Apparatus for the Employment of Vibratory Electricity in Telegraphy.
Year: 1886

page_text: Date of Application, 17th Dec., 1886
Complete Left, 15th Sept., 1887..
Complete Accepted, 18th Oct., 1887
RESERV
PROVISIONAL SPECIFICATION.
Apparatus for the Employment of Vibratory Electricity in
Telegraphy.
1, CHARLES LANGDON-DAVIES, of 110 Cannon Street in the City of London,
Electrician, do hereby declare the nature of this invention to be as follows:
By the words vibratory electricity I intend to describe exceedingly brief, electrical
impulses or movements such for example as those produced in the secondary of an
induction coil, by the make and break of the primary circuit.
I do not, however, insist that the impulses shall be induced, they may be brief,
direct currents from a battery, they may be all in the same direction, or may be
alternating but I prefer that they shall be those impulses which I find are capable of
being produced in an electro static field, not necessarily including a conducting
circuit and which I have described in a previous Patent dated 11th April 1885,
No. 4506, as Phonoporic impulses.
I include among the means of producing vibratory electricity, all kinds of dynamo-
electric machines, magneto-electric machines, influence machines, induction coils, and
other similar apparatus, and I prefer that when any instrument, except a Phonopore,
is used to produce vibratory electricity, it shall be connected to the line through a
Phonopore or through a condenser, though the latter is not so well suited to the
purpose as a Phonopore.
The transmitter, I prefer, is similar to that described in my Patent No. 4506 in the
year 1885, but with some improvements.
It contains a bobbin in which several insulated wires are wound. Two of these
wires are connected with the main circuit, the other end of each of these two wires
is insulated. There is no circuit through them.
There are other wires in the bobbin and these form a multiple local circuit in which
a battery is included. I use a multiple in preference to a single circuit because it
materially reduces the sparking between the contacts.
Within the bobbin there is a core, and this is magnetised by the local current when
the battery circuit is completed.
A metallic tongue or reed is fixed in proximity to the extremity of the core, and

page_text: this, when it vibrates, makes and breaks the battery circuit and pulsations are produced
in the line.
A finger key starts and arrests the pulsations. When it is put down it does two
things it mechanically jars the reed, and sets up a slight tremour in it, and it also
closes the battery circuit through the reed.
When I desire to use this transmitter for harmonic currents, and for that purpose,
to render the action of the reed as free as possible, I arrange that, when the key is
put down, it will close the battery circuit through a weak slow-acting spring or a
pendulum in contact with the reed.
At this time the reed is not resting upon the stud with which it makes its working
contacts for this would interfere with the complete freedom of vibration of the reed
which it is important to retain.
The first vibration of the reed throws the slow spring or pendulum out of action,
and the reed then makes its own contacts with the stud and continues to vibrate as
iong as the key remains depressed.
a screw.
To facilitate adjustment, 1 provide the core with a movable pole piece attached by
I make the core hollow and arrange that the screw may be reached and
turned by a tool passed through the core from the further end.
To adjust the contact stud, which requires accurate setting, I sometimes employ a
screw with a milled head and a taper projecting end.
The stud is held by a spring against this taper end which acts as a wedge to set it
forward or allow it to retire.
This arrangement is used in the receiving instrument to adjust the tongue towards
the reed pin and is applicable also to effect other fine adjustments.
The platinum wire or other contact piece on the stud is sometimes placed out of the
centre when, therefore, the stud is turned it is brought to bear upon a fresh
surface in the contact plate of the reed which eonsequently requires cleansing loss
frequently.
To further assist this object I arrange a commutator in the primary circuit so that
the direction of the currents may be occasionally changed. This increases the life of
the contacts.
The receiving instrument contains a bobbin surrounding an iron core which I call
the line bobbin.
There are usually two coils in the line bobbin, especially when the receiver is to be
employed for duplex working. The two coils are then so connected that all impulses,
originating at the home station, divide between the two coils and counteract each
other one part going to the line, the other to an artificial or balancing line, herein-
after described.
The impulses arriving from the distant station, on the contrary, operate in the same
sense in cach coil.
The balance line usually contains a resistance and it has this peculiarity; it has no
through circuit but, terminates in one of the wires of a Phonopore, such as is described
in the Specification of my Patent No. 10990 in the year 1884, and the other wire of
the Phonopore has an earth connection.
In order to assist the action of the balance line, I sometimes modify the proportion
of the two wires in the receiver line bobbin as regards each other, so as to form
within the coil an approximate balance. or instead of one bobbin with two wires, I use
two bobbins with one wire each, one being very much smaller than the other; and
connect one end of one of them to the main line and the other to the balance line as
before described.
The line bobbin of the receiving instrument may be connected either in the line
circuit, if there be a circuit, or between the line wire or transmitter already
described, or between the line wire and a separate Phonopore inserted between it and
the earth.
Ordinary telegraph instruments may be placed as shunts to my Phonopore instru-
ments and will not be injuriously affected by them.
The two forms of telegraphs may then be worked simultaneously in the same wire.

page_text: By the use of a balancing line in connection with my receiver 1 prevent the receiver
from being injuriously affected by shocks resulting from the use of the transmitting
key of the ordinary Telegraph.
The impulses received from the further end of the line, as already stated, in passing
through the two coils in the bobbin of the receiver, conspire to vary the magnetism of
the core.
Now in the other end of the same core there is another coil, which I call the
re-inforcing coil, and which is in a local battery circuit, in which is included a relay
of ordinary construction working a printer or a sounder, or other instruments which
translates into visible or audible signs the vibrating signals entering the receiver.
I place a magnetic needle in proximity to the re-inforcing coil or some part of the
core to serve as an indicator.
In some cases the relay may be dispensed with, the signalling instrument such
as the sounder or printer occupying the position which the relay would otherwise
Occupy.
When the signalling instrument is in the reed circuit, or when a large battery is
used therein, it is preferable to make the re-inforcing coil of multiple wire in order to
moderate the spark.
Magnetically connected to the core of the receiver at one end, there is a reed or
stiff steel blade which at its free end is brought into close proximity to the other end
of the core.
The core is made hollow and provided with an adjustable pole piece as already
described.
Any variation in the magnetism of the core, resulting from vibratory impulses from
the other end of the line, sets this reed in motion, and the pin fixed upon it strikes a
metal tongue and causes it also to vibrate.
A spring or pendulum, resting on the tongue completes the local circuit containing
the relay and re-enforcing coil.
The vibration of the tongue opens or impairs the contact and thereby causes the
re-inforcing coil to vary the magnetism of the core in an increased degree which
insures that the contact shall either he completely broken or sufficiently impaired to
permit the armature of the relay to fall back to its contact.
The reed, tongue and pendulum are so arranged as to prevent the injurious effect
upon my receiver from the presence of currents or charges of electricity other than
those I wish to employ for my signals.
For this purpose I place the tongue only so near to the reed as that it will be
struck if the reed is caused to vibrate by impulses coming at such a rate as to support
each other in their action upon the reed, so that a single impulse will not be sufficient
to cause the reed to vibrate with as much amplitude as is necessary to strike it with
the force required to cause it to act upon the pendulum.
The pendulum itself may be a spring, but it is preferable that it should be hung
upon pivots.
Near its lower end a screw projects horizontally upon which a nut is placed. By
moving this nut nearer to or further from the pendulum I can regulate its action.
When the contending currents are very severe I use a dual reed consisting of two
reeds, one of steel or iron associated as described with the core, and set in motion by
variations in the core magnetism; the other of non-magnetic material turned in unison
with the first and placed in close proximity to it.
When the first reed vibrates the second vibrates also although they do not touch,
and I place upon the second reed the pin or other appliance which is required for
actuating the contact between the tongue and pendulum.
These arrangements also assist the duplex action of the receiver, and the balance
line does not require the frequent adjustment which has hitherto been necessary in
duplex telegraphy.
When there are no contending currents to deal with these arrangements are generally
unnecessary and the contact which works the relay circuit may be direct from the
pendulum to the reed.

page_text: When I desire to avoid the use of a separate instrument as a relay I cause my
receiving instrument to act as its own relay by making the following modification
in it.
The reed is not magnetically connected with the core but is preferably itself a
permanent magnet. Upon the end of the core opposite the line bobbins I place an
iron armature which supports an additional pole piece in such a position as that I can
place another bobbin upon it without preventing the adjustment of the opposite pole
piece near the reed. Upon this second pole piece, which I call the relay pole piece,
I place a coil which is inserted with the reinforcing coil, and the object of which is
to concentrate magnetic action upon the relay pole piece. I place near to this pole
piece an armature which, when held up by a charge of magnetism, breaks the local
circuit containing the signalling instrument and which, when released by the discharge
of magnetism consequent on the action of the tongue and pendulum contact, completes
the local circuit and works the signalling instrument. This arrangement is generally
sufficient, but if required there may be two relay pole pieces having coils wound in
opposite directions and arranged so that their nature shall conspire to work the relay
armature in the same direction.
The resistance which I employ in the balance line consists of a trace or film made
upon a metallic surface with plumbago or other suitable conducting material. Contact
with the surface is made by means of a stylus or contact piece composed of the same
plumbago, or other conducting material. This contact piece can be moved along the
surface of the film so that the distance which the current has to pass along the film
or trace from the movable contact to a fixed contact can be varied to give the resistance
required.
By using for the movable contact piece the same material as that with which the
trace or film is made, I cause this trace or film to be constantly replenished and
strengthened whilst the instrument is in use.
The vibratory telegraph is not necessarily combined with an ordinary telegraphic
system. It may be used independently and either single or duplex.
In the former the line wire is connected through a single wire hobbin either to one
wire of a Phonopore the other wire of which is connected to earth, or the bobbin
contains two wires which may be placed in either of the positions previously described,
or the line wire is connected through one wire on the bobbin of the receiver with
one wire of a Phonopore, and the other wire of the Phonopore is connected through
the second coil on the bobbin of the receiver to earth.
The impulses passing in the latter re-inforce those received direct from the line
wire.
The arrangements of tuned reeds and for permitting their freedom of action enable
harmonic instruments to be employed, so that a number of services may take place on
the same wire simultaneously either simplex or duplex with or without ordinary
telegraphs.
In place of free reeds, tuning forks, reeds held at both ends, and tuned strips of
metal may be used under similar conditions, though not always with equal effect.
Dated this 17th day of December 1886.
CARPMAEL & Co.,
Agents for the Applicant.

page_text: Apparatus for the Employment of Vibratory Electricity in
Telegraphy.
I, CHARLES LANGDON-DAVIES of 110 Cannon Street in the City of London
Electrician do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement :-
By the words vibratory electricity I intend to describe a rapid succession of
exceedingly brief electrical impulses, movements or currents such for example as those
produced in the secondary of an induction coil by the make and break of the
primary circuit.
I do not however, insist that the impulses shall be induced, they may be brief direct
currents from a battery, they may be all in the same direction or may be alternating,
but I prefer that they shall be those impulses which I find are capable of being
produced in an electro tonic field not necessarily including a conducting circuit as
hitherto understood, and which I have described in a previous Patent dated
11th April 1885 No. 4506 as phonoporic impulses.
I include among the means of producing vibratory electricity all kinds of dynamo-
electric machines, magneto electric machines, influence machines, induction coils and
other similar apparatus capable of producing extremely brief, minute impulses in rapid
succession, which in consequence of their brevity and rapidity, among other reasons,
are not capable of working ordinary telegraph instruments. I prefer that, when any
instrument, except a phonopore, is used to produce vibratory electricity, it shall be
connected to the line through a phonopore or through a condenser, though the latter
is not so well suited to the purpose as a phonopore.
Figure 1 represents my transmitter. It contains a bobbin A A A A constructed
as follows:-
The core R figure 1 consists of a split tube of soft iron, which may conveniently be
3 inches long and ths of an inch external diameter. It must fit the flanges FF
closely so that it shall not vibrate. To facilitate the adjustment of the front end of
the core towards the reed or tongue TT. I sometimes provide the core with a movable
pole piece (shewn separately in Figure 3) consisting of an iron pin screwed into the
front end of it nearest to TT and operated by the brass rod fixed to the pin running
through the length of the core to an adjusting screw at the back of the instrument;
or the pin may be dispensed with and the whole core made to move, as shown in
figure 1, in which case the core should be stuffed with a rod of vulcanite R¹ R² to
which it may be fixed by two or more pins as indicated at R¹. It is advisable that
these pins should not touch each other or bring two parts of the core into metallic
contact. The vulcanite rod is continued towards and fixed to the adjusting screw CC.
This arrangement permits the whole core to be adjusted towards the reed.

page_text: Upon the core, or as near thereto as may be, I wind the primary coil which serves
to magnetise the core and causes it to act on the reed TT when the circuit is closed
through the battery.
A rapid interruption of the current such as is necessary in these instruments is
accompanied, under ordinary circumstances, by a succession of sparks which damage
or destroy the contacts and thereby throw the instrument out of action in a very short
time. To obviate this I construct the magnetising coil in layers of separate wires
instead of in the ordinary way.
The primary coil of my transmitter is a multiple wire coil, which I construct
as follows:- wind a single layer of insulated wire say 009 of an inch in diameter
and bring out both ends; over this I wind another layer and bring out the ends in the
same way, and so I wind layer after layer separately until I have a sufficient number
of layers, say about 14. Isolder or otherwise connect the free ends of all these layers
at one end of the coil together, and do the same with the wires at the other end of
the coil.
Figure 4 shows schematically the connections of the primary circuit, and figure 1
shows the working parts. ZC is the battery to which is connected one of the
combined ends of the primary coil and the other combined end is connected to the
contact screw S. This contact screw is placed in proximity to the reed or
vibrator TT preferably tuned to a given note or rate of vibration, supported on a
frame which is fixed to and forms part of the lower front, contact K' of the key.
The upper front contact K2 is connected through the middle point of the key or
otherwise to the battery thus completing the primary circuit.
When the key put down it does two things it mechanically jars the reed by
striking on a piece with which it is rigidly connected and so sets up a slight tremor in
it, and it also closes the battery circuit through the reed. This jarring is an advantage
in starting vibrations of the reed and reduces the necessity of pressure between the
reed and contact screw ( S.
Especially when I desire to use this transmitter for harmonic telegraphy Iseck to render
the action of the reed as free as I can, so that it may have as much influence as
possible in governing the rate at which the primary circuit is made and broken.
With this object I arrange that when the key is put down it will close the battery
circuit through a weak slow acting spring or pendulum Q, figure 1, in contact with
the reed.
At this time the reed is not necessarily resting upon the screw or stud CS with
which it makes its working contacts, for this would interfere with the complete freedom
of vibrations of the reed, which it is important to retain.
The first movement the reed throws the slow acting spring Q out of action and the
vibrating reed then makes its own contacts with the studs CS and continues to vibrate
as long as the key remains depressed.
The currents in the primary coil generate the impulses in the secondary phonopore PT
which I construct as follows. Figure 1 shows the working parts and Figure 4 the
connections: Upon the bobbin of the transmitter, over the primary coil, I wind two
insulated wires side by side, No. 36 B. W. G. is a suitable diameter. For the sake of
distinction I will call these wires red and green. The commencement of the red wire
is connected to the line and the commencement of the green wire is insulated, when a
sufficient length of these two wires, say 600 yards is wound side by side upon the coil
the end of the red wire is insulated and the green wire is connected to earth: these
two wires are thus completely insulated from each other.
A modification of this arrangement which I find advantageous under some
circumstances is as follows:
I at first wind the green wire alone, the inner end being connected to the line;
I coil this single wire to a suitable depth, say half an inch and I then commence with
the red wire, the inner end of which I insulate, and I complete the secondary by
winding the green and red wires together side by side for a length of about 500 yards.
The outer end of the green wire is then insulated and the outer end of the red wire
is connected to earth. There is thus no conducting circuit through the secondary.

page_text: To adjust the contact stud CS, which requires accurate setting. I sometimes
employ a screw with a taper or conical projecting end A A Figure 5. The stud CS
is then fitted into a carrier C, and the stud with its carrier is held against the taper end
of the screw by springs. This taper end acts as a wedge to set forward the stud or
allow it to retire. The platinum wire or other contact piece PW on the stud, is
sometimes placed out of the centre, when, therefore, the stud is turned in its carrier
the contact piece is brought to bear upon a fresh surface in the contact plate of the
reed, which consequently requires cleansing, repairing or filing less frequently.
To further assist this object I sometimes arrange a commutator in the primary circuit
so that the direction of the currents may be occasionally changed. This increases the
life of the contacts.
As long as the key is held down, thereby closing the primary circuit, a rapid stream
of short currents flows through the primary coil; the rate at which these currents are
commenced and interrupted is regulated by the vibrations of the reed. The currents
generate in the secondary phonopore rapid electrical impulses of great intensity and
infinitessimal duration and these impulses travel in the line.
When an induction coil is used to generate these impulses the various organs of the
transmitter are constructed in the same way except the secondary phonopore, which is
replaced by a secondary coil connected to earth or to line through a phonopore instead
of by a conducting wire.
Any other apparatus, used to generate the rapid vibratory impulses required, should
also be connected to earth or line through a phonopore.
Figure 2 represents a front elevation of the receiving instrument which translates
the rapid series of electric impulses or vibrations coming from my transmitter or any
of the transmitting instruments herein described of which series of impulses each
signal is composed, into a single current capable of working ordinary telegraph
instruments in a local circuit.
The bobbin LB upon the soft iron core CC I call the line bobbin. There are
usually two coils in the line bobbin especially when the receiver is to be employed for
duplex working, although for simplex working a single coil is generally sufficient.
RC, RC, is the re-inforcing coil, wound on the same core but forming part of a
separate local circuit in which there is a permanent current from a battery, maintaining
a charge of magnetism in the core except when the circuit is distributed by signals as
hereinafter described. This local circuit is shewn schematically in Figure 6. It passes
from the battery through the coil RC to the tongue S¹ which touches the pendulum S,
and, if required, through a relay R of ordinary construction, to the battery: such
relay when employed would include in its own local circuit a printer, sounder or other
instrument with its battery.
In front of the line coil LB figure 2, there is a reed or steel blade B B which reed
is brought into close proximity to the end of the core. The reed may be fixed at both
ends, as in the drawing Figure 2 or it may be free at one end as in Figure 6. The
coro is a split iron tube and may be provided with an adjustable pole piece similar to
that described in the core of the transmitter. It is convenient to place a pin upon
the reed projecting towards the tongue S¹.
Variations in the magnetism of the core resulting from vibratory impulses in the
line coil LB arriving in rapid succession from the line, set the reed in motion and,
when the motion is sufficient, it strikes the metal tongue S¹ disturbing or impairing
its contact with the pendulum S. This disturbance reduces the current in the
coil RC and therefore the magnetism in the core resulting from it. Now this
magnetism was holding the reed in a state of tension towards the core, the reduction
of the magnetism reduces this tension; the result is that the amplitude of the
vibration of the reed is increased and it strikes a blow upon the tongue S¹ which causes
the pendulum S³ to break contact. This contact would however be immediately
renewed if the vibrating organs were at rest; but the impulses in the line bobbin
5 continuing to arrive in rapid succession maintain the tremor in the reed which tremor
is communicated to the tongue and this very effectually because the reed being no
longer drawn towards the core-is pressing upon the tongue the result is that contact

page_text: between the tongue S¹ and pendulum S is not again perfected until the cessation of
the vibratory signal coming from the line permits the reed to be at rest; the instant
that this takes place the reed is drawn away from the tongue towards the core ready
for the next signal. By this means a rapid succession of minute impulses is made to
give a signal of any required length.
The current which magnetises the core also holds up the armature of the local relay
which falls whenever the contact parts S1 and S2 are separated or their contact
paired. This relay thereby works a printer sounder or other telegraph instrument
the local relay circuit.
If the tongue and pendulum are placed out of reach of the reed the vibrations of the
reed will have no effect upon the relay. If they are now brought nearer they may be
so placed that vibrations reaching a certain amplitude shall affect their contact (and
'so work the relay), while other vibrations not attaining the necessary amplitude will have
no effect, and will never bring the reinforcing coil into action.
I so arrange the reed, tongue and pendulum as that contending currents or
impulses, that is to say other impulses than my own, produced in the wire at the same
time as those I wish to employ shall not work my receiving instrument. For this
purpose I place the tongue S¹ only so near the reed B B as that it will not be struck
unless the reed is caused to vibrate by impulses repeated at such a rate as to support
each other in their action upon the reed, and so that a single impulse or a series of
impulses not arriving at the rate required by the natural rate of the reed, will not
cause the reed to vibrate with as much amplitude as is necessary to enable it to strike
the tongue with the force required to cause it to act upon the pendulum.
In order to do this I require a micrometrically fine and very solid adjustment which
1 construct by means of a screw with a tapering or conical end as before described
and shewn in figure 2, MS, MS. The tongue S' is mounted upon a slide which also
curries a support VVVV in which is another slide of vulcanite or other insulating
material, on which the pendulum is mounted, and a similar screw may be provided
therewith, to adjust the pendulum towards the tongue. The slide provided with a
pin which is kept pressed upon the cone by a spring.
I first adjust the pendulum towards the tongue by means of the screw M² or in the
alternative by securing the nut N on the pendulum, nearer to or farther away from the
end I then adjust the whole by means of the screw MS at the exact distance from
the reed which will permit it to work the receiver only when the proper signals arrive.
As an additional means of accomplishing this object and when the contending
currents are very severe I use a dual reed, as shewn in figure 7. It consists of two
reeds, one II of steel or iron, the other TT of non-magnetic material. The two reeds
are tuned in unison and placed in close proximity to each other. The steel or iron
reed being close to the core and acted upon by the variations in its magnetism. These
variations have no effect on the non-magnetic reed, but if this steel or iron reed
vibrates at the proper rate of the non-magnetic reed, the non-magnetic reed will
vibrate also. Contending currents, will affect the steel or iron reed but cannot affect
the non-magnetic reed or tongue S¹. Only when the magnetic reed is vibrated at its
proper
rate can it cause the non-magnetic reed to vibrate, and then the non-magnetic
reed sets the tongue in action.
These arrangements also assist the duplex action of the receiver and the balance
line does not require the frequent adjustment which has hitherto been necessary in
duplex telegraphy, because the rate of vibration of the local transmitter not being the
same as the rate of vibration of the local receiver, it has less tendency to actuate the
local receiver and the outgoing impulses from the transmitter are to some extent in
the nature of contending currents towards the receiver attached to it.
When there are no contending currents to deal with these arrangements are generally
unnecessary and the contact which works the relay circuit may be direct from the
pendulum to the reed.
When I desire to avoid the use of a separate instrument as a relay I cause my
receiving instrument to act as its own relay by making the following modifications in
it, and I then call it a transformer.

page_text: Upon the end of the core opposite the line bobbin or bobbins I place an iron
armature which supports an additional polo piece upon which I place another bobbin C³
figure 2, and I am still able to adjust the front pole piece with respect to the reed, as
before described. Upon the relay pole piece I place the coil which is in circuit
with the reinforcing coil and the object of which is to concentrate magnetic action
upon the relay pole piece. I place near to this pole piece an iron armature which,
when held up by a charge of magnetism, breaks the local circuit containing the
signalling instrument and which when released by the discharge of magnetism
consequent on the action of the tongue and pendulum contact completes the local
circuit and works the signalling instrument.
This arrangement is generally sufficient, but if required there may be two relay
pole pieces having cores wound in opposite direction and arranged so that their
action shall conspire to work the relay armature in the same direction, or by
dispensing with the adjustment of the front pole piece towards the reed, I can
dispense altogether with the relay pole piece and its coil and use the core of the
receiver acted upon by the reinforcing coil to actuate the relay armature which is
thus placed at the end of the core opposite to the reed. A back stop is provided to
prevent the armature from striking the core, as that might cause the reed to vibrate.
It is advisable to construct the iron parts comprising the relay of solid iron and
somewhat heavy so that the action of the relay may be sluggish as compared with
that of the tongue and pendulum contact.
By this means the vibrations entering the instrument are transformed into the
visible or audible signals used in ordinary telegraphy.
In some cases the relay may be dispensed with altogether and the signalling
instrument such as a sounder or printer put in circuit with the reinforcing coil in the
position which the relay would have occupied or placed near the core to be worked
by the magnetism in the core resulting from the action of the reinforcing coil.
When the signalling instrument is in circuit with the reinforcing coil or when a
very large battery current is employed therein I make the reinforcing coil of
multiple wire in layers as previously described to moderate the spark at the
contacts.
In duplex working I wind two coils in the line bobbin LB (figure 2) and I so
connect them that all impulses originating at the home station divide between the
two coils and counteract each other; one part going to the line, the other to an
artificial or balancing line, hereinafter described. The impulses arriving from the
distant station, on the contrary, operate in the same sense in each coil.
This arrangement is indicated in figure 9. The impulses from the transmitter PT
divido in the line bobbin L B, LB', and counteract the effect of each other on the
core but flow in the same direction in the coils of L B², LB where they conspire
with each other to affect the core.
The balance line BL usually contains a resistance and it has this peculiarity; it
has no through circuit, but terminates in one of the wires of a phonopore BP,
composed of two insulated wires each say about 500 yards in length laid side by side
throughout their whole length, upon a bobbin or other convenient receptacle. One
end of the first of these wires is connected with the balance line and the other end
insulated; and one end of the second of these wires is connected to the earth and its
other end insulated.
I proportion the two wires in the receiver line bobbin as regards each other so as
to form within the coil an approximate balance or instead of one bobbin with two
wires, I use two bobbins with one wire each, one being very much smaller than the
other, and connect one end of one of them to the main line and the other to the
balance line as before described. Or instead of winding two wires side by side as is
usual in duplex coils I wind one over the other producing in effect a single wire coil
with an exterior connection to some point intermediate between the two ends, as well
as connections at the ends. Figure 12 shews such a coil; I is the intermediate
connection, BL the balance line and L the line. Impulses from a local transmitter
enter the coil at I and divide neutralising each other in their effect on the core. I

page_text: prefer to arrange the proportions of the coil so as to put the greater part of its
resistance in the balance line, and but little in the main line. A few layers of the wire
wound nearer the core are sufficient to counteract the effect of a larger number of
those farther from it, I therefore prefer to connect the balance line to the outer end
and the main line to the inner end of the coil.
My balance line being insulated is not subject to the same loss of current as an
ordinary balance line.
The resistance which I employ in the balance line is a rheostat consisting of a trace
or film made upon a non-metallic surface with plumbago or other suitable conducting
material. The trace may be made upon the edge or side of a strip of vulcanite and
tne contact piece is arranged to move along the trace of plumbago by means of a
screw or other similar contrivance. In this way the distance which the current has
to pass along the film or trace from the moveable contact to the fixed contact is varied
so as to give the resistance required. In order to prevent the movable contact from
wearing out the trace or film I construct the contact piece of the same plumbago or
other material of which the filin itself is composed, and thus constantly replenish and
maintain the film whilst the instrument is in use.
Figure 13 shows this rheostat. PC is the plumbago carrier: the trace or
film. The arrows indicate the course of the impulses or current, and the amount of
resistance interposed is regulated by the handle. When a longer film is required it
can be supported upon the worm of a screw instead of a straight edge. A film of
lower resistance is made by increasing the surface coated.
My method of duplexing the vibratory telegraphs does not require so accurate a
balance as is necessary in ordinary duplex telegraphy, and the incessant adjustment
of the balance line is unnecessary. My arrangements for preventing the action of
contending currents, and the approximate balance in my duplex coil assist the object
which can almost always be completely attained by means of the rheostat described.
Which rheostat however may be replaced by ordinary resistance coils. Considerable
variations in the resistance of the main line may take place without disturbing the
independent action of my duplex instruments.
The use of the balance line and the arrangements associated therewith in connection
with my receiver also prevent injurious action upon my instruments from the shocks
resulting from the use of the transmitter key of an adjacent ordinary telegraph, and
other similar contending impulses.
The receiving instrument may havo two line bobbins the core or cores of which
combine to act on the same reed, and it may have two re-inforcing coils, and all
these coils may be mounted on a single core of horse shoe or similar shape, or on two
cores whose ends, where the re-inforcing coils are, combine in their action on the
same relay armature. The line coil may be a phonopore.
When I do not desire to work a relay or ordinary telegraph instrument I omit
those parts of the receiver which relate thereto, and construct it only of the line
bobbin LB, re-inforcing coil RC and the tongue and pendulum arranged to press
upon the reed. The sound of the vibrations of the reed is then sufficient to give the
signals. Or my transmitting instrument may if desired be advantageously used in
combination with a simple sounder constructed substantially like a receiving
telephone with a coil upon the end of a magnet or electro magnet and an armature to
vibrate, the said armature being either a plate of iron or steel or else a
piece of iron
or steel mounted upon a spring, disc, plate or membrane of some elastic vibrating
resonant non metallic substance such as wood, celluloid, parchment etc. The
arrangements for duplexing are also available in this case.
The line bobbin of the receiving instrument may be connected either in the line
circuit, if there be a circuit, as shewn in Figure 11 at LB, or between the line
circuit and transmitter, as shewn at L B, Figure 11, or between the line wire and a
separate phonopore inserted between it and the earth.
Figures 4 and 10 show the connections of the transmitter and the line bobbin of
the receiver as regards the line in simplex working; in this case the line bobbin LB
is connected to the earth by a separate phonopore P, and to the line through an

page_text: insulated screw K³ forming the upper back contact of the transmitter key and which
is shown in Figure 1; when the key is depressed for sending, the receiver is
disconnected from the line, when the key is at rest the receiver is connected to the
line through the screw, ready to receive the signals from the distant station.
When the line bobbin forms part of the line circuit, a cut out is provided at the
back of the key, so that when the key is depressed in sending, the line bobbin is cut
out as indicated schematically at K in Figures 8 and 11.
In duplex working one of the coils of the line bobbin is inserted in the line and the
other in the balance line, and is connected with the secondary phonopore of the
transmitter directly as shown in Figure 9 L B and L B².
Ordinary telegraph instruments may be placed as
instruments and will not be injuriously affected by them.
shunts to my vibratory
The position of these shunts is shewn in Figures 9 and 10 by dotted lines and also
in Figure 11. OT is the ordinary telegraph. The shunt may include both the
transmitter and the line bobbin of the receiver, or only the transmitter, or in the case
of duplex working, one coil of the line bobbin LB Figure 9, or both coils as at L B²
Figure 9. The connection of the ordinary telegraph to earth need not be at the same
place as the earth connection of the vibratory telegraph.
wire.
The two forms of telegraphs may then be worked simultaneously on the same
The vibratory telegraph is not necessarily combined with an ordinary telegraph
system. It may be used with considerable advantage as an, independent system:
when this is done it is worked with advantage on a line having no conducting circuit
as is shewn in Figure 8 where PT is the transmitter and LB the line bobbin of the
receiver or transformer. By omitting the dotted lines OT in Figures 9 and 10 other
methods of open circuit working are shewn, both simplex and duplex. In the
simplex the line wire is connected through a single wire line bobbin to one wire of a
phonopore, which may be the transmitter, the other wire of which is connected to
earth in the duplex a double coil is necessary for the line bobbin, having any of
the forms previously described, and also the other parts of the balance line.
When the transmitter is an ordinary induction coil or other instrument having a
conducting circuit through it, it may be placed in the line which may then become a
conducting circuit, though not to advantage. The modes of connecting the receiving
instrument would be the same as in the case of my transmitter.
A two wire line bobbin may on the open circuit be connected as shown in Figure 14
where the line wire is connected through one wire of the line bobbin to one wire of
the phonopore, and the other wire of the phonopore is connected through the second
wire of the line bobbin to earth. The impulses passing in the earth wire re-inforce
those in the line wire. The arrangements for dealing with contending currents may
be dispensed with on the open circuit.
The arrangements of tuned reeds, and for permitting their freedom of action enable
harmonic instruments to be employed, so that a number of instruments governed by
different notes, may be worked simultaneously on one wire; any or all of these
services may be worked either simplex or duplex and either with or without ordinary
telegraphs working at the same time on the same wire.
In place of free reeds, tuning forks, reeds held at both ends, tuned strips of metal
and other means of regulating the rate of the vibrations may be employed under
similar conditions though not always with equal effect.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :-
1. The transmitter substantially as described consisting of a bobbin with numerous
primary windings whereby sparking is suppressed and with secondary windings
connected with the line each by one and only and with a tongue and with a core
adjustable to vary its attraction on the tongue and with a contact point adjustable in
relation to the tongue and with a key opening and closing contacts as herein
set forth.

page_text: 2. The transmitter substantially as described with primary windings and secondary
windings, and with a core and with a tongue attracted by the core and with a key
striking on a part to which the tongue is attached and thereby serving to set the
tongue in motion mechanically as herein set forth.
3. In a transmitter substantially as described the pendulous contact Q completing
the primary circuit through the tongue when at rest and rendering the instrument at
starting independent of any contact of the tongue with the stud through which the
tongue afterwards periodically closes the primary circuit as herein set forth.
4. In a transmitter substantially as described the method of adjusting the contact
point by the aid of a conical plug with a screw thread upon it as shown in
Figure 5.
5. In a transmitter substantially as described the contact point mounted eccentrically
npon a plug capable of being turned in its holder whereby the duration of the contact
is increased as herein set forth.
6. The receiver substantially as described consisting of a core with a line bobbin
and a reinforcing coil upon it the latter in a local battery circuit closed through
contact parts SS' and of a reed which when set in motion by suitable periodic
impulses in the line bobbin strikes the contact parts S1 S2 and keeping them in
motion opens the local circuit as herein set forth.
7. In a receiver substantially as described the contact parts S1 S2 adjustable in
relation the one to the other and adjustable together in relation to the reed so that
the reed may not act on the contacts to open the circuit of the reinforcing coil until
its vibrations attain a certain amplitude as herein set forth.
8. In a receiver substantially as described the method of adjustment of the contact
parts S1 S2 by means of conical plugs with screw threads thereon as herein
set forth.
9. In a receiver substantially as described the dual reed as herein set forth.
10. The combined receiver and relay substantially as described.
11. In a receiver substantially as described the double or divided line coil upon
the core which adapts the instrument for duplex working as herein set forth.
12. The combination substantially as described for duplex working with vibratory
electricity consisting of the transmitter of the vibratory impulses, the receiver of the
said impulses which opening and closing a battery circuit translates the vibratory
impulses into ordinary telegraph signals and the balancing line with open circuit as
herein set forth.
13. The adjustable resistance or rheostat substantially as described forming part of
a balancing line and consisting of a line or trace of plumbago or like material and a
stylus of the same material which as it is traversed along the trace by suitable
mechanism in connection with it continually renews the trace as herein set forth.
Dated this 15th day of September 1887.
CARPMAEL & Co.,
Agents for the Applicant.