Distance Telegraph Lines and particularly Submarine and Subterranean Cables.
Year: 1884

page_text: Distance Telegraph Lines and particularly Submarine and
Subterranean Cables.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "AN IMPROVED
SYSTEM OF RECEIVING RELAY APPARATUS FOR LONG DISTANCE TELEGRAPH LINES
AND PARTICULARLY SUBMARINE AND SUBTERRANEAN CABLES," a communication to
me from abroad by Louis Maiche of 3 Rue Louis le Grand, Paris, France, Electrical
Engineer, to be as follows:-
This invention relates to a system of apparatus designated a receiving relay
which is applicable to all long distance telegraph lines and particularly to sub-
marine and subterranean cables. As is well known the currents received through
conductors of great length or which are subject to considerable leakage (such as
submarine and subterranean cables) are exceedingly weak and in order to register
the signals represented by them it is necessary to use instruments of great
sensitiveness and delicacy such as the mirror galvanometer and the siphon recorder
which give respectively visual and written signals based on the Morse Code, the
currents in one direction representing the dashes and those in the opposite direction
the dots constituting the conventional signs of this code.
The currents which traverse submarine cables being much too weak to actuate
relays for working through a local circuit recording or printing instruments such
as the Morse and Hughes receivers, the receiving instruments heretofore proposed
for rendering sensible the direct indications of the line current, have been very
sensitive and consequently very delicate and difficult of regulation. This invention
has for its object to enable writing and printing instruments such as those of
Morse and Hughes, to be actuated by very weak line currents.
In principle, the invention consists in causing the emission between two points
of an apparatus suitably arranged, of an induction spark, a statical spark, or a
brush discharge, in vacuo, in an atmosphere of air or gas rarefied or not. The spark

page_text: emitted between these two points is in the position which I will call, the position
of "useless discharge" that is to say it produces no effect on the recording
apparatus.
The spark or brush discharge emitted between these two points is so arranged in
the instrument, as to be capable of alteration in its position under the influence
of the magnetic effects developed by the line currents traversing the coils of
the instrument. By this alteration of position under the influence of the passage
of one of these currents, the spark or brush ceases to play between the two first
mentioned points, but is emitted from the first one only of these points and passes
to a third point or electrode suitably arranged for the purpose. In this second
position which I designate the position of "useful discharge" the spark or brush
acts on the recording instruments. To this end the discharge of this spark or
brush is caused to pass through the fine wire of an induction coil, termed a
"reconstitution" coil, the effect being to produce in the coarse wire of the coil, an
induced current of quantity, capable of working a relay or other apparatus.
In order that the invention may be more readily understood I have illustrated
in the accompanying diagrams, a few examples of apparatus based on the principle
above mentioned.
Figure 1 shows the general arrangement of the apparatus when a brush discharge
is used. Figure 2 represents a modified arrangement in which a brush discharge is
also used. Figure 3 illustrates an arrangement in which an induction spark is
used. In these several figures the same letters of reference indicate analogous
parts.
In figure 1 a is a capacity either vacuous or containing a rarefied atmosphere of
any kind, in the sides of which are mounted three points or conductors b, c, d, of
any suitable form. e is an induction coil of which the primary wire is in
connection with the poles of a local battery f at the receiving station and the
This coil which may
secondary wire g is connected to the two conductors b and c.
be replaced by a statical machine or any other apparatus capable of furnishing
electrical discharges, permits of the emission between the conductors bc of
brushes whenever required.
When the apparatus is at rest, the circuit of coil e is broken but when a message
is announced, the connections above indicated are to be established.
h is an electro-magnetic apparatus (a simple coil with or without soft iron core)
traversed by the line current. When a line current passes through the wire i of
this coil, the effect is to attract the discharge x which is caused to deviate from its
path and becomes emitted in the direction ¹ between the electrodes c, d instead
of b c.
The discharge being no longer able to pass by the wire 9 passes through the
wire and traverses the fine wire of the reconstitution coil before returning to
the wire g and electrode c.
This discharge induces in the coarse wire m of the reconstitution coil a current
of quantity which will actuate a relay R or other suitable apparatus. This last
named result being thus obtained it will be readily understood that it will be easy
to work in this way any suitable receiving or recording instrument such as those
of Morse and Hughes, since at every passage of a line current in the wire i of
coil h, the relay will be closed and will actuate the receivers suitably arranged
with their batteries in a local circuit. When no line current is passing, the
discharge may continue to be emitted without affecting the transmission, since it
is what has been designated as the "useless" discharge from 6 to c through wire g
only. At z on the circuit of wire g is interposed a coil which may be similar to
that used for the reconstitution of the current serving to actuate the relay.
This coil is intended to equalize the resistances, so that the spark will pass with
equal ease when it is used for the purpose of reconstitution as when it is lost in
useless discharge.
If desired the arrangement might be duplicated by placing an electrode at a¹ and
a second coil at h¹, so as to have two different useful discharges (one between c d

page_text: and the other between c d³) according to the direction of the line current
traversing the coils h h¹.
The modified arrangement illustrated in figure 2 differs from the former only in
so far that the electric discharge instead of being free and actuated directly by the
line current follows the movement of a galvanometer needle n placed in the
receiver a and influenced by the coils h, h¹ traversed by the line currents. Here as
in the former case there are three electrodes b c d and the useless discharge takes
place between b c and the useful discharge between c, d, the same effects being
produced as before described. It is therefore unnecessary to further describe this
arrangement the operation and the constituent parts of which are similar to that
first described.
In the third arrangement illustrated in figure 3, an induction spark is employed
instead of a brush discharge. For this purpose a magnetic needle n is suspended
between the coils h, h of the apparatus of what ever kind, by which it is to be
moved under the influence of the passage of the line currents. Opposite to this
needle, which communicates by its axis o with the secondary wire g of the
induction coil e, are arranged two other needles or electrodes c and d When no
current is passing in the line wire i and coils h h¹ the needle n whose point is
nearer to c than to d, is vertical and the spark is emitted between n c and the
current returns directly by wire g, to coil e; this is the useless discharge. But
when a line current passes in the proper direction in wire i, the coils h h¹ influence
the needle n which is thereby moved towards the left thus receding from c and
approaching d. When the distance n d becomes less than the distance n c, the
spark is emitted between n and d instead of between n and c. This is the useful
discharge which traverses the fine wire k of the reconstitution coil 1, thereby
actuating the relay as above described.
It should be observed that this invention is absolutely independent of the form
and construction of the apparatus, which constitute it by their combination and
operation as above specified.
As before stated the coil e which furnishes the spark or discharge may be
replaced by any other apparatus static or otherwise, capable of fulfilling the same
purpose. Similarly the electro-magnetic arrangement h h¹ which influences the
spark or discharge, and the magnetic needles n may be arranged in any other
suitable way, without departing from the invention. Further in lieu of three
electrodes b c d or needles n c d as above described, I may use any desired number
of magnetic needles or electrodes for obtaining either with a single spark or
discharge or a number of different sparks or discharges, a series of useful and
useless discharges suitably grouped according to the arrangement of the stations to
be served and the object to be attained.
I may also cause the current reconstituted in the coarse wire m of the
reconstitution coil 1, to act on any desired system of relay or recording or
signalling instrument or on a number of such relays or instruments at once. The
apparatus would moreover be provided with all necessary accessories, such as
manipulators, commutators, galvanometers, lightning protectors &c. which it is
unnecessary to describe here, as they are in ordinary use for telegraphic purposes.
Dated this 13th day of December 1884

page_text: An Improved System of Receiving Relay Apparatus for Long
Distance Telegraph Lines and particularly Submarine and
Subterranean Cables.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "AN IMPROVED
SYSTEM OF RECEIVING RELAY APPARATUS FOR LONG DISTANCE TELEGRAPH LINES
AND PARTICULARLY SUBMARINE AND SUBTERRANEAN CABLES" (a communication to
me from abroad by Louis Maiche, of 3 Rue Louis le Grand, Paris, France, Electrical
Engineer), and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention relates to a system of apparatus, designated a receiving relay,
which is applicable to all long distance telegraph lines and particularly to
submarine and subterranean cables.
As is well known, the currents received through conductors of great length or
which are subject to considerable leakage (such as submarine and subterranean
cables) are exceedingly weak and in order to register the signals represented by
them it is necessary to use in-truments of great sensitiveness and delicacy such as
the mirror galvanometer and the siphon recorder which give respectively visual
and written signals based on the Morse code, the currents in one direction
representing the dashes and those in the opposite direction the dots constituting
the conventional signs of this code.
The currents which traverse submarine cables being much too weak to actuate
relays for working through a local circuit recording or printing instruments, such
as the Morse and Hughes receivers, the receiving instruments heretofore proposed
for rendering sensible the direct indications of the line current have necessarily
been very sensitive and consequently very delicate and difficult of regulation.
This invention has for its object to enable recording or printing instruments such
as those of Morse and Hughes, to be actuated by very weak line currents.
In principle, the invention consists in causing the emission between two points
of an apparatus suitably arranged, of an induction spark, statical spark, or a brush
discharge, in vacuo, in an atmosphere of air or gas rarefied or not. The spark
emitted between these two points is in the position which I will call the position
of "useless discharge" that is to say it produces no effect on the recording
apparatus. The spark or brush discharge emitted between these two points is so
arranged in the instrument, as to be capable of alteration in its position under the
influence of the magnetic effects developed by the line currents traversing the coils
of the instrument. By this alteration of position under the influence of the passage
of one of these currents, the spark or brush plays no longer between the two first
mentioned points, but between the first one only of these points and a third point
or electrode suitably arranged for the purpose. In this second position, which I
designate the position of "useful discharge," the spark or brush acts on the
recording instruments. To this end, the discharge of this spark or brush is caused
to pass through the fine wire of an induction coil termed a "reconstitution" coil,
the effect being to produce in the coarse wire of the coil, an induced current of
quantity, capable of working a relay or other apparatus.

page_text: In order that the invention may be more readily understood, I have illustrated
in the accompanying diagrams, a few examples of apparatus based on the principle
above mentioned. Figure 1 shows the general arrangement of the apparatus when
a brush discharge is used. Figure 2 represents a modified arrangement in which a
brush discharge is also used. Figure 3 illustrates an arrangement in which an
induction spark is used. In these several figures the same letters of reference
indicate analogous parts.
In figure 1 a is a chamber which may either be vacuous or may contain a
rarefied atmosphere of any kind. In the sides of this chamber are mounted three
points or conductors b c d, of any suitable form. e is an induction coil of which the
primary wire is in connection with the poles of a local battery f at the receiving
station and the secondary wire g is connected to the two conducting points b and c.
This coil which may be replaced by a statical machine or any other apparatus
capable of furnishing electrical discharges, permits of the emission between the
conductors b c of a brush discharge x whenever required.
When the apparatus is at rest, the circuit of coil e is broken but when a message
is announced, the connections above indicated are to be established.
The
h is an electro-magnetic apparatus (a simple coil with or without soft iron core)
traversed by the line current. When a line current passes through the wire i of
this coil the discharge x is caused to deviate from its path and assume the
position wherein it plays between the electrodes c d instead of b c.
discharge being no longer able to pass by the wire g passes through the wire kand
traverses the fine wire of the "reconstitution" coil before returning to the wire g
and electrode c.
.
This discharge induces in the coarse wire m of the "reconstitution" coil a current
of quantity which will actuate a relay R or other suitable apparatus. This last
named result being thus obtained it will be readily understood that it will be easy
to work in this way any suitable receiving or recording instrument such as those of
Morse and Hughes, since at every passage of a line current in the wire i of coil h,
the relay will be closed and will actuate the receivers suitably arranged with their
batteries in a local circuit. When no line current is passing the discharge may
continue to be emitted without affecting the transmission since it is what has been
designated as the "useless discharge" from 6 to c through wire g only. At in the
circuit of wire g is interposed a coil which may be similar to that used for the
reconstitution of the current serving to actuate the relay. This coil is intended to
equalize the resistances, so that the spark will pass with equal ease when it is used
for the purpose of reconstitution as when it is lost in "useless discharge."
If desired the arrangement might be duplicated by placing an electrode at d¹ and
a second coil at h¹ so as to have two different useful discharges (one between c d
and the other between c d¹) according to the direction of the line current traversing
the coils h h'.
"
The modified arrangement illustrated in figure 2 differs from the former only in
so far that the electric discharge instead of being free and actuated directly by the
line current follows the movement of a galvanometer-needle n placed in the
receiver a and influenced by the coils h h¹ traversed by the line currents. Here, as
in the former case, there are three electrodes b c d and the "useless discharge
takes place between b c and the "useful discharge" between cd, the same effects
being produced as before described. It is therefore unneces-ary to further describe
this arrangement, the operation and the constituent parts of which are similar to
that first described.
In the third arrangement illustrated in figure 3 an induction spark is employed
instead of a brush discharge. For this purpose a magnetic needlen is suspended
between the coils h by the passage though which of the line currents it is
influenced or moved. This needle communicates by its axis o with the secondary
wire g of the induction coil e and opposite to it are arranged two other needles or
electrodes c and d. When no current is passing in the line wire i and coils h h³, the
needle n whose point is nearer to c than to d, is vertical and the spark is emitted

page_text: between mc and the current returns directly by wire g, to coil e; this is the
"useless discharge." But when a line current passes in the proper direction in
wire i, the coils h h¹ influence the needle n which is thereby moved towards the
left thus receding from c and approaching d. When the distance n d becomes less
than the distance n c, the spark is emitted between n and d instead of between n
and c. This is the "useful discharge " which traverses the fine wire k of the
reconstitution coil 7, thereby actuating the relay as above described.
It should be observed that this invention is not dependent on the form and
construction of the apparatus, which constitute it by their combination and
operation as above specified.
As before stated the coil e which furnishes the spark or discharge may be
replaced by any other apparatus static or otherwise, capable of fulfilling the same
purpos. Similarly the electro-magnetic arrangement h h¹ which influences the
spark or discharge, and the magnetic needle n may be arranged in any other
suitable way without departing from the invention. Further in lieu of three
electrodes b c d or needles n c d as above described, I may use any desired number
of magnetic needles or electrodes for obtaining either with a single spark or
discharge or a number of different sparks or discharges, a series of "useful" and
"useless" discharges suitably grouped according to the arrangement of the stations
to be served and the object to be attained.
I may also cause the current reconstituted in the coarse wire m of the
reconstitution coil 7, to act on any desired system of relay or recording or signalling
instrument or on a number of such relays or instruments at once.
The apparatus would of course be provided with all necessary accessories, such as
manipulators, communicators, galvanometers, lightning protectors &c which it is
unnecessary.to describe here as they are in ordinary use for telegraphic purposes.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
"
1st A system of receiving relay apparatus for long distance telegraphy, wherein
an electrical spark or discharge (or more than one) derived from any suitable
source, is (or are) caused to vary in direction under the influence of the passage of
a line current through a coil and thereby to assume a position either of "useless
or of "useful" discharge, the discharge or discharges in the latter position passing
through a so called "reconstitution" coil or its equivalent for the purpose of pro-
ducing a current capable of actuating a relay and a Morse, Hughes or other
receiving instrument substantially as specified.
2nd In a receiving relay apparatus for long distance telegraphy, the combination
of an induction or statical apparatus furnishing an electrical spark or discharge, an
apparatus provided with fixed or movable conductors or electrodes between which
the sparks or discharges are emitted, an electro-magnetic apparatus capable of
directly or indirectly influencing the sparks or discharges in such a way as to vary
their position between the conductors or electrodes, and a so-called "reconstitution"
coil acting on a relay or a recording apparatus, the whole arranged and operating
substantially as described and shown in the drawings.
Dated this 12th day of September 1885.