IMPROVEMENTS IN RAILWAY, SHIP, - AND OTHER SIGNALS
Year: 1861

page_text: LETTERS PATENT to Charles Pemberton, of Deptford, in the County of
Kent, Engineer, for the Invention of "IMPROVEMENTS IN RAILWAY, SHIP,
- AND OTHER SIGNALS."
Sealed the 21st February 1862, and dated the 31st August 1861.
PROVISIONAL SPECIFICATION left by the said Charles Pemberton at the
Office of the Commissioners of Patents, with his Petition, on the 31st
August 1861.
I, CHARLES PEMBERTON, of Deptford, in the County of Kent, Engineer,
"do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
RAILWAY, SHIP, AND OTHER SIGNALS," to be as follows:-
I effect the working of the moveable arm of the ordinary railway distance
signal in the following manner:-To the signal post a fixed piston is attached,
and on the said piston a hollow cylinder works. The said cylinder is connected
by means of a connecting rod with the moveable arm of the signal, and the
raising of the said cylinder produces the depression of the said arm, and the
depression of the said cylinder produces the elevation ofthe said arm. The rising
motion of the cylinder upon the piston is produced by the forcing of air into
the said cylinder, and the falling motion of the said cylinder is produced by
the exhaustion of the said cylinder. The condensation and rarefaction of the
D

page_text: air in the cylinder is thus effected. Atany required distance from the signal
is a condensing and exhausting apparatus. The said apparatas consists of a
short hollow cylinder, in the axis of which is a screw, capable of a rotatory
motion by means of a winch. The threads of the said screw work air tight
or nearly so against the inside of the cylinder. The said cylinder is situated
horizontally, and contains mercury. By turning the axis of the screw the air
is forced in one or other direction through the cylinder, the passage of the air
between the threads of the screw being prevented by the mercury in which the
lower part of the screw is immersed. A three-way.cock is fixed at the closed
end of the cylinder, by properly turning which cock the apparatus may be put
in communication by means of a pipe with a distance signal on either side of
the railway station, and by turning the winch of the apparatus, the policeman
or attendant can either exhaust or condense the air in the moveable cylinder
of the distance signal, and thereby give the required signal. I make the signal
post of a square tube of iron, one side of which is made into a ladder, and I
raise and lower the signal lamp inside the tube by means of a chain passing
over pulleys.
The condensing and exhausting apparatus may be employed to actuate
other than railway signals. I apply the said apparatus for signalling from the
engine room to the deck of steam ships in the following manner:-On the
deck is a dial plate, at the back of which is a chamber, nearly divided into
two compartments by a diaphragm. One compartment of the chamber com
municates by a pipe with the condensing and exhausting apparatus, and the
other compartment communicates with the atmosphere. The air in passing
from one compartment to the other passes over a concave curved plate or seat,
and through a slit formed by the said plate and the edge of a hanging flap or
plate suspended over it. The curve of the plate is of larger radius than the
Hap, and the centre of the said curve is higher than that of the flap, so that
when the flap moves in either direction, the space between it and the curved
plate is greater than when the said plate hangs in its normal position. To the
axis of the flap an index finger is fixed, and as the condensing and exhausting
apparatus is worked, the hanging flap is forced or drawn in one or other
direction; and indicates by the distance to which it moves the index finger the
speed of the engines, and by its direction the direction of the engine's motion.
Either of the signals described may be applied to other purposes than those
with reference to which I have described them.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Pemberton in the Great Seal Patent Office on the
25th February 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
PEMBERTON, of Deptford, in the County of Kent, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of August, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Charles Pemberton, Her special licence that I, the said Charles Pember-
ton, my executors, administrators, and assigns, or such others as I, the said
Charles Pemberton, 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
RAILWAY, SHIP, AND OTHER SIGNALS," upon the coudition (amongst others) that
I, the said Charles Pemberton, my executors or administrators, by an instru-
ment 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Charles Pemberton, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the fol-
lowing statement thereof, that is to say :—
My Invention consists, firstly, of the improvements herein-after explained
and illustrated in Figures 1 and 2 of the accompanying Drawing, in con-
structing and working such signals as consist essentially of a moveable arm
capable of being raised and lowered, such as the ordinary railway distance
signal.
Figure 1 represents in front elevation, and Figure 2 in side elevation, a
railway distance signal constructed according to my Invention. To the signal
post a, a fixed piston 6 is attached by means of a piston rod c, which is hollow,
and with which said hollow piston rod c a piped communicates. The piston
rode is supported on the bracket c². On the said piston b a hollow cylinder e

page_text: works, the said cylinder e being open at botton and closed at top. The said
cylinder e is connected by means of a connecting rod and arm g with the
axis h, carrying the moveable arm i of the signal. The said cylinder e acts as
a.counterbalance weight to the arm. When the cylinder e is raised upon
the piston b the urin iis depressed, and when the cylinder e is depressed upon
the piston 6 the armis raised. The last described positions of the cylinder
and arm are those represented in the Drawing. The depressed position of the
armi is indicated by dotted lines in Figure 1. The rising motion of the
cylinder e upon the piston bis produced by forcing air through the pipe d'and
hollow piston rod c into the space between the top of the piston and top of
the cylinder; and the reverse or falling motion of the said cylinder upon the
piston is produced by exhausting the air in the space between the top of
the piston and top of the cylinder, which compression and exhaustion of air is
effected through the pipe d and hollow piston rod c. The condensing and
exhausting apparatus which I prefer to employ to actuate the signal, Figures 1
and 2, is herein-after described and illustrated in the accompanying Drawing,
but any other condensing and exhausting apparatus may be employed.
Instead of a fixed piston with a cylinder moving on it, a flexible cylinder,
capable of expanding and contracting in the direction of its length, similar to
the bellows of a concertina or accordion, may be einployed, the bottom of the
said flexible cylinder being attached to the bracket c2, and the top of the said
cylinder being connected with the connecting rod. By condensing air in or
exhausting air from the said flexible cylinder it may be made to lengthen or
shorten, and to depress or raise the arm i. When a flexible cylinder is used,
the arm i must be counterbalanced. Or an elastic or flexible expanding
vessel of any other figure may be employed in place of a flexible cylinder; but
I prefer the arrangement represented in Figures 1 and 2.
My Invention consists further in making the sigual post a, Figures 1 and 2,
of a square tube of iron, one side of which is made into a ladder, the rounds
or steps of which are marked in Figure 1. I raise and lower the signal
lamp to the bull's eyes or leuses a³ in the tube a, by means of a continuous
cord or chain m, passing over the pulleys n, o. The cord or chain m is
fastened at one end to the top of the lamp, and passing over the pulleys n, o,
is fastened at the other end to the bottom of the lamp. The raising and
lowering of the lamp is effected by a winch applied to the axis of the
lower pulley o. The post a is connected by a joint p at its bottom with the
cross bars or foot 9 (shewn in plan in Figure 2 A), so that the said post or
tube à may be placed horizontally until the suid cross pieces or foot q is made

page_text: fast to the ground, when the said post or tube a may be raised into a vertical
position, and fixed by screws and screw nuts as represented at r.
My Invention consists further in the instrument or apparatus herein-after
described and represented in front elevation in Figure 3, and in longitudinal
section in Figure 4 of the Drawing, which I prefer to use for condensing and
exhausting the air by which the signal, Figures 1 and 2, is worked. The said
apparatus consists of a short hollow metallic cylinder s, in the axis of which
is a screw t capable of receiving a rotatory motion, by means of a winch applied
to its axis u. The threads of the screw t work air-tight, or nearly air-tight,
against the inside of the cylinders, excepting below the dotted line w. The
said cylinder s is situated horizontally, and contains mercury to about the level
of the dotted line w³, Figure 4. At the end s² of the cylinder 8 is a hole a,,
effecting a communication between the air and the interior of the said end s²
of the cylinder, and in a hole at the end s of the cylinder, and by preference
on the highest point of the said cylinder is a three-way cock y. By turning
the axis u of the screw, air is forced in one or other direction through the
cylinder, the passage of the air between the threads of the screw being pre-
vented by the mercury in which the lower part of the screw is immersed.
The apparatus, Figures 3 and 4; is placed at any required distance from the
signal Figures 1 and 2, the pipe of the said signal being connected with
one of the exit pipes of the three-way cock y.
Another signal, similar to the signal, Figures 1 and 2, ou the other side of
the railway station, or elsewhere, may be connected with the other exit pipe.
of the three-way cock y. By putting the handle y² in the proper position, and
turning the axis win one or other direction, the policeman or attendant at the
apparatus, Figures 3 and 4, can exhaust or condense at pleasure the air in the
moveable cylinders of either of the distance signals, and at the same time
work the points where required. The condensing and exhausting apparatus,
Figures 3 and 4, may be employed to actuate other than railway signals.
My Invention consists, lastly, of a signalling apparatus, constructed in the.
manner represented in Figure 5, to be used for signalling from the engine
room to the deck of a steam ship, so as to indicate the rate of working and
the direction of the engine's motion, and for other signalling purposes.. I
prefer to employ the condensing and exhausting apparatus, Figures 3 and 4,
for actuating the signalling apparatus Figure 5, but any other suitable condens-
ing and exhausting apparatus may be employed for that purpose. .On the
deck of the steam ship I fix the said signalling apparatus, Figure 5, which
represents a front elevation, with which signalling apparatus the condensing

page_text: and exliausting apparatus, Figures 3 and 4, is connected by means of a pipe;
6 is a dial plate, at the back of which is a chamber divided into two compart-
ments 7, 8, by a diaphragm 9. The compartiment 7 communicates by a
pipe 10 with the condensing and exhausting apparatus, Figures 3 and 4, and
the other compartment S communicates with the atmosphere through the
opening 11. As the air is exhausted or condensed along the pipe 10, it passes
from one compartment to the other over the curved plate or seat 12, in tho
manner indicated by the arrows; the said arrows indicating the direction of
the current when condensed air is forced along the pipe 10. When the air is
exhausted through the pipe 10, tho direction of the current is the reverse of
that indicated by the arrows; 13 is a flap-or plate which turns freely on au
axis, the said flap or plate being suspended over the curved plate 12. The
curve of the plate 12 is of larger radius than the flap 13, and the centre of
the curvature of the plute 12 is situated higher than the axis of the flap 13; so
that when the flap or plate 13 moves in one or other direction out of its
vertical position, the space between its edge and the curved plate 12 is greater
than when the said flap 13 hangs vertically. To the axis of the flap 13 an
index finger or pointer 14. is fixed, and as the condensing and exhausting
apparatus connected with the pipe 10.is worked, the hanging flap:15 is forced
or drawn in one or other direction, and indicates the speed of the engine's
motion by the distance to which it moves the index finger 14. By the
direction in which the index finger 14 moves on one or other side of the zero
point on the index plate, the direction of the engine's motion is indicated.
The condensing and exhausting apparatus, Figures 3 and 4, is geared in any
convenient manner to the ship's engines, so as to make motion therefrom.
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 described and represented in the
Drawing, as the saine may be varied without departing from the nature of
my Invention; but I claim as my Invention, firstly, the improvements in
actuating the moveable arm of railway signals and other signals, in which au
arm or arms are required to be raised and lowered for signalling purposes
berein-before described and represented in Figures 1 and 2 of the accom-
panying Drawing, and the modification thereof herein-before described..
Secondly, making the signal posts of railway and such like signals of a
square hollow tube of iron, one side of which is made into a ladder; and
raising and lowering the signal lamps in the said hollow tubes or posts
by means of a continuous cord or chain passing over pulleys in the said tubes:

page_text: or posts, as herein-before described and represented in Figures 1 and 2 of
the accompanying Drawings. Also jointing signal posts to their base or
foot, as described and represented in the said Figures 1 and 2.
Thirdly, the improvements in ship and other signals herein-before described
and illustrated in Figure 5 of the accompanying Drawing.
Lastly the new or improved condensing and exhausting apparatus herein-
before described and represented in Figures 3 and 4 of the Accompanying
Drawing, to be used in actuating the signals herein-before described, and
such other signals as are or may be actuated by condensed and rarefied air.
In witness whereof, I, the said Charles Pemberton, have hereunto
set my hand and seal, this Eighteenth day of February, in the year of
our Lord One thousand eight hundred and sixty-twō.
Witness,
GEORGE SHAW..
C. PEMBERTON. (L.B.)