IMPROVEMENTS IN APPARATUS APPLICABLE TO TELEPHONY AND TELEGRAPHY
Year: 1884

page_text: I, JOHNSTON STEPHEN, of Ravelston Cottage, Blackhall, in the County of
Midlothian, North Britain, Journalist do hereby declare the nature of the said
invention for IMPROVEMENTS IN APPARATUS APPLICABLE TO TELEPHONY AND
TELEGRAPHY to be as follows:-
This Invention, which relates to improvements in apparatus applicable to
telephony and telegraphy, has for its object to give an individual call to, and to
switch into circuit, any one of a number of instruments placed adjacent to a line
wire, while, at the same time preventing any other instruments from being inserted
in the circuit.
In carrying out this Invention, an instrument is constructed to transmit along
the line wire, alternate currents of positive and negative electricity at any required
uniform speed. To effect this, there may be used the ordinary pedal arrangement
operated by hand and having its rate of transmitting regulated according to the
vibrations of a metronome or other adjustable standard arranged for the guidance
of the operator; or, the form of instrument known as the drop handle or barrel
commutator transmitter, or other means may be employed for alternating, by
hand, the currents of electricity with any uniform speed.-A transmitting
instrument may be employed which shall itself automatically effect the trans-
mission of alternating currents of electricity with any speed for which it may have
been previously adjusted.-The motive power for such instrument may be clockwork,
or it may be derived from the current which it, at the time, is transmitting, or
from an auxiliary current of electricity. One form of instrument for automatically
transmitting alternating currents, consists of a coil of insulated wire wound upon
a core which may be hollow, but which is preferably wound upon a disc of soft
iron. This coil is pivoted at or about its centre upon a horizontal axle which is
supported at, or near, its ends upon bearings.-This coil is hung in such relation
to a magnetic field, which may be formed from one or more magnets, as to have an
intense dynamic effect produced, when a current of electricity passes round the said
coil. The vibratile coil, so constituted, and so situated relatively to a magnetic
field, will tend, on currents of electricity passing through it, to deflect in either
direction from its vertical line, according as the currents are of positive or negative
electricity. The vibratile coil is provided with one or more rods, on which are

page_text: placed two or more weights, any one or more of these weights being adjustable
upon the rod or rods, thereby admitting of the rate of vibration of the pivoted coil
to be adjusted. One terminal of the vibratile coil is electrically connected with
the line wire, the other terminal being electrically connected to an electrically
conducting rod or plate which, at each semi-vibration of the coil, make electrical
contact with the positive or negative pole of a battery or other source of electricity,
provision being made for that pole of the battery which, at the time, is not
connected with the line, being put to earth. One method of carrying this into
practice is by attaching the wires from the positive and negative poles of a battery
or other source of electricity, to two conducting pallets insulated from one another
and whose lower ends normally, that is to say, when the pendulum is at rest, lie
against a conducting plate electrically connected with earth.-Upon deflection of
the coil to one side or another one or other of these pallets is lifted off the earth
plate, electrical connection with which is thereby broken, the electrical connection
being made through the.said uplifted pallet with the conducting plate in electrical
connection with one terminal of the said coil.-It will thus be seen that the two
poles of the battery or other source of electricity, are alternately brought into
connection, through the vibratile coil, with the line, and that currents of positive
or negative electricity will pass into and through the said vibratile coil and along
the line, the said currents serving to maintain the oscillation of the transmitting
instrument, and to cause to oscillate the coils of the receiving instruments_which
are substantially similar in construction to the transmitting instrument.-Each of
the receiving instruments has a vibratile coil capable of oscillating with a definite
and fixed period proper to itself. When then electrical impulses are transmitted
which are unisonant in period with the period of the vibratile coil of any one
receiving instrument only that particular coil will attain amplitude of oscillation.―
One method of effecting the temporary throwing into circuit of any one of the
receiving stations is by electrically connecting the line wire, at entering the said
receiving station, to the hinge of a pivoted fall contact, upon the back of which,
when the said fall contact is in its normal position, there presses a spring which
is in electrical connection with one terminal of the vibratile coil, the other
terminal being electrically connected to the line wire on its exit from the
station. The fall contact is held in its normal position by a pivoted latch which
can be raised either by the vibratile coil or its connections being caused to
impinge, when it shall have attained amplitude of oscillation, upon one end of
the said latch; or the said latch can be raised by hand by means of a rod, which is
free to slide upwards through the base board of the instrument. The fall contact,
when it has fallen by either of the herein before mentioned means, breaks electrical
connection with the vibratile coil of its own station and consequently with all those
coils in the series, which intervene between it and the line's connection with
earth. The descent of the fall contact causes it to make electrical connection with
a wire which is connected with one of the terminals of the telephonic or telegraphic
post, the other terminal of the said telephonic or telegraphic post being either led
direct to earth, or through the line and the further vibratile coils in the series to
earth.
It is to be understood that the descent of the fall contact may be caused to effect
the same results by means other than those herein before described.
"
For the temporary locking out of all the receiving station's instruments save that
instrument which is temporarily in electrical connection with the main line, there
is arranged at each of the stations an electro-magnet, preferably of horse-shoe form,
which is wound with two sets of coils, to be hereinafter referred to as the "upper
pair of coils, and the "lower" pair of coils.-The "upper" pair of coils, at each
station, is connected in series with a line, one end of which terminates in an
insulator, the other end being connected either with earth, or with a pole of a
battery whose other pole is led to earth.-The "lower" pair of coils at each station
is connected similarly in series with a line, one end of which terminates in an
insulator, said insulator being at that end where the wire, connected with the

page_text: upper "coil passes either to earth or to the battery connected in the manner
hereinbefore described, while at its other end this wire connected in series with the
"lower" coils, passes to the pole of a battery. It will be understood, that when
a battery is employed instead of an earth connection, for the wire which passes
round the "upper" coils, the poles of the batteries which are connected with the
conducting wires of the "upper" and "lower" coils, are attached to opposing
poles, while the correspondingly opposing poles of the batteries are connected with
earth.
The fall contact hereinbefore referred to, is made of two conducting sections
insulated from one another, the one being used for the telephonic or telegraphic
posts as herein before described, the other being employed to operate the locking
out arrangement. One method for effecting this purpose is, to connect each of the
said sections of the fall contacts for operating the locking out arrangement, at all
the stations, through its hinge with the conducting wire which passes round the
"lower" coils, and on its descent it forms an electrically conducting bridge between
the wires of the "upper" and "lower" coils.-The descent of the fall contact may
be caused to close the connection between the two wires in any other manner.—
It will thus be seen that upon the closing of connection between the wires passing
round the upper" and "lower" coils the energising of all the electro-magnets in
the circuit is effected.-These electro-magnets, so energised, attract armatures which
may be employed for retaining all the fall contacts in their normal position; or, it
may be caused to draw or push a pin into or through an opening formed in the rod
which passes upwards through the base board of the instrument, so preventing the
said rod from being moved to raise the latch.
""
It is preferred that the switching arrangement hereinbefore described, be placed
under a cover wholly or partly of glass or its equivalent, secured by a lock in such
manner that the sole access to the said switch, be by the hereinbefore mentioned
rod passing upwards through the base board, and by a second rod or its equivalent
for replacing the fall contact in its normal position. The energising of the electro-
magnets may also be caused to operate an indicator at each station, each of which
indicators is formed of two discs upon one of which is inscribed
Free" or a
synonymous word, this disc being normally opposite to a window of clear glass
which may be formed in the enclosing case, the other disc having the word
Engaged or its synonym inscribed thereon. Upon the energising of the electro-
magnet the "Free" disc is caused to pass from before the window while the
Engaged" disc is brought opposite to it.
"
"
"

page_text: Improvements in Apparatus Applicable to Telephony and
Telegraphy.
I JOHNSTON STEPHEN of Ravelston Cottage Blackhall in the County of Mid-
lothian North Britain Journalist do hereby declare the nature of said invention
for IMPROVEMENTS IN APPARATUS APPLICABLE TO TELEPHONY AND TELEGRAPHY
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
This Invention which relates to Improvements in apparatus applicable to
telephony and telegraphy has for its object to give an individual call to and
to switch into circuit any one of a number of instruments placed adjacent to a
line wire while at the same time preventing any other instrument from being
inserted in the circuit.
In carrying out this Invention an instrument is constructed to transmit along
the line wire alternate currents of positive and negative electricity at any required
uniform speed. To effect this there may be used the ordinary pedal arrangement
which is shewn in diagram in Figure 1 operated by hand or the form of
instrument known as the drop handle or barrel commutator transmitter or other
means may be employed for alternating by hand the currents of electricity with
any uniform speed. The rate of transmitting by hand as aforesaid may be
regulated according to the vibrations of a metronome or other adjustable standard
arranged for the guidance of the operator A. transmitting instrument such as
Maelzel's metronome may be employed which shall itself automatically effect the
transmission of alternating currents of electricity with any speed for which it may
have been previously adjusted. The motive power for this instrument may be
clockwork or it may be derived from the current which it at the time is trans-
mitting or from an auxiliary current of electricity. One form of instrument for
automatically transmitting alternate currents is illustrated by the diagram figure 2.
It consists of a coil of insulated wire a wound upon a core which may be hollow
but which is preferably wound upon a disc of soft iron. This coil is pivoted at or
about its centre upon a horizontal axle b which is supported at or near its ends
upon bearings. This coil is hung in such relation to a magnetic field (which may
be formed from one or more magnets c) as to have an intense dynamic effect
produced when a current of electricity passes round the said coil. The vibratile
coil so constituted and situated relatively to a magnetic field will tend on currents
of electricity passing through it to deflect in either direction from its vertical line
according as the currents are of positive or negative electricity The vibratile coil
is provided with one or more rods (as indicated at d) on which are placed two or
more weights (as shewn at d²) any one or more of these weights being adjustable
upon the rod or rods, thereby admitting of the rate of vibration of the coil a to be
adjusted One terminal x of the vibratile coil is electrically connected with the
line wire the other terminal being electrically connected to an electrically con-

page_text: ducting rod or plate ƒ carried by the axis b which plate at each semi-vibration of
the coil a makes electrical contact with the positive or negative pole of a battery
or other sourse of electricity, provision being made for that pole of the battery
which at the time is not connected with the line being put to earth which may be
effected by a split battery as indicated in the drawing. A method of carrying this
into practice is as indicated by the diagram Figure 3 by attaching the wires from
the positive and negative poles of a battery or other source of electricity, to two
conducting pallets g, g² insulated from one another their lower ends normally (that
is to say, when the pendulum is at rest) lying against a conducting plate i
electrically connected with earth. Upon deflection of the vibratile coil a to one
side or another one or other of these pallets g or g² is lifted off the earth plate i by
the conducting portion f so that electrical connection with the said plate i is
thereby broken the electrical connection being made through the said uplifted pallet
with the conducting portion f in electrical connection with one terminal of the
said coil. It will thus be seen that the two poles of the battery or other source
of electricity, are alternately brought into connection, through the vibratile coil
with the line, and that currents of positive or negative electricity will pass into
and through the said vibratile coil and along the line, the said currents serving
to maintain the oscillation of the transmitting instrument, and to cause to oscillate
the coils of the receiving instruments which are substantially similar in con-
struction to the transmitting instrument. Each of the receiving instruments has
a vibratile coil capable of oscillating with a definite and fixed period proper to
itself. When then electrical impulses are transmitted which are unisonant in
period with the period of the vibratile coil of any one receiving instrument only
that particular coil will attain amplitude of oscillation. The method of effecting
the temporary throwing into circuit of any one of the receiving stations is as
indicated by Figure 4 by electrically connecting the line wire at entering the said
receiving station, to the hinge of a pivoted fall contact j upon the back of which,
when the said fall contact is in its normal position there presses a spring which
is in electrical connection with one terminal of the vibratile coil a the other
terminal being electrically connected to the line wire on its exit from the station.
The fall contact j is held in its normal position by a pivoted latch which can be
raised either by the vibratile coil or its connections being caused to impinge when
it shall have attained amplitude of oscillation, upon one end 12 of the said latch, or
the said latch can be raised by hand by means of a rod, which is free to slide
upwards through the base board of the instrument as indicated by the dotted lines
at 13.
The fall contact ; when it has fallen by either of the hereinbefore mentioned
means breaks electrical connection with the vibratile coil of its own station and
consequently with all those coils in the series which intervene between it and the
lines connection with earth. The descent of the fall contact causes it to make
electrical connection with a wire m which is connected with one of the terminals
of the telephonic or telegraphic post, the other terminal of the said telephonic or
telegraphic post being either led direct to earth (as at E) or through the line (as
at x) and the further vibratile coils in the series to earth.
It is to be understood that the descent of the fall contact ; may be caused to
effect the same results by means other than those herein before described.
"
For the temporary locking out of all the receiving stations instruments save that
instrument which is temporarily in electrical connection with the main line, there
is arranged at each of the stations an electro magnet n Figure 5 preferably of horse
shoe form which is wound with two sets of coils, to be hereinafter referred to as
The "upper
the "upper" pair of coils (p. p.) and the "lower" pair of coils (99).
pair of coils at each station is connected in series with a line y one end of which
terminates in an insulator y² the other end being connected either with earth or
with a pole of a battery whose other pole is led to earth as shewn The "lower
pair of coils at each station is connected similarly in series with a line zone end
of which terminates in an insulator at 2ª said insulator being at that end where the
"

page_text: wire, connected with the "upper" coil, passes either to Earth or to the battery
connected in the manner hereinbefore described-while at its other end this wire
connected in series with the "Lower" coils passes to the pole of a battery. It
will be understood, that when a battery is employed instead of an Earth connec
tion, for the wire which passes round the "upper" coils the poles of the batterics
which are connected with the conducting wires of the "upper" and "lower" coils,
are attached to opposing poles while the correspondingly opposing poles of the
batteries are connected with Earth.
The fall contact hereinbefore referred to, is made of two conducting sections³
(Fig. 6) insulated from one another, the one j being used for the telephonic or
telegraphic posts as hereinbefore described, the other being employed to operate
the locking out arrangement, One method for effecting this purpose, is, to connect
each of the said sections of the fall contacts for operating the locking out arrange-
ment, at all the stations through its hinge with the conducting wire z which passes
round the "lower" coils and on its descent it forms either directly or indirectly an
electrically conducting bridge between the wires y and z of the "upper" and
"lower" coils.
It will thus be seen that upon the closing of the connection between the wires
passing round the "
upper" and "lower" coils the energising of all the electro
magnets in the circuit is effected. These electro-magnets so energised, attract
armatures (indicated at r in Figure 5) which may be employed for retaining all
the fall contacts in their norinal position or it may be caused to draw or push a pin
into or through an opening formed in the rod which passes upwards through the
base board of the instrument, so preventing the said rod from being moved to raise
the latch.
Figure 7 shews the general arrangement of the instrument in which the parts
can be readily identified as they are marked with the same letters as those used in
the preceding diagrams. In this Figure 7 the locking pin is shewn upon the
armature actuated by the electro magnet and is marked s. It enters the hole in
the rod 13 to lock it when the armature is drawn over by the magnet.
It is preferred that the switching arrangement herein before described is placed
under a cover as shewn in the said Figure 7 wholly or partly of glass or its
equivalent, secured by a lock in such manner that the sole access to the said switch,
be by the herein before mentioned rod 13 passing upwards through the base board
and by a second rod t or its equivalent for replacing the fall contact in its normal
position. The said rods are operated by the finger lever u u The energising of
the electro-magnets may also be caused to operate an indicator at each station, each
of which indicators is formed of two discs mounted on a lever w upon one of which
disc is inscribed "Free" or a synonomous word this disc being normally opposite
to a window of clear glass which may be formed in the enclosing case, the other
disc, having the word "Engaged" or its synonym inscribed thereon. Upon the
energising of the electro magnet the "Free" disc is caused to pass from before the
window while the "engaged "disc is brought opposite to it.
Figure 8 is a diagram representing a part of an installation arranged on the
herein before described system. The parts which are here indicated are marked
with the same letters of reference as those used to denote corresponding parts in
the preceding diagrams.
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
First. The general arrangement and combination of devices constituting the
system of improved apparatus for telephonic and telegraphic purposes substantially
as herein before explained.
Second. The arrangement of electrically operated mechanism for automatically
transmitting currents of electricity with any previously determined speed consisting

page_text: of a coil of wire operating in relation to a magnetic field substantially as herein-
before described.
Third. The use in combination with a time marker of a commutator operated
by hand for the purposes and substantially as hereinbefore described.
Fourth. The hereinbefore described means for temporarily locking out all
instruments save the two required to be in use at any one time.
Fifth. The use with telephonic and telegraphic apparatus of mechanism for
operating an indicator to denote when the line is free or in use the said mechanism
being arranged and combined substantially as herein before described.