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 27th January 1874, and dated the 1st September 1873.
PROVISIONAL SPECIFICATION left by the said Joseph Barker Stearns
at the Office of the Commissioners of Patents, with his Petition,
on the 1st September 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 as follows:-
My Invention relates to electric telegraph apparatus, and consists in
various improvements whereby the said apparatus is rendered more
efficient and reliable than heretofore, as will appear from the following
description;

page_text: It is a fact well known in telegraphy that a submarine or subterranean
telegraph wire, cable, or line, and in a lesser degree also a "land line "
or suspended telegraph wire or line as used in the transmission of signals,
is not only a conductor of electricity, but is also a receiver of electricity,
in the sense that a Leyden jar is a receiver.
If the key of the instrument is adjusted to cause a current of electricity
from the battery to flow into and through the cable or line a portion of
this current will be absorbed by the line, which thus becomes charged,
and this charge is technically called the "static charge."
If after the line has received its charge from the battery the key is
adjusted to break contact therewith and form another contact with a wire
leading to the earth and connected with. an instrument, the charge will
flow back or return from the line and pass through the said instrument
to the earth. In duplex telegraphing this charge and discharge become
troublesome, therefore condensers or induction apparatus have been
employed to obviate their effects upon the receiving instruments, as
described in the Specification of Letters Patent granted to me
November 11th, A.D. 1872, No. 3344. But as a condenser of exactly
the desired capacity is not always readily obtained some means for
adjusting its effect upon the receiving instrument become desirable:
I accomplish this object in the following manner :-In a telegraph
apparatus wherein the wires from the transmitting instrument arc
coiled in opposite directions around the cores of a differential relay and
connected one
to the cable and the other to an artificial line or rheostat
provided with a condenser, if the wire from the said condenser is con-
nected to the artificial line, and the key of the instrument is adjusted to
send the current from the battery around the poles of the relay to the
cable, and in an opposite direction around the poles of the relay, and
through the artificial line to the earth, both the cable and the condenser
will receive "charge." And if the said key is reversed the charge from
the cable and also from the condenser will pass around the poles of the
relay in opposite directions to the earth. If these two charges are
equal in amount and pass in equal times no effect will be produced upon
the relay, but if the charge from one is in excess of that from the other
the excess will effect the said relay and a false signal will be given. If
however a portion of the artificial line is included between the instru- ·|
ment and the point of attachment of the condenser the latter will receive.

page_text: a smaller charge than before, because the tension of the battery has
become reduced at this point of attachment by the resistance. And
this reduced charge on returning will be divided, a portion only passing
to earth around the poles of the relay, the remainder passing to earth
5 through the other portion of the artificial line. By this arrangement a
condenser of any capacity, greater than that of the line or cable, may be
employed.
In case the condenser is of less capacity than the line or cable I.
introduce resistance between the instrument and the line at such a point
O as will reduce the tension of the battery and diminish the charge taken
by the line.
Sometimes I provide an artificial escape, which has the effect of
drawing off a portion of the charge from the cable, while the whole
charge from the condenser returns through the instrument, and I
5 sometimes provide such artificial escapes at several points throughout
the line for a like purpose, and thereby a condenser of less capacity than
the line or cable may be used. If the said line or cable is of consider-
able length it will receive and give up its charge more slowly than the
condenser, and although the amount of charge and discharge from each
be equal a true working balance will not be obtained.
To cause the condenser to take and give up its charge more slowly I
insert a resistance coil between the artificial line and the condenser in
the wire connecting them, or where there are two or more condensers I
place resistance coils in the said wire between the several condensers, or
in wires connecting each condenser separately with the said wire, I make
these resistance coils either like ordinary resistance coils, or with one
wire and with or without cores. They may be made either with fixed or
variable amounts of resistance, and when provided with cores the latter
are sometimes made adjustable, so that they may be partially or wholly
removed, whereby the amount of magnetism imparted to them by the
charge and consequently the amount of retardation of the charge may
be varied. If these resistances are arranged one after the other along
the wire connecting the condensers with the artificial line, the charge
from cach condenser will be retarded more than that of the one before it,
and if placed between this wire and the condensers the charge from
each condenser may be retarded to any desired extent independently of
the others. By these means the charge from all of the condensers may

page_text: be made to exactly equal that from the line, both in its amount and in
the time of passing through the receiving instrument or relay, and also
with regard to the distribution of the amount of charge during the
time.
In working lines or cables with the duplex system it is sometimes
found advantageous to employ polarized relays, as stated in the said
former Specification: In such cases I arrange the apparatus as follows:-
The polarized relay or other polarized apparatus is connected with a
working battery and a reversing or clearing battery. The resistance
coils, the line, the rheostat, and wires together form what is known as
the "Wheatstone-bridge." The polarized differential relay may however
be substituted for the bridge, the key and the batteries remaining
unchanged.
:
]
I do not confine myself to any particular form of reversing key, but I
prefer to employ, a reversing key worked by an clectro-magnet, local 1
battery, and finger key, as the action of this key is more sure and
uniform than that of the ordinary finger key.
As a substitute for the aforesaid condenser I sometimes use an
induction coil or series of such coils to neutralize the effect of the
"static charge," and its discharge upon the receiving instrument, as
described in the said former Specification. I make these coils either
with or without iron cores, but prefer them with the cores, which may
be made adjustable, so that they may be partially or wholly removed
from the coils for the purpose of varying their magnetism, and con-
sequently their effect upon the receiving instrument.
As another substitute for the said condenser I sometimes employ the
current from the sending battery or from a separate battery. The
current of the battery is thrown through the receiving instrument for an
instant by the following contrivance :-The said instrument is provided
with a spring in combination with the key, and which lies in contact
with a stud connected with one side of the receiving instrument. A
metallic pin is fitted through the bar of the said key and insulated from
the same. This pin is connected to one pole of the battery, the other
pole being connected to the other side of the said receiving instrument.
As the key is depressed the said pin will make contact with the spring
before the contact between the said spring and the stud is broken, and

page_text: during the interval the current of the said battery passes through the
receiving instrument.
Various other contrivances may be adopted for closing the circuit for
a brief period instead of the above spring; for instance, I may use a
metal piece carried by the bar of the key, or any moveable part of the
instrument, and fitted to slide over another metal piece.
A secondary battery composed of many small plates of one metal may
also be employed as a substitute for the condenser, the poles of the said
battery being connected to opposite sides of the receiving instrument.
Care must be taken to make the resistance of this battery (or the wire
by which it is connected) so great as not to shunt too much of the
current of the sending or main battery from the instrument. The said
metal plates should also be so adjusted that they will give and take up
charge very quickly. A condenser may be connected in the same
manner to opposite sides of the said instrument.
In working long lines or cables, the so-called "earth currents"
sometimes become so troublesome as to seriously interfere with or
entirely prevent signalling. When this is the case, a second wire or
cable is sometimes substituted for the earth, the circuit being then.
wholly metallic. This is termed "looping.”
When using the duplex apparatus I arrange the apparatus for looping
with a duplicate wire or cable,, which takes the place of all earth
connections except that of the condenser. I use switches whereby the
apparatus is adjusted for ordinary working or for loop working, as
desired.
ATT 41 shows th
Jonions may be wond
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 28th February 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
BARKER STEARNS, of Boston, Massachusetts, United States of America,

page_text: now of No. 8, Southampton Buildings, London, Electrician, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of September, 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 exccutors, admi-
nistrators, 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 there-
after during the term therein expressed, should and lawfully might
make, usc, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an In-
vention 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 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 imme-
diately 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 Invention relates to electric telegraph apparatus, and consists in
various improvements whereby the said apparatus is rendered more
efficient and reliable than heretofore, as will appear from the following
description :-
It is a fact well known in telegraphy that a submarine or subterrancan
telegraph wire, cable, or line, and in a lesser degree also a land line"
or suspended telegraph wire or line as used in the transmission of signals
is not only a conductor of electricity, but is also a receiver of electricity
in the sense that a Leyden jar is a receiver.

page_text: If a line or cable, a battery, a key or contact maker, and-an instrument
for indicating or recording telegraphic signals are arranged, as in
Figure 1, and contact be made at a, the current from battery B will flow
into and through the line or cable L, and a portion of this current will
be absorbed by the line which thus becomes charged, and this charge is
technically called "static charge."
If after the line has received its charge from the battery the contact
be broken at a and a second contact be made at 6 the charge will flow
back from the line and pass through the instrument I to the earth, pro-
ducing a momentary disturbance of the instrument. In the system
known as duplex telegraphy this charge and discharge become trouble-
some, and condensers and also induction coils have been employed to
obviate their effect upon the receiving instruments, as described in the
Specification of Letters Patent granted to me November 11th A.D. 1872,
No. 3344.
A condenser of exactly the required capacity is not always readily
obtained, and therefore some means for adjusting the effect of a con-
denser upon the receiving instrument become desirable. I accomplish
this object in the manner illustrated in Figure 2, which shows a telegraph
apparatus wherein the wires p, y, from the transmitting apparatus are
coiled in opposite directions around the cores o of a differential relay I,
p being connected to the line and y to the compensating circuit or
rheostat R, . If the wire h from a condenser c is connected to terminal
3 of the receiving instrument I, its other pole going to earth, and the
key is closed to send the current from battery B around the core of the
rclay I to the line L, and in an opposite direction around the core of I
and through the compensating circuit R, h, to the earth at E, both the
line L and the condenser C will receive charge, and if the said key is
then opened or its position reversed the charge from the line L and also
from the condenser C will return and pass around the core of the relay I
in opposite directions to the earth at E³. If these two charges are equal
in amount and pass in equal times no effect will be produced upon the
relay I, but if the condenser charge is in excess of that from the line
the excess will effect the said relay and a false signal will be made. If
however a portion R of the compensating circuit is included between
the relay and the point of attachment of the condenser at 6, Figure 2,
the condenser will receive a smaller charge than before, because the
tension of the battery current has become reduced at this point of

page_text: attachment by the resistance R, and this reduced charge on returning
will divide at b, a portion only passing to earth around the cores of the
relay, the remainder passing to earth through R¹, R³, R.
By this
arrangement a condenser of any capacity greater than that of the line
or cable may be employed.
If the condenser is of less capacity than the line or cable I connect
the wire to terminal 3 and introduce resistance at » between the
instrument and the line L, thereby reducing the tension of the current
and causing the line to take a smaller charge than before, while the
condenser will still take a maximum charge.
Sometimes I provide an artificial "escape" or leak as at j, Figure 2,
which has the effect of 'drawing off a portion of the charge from the
line, while the whole charge from the condenser returns through the
instrument I, and I sometimes provide such artificial leaks at several
points upon the line for a like purpose. In this manner a condenser of
less capacity than the line or cable may be used. If the line or cable is
of considerable length it will receive and give up its charge more slowly
than the condenser, and although the amount of the charge and dis-
charge from both may be equal a true working balance will not be
obtained.
In Figure 3 I have shown a contrivance for causing the condenser to
take and give up its charge more slowly than the condenser. I insert a
resistance coil x between the terminal 3 and the condenser O in the wiro
connecting them, or if there are two or more condensers I place similar
coils between the several condensers in the wires connecting them as at
x¹, x², x³. In the latter case the charge of each condenser will be
retarded more than that of the one before it, and the charge from all the
condensers will thus be made to resemble that from the line or cable.
Sometimes I insert these resistances in the wires, connecting the several
condensers to the wire l, as at x, x, x², Figure 4, and by varying these
resistances the charge from each condenser may be retarded to any
extent, independently of and without reference to the others. These
resistance coils may be made in the ordinary manner or may be wound
with a single wire, and may be either with or without iron cores. They
may be made either with fixed or vairable amounts of resistance, and
when provided with corcs the latter may be made adjustable so that they
be partially or wholly removed to vary the amount of magnetism
may

page_text: imparted to them by the charge, and consequently the amount of re-
tardation of the charge. By these means the charge from all of the said
condensers may be made to exactly equal that from the line both in its
amount and in the time of passing through the receiving instrument I,
and also in the distribution of the charge during this time.
"
In working telegraph lines or cables with the duplex system it is
sometimes found advantageous to employ polarized relays, or other
polarized instruments, and to reverse the polarity of the current when
signalling by means of a reversing key. In such cases I arrange the
apparatus as shown in Figure 5, where P is the polarized instrument;
B, the battery, whose current is reversed by the movements of the
reversing key D; and A, A', arc resistance coils. The said resistance
coils, the line, and the rheostat R, h, together with the instrument P,
form what is known as the "Wheatstone bridge. The polarized
différential relay may however be substituted for this bridge. If the
battery is divided, and a part of it placed at B', this part will not be
reversed by the movements of the key K, and by making the division
unequally any desired portion of the current may be reversed. If the
battery is divided equally, as shown in the diagram, Figure 5, no
current will pass to the line when D is open or in the position shown;
but when is closed the current of the whole battery passes out to
the line. I sometimes use two separate batteries, a marking battery B
and a spacing or clearing battery B', as shown in Figure 6. In this
case niether battery is reversed but currents of opposite polarities are sent
to the line from the separate batteries alternately by the movements of
the key K.
I do not confine myself to any particular form of reversing key, but
I prefer to operate the reversing key by an electro-magnet E, M,
local battery L, B, and finger key K, as the action of this key is more
sure and uniform than that of the ordinary finger key.
As a substitute for the aforesaid condenser I sometimes use an
induction coil, or a series of such coils to neutralize the effect of the
static charge and discharge upon the receiving instrument, as described
in the said former Specification. I make these coils either with or
without iron cores, but prefer them with the cores, which may be made
adjustable so that they may be partially or wholly withdrawn from the
coils for the purpose of varying their magnetism, and consequently their
effect upon the receiving instrument. The manner of applying these

page_text: induction coils is described in the Specification of the aforesaid Letters
Patent.
-
As another substitute for the condenser I sometimes employ the
current from the sending battery or from a separate battery, as shown
in Figure 7. The current of the battery B₁ is sent through the
receiving instrument for an instant by the following contrivance :-The
instrument is provided with a flexible bar or springs in combination
with the key k; this spring lies in contact with the stud v carried
by the lever of the key k, and this stud is connected to terminal 1 of
the receiving instrument. From terminal 3 of this receiving instrument
a wire extends to one pole of the battery B¹, and from the other pole
of this battery a wire extends to a second stud w. When the key is
closed the spring will make contact with the stud w at t before contact
between the spring & and stud v is broken at u, and during this interval
the current of the battery B' passes through the receiving instrument.
The duration of this current may be varied by varying the distance
between the studs and w. Other devices may be adopted for closing
the circuit for a brief period instead of the above spring. For instance,
I may use a metal piece carried by the bar of the key or any movable
part of the instrument, and fitted to slide over another piece of
metal.
'
A secondary battery H, Figure 8, composed of many plates of one
metal (and sometimes called Ritter's pile) may also be employed as a
substitute for the condenser, the poles of the said battery being
connected to opposite sides of the receiving instrument, or to a separate
magnet, as shown in Figure 9, care being taken in either case to make
the resistance of the battery (or of the wires by which it is connected)
so great as not to "shunt" too much of the current of the sending or
main battery from the instrument. The said plates should also be
so adjusted that they will take and give up charge quickly. The series
of plates may also be applied as at H¹, Figure 8, with one pole
connected to the earth and the other pole to its terminal 3, or otherwise;
but their action in all cases is the same, that is to say, they take charge
from the sending battery or some separate battery, and afterwards
gives up this charge through the receiving instrument, or some separate
compensating magnet or coil, as in Figure 9, for the purpose of
neutralizing the effect of the static charge from the line or cable upon
the receiving instrument.

page_text: In working long lines or cables the so-called earth currents sometimes
become so troublesome as to seriously interfere with or entirely prevent
the signalling. When this is the case a second line or cable is some-
times substituted for the earth, the circuit being then wholly metallic.
This arrangement is called "looping," and is illustrated in Figure 10.
When using the duplex apparatus I arrange the connections for
looping with a duplicate wire or cable L', which takes the place of all
earth connections, except that of the condenser.
When the switches or movable arms m, m³, m³, m³, are turned to the
left, as in the Diagram, the instruments are connected for working in
the ordinary manner; but when the arms are thrown to the right the
second wire or line L' takes the places of the earth, and the lines are
"looped." The arm m³ disconnects line L' from the instruments
ordinarily worked in connection with it.
All of the devices and arrangements above described and illustrated
may be used in combination with the bridge, the differential magnet,
or the balance magnets, as described in this and the said former
Specification.
Having thus fully described my said Invention, and the manner of
performing the same, I wish it understood that I claim,-
First. Including a portion of the compensating circuit between the
receiving instrument or relay and the point of attachment of the con-
denser, as herein described, and as illustrated in Figure 2, so that a
portion only of the charge from the condenser shall pass to earth
through the receiving instrument.
Second. Inserting resistance between the receiving instrument and
the line or cable herein described, and as illustrated in Figure 2, so that
the said line or cable shall take a smaller charge from the battery than
that taken by the condenser.
Third. Making an artificial escape or leak between the receiving
instrument and the line or cable as herein described, and as shown in
Figure 2, or at several points in the line or cable, for the purpose of
preventing the line or cable taking as high a charge as the condenser,
and so that a portion of the charge from the line or cable shall pass to
earth without going through the receiving instrument.

page_text: Thirteenth. The combination of a secondary battery with a polarized
instrument an ordinary electro-magnet, or other suitable instrument,
when the said secondary battery is used to neutralize the effect of static
charge from the line or cable upon said instruments.
Fourteenth. The combination of a secondary battery with a separate
electro-magnet, coil, or wire when such magnet, coil, or wire is employed
to neutralize the effect of the static charge upon the receiving
instrument.
•
Fifteenth. The combination of a secondary battery with the "Wheat-
stone bridge," the differential receiving instrument, or the balanced
receiving instrument, as herein described, and as shown in Figure 9,
for the purpose specified.
Sixteenth. The combination of a condenser with a polarized receiving
instrument for the purpose specified.
Seventeenth. The combination of induction coils with a polarized
receiving instrument-for the purpose specified:
Eighteenth. The combination of a receiving instrument, a rheostat or
compensating circuit, with a second line or cable, as herein described,
and as shown in Figure 10, for the purpose of obviating the effects of
earth currents upon the receiving instrument.
Nineteenth. The combination of a compensating battery with a
receiving instrument, as herein described, and as shown in Figure 7, for
the purpose specified.
Twentieth. Operating a reversing key of any form or construction by
means of an electro-magnet, local battery, and finger key when-used for
the purpose set forth.
J. B. STEARNS. (L.S.)