating that a train may pass. In this arrangement the rod of each
semaphore arm or signalling object works at its lower end in a guide and
is formed with a slot, through which is passed a pin forming the fulcrum
of a lever or scale beam having its fulcrum at or near its centre. To
each end of the said lever or scale beam is jointed a rod, the one rod
being attached to the weighted upper end or moving part of a collapsible
vessel or chamber and the other rod to the weighted upper end or moving
part of a second collapsible vessel or chamber. The collapsible vessel or
chamber of one station (say station A) communicates by its pipe with a
compressor of the same station, and the other collapsible vessel or chamber
of the same station communicates by its pipe with a compressor of the
next station (say B). In like manner one collapsible vessel or chamber
of station B communicates with one compressor of that station and its
second collapsible vessel or chamber with a compressor at the next
station in the direction in which trains are to proceed. By this arrange-
ment, supposing the actuating lever at one station to be moved into the
position for compressing the air in its pipe it will cause the expansion of
the collapsible vessel or chamber with which such pipo communicates,

page_text: and through the scale beam will cause a corresponding additional
depression of the moving part of the other collapsible vessel or chamber
of the pair without however moving the semaphore arm until tho
actuating lever of the compressor connected with the second collapsible
vessel or chamber has been moved over so as to compress the air and
expand the second collapsible vessel or chamber connected to the same
scale beam.
Thirdly. An arrangement of collapsible apparatus constructed with
two collapsible chambers for operating a semaphore arm (with or
without lenses) where the concurrence of two persons stationed at
different places is an essential preliminary to the movement of the
semaphore arm into the position indicative of "safety." The pipe from
the compressor of one place or station communicates with the interior
of the lower collapsible chamber, and another pipe which is flexible
establishes a communication between the compressor of the other station
or place and the interior of the upper collapsible chamber. A division
between the two chambers constitutes the top of the lower chamber and
the bottom of the upper chamber. The bottom of the lower chamber is
supported by a bracket attached to the signal post, leaving the other
portions of the two chambers and the division free to move vertically, in
which direction they are guided by a rod passing through a guide. The
necessary movements are communicated to the semaphore arm through
the said rod. When both the collapsible chambers are expanded the
rod is raised and the signal arm is lowered into the "safety" position.
Hence it will be evident that if either of the chambers be collapsed the
rod will be lowered and will so cause the semaphore arm to assume the
horizontal or "danger" position. This arrangement may be modified
by the application of additional chambers to meet the requirements of
cases where the concurrence of more than two persons stationed at
different places is an essential preliminary to the movement of the
semaphore arm into the position indicative of "safety."
2
Fourthly. An arrangement of apparatus designed to meet the require-
ments of cases in which three distinct and separate levers have to .be
moved over in order to move the semaphore arm or signalling body into
the "safoty" or "pass-on" position. This apparatus consists of a
combination of three collapsible vessels, namely, one upper vessel and
two lower vessels, being one collapsible vessel for each of the stations
or places. Each vessel has a pipe establishing communication between
A

page_text: it and one of the stations. The upper collapsible vessel is attached to a
rod, and by its movements operates the semaphore arm and lenses. The
upper vessel is provided with two orifices or pipes and seats for two
india-rubber or other elastic valves, one carried by the upper end of
each of the lower collapsible vessels. Assuming all three vessels or
diaphragms to be expanded the signal will be at "safety," but if any
ono of the three compressor levers be moved back into the " danger'
position so as to reduce the pressure in the corresponding pipe, the upper
vessel will be caused to collapse. This arrangement may be modified by
the application of additional lower chambers or diaphragms.
Fifthly. An arrangement of apparatus which may be substituted for
all but one of the compressors in cases where the concurrence of two or
more operators stationed at different places is an essential preliminary to
the moving of a semaphore arm or signalling body into the "safety" or
"pass-on" position. One arm of a bell-crank lever carries a heavy
valve arranged to close against an elastic seat in a nozzle carried by the
pipe which communicates with the station at which the compressor is
situated, as well as with any other station or stations whose officials may
be required to concur in the movement of the signalling arm. When
the lever is in the "safety" or "pass-on" position, the nozzle is closed
by the valve. Assuming the actuating levers at each of the other
stations in communication with the above mentioned pipe to be in the
same position, the semaphore arm will be in the position indicating
"safety," the air or clastic fluid in the pipe being compressed by the
compressor, which is situated at one of those stations; but if the
actuating lever at any one station be moved over so as to raise the valvo
from its seat the pressure in the pipe will be forthwith reduced to that
of the external atmosphere, thus moving the semaphore arm into the
horizontal or "danger" position.
Sixthly. The combination with a lover or its equivalent for moving
railway points or switches of a pipe, tube, or passage charged with air or
other elastic fluid, and means for increasing or diminishing the pressure
thereof above or below the external atmospheric pressure, such pipe, tube,
or passage having branches or connections to the respective semaphore
arms or other signalling objects or bodies, and being provided with
apparatus operated by the movements of the said lever or its equivalent
for opening and closing communication between the main pipe, tube, or
passage and its respective branches, as well as between the latter and the

page_text: external atmosphere, in such manner as to ensure correct signalling,
according to the position for the time being of the points or switches.
"
Seventhly. An arrangement in which a rod actuated by a collapsible
vessel carries a burner supplied with gas by a flexible tube, or jointed
pipe, or telescope gas pipe. The lantern is divided into two chambers,
one above the other, by an internal division which is formed with a hole
through which the burner passes guided by a frame.
The upper
chaniber is provided with a lens for indicating "safety" or pass-on,"
and the lower chamber with a "danger" lens. When the collapsible
vessel has been expanded the burner is in the upper compartment of the
lamp, so that the light is visible only through the "safety" lens. On
moving over the operating lever so as to collapse the vessel, the burner
will be lowered into the lower compartment, whereupon the light will be
seen only through the danger lens. Where the signalling is to be
effected entirely by means of a light the lamp may be divided into three
compartments by two internal divisons, the collapsible vessel being
arranged within the lower compartment, and carrying tho burner which
is fed by a flexibe tube or otherwise.
Eighthly. An arrangement in which a collapsible compressor actuated
by a spring or weight to compress it is provided with a valve opening
into the outer atmosphere in order by admitting air on the return move-
ment of the hand lever to facilitate the expanding of the vessel.
Ninthly. The application and use as a signalling object or body on
railways of a collapsible vessel so arranged in conjunction with a weight
or spring, and with a pipe, tube, or passage charged with air or elastic.
fluid, and apparatus for changing its pressure as to cause the collapsible
vessel to expand into the "danger" position when the actuating com-
pressor is compressed, or when through a leak in the pipe, tube, or
passage, or from other causes the pressure of the external atmosphere is
established in the pipe, tube, or passage, the compression of the col-
lapsible vessel into the "safety" or pass on” position being effected
by the creation therein of a partial vacuum by the expansion of the
compressor.
66
Tenthly. The combination with a semaphore arm or equivalent object
or body (with or without lenses and a lamp) for signalling on railways
of a pipe, tube, or passage, a collapsible vessel or chamber, an air pump.
or compressor actuated by a lever and a valvo or governing apparatus

page_text: operated by a second lever for establishing communication between the
pipe, tube, or passage leading from the air pump or compressor, and the
pipe, tube, or passage leading to the collapsible vessel, so that after the lever
of the governing apparatus has been changed from the "danger" to the
Isafety "position the necessary compression or exhaustion of air in the
pipe, tube, or passage for changing the signal from the "danger" to the
"safety" position is effected by working the operating lever of the air
pump or its equivalent.
*
Eleventhly. Adapting pneumatic signalling apparatus to work on the
locking system by the use of locking cocks or valves arranged to operate
in conjunction with the cocks or valves, whereby communication is
established and broken as required between the air or gas compressor or
rarefier and the signalling object or body. In applying this a reservoir
of air or gas or vacuum may be employed, or compressors, exhausters, or
pumps to compress or create partial vacuum may be brought into
operation after the cocks or valves have been set in the desired
position.
Twelfthly. The use for signalling on railways of gas burners arranged
in pairs, in conjunction with suitable lenses, divisions, or shades, and
collapsible vessels operated pneumatically for reducing or extinguishing
the light or flame at one burner, and simultaneously increasing or
establishing the light or flame at the other burner, as required, to make
the necessary signals. When the signalling is to be effected by extin-
guishing a light or flame at one burner, and establishing a light or flame.
at the other burner, a curved pipe, tube, or passage is arranged above
the burners with its open ends terminating one over or nearly over each
burner, or a curved plate carried by the division or shade may be substi-
tuted for the curved pipe, tube, or passage. The apparatus may be
arranged with one or more collapsible vessels to each burner.
Thirteenthly. An arrangement of indicating apparatus for shewing
the operator when a signalling object or body worked pneumatically is
in the "danger" position. The top or a moving part of the collapsible
vessel whereby the semaphore arm or other signalling body is actuated is
furnished with a hole covered by a valve so arranged in relation to the
fixed nose or extremity of a pipe that when the signal is in the "danger
position the nose or extremity of the pipe, by opening the valve and
entering the collapsible vessel or valve chamber, allows an amount of
"

page_text: governing the air or fuld passages leading to the signaшing objects or
bodies.
The apparatus herein-before described as being operated by the com-
pression of air or elastic fluid may by suitable modifications be arranged
to be operated by the exhaustion or rarefaction of air or clastic fluid.
The apparatus herein-before described as being operated by the com-
pression of air or elastic fluid may by suitable modifications be arranged
to be operated by the exhaustion or rarefaction of air or clastic fluid.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said Austin Chambers in the Great Seal Patent Office
on the 12th June 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, AUSTIN
CHAMBERS, of No. 258, Marylebone Road, in the County of Middlesex,
Signal Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of December, in the
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Austin Chambers, Her special
license that I, the said Austin Chambers, my executors, administrators,
and assigns, or such others as I, the said Austin Chambers, 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 SIGNALLING
APPARATUS FOR RAILWAYS," upon the condition (amongst others) that I, the
said Austin Chambers, my executors or administrators, by an instrument 1
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.

page_text: First. In the application and use in conjunction with a collapsible
compressor and a pipe, tube, or passage charged with air or other elastic
fluid for effecting the necessary movements of a semaphore arm or
equivalent apparatus for signalling on railways, of a valve operating in
connection with an orifice in the end of the compressor, and carried by
one arm of a lever of the first order, having its fulcrum in a standard
attached to the moving end of the compressor, the other arm of the lever
being so arranged in relation to a fixed stop or frame as to come in
contact therewith when the compressor is expanded, thereby raising tho
valve and establishing and maintaining the atmospheric pressure within
the compressor until the latter is again compressed. Fig. 1 is an
elevation of a signalling apparatus embodying this part of my Invention,
and Fig. 2 is a sectional view to an enlarged scale of part of the com-
pressor end with the valve arrangement. a is the signal post; b, the
semaphore arm, to which is rigidly attached the frame b' carrying the
colored glasses 63, 6'; c is the lamp; d, the rod for operating the signal
arm from the collapsible vessel e; f, the air pipe of the compressor g;
h, the connecting rod; i, ¹, the operating lever; its fulcrum; ³, the
curved locking bar; is an aperture in the compressor end; * is the
lever, which is weighted at one end 7, and at the other end carries the
valve. When the compressor is expanded the end of the lever comes
in contact with the stop or frame 1, thereby raising the valve and
establishing the atmospheric pressure within the compressor until the
lattor is again compressed.

page_text: .
The second part of my Invention consists in an arrangement of
apparatus designed to meet the requirements of cases in which the con-
currence of two signalmen stationed at different places is needed to move
the signalling object into the position indicating that a train may pass.
In this arrangement the rod of each semaphore arm or signalling object
works at its lower end in a guide, and is formed with a slot through
which is passed a pin forming the fulcrum of a lever or scale beam
having its fulcrum at or near its centre. To each end of the said lever
or scale beam is jointed a rod, the one rod being attached to the weighted
upper end or moving part of a collapsible vessel or chamber, and the
other rod to the weighted upper end or moving part of a second
collapsible vessel or chamber. The collapsible vessel or chamber of one
station (say station A) communicates by its pipe with a compressor of
the same station, and the other collapsible vessel or chamber of the same
station communicates by its pipe with a compressor of the next station
(say B). In like manner one collapsible vessel or chamber of station B
communicates with one compressor of that station, and its second
collapsible vessel or chamber with a compressor at the next station in
the direction in which trains are to proceed. By this arrangement,
supposing the actuating lever at one station to be moved into the
position for compressing the air in its pipe, it will cause the expansion
of the collapsible vessel or chamber with which such pipe communicates,
and through the scale beam will cause a corresponding additional
depression of the moving part of the other collapsible vessel or chamber
of the pair, without however moving the semaphore arm until the
actuating lever of the compressor connected with the second collapsible
vessel or chamber has been moved over, so as to compress the air and
expand the second collapsible vessel or chamber connected to the same
scale beam. Fig. 3 is an elevation (with the signal posts turned), and
Fig. 4 is a plan shewing an arrangement of apparatus according to this
part of my Invention. In this arrangement the rod d of each semaphore
arm works at its lower end in a guide d*, and is formed with a slot
through which is passed a lever or scale beam m having its fulcrum
at m¹. To each end of the lever m is jointed a rod d³, d³, the rod d¹
being attached to the weighted upper end of a collapsible vessel e, and
the rod d² to the weighted upper end of a second collapsible vessel e*.
The collapsible vessel e* of station A communicates by its pipe f with
the compressor k of the same station, and the collapsible vessel e of
station A communicates by its pipe f with the compressor k, k, of

page_text: station B. In like manner the collapsible vessel e* of station. B com-
municates with the compressor of that station, and its collapsible
vessel e with a compressor at the next station in the direction of the
arrow. By this arrangement, supposing the lever i at one station to be
moved into the position for compressing the air in its pipe f, it will
cause the expansion of the collapsible vessel with which such pipe com-
municates, and through the scale beam m will cause a corresponding
additional depression of the other collapsible vessel, as shewn at e* and e
(station A), without however moving the semaphore arm b until the
lever of the compressor k, k, connected with the second collapsible
vessel e has been moved over, so as to compress the air and expand the
collapsible vessel e, as shewn at station B.
The third part of my Invention consists in an arrangement of col-
lapsible apparatus constructed with two collapsible chambers for.
operating a semaphore arm (with or without lenses) where the con..
currence of two persons stationed at different places is an essential
préliminary to the movement of the semaphore arm into the position
indicative of “safety.” The pipe from the compressor of one place or
station communicates with the interior of the lower collapsible chamber,.
and another pipe which is flexible establishes a communication between
the compressor of the other station or place and the interior of the
upper collapsible chamber. A division between the two chambers con-
stitutes the top of the lower chamber and the bottom of the upper.
chamber. The bottom of the lower chamber is supported by a bracket
attached to the signal post, leaving the other portions of the two
chambers and the division free to move vertically, in which direction
they are guided by a rod passing through a guide. The necessary move.
ments are communicated to the semaphore arm through the said rod.
When both the collapsible chambers are expanded the rod is raised and
the signal arm is lowered into the "safety" position. Hence it will be.
evident that if either of the chambers be collapsed the rod will be lowered
and will so cause the semaphore arm to assume the horizontal or "danger
position; Figs. 5 and 6 illustrate this arrangement. The pipe f from.
the compressor of one place or station communicates with the interior.
of the lower collapsible vessel e and the flexible pipe f* establishes com-
munication between the compressor of the other station or place, and
the interior of the upper collapsible vessel e*. e is a division which
constitutes the top of the lower vessel e and the bottom of the upper
23

page_text: vessel ex. The bottom of the vessel e is supported by a bracket attached to
the signal post a, as shewn, leaving the other portions of the vessel e, the
division e', and the vessel e* free vertically, in which direction they are
guided by the rod d passing through the guide d'. The necessary move-
ments are communicated to the semaphore arm through the rod d. This
arrangement may be modified by the application of additional chambers
to meet the requirements of cases where the concurrence of more than
two persons stationed at different places is an essential preliminary to the
movement of the semaphore arm into the position indicative of "safety."
"
"
The fourth part of my Invention consist in an arrangement of appa-
ratus designed to meet the requirements of cases in which three distinct
and separate levers have to be moved over in order to move the semaphore
arm or signalling body into the "safety" or "pass on " position. This
apparatus consists of a combination of three collapsible vessels, namely,
one upper vessel and two lower vessels, being one collapsible vessel for each
of the stations or places. Each vessel has a pipe establishing communi-
cation between it and one of the stations. The upper collapsible vessel
is attached to a rod, and by its movement operates the semaphore arm and
lever. The upper vessel is provided with two orifices or pipes and seats for
two india-rubber or other elastic valves carried by the upper end of each
of the lower collapsible vessels. Assuming all three vessels or diaphragms
to be expanded the signal will be at “ safety." But if any one of
the three compressor levers be moved back into the danger
position so as to reduce the pressure in the corresponding pipe, the
upper vessel will be caused to collapse. This arrangement may be
modified by the application of additional lower chambers or dia-
phragms; Figs. 7 and 8 shew this arrangement. e, ex, es, are three
collapsible vessels, that is to say, one collapsible vessel for each of
the stations or places, f being the pipe establishing communication
between one of the stations and the vessel e; f* the pipe establishing
communication between another of the stations or places and the col-
lapsible vessel e*, and f³ the pipe from the third station or place to the
collapsible vessel e³. The large collapsible vessel e is attached to the rod d,
and by its movements operates the semaphore arm and lenses. The
vessel e is provided with two orifices or pipes e³, e¹, the lower rims
of which form seats for two india-rubber or other elastic valves e¹¹, e¹¹,
carried by the upper ends of the collapsible vessels e*, e³. The Drawing
shews the position of the parts as they appear when all three of the

page_text: o llapsible vessels are inflated, or in other words when the air or elastic
fluid has been compressed in each of the three pipes ƒ, f*, ƒ³, by corre-
sponding movements of their respective levers. But if any one of the
three compressor levers be moved back into the "danger" position so as
to reduce the pressure in the corresponding pipe the vessel e will be
caused to collapse. For example, if the lever of the pipe f* be moved
over, the vessel ex by collapsing, as shewn in dotted lines, will draw
down the valve el, so that the air contained in the vessel e will be forced
out through the orifice e³, because the top of the vessel e will be moved
down by the pressure of the rod d. A similar effect will be produced by
the movement of the compressor lever of the pipe f³; or if the com-
pressor lever of the pipef bo moved over, the vessel e will be collapsed
owing to the reduction of pressure in it.
"
The fifth part of my Invention consists in an arrangement of
apparatus which may be substituted for all but one of the compressors
in cases where the concurrence of two or more operators stationed at
different places is an essential preliminary to the moving of a semaphore
arm or signalling body into the "
<<
"safety" or pass out" position. One
arm of a bell-crank lever carries a heavy valve arranged to close against
an elastic scat in a nozzle carried by the pipe which communicates with
the station at which the compressor is situated, as well as with any other
station or stations whose officials may be required to concur in the move-
ment of the signalling arm. When the lever is in the " safety or "pass
on" position the nozzle is closed by the valve. Assuming the actuating
levers at each of the other stations in communication with the above
mentioned pipe to be in the same position the semaphore arm will be
in the position indicating "safety," the air or elastic fluid in the pipo
being compressed by the compressor which is situated at one of those
stations. But if the actuating lever at any one station be moved over
so as to raise the valve from its scat the pressure in the pipe will be
forthwith reduced to that of the external atmosphere, thus moving the
semaphore arm into the horizontal or “danger" position; Figs. 9 and 10
shew this arrangement. The arm of the lever i carries a heavy valve n
arranged to close against an elastic scat f" in a nozzle f¹s carried by the
pipe which communicates with the station at which the compressor is
situated, as well as with any other station or stations whose officials may
be required to concur in the movement of the signalling arm. In the
Drawing the lever i is shown in the," safety" or "pass on " position, the

page_text: nozzle f¹ being closed by. the valve n. Assuming the levers i at each
of the other stations in communication with the pipe f to be in the same
position the semaphore arm will be in the position indicating safety, the
air or elastic fluid in the pipe f being compressed by the compressor
which is situated at one of those stations; but if the lever i at any one
station be moved over in the direction shewn by the arrow (Fig. 9) so as
to raise the valve n from its seat f¼ the pressure in the pipe will be
forthwith reduced to that of the external atmosphere, thus moving the
semaphore arm into the horizontal or "danger" position.
The sixth part of my Invention relates to the combination with a
lever or its equivalent for moving railway points or switches of a pipe,
tube, or passage charged with air or other elastic fluid, and means for
increasing or diminishing the pressure thereof above or below the
external atmospheric pressure, such pipe, tube, or passage, having
branches or connections to the respective semaphore arms or other
signalling objects or bodies, and being provided with apparatus operated
by the movements of the said lever or its equivalent for opening and
closing communication between the main pipe, tube, or passage and
its respective branches, as well as between the latter and the external
atmosphere in such manner as to ensure correct signalling, according
to the position for the time being of the points or switches. Figs. 11
and 12 shew the application of this part of my Invention to the points
or switches at a railway junction; fis the pipe from the compressor or
from a reservoir of compressed air; this pipe terminates in a valvo
box f', in which works a slide valve fi connected by a stud f³, guided
rod f*, and links f³ to the point lever ƒª, which lever is connected by
a stud f' to the points or switches f³, f¹. From the face of the valve
box f¹ there are three ports; one of these ports communicates with a
pipe for actuating the semaphore arm or signal of the line A;
another communicates with a pipe f" for actuating the semaphore arm
or signal of the line B, whilst a third f1 communicates with the
external atmosphere. The Drawing shews the parts in position for a
train to pass along the line A. The pipe f is in communication by the.
port and pipe f" with the signalling arm of line A, which is con-
sequently lowered to the position indicating that a train may procced,
whilst the pipe fis in communication through the valve f2 and port f
with the external atmosphere, so that as the normal or atmospheric pressure
prevails in the pipe f¹ the signal arm of the line B is in the horizontal

page_text: or danger position. It will be evident that on moving the lever fo
over in the direction of the arrow so as to place the points in position for.
a train to proceed from the line A on to the line B, the valve f* will
be moved over, so that the signals will be reversed accordingly. Tho
arrangement shewn is obviously capable of modification without
departing from my Invention.
"
The seventh part of my Invention consists in an arrangement in which
a rod actuated by a collapsible vessel carries a burner supplied with gas
by a flexible tube or jointed pipe or telescope gas pipe. Figs. 13 and 14
shew such an arrangement. d is the rod actuated by the collapsible
vessel e; c¹ is the burner and c is the flexible tube by which it is
supplied with gas. The lantern is divided into two chambers c³, c*, one
above the other, by an internal division c³, which is formed with a hole
through which the burner c¹ passes, guided by the frame c. The upper
chamber is provided with a lens c for indicating "safety" or "pass on
and the lower chamber with a "danger" lens c³. When the collapsible
vessel has been expanded (as shown in Fig. 11) the burner is in the
upper compartment of the lamp so that the light is visible only through
the "safety" lens c'. On moving over the signal operating lever (not
shown in the Drawing) so as to collapse the vessel e the burner will be
lowered into the lower compartment c', whereupon the light will be seen
only through the "danger" lens c. Where the signalling is to be
effected entirely by means of a light the arrangement may be modified
as shewn in Figure 15. In this case the lamp is divided into three com-
partments c³, c², c³, by two internal division's c, c¹, the collapsible
vessel e being arranged within the lower compartment c and carrying
the burner c', which is fed by a flexible tube c³ or otherwise; c' is the
safety" lens and 8 is the " danger" lens. The operation of this
arrangement will be evident.
66
The eighth part of my Invention consists in an arrangement in which
a collapsible compressor actuated by a spring or weight to compress it is
provided with a valve opening to the outer atmosphere in order by
admitting air on the return movement of the hand lever to facilitate the
expanding of the vessel. Fig. 16 is a side elevation, partly in section, of
apparatus constructed according to this part of my Invention. In the.
arrangement shewn the upper part of the compressor g is weighted by
being made of metal, but it will be evident that it may be otherwise
made of sufficient weight, or a separate weight or a spring may be used,

page_text: .
for causing the vessel to collapse. The upper end of the compressor is
provided with a valve o closed by a spring o', as shewn and arranged to
open inward. The apparatus is shewn with the signal arm b in the
inclined or "
pass on " position. On moving the lover i over in the direction
indicated by the arrow the chain p and the weighted upper end of the
compressor will be drawn up. During the earlier portion of such
upward movement the air in the compressor will be rarefied, so that the
valve o will be opened by the excess of pressure of the external atmo-
sphere, thus admitting air into the compressor, whereby its expansion
will be expedited. Assuming the lever i to be in the position indicated
by the dotted line, the valve stem being against the stop q, and the valve
consequently open, on now moving it (the lever) into the position in
which it is shewn in full in the Drawing the chain p will be slackened,
and the weighted upper end of the compressor being released will by its
gravity descend and compress the air for changing the signal without its
being necessary for the operator to retain his hold of the lever i during
such descent. It will be evident that a similar valve arrangement may
be applied to the lower end of the compressor in apparatus constructed
according to Fig. 5 of the Drawings accompanying the Specification of
my former Patent, No. 2045, dated 12 June, 1874.
"
Another part of my Invention relates to the combination with the
semaphore arm or equivalent object or body (with or without lenses
and a lamp) for signalling on railways of a pipe, tube, or passage,
a collapsible vessel or chamber, an air pump, compressor, or rarefier
actuated by a lever, and a valve or governing apparatus operated by a
second lever, for establishing communication between the pipe, tube, or
passage leading from the air pump, compressor, or rarefier and the pipe,
tube, or passage. leading from the air pump, compresser, or rarefier, and
the pipe, tube, or passage leading to the collapsible vessel, so that after the
lever of the governing apparatus has been changed from the "danger
to the "safety" position the necessary compression or exhaustion of air
in the pipe, tube, or passage for changing the signal from the "danger"
to the "safety" position is effected by working the operating lever of
the air pump or its equivalent. Fig. 17 illustrates this part of my
Invention as applied when the signalling object is arranged to be moved
into the "safety" or "pass on" position by reducing the pressure in the
pipe below that of the external atmosphere. f' is a point lever provided
with a stopping or locking cam r; f20 is a pipe communicating with a
rareficr g actuated by a lever i. Another pipe (S) communicates with a

page_text: collapsible vessel or chamber, which may be like that shewn at e in
Fig. 16, but connected to the semaphore 6 at the opposite side of its
fulcrum ; f is a three-way cock operated by a lever 8 for establishing
communication between the pipe f leading from the rarefier 9 and the
pipe f.
I
According to the Drawing the parts are in the relative positions which
obtain when the signalling object is in the "danger" position, and it
will be seen that the lever s cannot be lowered for altering the signal
until the points have been altered by moving over the lever ƒ in the
direction indicated by the arrow. On so moving over that lever however
the position of the points will be altered, and the notch r' in the stopping
or locking cam by coming under the pin s' of the levers will enable
that lever to be lowered so as to establish communication between the
pipe and the collapsible vessel of the signalling object through the
pipe f, whereupon the necessary exhaustion of air in the pipes f, f, and
collapsible vessel for changing the signal from the "danger" to the
safety" position may be effected by working the operating lever i of
the rarefier.
"
Fig. 18 represents a modification in which the levers is made self-
acting by means of a weight. The operation of this arrangement will be
readily understood from the Drawing without further description. The
arrangement of the lovers f* and s with the stopping or locking cams r
resembles the well known arrangement described in the Specification of
former Letters Patent granted to me the 5th day of January 1860
(No. 31).
Another part of my Invention consists in an arrangement of indicating
apparatus for shewing the operator when a signalling object or body
worked pneumatically is in the danger position. A moving part of the
collapsible vessel whereby the semaphore arm or other signalling body is
actuated is furnished with a hole covered by a valve so arranged in
relation to the fixed nose or extremity of a pipe that when a signal is in
the danger position the nose or extremity of the pipe by opening the
valve and entering the collapsible vessel or valve chamber allows an
amount of air or elastic fluid to pass through the pipe which actuates
the indicator in the operator's signal box, and thereby shews him that
the signal is in the "danger" position. Fig. 19 illustrates this part of
my Invention.
e is the upper end of a collapsible vessel for actuating
a semaphore arm or other signalling body; e" is a hole in the said end
B

page_text: covered by a valvet pressed towards the movable end of the vessel by a
spring is the fixed nose or. extremity of a pipe leading to a water
gauge or other suitable indicator in the signal box; u¹ is a vulcanized
india-rubber valve or packing piece carried by the nose or extremity of
the pipe. I provide for cases where signalling levers are arranged in
sets or series of two or more levers (rendering it inconvenient to provide
a separate air pump, compressor, or rarefier for each semaphore arm or
set of signalling bodies) by so combining an air pump, compressor, or
rarefier with a set of levers connected with apparatus for governing the
opening and closing of communication between such air pump, com-
pressor, or rarefier and the respective semaphore arms or other signalling
bodies or objects, that when any one of the signalling objects or bodies
is required to be moved the requisite lever of the series may be moved
into the proper position, and the signalling object or body subsequently
operated by moving over the lever or equivalent portion of the pump,
compressor, or rarefier. Figs. 20, 21, and 22 illustrate this improve-
ment. are point levers provided with stopping or locking plates r in
the manner described in the Specification of my aforesaid Patent of 1860.
f20 is a main pipe communicating with an air pump, compressor, or
rarefier; are the pipes communicating with the respective collapsible
vessels or chambers, by the opening and closing of which the semaphore
arms or signalling bodies are to be actuated; f" are the three-way cocks,
each operated by a levers for establishing communication between the
pipe and the corresponding pipe f. The mode of operating this
arrangement is the same as in cases where the same system of locking
apparatus is used in conjunction with wires or rods for communicating
the necessary movement to the semaphore arms or signalling bodies
according to my Patent of 1860, the levers & and pneumatic apparatus
being substituted in my present arrangement for the stirrups, chains,
and pulleys used in the old arrangement.
My Invention has reference, lastly, to a method of working pneu-
matically a point lock for securing a pair of points at a distance. This
is accomplished by means of a collapsible vessel arranged in conjunction
with a disc or plate having a notch or hole in it, the said disc or plate
being so governed by the collapsible vessel as to allow the switch rod to
be shifted or locked, as desired. Figs. 23 and 24 illustrate this improve-
ment. e is the collapsible vessel which is provided with a couple of
small standards having a cross piece which carries a depending bolt w

page_text: arranged to operate in connexion with a notch or hole in the stopping or
locking disc or plate r. Fig. 23 shews the disc or plate "locked" in
position by the bolt w so that the "point" lever f* cannot be moved
over until the proper lever (not shewn in the Drawing) is moved,
whereby the pressure in the vessel e is controlled from a distance by the
person whose concurrence is needed for the purpose.
It will be evident that the apparatus herein-before described as being
operated by the compression of air or elastic fluid may by suitable modifi-
cations be arranged to be operated by the exhaustion or rarefaction of
air or elastic fluid, and vice versa.
It will also be evident that in some cases a collapsible vessel may be
used as the signalling object in lieu of a semaphore arm, such collapsible
vessel being provided with a spring or weight for expanding it as
required and being collapsed by reducing the pressure of elastic fluid in
a pipe, tube, or passage below the pressure of the external atmosphere, as
herein-before described.
In my Provisional Specification I contemplated the use of-locking
cocks or valves arranged to operate in conjunction with the cocks or.
valves, whereby communication is established and broken, as required,
between the air or gas compresser or rarefier and the signalling object or
body; also the use of gas burners arranged in pairs in conjunction with
suitable lenses, divisions, or shades, and collapsible vessels operated
pneumatically for reducing or extinguishing the light or flame at one
burner, and simultaneously increasing or establishing the light or flame
at the other burner and the operating signalling objects at points by so
arranging pneumatic apparatus in connexion with the points or switches
as by the moving over of the points to compress air or elastic fluid in a
pipe, tube, or passage provided with a collapsible or expanding and
contracting vessel or chamber operating the valve cock or device
governing the air or fluid passages leading to the signalling objects or
bodies, but as I now entertain some doubt whether these several arrange-
ments would possess all the advantages I anticipated from their use I do
not lay any claim to them.
Having described the nature of my said Invention, and explained the
manner of carrying it into practical effect, I hereby declare that I do
not lay claim to the separate use of any of the individual pieces
composing the apparatus constructed according to my Invention, as

page_text: herein-before described, but what I consider to be novel and original
and therefore claim as the Invention secured to me by the herein-before
in part recited Letters Patent is,-
First. In a railway signalling apparatus the application and use in
conjunction with a collapsible compressor and a pipe, tube, or passage
charged with elastic fluid for operating by change of pressure a
semaphore arm or its equivalent, of a valve operating in connexion with
an orifice in the end of the compressor, and so arranged in relation to a
stop or stud that when and so long as the compressor is in its expanded
condition the valve shall be open, thereby establishing and maintaining
the atmospheric pressure within the compressor until the latter is again
moved or compressed, substantially as described with reference to
Figs. 1 and 2 of the Drawings.
Secondly. The arrangement of apparatus for signalling on railways,
substantially as shewn in and described with reference to Figs. 3 and 4
of the Drawings, for the purpose specified.
Thirdly. The apparatus shewn in and described with reference to
Figs. 5 and 6 of the Drawings when applied in conjunction with a pipe,
tube, or passage charged with air or clastic fluid, and apparatus for
changing the pressure of such air or elastic fluid for operating a
semaphore arm or its equivalent where the concurrence of two persons
stationed at different places is an essential preliminary to the movement
of the signalling object into the position indicative of "safety."
Fourthly. The construction and application of apparatus, substantially
as shewn in and described with reference to Figs. 7 and 8 of the
Drawings, for the purpose specified.
Fifthly. The apparatus shewn in and described with reference to
Figs. 9 and 10 of the Drawings when applied in conjunction with a pipe,
tube, or passage charged with air or elastic fluid, and apparatus for
changing the pressure of such air or elastic fluid for operating a
semaphore arm or its equivalent where the concurrence of two or moro
persons stationed at different places is an essential preliminary to the
movement of the signalling object into the position indicative of
safety."

page_text: or other elastic nuid, and means for increasing or diminishing the
pressure thereof above or below the external atmospheric pressure, such
pipe, tube, or passage having branches or connexions to the respective
semaphore arms or other signalling objects or bodies, and being provided
with apparatus operated by the movements of the said lever or its
equivalent for opening and closing communication between the main
pipe, tube, or passage, and its respective branches as well as between
the latter and the external atmosphere, in such manner as to ensure
correct signalling, according to the position for the time being of the
points or switches.
Seventhly. The combination of the parts shewn in and described with
reference to Figs. 11 and 12, for the purposes specified.
Eighthly. The combination of parts constituting the improved railway
signalling apparatus shown in and described with reference to Figs. 13
and 14 of the Drawings.
Ninthly. The apparatus shewn in and described with reference to
Fig. 15 of the Drawings, for the purpose specified.
Tenthly. In railway signalling apparatus wherein the semaphore arm
or its equivalent is operated by changing the pressure of clastic fluid in
a pipe, tube, or passage by means of a collapsible compressor; the appli-
cation and use in connection with an aperture in such compressor of a
valve o, substantially in the manner described, with reference to Fig. 16,
for the purpose specified.
Eleventhly. The combination with a semaphore arm or its equivalent
for signalling on railways, of a pipe, tube, or passage charged with
elastic fluid, a collapsible vessel or chamber operating by its movement
the semaphore arm or equivalent, an air pump, compressor or rarefier
actuated by a lever, and a valve or governing apparatus operated by a
second lever, said valve or governing apparatus being interposed between
the pipe, tube, or passage leading from the air pump, compressor, or
rarefier, and the pipe, tube, or passage leading to the collapsible vessel
or chamber so as to prevent the giving of a "safety" signal until the
lever of the valve or governing apparatus has been moved from the
"danger" position.
Twelfthly. In pneumatic signalling apparatus for railways, the appli-
cation and use for indicating to the operator the position of the signalling

page_text: object or body, of a valve arranged in connexion with a hole in a moving
part of the collapsible vessel, whereby the signalling body is actuated,
said hole and valve being so arranged in relation to a pipe communi-
cating with an indicator placed near the operator as at the time
proper
to establish communication between the said indicator and the interior
of the collapsible vessel, and thereby to indicate that the signal has
resumed the danger position, substantially as described.
Thirteenthly. In railway signalling apparatus wherein the semaphores
or their equivalents are operated by changing the pressure of elastic fluid
in pipes, tubes, or passages, combining an air pump, compressor, or
rarefier with a series of semaphore arms or equivalent signalling objects
by the interposition of a main pipe and a corresponding series of
branches, each furnished with a valve or governing apparatus operated
by a suitable lever, substantially as described for the purpose specified.
Lastly. The method herein-before described with reference to Figs. 23
and 24, of working a point lock pneumatically for securing a pair of
points at a distance.
In witness whereof, I, the said Austin Chambers, have hereunto
set my hand and seal, this Twelfth day of June, in the year
of our Lord One thousand eight hundred and seventy-five.