A METHOD OR METHODS OF MAKING SIGNALS BY SELF-ACTING APPARATUS TO BE USED ON RAIL- WAYS, FOR THE PURPOSE OF OBVIATING COLLISIONS BETWEEN SUCCESSIVE TRAINS
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
BERWICK CURTIS, of Acton, in the County, of Middlesex, Esquire, send
greeting.
WHEREAS I did by Petition humbly represent unto Her present mošt
Excellent Majesty Queen Victoria, that I had invented "A METHOD OR
METHODS OF MAKING SIGNALS BY SELF-ACTING APPARATUS TO BE USED ON RAIL-
WAYS, FOR THE PURPOSE OF OBVIATING COLLISIONS BETWEEN SUCCESSIVE TRAINS,"
and Her said Majesty, being willing to give encouragement to all arts and
inventions which may be for the public good, was graciously pleased, by Her
'Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Nineteenth day of
January, One thousand eight hundred and forty-one, in the fourth year of Her
reign, for Herself, Her heirs and successors, to give and grant unto me,
the said Charles Berwick Curtis, my exors, adiñors, and assigns, Her especial
licence, full power, sole privilege and authority, that I or they, by myself or
themselves, or by my and their deputies, servants, or agents, or such others
as I or they should agree with, and no others, during the term of fourteen
years from the date of the said Letters Patent, should and lawfully might
make, use, exercise, and vend my said Invention within that part of Her
Majesty's United Kingdom of Great Britain and Ireland called England, the
Dominion of Wales, and Town of Berwick-upon-Tweed, in such manner as to
A

page_text: me, my exors, admors, and assigns, should seem meet, and that I and they
should enjoy the whole profit and advantage arising by reason of the said
Invention during the said term of fourteen years; and for that end Her snid
Majesty required and strictly commanded all her subjects whatsoever, within
England, Wales, and Berwick-upon-Tweed aforesaid, that they should not,
neither directly or indirectly, make, use, or put in practice my said Invention,
or any part thereof, nor in anywise counterfeit, imitate, or resemble the same,
nor make any addition thereto or subtraction therefrom, whereby to pretend
himself or themselves to be the inventor or inventors thereof: And whereas
the said Letters Patent contain a proviso obliging me, the said Charles Berwick
Curtis, particularly to describe and ascertain the nature of my Invention, and
in what manner the same is to be performed, by an instrument in writing
under my hand and seal, and to cause the same to be inrolled in Her Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said Letters Patent, as in and by the same (reference
being thereunto had) will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Berwick Curtis, do hereby declare that my said Invention is described
and ascertained in manner following, and by the aid of the two Sheets of
⚫ Drawing hereunto annexed; that is to say :-
My method or methods of making signals by self-acting apparatus, to be
used on railways, for the purpose of obviating collisions between successive
trains, consists or consist in applying over, above, or else close by the side of
a line or pair of rails of a railway, at any suitable place along the course of
such line or pair of rails, an apparatus of one or other of the kinds herein-
after particularly described; which apparatus, without requiring any manual
. direction, exhibits a signal whenever a train in travelling along the said line
or pair of rails to which such apparatus is applied arrives at or opposite to
and passes beneath or by the side of the said apparatus; and which apparatus,
. on the passing of such train; immediately exhibits some very visible signal,
which cannot be overlooked or fail to be seen by the driver or person who
directs the progress of a succeeding train, in case the same should be travelling
or following too closely after the first-mentioned train along the same line of
rails and in the same direction, so as to arrive at or near to the apparatus
whilst such signal continues to be exhibited thereby; and the said signal being
:seen by such driver, will inform him that he is not to proceed, but is to stop
his train, for the purpose of obviating collision with the said first-mentioned or
preceding train. And after such visible signal has been so exhibited during an
adequate interval or space of time for allowing the said preceding train to
:
1

page_text: have travelled forwards or advanced along the line so far or such a distance
beyond the place of the apparatus thereon as that a succeeding train may be
allowed to follow after a preceding train without a decided risk of collision
therewith, then the said signal is withdrawn gradually out of sight by means
of wheelwork which the said apparatus contains, that wheelwork being
actuated by what is called a maintaining power of a weight or a spring, and
the wheelwork being allowed to commence moving by virtue of that main-
taining power at the time when the apparatus exhibits its signal as aforesaid:
1;
and the said signal will, by the motion of the said wheelwork, be withdrawn by
degrees out of sight, or else into a position which will produce another change
of its appearance, denoting inaction or rest; and during the time whilst it
is so withdrawing, the said signal will (after some certain time has elapsed
since the apparatus has first exhibited its signal) change its appearance in
some very marked manner, so as to constitute a different signal, which cannot
fail to be seen by the driver of the succeeding train before mentioned, in case
the same (instead of arriving at or near to the apparatus, as herein-before
supposed, during the time whilst the signal continued to be exhibited in its
first mentioned manner) should arrive thereat later and during the time that
the apparatus exhibits the aforesaid changed appearance of such signal, and
which being seen by such driver, will inform him that he ought not to proceed
at full speed with his train, but should advance slowly, in order to avoid
following too closely after the preceding train; and by the time that the signal
exhibited by the apparatus is wholly withdrawn out of sight, in consequence of
the gradual action of the wheelwork in inanner aforesaid, or else is withdrawn
into a position denoting inaction or rest, then the motion of that wheelwork
will cease, and the apparatus will be out of action, and it will continue out of
action, with its wheelwork motionless, until the passing of another train along
the rails, when the apparatus will immediately exhibit its signal in the manner
already mentioned, and will also after due time begin to withdraw that signal
by the motion of its wheelwork; and the signal, whilst withdrawing, will
change its appearance, and will ultimately be wholly withdrawn out of sight
or into its resting position, and then the motion of the wheelwork will be
stopped again in manner above described, and a repetition of such action will
take place by every successive train which arrives and passes under or. by the
apparatus. And in case that all the successive trains which are travelling along
the line on which the apparatus is situated keep true to their intended times of
arrival respectively at the apparatus, as appointed for each train, so that they
will all follow duly one after the other at sufficient distances apart to avoid
danger of collisions between the successive trains, then in such case the

page_text: signal that is exhibited by the apparatus immediately after one train has
passed will be wholly withdrawn out of sight, or will be withdrawn into its
resting position before the next succeeding train arrives at the apparatus, and
the driver of that train will not see any signal at all, or will-see the signal in
its resting position, denoting inaction of the apparatus. But the absence of any
signal, or the inaction of the apparatus, informs him that a sufficient time has
elapsed since the preceding train passed the apparatus, and therefore he may
proceed with his train at its usual speed without fear of overtaking such
preceding train and coming into collision therewith. And when the said
succeeding train passes the apparatus, it thereupon exhibits its signal imme-
diately, in the same manner as was done at the passing of the preceding train;
and also, after due lapse of time, that signal is.withdrawn, in manner before
mentioned, wholly out of sight, or into its resting position; and the next suc-
ceeding train ought not, in due course, to arrive until after the said signal has
been so withdrawn so as to be no longer visible, or to be in its resting position.
But in case any train should be following more closely after its preceding train
than it is intended to do, so that it will arrive at the apparatus so soon after
or within such a space of time after its said preceding train had passed the
apparatus as to incur any risk that the said preceding train might be over-
taken by the before-mentioned train which is following after it, and so cause
collision between them, then in such case the driver of such train which is
following too closely will, when he approaches the apparatus; see the signal in
the changed appearance which the same exhibits when it has become partially
withdrawn, in manner before mentioned, by the motion of the wheelwork of
the apparatus; and on seeing such signal in its said changed appearance, the
driver will know that he ought not to advance at full speed, but only slowly,
as already mentioned. But in case the said train is following so much too
closely after its preceding train that it will arrive at the apparatus in such a
short space of time after its said preceding train had passed the apparatus
as to be actually in danger of overtaking and coming in collision therewith,
then the driver of such train which is following so much too closely will, when
he approaches the apparatus, see the signal exhibited thereby in its first
appearance, and will thereby know that he ought not to proceed at all with his
train, but is to stop the same; and wait a due time before he passes the
apparatus, in order to give time for the preceding train to advance to a proper
distance forward before he sets out to follow after it; and whether it be that
the succeeding train is following too closely, or more closely than is intended,
after its preceding train, in consequence of the preceding train having set off
too late, or having failed to make due progress on its journey, so as to have

page_text: •
got behind its proper appointed time of arrival at the apparatus, or whether it
be in consequence of the succeeding train having set off too soon, or having
travelled too fast, so as to have got before its proper appointed time of arrival
at the apparatus, or whether it be in consequence of both these causes con-
jointly, nevertheless, the operation of the apparatus will in either case be the
same as above described, because the operation of the apparatus has no
relation to any hours or times of the day or night when trains ought in due
course to arrive at the apparatus; but whenever any train has passed by the
apparatus, it puts the same in action, whereby it immediately exhibits its
signal, and, after being so put into action, the wheelwork of the apparatus in
due time gradually withdraws the said signal out of sight, or into its resting
position, and then the motion of the wheelwork stops, as already stated; and
the whole space of time during which the apparatus continues thus in action,
and whilst the wheelwork is so engaged in withdrawing the signal, that is to
say; from the time that signal is first exhibited until it is finally withdrawn to
its resting position, is the shortest space of time that ought in prudence to be
allowed to intervene between the passing of one train and the passing of
the next succeeding train, in-order to avoid any risk of the latter overtaking
the former, so as to cause collision between them. And a series of such appa-
ratuses as herein-before mentioned being placed at intervals along the line
of the railway, all that has been herein-before stated will be true in respect
to each of those apparatuses; that is to say, such an apparatus as before
mentioned is to be applied at each place along the line of the railway where it
may be thought most requisite or desirable, so as by means of a number of
such apparatuses to establish a series of signals at suitable intervals along the
line, for the purpose of enabling the driver of every train which is travelling
along the line to know, by seeing the signals of the 'several apparatuses in their
resting positions, as he comes in sight of them one after another, that the train
which has preceded him has passed by each apparatus so much sooner before
his arrival thereat as that the said preceding train will have had ample time to
have got on so much before him as to avoid any risk of his overtaking and
coming in collision therewith; or if at any part of the journey the said
succeeding train should be getting to follow too soon after the preceding train
.to be quite safe against the risk of collision therewith, then the driver of that
succeeding train will be informed of the circumstance by seeing that the signal
of the next apparatus which he comes to after having so got too soon is only
partially withdrawn, and is exhibiting its changed appearance before men,
tioned, and thereby he knows that he ought to slacken the speed of his train
in order to allow more time for the preceding train to get in advance of him;

page_text: or if at any time he is getting to follow so soon after the preceding train as to
be in any decided danger of overtaking the same, he will be informed of that
circumstance by seeing the signal- of the next apparatus fully exhibited, and
not begun to be withdrawn, in which case he ought to stop and wait awhile,
as herein-before stated. And each of the two lines or pairs of rails of the
railway is to be furnished with its own series of apparatuses, in manner
aforesaid, the several apparatuses belonging to each line or pair of rails being
disposed along the side thereof, so as to render their signals distinctly visible to
the drivers of the trains in advancing along the said line towards the several
apparatuses, which will in turn be put in action by such trains as they pass by
the several apparatuses.
.
And as to the sort of signals that are to be exhibited in manner aforesaid,
according to my said method or methods, the same may be varied to accom-
modate to the custom established for each railway whereon the method is
adopted. For instance, a red-colored signal, or red-colored lamp at night,
being already used as indicative of danger on some railways, the same red
colour may be adopted for the signal which is to be exhibited by each
apparatus immediately after a train has passed by that apparatus, as before
mentioned; and that red may be made to change to a green colour, or to
point to such a colour during the withdrawing of the signal, so as to produce
the changed appearance thereof before mentioned; and when wholly with-
drawn to its resting position, the signal may change to a white or clear light,
or be made to point with white on a black ground, all which is only
mentioned by way of example.
DESCRIPTION OF THE DRAWINGS representing Different Kinds of Apparatus
which may be used in the Manner and for the Purposes herein-before
mentioned.
In Sheet I. Figure 1 is a transverse elevation, and Figure 2 is a longitu-
dinal elevation, of an apparatus which may be applied at any bridge which
crosses over the railway, A being one of the side pieces, and B part of the
arch of such bridge. C, C, is a pair of rails constituting one line of the rail-
way whereon the locomotive engine D of a train of carriages travels, and that

page_text: thereof, in order to reach towards the side piece A of the bridge, and which.
axis d is sustained in suitable bearings fixed upon a sleeper of wood or upon.
blocks of stone, set firmly in the ground, or in the ballasting of the railway;.
and from the said horizontal axis d a short lever arme (see also Figure 4).
extends horizontally towards the pier A of the bridge, and an upright rod f,.
which is jointed to the end of the said lever arm e, is carried up by the side of
the pier A of the bridge, being supported in guides g, g, which are affixed to.
the said pier. The upper end of the rod f is connected by a short oblique links
h with the lower or tail end of a lever i, whereof the centre pin or fulcrum.
is sustained in a bearing bracket k fixed fast to the pier A, and the upper end.
of the lever i is bended round into what may be called a goose neck, the.
extreme or upper end of which applies to the central part of one of the.
wheels of the wheelwork belonging to the apparatus,, that wheel marked-j
being, in fact, only three radial arms of a wheel without any circular rim.
thereto. The action of the said parts is as follows:-When the piece of wood.
a is carried by the advancing motion of the locomotive engine over and in
contact with the curved lever arm or trigger b, the latter is pressed down, and
by means of the axis d, and its lever arm e, the rod f is thereby lifted or moved
upwards endways in its guides 9, 9, and that motion, by means of the short
link h, causes the lower end of the lever i to be moved outwards from the
pier A of the bridge, and, consequently, the upper end or goose neck i will
be moved towards the said pier; and in so doing the extreme or upper end of.
that goose neck i will press backwards the central part of the said external.
three arms or wheelj of the wheelwork. The said action is almost instanţa-
neous; for as soon as the engine has carried its piece of wood a over in contact
with the curved summit of the trigger b, and beyond that summit, then the said.
trigger b, being left at liberty again, is immediately borne upwards by action of.
a balance weight 1, whereby the rod f is drawn downward or allowed to
descend, and the oblique link h withdraws the goose neck from its said contact
with the central part of the three arms j, allowing the same to come forwards.
And note, in order to ensure that the goose neck shall not fail to come for-.
wards, a spring m is applied to act behind the goose neck. The three arms
or wheel j is mounted externally on a projecting square at the end of a hori-
zontal axis belonging to the wheelwork, and which axis is turned slowly and
steadily round with a revolving motion by the wheelwork whenever the same.
is in motion, by action of its maintaining power of weight or spring, as
before mentioned.. And by the said square the three arms j are then carried.
round with a corresponding revolving motion; but the said three arms ; admit
of being slided backwards along the square whenever the goose neck i presses.

page_text: back the central part of the three arms, as above described. And there is a
spring formed of curled wire applied around the said axis behind the central:
part of the three arms j, so as to urge the same forwards along the square of
the axis, whenever the goose neck i will permit the three arms; to come
forwards. The wheelwork of the apparatus is enclosed within a box E, which
is let into the pier A or into the arch B of the bridge, and fixed firm to serve
as a box for the wheelwork, which is mounted in a framework of its own, that
frame. being enclosed to form a case, which is inserted into the fixed box E,
and fits therein, so that the wheelwork is effectually shut up and protected; but
nevertheless, the whole of the wheelwork in its said case can easily be with-
drawn from the fixed box E, in order to get at the wheelwork when requisite,
and then after examination it can be replaced into the box E; or in case the
wheelwork is formed to require cleaning or repair, then a duplicate of the
same wheelwork, having its own framework and case complete, can be put
into the fixed box E into the place of that which is so withdrawn, and will
operate in the same manner and in lieu thereof. And it is desirable-that the
wheelwork with the framework and box thereof, for the several apparatuses
which are set up at different places along the line of the railway, should be all
alike, so as to be exact duplicates one of another, in order that any wheel-
work with its own case may fit into the fixed box E of any of the said appa-
ratuses, and therefore, by having some supernumerary wheelworks and cases,
any wheelwork which may require cleaning or repair can be promptly
removed and replaced by another wheelwork without hindrance to the
required operation of the apparatus. The three arms j operate on the signal
F by means of a pin projecting out horizontally from the front surface of each
arm near to the end of that arm, and as the three arms revolve, those pins
are carried round in a circular orbit, and one of them after another reaches
over and takes: hold of and presses down the tail or short end n of the lever
n, p, G, at the long end G of which lever the signal F is sustained, so as to
move up and down, the signal F being set in a border frame formed at the
said long end G of the lever n, p, G, and the signal F itself consisting of
coloured glass or other suitable material set in that border frame in the manner
of a window pane. An upper portion of the signal F may be, as represented
in the Drawing, red-coloured glass, with the remainder or lower portion green-
coloured glass, and the border frame of the signal (which frame determines
the form of the signal, may be of a circular form, as represented in the
Drawing, or may be a square, or lozenge, or diamond, or hexagon, or triangle,
or any other form that may be preferred. The lever n, p, G, of the signal F
is poised upon a horizontal centre pin at p, which pin may be fixed firmly to

page_text: the pier A or arch B, or to a projecting part of the fixed box E, so as to
project forward horizontally, and it serves as the centre of motion of the lever..
J is a counterbalance weight fixed on the tail end n of the lever, and capable
of being fastened thereon farther from or nearer to the centre of motion p;
so as to counterpoise a part of the weight of the signal F, but, never-
theless, leaving the same with a sufficient preponderance to cause it to
descend, when permitted, with a moderate rapidity of descent into the
position represented in Figure 1, whereby the signal becomes exhibited.
But the action of the three arms j, when the same revolves, is to carry
round one of its aforesaid pins into contact with the upper edge of the
tail of the lever, and then the said pin, by pressing down that end in
of the lever will cause the long end G.thereof, and the signal F, to be
raised up with a slow and very gradual motion, so as to withdraw the
signal F, by raising it up behind a fixed screen H, I, K, by which it will be
concealed from view, as is shewn in Figure 3. The said screw H, I, K is
fixed by its uppermost border, and its two side borders, against the vertical
face of the pier A or arch B, so as to leave a sufficient space clear of the pier.
or arch for the signal F to pass up behind the said screen and the pier or arch
without touching either. When the said pin in the three-arm j bas thus
pressed down the tail end n of the lever so low as to have raised up the signal
F behind the screen H, I, K, and thereby withdrawn the same wholly out of
sight, as in Figure 3, then the said tail end n comes down to rest on a stop r;
which prevents any further motion of the lever n, p, G; and the further
motion of the said pin in the three-arm j being also prevented, in consequence
of its contact with the end n of the lever, the motion of the wheelwork becomes
stopped, and then the apparatus continues motionless in the position repre-
sented in Figure 3, which is its resting or inactive position, herein-before
mentioned, and which denotes that so much time has elapsed since any train
has passed by or under the apparatus that the said train has had ample timė
to get on in advance of any succeeding train which may arrive at or in sight of
the apparatus after the signal F has been so withdrawn into its said resting
position, Figure 3, and therefore the driver of such succeeding train, on
finding the signal so withdrawn, may proceed therewith at the usual full speed
of travelling, without risk of overtaking the preceding train, so as to come
into collision therewith. And when such a succeeding train passes by or
beneath the apparatus, the aforesaid piece of wood a that is carried by the
locomotive engine of that train will pass over and press down the trigger b,
and by means of the axis d, the short lever e, upright, rod f, link h, and the
goose neck, the upper end of the latter is caused to press back the three-

page_text: arm j, in the manner already described, and thereby that pin in the said three
arm which has been hitherto holding down the tail end n of the lever, as
appears in Figure 3, is carried so far backwards that the front end of the said
pin will quit the lever entirely, and leave the same at liberty, and then the
preponderating weight of the signal F will cause it to descend immediately,
in order to exhibit the signal F, the tail end n of the lever at the same time
moving upwards before the end of the said pin in the three-arm j, without
touching that pin or being obstructed thereby. The signal F descends by its
own weight all at once into the position Figure 1 in order to exhibit the signal;
but owing to the effect of the counterpoise J, the descending motion of the
signal F is moderated, and it is stopped in the position Figure 1 by the tail
end n of the lever coming against a stop s, and a suitable fixed stop may
also be provided beneath the signal F, or beneath the long end G of the lever,
in order to assist in stopping the signal F steadily in the position Figure 1,
without rebounding therefrom. Note, the action of the goose neck i to push the
three-arm backwards is only instantaneous, as already explained; and as
soon as ever the train has passed by, the three-armj is brought forwards again
by action of its own curled wire spring, before described as being applied
behind the centre of it; and as soon as the said pin in the three-arm j becomes
liberated from the tail end of the lever n, in consequence of the three-arm j
having been pushed backwards for an instant, and then the said tail end
beginning to move upwards at that instant in manner above described, then
the wheelwork is no longer prevented from moving, and therefore the same
immediately commences its motion by action of its own maintaining power of
a weight or spring. The three-arm j is thereby turned slowly and steadily
round, and the next succeeding or uppermost pin in the said three-arm j advances
in its circular orbit towards the end n of the lever; but the said pin takes some
time to get round into contact therewith, and during all that time the signal
is left quite motionless in the position Figure 1, that is to say, fully exhibited,
denoting (as already explained) that any succeeding train which may arrive at
the apparatus whilst the signal is so exhibited is to stop and not to proceed.
And when the said pin in the three-arm j has got round to the tail end n of the
lever, it comes in contact with and presses upon the upper edge thereof, and by
slowly-pressing down that tail or short end n, the signal F at the long end G
of the said lever is raised,up so as to be gradually withdrawn behind the screen
H, I, K, as already explained, until all the parts regain the resting position,
Figure 3, and then the tail end n of the lever, having come down to rest
against the stop r, is prevented from moving any farther, and thereby the
wheelwork, being also prevented from moving further for the present, its

page_text: motion ceases, and the apparatus continues in its said resting position,
Figure 3, until it is again brought into action by the passing of another
succeeding train, which will act by its piece of wood a upon the trigger b, as
already described. The signal F, when fully exhibited as in Figure 1, shews
its whole form, and the red color at the upper part of it is fully exposed to
view. Also the front surface of screen H, I, K, may be painted with three
colors, as represented in Figures 1 and 3, and a short bended arm may be
extended upwards from the top of the border frame of the signal F, and after
coming forwards through a curved slit t in the screen, the said arm, making
another bend, may have a pointer or small signal L fixed to the end of it, so as
to be held in front of the screen H, I, K, and the said pointer L will move
upwards and downwards at the same time with the signal F. The said pointer
L may be of a circular form, or other form corresponding to the form of the
principal signal F, and may be of a white colour in order to shew clearly
against the colors on the front of the screen H, I, K, when the signal is fully
exhibited, as in Figure 1. The pointer L will shew itself upon the red color
at the lower portion K of the screen H, I, K, indicating the red-coloured
signal, in order to correspond with that which is at the same time visible at
the upper part of the signal F, and at night or in hazy weather a lamp or
other light is to be applied behind the upper portion of the signal F, at the
place shown by the dotted circle N, Figure 1. That light N (see also
Figure 3) may be placed in a suitable recess in the pier A or arch B, so that
it will shew a red-colored light when the signal F is fully exhibited, as in
Figure 1, in consequence of the red glass at the upper portion of the signal F
being then immediately in front of the light. Such lamp or light may be of any
of the kinds which are or may be used for or be suitable for signal lights on
railways, with any adequate reflector. or lens; but the lamp of itself must be
adapted to give a clear white light, which only becomes colored in consequence
of the signal F being interposed in front of the light whenever the signal F is
exhibited; and by degrees, as the signal F is raised slowly upwards by action
of the wheelwork in manner aforesaid, the red-colored portion of the signal
will ascend above the light, so that it will by degrees cease to show the red
colour, but the green-coloured portion of the signal F will be. brought opposite
to and in front of the light, which will then begin to shew a green-coloured
light, in order to produce the changed appearance of the signal herein-before
mentioned, such change being from red color to green, if the apparatus is
constructed as is represented in the Drawings; and at the same time the
pointer L will be opposite to and in front of the green colour at the middle
portion I of screen.H, I, K, and therefore in the daytime the said pointer L

page_text: .will shew itself against that green colour, denoting the aforesaid changed
appearance of the signal; and any train which may happen to arrive at or in
-sight of the apparatus whilst the signal is exhibiting its said changed appear-
Fance (which in the present instance is its green colour); such train is not to be
allowed to proceed at its ordinary full speed, but only slowly, as herein-before
explained; and by the time that by the gradual action of the wheelwork, as
already explaineil, the signal F is quite raised up into its resting or inactive
position, Figure 3, so as to be wholly withdrawn and hidden behind. the
screen H, I, K, then the pointer L will be opposite to and in front of the
black colour at the upper portion H of the screen, and the light N, Figure 3,
will shew its own clear white light, free from any colour, because the signal F
is no longer interposed in front of the light. Note, the piece of wood a,
which is applied to the locomotive engine of the train, is suspended on a centre
>of motion in a forked iron R, which is fixed to the frame of the engine, and
descends therefrom. The under side of the piece of wood' a is a curved form,
in order that it may not act too abruptly upon the trigger when it comes in
'contact with .and passes over the same; the upper surface of the trigger b,
twhich is to be so acted upon, is also curved. The piece of wood a, by being
*suspended, will be able to accommodate itself to the trigger, which only
*requires to be pressed down a small distance in order to produce the required
effect of causing the goose, neck i to push back the three-arm j so far as to
carry the pin of the three-arm j back behind the end n of the lever, as
. álready described. The motion of the piece of wood a, about the centre on
which it is suspended in the fork R, is limited by stops to a small extent of
motion, in order to prevent unnecessary swinging of the piece a. The fork R
is fixed to the frame of the engine, so as to hold the piece of wood a no
farther out sideways beyond the width of the rails than the steps of the carriages
"extend out sideways, and the under side of the piece of wood a must be at
such height as will be suitable for acting properly on the trigger b, in order to
**press the same down in passing over it. The trigger 6 must be low enough
down to avoid being touched by any of the steps of the carriages.. The
*.triggers 6 of all the several apparatuses at different places along the railway
must correspond precisely one with another as to height above the level of the
rails, and as to distance sideways, therefrom; also the pieces of wood a of all
the several engines which are employed on the railway must be fixed thereto,
- so as to correspond one with another, so as that every engine will be duly
**qualified for acting properly and similarly upon all the triggers. The piece of
wood a at R will, be operative when the engine is travelling in the most usual
'manner, with its tender. following after it; but a similar piece of wood a may

page_text: be applied at the opposite side of the engine, as shown by dotted lines S;'
Figure 1, in order to be ready for opérating whenever the engine is required"
to travel with its tender foremost; and as to the wheelwork of the apparatus,
the same may consist, as represented in Figure 2, of a spring barrel v, which
by a chain or catgut pulls round a fusee w, together with a main cog wheel;
the teeth of which turn those of another cog wheel of about two thirds the
size of the said main wheel. The end of the axis y of that wheel & projects'
out in front of the frame and case of the wheelwork, in order to carry the
three arms j, which are fitted upon a square at the front end of the said axis y,"
so as to be turned round therewith; but, nevertheless, the three-arm j is
capable of being pushed backwards along the said square end of the axis y
by action of the upper end of the goose neck i pressing against the central
part of the three-arm j, as already explained; and the spring of curled wire'
which is applied behind the central part of the said three-arm; acts to push
the same forwards upon its square on the axis y as far as it is permitted to
come forwards thereon by a stop pin, which is fixed across the axis, with its
ends projecting out therefrom into slots through the central part of the three-
armj; and when the same is so come forwards, then the pins of the three-
arm will intercept and act upon the short end n of the lever. And note, in
order to retain the said end of the level in due position in respect to the said
pins, it is guided laterally between a pair of fixed curved arches r, s, Figure 1;
at the ends whereof are the stops rand-s before mentioned, for limiting the
motion of the lever. And note, in order to obviate the effect of wind blowing
against the signal F, a similar curved arch may be fixed behind the border of
the signal F, which may have small rollers to bear against such guide, in
order to sustain the signal F laterally, and yet so as to allow it to move with
but little friction as it goes up or down; and for every train which passes by the
apparatus, the pin of one of the three arms j must come into operation, and
the axis y must make one third of a revolution, so that for every three trains
which pass it must make a whole revolution; and in case the cog wheel on the
axis y has two thirds as many teeth as the main cog wheel of the fusee, the
latter will unwind at the rate of one revolution for every four and a half trains
which pass, and therefore if the chain or catgut makes twelve turns around
the fusee, so that the wheelwork requires twelve turns for winding the same
up, then once winding up will serve for the passing of fifty-four trains beforó
it requires winding up again. These numbers are only stated by way of
example, as they must be accommodated to suit the extent of traffic on thé
railway to which the apparatus is applied. The wheelwork should be wound
up once in every twenty-four hours, and should be qualified to serve for as

page_text: many trains as can ever be expected to pass during thirty-six hours. As to
the force of the maintaining or main spring of the wheelwork, the same will
require to be stronger than those usually employed in clockwork, and must be
adapted to suit the size and weight of the signal which is to be exhibited, the
wheelwork having in all cases ample power to control that weight and give the
required motion to the signal for raising and withdrawing the same without
any risk of stopping or pausing in so doing. And for regulating the motion
of the wheelwork, the cog wheel before mentioned on the axis y turns a
pinion on an axis x, having about one tenth part of the number of the teeth
in that said wheel, and on the axis a is a cog wheel turning a pinion on an
axis n, having about one eighth part of the number of the teeth in that
wheel; and on the axis n is also fixed an escapement wheel, having about nine-
teen serrated teeth, which operate by turns first an uppermost tooth, and then
a lowermost tooth of the said escapement wheel on the two pallets of a ver-
tical axis, the upper end whereof carries a heavy balance or fly z, which is
turned about one third round alternately backwards and forwards in the manner
of the vertical escapement and balance of a common pocket watch, except
that there is no pendulum spring, and the weight and size of the balance. <
must be adapted suitably in order to retard the motion of the wheelwork to
the required slowness, so as that the whole space of time of turning the axis y
and the three-arm.j one third of a revolution will be about ten minutes of
time, and about one third or one fourth of that whole space of time may be
expanded after the wheelwork has commenced its motion, but before the
uppermost pin in the three-armj gets round so far as to carry its pin into
contact with the end n of the lever, in order to begin to raise up and withdraw
the signal F from the position Figure 1, and the remaining three fourths of
that space of time being expended in raising and withdrawing the signal F
from its position, Figure 1, to its resting position, Figure 3. But these
periods are only stated by way of example, for it is obvious that the space of
time during which the signal should remain fully exhibited, as a Figure 1, and
then the further space of time during which it should be gradually withdraw-
ing into the resting position, Figure 3, must depend on the ordinary rapidity
of travelling along the railway; and also in each apparatus the said times
must be regulated in some degree to suit the particular part of the railway
whereon the apparatus is placed, whether it be on a level part, or at the foot
of an ascending plane, or at the summit of a descending plane, and also to
suit the inclination of such planes, the said times being, in each case, suited
to the circumstances, so that every train which has passed by the apparatus,
and put the same into action and exhibited the signal, shall have had time to act

page_text: As
so far forwards as to be out of danger of being overtaken by a succeeding
train before the said signal is withdrawn to its resting place, Figure 3.
to the size of the apparatus, the same may be larger or smaller, as required.
The signal F should be large enough to be very distinctly visible, and should
move up and down rather more than the height or diameter of the signal F.
Note, the wheelwork and signal part of the apparatus in Figures 1, 2, and 3,
is drawn on a scale of one twelfth part of the real size; but in order to avoid
needless extension of the Sheet of Drawing, the locomotive engine, and the
trigger b, with its axis d, short lever e, rod f, and goose neck i, are drawn on
a much smaller scale, being about one sixteenth part of the real size, and
therefore the lower parts do not appear in the proper proportion with the
upper part of the apparatus. Hence the signal F appears to be situated imme-
diately over the chimney of the engine, which it ought not to be, and will not
be in fact, although it will be as well to have the signal reach a little way
over the rails; and in cases where a bridge does not occur over the railway,
at a place thereon where an apparatus ought to be situated, any suitable post
and frame may be erected to sustain the apparatus. And note, instead of a
spring barrel and fusee for the maintaining power to actuate the wheelwork, a
weight suspended by a cord wound up around a cylindrical barrel in place of
the fusee may be used, such weight being enclosed within a tall upright box
or trunk, on the top of which is the fixed box E to receive the wheelwork, as
before described, but which box cannot in such case be inlaid into the pier
or arch of the bridge, but must stand projecting out therefrom, together with
the signal F and its screen H, I, K. The upright trunk which receives the
weight may serve as the post of the frame to support the apparatus, and it
may be a hollow column. The winding up of the maintaining power of the
wheelwork may be done once in every twenty-four hours by means of a key,
in the usual manner of like kinds of wheelwork.
Figures 5, 6, and 7, Sheet II., represent a different kind of apparatus, as
to the appearance of the signal which it exhibits, although the wheelwork and
the operation thereof are the same as already described. Instead of the
signal being a circle or other figure borne at the long end of a lever arm, the
signal is in the shape of a sector or fan, as is shewn detached in Figure 7, the
whole surface of such sector being exhibited from the circumference or arm F
nearly to its centre of motion p, which answers to the centre of motion of the
lever n, p, G, in the apparatus, Sheet I., the whole of the sector F, G, being
poised on that centre p with a counterbalance-J, on a short tail Y, at the
opposite side of the centre. The sector is wholly enclosed within a box or
case V, which is supported on the top of a standard, and is adapted to contain

page_text: the sector, and to permit of its notion about its centre p, the extent of that
motion being the same in angular measurement as that of the signal in Sheet I.
In one side of the box V is a triangular opening through which the sector can
be seen, in order to exhibit its signal, as in Figure 5. The said opening may
be glazed with window glass, to obviate the effect of the wind, the outer-
most portion of the sector at F glass set in a border frame, the upper part
being red-colored glass, and the lower part green glass, and does not differ
from the signal, Sheet I., except in form, being exhibited as a square instead
of circular. The innermost portion G of the sector F is a frame, over which
colored cloth or other suitable material is stretched or fixed. E is the box
'containing the wheelwork, which, together with the goose neck i, and trigger b;
*with its axis d, short lever e, and upright rod f, are all the same as in Sheet I.
The three-arm j operates upon a short tail n, projecting downwards from the
centre of motion p, and operates in the same manner as the corresponding
part in Sheet I., the difference in the position of the centre of motion p with
respect to the centre of the three-arm j making no difference in the operation.
'N is the lamp, which may be applied to a slider, which is fitted to run up à
pole, by means of a rope and pulley, when required.
Figures 8, 9, and 10,-Sheet II., explain how a similar self-acting apparatus
to that herein-before described may be applied to exhibit signals of that kind
which are commonly fixed on the top of a tall pole Z, set up in the manner of
'an upright axis on a pivot T at the lower end, and sustained in a vertical
position by a fixed collar at P, Figure 8, so as by turning the said pole or axis
Z one quarter round about on its said pivot T, the large circular signal F, on
the upper end of the pole Z, will be exhibited; but when the pole is turned
back again through that quarter of a circle, then the said circular signal F
will be exhibited edgeways, but an oblong signal Q, which is fixed on the top
of the pole immediately beneath the circular signal F, and crossways thereto,
will then become exhibited instead of the circular signal F. The self-acting
apparatus for exhibiting signals by such a turning pole may be made on the
same construction as that in Sheet I., except as to strength and force of the
wheelwork and lever, with its counterweight, which must be much stronger, to
*suit the resistance of turning a tall poll Z, with large signals like F and Q on
the top of it, than in Sheet I., and will therefore be more suitable to be
actuated by a weight than by a spring for its maintaining power. The lever
n, p, G, Figure 8, in place of having the signal itself at the long end of that
lever, as in Sheet I., has a heavy weight U fixed upon it, which is allowed to
descend all at once in the same manner as the signal does in Sheet I. when a
strain -passes by the apparatus and it exhibits a signal. The lever G, n, p, is

page_text: mounted on a horizontal axis (see the Plan, Figure 9), from which a bevel-
toothed sector W ascends upwards so as to work in the bevel teeth of a
smaller sized sector, or rather quadrant, X, which is fixed on the pole or
vertical axis Z, below the collar P thereof, so that the two sets of bevel teeth
W and X will gear together, and cause the pole to be turned round one
quarter of a revolution, when the lever G and sector W move one third as
much, or one twelfth of a revolution, and thereby the pole will exhibit one of
the two different signals F or Q, denoting a signal that any train arriving
whilst it is exhibited is to stop, and the other denoting that such signal is
withdrawn, which, however, is done by degrees as the weight U is raised up.
The wheelwork is enclosed in a box E, which box is fixed by brackets to one
A lamp
of the posts for sustaining the pole Z, as is represented in Figure 8.
with three lenses, whereof one colored red, the next green, and the third
without colour, may be applied to the pole Z by drawing it with a cord and
pulley up a vertical guide rod fixed at one end of the pole Z, the three lenses
of the lamp radiating the light in three different angular directions, the red
lens being in the direction to be exhibited along the line of the railway at the
same time that the oblong signal Q is cxhited, and the white lens being
exhibited when the circular signal is exhibited, then the green lens will be
exhibited in the intermediate position between those two former, in order to
serve for the changed appearance of the signals. And note, the aforesaid
mode of exhibiting signals, by means of a pole turning as a vertical axis, forms
no part of my Invention, and is only introduced here to shew how the same
may be actuated, in the manner herein-before described, by the application of
my self-acting machinery thereto.
Having now described my said method or methods, I, the said Charles
Berwick Curtis, do hereby declare that the new Invention, whereof the
exclusive use is granted to me by the said Letters Patent, consists in the
method or methods herein-before described of making signals by the self-
acting apparatus herein-before described, to be used on railways for obviating
collisions between successive trains; the distinguishing character of which
apparatus is, that at every time when a train travels along that part of the
railway where any such self-acting apparatus is situated, so as to pass by that
apparatus, the same will exhibit a signal immediately on the said train so
passing by such apparatus, and will continue to exhibit the said signal without
alteration in the appearance thereof, so long as there will not have been suffi-
cient time for the said train to have advanced far enough along the line beyond
the said apparatus to permit of any succeeding train to follow after the said
first-mentioned train; and the signal so exhibited will give information to the
B

page_text: driver. of any such succeeding train which may happen to come up in sight
of the apparatus that he is to stop, and not proceed; and which apparatus,
after having so exhibited such signal, then in due time begins to withdraw the
same gradually from full view by the motion of self-acting wheelwork, as
herein-before described, and whilst so withdrawing the said signal is caused to
change its appearance in some marked manner, as herein-before described,
in. order to give information to the driver of any train which may happen to
arrive within sight of the apparatus, whilst the signal is so exhibiting in it's
changed appearance, that such train may proceed slowly, but not at full speed.
And the said apparatus, after having so exhibited the signal in its said changed
appearance, also wholly withdraws the signal from view, or withdraws the same
into an inactive or resting position, and then the motion or action of the appa-
ratus ceases, and, it continues in its inactive or resting position until another
succeeding train passes; and the signal in its acting or resting position serves
to inform the driver of any such succeeding train which may happen to arrive
in sight of the apparatus, when in that state, that he may proceed at full speed
without risk of collision with the preceding train.
In witness whereof, I, the said Charles Berwick Curtis, have hereunto