US773025A - Signaling. - Google Patents

Description

PATENTED OCT. 25, 1904.

MILLAR. SIGNALING.

APPLICATION PILEI? OUT. 22, 1902.

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SIGNALING.

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J. MILLAR..

4 SIGNALING.

APFLIGATION IV'ILED OCT. 22, 1902.

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mama-null w mu l PATENTED OCT. 25, 1904 'J. MILLAR.

SIGNALING. APPLICATION HLED 0011222, 1902.

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all semaphores in use at the present time,

U IT D STATES.

Patented October 25, 1904.

PATENT OFFICE.

SIGNALING.

SPECIFICATION forming part of Letters Patent No. 773,025, dated October 25, 1904.

' i I Application filed October 22, 1902. Serial No, 128,275. (No model.)

To all whom) it Weary concern:

Be it known that I, JOHN MILLAR, a subject of the King of Great Britain and Ireland, and a resident of Kearney, county of Hudson, and State of New Jersey, have inventedcertain new and useful Improvements in Signaling, of which the following is a specification.

My invention relates generally to signaling.

and has more particularly. reference to electric semaphores. I

Electric semaphores at the present time are usually operated by a motor to move the signal-arm from the danger or stop position to the clear position or, if it be a three-position signal, to caution and thento clear. When in either position,the signal is controlled by a slot in the form of an electromagnet adapted to be energized and deenergized by the movement of trains over the tracks controlling an armature operating a suitable locking and releasing device. The return movement of the signal-arm to danger is effected be caused by frost or it may be due to the magnetization of the armature. When a con dition of this character arises, the signal is effectually locked in the clear or caution position and cannot return to the-danger position. The seriousness of such a state of affairs will be readily understood; and the chief object of my invention is to produce adevice whereby when this improper adhesion takes place the armature will be automatically forced away fromthe magnet and the semaphore restored to danger by the motor and whereby also the apparatus Will be put in perfect Working order again. The electric semaphore, as just described, serves to illustrate the obj ections which can be raised against Whether they be all electric, electropneu- 'matic, or all pneumatic. In other words, there is no semaphore-signalat the present slot-magnet is energized.

time which will be restored to danger by means of a motor, whether such motor be in the form of an electric motor or an air-pressure device.

As has been stated, the chief object of my terward point out the novel features in the claims.

In my signal the slot-magnet is mounted on a pinion or gear segment, which engages.

with a rack on the signal-rod. This pinion is in engagement with the rack on the rod at all times, so that an unbroken connection is maintained. The said pinion carries an arm the signal-rod there'is located a driving-gear having a pin or other means for engaging with an escapement-lock on the mechanical member of the slot. This driving-gear is placed eccentric with relation to the pinion of the slot.

The motor is started up attheproper time by the passage of a train over the tracks from one block 'to another, thereby rotating the driving-gear. Simultaneously with this the The rotation of the driving-gear causes the pin carried by the same to contact with a primary locking device on the mechanical member of the slot, which moves the armature into contact with the slot-magnet and also moves the escapement-lock of the slot into its locked position. The adhesion of the armature to the magnet prevents the primary locking device of the mechanical member from moving back, and thus keeps the escapement-lock controlled by same in its locked position, so that when the pinof the driving-gear reaches the said escapement-lock of the slot it will carry the latter with it as it rotates, thereby rotating the pinion meshing with the rack on the signal rod, and thus drive the signal to the clear position. If the slot-magnet is not energized, the pin on the driving-gear will escape past the escapement-loek on the slot and the signal will remain in the danger position.

Owing to the eccentricity of the drivinggear with relation to the slot-pinion the pin on the said gear escapes by the escapementlock of and releases itself from the mechanical member of the slot at a certain point, while the said mechanical member engages with retaining means for maintaining it in the position to which it has been carried. The movement of the signal-rod cuts off the inotor, stopping its rotation. A train entering the block controlling the signal will deenergize the slot-magnet, and the mechanical member of the slot will free itself from the retaining means, whereby the signal will be at liberty to drop by gravity, and thus to return to danger.

The signal-rod is provided with two opposed racks, one of which has already been noted as engaging with the slot-pinion. The other of these two opposed racks engages with a restoring pinion carrying a restoring arm. hen a train enters the block and deene'rgizes the slot-magnet, causing the signal to be free to return to danger by gravity, it also puts the motor in circuit. If the signal returns to danger, the movement of same will cut the motor out of circuit again, thus preventingit from starting up; but if the armature should fail to leave the slot-magnet when the latter is deenergized, and thereby prevent the signal from being free to drop by gravity, the motor will start up and the pin or other engaging means on the driving-gear will come in contact with the restoring-arm, carrying the same with it and causing the restoringpinion, which engages with the other of the two opposed racks on the signal-rod, to move the latter down. The movement of the signal-rod will cause the first of the opposed racks to turn the slot-pinion, thus forcing the armature away from the magnet, so as to release the mechanical member of the slot from the retaining means, and in that way to restore the signal-arm to "danger and also to restore the slot to its proper position and the parts to their normal working condition. As soon as the parts are restored the motor is cut out of circuit by the action of the signalrod, thus stopping the said motor. The movement of the driving-gear to carry the signal from danger to clear is equal to half a revolution of the same. hen a three-position signal is used, there will be two retaining means for the mechanical member of the slot, the first for the caution position andthe second for the clear position. In that case the driving-gear will have two pins, one of whlch 1s nearer its center than the other,

and will carry the slot at distance of a. quarter of a revolution, when the first pin will escape past the escapemcnt-loch of the slot and the motor stop. \Vhcn the motor is started up again by the action of the train in the succeeding blocl(, thc second pin of the driving gear will carry the slot another quarter of a revolution and then escape, leaving the signal in the clear position. The return movement to danger is then effected either by gravity or by the restoring device, as previously explained. \Vhen a two-arm signal is used, another slot and restoringmechanism is provided on the other side of the drivinggear, which latter is made to serve for both signal-arms. Only one pin on the drivinggear on each side will then be used. In this case, however, the restoring-arm isprovided with a magnet and a spring to move it into and out of the path of the pin carried by the driving-gear at the proper time, as otherwise the rotation of the gear to operate one signalarm would interfere with the other signal arm. The mechanical member of the slot is constructed in the same way as in connection with the one-arm signal, as the slot will not be carried around with the pin on the gear unless locked by the action of the slot-magnet. Other features of construction and improved combinations and arrangement of parts will be more fully described in the detailed description which follows.

The present application is a sister application to one tiled on the 22d day of October, 1902, Serial No. 128,214, covering my invention broadly and covering also specifically a three-position signal, and is intended to cover the construction of a two-positirm signal of both the one-arm and the two-arm type.

in the drawings I have embodied my invention in a suitable form; but changes may of course be made within the scope of the claims.

In the said drawings, Figure 1 is a general viewofasignalembodyingmyinvention. Fig. 2 is an enlarged view of the driving-gear, slot, connection for the signal-rod, and supplementary devices, showing the parts in the position occupied by them when the signal is at danger and when theslot-magnetis deenergizml, another slot mechanism being indicated in dotted lines back of the driving-gun. Fig. 2 is a sectional View through the escapementlock on the line .2 of Fig. 3. Fig. 3 is a side view of Fig. 2. Fig. 4 is a detail view of the. ordinary restoring mechanism. Fig. 5 is a detail view of the restoring-arm used on the two-arm signals. Fig. 6 is a diagrammatic view showing the signals in three blocks and the wiring and circuits used in connection with my invention.

Similar letters of reference indicate corresponding parts in the ditierent views.

A is a motor having a non-reversible arma ture and provided with the armaturc-shaft a. F indicates a signal-rod to which the motion of this motor is imparted at the proper mounting the different parts of the slot. The.

times through the instrumentalityof suitable means, as the driving-gear O and the slot The signal rod carries a semaphore of the usual construction, counterweighted so as towhich rises on both sides of the saididrivinggear from the base D; In the present form the semaphore will conveniently be operated through one of two opposed racks f and f whose faces turn away from each other, attached to the signal-rod F. To correspond with this construction, a pinion or gear seg ment 6' is provided. The slot mechanism as a wholeis indicated by the reference-letter E and is conveniently carried by the said pinion e, which carries a rigidly-fixed arm and extension 6 provided at its upper end with the cross-piece 6 which forms a support for slot proper comprises an escapement-lock a,

clock-springe. To transfer the motion of I the driving gear to suitable mechanism or means for operating the signalrod,'such as the pinion e and the rack f, I provide a pin 0" on the-said gear and attach a projection 0 on the said escapement-lock, with which the said pin is adapted to engage. The pinion e is mounted eccentric with relation to the gear C for reasons which will hereinafter appear.

e is theslot-magnet, conveniently mounted on the pinion e and controlling-the armature 6 mounted loosely on one side of the pin 6 The escapement-lod; is further provided with a notch e, with which engages the dog a, alsoloosely mounted on the pin 0, so as to move independently of the .armature. This dog has the effect when the magnet is energizedof holding the escapement-lock rigidlyl by engaging in the notch e of the latter, so that when the gear C turns and the pin 0 engages with the projection e the pinion 0 will receive the motion of the said gear, thereby operating the signal-rod. To prevent undue movement of the escapement-lock, the latter is provided with a stop a engaging with the.

pin 0 on the extension 6*. 1

e is a retaining-lock in the form of a member 6 mounted on the pivot e of the escapemept-lock e and carrying the yielding projection e" by the spring 0 Gr is a notched standard with which the said retaining-lock will engage when the pinion a has beenturned a suflicient distance. At that point the pin 0 will escape past the projection 6 of the escapement-lock owing to the eccentricity ofthe-pinion e with relation to the driving-gear. The

signal has now been moved from danger to clear and the action of the motor'will therefore cease. The slot and magnet beinglocked, as the magnet is still energized, will prevent the return of the arm. When the next train comes along and moves into the block controlling the s'aid signal, it will short-circuit the track-circuit anddeenergize the magnet, so that'the escapement-lock is no longer held in its rigid position by the dog 0 but is held yieldingly only by the spring e The counterweight of the semaphore will therefore be free to act upon the escapement-lock, which turning upon the pivot 6 will free the retaining-lock from the retaining means or notched standard G, thereby permitting the rack f to drive the pinion a, carrying the slot, back to its original position. To effect the initial or primary movement of the armature into contact with the magnet, I provide a primary locking device consisting of two jaws 6 one of which carries the friction-roll 6 attached to the pivoted armature, and the intermediate member 6 pivoted at 0 and located substantially'at right angles to the armature and engaging with the jaws e of the same by means of the arm 6 to turn the armature on the pivot 0 e is an arm moving with the member 6 and adapted to be engaged by the pushingpin 6, which in turn is operated by the pin 0 to move the armature into contact with the magnet through the above means prior to the said pin 0 reaching the projection e. If the magnet is not energized, the armature will of course move away from the same again as soon as the pin 0' is past the pushing-pin a so that the escapement-lock will not be held rigidly by the dog 6 thereby allowing the said pin 0 to escape past the projection 01. The dog a is controlled by the armature by means of the cam 6 moving with the intermediate niember 6 on which cam rests the roll 0 of the arm 6 moving with the dog a. In this vway the armature and magnet will control the dog a through the escapementlock 6 so that after the magnet is energized and the armature has been moved into contact with the same the connection between the driving-gear and the means for operating. the signal-rod is controlled absolutely by the said magnet and armature and the slot cannot be released except by deenergizing the magnet. The reasonvfor using this double: lock slot is to distribute the strain more evenly. If, for instance, thedog and the armature 63 were mounted so as to move in unison by being both fast on the pin 6, the strain would fall on this pivot only. By interposing the intermediate member 6 and arm 6 1 can get the, benefit of two levers, which tends to distribute the strain. j

G is a notched standard placed. a distance away from the. danger position of the slot substantially equal to a semicircle, forming retaining means to engage with the retaininglock on the slot.

H is a restoring device in the form of a pinion ]L, engaging with the rack f of the signalrod and provided with an arm or member, as if, which is moved into the path of the pin 0 when the signal is in the clear position and out of the path of the pin when the slot is restored to the danger position.

When a two-arm signal is used, it is convenient to operate both arms from the same motor and from the same driving-gear. To this end a second slot mechanism substantially like the one previously described is placed on the other side of the driving-gear, which latter in this instance is provided with a second pin 0 on its other side. One modification, however, is necessary when this construction is usedviz., the restoring-arms, which must be so arranged that the driving-gear can retate and operate one arm without interfering with the other. This is accomplished by providing the restoring-pinion it with an arm 725, pivoted at its center at 7& and held normally out of the path of the pin 0' or 0 by the spring if, while it is moved into the path of the pin by the restoring-magnet it at the proper moment when the said magnet is energized.

The opposed racks f and f may be carried by the signal-rod or by a connection or extension of same. In the'present instance they are carried by the connection f adapted to be secured at f to the signal-rod proper and connecting at its lower end with the pistonrod z" of the dash-pot I. The base I) is secured removably to a hollow support (Z and carries the dash-pot I, which is removably secured to the said base and projects inside the hollow support. By disconnecting the signal at f and the coupling 6 of the shafts a and Z) the entire operating mechanism can be removed and replaced, which is of great advantage.

In connection with a two-arm signal two dash-pots I will of course be used, and when the signals and armature-shaft are disconnected the base D can be turned around on the hollow support (Z by sliding the said base on the track (Z so as to make all the parts easily accessible for cleaning and repair. To facilitate matters, the base is provided with a spring-seated pin or catch cl", whichengages with apertures (Z* and (Z opposite to each other, so that when the base is turned it will stop after a half of a revolution, thereby gaging the position of the mechanisms carried upon the said base accurately.

In Fig. 6 is shown a diagrammatic view of the signals in three blocks, together with the wiring and circuits for operating the mechanisms properly, a train being indicated in the last block.

In each signal the motor is connected with the battery J at all times by the wire j, while j, termil'iating in the electrode j".

the slot-magnet is connected with the said battery through the wire j.

K is a relay energized by the track-circuit coming from the battery J and controlling the finger j, forming a switch connected with the battery J through wire j. \vhen the relay is deenergized, the linger j is in contact with the electrode j of the wire j, terminating in the electrode j and when the relay is energized it attracts the linger j and moves it into contact with the electrode/ connecting with the slot-magnet, thereby putting the said magnet in circuit, and also with the wire The linger f is connected with the motor by means of the wire j and is adapted to be operated mechanically between the two electrodes f and j by the fluctuation oi the signal-rod.

*hen the signal is at clear, the linger j will be in contact with the electrode j, so that the slot-magnet is in circuit, thereby maintaining the slot locked, so that the retaining-lock a is held in engagement with the notches on the standard (1? while the motor is out of circuit, owing to the fact that the tingen/ has been moved into contact with the electrode f by the fluctuation ol the signalrod F. As a train now enters the block it short-circuits the track-circuit of the l, attery J, thereby deenergizing the relay K, causing the arm j to drop into contact with the electrode/ This, it will be observed, puts the slot-magnet out of circuit, thereby releasing the slot and leaving the signal tree to return to "danger by gravity, and puts the motor in circuit. If the signal returns to danger by gravity, the movement ol the signal-rod will cause the linger j to move into contact with the electrode 1' thus putting the motor out of circuit; but if the armature refuses to leave the slot-magnet, and thereby maintains the signal in the clear position, the motor, beingin circuit, will start up and the pin r", coming in contact with the restoring-arm l1, will cause the pinion /z,' to move the signalrod down, the power breaking the arn'iature away from the slot-magnet, thus restoring the signal to danger. The motor then stops, being cut out of circuit by the movement of the signal rod as just described. The train upon leaving the block and entering the one next succeeding causes the trackcircuit to be restored, energizing the relay K, bringing the arm f in contact with the electrode j, thus putting both the motor and the slot-magnet in circuit. the motor starts up, the pin 0 will engage with the primary locking device, pushing the pin against the arm 0 thereby causing the armature to move into contact with the slot-magnet and the dog 0 to lock the escapement-lock e". As the gear C rotates, the pin c will next ei'igage with the projection a of the escapement-lock, causing the rotation of the pinion 1/ and the fluctuation of the signal-rod.

This movement will continue until the signal has been driven to the clear position, when, owing to the eccentricity of the gear and thepinion carrying the projection e the pin 0 will escape past the latter and the retaining-lock 0 engage with the notched standard G, causing the signal to be maintained in the position to which it has been moved. The movement of the signal-rod F in carrying the signal from danger to clear will cause the arm to moveinto engagement with the electrode y", thereby putting the motor out of circuit, while leaving the slot-magnet in circuit, so as to maintain the slot locked. The signal then remains in this position until another train enters the block and releases the slot.

When two arms are used, the wiring just described will operate the upper or danger arm S, while the lower or caution arm is controlled by asecond finger, f, of the relay K, one finger lying behind the other, and a second arm, like J controlled by the movement of the signal-rod of the signal S. A wire similar to i (denoted by the referenceletter 7' and provided with the electrodes 7' and is adapted to make a circuit from the second finger, 7' through the second arm, to the motor. The slot-magnet of the second arm, S, is connected with the battery by the wire 7'. From the motor runs another wire, terminating in the movable electrode 1' which isadapted to move with the upper or danger arm S and when the latter is at clear to come in contact with the electrode 1' of the wire 1', connected by the wire 7 with the slot-magnet of the caution arm S and terminating at its other end in the electrode or finger From the electrode 1 runs a wire terminating in the electrode 7 K is a second relay, connected by line-wires j and 1' with the battery J of the succeedclear position, a train on entering the block ing block, the circuit to energizethe said relay being closed through the electrodes 1' and 7' when the danger-arm S of the said succeeding block moves to clear, thereby putting the motor and theslot-magnet of the cautionarm S in circuit to drive the said cautionarm S to clear. As will be remembered, when two signal-arms are used the restoringarms of the slots are provided with electromagnets 72 The electromagnets are bothconnected by the wires and with the electrodes 7' and j and by means of the wires and with the wire 7'.

Assuming now that both arms are in the will short-circuit the track-circuit from the battery J, thus deenergizing therelay K, causing the two fingers f to move into contact with the electrodes 3' and 1' As the signal-arms are in the clear position the fingers 1' will be in contact with the electrodes and j" The closing of the circuits at 7' and ff" therefore deenergizes bothslot-magnets and puts both restoring-magnets and caution positions, respectively, and cut the motor and restoring-magnets out of circuit again, as previously described. Likewise if either arm should fail to' return to the horizontal position the motor would start up and, owing to the restoring-magnets, would drive the proper arm to its upper position. Upon the train leaving the block the track-circuit will be restored, reenergizing the relay K and moving the fingers f into contact with the electrodes 1' and f thereby putting the slotmagnet of the danger-arm S and the motor in circuit, thus driving the said danger-arm to clear. In so doing the electrode is moved into contact with the electrode The slot-magnet of the caution-arm S, however, is not put in circuit, as the relay K has been deenergized by the danger-arm in the succeeding block going to danger, whereby the electrodes j andj are brought out of contact with each other. When the train enters the third block, the relay K is energized by the action of the danger-arm S in the second block going to'clear, thereby closing the circuit at and. This moves the finger f into contact with the electrode thus putting the slot-magnet of the caution-arm S and the motor in circuit and driving the said caution-arm S to clear. From this it appears that the two slot-magnets are put in circuit successively and that they are put'out of circuit simultaneously and the restoring-magnets putin circuit simultaneously.

It will of course be understood that the system of wiring can be changed very materially so long as the motor-slots and restoring-magnets are put into and out of circuit at the proper moment. Obviously the signal can be used both on the normal danger and normal safety plan by. changing the wires to correspond therewith. Instead of line-wires the s c-called wireless system could be used.,,

' The various mechanisms comprising the slot,

driving-gear, motor, &c., will, as is usual, beinclosed in a suitable casing, and the signalrod will preferably be inside a hollow iron signal-post. In place of the gear C a simple disk could be used, and other engaging means instead of the pin could of course also be employed. last in a train of gears; but the construction shown here is very much preferable, 'as with a worm and worm-gear an even and steady Thegear C could of course'be the also be used will break the circuit for the motor as soon i as the armature leaves the signal, or it can be constructed so that it will not break the circuit until the semaphore-arm has assumed the horizontal position.

Having thus described my invention, what I claim is 1. In a signal, the combination with a semaphore counterweighted so as to have a bias to the danger position, of a motor, a slot, a slot-magnet, a restoring device operated by the motor, connections and circuits for putting the slot-magnet and motor in circuit to drive the semaphore from the danger position to clear, and for putting the motor out of circuit when the said semaphore arrives at clear, the slot and magnet when locked, preventing the return of the semaphore, and for putting the slot-magnet out of circuit to allow the semaphore to return to the danger position by gravity, and for putting the motor in circuit to restore the semaphore to danger through the instrumentality of the restoring device in case the said semaphore is not restored to danger by gravity when the magnet is put out of circuit.

2. In a signal, the combination with a semaphore, having a danger and a caution arm, counterweighted respectively to the danger and caution positions, and a motor, of a slot, a slot-magnet, and a restor ing device operated from the motor, for each signal-arm, connections and circuits for moving the said arms separately and respectively from danger and caution to clear, each slot and magnet when locked preventing the return of its respective arm and each restoring device restoring its respective signalarm to danger and caution if the slotmagnet, when deenergized, fails to release its signal-arm so as to allow it to return by gravity.

3. In a signal, the combination with a semaphore, having a danger and a caution arm, counterweighted so as to have a bias re- 4s I n spectively to the danger and caution positions, and a motor, of a slot, a slot-magnet, a restoring device operated from the motor, and a restoring-magnet, for each signal arm, connections and circuits for putting the slot-magnet of one of said arms and the motor J in circuit to drive the said arm from the danger position to clear, and tor'putting the motor out of circuitwhen the said arm arrives at clear, for putting the slot-magnetol the other arm and the motor in circuit to drive the said other arm from the :aution position to clear, and for putting the motor out of circuit when the said other arm arrives at clear *each slot and magnet when locked preventing the return of its respective arm for putting the two slot-magnets out ol circuit to allow the arms to return to the danger and caution positions respectively by gravity, and for putting the two restming-magnets and the motor in circuit, each restoring device restoring its respective signal-arm to danger or caution" ii the slot-magnet fails, when deenergized, to release its signalarm so as to allow it to return by gravity.

In a signal, the combination with a semaphore, having a caution and a. danger arm, counterweighted so as to have a bias respectively to the caution and dangel positions, and a motor, having a non-reversible armature, and rotating in one direction only, of a slot, a slot-magnet, a restoring device operated from the motor, and a restoring-magnet, for each signal-arn'i, connections and circuits arranged so that when the slotmagnet of the danger arm is energized, the rotation of the motor moves the said arm from the danger position to clear, and whereby the continued rotation of the motor when the magnet of the caution arm is energized, moves the said caution arm from caution to clear, each slot and magnet when locked preventing the return of its respective arm, and each restoring device restoring its respective arm by the further rotation of the motor if the slot-magnet fails, when deenergized, to release its signal-arm so as to allow it to return by gravity.

5. In a signal, a driving-gear, a drivingpinion engaging with a rack of the signal-rod, a slot mounted on the driving-pinion comprising a magnet, an armature, an escapementlock, a primary locking device, an intermediate member forming a double locking means from the armature to the escapement-lock when the magnet is energized, m mns carried by the driving-gear for engaging with the primary locking device to cause the armature to contact with the magnet and the escapement-loch to be locked and for subsequently engaging with the escapcment-lock thereby turning the pinion a certain distance moving the signal from danger to clear, the arrangement being such that the m ans carried by the driving-gear releases itself from the escapement-lock when the signal has attained this position, and retaining means for preventing the return of the signal to danger so long as the magnet remains energized and to maintain it in the position to which it has been carried.

6. In a signal, a driving-gear, a drivingpinion placed eccentric of' same and engaging with a rack of the signal-rod, a slot mounted on the plIllOn comprising a magnet, an armature, an esoapement-lock, a primary locking device, an. intermediate member forming a double locking means from the armature to the escapement-lock when the magnet is energized, and a retaining-look, a pin carried by the gear to engage with the primary locking device to cause the armature to contact with the magnet and the escapement-lok to be locked and for subsequently engaging with the escapement-lock thereby turning the pin-' ion adistance equal to one-half of a revolution thereby moving the signal from danger to clear, the pin escaping past the retaininglock owing to the eccentricity of the pinion with relation to the'gear when the signal has attained this position, a notched standard. to engage with the retaining-look to prevent the return of the signal to danger so long as the slot-magnet is energized and for maintaining it in the position to which it has been carried.

7. In a signal, the combination of a gear, a signal-rod having a rack, a pinion engaging with the said rack, a restoring-lever pivoted JOHN MILLAR.

Witnesses:

JOHN D. KNoTT, AXEL V. BEEKEN.

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