IMPROVEMENTS IN TELEPHONIC APPARATUS.
Year: 1880

page_text: LETTERS PATENT to Henry Harris Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"IMPROVEMENTS IN TELEPHONIC APPARATUS.". A communication from abroad
by Louis Maiche, of Paris, France.
PROVISIONAL SPECIFICATION left by the said Henry Harris Lake at the
Office of the Commissioners of Patents on the 7th August 1880.
HENRY HARRIS LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN TELEPHONIC APPARATUS.'
[A communication from abroad by Louis Maiche, of Paris, France.]
This Invention relates to improvements in telephonic apparatus or electrophones,
and is designed for facilitating the transmission of sounds to long distances.
For this purpose the said apparatus has to be combined with an ordinary
telephone which serves as a receiving instrument, repeating at a distance all tho
sounds that have acted upon the electrophone. The latter is very sensitive, and is
provided with means for calling the attention of the station or place with which
communication is desired.
This improved apparatus or electrophone consists substantially of pieces of carbon
or contacts mounted upon a bell or sonorous box or vessel made of suitable material
(preferably glass), the said carbons being placed as near as possible to the edge of the
said bell or sonorous box. These carbon contacts transform the sonorous vibrations
of the substance of the bell, in front of which the speaking is carried on, into
nechanical action, and the said vibrations produce differences of pressure between
the carbons, and consequently variations in the intensity of the current passing
through the said carbons. These variations of intensity produce induced currents
in a coil (say, a Ruhmkorff coil), and these induced currents are transmitted along
the line to actuate the receiving telephone.
By reason of a special arrangement which dispenses with the necessity of
employing an electric bell, as hereinafter described, my apparatus together with its
battery and a telephone form a complete set for a station.

page_text: In carrying the said Invention into practice, I provide a wooden box in which an
aperture is made; this box encloses a bell or sonorous box or vessel of glass. The
said glass vessel is open on one side, and is preferably made with a concave bottom;
the space between the walls of the sonorous glass vessel and the wooden box is
filled up with wadding. Upon the sonorous vessel are placed one above the other
the contact pieces made of carbon. These contact pieces are made of one or several
pairs of carbons, which are spherical in form, and which are arranged in such a
manner that their position may be regulated upon the end of metallic rods or
stems, which are hinged upon the walls of the wooden case or box at which points
two wires terminate; the current passes through these stems or rods. One of the
carbon balls by its own weight bears against the sonorous glass bell or vessel, and
the other carbon ball rests upon the first named carbon ball in a like manner. For
pressing the carbons against each other and against the wall of the glass bell, flat
springs may also be used which may or may not be adjustable. The said contact
balls are either cut from suitable blocks of carbon, or they may be moulded. It
is, as has hereinbefore been stated, desirable to place them as near as possible to
the free edge of the sonorous bell or vessel.
I may modify the construction as follows, that is to say:-The contact pieces
consist of small pieces of carbon, either of cylindrical or prismatic form. The
arrangement of these carbons upon the sonorous glass vessel may be varied, but
they are preferably arranged in parallel lower rows in which the carbons touch,
and are connected by means of a wire. These rows support intermediate rows of
cylindrical or prismatic carbons; as they rest upon each other by their own weight
they are always regular, that is to say, the vibrations are always produced under
the same conditions, and whatever may be their arrangement or number the
working of the apparatus is the same.
The wooden box, upon which a small Ruhmkorff coil is fixed, carries also a call
or signalling stud or push, a jointed lever which supports the telephone and acts as
a commutator, also a certain number of terminals suitably arranged for establishing
all the necessary electrical connections; a local battery is connected with the
apparatus.
When the telephone is taken from its support, the circuit of the battery is closed
or completed in the following manner, that is to say-The current coming from
the battery passes through a wire to a projection on the box, from there to a
terminal through another wire passing through a piece which by means of a spring
is in contact with the said jointed lever; from the last named terminal the current
passes through the carbons to another terminal, and thence through another wire
to the vibrator of the coil; it then follows the induction wire of the coil, and leaves
it by another terminal to return to the battery through another wire; therefore it
will be seen that when the telephone is removed the current flows to the coil
continuously. The fine or induction wire of the coil forms part of the wire of the
line. On one side the current flows to the station with which correspondence is
carried ou through a wire, and on the other side it goes to earth passing through
the telephone.
When a person speaks before the aforesaid aperture, the sonorous bell or vessel
vibrates. The vibrations are imparted to the carbons and cause variations in the
resistance which the battery current meets with in passing through the whole of
the carbons, and by these variations a series of induced currents is produced in the
fine or induction wire of the coil, which following the main wire of the line go to
and actuate the telephone of the station with which the electro-phone is connected
in such a manner that all the sounds produced in the electro-phone are repeated by
the telephone with which it is, connected.
The sonorous bell or vessel is insulated from the wooden box by wadding, so that
it may not be affected by the vibrations of the wooden box.
For attracting the attention of the receiving station, it is sufficient to press the
button or push herein before mentioned; the telephone resting upon its support
overcomes the tension of the spring, and causes contact between the contact stud

page_text: and the jointed lever. The battery-current then flows through the wires provided,
and consequently the coil is in the requisite condition for operating in the ordinary
manner; the vibrator is thrown into rapid motion, and the induced currents rapidly
repeated in the main-wire act upon the telephone at the station with which
communication is desired. At that station a loud humming sound is then heard,
which is the signal calling attention; the same humming is heard in the telephone
of the sending station. An electric bell is therefore dispensed with, and the action
of the battery is altogether local, which is not the case with ordinary bell-
arrangements, for which batteries (sometimes very powerful ones) are rendered
necessary by the great distance between the stations.
The coil arranged as hereinbefore described, and which can be advantageously
used instead of an electric bell, without necessitating the connection of the stations
by means of a battery, has the further advantage of changing the battery current
into a differential current of high tension, which is produced in the induction wire
of the coil by the variations of intensity of the battery current, consequent upon
the vibrations of the carbons.
The coil I employ may either be an ordinary coil with a soft iron core, or a coil
in which the soft iron is acted upon by a permanent magnet, but I use preferably a
coil in which the soft iron core is replaced by a permanent magnet; this latter
arrangement increases the sensitiveness of the apparatus.
In the modified arrangement above described, the carbons are so connected as to
actually present one single contact piece of great extent.
In the first described arrangement I may employ at will as many contact pieces
of small extent as there are pairs of balls, or all the pairs of balls may be connected,
whereby one contact of a larger surface is obtained; according to the results which
are desired either of the two above named arrangements inay be used, but the
spherical form of the carbons ensures the existence and uniformity of the contact,
so that the apparatus can very easily be regulated.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Harris Lake in the Great Seal Patent Office on the 7th
February 1881.
HENRY HARRIS LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN TELEPHONIC APPARATUS."
A communication from abroad by Louis Maiche, of Paris, France.
<
This Invention relates to improvements in telephonic apparatus or electro-
phones," and is designed for facilitating the transmission of sounds over long
distances.
For this purpose the said apparatus is combined with an ordinary telephone,
which serves as a receiving instrument, repeating at a distance all the sounds that
have acted upon the electrophone. The latter is very sensitive, and is provided
with means for calling the attention of the person at the station or place with
which communication is desired.
This improved apparatus or electrophone consists substantially of carbon contact
pieces imounted upon a bell or sonorous box or vessel of any suitable material
(preferably glass), the said contact-pieces or carbons being placed as near as possible
to the edge of the said bell or sonorous box. These carbon contact pieces transform
the sonorous vibrations of the substance of the bell in front of which the speaking
is carried on into mechanical action, and the said vibrations produce differences of
pressure between the carbons, and consequently variations in the intensity of the
current passing through the said carbons. These variations of intensity produce
induced currents in a coil (say, a Ruhmkorff coil), and these induced currents are
transmitted along the line to actuate the receiving telephone.
By reason of a special arrangement, which dispenses with the necessity for
employing an electric bell, as hereinafter described, my apparatus, together with
its battery and a telephone, form a complete set of mechanism for a station.
In the accompanying Drawing,―
Figure 1 is a vertical section of one form of the said apparatus, and
Figure 2 is a plan of the same.
Figure 3 is a vertical section of a modification of the said apparatus.
Figure 4 is a perspective view, and
Figure 5 is a plan of the same.
Figure 6 shews detached the frame containing the special carbons which I
employ.
A represents a wooden box or case, in which an aperture is made. This box
encloses the bell or sonorous box or vessel C, made preferably of glass. This vessel
is open on one side, and is preferably made with a curved bottom, as shewn in
Figures 2 and 5. The space between the walls of the sonorous vessel and the
wooden box or case A is filled up with wadding or the like. Upon the sonorous
vessel C are placed, one above the other, the contact-pieces made of carbon. These
contact-pieces consist of one or several pairs of carbons a, which are spherical in
form, and which are arranged as near as possible to the edge of the vessel C, and
in such a manner that their position may be regulated upon the end of metallic
rods or stems b, which are hinged at c to the walls of the wooden case or box
enclosing the electrophone, and at these points c two wires 2, 4, terminate; the
current passes through the said stems or rods. One of the carbon balls a, by its
own weight, bears against the sonorous glass bell or vessel, and the other carbon
ball rests upon the first named carbon ball in a like manner. For pressing the
carbons against each other, and against the wall of the glass bell, flat springs may
also be used, though not shewn in the Drawing, and these springs may or may not
be adjustable. The said contact balls are either cut from suitable blocks of carbon

page_text: or they may be moulded; it is, as hereinbefore stated, desirable to place them as
near as possible to the edge of the sonorous bell or vessel.
I may modify the construction of my Invention, as shewn in Figures 3, 4, 5, 6,
that is to say, the contact-pieces may consist of small pieces of carbon R either of
cylindrical or prismatic form, arranged as shewn in Figures 3 and 6, and carried in
a suitable wooden frame.
The arrangement of these carbons upon the sonorous glass vessel may be varied,
but they are preferably arranged, as shown in Figure 6, in parallel rows, in which
the carbons touch, and are connected by means of a wire. These rows support
intermediate rows of cylindrical or prismatic carbons, the carbons being by this
method connected not for tension but for quantity. As they bear upon cach other
by their own weight, they are always properly regulated or adjusted, that is to
say, the vibrations are always produced under the same conditions, and whatever
may be their arrangement or number the working of the apparatus is the same.
The wooden box or case A, upon which a small Ruhmkorff coil E is fixed, carries
also a call or signalling stud or push F and a movable lever G, which supports the
telephone H, and acts as a commutator; it also carries terminals suitably arranged
for establishing all the necessary electrical connections. A local battery is con-
nected with the said apparatus.
When the telephone is removed from its support, the circuit of the battery is
closed or completed in the following manner, that is to say :-The current from
the battery passes through the wire 1 to the piece J, thence to a terminal K²
through the wire 2 passing through the terminal L. The contact between this
terminal and the movable lever G is effected by the spring M. From the terminal K³
the current passes through the carbons to another terminal K³, and thence through
the wire 4 to the vibrator of the coil. It then flows through the induction wire
of the coil, and leaves it by another terminal K, from which it returns to the
battery through the wire 5. Therefore, when the telephone is removed the current
flows into the coil continuously. The fine or induction wire of the coil, shewn in
full lines in the Drawing, forms part of the line wire. From one end of the coil
the current passes to the station with which correspondence is to be carried on
through the wire 6, and from the other end the current goes to earth, passing
through the telephone.
When a person speaks in front of the aperture B the sonorous bell or vessel
vibrates. The vibrations are imparted to the carbons, and produce variations in
the resistance which the battery current meets with in passing through the whole
of the carbons, and by these variations a series of induced currents is produced in
the fine or induction-wire of the coil, which currents following the line wire 6 pass
to and actuate the telephone of the station with which the electrophone is con-
nected in such a manner that all the sounds produced in the electrophone are
repeated by the telephone with which it is connected.
The sonorous bell or vessel is insulated from the wooden box or case by wadding
or the like, as above stated, so that the former may not be affected by the vibrations
of the said box or case.
For attracting the attention of a person at the receiving station it is sufficient to
press the button or push F. The telephone resting upon its support overcomes the
tension of the spring M, and causes contact between the terminal P and the
movable lever G (Figures 1, 2, 3, 4). The battery-current then flows through
the wires 1, 7, 8, and consequently the coil is in the requisite condition for operating
in the ordinary manner. The vibrator is thrown into rapid motion, and the
induced currents rapidly repeated in the main-wire act upon the telephone at the
station with which communication is desired. At this station a loud humming
sound is then heard, which is the signal calling attention. The same humming is
The electric bell is therefore
heard in the telephone of the sending station.
dispensed with, and the action of the battery is altogether local. This is not the
case with ordinary bell-arrangements, for which batteries (sometimes even very
powerful ones) are rendered necessary by the great distance between the stations.

page_text: The coil which is arranged as hereinbefore described, and which as above stated
can be advantageously used instead of an electric bell without necessitating the
connection of the stations by means of a battery, has the further advantage of
changing the battery current into a differential current of high tension, which is
produced in the induction wire of the coil by the variations of intensity of the
battery current consequent upon the vibrations of the carbons.
The coil I employ may either be an ordinary coil with a soft iron core, or a coil
in which the soft iron is acted upon by a permanent magnet, but I use preferably
a coil in which the soft iron core is replaced by a permanent magnet, as the latter
increases the sensitiveness of the apparatus.
In the modified arrangement above described the carbons are so connected as to
actually present a single contact surface of great extent.
In the first described arrangement I obtain as many points of contact of small
extent as there are pairs of balls; or all the pairs of balls may be connected,
whereby one contact surface of a large extent is obtained. According to the
results which are desired, either of these two arrangements may be used, but in
either case the spherical form of the carbons ensures the existance and uniformity
of the contact, so that the apparatus can very easily be regulated.
Having thus fully described the said Invention, as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it under-
stood that I claim,-
First. In a telephonic apparatus or "electrophone" a sonorous bell or vessel of
glass or other suitable material open on one side, and having carbon contact pieces
arranged upon it as near as possible to one of its edges, which contact-pieces
convert into mechanical motion the sonorous vibrations emitted in front of and
received by the bell, substantially as set forth.
Second. In a telephonic apparatus or "electrophone" the carbon contact-pieces
consisting of one or several pairs of carbons of spherical or other form, either
connected with or independent of each other, and placed upon the sonorous glass
vessel, box, or bell of the apparatus, and bearing upon each other and upon the
vessel or box either by their own weight or by the action of springs, which may
or may not be capable of adjustment, all substantially as and for the purposes set
forth.
"
Third. In a telephonic apparatus or electrophone" the carbons arranged in
such a manner that they form a large surface capable of collecting the greatest
possible number of the vibrations of the sonorous vessel.
Fourth. The employment for the purpose specified of a coil, the core of which is
preferably a permanent magnet, and which is properly arranged to produce the
desired effects, as above set forth.
Fifth. In a telephonic apparatus or "electrophone" the arrangement of the coil,
the lever which supports the telephone, a call or signal stud or push, and the
conducting wires in such a manner as will permit the transmission to the receiving
station of a signal, which at the same time is produced at the sending-station.
Sixth. The arrangement of parts herein described, which together form a
telephonic apparatus capable of operating by means of a feeble battery whose
action is purely local.
In witness whereof, I, the said Henry Harris Lake, have hereunto set my
band and seal, this Seventh day of February, in the year of our Lord One
thousand eight hundred and eighty one.