IMPROVEMENTS IN APPARATUS FOR TRANSMITTING AND RECEIVING SIGNALS BY MEANS OF ELECTRICITY
Year: 1880

page_text: LETTERS PATENT to Arthur French St. George, of 40, Southampton Buildings:
"
in the County of Middlesex, for an Invention of IMPROVEMENTS IN
APPARATUS FOR TRANSMITTING AND RECEIVING SIGNALS BY MEANS OF
ELECTRICITY.”
PROVISIONAL SPECIFICATION left by the said Arthur French St. George
at the Office of the Commissioners of Patents on the 27th August 1880.
ARTHUR FRENCH ST. GEORGE, of 40, Southampton Buildings, in the County of
Middlesex. "IMPROVEMENTS IN APPARATUS FOR TRANSMITTING AND RECEIVING
SIGNALS BY MEANS OF ELECTRICITY."
My Invention relates to novel methods of arrangement of apparatus to be used
for the purpose of acoustical telegraphy by means of electricity, and it has for its
objects the attainment of greater simplicity and efficiency than in apparatus for
similar purposes of the kind ordinarily heretofore constructed and used. I take
an induction coil of a kind similar to that described in the Specification of Letters
Patent granted to me, dated June 1st, A.D. 1878, and numbered 2193, in which
the outer coil of wire surrounds an inner coil containing a metallic bar or core,
opposite to which a diaphragm is arranged.
include the said outer coil in the line circuit, or the wire extending between
the places, between which signals are to be transmitted, and in the same circuit I
also include any suitable form of battery or generator of electricity. I complete
the circuit of the inner coil arranged as above described by a resistance coil or
other suitable apparatus of any of the ordinary well-known kinds, offering sufficient
resistance to the passage of electrical currents, and preferably arranged so that the
amount of such resistance may be varied as desired."
Or, sometimes, I complete the circuit of the said inner coil of wire by connecting
its extremities together, either directly or with the intervention of the device well
known as a condenser, one extremity of the coil being connected to one side of
such condenser and the other extremity to its other side; and in some cases I
arrange a resistance apparatus, the amount of resistance of which may preferably
be made variable, across the extremities of the wires, joined as described to the
condenser so as to form a shunt, by means of which more or less of the current
may be made to pass to the condenser plates.

page_text: By means of apparatus arranged in the way described the internal wire of the
induction coil, having the vibrating diaphragm adjusted opposite to its metallic
core, is used solely for the purpose of receiving or taking up and responding audibly
to all electrical signals or communications, or any electrical variations which may
be occurring upon the main or line circuit which passes through the outer wire of
the induction coil. In order to transmit signals through my improved apparatus
arranged as described the ordinary method may be used, in which telegraphic or
telephonic signals are transmitted to the line circuit by inserting any convenient form
of telegraphic or telephonic transmitter in such line circuit, with or without a battery
or other generator of electricity, or by placing such transmitter, with or without such
battery or generator, in an independent or local circuit which influences the line
circuit by induction in such manner that any electrical pulsations or signals
produced when desired in such local circuit by the transmitter induce corre-
sponding pulsations or signals in the line circuit, which are transmitted to the
receiving instrument, and there observed or recorded.
By my novel arrangement of apparatus advantage is gained in the efficiency
and certainty with which electrical currents of any character transmitted at a high
speed are received and resolved into sonorous or audible vibrations. Any
convenient form of coils may be used, arranged in the various circuits as described,
and the inner core which they surround may be made of any suitable form. A
novel arrangement of core which I sometimes use consists of a sufficient number of
flat bars arranged radially at equal distances apart, in end view, and secured
together, or of a single bar having a cross section similar in shape to that of such
set of bars so connected together, the two coils of wire surrounding such core, and
preferably following its sectional contour. Another part of my Invention consists
in a novel form and arrangement of apparatus, by means of which sonorous
vibrations of the air produced by any sound are made to impinge upon the elements
of a thermo-electric generator of any of the well-known kinds, in which electricity
is generated by the unequal heating of dissimilar elements in such manner as to
cause variations in the electrical current produced by such generator, which
variations are transmitted directly along the line circuit by inserting the
transmitting apparatus in such line circuit or by placing it in an independent
circuit so arranged as to induce similar corresponding variations in the line
circuit.
The transmitting apparatus consists preferably of elements arranged in the
circuit in contact, but moveable, so that sonorous vibrations disturb their relation
and cause corresponding electrical variations in the current given out by the
thermo-electric generator and passing through them. Sonorous vibrations may be
made to effect this transmitting apparatus with or without the intervention of any
suitable diaphragm, tympan, armature, or their equivalents. In order to receive
such signals or vibrations at any desired point or points in the line circuit I prefer
to arrange at each such point a receiving apparatus consisting of a thermo-electric
generator of a kind similar to that just described, in which the elements are set in
sonorous vibration to a sufficient mechanical or molecular extent by every electrical
variation occurring in the circuit in which such apparatus is included, or in a
circuit capable of influencing by induction the circuit in which such apparatus is
included. Electrical variations so produced or induced in the said circuit containing
the apparatus cause vibrations, mechanical or molecular, or both, amongst the
elements of the generator, and give rise to sonorous vibrations, which may be heard
either with or without a diaphragm or its equivalent. The dissimilar elements of
the thermo-electric generators described may be heated in any convenient way,
but preferably by means of wires offering high resistance to the passage of electricity
through them, and surrounding but not in contact with the generator, which is
heated by the wires, which themselves become hot when a sufficient quantity of
electricity is passed through them.
Another part of my Invention consists in a novel arrangement of apparatus for the
purpose of producing vibrations in a diaphragm by means of currents of electricity.

page_text: For this purpose I arrange a magnetic or electro-magnetic bar opposite to one of the
poles, on which I adjust and fix a metallic diaphragm, armature, or their equivalent,
which is thus drawn or bent towards the pole. Between the pole and the diaphragm
I arrange, preferably spirally, a wire or coil, the ends of which are connected with
the circuit through which the signals are to be transmitted. When variations are
produced by the transmission of signals in the electricity traversing this wire, they
produce corresponding variations in the magnetism operating between the diaphragm
and the pole, the field of which they traverse and affect, and corresponding
vibrations are consequently produced in the diaphragm, audible signals being the
result.
The other end of the bar may be bent round to present its pole to the reverse
side of the diaphragm, a second wire being interposed between them, care being
taken that the direction of the currents of electricity is such as not to neutralize
each other. The metallic wire or coil described may be surrounded by a second
coil, the electrical variations in the inner one being caused by induction, in a manner
similar to that already herein before described.
Another part of my Invention relates to apparatus in which signals are trans-
mitted by the vibration of a diaphragm or armature, the variations in such
vibrations being regulated by the corresponding variations in the current of
electricity passing through a wire. I take a diaphragm adjusted and fixed in such
manner that its vibrations influence and transmit corresponding currents of
electricity to the point or points to which signals are to be transmitted, and in order
to produce such vibrations in the diaphragm I connect it to a light wire or support
at right angles to its surface. This wire, or a friction piece connected to it, is
pressed laterally by a spring against the periphery of a wheel or roller which is
made to revolve at a uniform speed by hand or other power, so that when the
wheel is revolving the diaphragm is drawn slightly out of its normal plane by the
friction of the wheel against the wire. Connected to the said wire is a second
wire or attachınent at right angles, the outer end of which is connected to a second
diaphragm which can be set into vibration when desired by sound through a mouth-
piece, or in any other convenient way. The action of the apparatus is as follows:-
The wheel or cylinder being rotated, the first diaphragm is drawn and retained
uniformly more or less out of its normal plane. When the second diaphragm is
then set in vibration, each such vibration varies the pressure of the wire or friction
piece upon the wheel, and consequently varies in a corresponding way the position
of the first diaphragm, in which accordingly a series of vibrations is set up precisely
corresponding with those in the first, and transmitting similar vibrations and
audible signals to the receiving instruments upon the line circuit.
:-

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Arthur French St. George in the Great Seal Patent Office on the
26th February 1881.
ARTHUR FRENCH ST. GEORGE, of 40, Southampton Buildings, in the County of
Middlesex. "IMPROVEMENTS IN APPARATUS FOR TRANSMITTING AND RECEIVING
SIGNALS BY MEANS OF ELECTRICITY."
My Invention relates to novel methods of arrangement of apparatus to be used
for the purpose of acoustical telegraphy by means of electricity, and it has for its
objects the attainment of greater simplicity and efficiency than in apparatus for
like purposes of the kinds ordinarily heretofore constructed and used.
In order to put my Invention in operation I take an induction coil of a kind
similar to that described in the Specification of Letters Patent granted to me dated
June 1st, A.D. 1878, and numbered 2193, in which an outer coil of insulated wire,
surrounds an inner coil of insulated wire containing a metallic bar or core
opposite to which a diaphragm is arranged. I include the said outer coil in
the line circuit, that is to say, the wire extending between the places
between which signals are to be transmitted, and in the same circuit I also
include any suitable form of battery or generator of electricity. I complete the
circuit of the inner coil of insulated wire arranged as above described by a resistance
coil or other suitable apparatus of any of the ordinary well known kinds, by
which sufficient resistance may be offered to the passage of electrical currents,
and preferably arranged so that the amount of such resistance may be varied
as desired. Or sometimes I complete the circuit of the said inner coil of wire by
connecting its extremities together, either directly or with the intervention of the
device well known as a condenser, one extremity of the coil being connected to one
side of such condenser and the other extremity to its other side; and in some cases
I arrange a resistance apparatus, the amount of resistance of which may preferably
be made variable, across the extremities of the wires joined as described to the
condenser so as to form a shunt, by means of which more or less of the current
may be made to pass to the condenser plates as may be desired. Or sometimes I
leave the ends of the inner coil of insulated wire disconnected, the circuit being
left uncompleted. In using the method of arrangement described and shewn in
the Specification and Drawings of my said former Letters Patent already referred
to, I sometimes use a horse shoe shaped iron bar, or a straight or horse shoe shaped
steel bar permanently magnetic, or a similar soft iron bar made into an electro magnet
in the usual way when desired, and I fit upon or add to one or both of the
extremities or poles of such straight or bent bars the metallic bar or bundle of
wires and double coils of insulated metallic wire arranged as described in my said
Specification. The coils, when arranged upon both such poles, may have one or
both of the inner coils of insulated wire so connected as to form part of the local
circuit or circuits above described, and either one or both such inner coils may be
provided with an outer coil, one or both of which may form a part or parts of the
main line circuit.
By the methods of arrangement of apparatus described, the internal wire of the
induction coil, which has the vibrating diaphragm adjusted at a proper distance
opposite to its metallic core, used solely for the purpose of receiving or taking up
by induction and responding audibly to all electrical signals or communications,
or to any electrical variations which may be occuring upon the main or line circuit
which passes through the outer wire of the induction coil, and of which the latter
forms a part. In order to transmit signals through my improved apparatus
arranged as described, the ordinary method may be used, in which telegraphic or
telephonic signals are transmitted through the line circuit by inserting any
convenient form of telegraphic or telephonic transmitter in such line circuit, with

page_text: or without a battery or other generator of electricity. This method of arrangement
is illustrated in Figures 1 and 2 of the accompanying Drawings, which are in
illustration of my Invention. a is the metallic bar surrounded with an internal
coil band an external coil c of insulated wire; d is a vibrating diaphragm; e is
the main line wire, through which the current is transmitted round the external
coil e by any suitable form of transmitting apparatus f in any desired part of the
circuit, the current then passing by the wire g back through the earth or through
a return wire; is a resistance apparatus, the amount of resistance of which can
be varied and adjusted as desired, which placed in the circuit of the inner coil b.
Or instead of the arrangements described, I sometimes place the transmitter, with.
or without a battery or generator, in an independent or local circuit which
influences the main line circuit e by induction, in such manner that any electrical
pulsations or signals produced when desired in such local circuit by the transmitter,
induce corresponding pulsations or signals in the line circuit e, which are
transmitted to the receiving instrument in the manner described, and there observed
or recorded. By my novel arrangement of apparatus as described and shewn,
advantage is gained in the efficiency and certainty with which electrical currents
of any character [transmitted at a high speed are received and resolved into
sonorous or audible vibrations. The disturbing noises which are heard in a
telephone when it is connected with a line or conductor exposed to the inductive
action of neighbouring independent telegraph or other electrical conductors or
wires in which electrical currents are occuring may be neutralized to a considerable
extent by the arrangement of an adjustable resistance apparatus, which is included
in the circuit of the inner coil, as shewn in Figure 2, in which a is the bar; b and
c, the inner and outer coils; d, the vibrating diaphragm; e, the main line wire;
f, transmitting apparatus; g, the return wire; h, a variable and adjustable resistance
apparatus; whilst i is any suitable form of battery or generator of electricity.
Or an adjustable resistance apparatus may be used, acting as a "shunt" across
the terminals of a condenser of the kind well known and ordinarily used, which
condenser has one set of its plates connected to one extremity of the inner coil
wire, and the other set of plates connected to the other extremity of the inner coil,
as shewn in Figure 3, in which is the condenser arranged so that the current
through the inner coil c may be made to pass as desired to it, or through the
resistance coil h. The disturbing currents induced in the main line, and which it is
desired to suppress or neutralize, pass through the outer coil of the receiving
telephone and induce corresponding currents in the inner coil. These induced
currents produced as described in the inner coil pass in a direction opposite and
opposed to that of the currents passing through the outer coil.
By this means and by suitably adjusting the variable resistance apparatus a
certain point can be attained at which the disturbing currents are to a certain
extent suppressed or neutralized by the opposing action upon the metallic bar or
core, caused by the opposing currents in the two coils surrounding such bar or core,
and which bar or core actuates the diaphragm, and consequently the objectionable
noises are neutralized. The condenser shewn at in Figure 3 is not specially
necessary for neutralizing "induction" noises, but it is found to be necessary for
the efficient working of the apparatus upon long lines of any considerable inductive
capacity or other unfavourable electrical conditions upon which retardation of
electric currents transmitted is found to take place. The object of arranging the
condenser in connection with the inner coil of the receiving telephone, as shewn in
Figure 3, is to cause an electrostatic induction between the two coils b and c when
a current is received in the outer coil c from the line e, and I find it in some cases
an improvement to connect one set of plates of the condenser above mentioned to
earth or return wire, as shewn at e in Figure 4. I sometimes make the inner coil
moveable and separate from the outer coil, and so arranged that it can be caused to
move lengthways when desired along the metallic bar or core within it in such a
manner that the inner coil may be withdrawn more or less from the inside of the
outer one which surrounds it.

page_text: This method of arrangement is illustrated in Figure 5, in which the inner coil b
is shewn connected by means of rods m, m¹, to a handle n, so that it may be
withdrawn more or less from the outer coil c, sliding at the same time upon the
central bar a, which is firmly supported by the attachment o, shewn separately in
Figure 6. Sometimes instead of the arrangement shewn I prefer to make the outer
coil moveable and so arranged that it can be conveniently caused to slide more or
less over or entirely off the inner coil, or in some cases I make both coils moveable
in the manner described.
The coils or coil made to be capable of being shifted, as described, for the purpose
of adjusting the inductive action between the two coils, may be arranged in
any of the manners already described. I do not confine myself to the precise
method of causing one or both coils to slide longitudinally for the purpose of
adjustment of their inducing action upon each other, but I employ any other
convenient equivalent method for such purpose, and the metallic bar or core
contained in them may also be capable of adjustment in its position in reference to
the diaphragm, armature, tympan, or their equivalent.
It is important to construct one or both of the coils of a telephone in such a
manner that the wire of which they are composed shall be capable of being adjusted
in the closest possible proximity to the diaphragm without being in contact, and
also that the insulated wire of an outer coil shall be in the closest possible
proximity to the insulated wire of the inner coil. I facilitate this object by
winding the requisite quantity of wire for a coil upon a bobbin of the proper size
capable of being taken to pieces, then thoroughly saturating the wire thus
contained upon the bobbin with melted paraffin wax, shell lac, or other suitable
insulating material or composition, which will cause the convolutions of wire to
adhere to each other and solidify the coil to such an extent that the bobbin being
taken to pieces and removed the solid coil of wire remains in its proper position
and shape and requires no bobbin to hold it intact.
The barrel and ends of the bobbins as ordinarily used in telephones being in this
way dispensed with, the internal surface of the outer coil can be brought into
closer proximity with the external surface of the inner coil which the outer coil
surrounds. Also the end surface of the coil or coils exposed to the diaphragm can
be brought nearer to the latter, which, with the closer proximity of the two
coils to each other, constitute a great advantage gained in the working of the
telephones.
Any convenient form of coils may be used arranged in the various circuits, as
described, and the inner core which they surround may be made of any suitable
form.
A novel arrangement of such core which I sometimes use consists of a
sufficient number of flat bars arranged radially at equal distances apart in end
view and secured together, as shewn in Figure 7, or of a single bar having a cross
section similar in shape to that of such set of bars so connected together, or of
other desired shape, as shewn in Figure 8, the two coils of wire surrounding such
core and preferably following its sectional contour. The core bars of such shape,
as described, may constitute one or both of the ends or poles of an ordinary straight
or horse-shoe shaped bar, or they may be made separate and attached to one or
both of such ends or poles. And such core bars of the novel shape described may
either be used in combination with simple single coils or with double coils arranged
either in the ordinary way or according to the Specification of my former Letters
Patent, already hereinbefore referred to.
Another part of my Invention consists in a novel form and arrangement of
apparatus by means of which sonorous vibrations of the air produced by any sound
are made to impinge upon the elements of a thermo-electric generator of the well
known kind in which electricity is generated by the unequal heating of dis-similar
elements in such manner as to cause variations in the electrical current produced.
by such generator, which variations are transmitted directly along the line circuit
by inserting the transmitting apparatus in such line circuit, or by placing it in an

page_text: independent circuit so arranged as to induce similar corresponding variations in the
line circuit, in the manner already described.
The transmitting apparatus consists preferably of elements arranged in the
circuit in contact but moveable, so that sonorous vibrations disturb their relation
and cause corresponding electrical variations in the current given out by the
thermo-electric generator and passing through them. Sonorous vibrations may be
made to affect this transmitting apparatus, with or without the intervention of any
suitable diaphragm, tympan, armature, or their equivalents. One method of
arrangement of apparatus for this purpose is illustrated in Figure 9, in which a is
a bar or pencil of carbon, one end of which is carried by the metallic support b
(of German silver or other suitable material which forms one of the thermo-electric
elements), to which is connected the wire c of the circuit.
The other end of the carbon bar a rests in a recess or cavity in the carbon block d,
which is capable of being heated by a lamp or other source of heat placed below it,
and the heat from which passes through it.
Instead of a single bar of carbon, as shewn at a, a number of such bars may be
arranged radially round the block d, which latter may be attached by its upper
surface to an ordinary vibrating diaphragm, the whole apparatus being arranged
in any convenient position. Any other suitable materials may be used as the
thermo-electric elements instead of carbon' and German silver as described, and the
entire thermo-electric apparatus may be varied in its form and character to suit
varying circumstances. The apparatus just described serves as a transmitting
apparatus, and in order to receive signals or vibrations transmitted by it at any
desired point or points in the line circuit, I prefer to arrange at such point a
receiving apparatus consisting of a thermo-electric generator of a kind similar
to that just described, in which the elements are set in sonorous vibration to a
sufficient mechanical or molecular extent by every electrical variation occuring in
the circuit in which such apparatus is included, or in a circuit capable of influencing
by induction the circuit in which such apparatus is included, in the manner
hereinbefore described.
Electrical variations so produced or induced in the said circuit containing the
apparatus cause vibrations, mechanical or molecular, or both, amongst the elements
of the generator, and give rise to sonorous vibrations which may be heard either
with or without a diaphragm or its equivalent. The dissimilar elements of the
thermo-electric generators described may be heated in any convenient way and in
some cases by means of wires offering high resistance to the passage of electricity
through them, and surrounding but not in contact with the generator, which is
heated by the wires, which themselves become hot when a sufficient quantity of
electricity is passed through them.
Another part of my Invention consists in a novel arrangement and construction
of apparatus for the purpose of producing vibrations in a diaphragm by means of
currents of electricity. In order to put in operation this part of my Invention I
arrange a magnetic or electro-magnetic bar, opposite to one of the poles of which I
adjust and fix a metallic diaphragm, armature, or their equivalent, which is thus
drawn or bent toward the pole. I adjust the pole and the diaghragm at such a
distance apart that between them can be arranged a wire or coil bent spirally, or
backward and forward in a plane parallel to the diaphragın, the ends of which wire
are connected with the circuit through which the signals are to be transmitted.
When variations are produced by the transmission of signals in the electricity
traversing the wire, they produce corresponding variations in the magnetism
operating between the diaphragm and the pole, the field of which they traverse and
affect, and corresponding vibrations are consequently produced in the diaphragm,
audible signals being the result. The other end of the bar may be bent round to
present its pole to the reverse side of the diaphragmn, a second wire being
interposed between them, care being taken that the direction of the currents of
electricity is such as not to neutralize each other. The metallic wire or coil
described may be surrounded by a second coil, the electrical variations in the inner

page_text: one being caused by induction, in a manner similar to that already herein before
described. This part of my Invention is illustrated in Figures 10, 11, 12, 13, 14,
and 15. In Figures 10 and 11, a is the permanent bar magnet, the pole of which
is adjusted opposite to the vibrating diaphragm b. Between the pole and the
diaphragın is interposed the wire c, which is arranged in a spiral form, or in a series
of folds or bends backward and forward, as shewn in Figure 11, in a plane parallel
to the diaphragm b.
In Figure 12 an electro-magnet is shewn at a instead of a permanent bar
magnet. In Figure 13 the electric current in the wire c is induced by the variable
or intermittent currents passing through an outer coil e instead of the current
passing directly through the latter. In Figure 14, instead of a bar magnet, a
horseshoe magnet a, either permanent or electro magnetic (as shewn) is used, a
spiral or folded wire c, c¹, being interposed between each of the poles of the magnet
and the diaphragm b. In Figure 15, a horse shoe permanent or electro-magnet a
is shewn, having the diaphragm b arranged between its poles, a spiral or folded
wire c, c¹, being arranged on each side of the diaphragm b and between it and the
poles of the magnet m. Or the spiral or folded wire may be arranged and used
upon one side only of the diaphragm.
The last part of my Invention relates to apparatus in which signals are trans-
mitted by the vibration of a diaphragm or armature, the variations in such
vibrations being regulated by corresponding variations in the current of electricity
passing through a wire. In order to put this part of my Invention in operation I take
a diaphragm adjusted and fixed in such manner that its vibrations influence and
transmit corresponding currents of electricity to the point or points to which
signals are to be transmitted, and in order to produce such vibrations in the
diaphragm I connect it to a light wire or support at right angles to its surface.
This wire or a friction piece connected to it is pressed laterally by a spring against
the periphery of a wheel or roller, which is made to revolve at a uniform speed by
hand or other power, so that when the wheel is revolving the diaphragm is drawn
slightly out of its normal plane by the friction of the wheel against the wire.
Connected to the said wire is a second wire or attachment at right angles, the
outer end of which is connected to a second diaphragm which can be set into
vibration when desired by sound through a mouthpiece or in any other convenient
way. Figure 16 is in illustration of apparatus constructed as above described.
a is a vibrating diaphragm, which when set in telephonic vibration induces and
transmits corresponding currents of electricity in the usual way through the wires
e, e¹. The diaphragm a is connected to a light friction piece b, which is pressed
against the periphery of the wheel c with a pressure which can be varied and
adjusted as desired by the elastic pressure block d and screw f. Connected to the
wire or friction piece b is a light wire g, the outer end of which is connected to the
end of the second vibrating diaphragm h, which can be set in telephonic vibration
by the mouthpiece i or in other convenient way. The wheel c can be made to
revolve sufficiently uniformly at any desired speed by the wheels and handle at k.
The action of the apparatus is as follows:-The wheel or cylinder e being made
to rotate the first diaphragm a is drawn, and retained uniformly more or less out
of its normal plane. When the second diaphragm h is then set in vibration each
such vibration varies the pressure of the wire or friction piece b upon the wheel c,
and consequently varies in a corresponding way the position of the first diaphragm
a, in which accordingly a series of vibrations is set up, precisely corresponding with
those in the diaphragm h, and transmitting similar vibrations through the wires
e, e¹, and audible signals to the receiving instrument upon the line circuit in
connection with those wires.
Having now described my Invention, and the manner in which it is to be
performed, I claim,-
The method of arranging telephones with an outer coil of insulated wire in the
main line circuit with a suitable transmitting apparatus, and with or without a
battery or generator in the same circuit, surrounding an inner coil of insulated wire

page_text: containing a metallic core operating a vibrating diaphragm, such inner coil of wire
being connected with an adjustable fixed or variable resistance apparatus, sub-
stantially as and for the purposes described and shewn; also, the method of leaving
such inner coil with its ends disconnected, or with one of such ends connected to
the earth or to the return wire, substantially as hereinbefore described; also, in
combination with such apparatus so arranged a condenser apparatus connected
with the circuit of the inner coil of insulated wire, and so arranged that the whole
or more or less of the electricity induced in such wire may be passed to the con-
denser apparatus as described, substantially as and for the purposes described and
shewn; also, in such apparatus, the method, as described and shewn, of connecting
the condenser apparatus to the earth or to the return main line wire if desired;
also, in combination with such apparatus, the method of producing electrical
currents in the main line wire by induction from a separate independent or local wire
circuit, substantially as described; also, in telephones, the methods of moving
lengthways the outer coil, or the inner coil, or both coils, substantially as and for
the purposes described and shewn; also the method of constructing, arranging, and
solidifying the coils of telephones, so that they can be used without supporting
bobbins, substantially as and for the purposes described.
Also the method of making the inner cores of telephones of a sufficient number
of bars of suitable section, arranged radially and secured together, or of a single
bar of similar shape in cross section, substantially as described and shewn; also, in
telephones, the method of attaching cores so formed to the end or ends of bars of
the ordinary shape, substantially as described and shewn; also the method of
constructing, arranging, and applying thermo-electric appliances by means of which
telephonic signals are transmitted, substantially as herein described and shewn;
also the method of producing vibrations in a diaphragm adjusted opposite to the
pole or poles of a magnet by means of one or more wires arranged spirally, or in
folds backward and forward, or other convenient form between the pole or poles
and the diaphragm in a plane parallel to the diaphragm, through which wire or
wires variable or intermittent currents of electricity are made to pass, substantially
as and for the purpose described and shewn.
Also, the method of producing variable or intermittent currents of electricity in
such wire or wires, so arranged by means of induction from a separate coil or coils
of wire through which corresponding variable or intermittent currents of electricity
are passed, substantially as described and shewn.
Also, the apparatus consisting of a vibrating diaphragm, the vibrations of which
cause electrical currents and signals to be transmitted through wires, a diaphragm
set in vibration by the voice or other sound, and a wheel or drum set in revolution
when required, in combination with a wire or friction piece pressed against the
wheel or drum by an adjustable screw and elastic pressure block, and a connecting
wire or link between the second diaphragm and the wire or friction piece, all
substantially as and for the purposes described and shewn in the Drawing.
In witness whereof, 1, the said Arthur French St. George, have hereunto set
my haud and seal, this 26th day of February, in the year of our Lord
1881
ARTHUR FRENCH ST. GEORGE. (L.S.)
Witness,
E. EDWARDS,
Of 40, Southampton Buildings,
London.