IMPROVEMENTS IN SIGNAL APPARATUS CHIEFLY DESIGNED FOR RAILWAYS AND DRAWBRIDGES
Year: 1871

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "IMPROVEMENTS IN SIGNAL APPARATUS CHIEFLY DESIGNED
FOR RAILWAYS AND DRAWBRIDGES."-A communication from abroad by
Thomas Shepard Hall, of West Meriden, Connecticut, and Abram
Lines Van Blarcom, of Summit, New Jersey, both in the United
States of America.
Sealed the 29th September 1871, and dated the 15th August 1871.
COMPLETE SPECIFICATION filed by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 15th August 1871, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN
SIGNAL APPARATUS CHIEFLY DESIGNED FOR RAILWAYS AND DRAWBRIDGES," and
have petitioned Her Majesty to grant unto me, my executors, adminis-

page_text: trators, and assigns, Her Royal Letters Patent for the same, and have
made solemn Declaration that it has been communicated to me from
abroad by Thomas Shepard Hall, of West Meriden, Connecticut, and
Abram Lines Van Blarcom, of Summit, New Jersey, both in the United
States of America.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement, reference being had to the accompanying Drawings forming
a part of this Specification.
This Invention relates chiefly to a system of signals and keys, the
said keys being acted on by the wheels or any part of a locomotive
engine or carriage, and serving to throw an electric current to or from
the signals, which are situated at suitable distances apart on the side of
the railway track in such a manner that by the action of the train
itself the signals are first put on, then kept on till the train has passed
the point of danger, and finally taken off again by the action of the
train. Each train acts on two signals, one behind and the other ahead,
both signals being put on by the action of the train, then kept on for
the proper length of time, and finally taken off again by the action
of the train ready to be acted on by the next train, the said signals
being situated at such distances apart that no train is liable to run
into another, whether the trains run on the same line or track and in
the same direction, or on the same line and in opposite directions.
With the line keys and their connections are also combined crossing
signals to be operated by the action of an approaching train on said
keys in a similar manner to the line signals.
The said Invention relates also to a switch signal actuated by means
of a key connected to the switch rails, and which connects a visible or
audible signal (or both) by suitable line wires in such a manner that
whenever the switch is turned from the main line the circuits through
the magnets operating the signal or signals are closed and the signals
are displayed or set in motion, and as soon as the switch is turned back
to the main line the signals are taken off or stopped.
The said Invention relates further to a drawbridge signal, the action
of which depends upon a key which bears against the lock bolt of the

page_text: draw, and which connects with a visible or an audible signal, or with
both, in such a manner that whenever said lock bolt is moved back the
circuit through the signal magnet or magnets is closed and the signals
are put on and kept on until the lock bolt is returned to its locking
position. In this case the signal instead of being actuated by an
electric current may be made to depend upon its gravity only for its
motio
Figure 1 represents a plan or top view of my line signal apparatus
as applied to a single track or line; Figure 2 is a similar view of the
same when applied to a double track or line.
Figure 3 is a sectional front view of one of the main line signal
houses together with the mechanism for operating the signal or signals
drawn to a larger scale than the previous Figures.
Figure 4 is a detached sectional front view of the double circuit
instrument which forms the main element of the signal mechanism;
Figure 5 is a horizontal section of the same in the plane of the line x, x,
Figure 4.
Figure 6 is a face view of one of the secondary signal houses.
Figure 7 shews a plan of my apparatus as applied to a crossing signal
of a single track or line, drawn to the same scale as Figures 1 and 2;
Figure 8 is a similar view of the same as applied to a crossing signal
of a double track or line.
Figure 9 is a sectional face view of a crossing signal drawn to the
same scale as Figure 3.
Figures 10 and 11 are sectional views of hand keys for raising or
reversing the signals.
Figure 12 represents a plan or top view of my signal apparatus as
applied to a railway switch; Figure 13 is a similar view of the same
as applied to a drawbridge.
Figure 14 is a sectional face view of a signal connected to the lock
bolt of the drawbridge and dependent for its operation upon its own
gravity.
Figure 15 is a side view of the drawbridge at the point of its con-
nection.

page_text: Figure 16 is an inside view of the electro-magnetic signal house.
illustrating the connection of the signal with the battery and line
wires.
In the following description I will first explain the application of the
signal apparatus to a single track or line on which trains run in both
directions. In describing this single track system reference will be
had to Figures 1 and 7 of the Drawings, in which the letter A designates
a single railway track, on one side of which are arranged a scries of
keys a, a, a, a³, a³, a³, a³, a', which have their fulcra on pivots b, and
are in such position that their inner ends are close to one of the rails
and somewhat elevated above the surface of said rail, so that the wheels
of a locomotive or carriage running on the track will depress said inner
ends, and whenever this takes place the outer ends of said keys are
pressed up each between two springs c, c¹, which connect with the line
wires 11, 12, and 13, as shown in Figure 1, that is to say, the springs
of the keys a, a³, a³, and a connect one with the wire 12 and the other
with the wire 13, and the springs of the keys a¹, a³, a³, and a one with
the wire 12 and the other with the wire 11. These wires are supported
on posts B, being insulated from the said posts and from each other in
the usual manner, and their ends extend to and are connected with
signal houses C³, C³, which are situated on the side of the line or track,
and each of which connects by wires 14 and 15 with a secondary signal
house C or C², as shown in Figure 1.
By referring to this Figure it will be seen that these signal houses
are arranged in pairs, which are entirely independent from cach other,
the houses constituting one pair being situated at a distance of two miles
(more or less) from each other.
⚫ The construction of the signal houses and their connections with each
other and with the line wires will be best understood by referring to
Figures 3, 4, 5, and 6 of the Drawings. Each of these houses consists
of a box or casing d provided with an aperture e in the side facing
towards the direction in which the signal is to be displayed. On the
side of the aperture e rises a stud f, which forms the fulcrum for a
lever g, on one end of which is secured the signal disc h, while on its
other is placed an adjustable balance weight p. From the hub of the
lever g extends a chain i to an arm j projecting from a rock shaft k, on
which is mounted a second arm 1, which connects by a rod m with the

page_text: armature lever n of an electro-magnet o. If the armature is attracted
the rod m is forced upward, and the signal lever g is turned on its pivot
so as to bring the signal disc h opposite the aperture e, and consequently
the signal is displayed; but as soon as the circuit of the electro-magnet o
is broken the signal disc, which somewhat overbalances the weight p,
drops back to the position shown in Figure 3, and the signal is taken off.
One end of the helix of the electro-magnet o is in metallic connection
with a wire 16 leading to one pole of a battery D, the other pole of
which connects by a wire 17 with a metallic abutment q. A similar
abutment q¹ connects by a wire 18 with the other end of the helix of
the electro-magnet o, and the two abutments q, q', can be brought in
metallic contact by a key r. If this key is pressed up against both
abutments q, q³, the current of the battery D passes through wire 16 to
one end of the helix o, and through this helix, the wire 18, abutment q¹,
key r, abutment q, and wire 17 back to the battery, the armature of
the electro-magnet a is attracted, and the signal is displayed and kept
displayed until the key r is removed from the abutments. The key r
connects by a lever s* and a rod s with the armature levert of an
electro-magnet u (best seen in Figure 4), and the helix of this electro-
magnet connects at one end with the wire 11, and at the other end with
wires 22 and 19 leading to one of the poles of a battery Dº. The other
pole of this battery is in direct contact with the line wire 12, and if
the line wires 11 and 12 are brought in metallic contact by one of the
raising track keys a³, a², a³, or aⓇ, or by any other means, the circuit of
the electro-magnet is closed, its armature is attracted, the key r is
brought in contact with the abutments q, q', the circuit of the electro-
magnet o is closed, and the signal is displayed. With the signal h is
combined an alarm bell v, the hammer of which is actuated by an
electro-magnet w, the helix of which connects at one end with the
wire 19, while its other end connects with a stud 2*, in which is secured
a spring y carrying the armature z and the hammer 68. The spring y
has a tendency to draw the armature away from the electro-magnet, and
if left to follow its elasticity it bears against a spring c³, which is in
metallic connection with a wire 20 leading to an abutment d² under
the signal magnet o. A similar abutment a connects by a wire 21
with the line wire 12. The abutments & and d² can be brought in
metallic contact by a key e², which connects with and is actuated by the
armature lever of the signal magnet o.
Whenever the circuit through

page_text: this signal magnet is closed the key e² is depressed on the abutments d²
and d, and the circuit through the alarm bell magnet w is closed. The
armature of this magnet is attracted, and the hammer is thrown in
contact with the bell; but as soon as the hammer spring y is thrown
out of contact with the spring the circuit through the alarm-bell
magnet w is broken, the armature falls back, and the contact between
the springs y and c² is restored. The circuit is again closed and the
hammer thrown in contact with the bell, and so on as long as the circuit
through the signal magnet remains closed. When this circuit is broken
the key falls back from the abutments d², d, and as the signal is
taken off the alarm bell ceases to ring. It has been previously remarked
that whenever one of the raising track keys a¹, a², a³, aº, is depressed
the circuit through the electro-magnets u, o, and w is closed, but as
soon as the key returns to its original position the circuit through the
electro-magnet u is broken, and if the armature of this electro-magnet
should be permitted to fall back the key would recede from the abut-
ments q, q', and the circuit through the electro-magnets o and w would
also be broken, or in other words, the signal would be taken off imme-
diately after having been put on, and the alarm bell would cease to ring
immediately after having been started. To prevent this and keep the
signal displayed and the alarm bell ringing until one of the reversing
track keys a, as, a', or a', is depressed I have applied a spring catch
or stop f, which drops in front of the armature lever of the electro-
magnet u as soon as the same has been attracted, and retains the key r
in contact with the abutments q, q', after the circuit through the electro-
magnet u is broken. On the spring catch f² is secured the armature g³
of an electro-magnet h², the helix of which is in contact at one end
with the line wire 13, and at the other end with the wire 19 leading
to one of the poles of the battery D². The other pole of this battery
connects with the line wire 12. If the wires 12 and 13 are brought in
metallic contact, which is done whenever one of the reversing track
keys a, a³, a', or a', is depressed, the circuit through the electro-
magnet h² is closed, the armature 9 is attracted, and the spring
catch releases the armature of the electro-magnet u, the key r
drops back from the abutments q, q', and the circuits through the
electro-magnets'o and w are broken. The instrument which contains
the electro-magnets u and h² and the stop f I term a double-circuit
instrument.

page_text: By referring to Figure 1 it will be seen that the line wires 11, 12, 13,
are connected with one of the signal houses in each pair, that is to say,
with the houses C¹ and C³, and these houses connect by wires 14 and 15
with the houses C and C2 respectively. In order to explain this con-
nection reference must be had to Figure 3, which represents the signal
house C¹ or C or the main signal house in cach pair, and to Figure 6
which represents one of the secondary signal houses. The wire 14
extends from one pole of the battery D¹ and it connects with one end of
the helix of the electro-magnet o* in the house C (Figure 6). The
wire 15 connects with other end of the said helix and with an abut-
ment in the main signal house C¹. A corresponding abutment 221
in this last-named house connects by a wire 23 with the other pole of
the battery D¹. Whenever the armature of the electro-magnet u in the
main house C¹ is attracted a key ³, which is connected to this armature,
is brought in contact with the abutments and ¹, and the circuit
through the electro-magnet o* in the secondary house C is closed, so as
to display the signal and ring the alarm bell (if such is provided) in the
said house. The key is held in contact with the abutments ², 221, by
the spring catch f, and the signals in both houses C¹ and C remain
displayed until the circuit through the clectro-magnet 2 is closed, and
the keys and are permitted to drop back from their respective
abutments.
In Figure 2 I have represented the said system of signals as applied
to a double track or line. The arrows on the tracks indicate the
direction in which the trains run. If a train runs on the track A* its
wheels depress the raising track key a' and the circuit through the
magnets of the signal houses C³ and C2 is closed. The signals of these
houses are immediately put on and kept on until the wheels of the train
depress the reversing track key a', thereby closing the circuit through
the taking off magnet of the signal house C³, and as soon as the armature
of this magnet is attracted, the signals of both houses C³ and C² are
taken off. The signal house C₁ is close to the signal house C2 and im-
mediately after the train has passed the key at it strikes the key a¹ and
the signals of the houses C¹ and C are put on. During the time a train
is between the two signal houses constituting one pair, the signal behind
and that in front are both displayed and no accident can happen from a
succeeding train running into that one ahead except by the grossest
carelessness. The trains ruuning on the track A¹* act on the signals in

page_text: It must
the houses C, C*, in the same manner as above explained.
be remarked that one of the wires 14 or 15 can be replaced by a ground
circuit, so that only one wire will be required to connect the two signal
houses in each pair. In some cases it may be desirable to separate the
bell from the signal house, for instance, in proximity to a station. In
this case a signal house is placed on each side of the station at distances
of half a mile (more or less) from the station house, the signal in
one of said signal houses being put on by the trains approaching the
station on one track and the signal in the other signal house by the
trains approaching in the opposite direction on the other track. The
bell connecting with one signal house is put up at one end of the station
house and that connecting with the other signal house at the opposite
end. As soon as a train passes the signal house, the signal is displayed
and the bell begins to ring, thereby calling the attention of passengers
and of the employès of the road to the fact that the train is approaching.
The signal remains displayed until the train leaves the station, so that no
danger exists that a succeeding train will run into the train stopping at
the station. In some cases it is desirable to put on the signal or to
start the alarm bell by hand. For this purpose hand keys I are usod,
such as shewn in Figures 10 and 11. They consist of two springs c, c¹,
similar to those of the track keys and of a side bolt 2 which is operated
by a rod . Said bolt is subjected to the action of a spring m² which
may be arranged as shewn in Figure 10 where it has a tendency to drive
the bolt up towards the springs c, c¹, or which may be arranged as shewn
in Figure 11, where it has a tendency to drive the bolt away from said
springs. In the former case the rod & serves to retain the bolt against
the action of its spring, and if the rod is released the bolt is brought in
contact with the two springs c, c¹.
In the second case (Figure 11)
the rod serves to draw the bolt down between the springs c, c¹.
The springs c, c³, connect either with the wires 12 and 13, or with the
wires 11 and 12, and by the action of the hand keys the signal can be
put on or taken off at any moment. For instance it may be desirable
to prevent a train from running up to a station while another train is
standing there.
In this case the station master operates the proper
hand key and the signal outside of the station is put on, telling the
engineer of an approaching train to stop.
With the line signals are combined crossing signals as represented in
Figures 7 and 8. the crossing signal as applied to a single track road

page_text: being shewn in Figure 7, while its application to a double track road
is shewn in Figure 8.
In Figure 7, A designates the track which crosses a street G. On one
side of the street near the track is placed a signal house F similar to
that shewn in Figure 3, with the exception that the line wires 11, 12,
and 13 extend out of the signal house in opposite directions as shewn in
Figure 7. With these line wires are combined five track keys a, a¹, a³,
a, a, the keys a, a, a, being raising keys, and the keys a¹ and a³
reversing keys. If a train approaches in the direction of the arrow
marked on the track in Figure 7 it first acts on the raising key a', which
produces no effect, but immediately thereafter it strikes the key a³,
which closes the circuit through the line and signal magnets in the
house F, and thereby the signal is put on. As the train passes the
signal house it strikes the key a² and the signal is taken off, and since
the action of the reversing key a¹ is immediately counteracted by the
raising key a, the signal remains off until a succeeding train arrives. If
the train approaches in the direction opposite the arrow, the effect on
the signal is the same as above described, the keys a and a¹ taking the
places of the key a³ and a*.
In Figure 8 A*, A¹*, designate a double track or line which crosses
a street G. On the side of this street is situate the crossing signal
house F*, the internal arrangement of which is shewn in Figure 9 on
a larger scale than in the previous Figure. On the side of the track A*
are two track keys a, a¹, and on the side of the track A¹* are two other
keys a³, as. The raising keys a¹ and a³ are situated on opposite sides
of the signal house at distances of half a mile (more or less) therefrom,
and the key a¹ connects with the signal house by wires 27 and 28, while
the key a connects with the same by wires 25 and 26. The wires 26
and 28 unite in the signal house or close to it, forming one wire 29.
The reversing track keys'a, a³, are situated opposite the signal house,
and the key a connects with the signal house by wires 30 and 31, while
the key a³ connects therewith by wires 30* and 32. In the interior
of the signal house is the signal h with its magnet o, the alarm bell v
with its magnet w, and two double circuit instruments, one containing
5 the magnets u and h², and the other the magnets u* and **, and both
constructed precisely like the double circuit instrument in the signal
house C (see Figure 3). Two batteries H and H supply the electric

page_text: currents. If a train approaches the crossing on the track A* and the
key a¹ is depressed the circuit through the line magnet u is closed
through wire 27, stud 34, helix a, stud 35, wires 36 and 37, which latter
connects with one pole of the battery H, the other pole of which
connects by wire 38 and 29 and wire 28, which is brought in metallic
contact with wire 27 by the key a¹. The signal h is put on and the
alarm bell started until the circuit through the taking-off magnet h³
is closed, which takes place if the train strikes the reversing track key a
as follows: One of the springs c of the said key connects by a wire 31
with one end of the helix of magnet h², the other end of which connects
by wires 33 and 37 with one pole of the battery H. The other spring c¹
of the track key a connects by wires 30 and 38 with the other pole of
battery H. As soon as the armature of the clectro-magnet h² is
attracted the latch få is released, the key j2 drops back from the
abutments ², 21, and the current through the signal magnet o is broken,
consequently the signal is taken off precisely in the same manner as
in the line signal house represented in Figure 3. The signal magnet o
is operated by the battery H³, and one end of the helix connects by
wire 27 with one pole of the said battery, while the other end of said
helix connects by wires 40, 27, 40, with the abutment 21.
ment ² connects by wires 41, 42, with the other pole of the
The alarm bell magnet to is operated by the battery H, one end of its
helix being connected through stud x, springs y, and c², wires 44 and 44*,
abutments q', q¹*, keys r and 7*, abutments 9 and q*, wires 45 and 45*,
and wire 37 with one pole of the battery, while the other end of the
helix w connects through wires 43, 29, and 38 with the other pole of
the battery H. If a train approaches on the track A¹* the signal is
raised and the alarm bell started by the action of the wheel on the
raising key a³, whereby the circuit through the electro-magnet u* is
closed by wires 25, 46, and 37 and wires 26, 29, and 38, and the signal
is taken off by the reversing key a³ through wires 32, helix h³*, and
wires 47 and 37, connecting with one pole of battery H and by wires
30*, 30, and 38 connecting with the other pole of said battery. If two
trains approach on both tracks nearly at the same time the train first
passing its reversing key must not take off the signal, but the signal a
must be kept displayed until the second train passes its raising key.
The abut-
battery H¹.
This object is effected as follows:-Suppose a train approaches on
track A*, and while this train is running between the track keys a², a³,

page_text: another train approaches on the track A* and passes the raising key a¹
before the first train has reached the reversing key a³. In this case
by the action of the key a¹ the circuit is closed through the helix of
the line magnet u, and the keys j³ and rare held in contact with their
abutments and 1 and q, q'. If the first train strikes the reversing
key a³ the circuit through the taking-off magnet * is closed and the
keys *, * are allowed to fall back from their abutments, but the
keys, r, remain in contact with their abutments; the signal is kept
displayed, and the alarm bell continues to ring until the second train
strikes its reversing key a, whereby the circuit through the taking-off
magnet is closed and the signal is taken off, and the alarm bell
stopped. If there are several crossings not far from each other one
crossing signal house may be put up at a point visible from all the
crossings, while close to each crossing an alarm bell is put, and all
the alarm bells are connected with and operated from the signal house
in the same manner in which the alarm bell is operated.
In Figures 12 to 15 inclusive A designates the main line of a
railroad track which is interrupted either by switch rails B as shewn in
Figure 12 of the Drawings, or by a drawbridge as shown in Figure 13.
The switch rails B Figure 12 connect by a rod a with a key K composed
of a lever b that turns on a pivot c (see Figure 12*), and from which
rises a plug d carrying a metallic projection e that extends up between
the metal plates f, f¹. These plates are insulated from each other and
they connect one with the line wire 11, and the other with the line
wire 12. If the switch rails are in line with the main track the pro-
jection e is in such a position that it does not touch either of the
plates ff, but if the switch rails are turned off from the main. line
the plug d tums on its centre by the action of the lever b and the
projection e is brought in metallic contact with both plates ƒ,ƒ¹.
must be remarked however that other devices might be used to effect
this purpose of closing the circuit through the wires 11 and 12. The
line wires 11 and 12 extend into the signal house D Figure 16, and
the wire 11 connects with one pole of the battery E situated in said
signal house. The wire 12 connects with one end of the helix of an
electro-magnet g, and the other end of this helix connects by a wire 13
with the second pole of the battery E, so that as soon as the wires 11
and 12 are brought in metallic contact with each other by means of
It

page_text: the projection e and plates f,f³, or otherwise, the circuit through the
clectro-magnet is closed. The armature of this electro-magnet
connects by a lever i and rod j with a lever k mounted on a rock
shaft (, from which extends an arm m, that connects by a chain n, with
a pulley o. This pulley is firmly connected to the lever p which carries
the signal q and both the lever and the pulley turn on the same fulcrum
pin 1. A weight & serves to counterbalance the signal q. As soon as
the armature his attracted by its magnet g the signal q is caused to
swing up to a position opposite the aperture t, in the signal house D,
and it is retained in this position until the circuit through the electro-
magnet 9 is broken, which takes place whenever the switch rails are
brought in line with the main track. The signal house is intended to
be situated at the distance of half a mile (more or less) from the switch,
so that an approaching train on passing the said signal house can be
readily stopped before it reaches the switch if the position of the signal
indicates that the switch is not in the correct position. From the
signal house extend wires 14 and 15, to the alarm bell F which is
situated close to the switch and serves to call the attention of the switch
tender to the fact that his switch is not in line with the main track.
The wires 14 and 15 extend from metallic abutments u, u², situated in
the signal house D, and these abutments are brought in metallic contact
with each other by a key v which connects with the armature lever of
the electro-magnet 9 and is pressed up against said abutments whenever
the armature his attracted. When the wires 14 and 15, are thus
brought in metallic contact the circuit of the battery G through the
alarm bell magnet Figure 16 is closed and the alarm bell keeps ringing
until the armature falls back from its electro-magnet g. By these
means all accidents arising from the wrong position of a switch can be
avoided, provided the signals are properly observed. In applying the
signal to a draw bridge C (see Figure 13) the wires 11, 12, 14, 15, the
same signal house D and alarm bell F previously described are used.
The circuit through the wires 11 and 12 is closed by a key w, Figure 13,
the head of which is pressed up against the lock bolt H of the draw-
bridge by means of a spring x. If the lock bolt is drawn back so as to
release the drawbridge the key w is pressed in and the circuit through
the wires 11 and 12 is closed. It is obvious that the construction of this
key can be modified in various ways. It will be found advantageous to
use a key consisting of a plain rod provided with a collar of metal and

page_text: sliding in two standards, one of which is in metallic contact with the
body of the rod while the other is insulated therefrom as long as the
collar is not allowed to come in contact with it. But if the lock bolt
of the drawbridge is drawn back, the collar of the key is pressed up
against the inner standard and metallic connection is established between
the two standards and the wires 11 and 12 which connect with the
same. The lock bolt H is operated by a hand crank a', and it forms
a stop for a shaft b¹ from which extends a rope c¹ to a signal & set
right over the track see Figures 14 and 15. The end of the shaft
is flat and as long as it bears against the lock bolt, the signal d¹ is
kept up.
In the under edge of the lock bolt H is a notch c¹, see
Figure 15, and if said lock bolt is moved clear back this notch comes
opposite the flat end of the shaft 6', and thereby said shaft is released
and the signal & descends. By this purely mechanical attachment the
safety of my apparatus is materially increased, since the signal d¹ will
not stay up unless the lock bolt is brought in its locking position. But
the electro-magnetic signals themselves are a good safeguard against
danger, since the signal in the house D will be kept displayed and the
alarm bell keeps ringing until the lock bolt has been thrown forward
in its locking position, and it can hardly be supposed that the draw
tender would throw the lock bolt in this position unless the drawbridge
is closed.
Having thus fully described the nature of the said Invention, as
communicated to me by my foreign correspondent, and shown how the
same is to be performed, I claim,—
First. The combination of visible or audible signals with raising and
reversing keys actuated by a locomotive or carriage, and with double.
circuit instruments, the said signals being displayed or started auto-
matically by the action of the train on the raising keys, and kept
displayed or in action until the train has passed the point of danger
and then taken off or stopped automatically by the action of the train on
the reversing keys, substantially as described.
Second. The arrangement in combination with a railway track or line
of a series of pairs of signal houses, the signal forming cach pair being
placed at suitable distances apart and connected by wires 14 and 15,
and operated by the action of the trains on raising and reversing keys,
substantially in the manner herein described.

page_text: Third. The arrangement of line wires 11, 12, 13, raising and reversing
keys a, a, a, a³, and signal house C¹, all constructed and operating
substantially as set forth.
Fourth. The combination of the line wires 11 and 12 with the battery D²,
line magnet u, and signal magnet o, substantially as described.
Fifth. The combination of the line wires 11 and 12 with the
battery D³, line magnet u, signal magnet o, and alarm bell magnet w,
substantially as set forth.
Sixth. The catch or latch f2 in combination with the line magnet u,
line wires 11 and 12, key r, abutments q, q', and signal magnet o,
whereby the circuit through the signal magnet is kept closed after
the train has passed the raising key of the line magnet, substantially as
described.
Seventh. The line wires 12, 13, taking off magnet h, and reversing
key acted on by a passing train in combination with the catch or latch ƒ³,
key r, and signal magnet o, substantially as set forth.
Eighth. The line magnet u, key j³, and battery D¹, in the signal
house C³, in combination with wires 14 and 15, and with a magnet u*
in the signal house C, substantially as described.
]
Ninth. The combination with a single railway track or line of a 2
signal house F, wires 11, 12, and 13, extending therefrom in two
directions parallel to the track or nearly so, and keys a, a¹, a², a³, and a",
substantially as set forth.
Tenth. The combination with a double railway track or line of a
signal house F*, wires 25, 26, 27, and 28, and keys a, a¹, a², a³,
substantially as described.
2
Eleventh. The method substantially as herein described of keeping
the signal displayed or in action when two trains approach a crossing
in opposite directions nearly at the same time by means of two double-
circuit instruments connected to the signal or signals, and to the 3
keys a, a, a, a, substantially in the manner set forth.
Twelfth. The hand keys I, constructed substantially as described and
shewn in Figures 10 and 11.
Thirteenth. The arrangement of a key K, connected by a rod > to the
switch rails, and by wires 11, 12, 14, and 15, to the signal house D, and 3
alarm bell F, substantially in the manner herein described.

page_text: Fourteenth. The arrangement of a key w, controlled by the lock
bolt H of a drawbridge, and connected by wires 11, 12, 14, and 15
with a signal house D, and alarm bell F, substantially as herein set
forth.
Fifteenth. The arrangement of a shaft 6¹, controlled by the lock
bolt H of a drawbridge, and connected by a rope c¹ with a signal d³,
substantially in the manner described.
In witness whereof, I, the said William Robert Lake, havo here-
unto set my hand and seal, this Fourteenth day of August,
in the year of our Lord One thousand eight hundred and seventy-
one.
Witness,
E. C. JACKSON.
WILLIAM ROBERT LAKE. (L.S.)