IMPROVE- MENTS IN THE MODE OF WORKING TELEGRAPHIC LINES AND IN INSTRUMENTS PROVISIONAL SPECIFICATION
Year: 1862

page_text: LETTERS PATENT to William Hickling Burnett, of Margaret Street,
in the County of Middlesex, Gentleman, for the Invention of "IMPROVE-
MENTS IN THE MODE OF WORKING TELEGRAPHIC LINES AND IN INSTRUMENTS
PROVISIONAL SPECIFICATION left by the said William Hickling
Burnett at the Office of the Commissioners of Patents, with his
Petition, on the 18th November 1862.
I, WILLIAM HICKLING BURNETT, of Margaret Street, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MODE OF WORKING TELEGRAPHIC LINES AND IN IN-
STRUMENTS AND APPARATUS EMPLOYED FOR TELEGRAPHIC PURPOSES," to be as
follows:-
Firstly, my improvements in the mode of working telegraphic lines consist
of various arrangements by which increased rapidity is produced in signalling
by means of electricity, especially where subterranean and submarine lines are
used, and by some of which the obstructions now caused by accidental currents
are either wholly or partially removed.
Secondly, in improvements in certain instruments and apparatus used in
working telegraphic lines.
My first improvement has for its object to diminish or remove the evil
effects of earth and other accidental currents; I do this by having a second line
A

page_text: parallel to the working line.
Both lines when signalling is not taking place
are to earth at both ends through coils wound in opposite directions round the
instruments, so that whenever earth or other accidental currents set in as the
two lines are exposed to the same influences these currents balance each other,
and when a signal has to be made, a current from a battery is sent through
one of these lines and acts on the instrument without any disturbance or
interference from accidental currents. By coiling the two lines in opposite
directions round instruments arranged on the plan of those I hereafter
describe when explaining my mode of working two distinct systems of telegraph
through one line wire simultaneously, I make each of the two lines a working
line at the same time, the instruments of both being quite independent of
accidental currents and of each other.
My next improvements in the mode of working telegraphic lines are in-
tended to diminish or obviate the loss of time in transmitting signals which
occurs with the present plans of so doing, especially when the wires are sub-
terranean or submarine. I effect these objects in various ways. In some of
them two wires at least are required, and I cause the signalling line to be
wholly or partially charged from both ends every time a current is sent, and
when it ceases to be immediately discharged at both ends to earth. In others
which also require two lines at least one or both of the lines is kept constantly
charged. Other modes require but one line and generally with a battery at
each terminal and the line is also always more or less charged.
One of the arrangements I employ in carrying out the first named plan
is to have a battery at each terminal, the dissimilar poles of which are per-
manently joined by a wire at the receiving station; the pole of the battery not
connected with this wire goes permanently to earth, and is also attached through
a receiving instrument to another wire which is the signalling line. This wire,
which also has an instrument connected to its other extremity, is normally to
earth at the sending end, but when a signal has to be made this connexion is
broken and it is put to the free pole of the battery at this terminal, when the
current enters at both ends and makes the signal, after which the line is again
put to earth and discharged. Or, retaining the same arrangement at the
receiving station, both wires may be permanently fixed to opposite poles at each
terminal, and both batteries be normally to earth by one pole. In this state
of things no current will be flowing through the signalling line but constantly
through the other, but if connexion with earth is broken at either end the
current will flow into the signalling line at both ends and will continue to do
so until the pole is again placed to earth, when the signalling line will discharge
at both ends. Or connecting like poles by the non-signalling wire, but

page_text: retaining a similar arrangement at both ends, excepting as regards any con-
nexion of the battery with earth at the sending end, signals may be made by
reversing the direction of the current, or by dispensing with a battery at the
sending end and keeping the signalling line normally to earth and the other
line insulated by putting the two lines momentarily in connexion.
go to
An arrangement I use in carrying out the second system named is to con-
nect the two lines at the receiving end whilst at the sending end they
the opposite poles of a battery, at the receiving end a wire goes to earth
permanently round the instrument from the junction of the two lines. The
current is thus constantly flowing round the two lines and signals are made by
putting either pole of the battery to earth through an instrument, at the same
time breaking or not breaking the line connexion with that pole. In carrying
out these systems in most cases I prefer to use a battery at each end of the
line, although, as I have shewn, it is not absolutely necessary, and I sometimes
use a third line instead of earth. The different methods I have explained
effect perfectly the objects intended, but the connexions of the wires with the
poles of the batteries, earth, and each other may be considerably varied and
yet produce the same results. I do not therefore confine myself to these
particular arrangements. The following are some of the various plans
I adopt when using only one wire, they all require a battery or batteries
at both terminals of the line. In the first arrangement the battery at the
sending end is of considerably more power than that at the receiving end, and
normally similar poles are united by the line through instruments at each end,.
the other poles going to earth. In this state of things an opposite prepon-
derating current will be flowing through the receiving battery, but on reversing
at the sending end a current will flow into the line from the receiving battery
and make a signal, or, keeping the same arrangements, I sometimes introduce
an earth connexion through a powerful resistance coil in the middle or other
part of the line, and make the signal as before stated. Or I sometimes keep
the line normally to similar poles of equal batteries, and make the signal by
doubling or increasing the battery power at the sending end. Or I connect
the line through the instruments with similar poles of equal batteries, the
other poles of which are to earth, but at the receiving station between the
instruments and the battery I have an earth connexion through a powerful
resistance coil and signalize by reversals, or I have an earth contact through
powerful resistance coils between the instrument and battery at both ends of
the line, and signalize by reversals. Or at the receiving end I have a battery
from. the centre of which is an earth connexion. The two poles are joined by
a wire on which are one or two powerful resistance coils. To the-centre of this

page_text: wire is attached one end of the line through an instrument; the other end of
the line is fastened through an instrument to one pole of a battery, the other
end of which is to earth; signals are made by reversals with this battery. I
sometimes signalize with the aid of the synchronously moving wheels described
in the Specification of my Patent of May 23rd, 1860, No. 1271, by causing
the line to be put automatically to the battery and earth or to different poles
of the battery alternately, or otherwise at the receiving end or at both ends,
simultaneously, signals being made by reversing or making and breaking by
means of the key at the sending end. Sometimes I use batteries of equal
force at the terminals and sometimes batteries of unequal force in order to
vary the amount of retardation. In working long land lines, in order to
diminish the retardation of signals caused by the variable state and the ten-
dency to leakage which increases with the intensity of the current, I prefer
sending the message step by step at short intervals from fresh batteries, but
in doing so in the ordinary mode of working a tendency exists for the signals
to become changed in their proportions as they are sent forward with fresh
batteries. By the improved modes of working next described this evil is
removed, and signals may be carried on step by step any number of times
without any change in them taking place. I effect this in one of two ways,
either by so arranging the contacts at each alternate station, that at one
station the fresh current is sent on when the armature is called up, and at the
next when it is released, and so on alternately, or by using small local electro-
magnets to prolong the currents on the system I shall hereafter describe when
speaking of an improved mode of working two or three systems of telegraph
through one wire, and to diminish the irregularities that might arise from
imperfect contacts, I usually keep one end of the fresh step battery to earth
and the other end permanently to line, but a short circuit can be made at each
station, and when that is the case the current will not flow through the line.
At each alternate station this short circuit is made or broken each time that a
signal is sent, and I also frequently employ this sort of contact in other relay
instruments as well as to sending keys to lessen the injurious effects of sparks
at the contacts.
My next improvements have for their object the simultaneously working of
two or even three distinct systems of telegraph through one line wire in such
manner that the instruments shall be made to act in part from one and in
part from the other end of the line or all the instruments at one end from the
other end, whilst, if required, the messages sent from either or both ends are
also being delivered at any intermediate station or stations, or that whilst one
.or more powers of the line are being employed between the terminals the

page_text: other power or powers of the line are transmitting messages between inter-
mediate stations or between intermediate stations and the terminals. To
produce these effects I use currents of unequal force or of different qualities to
deliver the different messages, and I sometimes make all the currents flow in
one direction and sometimes a part in one and a part in the opposite direction,
and the intended signals are caused by the contacts made or broken as
different armatures are moved by the varying currents. To work two systems
on this plan I require to be able to send along the line three varieties of
current, one of which is made to set in action the first instrument, another the
second, and a third both instruments, and to work three systems I require
to use seven varieties of current, one, two, and three varieties set in action
separately instruments one, two, and three, a fourth variety sets in action
instruments one and two together, a fifth variety sets in action instruments
two and three together, a sixth variety sets in action instruments one and
three together, and a seventh variety sets all three in action together. The
description just given is only applicable to those instruments which are worked
with line currents always flowing in one direction, but it is sometimes con-
venient to use one or both powers of the line to work instruments in which
the current flows in alternating directions. To work one power of the line with
alternating currents and the other with currents all in one direction I use five
varieties of current. The first works the two direction instrument alone one
way, the second the other way, the third works the second instrument alone,
the fourth works the first instrument one way at the same time as the second
instrument, and the fifth works the first instrument the other way at the same
time as the second instrument. Of course a double key will be required to
work the alternating current instrument, and I make proper arrangements of
contacts in putting down these keys so as to send currents of the required
force and quality, and I sometimes use the line current direct to work the
alternating instrument, and the relay to work the one direction instrument, or
I work both by the relay or both by the line current. To work both instru-
ments with alternating currents I require eight varieties of electric force,
and I sometimes work one of the instruments directly by the line currents,
and the other by means of a relay local battery, or both by means of the relay
battery, a double key being required to work each instrument sending,
according to the combination of their motions, the required line currents.
compose the relays of electro-magnets and armatures, varying in number
according to circumstances, which armatures are sometimes made of soft
iron and sometimes are permanent magnets, or the relays are partly or wholly
composed of galvanometers.
I

page_text: The above written is a general description of the systems I employ, but
certain obstacles exist in practice to their proper working, and constant
errors will occur without means are adopted to prevent them, which means
form a most important part of my Invention. In those cases where cur-
rents flowing all in one direction are used, when a signal has been made
with one instrument, and then it is wished to maintain that signal, and at.
the same time to make a signal with the other instrument, a different
armature is brought into action, and unless some sustaining power on the
signal were interposed a break would take place during the change in the
first signal. Likewise, when using currents flowing in opposite directions, a
certain interval of time is consumed whilst demagnetizing the instruments.
in one direction, and remagnetizing them in the other direction, during
which the signal would be broken, without this compensating apparatus; this
compensating apparatus is the same to which I have referred when speaking of
maintaining the proper duration of the signals sent, and consists of a small local
relay, electro-magnet or magnets, which require to be demagnetized and mag-
netized before a signal can be made or broken, so that the state of the signal is.
maintained as long as the time occupied by the break caused by the change.
in the line current..
Another source of error is the persistent magnetism which attaches to
electro-magnets when a weak current is sent after a strong one, which renders.
it extremely difficult so to adjust the force of the recal springs that the.
armatures shall fall back when they ought; I rectify this defect by means of
small local batteries, which are caused to send currents kept of any required
degree of force by rheostats round coils in opposite directions to the line
currents, either permanently or only when the line current is sent, so as to
modify the forces of the line currents, or I use galvanometer relays, which are
not equally subject to persistent magnetism effects, especially when arranged as
the relays I shall afterwards describe.
If it is not required for the home instrument to shew the signal sent by
means of the keys, I cause balancing local currents to go round separate
coils in the iustrument, whereby the effect of the home line current sent is
neutralized and the distant current alone indicates, but if it be desired that
both the home and distant signal should indicate by means of the rheostat,
I send a local current at the same time as the line current, of a force only
equal to the difference of the same current. at the two ends of the line.
When I require either or all of the messages sent to be delivered at any.
intermediate station or stations also, I place relays at those stations con-
structed upon the same principles as those at the terminals, but if I require

page_text: any message to go no further than a certain intermediate station, but the other
message or messages to travel further, I send all the currents to earth at that
station, and by means of a repeating relay, send on the travelling currents
from a fresh battery, and also by having a proper manipulating key or keys. at
that station, send on, if required, a fresh message or messages, in lieu of those
stopped.
To enable me to send two messages to instruments worked by the current
only in one direction through one line, I arrange the manipulating keys as
to their contact, so that when one of them is depressed alone, one variety of
current is sent, when the other is depressed alone, another variety is sent, and
when both are depressed together, a third variety is sent. When I intend to
work one instrument by alternating currents, and the other by currents always
in one direction, I require three keys, each of which when depressed separately
sends a particular current, and when the single direction instrument key is
depressed with either of the others, two other distinct currents are sent. When,
both instruments are worked with alternating currents, eight varieties require
to be sent according to the combined action of the keys.
To enable me to send three messages through one line, I make similar arrange-
ments for the manipulating keys, suited to their various possible combinations.
My next improvements are in relay instruments, and have for their object
the power of working with extremely minute and weak currents. The improve-
ments are various, and are not only in electro-magnet relays, but also in
galvanometer relays.
In one variety of the electro-magnet relay, I have no recal springs, but the
movable armatures, which are made very light, and, which may either be of
soft iron, or permanent magnets, are recalled at the proper time by weak local
currents, adjusted by rheostat or otherwise, and these local currents are made
to come into action either immediately at the cessation of the line current, or
by means of the wheels described in the Specification of my Patent of May.
23rd, 1860, No. 1271, after any required interval.
In another variety I use a spring and a local current to overcome it, and
the force of that current may be made to balance the spring, or slightly to
overcome it, so that the weakest line current shall make the spring predominate,>
and so form a signal:
Sometimes instead of a local current: I use a permanent magnet, to the poles.
of which pieces of iron are attached, which form the cores of the line coils, and'
the line current is made to decrease the magnetism of those cores, and thus
cause the spring to make a signal.
My improvements in galvanometer relays and instruments have also the

page_text: advantage of requiring much less wire in the coils than is usually employed.
The magnetic needle is either suspended horizontally or vertically. In the
former case the poles are bent downwards at right angles, and are made to
enter the axes of coils of wire, through which the line current passes, and the
action on the poles is axial. In the second case the needle is somewhat in the
form of the letter Z, and the poles enter into the axis of coils. Instead of or
in conjunction with a slightly preponderating weight, I use a soft iron pin,
acting on one of the poles or on another permanent magnet fixed on the same
shaft, by adjusting which as to distance I increase or decrease the power of the
recal.
My last improvement consists in using a compound receiving instrument, in
which the clockwork and many other parts are single, the marking electro-
magnets and their accessories alone being multiple as the number of messages
capable of being received, the markers being so placed as to act on the same
or distinct strips of paper.
Although I have only spoken of voltaic batteries in describing my improved
modes of working telegraphic lines, I of course wish to imply also any other
source of electricity which may be applicable, and although generally I only
speak of relay instruments, I mean also the telegraphs themselves when no
relay batteries are used.
SPECIFICATION filed in pursuance of the conditions of the Letters
Patent, and of an Order of the Lord Chancellor, by the said William
Hickling Burnett, in the Great Seal Patent Office on the 18th June
1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HICKLING BURNETT, of Margaret Street, in the County of Middlesex, Gentle-
man, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of November, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said William Hickling Burnett, Her special licence that I, the said
William Hickling Burnett, my executors, administrators, and assigns, or
such others as I, the said William Hickling Burnett, my executors, admi-
nistrators, and assigns, should at any time agree with, and no others, from
time to time and at all times thereafter during the term therein expressed,

page_text: should and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for "IMPROVEMENTS IN THE MODE OF WORKING TELEGRAPHIC
LINES, AND IN INSTRUMENTS AND APPARATUS EMPLOYED FOR TELEGRAPHIC PURPOSES,"
upon the condition (amongst others) that I, the said William Hickling
Burnett, 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 William Hickling. Burnett, 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 thereof, reference being had to the Drawings here-
unto annexed, that is to say:-
This Invention consists in improvements whereby increased rapidity is pro-
duced in signalling by means of electricity, especially where subterranean or
submarine lines are used, and by some of which the obstructions now caused by
terrestrial, marine, or atmospheric induction, and by static charge and discharge
of the line, are either wholly or partially removed; also in improvements
in parts of the instruments and apparatus used in working telegraphic lines.
My first improvement is shewn in Figure 1 of the accompanying Drawings,
and has for its object to diminish or remove the evil effects of earth and other
accidental currents. Here L is the working line, and L' a second line parallel
to it. At the sending end S¹, both lines when not signalling may be to earth
or not at e', but both must be the same, after going round the instrument I',
as coils in opposite directions. They are both to earth at the receiving end S³,
at e³, after going round the instrument I³, as coils in opposite directions. Now,
wherever earth or other accidental currents set in, as the two lines are exposed
to the same influences similar currents will be formed and balance each other
round the instruments, which are therefore free to make the signals when a
battery current is sent through either line without disturbance or interference
from these causes. Batteries may be inserted between line and earth in order
to carry
out any
of my improvements for diminishing retardation hereafter
described, provided they are so balanced when in the normal state as not to affect
the instruments. By coiling the two lines in opposite directions, round
instruments arranged on the plans hereafter shewn for working two or three
distinct systems of telegraph through one line wire simultaneously, and using

page_text: batteries of unequal forces, I make each of the two lines a working line,
at the same time the instruments of both are quite independent of accidental
currents and of each other.
My next improvements in the mode of working telegraphic lines are shewn
in Figures 2 to 10, and are intended to diminish or obviate the loss of time
in transmitting signals which occurs with the plans at present in use, especially
when the wires are subterranean or submarine. I effect these objects in
various ways.
In some of them two wires at least are required, and I cause
the signalling line to be wholly or partially charged from both ends every
time a current is sent, and when it ceases to be immediately discharged at
both ends to earth. In others which also require two lines, at least one or
both of the lines is or are kept constantly charged. Other modes require only
one line, and generally with a battery at each terminal, and the line is also
always more or less charged.
One arrangement on the first plan named, is shewn in Figure 2, where
a battery P, N, is at the station S³, which in this description I will suppose
to be the sending station, and another battery P¹, N¹, at the second
station S³, which I will suppose to be the receiving station. The poles P
and N are connected by the wire L; the pole P¹ at S³ goes to earth
at e³, as well as through the coils of the instrument I³, to one end of the
line L', which extends to the station S¹, where one end of the coils of the
instrument I¹, is affixed to it. In the normal state, that is when signalling
is not going on, the other end of the coils of I¹ goes to earth at e¹, and the
line L' is completely discharged from both ends, but when a signal has to be
made the connection between L' and earth is broken, and L' is put to N,
when the current rushes into L' at both ends and makes the signal, L' is then
again put to earth and the line is discharged. On retaining the same arrange-
ments at the receiving station S2, both wires may be permanently fixed to
opposite poles at each terminal, and both batteries be normally to earth. In
this state of things no current will be flowing through the signalling line, but
constantly through the other, but if connection with earth is broken at either
end the current will flow into the signalling line at both ends, and will continue
to do so until the pole is again placed to earth, when the signalling line will
discharge at both ends. On causing the line L to join similar poles N, N', of
the two batteries P, N, at station S¹, and P¹, N₁, at station S2, L¹ is the
signalling line, to the ends of which are the coils of the instruments I and I³,
the other ends of which go to the poles P and P¹. The pole P¹ alone goes
to earth. This is the normal state. Signals may be made either by reversing
the battery at the sending end, or by disconnecting L' from P, and putting..

page_text: it to N, or by dispensing altogether with the battery P, N, and keeping L',
normally to earth. I make the signal by putting the two lines in contact.
. An arrangement I use in carrying out the second plan named is shewn in
Figure 3. Here the two lines L, L', are connected at the receiving station S²,
while at the sending station S¹, they go to the opposite poles of a battery P, N.
At the receiving station one end of the coils of an instrument I2, is united to
the junction of the lines L, L', while the other end goes to earth at e. The
current is thus constantly flowing round the two lines, but not through the
instrument I. Signals are made by putting either pole of the battery at S¹,
to earth through the coils of an instrument I', at the same time breaking or
not breaking the line connection with that pole. In carrying out these
systems in most cases I prefer to use a battery at each end of the line, although,
as I have shewn, it is not always absolutely necessary.
One of the arrangements I adopt in carrying out the third plan named is
shewn in Figure 4. In this Figure S may be considered as the sending, and
S the receiving station. At S¹ the battery is very much more powerful than
at S2, and similar poles. are joined by the line L, the other poles going to.
earth. The battery at S¹ must be sufficiently powerful to overcome the battery
at S³, in which case the current will be always flowing from the battery at S¹,
through the battery at S³, in which direction no signal will be formed, but by
cutting off or reversing the battery at S¹, the current will flow into the line.
from the battery at S2, and form a signal..
Another arrangement I sometimes adopt is shewn in Figure 5. This:
arrangement is very similar to the one just described, and similar letters apply
to similar parts, the chief difference. being that an earth connection through a
resistance coil R, which I prefer to be about equal to the resistance of the line,
is placed at some point on the line L. The signals are made in the same
manner as described with reference to Figure 4. I sometimes modify this
arrangement as shewn in Figure 6, in which case instead of a larger battery I
employ two batteries at the sending end, one of which is about equal in power
to that at the receiving end with which it is connected through the line L, by
poles of similar denomination, the other poles going to earth. When a signal
has to be made, a second battery P',. N', is added to P, N, and removed after
the signal is made.. I frequently find the introduction of resistance coils of
great use. One arrangement in which this is done is shown in Figure 7,
where also similar letters apply to similar parts. The N pole of the battery N, P,
at the sending end is connected through the coils of I', the line L and the
coils of I³ with N¹ at S³, but between the end of the coils of the instruments
and. tlie poles of the batteries earth connections are made through resistance

page_text: coils R, R¹, which I prefer to be about equal in resistance to the line. In this
state of things the line is constantly kept discharged, but a circuit exists from
each battery through the resistance coils. Signals are made by reversing at S¹,
or making and breaking between L and N.
Another arrangement is shewn at Figure 8, in which case also similar letters
apply to similar parts. At the receiving station, however, are two batteries
P¹, N, P, N³, joined by a short connection to dissimilar poles, at this.
connection is an earth contact, the other poles are also united by a wire
through one or two resistant coils R, R¹, and the end of the coil of the instru-
ment is connected to this wire where shewn in the Drawing. Signals
are made by reversals at St.
A
A simple arrangement is shewn in Figure 9, where an earth connection
through a resistance coil is introduced in some part of the line which I
prefer to be about the centre. Signals are made by reversals at either
end. The different methods I have explained effect perfectly the objects
intended, but the connection of the wires with the poles of the batteries,
earth, and each other may be considerably varied and yet produce the same
results. I therefore do not confine myself to the particular arrangements
described. I sometimes signalize with the aid of the synchronously moving
wheels described in the Specification of my Patent of May 23rd, 1860,
No. 1271, by causing the line to be put automatically to the battery and
earth or to different poles of the battery alternately, or otherwise at the
receiving end or at both ends simultaneously, signals being made by reversing
or making and breaking by means of the key at the sending end. Some-
times I use batteries of unequal force in order to vary the amount of
retardation.
In Figure 10 I have shewn one of these arrangements. In this Figure
similar letters refer to similar parts, but two circles marked W, W¹, respectively
will be seen towards the ends of the line L near the batteries, these represent
the synchronously moving wheels which alternately put the line to the earth
or battery at both ends. By means of the key the battery at S¹ can be
reversed and signals thus be made. In working long land lines in order
to diminish the retardation of signals, caused by the variable state and the ten-
dency to leakage which increases with the intensity of the current, I prefer
sending the messages step by step at short intervals from fresh batteries, but
in doing so in the ordinary mode of working, a tendency exists for the signals
to become changed in their proportions as they are sent forward with fresh
batteries.
By the improved modes of working next described this evil is removed, and

page_text: signals may be carried on step by step any number of times without any
appreciable change taking place in them. I effect this in one of two ways,
either by so arranging the contacts at each alternate station that at one
station the fresh current is sent on when the armature is called up, and at
the next when it is released and so on alternately, or by using small local
electro-magnets to prolong the current on the system I shall hereafter describe
when speaking of an improved mode of working two or three systems of
telegraph through one wire, and to diminish the irregularities that might arise
from imperfect contacts. I usually keep one end of the fresh step battery to
earth and the other permanently to line, but a short circuit can be made at
each station, and when that is the case the current will not flow through the
line. At each alternate station this short circuit is made or broken each
time that a signal is sent, and I also frequently employ this sort of contact in
other relay instruments as well as in sending keys to lessen the injurious
effects of sparks at the contacts.
An arrangement on the first of these plans is shewn in Figure 11, where
S, S1, S2, S3, S, are five stations joined respectively by the lines L, L, L³, L³.
K at S, is a sending key; P goes to the upper contact of the key and
to the line L, which is continued as coil round the electro-magnet.E,
M, at S, and then goes to earth; when therefore the key K is in its
normal state a short circuit exists between P and N, but when the key is
depressed that short circuit is broken and the current then flows from. P
through the line L round the coils of the electro-magnet E, M', to earth. The
armature A" which is normally on the stop s¹, is then drawn up to the contact
c thus making short circuit between P¹ and N¹. Until this armature is
drawn up the current from P¹ of P¹, N¹, is flowing through L' round the coil
of E, M³, to earth keeping the armature Ar against the contact c, and thus
forming short circuit between P2 and N2 at the next station. At this time
the armature of the electro-magnet E, M³, is back against the stop's, as no
current is passing.through the line L³, on account of the short circuit which
has been formed, but as the short circuit at S³ is now broken, the current
from the battery P³, N³, will be flowing through the line L³ round the coils of
the electro-magnet E, M, keeping the armature A** on the contact c', which
forms short circuit to the battery P, N*, and so on alternately, for any number
of stations. Thus at each alternate station a short circuit is made or broken
when the signal is sent.
An arrangement on the second plan, the details of which may however be
considerably varied without departing from the main features of the Invention,
is shewn in Figure 12, where E, M, is the electro-magnet formed.by the line

page_text: current which comes from the down line D, L, and passes round the coils to
the earth at e. A is its armature, which has no recal spring, but moves with
a slight degree of friction. a, r, is a small additional armature recalled (after
being attracted) by the recal spring r, s. R, E, M, is another electro-magnet
formed by a local current which recals the armature A* against the stop a, and
retains it there in the interval between the passage of line currents.
The armature A* is connected with earth at e, when I use a distributing
battery and the stop p with the up line U, L, so that when the armature is
against the stop p a current is flowing through the down line. The armature
a, r, is connected with one pole of a local battery, the stop p¹, with one end of
the coils of the electro-magnet R, E, M, the other end of which is attached
to the other pole of the local battery N, so that when the armature a, r, is
against the stop p', which is always the case when there is no line current
passing, the local current is always closed round R, E, M, the armature Ar
being retained on the stop a. Now when a line current passes round E, M,
the armature a, r, is called over to the stop 6 and breaks the contact at p¹,
R, E, M, ceases to be an electro-magnet, and the armature A*, is called against
the stop p, where it remains until recalled by R, E, M, which may be after
any required interval. When the line current ceases a, r, is thrown against
p', and R, E, M, becomes an electro-magnet, recalling A at the required time
from the stop p. By having an insulated wire, shewn at C between the stops
p', and R, E, M, so coiled and arranged as to require a certain time to charge
it before arriving at R, E, M, and means of adjusting its length, the interval
between the contact of a, r, and p¹, and the formation of the electro-magnet
R, E, M, and the consequent recal of A* can be prolonged any required time.
This self-compensating relay will only be required at intervals when the
pulsation has a tendency to become too much shortened, the ordinary relay
being generally used. Of course also by adopting the system just explained
of only working through short distances, with the same current, the leakage
and resistance will be so much reduced that instruments may easily be worked
without relay batteries.
My next improvements have for their object the simultaneous working of
two or even three distinct systems of telegraph through one line wire in such
manner that the instruments shall be made to act in part from one and in
part from the other end of the line, or all the instruments at one end from
the other end, whilst, if required, the messages sent from either or both ends
are also being delivered at any intermediate station or stations, or that while
one or more powers of the line is or are being employed between the terminals,
the other power or powers of the line is or are transmitting messages between

page_text: intermediate stations, or between intermediate stations and the terminals. To
produce these effects, I use currents of unequal force or of different qualities
to deliver the different messages, and I sometimes make all the currents flow
in one direction, and sometimes part in one and part in the opposite direction,
and the intended signals are caused by the contacts made or broken as
different armatures are moved by the varying currents. To work two systems
on this plan I require to be able to send along the line three varieties of
current, one of which is made to set in action the first instrument, another
the second, and a third both instruments. To work three systems I require
to use seven varieties of current. One, two, and three varieties set in action
separate instruments one, two, and three; a fourth variety sets in action
instruments one and two together; a fifth,variety sets in action instruments
two and three together; a sixth variety sets in action instruments one and
three together; and a seventh variety sets all three in action together.
The description just given is only applicable to those instruments which
are worked with line currents always flowing in one direction, but it is
sometimes convenient to use one or both powers of the line to work instru
ments in which the current flows in alternating directions. To work one
power of the line with alternating currents, and the other with currents, all
in one direction, I use five varieties of current. The first works the two
direction instrument alone one way, the second works it alone the other way,
the third works the second instrument alone; the fourth works the first
instrument the other way at the same time as the second instrument, and
the fifth works the first instrument the other way at the same time as the
second instrument. Of course a double key will be required to work the
alternating current instrument, and I make proper arrangements of contacts
in putting down these keys so as to send currents of the required force and
quality, and I sometimes use the line current direct to work the alternating
instrument and the relay to work the one direction instrument, or I work both
by the relay, or both by the line current. To work both instruments with
alternating currents I require eight varieties of electric force, and I sometimes
work one of the instruments directly by the line currents, and the other by
means of a relay local battery, or both by means of the relay battery, a double
key being required to work each instrument, sending, according to the com-
bination of their motions, the required line currents. I compose the relays
of electro-magnets and armatures varying in number according to circumstances;
the armatures are sometimes made of soft iron, and sometimes permanent
magnets, or the relays are partly or wholly composed of galvanometers.
The foregoing is a general description of the system I employ, but certain

page_text: obstacles to their proper working exist in practice, and constant errors will
occur without means are adopted to prevent them, which means form a most
important part of my Invention. In cases where currents flowing all in one
direction are used when a signal has been made with one, and then it is
wished to maintain that signal and at the same time to make a signal with
the other instrument, a different armature is brought into action, and unless
some sustaining power on the signal were interposed a break would take
place during the change in the first signal. Likewise when using currents
flowing in opposite directions a certain interval of time is consumed while
demagnetizing the instruments in one direction, and remagnetizing them in
the other direction, during which the signal would be broken without this
compensating apparatus. This compensating apparatus is that to which I
have referred when speaking of maintaining the proper duration of the signals
sent, and consists of a small local relay, electro-magnet, and magnets, which
require to be demagnetized and magnetised before a signal can be made or
broken so that the state of the signal is maintained as long as the time
occupied by the break caused by the change in the line current.
Another source of error is the persistent magnetism which attaches to
electro-magnets when a weak current is sent after a strong one, which renders
it extremely difficult to adjust the force of the recal springs, so that the
armatures shall fall back when they ought. I overcome this defect by means
of small local batteries which are caused to send currents, kept of any required
degree of force by rheostats round coils in opposite directions to the line
currents, either permanently or only when the line current is sent so as to
modify the forces of the line currents, or I use galvanometer relays which are
not equally subject to persistent magnetic effects, especially when arranged as
the relays hereinafter described. If it is not required for the home instrument
to shew the signal sent by means of the keys, I cause balancing local currents
to go round separate coils in the instrument, whereby the effect of the home
line current sent is neutralized, and the distant current alone indicates, but
if it be desired that both the home and distant signal should indicate by
means of the rheostat, I send a local current at the same time as the line
current of a force only equal to the difference of the same current at the two
ends of the line. When I require either or all of the messages sent to be
delivered at any intermediate station or stations also I place relays at those
stations, constructed upon the same principles as those at the terminals; but
if I require any message to go no further than a certain intermediate station
but the other message or messages to travel further, I send all the currents
to earth at that station, and by means of a repeating relay send on the

page_text: travelling currents from a fresh battery, and also by having a proper
manipulating key or keys at that station send on, if required, a fresh message
or messages in lieu of those stopped.
In Figure 13, I shew a top view, and in Figure 14, a side view of four
armatures worked by electro-magnets formed by the line current, as well as
the compensating electro-magnets, which I have alluded to, being one of the
best arrangements I adopt in working two systems of telegraphs through one
line by means of alternating currents. In this case all the armatures are
permanent magnets, they are shewn in the figure against the back stops,
to which they are constantly solicited by the recal springs r, s. The
currents that are sent are a positive one of one or two degrees of force,
a negative one of one degree of force, and a negative one of two. degrees
of force. The positive current works one instrument I¹, by means of
the compensating electro-magnets L, E, M. The negative current of
two degrees of force works the second instrument I2, and the negative
current of one degree of force works both instruments. Armature 1 is
called over from the stop s, to the stop s', by the passage of the positive
current: Armatures 2 and 4 are called over by all negative currents, but
armature 3 only by the negative current of two degrees of force. Armature 5
vibrates between the two local electro-magnets L, E, M, and is also by
preference a permanent magnet. These electro-magnets are formed by a
small local battery, the directions of the poles of which are indicated by S, P,
and S, N. The instruments I¹ and I are worked by another local battery, the
direction of the poles of which is indicated by the letters I, P, and I, N. The
armature 1 is connected with the positive pole of the small battery S, P,
and the armatures 4 and 5 with I, P, the positive pole of the instrument
battery. In the normal condition of things, which is that shewn in the
Figures, the armature 1 is on the stop s, which stop is connected by a wire
with the armature 2, which is pressed against the stop s³. In this state of
things it will be seen that the current is flowing from S, P, up 1 by the stop s,
up 2, to the stop s³, and round the coils of the left hand local electro-magnet
L, E, M, to S, N, retaining the armature 5 upon the stops. In this position
no current is flowing round the instrument I', but if a positive current is
sent along the line, the armature 1 is called over against the stop s¹, whence
the current S, P, is conveyed by a wire to the armature 3. The contact
between s and 1 being broken the current ceases to flow round the left hand
local electro-magnet, but flows instead from a stop s', through a wire up the
armature 3 to the stop s', and round the coils of the right hand electro-magnet
L, E, M, to S, N, calling over the armature 5 on to the stop s. As 5 is

page_text: connected with I, P, the current will flow from s', round 12, to I, N, making
the signal with that instrument. If now a single force negative current is
sent the armature 1 will fall back upon the stop s, and the armature 2 will
be drawn on the stop s². During this change there would be a break in the
signal at I, were it not for the compensating electro-magnet L, E, M, but as
when armature 1 falls away froin s¹ on to s, a certain time is required to
demagnetize the right hand electro-magnet L, E, M, and magnetize the left
hand one the signal will not be broken for some little time, in fact not before
armature has arrived on the stop s, when the signal at I', will be main-
tained. As all negative currents call over the armature 4 against the stop s6,
a signal will also be made at 12, as I, P, will flow up 4 through so, round I
to I, N. If, instead of the single force negative current, a double force
negative current were sent, armatures 2, 3, and 4 would all be called
over. In this case the signal would only be made at I2 the contact
between 3 and s being broken, the right-hand electro-magnet L, E, M,
will cease to be a magnet, but as armature 3, falls upon the stop s the
current from S, P, will flow round the left hand electro-magnet L, E, M,
to S, N, calling over armature 5 against the stop s8, thus breaking the
signal at I¹.
I have not thought it necessary to shew the line electro-
magnets as they may be arranged in any convenient manner.
I have already.
stated that another source of error when working currents of unequal force,
is the persistent magnetism, which remains after a strong current, which has
been sent is followed by a weak one of the same denomination, and that I
overcome the difficulty by means of a local current sent through coils in
an opposite direction to that of the line current. Figure 14 shews a
convenient mode I adopt to carry out this plan. I here shew it without
the compensating electro-magnets last described, but from the description
just given it will be fully understood how they are introduced. I here
also shew the electro-magnets for a relay of two systems worked by
opposing currents along the line on this principle; E, M', is the electro-
magnet having coils round its cores, through which a current is made to
pass from a small local battery as well as coils through which the line
current is made to pass; and E, M², is another electro-magnet formed
entirely by the line current. The local current is thrown round its coils at
E, M', at the same time as the line current, but in an opposite direction, and
by means of the rheostat it is made to balance the single force line current,
so that when a single force current is sent along the line in either direction,
no electro-magnet is formed at E, M, and the armature 3 is not attracted.
Armatures 1 and 2 are permanent magnets, and one of them is drawn over by

page_text: every line current, according to its direction. The other part of the figure
shews the armatures separately from the electro-magnets, in order better to
point out the contacts which take place according to the line current sent.
The line current comes from the down line D, L, round E, M³, coils then
round E, M¹, coils to up line U, L. 1, 2, 3, are the armatures, 1 and 2
being magnets, and .3 soft iron. Armature 1 is attracted by the P current,
2 by the N currents, and 3 by the double current. In their normal state the
armatures are on the stops shewn in the Figure, videlicit, 1 on the stop s¹,
2 on the stops, and 3 on the stops s' and so. When armature 1 is called
over by the P line current, nothing else is moved, and it comes on stops s²
and s³. Two insulated metals attached to this armature come respectively on
these stops. One of these metals is connected by the wire w with p, the
position pole of a small local battery whose current is made to flow round the
electro-magnet E, M', in an opposite direction to the line current. This
P current flows by the stops through the wire w round E, M¹, by the stop s*,
down armature 2 to the negative pole n, preventing the electro-magnet E, M²,
calling over the armature 3. At the same time the P current from another
local battery flows by wire w' up the other metal to s³, through w¹ round the
instrument I¹ to the N pole, thus setting in action that instrument only. If
a single N current is sent through the line, armature 2 is attracted, and the
current from the N pole of the small battery flows up one metal of armature 2
to the stop s³, round E, M³, (balancing the line current,) by s¹ down armature 1
to p. At the same time the current from the P pole of the local battery
which works the instruments, goes up the wire w¹ to the insulated stop s6,
through the wire w¹ up armature 3 to the stops s', s, by 88 round I¹ to N, and
by si round the instrument. I to N, thus moving both instruments. If the two
force N current is sent along the line, both armatures 2 and 3 are called over
as the line current is stronger than the local current round E, M²; and the
P local current flows up armature 2 to the stop se through w¹ up armature 3
to the stops, round the instrument I2 to N, thus acting on that instrument
alone. I also sometimes at sending stations use the keys themselves instead
of the contacts of the armature to throw currents from the small local batteries
round the relay, in order to balance the effect of the line current or currents
sent upon the home instruments, so that they may only shew the messages
from other parts of the line. The mode of carrying this into effect will be
easily understood from the previous descriptions. I arrange for three
instruments on similar principles when opposing currents are sent, but some-
what differently when all the line currents are in the same direction. The
arrangement of the contacts, the number of electro-magnets, and their arma-

page_text: tures, and the force and direction of the small relay currents may be greatly
varied without departing from the main feature of this part of my Invention,
which is the modification of the forces of the line currents on the cores of the
electro-magnets by counteracting relay currents, and thereby diminishing the
number of discriminative forces required in the recal springs, and the evil
effects of permanent magnetism. When working three systems with reversed
currents, the plan I prefer is shewn in Figure 15, but when working three
systems with line currents all in one direction, the plan I prefer to adopt is
that shewn in Figure 16.
In Figure 15 are shewn in top view three electro-magnets E, M, E, M, E, M³,
with their respective armatures 1, 2, 3, 4, and 5. All these electro-magnets
have coils for the passage of the line currents through them, and in addition
the electro-magnets E, M', E, M³, have coils for the passage of currents from
small local batteries. The line currents which may arrive constitute seven
varieties, videlicit, three positive and four negative currents, the former of one,
two, and three degrees of force, and the latter of one, two, three, and four
degrees of force. The electro-magnet E, M², has a local current adjusted by
a rheostat, permanently going round its cores, the direction and force of
which is made exactly to balance the three-power N line current, and as the
armature 5 is only attracted by an N current, it is only when N four power
comes along the line that that armature will be called over. Electro-
magnet E, M, has a local current of one degree of force thrown, round it in
an opposite direction to the line current, whenever a line current passes in the
manner hereafter explained, and the recal springs of its two soft iron armatures
are so arranged that armature 3 is called over by currents of three or more
degrees of force, while armature 4 is called over by currents of two or more
degrees of force. Electro-magnet E, M, has two armatures, of which
armature 1 is called over by all P currents, and armature 2 by all N currents.
In the other part of the Figure I shew the armatures 1 and 2 detached, in
order better to explain the contacts for throwing on local currents. In the
Drawing the armatures are in their normal positions; D, L, is the down line,
and U, L, the up line. In this normal position the line current has two roads
open from the down line D, L, to the up line U, L, after passing round the
coils of electro-magnet E, M, videlicit, a short circuit through armature 1 by
the stop s¹, wire w, armature 2, and the stop s to the up line U, L, or through
the coils round the cores of electro-magnets E, M', and E, M, also to U; L.
Of course the line current will select the short circuit until it is broken, which
will be the case the moment either armature 1 or 2 is drawn over by the
electro-magnet E, M, when it will go round the electro-magnets E, M', and

page_text: في
E, M, instead of by the short circuit. I have already stated that a current
from a small local battery is constantly flowing round the electro-magnet E, M³,
but when a line current passes a small local current of one degree of force is
also made to flow in an opposite direction to that line current round
E, M¹. This takes place as follows:-The armature 1 is connected with
one pole, and the armature 2 with the other pole of the small local battery.
If armature 1 is called over, the local current will flow from one pole through
the stop
by the wire w¹, round E, M¹, by the stop s³, and the armature 2 to
the other pole. If armature 2 is called over the current will flow through the
stops, the wire w¹ round P, N', in an opposite direction, the wire w', the
stop so, and the armature 1 to the other pole. The local battery current
which works the instruments will be set in action according to the contact
made and broken by the different line currents, on the same principle that I
have already explained. When the line current all flow in one direction, they
will come with seven degrees of force along the line, but their varying action
on the instruments will be very much modified by the relay counter currents.
One of the simplest and best arrangements is shewn in Figure 16. I will
suppose the line current sent to be one of seven degrees of force flowing in
one direction, in order to work the desired instrument or instruments. In
this case I consider it better to use seven armatures, as shewn, and three
electro-magnets, although it could be arranged with only one electro-magnet,
but it would be difficult to get it to work as perfectly as with the arrangement
shewn. Here, as in Figure 15, E, M, E, M, and E, M³, are three electro-
magnets, but E, M, has three armatures, 1, 2, and 3; E, M³, has two
armatures, 4 and 5; and E, M², two armatures, 6 and 7, and round all these
electro-magnets are two sets of coils, one set for the line current, and the
other set for the current from a local battery or batteries. These local
currents are continually flowing, and are so adjusted by rheostat, or otherwise,
that the local currents round E, M, and E, M', exactly balance line currents
of three degrees of force, and those round E, M³, a line current of five
degrees of force. All these armatures are magnets. Armatures 1, 2, and 3,
are only attracted by the local current, and when no line current is sent, they
are kept against their normal stops, and by properly adjusting the force of the
springs r, s, are released by different line currents, and make the required
line currents.
contacts, but armatures 4, 5, 6, and 7, are only attracted
These electro-magnets all have pole pieces, between which the armatures play,
as shewn at E, M, Figure 15. At Figure 16 the seven armatures are shewn
in their normal position with their recal springs r, s, and I will explain with
reference to this Figure the various contacts which take place according to

page_text: the line current sent.
Armature 1 is drawn over by all P currents, armature
2 by all P currents of two degrees of force and upwards, armature 3 by all
P currents of three degree of force and upwards, and so on to armature 7,
which is only drawn over by a P current of seven degrees of force. In
noticing, therefore, the contacts which take place with line currents of
<lifferent degrees of force, it will be sent that each one works a different
instrument, or a different group of instruments. Thus a P line current of
one degree of strength works I¹ only; a P line current of two degrees of
strength works I2 only; a P line current of three degrees of strength works
both I and I2; a P line current of four degrees of strength works 13; a
P line current of five degrees of strength work I' and I³; a P line current
of six degrees of strength works 12 and 13; and a P line current of seven
degrees of strength works I, I, and I³. But notwithstanding that the line
current has seven different degrees of force, in consequence of the neutralizing
effect of the local currents, seven degrees of force will not be required in the
recal springs, but very much less. The description just given only applies to
those instruments which are worked with line currents all in one direction.
Figure 17 shews an arrangement which I adopt when one of the instru-
ments is worked by currents always in one direction, as, for instance, in the
Morse instrument, and the other instrument by alternating currents, as in
the needle instrument. In this case I find it most convenient to work the
needle instrument direct by means of the line current, and the Morse instru-
iment with the assistance of a local relay current. I might use for the Morse
instrument relay electro-magnets similar in their arrangement to those I
have just described; but I prefer galvanometers, or the improved axial relays
hereafter explained and shewn in Figures 24 to 26. Five needles of this
description are used to form the relay, and I require five varieties of current
to work it, which may conveniently be the following, videlicit, to work the
single direction instrument only a negative current of one degree of force, to
work the two direction instrument one way a negative current of two degrees
of force, and to work it the other way a positive current of two degrees of
force; to work both the single direction and the double direction instruments
one way a negative current of three degrees of force, and to work both the
single direction and the double direction instruments the other way a positive
current of one degree of force. In this case as in the other cases, I have
not thought it necessary to shew the relay needles themselves, and their coils,
as they may be arranged in any convenient manner, but I only shew the
contact pieces; c¹ to c respectively are the contact pieces of five of the axial
relay needles of the description shewn in Figures 24 to 26, hereafter described,

page_text: as by this arrangement it is easier to trace the direction of the currents and
the position of the currents. 1' is the needle instrument; I, the Morse
instrument; L, E, M, are the small local compensating electro-magnets
already referred to, and A' is an armature which vibrates between them,
and by its movements works the instrument I. All the line currents pass
round I, as well as round the coils of all the relay needles. The recal
weights of I are so adjusted that a negative current of a single degree of
force will not have sufficient power to move the needle, but all the other
currents, whether positive or negative, will do so, and the relay needles are so
arranged as to the contacts that the negative currents of one and three degrees
of force and the positive current of one degree of force shall cause I² to work,
but neither the positive nor negative current of two degrees of of force is enabled
to do so. The needles at the contacts c¹ and c² are so adjusted by their
counterweights as to be worked by a line current of any degree of force; the
needles of the contacts of c³ and c* only by currents of two or more. degrees of
force, and the needle. of the contact c³ only by currents of three or more
degrees of force. In the normal state, that is, when no line current is passing,
each of the contacts is kept by counterweights or otherwise upon one of the
fixed stops, all positive currents having a tendency to move the contacts to the
right, and all negative currents to move them to the left. The contact
piece c', which is normally on the stop s', is connected by a wire with the
positive pole S, P, of a small local battery. When no line current is passing,
that from S, P, will go from c¹ through s¹ by its support, and the wire w to
the contact piece c³, thence by the stop s, and a wire w round the coils of the
left-hand electro-magnet L, E, M, to S, N, the negative pole. of the same
small local battery, keeping the armature A* against. the stop s". The
armature A' is connected with the positive pole I, P, of the battery, which
works the instrument 13. When the armature A ceases to be called over by
the left-hand electro-magnet L, E, M, and is, on the contrary, called over by
the right-hand electro-magnet L, E, M, on to the stop s, then the current
from I, P, will flow round the instrument I2 to I, N, the negative pole of the
same battery, and make a signal. I now proceed to trace the action of the
various line currents upon the instrument I³. When a positive current of one
degree of force is sent the needle of the contact c¹ alone will be moved, those
of the contacts c2, c, and c being more firmly kept against their respective
fixed stops. The current from S, P, will thus cease to flow through s¹, and
the various contacts which previously existed, causing the current to flow round
the left-hand electro-magnet L, E, M, will cease, and the left-hand electro-
magnet L, E, M, will become demagnetized, and no longer attract the arma-

page_text: ture A, but instead the current will flow through s² down its support, and the
wire w to the contact piece c³, stop s³, its support, and the wire w to the
contact piece c', the stop s³, round the coils of the right-hand electro-magnet
L, E, M, to S, N, the negative pole of that battery calling over the armature
A to the stops, and thus forming a signal. If instead of a positive current
of one degree of force a negative current of similar force had been sent, c'
would have remained on the stop s³, but c³ would have been called over to to the
stop s, thus unmaking the left-hand electro-magnet L, E, M, and making the
right-hand electro-magnet, causing the signal in the same way, as will be seen
by tracing the direction of the wires w, and noticing the various contacts. If,
instead of either of the currents just mentioned a double force positive current
were sent, not only would c¹ be brought against s2, but would also be
brought against se, in which positions no signal would be made at I; this
will be understood by the following description:-The current from S, P, will
cease to flow from c¹ through the stop s¹ to c³, but will flow instead to s³ by
the wire w to c³, then to so by the wire w to c³, thence- by $10 round the coils
of the left-hand electro-magnet L, E, M, keeping the armature A* against the
dead stop s, where no signal is made. If a double force negative current be
sent not only will c² be brought against the stop s³, but c' also will be brought
against the stop s7, and the effect just described will also ensue, as may be
easily traced in the Figure. If instead of the double-force negative current a
treble force negative current be sent, not only will c² and c be moved against
their stops, but also will be moved against the stop so, and by breaking
contact with s¹0, will prevent the current flowing round the left-hand electro-
magnet L, E, M, and cause it to pass through so its support, and the wire w,
round the coils of the right-hand electro-magnet L, E, M, to S, N, thus
calling over the armature to the stop s¹, and forming a signal at I².
Figure 18 shews the arrangement I generally employ to work two needles,
each with alternating currents. In this case I usually work one of these needles
entirely by means of the line current, and the other partly by means of the line
current and partly by means of a local current. I require eight distinct varieties
of current, videlicit, four positive and four negative, each kind of four different
degrees of force. The first needle, which in the Figure is marked I¹, is alone
worked by positive and negative currents of three degrees of force, but not at all
by currents of one degree of force. By currents of two and four degrees of force
it is worked at the same time as the second needle I2; I², on the contrary, is
worked by currents in either direction, of one or four degrees of force, but is not
moved by currents of three degrees of force, whereas currents of two degrees
of force are made to work it in an opposite direction to that which is usually

page_text: produced by the line current sent. In this Figure I only shew the contact pieces
of the relays, as in Figure 17. The current is made to flow from the down
line D, L, round I', then round the coils of the relay, and then round 12 to
U, L. In order that I¹ may not indicate with the weakest force currents
which are exclusively reserved for 12, the needle is so arranged with counter-
balance weights that the weakest force will not move it, but any force exceeding
one degree will do so, as is intended; I³, on the contrary, requires to be
worked by the weakest degree of force in either direction, as well as by the
strongest, but not by those of three degrees of force, while currents of two
degrees of force require to indicate in a reverse direction. The manner in
which this is effected will be seen on reference to the Drawing of the relay,
which is arranged to throw a local current, regulated as to its force by rheostat
or otherwise round other coils of I in an opposite direction to the line current
sent. It will be seen that c¹ is connected by wire to L, P, the positive pole of
the local battery, while the contact piece c³ is united with the negative pole of
the same battery. The relay is shewn in its normal position, that is, its
position when no line current is passing. In this state the battery L, P, L, N,
is on short circuit as the current flows from c¹ to s' down its support by w to
s', c, and L, N. The support of the stop s is connected with one end of a
coil, which goes round I, and the other end of which goes to L, N, and the
support of the stop s³ is connected with one end of another coil, which goes
round I, and the other end of which goes to L, P. If now a positive or
negative current of one degree of force be sent the counterbalance weights of
the relay needles of c¹ and c² are too heavy for them to be moved, but any
current of two or more degrees of force will call one of them over and according
to the direction of the line current sent will cause a local current adjusted so
as to balance the three degree line current to flow in an opposite direction
round I, breaking at the same time the short circuit. It will thus be seen,
that the line currents of three degrees of force, which are only intended to work
1', will be completely neutralized on 12. If the line current be of two degrees
of force, the local current having three degrees of force, will predominate, and
cause the instrument I to indicate in an opposite direction to that which it
would indicate if influenced merely by the line current sent. If currents of
four degrees of force are sent along the line, although local counter currents of
three degrees of force are at the same time sent round I2, the line current will
predominate, and cause the instrument 12 to move in the right direction. On
reference to the Figure, it will be perceived, that when c¹ is called over the
local current will flow round 12 in one direction, and that when is called
over it will flow in the opposite direction. Of course the small compensating

page_text: electro-magnets already described may be interposed between the instrument
and the relay when necessary.
I now proceed to describe some of the arrangements of manipulators which
I employ to send the required currents for the different instruments.
Figure 19 shews an arrangement well adapted to work two Morse instru-
ments. In this case, one instrument is worked by a single force positive
current, the other by a double force negative current, and both instruments by
a single force negative current. A is the key which works the first instrument,
and B, the key which works the second instrument. I use two batteries
N, P, N, P, the latter of which is of double the force in tension of the
former. On referring to the Figure, it will be seen that N goes to earth
at E, and that P goes to the stud s of the key A by means of the wire w. It
will also be perceived that the earth E is connected with the upper contact
piece a, and through the metal pin 6 with the lower contact piece c of the
key A; the spring c is also connected by the wire w¹ with the upper contact
piece d of the key B, and by means of the pin and the lower spring g with
the line at L; Ps of the larger battery is also connected with c by the wire w³,
and consequently with earth when the key A is not depressed, and N² is con-
nected by a wire w³ with the studs of the
If now the key A be
depressed alone, the stud s will separate the
and c, and consequently
will cut off the connection between P2 and earth, but the positive current
from P will flow through the wire w¹, d, f, and g, to the line L, and as N goes
to earth a single force positive current will go through the line and work the
first instrument only. If the key B be depressed alone the current from N³
will flow through the stud s' and 9 to L, at the same time cutting off the
connection between d and earth, and at the same time the current from P2 will
flow through c, b, and a to E earth. Thus a double force negative current
will go through the line and work the second instrument only. When both
keys are put down together, a current will flow from N2 through s¹ to L at the
key B, and it will flow from P2 through c and s to P, N being constantly to
earth. In this state of things we have only a single negative current going
through the line which works both instruments.
key B.
pieces a
Figure 20 shews the arrangement of keys and batteries I usually adopt
when working one Morse instrument and one needle instrument in both
directions. A is the key which works the Morse instrument, B the key which
works the needle instrument one way, and C that which works it the other way.
I have here also two batteries P, N, and P2, N2, the latter having double the
force of the former. P goes to earth at E, and N through the wire w¹ to the
studs of the key A. P² goes by the wire w³ to the stud s' of the key B, and

page_text: N2 by the wire w to the stud s² of the key C, the wire w³ being in contact
on its way with wire wat o, when the key B is in its normal position, and the
wire w' being in contact with the wire wat o', when the key Cis in its normal
position. If the key A be depressed alone, the N current of the small battery
will flow through s, c, w', h, i, j, d, f, g, to L line, and as P goes to earth
permanently, a single force negative current will flow along the line, and work
the Morse instrument alone. If the key B be depressed alone, the contact at o
will be broken, and the current from P will flow through s¹ to g and L line,
whereas the N2 current will flow through w, the contact o¹, the wire wº, e, b,
and a, to E earth; thus a double force positive current will go along the line,
working the needle instrument one way. If instead of the key B, the key C
be depressed, the contact at o¹ will be broken, and the current will flow
from N, through s², j, w², d, f, and g, to L line, and at the same time the
current from P2 will flow through w³ by the contact o, w, c, b, and a, to E earth,
sending a double force negative current along the line and working the needle
instrument the other way. If A and B be put down together, the current will
flow from P through the wire w³ to L line; whereas, the current from N2 will
flow through the contact o¹, w, and c to s and N, and as P goes to earth, a
positive current of one degree of force, which is the resultant of the two
batteries will go along the line and work both the Morse instrument and
needle instrument one way. If instead of B, the key C be put down at the
same time as A, the contact will be broken at o' and the current will flow
from N2 through s², j, w², d, f, g, to L line. At the same time the current will
flow from P2 through o by w³, c, and s to N, and as P goes to earth, a negative
current of three degrees of force will go along the line and work the Morse
instrument and the needle instrument the other way. By looking at the
keys B and C it will be perceived that B turns on an axis at x, and Con
a similar axis at x¹.
In Figure 21 I shew an arrangement of keys and batteries, which I usually
employ to work two needles with alternating currents. A and B are the keys
that work one of these needles; C and D are those which work the other; P, N,
is a battery of one degree of force; P³, N³, another battery of three degrees
of force; x, x, x², and ³, are the axes on which the
current from the small battery goes by the wire w to the
and also by the wire w³ to the contact o¹ of the key B.
keys turn. The P
studs of the key A,
The N pole of that
key B, and also by
battery is connected by the wire w² to the stud s¹ of the
the wire w³ to the contact o of the key A. The pole P³ is connected by a
wire with the studs of the key D, making contact on its passage at o³ with
a wire from c, when the key is in its normal state. Ns is connected by a wire

page_text: with the stud s² of the key C, making in its passage, when in its normal state,
contact at o with a wire from c. If now the key A be depressed the stud s
will break the contact between a and c, and make contact between the P pole
through c, the wire w', k, l, m, the wire w³, h, i, j, to L line, and at the same
time the N pole makes a contact at o with E earth. Thus a single force
positive current will go along the line, and work one of the needles one way.
If instead of A the key B be depressed, the N current of the small battery
will go to the stud s¹ of the key B, and thence through g, a wire wo, a, b, c,
by the wire w', k, l, m, the wire w³, h, i, j, to L line. At the same time
contact is made from the P pole at o¹ with E earth. Thus a negative current
of one degree of force will go along the line, and work the first needle the
other way. If the key C be depressed alone contact will be broken at o², and
the current will flow from N³ to the stud s² of the key C, and thence by j to
L line. At the same time the current will pass from P by the contact o³ of
the key D to c, d, a, by wire us to g, f, d, and to E earth. Thus a negative.
current of three degrees of force will go along the line, and work the other
instrument one way. If, instead of C, D be depressed alone, the current will
flow from P3 by a wire w' to the stud sa of the key D by m, the wire w³ h, i, j,
to L line, the contact at o being broken; at the same time the current from N³
will flow through the contact o³, and the wire w', c, b, a, the wire we, g, f, d, to E
earth, thus sending the three-force positive current along the line working the
second needle instrument the other way. If the keys A and C be both depressed
together the contact will be broken at o³, and made with earth at o; the result
will be that the current from N³ will go through s³, the stud of the key C to j
and L line, while the current from P³ will flow through the contact o³, by the
wire w to c, the studs of the key A to P, and from N by the wire w³ and the
contact o to E earth. Thus a positive current of two degrees of force will go
along the line, and work both the instruments one way. If the key B be
depressed at the same time as C, a double force negative current will go along
the line and work the first needle the other way, and the second needle the
same way as before. If now the keys A and D be depressed together the
contact with os will be broken, and that at o made. The current from P³ will
therefore go through the stud 3 of the key D to m, w³, h, i, and j to L line,
whilst the current from N³ will go by the contact o², the wire w³, c, and s to P,
and the current from N go at the same time by the wire w³, and the contact o
to E earth, thus sending a positive current of four degrees of force along the
line working both instruments one way. If the keys B and D be depressed
together, it will be perceived by following the direction of the wires, that a
positive current of four degrees of force will be sent along the line work-

page_text: ing the first instrument in another way, and the second one in the same
direction.
Figure 21, A shews in side view another mode of connecting keys and
batteries, by which seven varieties of currents are sent along the line, as
various combinations of keys are depressed, and by which three Morse instru-
ments can be worked with distinct messages simultaneously. There are three
batteries, P, N, P¹, N1, P2, N2, of three different degrees of force, videlicit,
P, N, of one P¹, N¹, of two, and P2, N2, of four degrees of force; and in the
arrangement I am about to explain, the currents from P, N, and P¹, N¹, go
through the line in one direction, and that from P2, N2, in the other direction
when sent by a single key, although I sometimes make these all go in the same
direction. A is the key which sends the current of P, N, when alone
depressed, and works instrument 1; B, that which sends the current of P¹, N¹,
and works the instrument 2; and C, that which sends the current of P, N%,
and works instrument 3. When 2 or more keys are depressed together the
resultant of their batteries is sent. Thus, A sends one positive, B two positive,
A and B together three positive, C four negative, A and C together three
negative, B and C together two negative, and A, B, and C together one
negative current; and these currents work the instruments which correspond
with the particular keys. After any key has been depressed it is brought back
to its normal state by means of its recal spring r, s. After the explanation
just given it will be easy to trace the force and direction of the current sent
by observing the contacts made and broken when any key or keys is or are
depressed.
My next improvements are in relay instruments, and have for their object
the power of working with extremely minute and weak currents. The
improvements are various, and are not only in electro-magnet relays, but also
in galvanometer relays. In one variety of the electro-magnet relay I have no
recal spring, but the movable armatures, which are made very light, and which
may be either of soft iron or permanent magnets, are recalled at the right
time by weak local currents adjusted by rheostat or otherwise; and these local
currents are made to come into action either immediately on the cessation of
the line current, or after any required interval by means of the wheels
described in the Specification of my Patent of May 23rd, 1860, Number 1271.
Figure 22 is a section of this electro-magnet relay taken through one of the
arms of the electro-magnets E, M; E, M', are two electro-magnets, and A* is
the armature which vibrates between them; E, M, is the electro-magnet
formed exclusively by the line current; E, M', is the recal electro-magnet;
c, c, are the soft iron cores; a in both electro-magnets is the space occupied by

page_text: the coils of the line current; 6, in the electro-magnet E, M', is the space
occupied by the coils of the local battery. When it is intended to recal the
armature immediately after the line pulsation ceases, the local current is kept
continually flowing round these coils, and consequently retains the arma-
ture A against the stop s. When, however, a line current is sent, it is made
to flow round the coils of the electro-magnet E, M¹, in an opposite direction
to the local current that flows round the coils at b, thus neutralizing its effect,
and causing E, M³, to cease to be an electro-magnet, and as at the same time
the line current flows round the coils of E, M, at a, E, M, becomes an electro-
magnet, and attracts the armature A" against the stop s', thereby forming a
signal at the instrument I, because A is connected with the positive pole I, P,
of the local battery which works the instrument, while s¹ is connected with
one end of the coils of the instrument I, the other end of which goes to the
negative pole of the same battery I, N; as soon as the line current ceases
E, M', again becomes an electro-magnet, whilst E, M, is so no longer, and
the armature is again recalled on to the dead stop s.
In another variety I use a spring and a local current to overcome it, and
the force of that current may be made to balance or slightly surpass that of
the spring, so that the weakest line current shall make the spring pre-
dominate, and so form a signal. This arrangement is shewn in Figure 23.
E, M, is an electro-magnet; A* its armature solicited against the stop s¹ by
the recal spring r,s; c is the core of this electro-magnet; 6 is the space occu-
pied by the coils of the local current, and a that occupied by the coils of the
line current. The force of the local current round the coils of 6 is so adjusted
with reference to that of the recal spring r, s, as to cause the armature A* to
be normally against the stop s. When, however, à line current is sent, as it
is made to flow in an opposite direction to the current which flows through
the coils of b, the effects of that current become neutralized or greatly
weakened, and the attraction of E, M, either ceases or is greatly reduced,
allowing the recal spring r, s, to force the armature A* against s', and thus
form a signal at I. The arrangement of the local current which works the
instrument is similar to that already described. At the cessation of the line
current the armature A is again called over against the dead stops.
In another variety, instead of a local current I use a permanent magnet, to
the poles of which pieces of soft iron are attached, which form the cores of the
line coils, and the line current is so sent as to diminish the magnetism of
these cores, and thus cause the spring to make a signal in the manner already
described.
My improvements in galvanometer relays and instruments have also the

page_text: advantage of requiring much less wire in the coils than is usually employed.
The magnetic needle is either suspended horizontally or vertically. In the
former case the poles are usually bent downwards at right angles, and are
made to enter the axes of coils of wire through which the line current passes,
and the action on the poles of the needle is axial. In the latter case the
needle is formed somewhat like the letter Z, and the poles enter into the
axes of coils. Instead of or in conjunction with a slightly preponderating
weight I use a soft-iron pin acting on one of the poles of another permanent
magnet fixed on the same shaft as the needle, by altering the distance of
which pin I increase or decrease the power of recal.
Figure 24 shews the first of these varieties. N is the needle, the poles of
which are bent down and enter the axes of the coils C; o is a shaft upon
which the needle turns; c is a small contact piece fixed on this shaft, which
when the needle is moved by the current vibrates between the stops s and s¹.
The direction of the wires of the coils is so arranged that when one pole of the
needle is solicited downwards the other is driven upwards, and vice versa.
w, w, are small weights, which, in the normal position of the relay, rest upon
a table or support T. When the line current passes the weight on one side
of the turning shaft is lifted, while on the other side a loop allows the needle
to descend, leaving the weight upon the support T. These little weights w, w,
can be arranged by means of notches on the turning shaft or otherwise, either
at an equal distance from o or at unequal distances if any particular force of
current is required to work only in one direction. P, M, is the small perma-
nent magnet fixed on the shaft o, which I use for the purposes of recal; p is
the soft-iron pin which acts on one pole of the magnet P, M, and recals the
contact c against the stop s¹. The force of the recal can be regulated by
screwing the pin further from or nearer to the permanent magnet. When a
current is sent in the right direction the attraction of p will be overcome, and
the contact piece c will be brought against the stop s, which is connected with
one end of the coils of the instrument. The contact piece c is connected with
the positive pole I, P, of the local battery which works the instrument, and
the stop s with one end of the coils of the instrument, the other end of which
is connected with the negative pole I, N, of the same battery.
Figure 25 shews the other form of needle to which I have alluded. N is
the needle; it is suspended on an axis at o, and it will be seen that its two
ends are so bent as to enter into the axes of the coils C, round which the line
current flows when a signal has to be made; and these coils are so arranged
that when a current is sent in one direction both of them tend to draw in the

page_text: ends of the needle, and when sent in the other direction both of them tend to
repel the needle. I have not shewn the other details, as they will be similar
to those shewn in Figure 24.
Another modification of this axial system which I sometimes adopt, and
which is better fitted for needle instruments than those already described, is
shewn in section in Figure 26, in which A is the base board, C two coils
through which the line current passes, and M a permanent magnet which
works in the interior of these coils; N is the indicating needle suspended on
an axis at o, below which it descends, and at o' carries the permanent magnet
M, which is evenly balanced at that point. The coils are arranged to act
together upon the permanent magnet when a current passes through them, so
that when the current is sent in one direction it is drawn to the right, and
when sent in the other direction it is drawn to the left, thereby moving the
needle N to the position shewn by the dotted lines; r is a rod also fixed to the
axis o, to which are attached the weights w, which can be placed at any
distance from the axis o, and which act in the manner already described.
Different forms may be given to these needles without departing from the axial
system, which forms the peculiarity of this part of my Invention.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim as my "Improve-
ments in the Mode of Working Telegraphic Lines, and in Instruments and
Apparatus employed for Telegraphic Purposes,"
First, the method herein-before described with reference to Figure 1 of the
accompanying Drawings by which the evil effects of accidental currents when
signalling by electricity are prevented.
Second, the several arrangements herein-before described and represented
in Figures 2 to 10 inclusive of the accompanying Drawings by which the
retardation of signals which takes places in the arrangements heretofore
employed, especially in submarine lines, is obviated or diminished.
Third, the arrangements herein-before described and represented in Figures
11 and 12 of the accompanying Drawings for carrying on signals step by step,
and for working relays and instruments.
Fourth, the several methods herein-before described and represented in
Figures 13 to 18 inclusive of the accompanying Drawings, by which I am
enabled to work two or more instruments simultaneously with distinct
messages through one line wire; and more especially I claim the system of
compensating electro-magnets shewn in Figures 13 and 14, and the employ-
ment of the qualifying local currents, also described.

page_text: Fifth, the several arrangements of manipulators herein-before described and
represented in Figures 19 to 21A inclusive of the accompanying Drawings for
sending the various currents required to work the different instruments.
And, sixth, the several relays herein-before described with reference to
Figures 22 to 26 inclusive of the accompanying Drawings, and more especially
the axial system represented in Figures 24, 25, and 26, whether applied to
relays or instruments.
In witness whereof, I, the said William Hickling Burnett, have hereunto
set my hand and seal, this Seventeenth day of June, One thousand
eight hundred and sixty-three.