AN IMPROVED ELECTRIC COMMUNICATION BETWEEN RAILWAY TRAINS IN TRANSIT OR OTHERWISE, AND SIGNALS, STATIONS, OR TERMINI, AND IN THE APPARATUS EMPLOYED THEREFOR.
Year: 1874

page_text: LETTERS PATENT to Sir David Lionel Salomons, Baronet, of Broom
Hill, Tunbridge Wells, in the County of Kent, for the Invention of
"AN IMPROVED ELECTRIC COMMUNICATION BETWEEN RAILWAY TRAINS IN
TRANSIT OR OTHERWISE, AND SIGNALS, STATIONS, OR TERMINI, AND IN THE
APPARATUS EMPLOYED THEREFOR.
"
Sealed the 15th January 1875, and dated the 13th October 1874.
PROVISIONAL SPECIFICATION left by the said Sir David Lionel
Salomons at the Office of the Commissioners of Patents, with his
Petition, on the 13th October 1874.
I, Sir DAVID LIONEL SALOMONS, Baronet, of Broom Hill, Tunbridge
Wells, in the County of Kent, do hereby declare the nature of my said
Invention for "AN IMPROVED ELECTRIC COMMUNICATION BETWEEN RAILWAY
TRAINS IN TRANSIT OR OTHERWISE, AND SIGNALS, STATIONS, OR TErmini, and in
THE APPARATUS EMPLOYED THEREFOB," to be as follows:-
The Invention is designed for the purpose of enabling the conductors
of a railway train or carriage to communicate through the medium of
electricity with persons in authority at stations or termini on the line
A

page_text: of route on which such train or trains may be travelling, or to enable
one train to communicate with another, whether travelling or stationary
on the same track, or by suitable electro-magnetic arrangements to place
danger signals in position, which will warn a train in the rear or advance
of the one signalling of its position or proximity thereto, and finally
through the medium of such electric communication to actuate auto-
matically apparatus in connection therewith which will transmit motion
to levers and rods on the engine and train that will partially or wholly
shut off the steam and simultaneously therewith apply the breaks, and
again when required take them off.
The first portion of this Invention relates more particularly to the
arrangement of apparatus forming electric communication between the
trains and the signal boxes, signals, and stations on the line of route,
the novelty of which consists in providing the permanent way with an
intermediate or third rail; or an electric wire distended on insulating
supports in a position which will admit of one or more metallic bowls or
wheels connected with the train to run thereupon in a manner which
will allow a constant and perfect electric contact to be maintained there-
with when required. The running bowl or wheel is provided with
insulated electric conductors communicating with a galvanic battery,
"Gramme's electric machine, or other electric apparatus placed in the
guard's van or other suitable position about the train or line, so that at
the time the periphery of the bowl or wheel is running upon the sup-
porting wire an electric communication will be established between such
train and any other train signal, signal box, station, or termini supplied
with suitable electrical apparatus on the same line of route, enabling
thereby persons in charge of a train to communicate with other persons
in charge of trains, signals, stations or termini situated at points on the
line of route whether in advance or in the rear of the train transmitting
the message, or vice versa.
Secondly. The improvements relate to a novel arrangement of
apparatus in connection with the foregoing electrical apparatus which
will enable a train to act automatically upon another train or signal on
the same line of route in manner following:-The permanent way at
suitable positions and distances apart is provided with an arrangement
of levers and sliding bolts carrying tappets which can be retained or
released so as to be placed in a desired position or be withdrawn there-
from by an electro-magnetic or mechanical arrangement of apparatus in

page_text: connection with the rail or wire through which the electric current is
discharged. The trains on the line of route are provided with apparatus
communicating with the shut off valve and whistle of the locomotive,
and also with an arrangement of electric, pneumatic, or steam break.
The rod communicating motion to the aforesaid apparatus is placed
directly over and in a line with the movable tappet of the electro-
magnetic or other apparatus before mentioned, these movable tappets
when in their normal position are out of the way and clear of the rod
transmitting motion to the apparatus connected with the running trains,
but in the event of any person in authority at a station, signal box, or
on another train requiring that a train at some distance when passing a
given point shall have its steam shut off and breaks applied auto-
matically, then and in such case any one of the persons in authority as
aforesaid discharging an electric current to such point will place the
sliding tappet in position ready to act on the passing train in the manner
aforesaid. The signals also on the line of route, are provided with
electro-magnetic apparatus which will enable them in like manner to be
acted upon by trains or from stations at a distance through the medium
of their electric connection for the purpose of placing such signals "at"
or "not at danger."
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Sir David Lionel Salomons in the Great Seal
Patent Office on the 13th April 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Sir DAVID
LIONEL SALOMONS, Baronet, of Broom Hill, Tunbridge Wells, in the
County of Kent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirteenth day of October, in the year
of our Lord One thousand eight hundred and seventy-four, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said Sir David Lionel Salomons,
Baronet, Her special licence that I, the said Sir David Lionel Salomons,
Baronet, my executors, administrators, and assigns, or such others as
I, the said Sir David Lionel Salomons, Baronet, my executors, adminis-
trators, and assigns, should at any time agree with, and no others,
1 2

page_text: from time to time and at all times thereafter during the term therein
expressed should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "AN IMPROVED ELECTRIC COM-
MUNICATION BETWEEN RAILWAY TRAINS IN TRANSIT OR OTHERWISE, AND SIGNALS,
·STATIONS, OR TERMINI, AND IN THE APPARATUS EMPLOYED THEREFOR," upon the
condition (amongst others) that I, the said Sir David Lionel Salomons,
Baronet, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and.
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Sir David Lionel Salomons, Baronet,
do hereby declare the nature of my said. Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
The first portion of the Invention is designed for the purpose of
enabling the conductors of a railway train to communicate through the
medium of electricity with persons in authority at stations, termini, or
signal boxes on the line of route on which such train or trains may be
travelling. Or to enable one train to communicate with another,
whether travelling or stationary on the same track, by means of suitable
electro-magnetic arrangements actuating signalling bells and indicators
which will warn a train in the rear or advance of the one signalling of
its position or proximity thereto.
Secondly. The Invention relates to an arrangement of apparatus in
electric connection with that of the first part before mentioned, which
when put in action will automatically, partially, or wholly shut off the
steam of the engine and simultaneously therewith apply the breaks, and
again when required take them off and turn on steam.
The first portion of this Invention relates more particularly to the
arrangement of apparatus forming electric communication between the
trains and the signals or stations or other points on the line of route, the
novelty of which consists in providing the permanent way with a third
or electric rail laid in sections or blocks or other electric medium, each

page_text: "
section or block at its commencement and termination overlapping so as
to run in parallel lines and in a position which will admit of metallic
signal wheels connected with the engine and train, as herein-after
described, to run thereupon in a manner which will allow a constant and
perfect electric contact to be maintained between the trains and such
clectric or third rail. The signal wheels are insulated from each other
and from the engine and are provided with insulated electric conductors,
one communicating for instance with a battery composed of "Leclanche"
cells, and the other with an electric bell, one wire from each (viz), the
"battery" and the "bell" are taken to "earth" by simply being:
attached to the engine. These wheels will herein-after be called,
"battery signal wheel" and "bell signal wheel." When one wheel.
only is in contact with the single electric rail the circuit is incomplete
or "open," and also when both wheels are running on their respective
rails, but when such insulated rail is "put to earth by its connection
therewith through the medium of another train entering the same block
or by a "key," then the circuit is complete or "closed" so that signalling
can be effected with any other train on the same block either before or
behind or with any signalling apparatus in electric connection with the
electric line of rail. Again, any train being at an intermediate distance
between the two blocks with its battery signal wheel only in contact
with the electric rail its signals or electric apparatus would be actuated
and communicated with immediately another train entered the same
block, as the current would be put to "earth" and so complete the
circuit of electricity by reason of the break or disconnection of the
electric rail, thereby effecting communication with electric indicators or
signals placed in the guard's van which give timely warning to both.
trains of their proximity to cach other; or such electric signals can be
communicated with by persons in authority at signal boxes or stations:
through the medium of a "key" which puts the current to earth so as
to complete the circuit, as herein-after described. At level crossings, that.
is, when horses and carriages cross the line, or other similar places on the
line of rails where it would be inconvenient to maintain the continuous
line of rail for a short distance the continuity of the electric medium
could be effected by connecting the separated ends of the rail by means
of an insulated electric wire carried under ground; or if desired the con-
nection between the rails if separated for long distances could be effected.
by means of a wire supported on poles in a position which would allow
two wheels having similar connections and used for a like purpose as

page_text: the lower "battery signal wheel" and "bell signal wheel" to run
thereupon.
Secondly. The trains on the line of route are provided with electric
apparatus communicating with the shut-off valve and whistle of the
locomotive, and also with an arrangement of electric, pneumatic, or steam
break herein-after described.
In order that the Invention may be well understood and explained in
detail, I have hereunto annexed two Sheets of Drawings, in which
Figures 1, 2, 3, 4, 5, 6, 7, 8, and 9, illustrate as examples in detail the
various arrangements of parts shewing how the first portion of my In-
vention can be carried into practical effect; and Figures 10, 11, and 12
of the second Sheet illustrate as examples and in detail how the second
portion of my Invention can be carried into practical effect, similar
letters of reference being marked on corresponding parts on all the
Figures alike.

page_text: circuit, and Figure 9 represents an arrangement of armature and magnet
which I term a "key," for enabling a person in authority at a signal
box or station to form contact with the electric rail, and so com-
municate with a train at a distance by putting the current to "earth"
so as to complete or "close" the electric circuit.
As the foregoing Figures are those which relate more particularly to
the first portion of my Invention, and are shewn as an example, how the
Invention may be carried into practical effect, I will proceed to describe
their general arrangement, construction, and adaptation for the purpose
of their design before entering upon the description of those views.
relating to the second part of my Invention, as shewn in Sheet 2 of the
Drawings.
In addition to the present pair of rails a, a, a third rail b would be
necessary and this one insulated. It might be iron with an oblong
section, say of one inch by two inches, so small since there would be no
strain whatever upon it. When laid it would stand up as a small girder
two inches deep. This would be supported on chairs c, c, and must be
slightly raised above the ground. The present sleepers c¹ would be the
fixing points for these chairs. The rail would have a small piece of
ebonite d at its sides and below which might be fixed to it, but only in
those places where the chairs form supports. The rail when in position
is "tightened up" with wooden wedges which are driven in one or both
sides of the rail where the "chairs" are, and one, e¹, below which would
raise it up if at any time it were to sink. The pieces of ebonite d on the
rail would be rounded lengthwise, also chamfered away from the rail so
as to secure all wet running off. The rails might be secured one with
the other by means of fish plates. In describing this system ininutely
one arrangement is shewn as an example only for carrying it out, as the
intention is only to demonstrate one method so as to make the general
manner of using this system clear.
The electric line 6 is laid in blocks, every block overlapping the last
one, which is accomplished thus. Where one block ends and the next
begins, instead of simply cutting the rail at this point so as to make it
discontinuous, the rail of the block in front continues, having formed a
crook or bend first, side by side with the line of the last block, although
not in contact with it. Figure 1 shews this clearly, and represents
a few complete blocks. The overlapping portion would be considerably

page_text: longer than the distance required to stop a train going at a very high
- speed. The overlapping piece b continuous with the crook will be
described herein-after as the "front signal line," and the portion of rail
`running next to this as the "back signal line"; since it is supposed the
trains run towards the right hand of the Figure, it is evident these terms
are strictly logical because the "front signal line" is continuous with the
front block, and the other with the block behind. It is also seen that
this rail is always in a straight line, except the crooked portions which
run by the side parallel to the system.
Under each engine are two metal wheels o, o³, see Figures 2 and 3,
borne on one axis which is supported in suitable bearings and pressed
downwards by the springs f. f. These wheels o, o¹, are insulated one
from another by one or other of the numerous methods now in practice,
and the distance between them is the same as the distance between the
"front signal line" 6 and the back signal line b'.
1
Facing the direction in which the train is going, see Figure 3, on
arriving at the termination of one block and commencement of the
next, the wheel o (the left hand one) will roll on the front signal line b,
while the other wheel o¹ (the right hand one) will roll on the "back
signal line 6', but at other places the left hand wheel will be free (see
Fig. 4). To avoid a shock when it suddenly runs on or off the " front
signal line" this latter is wedged off to nothing at its commencement
and rounded at the crooked end. A guard or brush p¹ is placed in front
of the wheels to clear the electric lines of snow or pernicious matter.
The engine carries several pieces of apparatus, but to commence I
will only suppose there is a battery and an electric bell (see Figures 6,
7, and 8).
86
One wire from the battery and one from the electric bell are taken to
earth" by being simply attached to the engine, the current passing
through this to the ordinary railway lines which are connected with the
ground. The other wire of the battery is in connection with the right
hand wheel, and is insulated from the engine. The second wire from
the electric bell, also insulated from the machine is connected with the
left hand wheels. The wheels just referred to are the signal wheels
spoken of above. Now suppose a train to be in a block," then the
right hand wheel o is upon the line, and to this is attached a battery
wire o². One wire from the battery goes to earth, but since the other is.

page_text: now through the signal wheel in connection with the insulated line b
no current can pass unless this rail is "put to earth." Now suppose
another train to enter this block, the electric bell o³ on this engine
commences ringing so long as there is a train in the block it is about to
enter, and the driver must pull up his train until it ceases ringing. The
reason for this is the bell signal wheel o¹ of the second engine is at the
commencement of a block on the "front signal line b, and being con-
'nected with "earth" by the wire o', which passes first to the bell o³,
then to "earth," affords the means of putting the front block line to
"earth," and therefore completes the circuit of the battery on the engine
in front (whose battery signal wheel is on the rail), and also causes the
bell to ring on the train behind. Moreover this train, which has been
signalled to stop, has control over all the block it has just run over,
because its battery signal wheel remains on the line of this block, so if
another train were to enter behind this one its bell would announce a
train in front, and so on all down the line. The overlaps should be of
considerable length, so that control may always be maintained over the
block just passed over, notwithstanding the distance the train has run in
pulling up. From what has been said it is evident every front train has
control over a train behind.
An indicator, such as has been before described, is also employed, one
coil in it being placed in the circuit of the battery signal wheel, and the
other in that of the bell signal one, so that when a current passes the
needle deflects right or left, according to which circuit has a current
passing through it. Upon consideration of what has been detailed the
deflection of the needle is to one side or the other, according as a train
is in the block in front or entering the block behind; but suppose both
these events occur at once, then the needle will attempt to be deflected
both ways at the same time, which is impossible, and therefore will
either remain stationary, or move slightly to one side or the other if the
currents in the coils are not quite equal. It is then very easy to detect
the signal, for ordinarily when the needle is at rest it means "safe," but
when at rest by reason of a train in the block in front and one waiting
to enter the block behind the bell is ringing, so no confusion can arise.
The needle of the indicator on turning to the right or left strikes against
a bell, the right one having a different tone from the left. Of course a
lever on the arbor carrying the needle or other arrangement might easily
effect this end. This indicator might have a dial similar to that shewn

page_text: "
at Figure 6, marked below " signals on the left hand "train behind,"
at the right side "train in front," and at the point where the needle
stands when at rest, "bell ringing train behind and in front." The
magnetic needle would be slightly weighted to keep it vertical, as in an
ordinary "detector." Any unsteadiness in the needle might be over-
come by two small spiral hair springs attached to the needle arbor by
their centre ends, their other ends to fixed points, so as to be opposed to
each other when in action. This indicator is really not wanted for
ordinary signalling, although its presence would be serviceable if from
any cause the current were weak, or the electric bell did not act.
A guard placed before the wheels would remove any material which
may lie upon the line, and also protect the wheels from damage. Other
points worth mentioning are these,-all the wear on the insulated rail
arises from slight downward pressure, and not a portion of the engine's
weight; the wheels moreover are flat, so that this line would last much:
longer than the rails upon which the trains run.
Where crossings for persons and carriages exist it will be found
necessary, as is now commonly done, to raise the level of the ground up
to that of the rails, with a border of stone next to them, or any other
convenient protection could be employed. Where the line is likely to a
be flooded at certain times of the year the old semaphores could be left
at these places, for the plan detailed for signalling will not act under
water, unless considerably modified. Even where floods occasionally
occur the insulated rail might be above or at the side of the train instead
of below, and an apparatus on the engine could be made to run on it.
Again, it might be said generally, a heavy fall of rain would stop all
signalling; this is however a mistake, it does not put an end to
telegraphy, although there is much waste of electricity when the insu-
lators are wet; but in this system the resistance is so small, because of
the short lengths of line and its large transverse sectional area that loss 3
of current will be imperceptible. The underneath and sides of the line
might be dipped in asphalt, which is a non-conductor, and could then
even partly lie in water without affecting the system; but if the roads
are drained as they should be and generally are no trouble on this head
can arise. Again, no sufficient amount of rust will ever form upon the 3
line to have a deleterious effect; the passing of trains being frequent,
together with the pressure of the wheels upon the line, would soon
remove any which might form, and even if a little did the resistance of

page_text: the circuit being so small, the effect would be only slightly to
increase it.
The arrangement and action of the electric bell may be described as
follows: An electro-magnet already described has an aŕmature before
it borne on a spring in such a manner that it is drawn away from the
magnet poles or ends; to this also is fixed a wire carrying a weight to
strike the bell. There is another spring which presses the armature
towards the magnet poles, yet not sufficient to push it against them.
One end of the wire passing round the magnet goes at once to the left-
hand signal wheel, whereas the other is attached to the armature spring,
and the current then traverses the armature to the other spring, thence
to "earth," thus completing the circuit when a train is in front, because
its right-hand signal wheel is on the line which goes to the battery
whose other pole is "put to earth." Hence, the moment a current
passes the electro-magnet becomes magnetized, and the armature is
drawn towards it, at the same time giving the bell a strike with the
hammer attached to it. But the armature now being drawn from
contact with the spring pressing it the current ceases to pass, then
by the spring of the armature it is restored to its former position,
when the same thing is repeated again and again producing a vibratory
ringing.
39
The following is the description of an arrangement of apparatus by
which every signal could be marked on paper. The arbor in the
indicator would have one lever pen or more if desired attached to it,
or some marking instrument, such as is used with the "telegraphic
Morse," or even there might be a small apparatus on the same principle
as the "Morse itself placed in the circuit. A piece of clockwork
would always advance a slip of paper at a certain regular rate, i.e., a
fixed number of inches per hour, so that the time could at once be
ascertained when any signal was given by measuring the distance of the
mark made by the signal from the end of the strip of paper. A con-
venient method would be to have the paper marked atevery quarter of an
inch with a red dot, then the distance from one dot to another represents
a stated interval of time. Danger signals would of course be the only ones
reported, and in addition the apparatus would be so contrived that so
long as the engine is stopping a line is being drawn upon the paper.
The "
signal marks" and the "stopping" line on the paper would be.
side by side. Likewise, during the time "danger" is set, i.e., the bell

page_text: is ringing on the engine, the pen is marking on the paper, consequently
a line will be formed here also. These lines could be black to contrast
with the red "time dots."
The clockwork can be made to shew at what time the train was
started from its first station, then we have a test as to whether it left
punctually. To show the use of this arrangement in practice, when the
train arrives at its destination the station master will unlock the box
on the engine in which the mechanism is situated and tear off the piece
of paper which has passed through during the journey. He can then
ascertain the following facts,-
First. If the train started at the proper time.
Second. How many times danger signals were given en route.
Third. If these were obeyed for in every case the length of the
"danger line" on the paper should equal the "stopping line," which
indicates the engine waited whilst the danger signal lasted.
Fourth. How long a train stopped at any station, because here a
stopping line only will be seen.
Fifth. Whether any time was lost on the road, and where; also the
precise time of day.
Sixth. When any irregularity occurs, with whom the fault lies.
By keeping this portion of the apparatus under lock and key no one
can tamper with it, and the proper authorities can depend on the
register kept being a correct one.
The mode of producing the "stopping line" is simply to shut off the
steam. The lever for accomplishing this will cause a pen to mark the
moving paper when the former is in a position for the steam to be
turned off. The clockwork just spoken of might be made self-acting
either by allowing the engine while going to keeping it wound up, or
what would be better still by having a miniature "donkey engine” on
the locomotive to work the wheelwork instead of a spring,) which should
always be kept in motion whether the engine were stationary or running.
I believe this would also be the cheapest plan. A separate stop-cock
would admit the steam to its cylinder; this would only be shut off when
the engine was not in commission, and if touched at improper times the
paper" would at once indicate it by shewing an impossibly short
"time" revealed by the other signals marked on the paper. Or the
"

page_text: "
proper authorities at the termini might turn the " donkey engine on
before the train left with a private key. If the paper passes at the
rate of six inches per hour it would be amply sufficient for the purpose.
It would be highly desirable that the guard's van at the end of the
train should also have a pair of signal wheels, battery indicator, and bell,
and communication could be then effected between the guard and the
driver by means of a small "lever key," whereby the signal wheels of the
former could be practically changed in position by cross connecting
the wires from them. This "lever key" or "commutator
" has a spring
so that it can only be made to act when the hand is kept upon it. It
has all along been assumed that it is necessary for the signal wheels o, o,
to be in contact with the line. This is not absolutely necessary, although
perhaps the preferable method. Peculiarly constructed coils of wire
might take the place of these wheels, and simply hang over the insulated
rail instead of touching it. A current must then be flowing continually
in that coil,, which takes the place of the signal wheel in connection
with the battery. In cach coil one end of the wire goes to carth. Here
the phenomena of induced currents are called into play, one current pro-
ducing another in a conductor placed near it, also conversely, a conductor
with a current passing in it will induce one in a coil approached to it.
When this system is employed the coils must be placed at a small dis-
tance one behind the other in different planes, also further apart laterally,
because the "front and back signal lines" must also have a greater
distance between them in order in no case to produce cross currents or
5 currents in parts of the system where they should not be.
There are
many ways of bringing about a visible effect by electricity without
contact between the electrified body and the instrument to be affected.
Here only one method has been pointed out.
The second portion of this Invention, relating to the automatic action
of the shut-off valve and application of the breaks, will be more readily
understood on reference to Figures 10, 11, and 12, Sheet 2. Figure 10
represents an arrangement of electrical apparatus for shutting off the
steam or opening the whistle of the engine; and Figure 11 and 12
represent respectively in front elevation and plan views an arrangement
3 of apparatus for applying pneumatic or other breaks through electric
agency. In Figure 12 m is a pipe communicating with a whistle or
donkey engine, which may be employed when communication through
the same is opened from the locomotive boiler for exciting electricity by
-

page_text: magnetic-electric action through the medium of suitable mechanism for
working the system herein described in lieu of batteries; or such engine
may be employed for applying break steam power automatically as
follows: This pipe m is provided with a cock n, the plug or valve of
which is provided with a lever, and which when the cock n is closed is
retained in a vertical position by means of the projection on the
armature p taking into the recess or notch formed in the top of such
lever o.
Above the armature the magnet q is fixed, around which the
wire on its way to the electric bell before mentioned coils. Thus when
"danger" is set and the bell is ringing the electric-magnet q attracts the
armature p, and so releases the lever o, which being acted upon by the
spring o' is thrown back, so as to open the thoroughfare forming com-
munication between the boiler and shut-off valve and whistle, or with
the donkey engine before mentioned, by which the steam can be shut off
and the breaks powerfully applied; or if desired the train can be supplied
with pneumatic breaks, which when ready for use are kept free of the
wheels by means of the ratchet wheel and catch r³ (see Figures 11 and
12). This catch r¹ forms one end of the lever armatures, which is supported
and works on the fulcrum 8¹ in a position which will allow it to be acted
upon by the electric magnet t. This magnet is likewise acted upon in
manner similar to that described in Figure 10, and when so acted upon
the armature s is attracted so as to relieve the catch from the ratchet
wheel r, thereby allowing the pressure of air or other powerful mechanical
action to come into play and apply the breaks. It will thus be seen
when one train approaches within the prescribed limits of another one,
assuming them both to be fitted with the most complete apparatus, the
train behind is stopped, the bell on the engine rings, and the indicator
shews "train in front," also having given a ring on its bell, likewise these
facts are recorded on paper. The bell in the guard's van also rings, and
his indicator likewise shews the cause. But in the apparatus on the
engine attached to the train in front and in the brake van behind nothing
occurs but one slight ring of the indicator bell by means of its needle,
which shews "train behind." The electric bell on the engine does not
ring, nor is the train stopped.

page_text: can ring the bell on the engine, and hence he can stop the train. The
same may be said of the passengers if there be communication through
the whole train from the engine with proper handles placed in each
compartment, certain penalties being attached to persons misusing
them.
At "crossings" (i. e., level ones) the front and back signal lines are
to be laid side by side for a considerable distance from the crossing, and
there so connected together that if one train is near such crossing every
other train and itself if another should come will be stopped on
approaching this part. A rule of the road might then direct which set
of trains shall advance first, so that they may not have to wait inde-
finitely. But what is far more desirable is that there should be a signal
box at these places, with as many single indicators (i. e., indicators with
only one coil) as there are sets of lines crossing (and the signal rails on
which the battery signal wheels run of each set of lines would be con-
nected with one of these indicators), also a local battery connected with
the insulated lines on which the indicator signal wheels of the engines
run; then all trains coming to within a certain distance of the crossing
will be stopped, and the indicators in the box will show on which sets
of lines the trains are. The signalman can signal to all trains on
one set of lines "safe (by breaking the circuit), so that these will
advance. When his indicator comes to rest for those lines, then if trains
are waiting on other lines crossing these he signals the same to them,
and so on; or he may make any set "
open " in the first instance by not
permitting the local battery to have any influence over that set of rails.
By a
"set of rails" is here to be understood all those laid parallel.
Other plans could be devised if found more desirable.
"
We come next to sidings (not with facing points) and facing points.
Although the latter are the more dangerous I shall treat them on a par.
In these cases there will be a local battery in connection with the insu-
lated line of the siding or loop line. Now when the "switch" is set to
let a train into the siding the arrangement is such that the insulated line.
of the loop is in electrical contact with the signal line of the main line,
so that a train approaching would be signalled to and stopped by the
local battery. Hence whenever the loop line is open approaching trains
will be pulled up. But supposing this loop were opened intentionally
to permit a train to pass into it, then by the use of a second lever the
local battery could be thrown out of circuit, and the train would run up

page_text: and into the loop, for in this case no danger signal would have been
given. A double lever would be more convenient than two levers. One
form of double lever is shewn at Figure 13. Henco if the siding were
left open by accident there is no fear of a train running into it, because
danger" is set.
"
On locomotives instead of batteries electric-magnetic machines might
be employed, and the same "donkey engine" before spoken of to work
the registering apparatus could employed to work this electric current
producer also. The electro-magnetic instrument consists in its simplest
form of an electro-magnet rapidly revolving before a permanent one,
poles opposed to poles.
There are many forms of electro-magnetic machines in use, but they
are chiefly modifications of the one described, or induction is produced in
some other convenient manner. The current produced by this method
being alternately reversed, a self-acting "commutator" is employed to
cause the current to flow always in one direction, as is the case with a
battery. In this system the ends of the wire of the electro-magnet
would be treated just the same as the wires of the battery, had one been
There are certain places on the line whence it would be desirable to
communicate with a train in motion, especially near stations. If a signal
line is laid so that the signal wheel of an engine which is connected with
its indicator runs upon it, and this line extends to a certain distance
from the station and is connected by a wire at this latter place with a
"lever key" placed in the station master's room, then he can telegraph
to the train when it nears his station; because if his "key" goes to
battery and one wire of the latter to "earth," then it is plain that on
depressing his key (thus placing his battery in contact with the signal
line) a coming train will receive the signal. But how will the driver
distinguish this signal from that of "danger ?" So long as the key is
kept down so long will the bell of the engine be kept ringing and the
train detained; hence the station master can stop a train before it enters
his station if necessary. Then he intends his signal to be " danger."
Suppose he does not desire to stop the train, but only to some messuage?
He will then work his "key" up and down the necessary number
of times for imparting his communication. This key is kept from
→

page_text: producing continued contact by a spring pressing its lever upwards, which
makes it also more easy to work, every depression sending a current.
"
On the engine of the approaching train the bell will give one stroke
for every successive rapid depression of the " ‘key,” the needle of the
indicator likewise following the movements of the key. No " danger
signal would do this, but the bell would keep on ringing and the needle
having turned to one side would remain there so long as this signal
lasted. The train moreover is not stopped, since although the steam is shut
off at each ring yet it is not for a time sufficient to have effect on the
train. Thus the driver would know the message sent by the number of
rings on his electric bell. Moreover in order that the station master may
know when a train is within communication distance the ordinary signal
line may be connected with a "a single indicator" in his office. Or the
communication from a station to a train in motion may be effected
by simple placing at some desired distance upon the line a lever
armature, shown in Figure 9, Sheet 1, which is actuated by the magnet u
in connection by means of an insulated wire with a battery at the
station, the opposite pole of which goes to earth, thus when the electric
magnet u is magnetized the armature v forms contact with the signal
rail b, and so forms circuit with a passing train through the medium of
the bell signal wheel o, the continued action of which stops the train and
the intermittent action sends messuages only.
In case of accidents the guards of all trains would have with them a
portable battery and an "earth key." When an accident happens, such
as a landslip, tunnel falling in, or train running off the line, or a mishap
whereby the train is thrown from the metals, the guard would attach
one wire of his battery to the signal line and clip the other to an ordinary
rail, that is to "earth," thus he could signal danger to all coming trains.
The "carth key" is an ordinary "lever key," with its wires connected
in the same way when in use as the battery wires just mentioned, and in
certain situations along the line where a block commences it might be
found useful to signal to trains in front after the same fashion as a
station master would signal. Speaking generally, at any point a man
carrying these two instruments could signal to any train to stop, sup-
posing it were so required.. These instruments also give us a method of
testing whether the blocks are in good order, two men being employed
to walk down the line, block distance from cach other, and one applying
his key, the other his battery at the commencement of each successive
B

page_text: block, permitting the current to pass through a "single indicator." This
latter instrument is generally called a "galvanometer," and in a certain
form a
"detector." The guards might also carry this latter instrument
with them.
I suggest a method by which every train along a line could be stopped t
at once, or it might be used as means of ascertaining at any moment if
all the blocks forming a line were in good working order. After
describing briefly this method, those who are familiar with the modes of
testing employed in telegraphy, will perceive how a fault could be
detected at a certain spot without examining the whole line. It is not 1
proposed to detail the method very fully, a general description is
sufficient, any one who has studied the subject will understand it
thoroughly from the following short survey, and to others the matter
will be tollerably clear after a little consideration.
The polarised relay will now be described, and then the instruments 1
to be employed for testing the blocks will be understood. The poles of
an electro-magnet are caused to be each a north pole or a south pole;
here, for instance, suppose north. This is done by placing at the farther
end of each leg the north pole of a permanent magnet, thereby inducing
a south pole in the contiguous part (i. e. of the electro-magnet) and a 2
north pole at its other extremity. Now suppose the south pole of a
balanced permanent magnet to lie between these north poles, then it will
be equally attracted to each, and therefore rest centrally between them:
When the electro-magnet is magnetised by a passing current it thereby
makes a north and a south pole of its own. The effect is to weaken one 2
of its induced north poles and strengthen the other one, so that the free
magnet will now be attracted towards the stronger side, and consequently
move towards it. If this current be reversed the free magnet will move
in the opposite direction.
Suppose where every block commences and the next one ends all 3
along the route there is such an instrument placed; moreover, imagine
always that wherever a battery is used it is invariably the same pole
(i. e. zinc or carbon wires), which is put to earth, say for example the
zinc pole; then the magnetic needle of each relay will always be moved
towards the same side provided one end of its electro-magnet wire goes 3
to a block signal line and the other to "earth;" then no effect whatever
shall be produced on the general system. But if at one extremity of

page_text: the line a "carbon pole" is put to earth and a zinc pole to line, then
the needles of all the relays will move in the opposite direction (in
succession) by a proper arrangement introduced into these instruments,
whereby the wires going to earth will be in connection with the next
block, and then all the separate blocks are connected into one line, so
that if they are perfect the current will pass from end to end, and may
be made to shew itself by means of a "detector." It is also evident
that all trains on the line of route could be stopped by this process.
Local batteries could be employed where the relays are situated if
desired. Thus, instead of sending a current from one end to the other,
a current may be sent through one block, which causes another current
to pass through the next, and so on; but under ordinary circumstances
this uniting of blocks would not occur.

page_text: The "chairs" might be cast in glazed earthenware, in lieu of those
previously described, if practice should show them to be more desirable.
The signal rail need not necessarily be placed between the rails and
under the train, at the side of the rails considerably above the ground,
or overhead, would answer the purpose equally well. The system might
even be laid partly above, partly below, and partly at the side of the
trains, but then a slight modification would be necessary in the character
and disposition of signal wheels.
The signal wheel should be broader than the rail on which it runs
to ensure contact, even should the wheel or rail accidently shift
slightly.
.
The whole of the additional apparatus (except the signal wheels)
might be fitted in a box, which would only require fixing to the engine,
when the "unions "would be screwed up, and the wires attached to
their continuations. The signal wheels might be manufactured complete
in a frame, then this would only require fixing in front of the engine on
the plate to which the "buffers are attached. Hence the time occupied
in altering a locomotive for the new system would be very short.
"
It has so far been supposed that there have been two signal wheels on
the engine, and two on the guard's van. Now when a current from a
train in front affects an engine's indicator the electricity passes to earth,
then how can this current affect the guard's indicator? The answer is
plain enough, if there were none the question would appear to take
away one of the great advantages of the system. The resistance of the
signal line between the engine's signal wheels and those of the guard's
van may be almost disregarded, but it may however be allowed for by
slightly diminishing the resistance of the instruments in the van either
by increasing the thickness of the wire in the apparatus or by employing.
a: better conducting wire, or by shortening its length.
Now when a current from the battery on an engine (after passing
through the signal line) meets the signal wheel of a locomotive on a
train behind it finds two courses to earth, one through the indicator on
the engine, and the other through the indicator in the van, but since the
resistance in each of these courses is nearly equal the current will
""split," and pass half by each road to earth, thus affecting both
indicators.

page_text: It is by no means necessary that the signal wheels should be always
used in pairs, for if the engine only had the signal wheel which is in
connection with the indicator and the guard's van, the one which is
connected with the battery, it is obvious that the signalling would be as
perfect as when the signal wheels were employed in pairs.
'
The objects for having two signal wheels are as follows:-
First. To secure perfect signalling, even when an-engine has no train
attached to it, and consequently no guard's van.
Second. To secure double safety.
When a train is drawn by more than one locomotive, or has many
guards' vans, the various apparatus on all these will act harmoniously
and coincidently together.
Suppose one of the signal wheels were to break the result would not:
be to impair the signalling, because both the engine and guard's van are
fitted with such wheels. As an extra precaution however each engine
might carry a spare wheel,
There are often peculiarities at certain places along a line which
would require a slight modification of the system described, not because
it is actually necessary, but because it might be found more convenient.
The best and most practical method of testing the signal line would
be to allow two engines to run over the whole length of the line within
block distance of each other.
There are many ways by which the signal line could be protected
where there are level crossings for horses and carriages. One method
only has been spoken of hitherto. Another would be to conduct the
signal line (in the shape of an insulated wire) underground at these
places, which generally do not exceed a few yards in extent, or to have
the frame of the signal wheels hinged in such a manner as to permit of
their always rolling on the signal rail, even if this were laid at different
levels (see Figure 5, Sheet 1). The difference between the highest and
lowest level of the rail could not much exceed twelve inches; thus the
rail at traffic crossings might be laid lower than along the general line of
route, and at such places might be protected in a trough. At present a
train is signalled before it reaches a station; in the new method of sig-
nalling this would also be done. The fact that the train had come within.

page_text: communication distance of a station would cause an electric bell, placed
in the circuit there, to ring. The signal wheels might have their cir-
cumferences grooved instead of flat, if found preferable.
The following would be a cheap and efficient mode of insulating and
fixing the signal rail :-Wherever a chair supports the signal rail let
this latter be surrounded on three sides by a piece of sheet machine
india-rubber; then a wooden wedge would fix the rail firmly in its
place. The upper surface of this rail would of course be the side not
covered by the india-rubber.
The conductor joining a signal wheel with its instruments could not
be an insulated wire attached directly to it, but there is no reason why
it should not be attached to the part which supports the axis of these
wheels, when the current will first flow through the axis then through
its bearings to the wire. Or one of the many means now in use may be
employed for securing good electrical contact between a revolving wheel
and a stationary instrument. Neither the signal wheels nor the axels
would ever become hot enough to injure their conductivity, because the
diameter of these wheels would be of a fair size and the axels kept cool
with grease.
+
• When polarised relays are employed as a means of inviting all the
blocks of a line into one continuous signal line, since one end of the
wire on its electro-magnet goes to a block signal line and the other to
earth, it might be supposed this would destroy the signalling. However,
if the resistance of the wire on the magnet be made sufficiently good
not to be overcome by the batteries generally employed this apparent
trouble will vanish. When it is desired to make the relays act a
battery power great enough to overcome the resistance of one relay
together with the resistance of the whole length of signal line would be
necessary.
After a current has been sent through the whole of the blocks for the
purpose of testing the signal line in the manner before described, it will
then become necessary to make the blocks again separate. Now
reversing the current at one end of the line will not bring this' about
because after the current has restored the relay of the block nearest
whence the current was sent to its normal condition, the electricity will
pass through this relay to earth, and consequently the current will not

page_text: disunite the remainder of the blocks. However, trains running on
the line would cause successively all the blocks to become separate.
Thus
The better method to adopt would be to have a spring in each relay
which should keep the magnetic needle in its normal position.
when a line is being tested the springs of all the relays along this line
will be in a state of tention, and when the testing is completed these
springs in distending would again make all the blocks electrically
separate.

page_text: The following are a few of the modifications on which
system might be worked.
Unis new
First. By having a local battery in connection with each block and
no batteries on the engines or guard's van.
Second. By employing the local batteries, and likewise batteries on
the locomotives and vans.
Third. By dispensing with the signal rail; then a wire would take its
place, which might be stretched on posts by the side of the line, which
is preferable in countries where snow accumulates upon the track. Also
a piece of mechanism would be placed at the commencement of each.
block, which would be set (mechanically) by a train entering a block,
and unset by a current sent through the wire when the train leaves the
block. It is evident that the part of this mechanism which would
act as the signalling portion, viz., ringing a bell on the engine
mechanically, must be placed at a considerable distance from that
portion of the apparatus which would set the nearest signalling apparatus
and unset (at the same time) the next signalling instrument which is
behind it (i. e. speaking relatively to direction). Hence the mechanism
at the beginning of each block would consist of two parts, viz., the
signalling instrument and setting apparatus.
The signalling for "crossings" and "facing. points" would be the
same under this modification of the system as under the one previously
detailed in full. The engines could also be stopped automatically. A
short piece of signal rail would be laid from the "signalling instrument"
to the "setting apparatus,” by means of which the driver would know
when the line is clear. The train might then be made to advance of
its own accord. In fact everything which could be accomplished by the
system as herein explained might be done under this modified method..
Here we have mechanical arrangements combined with electricity.
The above modifications of the system, to which others might be
added, are only very briefly described, since their full developement
could be perceived with a little thought.
Last, but not least, the engine driver, guard, and other officials in.
authority would be able to test the electric apparatus either daily, as a
matter of routine, or when suspected; this could be easily done by
placing the instruments used on the engine on short circuit, i. e., allowing.

page_text: the current from the battery on the locomotive to pass through its own
indicator, which is accomplished by means of a "commutator" used
only for this purpose. The instruments in the guard's van, and all the
apparatus employed in the new system would be tested in a similar
manner.
When the instruments are placed on short circuit the current should
be permitted to pass through a resistance coil having a resistance which,
if overcome by the current, should show that the battery power is
sufficient for signalling purposes.
The commutator used for testing would have a spring, in order that
it should always be out of use, except when the hand was upon it for
the purpose of testing.
It is not necessary further to claborate the system herein specified as
it will readily be understood by those versant with electric apparatus
and their manifold arrangements that many forms of signalling could
be adopted through the medium of the electric system herein described
therefore.
Having now described the nature of my said Invention, together with
one arrangement which I have shewn as an example for carrying the
same into practical effect, I wish it to be distinctly understood in con-
clusion that I do not wish to confine myself to the actual detail and
precise configuration of the parts shewn, as the same may be modified
and still retain the essential features of the Invention, therefore it is
my desire to claim,-
First. The general arrangement and construction of the parts described
in the Specification and shewn in the Drawing as the line of electric
rails marked b, b', and signalling wheels marked o, o¹, together with
any slight modification of the same, and their application to the per-
manent way and rolling stock of railway to be used in connection with
batteries and electrical apparatus in the manner and for the purpose
as herein-before described and set forth.
And, Secondly. I claim the novel and peculiar arrangement and
adaptation to railway trains and engines of the electrical apparatus
herein-before described for producing automatically the action of the
"shut off" whistle and breaks of the engines to be employed for the

page_text: purpose, as herein-before substantially described and set forth in the
Drawings annexed.
In witness whereof, I, the said David Lionel Salomons, have here-
unto set my hand and seal, this Twenty-third day of December, in
the year of our Lord One thousand eight hundred and seventy-
four.
Witness,
GEORGE CHITRIERS,
Butler,
Broom Hill.
DAVID L. SALOMONS. (L.S.)