IMPROVEMENTS IN ELECTRIC TELEGRAPH APPARATUS
Year: 1873

page_text: LETTERS PATENT to Joseph Barker Stearns, of Boston, Massachusetts,
United States of America, now of No. 8, Southampton Buildings,
London, Electrician, for the Invention of "IMPROVEMENTS IN ELECTRIC
TELEGRAPH APPARATUS."
Sealed the 22nd May 1874, and dated the 27th November 1873.
PROVISIONAL SPECIFICATION left by the said Joseph Barker Stearns
"
at the Office of the Commissioners of Patents, with his Petition, on
the 27th November 1873.
I, JOSEPH BARKER STEARNS, of Boston, Massachusetts, United States
of America, now of No. 8, Southampton Buildings, London, Electrician,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN ELECTRIC TELEGRAPH APPARATUS," to be follows:-
-
My present Invention relates to further improvements in the apparatus
described in the Specification of former Letters Patent granted to me
the 11th day of November, A.D. 1872, No. 3344, and in the Provisional

page_text: Specification filed with my application for Letters Patent the 1st day of
September, A.D. 1873, No. 2870.
According to one part of my present Invention I provide for the use
of a condenser of less capacity than the cable as follows:--I charge the
condenser by a special battery of greater electro-motive force than
the one used for signaling, using for that purpose a two-point key.
Induction coils may be substituted for the condensers, still using the
two-point key and the two batteries of unequal electro-motive force.
When a condenser is employed it may with advantage in some cases
be made in the form of a submarine cable. A piece of ordinary sub-
marine cable may be used for the purpose, but a special form of cable so
constructed that its resistance and static capacity are very great is
preferable. Such a cable may be made by using a metal of low con-
ductivity, either in the form of fine wire or of thin ribbon, for the
conductor or the inner plate of the condenser; and this ribbon may be
wound spirally around a thick cord in order to obtain great length and
surface of the conductor; this conductor may be covered with a coating
as thin as possible of some dielectric possessing great specific inductive
capacity. A cable may thus be made having a resistance and capacity
many times greater than ordinary submarine cables, and this cable may,
by means of the two-point key and special battery, be charged to a
tension many times greater than the cable through which the signals
are sent by the weaker, battery; and thus one mile of this kind of cable.
will be equal in absolute inductive effect to a hundred miles or more of
the signaling cable.
Instead of a condenser a mechanical, hydraulic, or pneumatic sub-
stitute may be employed to "offset" or neutralize the effect of the static
charge returned from the line or cable; for example, a spring finger or
cam may be made to press against the tongue of the relay or other
moveable part of the receiving instrument at the proper time and with
the proper amount of force to exactly balance the effect of the static
charge. This purpose may be effected directly by the movements of the
key, or indirectly by means of a separate and intermediate piece of
mechanism. Or a current or column of air may, directly or indirectly,
by the movements of the key, be made to press or impinge upon the
moveable part of the receiving instrument at the proper time and with
the requisite degree of force to balance the static charge. Or a column

page_text: as to act in a like manner.
The static balance or compensation may, if desired, be effected
independently of the magnetic compensation, and thus a condenser of
small capacity or other compensating agency may be made to compensate
a large cable capacity. This object may be accomplished in a variety of
ways; for example, one wire of a differential receiving instrument may
be made the "bridge wire" of a duplex bridge, and employed for
receiving the signals, while the static compensation may be effected by
charging and discharging a condenser, induction coil, secondary battery,
or current of short duration through the other wire of the differential
instrument by means of the two-point key and separate battery. Or the
receiving instrument may be wound with three wires, two of them being
used as in ordinary duplex working, and the static compensation being.
effected by charging and discharging a condenser, induction coil,
secondary battery, a current of short duration through the third wire
by means of the two-point key.
Instead of a third wire wound with the two ordinary wires of the
differential instrument and forming a component part of the same, a
separate wire or a separate coil, magnet, or other compensating means
may be employed without affecting the principle of my Invention. The
effect of the static charge and discharge upon the receiving instrument
may also be compensated by the action of a magnet, the position of
which in relation to the tongue of the relay or moveable part of the
receiving instrument is determined by the movements and position of
the key or transmitting apparatus; this magnet may be either a per-
manent magnet, an electro-magnet, or a combination of the two, similar
to that used in the instrument commonly known as "the Hughes' type-
printer." I prefer however the ordinary electro-magnet whose cores are
free to move independently of the other parts, for in addition to the
check put upon the movements of the moveable part of the receiving
instrument by changing the position of the magnet, the force of the
magnetism which is the compensating agent is more easily varied, or can
if desired be altogether suspended in certain positions of the key. For
example, let it be supposed that the receiving instrument is that known
as the "single needle," and that in proximity to the north end of the
needle is placed the south pole of the compensating magnet and vice
versa, if now a current be sent with the line or cable, the north end of

page_text: the needle will have a tendency to move for an instant say to the left, if
however the south pole of the compensating magnet at the same instant
be moved sharply to the right for an instant (but not for the whole time
the key is closed) it will give the north end of the needle a tendency to
move to the right, and consequently no movement of the needle will
take place. Upon opening the key the movement of the magnet is
repeated except that it moves to the left in order to check the tendency
of the needle, which in this instance is to the right. If the magnet is an
electro-magnet its force when in its position of rest may be at its
minimum or nil, and may be so varied by the use of shunts or other well
known means during the movements of the key, as to neutralize the
effect of the static charge upon the needle more effectually at all times
during the charge and discharge. This method of preventing the effects
of the static charge upon the needle by the movements alone or the
movements and force combined of a magnet can be applied to other
form of receiving instrument. The compensation may also be effected
by the action of a magneto-electric current, induced by the movements
of magnet inside of or in proximity to a coil of wire or another
C
any

page_text: When working a cable on the duplex system either by means of
"reversals," or when the dots are made by a current of one polarity and
the dashes by a current of the contrary polarity, this apparent difference
of resistance of the cable becomes a serious obstacle. To obviate this
difficulty I use two rheostats or artificial resistances, one for the positive
current and the other for the negative current, so arranging the two
keys which send the different currents that each shall determine the
use of its own appropriate rheostat. Or one rheostat may be employed
and adjusted to equal the greater resistance (5,000 ohms) encountered by
the positive current, and the positive key may when at rest be made to
"cut out" or "short circuit" a portion (1,000 ohms) of the resistance of
the rheostat, so that when the negative key is used the negative current
will encounter only the smaller resistance (4,000 ohms).
In working long sub-marine cables the current from the signaling
battery is not usually sent directly into the cable, but into one set of the
plates of a condenser, the other set of plates being connected to the
cable. At the receiving end the cable is in like manner conected to one
set of plates of a condenser, the other set of which is connected to one
terminal of the receiving instrument, while from the other terminal of
the instrument a wire extends to the earth. Thus the cable is never in
direct ommunication either with the battery or the carth. In applying
the duplex system to this mode of working cables, it is only necessary
to make the branch or compensating circuit resemble in all respects the
cable as above described, using a differential instrument, or if an ordinary
receiving instrument is used, placing it in the "bridge wire" of a
Wheatstone bridge.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Barker Stearns in the Great Seal Patent |
Office on the 27th May 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
BARKER STEARNS, of Boston, Massachusetts, United States of America,
now of No. 8, Southampton Buildings, London, Electrician, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of November,

page_text: in the year of our Lord One thousand eight hundred and seventy-
three, in the thirty-seventh year of Her reign, did, for Herself, Her
heirs and successors, give and grant unto me, the said Joseph Barker
Stearns, Her special licence that I, the said Joseph Barker Stearns,
my executors, administrators, and assigns, or such others as I, the
said Joseph Barker Stearns, my executors, administrators, 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,
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 ELECTRIC TELEGRAPH
APPARATUS," upon the condition (amongst others) that I, the said Joseph
Barker Stearns, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should parti-
cularly 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 Joseph Barker Stearns, 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, reference being had to the accompanying
Drawing forming a part of this Specification:-
My present invention relates to further improvements in the apparatus
described in the Specifications of former Letters Patent granted to me on
the 11th day of November, A.D. 1872, No. 3344, and on the 1st
September A.D. 1873, No. 2870.
According to one part of my Invention I. provide for the use of a
condenser of less capacity than the line or cable, as follows:-I charge
the condenser by a special battery of greater electro-motive force than
the one used for signalling through the line or cable, using for that
purpose a two-point key, as shown in Figure 1; this key has a stop i
which is insulated from the said key. When the key K is closed the
current from battery B¹ flows through lever and wire p through the
helix and around the core of the receiving instrument o and thence to
the line L, at the same time a current from battery B flows through the
stop i, lever 1, and wire y around the core o, in a contrary direction to.

page_text: and through the rheostat R, h, and to the earth at E. The battery B³
is stronger than the battery B¹, but the currents from the two batteries
are brought to the same strength by making the resistance of R, h;
greater than that of the line or cable L, and the condenser C takes a
higher charge than L because of the greater electro-motive force of B
and the greater resistance of R, h.
A condenser may with advantage in some cases be made in the form
of a submarine cable. An ordinary submarine cable may be used for
this purpose, but a special form of cable so constructed that its
resistance and static capacity are very great is preferable. Such a cable
may be made by using a metal of high specific resistance either in the
form of fine wire or thin ribbon for the conductor, this wire or ribbon
may be wound spirally around a thick cord in order to obtain a greater
length and surface of the conductor, and the said conductor may be
covered with a coating as thin as possible of some dielectric possessing
great inductive capacity. A cable may thus be made having a
resistance and capacity many times greater than an ordinary submarine
cable; this special or condenser cable may by means of the two-point key
K,, and, and special battery B², as shown in Figure 2, be charged
to a tension many times greater than the line or cable through which'
the signals arc sent by the weaker battery B¹, and thus one mile of this
special condenser cable C+C will be equal in absolute inductive effect
to a hundred miles or more of the signaling or ordinary cable. The
rheostat R, h, may in this case be dispensed with, or its resistance may
be made very great to represent the greater leakage of the longer cable.
Instead of a condenser a mechanical hydraulic, pneumatic, or other'
substitute may be employed when so arranged as to produce a pressure
against the movable part of the receiving instrument at the proper
moment, and with the requisite degree of force to balance the effect of
the static charge sent into or returned from the line or cable. For
example, a spring finger or cam a², Figure 3, may be made to press
against the tongue or armature a¹ of the relay at the moment when the
charge is flowing into or returning from the line or cable, and by the
addition of the tension of spring & to that of 2 balance the effect of
charge or discharge upon the tongue or armature of the relay. This
pressure may be applied directly by the movements of the key, or when
more convenient an intermediate piece of mechanism or apparatus may
be employed such as an electro-magnet; a column of liquid or of air

page_text: confined in a tube, or a jet of some liquid or of air may be made to
impinge upon the movable part of the instrument at the right moment;
but in all of these modifications of the said apparatus the principle is
the same, namely, that of applying pressure to the armature or movable
part of the receiving instrument to prevent its movement from the effect
of the static charge and discharge.
J
68 com-
The static balance may if desired be effected independently of the
magnetic or permanent balance, and thus a condenser or other
pensator" of small capacity may be made to compensate a large line or
cable capacity. This may be accomplished in a variety of ways; for
example, one wire t, Figure 4, of a differential receiving instrument may
be made the bridge wire of a duplex bridge, and employed for receiving
the signals in the manner described in the Specification of my former
Letters Patent, No. 3344, A.D. 1872, while the static compensation may
be effected by charging and discharging a condénser or other com-
pensator C through the other wire r of the differential instrument by
means of the two point key K, P, and special battery B³; or the
receiving instrument may be wound with three wires, two of them p
and y, Figure 5, being connected and used as described in my said former
Specifications, and the static compensation effected by charging and
discharging the compensator through the third wire by means of the
two point key K, lever ", and battery B*.
Instead of a third wire wound with the two ordinary wires of the
differential instrument and forming a component part of the same a
separate coil or an electro-magnet may be employed; for example,
the permanent balance may be effected with the differential clectro-
magnet and rheostat in the ordinary manner, while the static balance
may be obtained by allowing the current from the signaling battery or
a special battery to pass through a separate electro-magnet into the con-
denser or compensator.
Figure 6 shows the arrangement of apparatus and connections when
a special battery is employed. When the key K is closed the current
from battery B² flows through the extra clectro-magnet o² and into the
condenser C, but only for an instant while the condenser is receiving
its charge. When the said key is again opened the charge passes back
through o to the earth at E. The extra magnet o² may be placed at a
greater or less distance from the armature h, and thus its compensating
effect upon h may be varied as desired.

page_text: Figure 14 shows the arrangement when the current from the signalling
battery is sent through the extra electro-magnet 03. 0³ may with
08
advantage be made larger than o¹, in which case a compensator of
smaller capacity than the line or cable may be used..
The effect of the static charge and discharge upon the receiving
instrument may also be compensated by the action of a magnet whose
position in relation to the movable part of the receiving instrument is
determined by the movements and position of the key or other movable
portion of the transmitting apparatus. This magnet or compensator
may be either a permanent magnet, an electro-magnet, or an electro-
permanent magnet similar to that used in the instrument commonly
known as the "Hughes' type-printer." I prefer however an ordinary
electro-magnet the cores of which are free to move independently of the
other parts, for in addition to the check exerted upon the movements of
the movable part of the receiving instrument by changing the position
of the compensator, the force of the said compensator may be increased,
diminished, or entirely suspended in certain positions of the key. For
example let it be supposed that the receiving instrument is that known
as the "single needle" the helices of which are wound differentially,
and that in proximity to the north end of the needle is placed the south
pole of the compensator, and vice versa. If now a current is sent into
the line the north end of the needle will have a tendency to move for an
instant, that is to say, while the line is taking static charge say to the
left; if however the south end of the compensator is at the same time
moved sharply to the right for an instant, but not for the whole time
during which the key is closed, it will give the needle a tendency to
move to the right but will in reality only prevent its movement to the
left, and consequently no movement of the needle will take place.
When the key is again opened the movement of the compensator is
repeated, except that in this instance it moves to the left in order to
prevent the movement of the needle to the right. If the compensator
is an electro-magnet its force when in its position of rest may be at its
minimum, and may be so varied by the use of shunts or other well
known devices during the movements of the key as to neutralize the
effect of the static charge and discharge at all times.
Figure 12 shows the needle and compensator thus arranged and also
a device for moving the south end of the compensator for an instant to
the right when the key is making its closing movements, and to the left

page_text: when making its opening movement; but in this Figure in order to
simplify the Drawing I have not shown the helices or the electrical
connections.
Figure 13 is a side view of the needle compensator and helices and
also the electrical connections, but does not shew the mechanism for
moving the compensator.
K, Figure 12, is the ordinary duplex key which need not be herein
further described. % is a short bar or rocker excentrically pivoted at g
so that its extremity. u moves through a considerably greater arc than
its other extremity which follows the movements of the key K to
which it is attached by a pin and slot. When the key K is closed the
extremity of the bar k moves downward and passes the projection v on
the compensator M, but in doing so moves the south pole of the com-
pensator to the right for an instant. When the key is again opened the
process is reversed, the south pole of the compensator moving for an
instant to the left.
D, Figure 13, is a differential helix surrounding the needle N; A is a
helix surrounding the compensator M; B³ is a battery the current of
which produces polarity in the compensator M; R, ², is a rheostat for
regulating the force of the current from B³ and its effect upon M. The
mechanism for moving the compensator is omitted in this Figure.
When the key K is closed the current from battery B flows through the
two wires of the helix D in the usual manner, thus producing the
magnetic or permanent balance. At the same time the south pole of
the compensator M moves sharply to the right for an instant as already
described in order to prevent the movement of the needle N to the left
in consequence of the line taking static charge at that moment.
When the key is again opened the south pole of M moves for a
moment to the left to prevent the movement of the needle to the right
in consequence of the static discharge from the line. This method of
preventing the effect of the static charge and discharge upon the needle
by the movements or the force, or the combined movements and force
of a compensating magnet may be applied to any form receiving
instrument polarized or non-polarized, the single needle instrument
being herein specified merely by way of illustration.
The static compensation may also be effected by a magneto-electric
current generated by the movements of a magnet inside of or in

page_text: proximity to a helix of wire or another magnet, or by charging and
discharging one helix in proximity to another. This may be accom-
plished in a great variety of ways.
In Figure 7 o is a differential electro-magnet, one wire t of which
forms the bridge wire of a duplex bridge. The other wire x being
connected to the terminals of the helix m¹ surrounding an iron core c;
m² is a magnet which is presented to and removed from the core c by the
movements of the key K. When m² is presented to c a momentary
current is generated in helix m² and wire x, and this current acts upon
the instrument o. When m³ is removed from the core ca current of
the opposite polarity is generated which in turn acts upon the instru-
ment o.
In Figure 8 the helix m¹ is connected as before, but is surrounded by
another helix m³ which is charged and discharged by the movements of
the two-point key K in connection with the special battery B³. When
the key is closed a current from B2 flows through m³, and thereby
induces a momentary current in m². When K is opened a current of
the opposite polarity is generated in m¹, and each of these currents in
turn acts upon the instrument o to neutralize the effect of the static
charge and discharge.
Any of the aforesaid described devices for compensating the effect of
the static charge or for producing the static balance may also be applied
to produce the magnetic or permanent balance; by making the pressure
against the movable part of the receiving instrument continue during
the whole time, the current flows to the line instead of making it
momentary as above described, and thus obviating the necessity of
employing the branch or compensating circuit described in the Specifi-
cation of my said former Letters Patent No. 3344, A.D. 1872. For
example, the whole current from battery B, Figure 9, flows through the
receiving instrument to the line; the movement of the key K at the
same time brings a pressure upon the spring & attached to the armature
post d just sufficiently to prevent the movement of the armature / under
the influence of this outgoing current, at the same time leaving the
armature free to move by the addition of the incoming current. When
the key is not closed the ordinary spring s¹ alone acts upon the armature
and is adjusted to the strength of the incoming current. This method
of working is adapted to a polarized or a non-polarized receiving instru-
ment.

page_text: Figure 10 shows a modification of this method of working in which a
separate or extra electro-magnet is employed to produce the static
balance, the permanent balance being effected as described in connection
with Figure 9. In closing the key K a portion of the current from
battery B flows through the extra clectro-magnet o' into the condenser C
until it has taken its charge, after which the whole current flows to the
line. On opening the key the condenser is discharged through the
extra magnet o neutralizing the effect of the discharge from the line
upon the armature.
method of working in
When the key K is
Figure 11 shows another modification of this
which a differential electro-magnet is employed.
closed the current from the battery B flows through the wire p of the
said differential electro-magnet to the line, and through the wire y into
the condenser C as described with reference to Figure 10, the move-
ment of the armature being prevented by the extra spring as in the
arrangement illustrated in Figure 9.
.
It sometimes happens in consequence of the existence of earth
currents that the apparant resistance of a line or cable varies with the
polarity of the battery employed for signalling or for measuring. For
example, the cable as measured by a positive current may show a
resistence of 5,000 ohms, while with the negative current it shows a
resistence of only 4,000.
When working a cable with the duplex system, either by means of
"reversals” or when the dots are made by a current of one polarity and
he dashes by a current of the contrary polarity, this apparent difference
of resistance of the cable becomes a serious obstacle. To obviate this
difficulty I use two rheostats or artificial resistances, one for the positive
current and the other for the negative current, the said rheostats being
so arranged that cach of the two keys which send the different currents
shall determine the use of its own appropriate rheostat. Or one rheostat
may be employed and adjusted to equal the greater resistance (5,000
ohms) encountered by the positive current, and the positve key may
when at rest be made to cut out" or "short circuit " a portion (1,000
ohms) of this resistence of the rhcostat, so that when the negative key
is used the negative current will encounter only the smaller resistance
(4000 ohms).
σε
Figure 15 shows one manner of accomplishing the object of this

page_text: key B, the positive battery; B',.the negative battery; s, a spring
carried by but insulated from K²; p, a point upon which spring s rests
when K² is in its position of repose, thereby "cutting out" section a of
the rheostat R, h. If now the positive key K³ is closed the "cut out"
8, p, is opened and the positive current flows through the whole
resistence of the rheostat (5000 ohms), but if the negative key K' is
closed the "cut out" remains closed, and the negative current flows'
through it, encountering the resistance (4000 ohms) due to sections b, c,
d, e, of the rheostat only.
In working long sub-marine cables the current from the signalling
battery is not usually sent directly into the cable, but into one set of
the plates of a condenser, the other set of plates being connected to the
cable. At the receiving end the cable is in like manner connected to
one set of plates of a condenser, the other set of which is connected
to one terminal of the receiving instrument, while from the other
terminal of the instrument a wire extends to the earth. Thus the
cable is never in direct communication either with the battery or the
earth. In applying the duplex system to this mode of working cables,
it is only necessary to make the branch or compensating circuit
resemble in all respects the cable as above described.
Figure 16 shews the ordinary method of working cables by means of
condensers, and is too well known to need further description; K, is
one of the signalling keys; B, one of the batteries; C¹, the condenser
at the sending end; C2, the condenser at the receiving end of the cable;
L is the cable; and I, the receiving instrument.
Figure 17 illustrates one manner of applying the duplex system to
this method of working cables. The transmitting apparatus is the same
as that shown in Figure 15; o is the receiving instrument; R, h, a
rheostat constituting the branch or compensating circuit; C2, C3, C³,.
are condensers for producing the static balance; ², 2, 3, resistances for
regulating the time of the charge and discharge of the condensers. The
rheostat R, h, and the resistances 71, 72, 73, are so adjusted that the
amount of charge taken by the condensers and also the time required
for charging and discharging the condensers is equal to that of the cable
itself. The instruments and connections are the same at both ends of the
cable, and the transmission of signals, reading, and other operations,
are performed in the same manner as in ordinary cable. working..

page_text: Figure 18 shows a modification of this part of my Invention in which
the "bridge" is substituted for the differentially wound receiving
instrument, but in other respects the apparatus shown in this Figure is
the same as that shown in Figure 17.
Having thus fully described my said Invention, and the manner of
performing the same, I wish it understood that I claim,—
First. The key or "transmitter" shown in Figure 1 composed of the
bar K with its insulated stop i and levers 7, 1, as herein set forth, and for
the purpose specified.
Second. The combination of the said key or transmitter with a con-
denser or other compensator, as set forth and illustrated in Figures 1, 2,
and 8, for the purpose specified.
Third. The combination of the said key or transmitter with an
electro-magnet or other receiving instrument and batteries B' and B³,
as set forth and as illustrated in Figure 1, for the purpose specified.
Fourth. The combination of the said key or transmitter with a branch
or compensating circuit R, h, as set forth and as shown in Figure 1 for
the purpose specified.
Fifth. The use of a submarine cable in place of a condenser in
"duplex" telegraphy."
Sixth. A submarine cable constructed as described in connection with
Figure 2 of the Drawings.
Seventh. The combination of a cable so constructed with an electro-
magnet or other receiving instrument when used, as herein set forth and
for the purpose specified.
Eighth. The key or transmitter K with the jointed lever and
adjustable springs so arranged that it shall directly or indirectly,
during its upward or downward movement, press for an instant upon the
tongue a¹ of the relay or other movable part of the receiving instrument
to balance or neutralize the effect upon the said receiving instrument of
the static charge and discharge.
Ninth. The combination of the balancing or netralizing device
shown in Figure 3, with the double-lever transmitter shown in Figure 1
of the Drawings.
Tenth. Connecting a condenser or other "compensator" in a distinct
and separate circuit so that it shall receive its charge through a special-

page_text: wire, helix or electro-magnet from the signalling battery, as herein
described and as shown in Figure 14, or from a special battery as herein
described and as shown in Figures 4, 5, and 6, and return its charge
through the same separate circuit and special wire helix or electro-
magnet so placed as to act upon the receiving instrument in order to
balance or neutralize the effect of static-charge and dischargo upon the
receiving instrument.
Eleventh. Connecting an induction-magnet or coil in a distinct and
separate circuit, so that the current generated in said magnet or coil by
the movements of its armature, or the movements of another magnet
or coil in proximity to it, will be discharged through a special wire,
helix, or electro-magnet, so placed as to act upon the receiving instru-
ment in order to balance or neutralize the effect of the static charge and
discharge upon the said instrument, as herein described and as shown in
Figure 7 of the Drawings.
Twelfth. Connecting one wire or helix of a compound or double helix
induction magnet or coil in a distinct and separate circuit, so that the
current generated in this wire or helix by passing the current of the
signalling battery, or of a special battery, through the other wire or
helix of the induction magnet or coil, shall be discharged through a
special wire, helix, or electric-magnet, so placed as to act upon the
receiving instrument in order to balance or neutralize the effect of the
static charge and discharge upon the said instrument as herein described
and as shown in Figure 8 of the Drawings.
Thirteenth. A key or transmitter so constructed that when it is
closed and the current from the signalling battery flows to the line
it shall directly or indirectly cause an additional retractile force to act
upon the moveable part of the receiving instrument in order to
prevent its movement under the influence of the outgoing current
only, as herein described and as shown in Figures 9, 10, and 11 of the
Drawings.
Fourteenth. A permanent electro or electro permanent magnet so
placed that its momentary movements to the right or left by means of
the movements of the transmitter will prevent or check the movement
of the movable part of the receiving instrument in an opposite direction
by the effect of the static charge and discharge, as herein described and
as shown in Figure 12 of the Drawing.

page_text: Fifteenth. An electro-magnet so placed that its force and polarity
(varied by shunts or other well known means under control of the
transmitter) will prevent the movement of the movable part of the
receiving instrument by the effect of the static charge and discharge, as
described and shown in Figures 12 and 13 of the Drawings.
Sixteenth. A short circuit or "cut out," or a shunt controlled by the
transmitter, and so connected that the movements of the said trans--
mitter will vary the resistence of the compensating circuit with the
polarity of the currents sent into the line or cable, as herein described
and as shewn in Figure 15 of the Drawings.
Seventeenth. A transmitter so constructed and connected that it sends
the current from the signalling battery or batteries, not directly to the
line and compensating circuit, but into one set of plates of a condenser.
The other set of which is connected both to the line and the com-
pensating circuit, as described and as shown in Figures 17 and 18 of the
Drawings.
Eighteenth. In combination with a receiving instrument and a sig-
nalling line or cable, a compensating circuit so connected to a condenser
or a series of condensers, that the current of the signalling battery flows
into them but not past them to the earth, as herein described, and as
shown in Figures 17 and 18 of the Drawings.
Nineteenth. A high resistance placed in or attached to the said com-
pensating circuit and to the earth, so that a portion of the current
may, if desired, be drawn from the compensating circuit to the earth,
as herein described and as shown in Figures 17 and 18 of the Drawing.
J. B. STEARNS. (L.S.)
Witness to the signature.
of J. B. Stearns,
DOMINIC ELLIS COLNAGHI,
Her Britannic Majesty's Consul,
Florence.