Improvements in Telеpпone Fosts or stations.
Year: 1898

page_text: Improvements in Telеpпone Fosts or stations.
I, PIERRE GERMAIN, of 15bis, Avenue Gambetta, Auxerre, Yonne, in the
French Republic, Telegraphic Engineer, do hereby declare the nature of this
invention to be as follows:
1
The telephonic post or station which forms the subject of the 'present invention
comprises:
10. A transmitter of high voltage currents.
20. A special generator.
30. Two receivers of feeble resistance.
40. A commutator or switch for changing or altering the voltage, the directions
of the current, the grouping or arrangement of the secondary induction circuit.
50. A lightning conductor.
60. A telephonic relay.
TRANSMITTER:
The transmitter is composed of
10. A microphone. 2°. An induction apparatus.
The microphone consists of two similar lozenges or tablets having a circular
shape or form of carbon which has been heated or baked to 3500° in an electric
furnace, and furnished with pyramidical asperities on the working face.
The lozenges or tablets are covered with metal by means of electrolysis, over the
whole of the inactive or non-working surface. The metal deposited should pene-
trate the mass of carbon so as to reduce the electrical resistance of the mass to the
minimum.
It is by a suitable porosity of the carbon that this result is obtained.
Between the two lozenges are arranged a ring and the thin walls of nine cells
of equal surface which are filled with granulated carbon baked at a very high
temperature.
The microphone is thus divided into nine similar small microphones between
the two lozenges.
Whilst one of the lozenges is incorporated or formed with the ring the other can
move thereto in the direction of the axis of the figure.

page_text: This latter is screwed to a rigid cross formed in aluminium, the four arms of
which are ended by small clasps or hooks.
These hooks serve to fix or attach on the one side four small fixed spiral springs
at the other side by four aluminium hooks fixed or lodged in the mica ring.
The recess intended to receive the granulated carbon contained between the
mica walls is so calibrated that on putting therein the same quantity, as regards
volume and weight, of granulated carbon the grains being of the same shape and
size, the springs being equal, the mounting of the microphone is performed with-
out regulation or adjustment and all adjustment is thereafter useless or by the
following.
The intakers or receivers of current formed of refined and twisted copper wires
have or offer no appreciable resistance.
They are covered with a layer at the base of calcareous silicate which prevents
metallic vibrations and indefinitely retains its properties, in spite of the eventual
or accidental action of heat.
They are joined together by an end or extremity on each lozenge, which at the
centre carries or is furnished with a cylindrical shoulder projecting for about
3 millimetres.
At the middle of this shoulder is arranged a hole where is fixed by a lock or
key the furrows or channels of the screws which serve to connect or bind the
microphone to the vibrating membrane or diaphragm and to the aluminium
cross.
The whole is arranged so that the electrical resistance remains or is almost
exclusively in the interval or space known as the "working space" occupied by
the granulated carbon.
By a delivery or exercise of the microphonic current suitably regulated, a slight
warming scarcely exceeding 35° Centigrade, is produced in the mass of the
granulated carbon.
The small quantity of heat developed has a double and favourable effect with-
out altering the properties of the substances or parts forming the microphone.
1°. The active resistance is reduced to the minimum with the minimum of
dead weight.
2°. The warming avoids or disperses dampness so harmful to or in microphonic
effects or purposes.
Small holes are arranged for this purpose in the ring in mica.
It is so important that the state of perfect dryness of the air surrounding the
active granular mass should be maintained that to complete it a small dessicating
tube is placed within a closed case or chamber, the vibrating diaphragm of which
forms one of the sides.
This tube is of about 10 millimetres diameter and 300 millimetres length and
is wound spirally and fixed by a cross piece to screws to one of the sides of the
closed chamber. It is made of linen or canvas or similar suitable material a little
pierced or perforated and filled with a fine beaten powder of absorbent cellulose
and of dry magnesium powder.
The proportion by volume of these two products should be such that the whole
of the magnesium chloride can fall into deliquescence or become deliquescent
without a drop of liquid oozing or leaking out of the perforated tube.
The vibrating diaphragm is of glass or wood with a metal portion in the centre.
It is retained on the rebate of the cover or lid of the wooden box by means of
a metallic frame and four metal screws.
Between the flange of the diaphragm and of the rebate of the lid, is interposed
a band or ring of soft rubber. An inflexible wall with an opening at the middle
protects the vibrating membrane against damage from the exterior.
The intakes or receivers of the current are screwed to the sides of the lid and
are put into communication with the socket or base of the box by means of a set
screw or other similar device.

page_text: That the induction apparatus may suit equally well, telephony on overhead,
underground or submarine systems, the relation between the resistance of the
primary circuit and the secondary circuit is fixed at
0.50
12.50
ohm.
In spite of the considerable reduction in the resistance relatively to the induction
coils in use, the number of turns of the wire or coil of the two circuits is
maintained.
To attain this result in practice I either use several similar induction coils
which are grouped or arranged in such a manner as to have the relation
or,
0.50
12.500hm
I take a single coil with multiple wires for quantity, for the secondary circuit
as for the primary circuit.
0.50
12'50
The single coil whilst bearing or presenting the proportion of- ohm should
also have as many wires for quantity as 6 bobbins small shape of the relation
1.50
ohm.
150'
0'75
When one is not limited by the site or place in or of the post or by the cost,
it is preferable to choose the use of distinct coils (small shape) having a double
wire for quantity which gives for the proportion or relation of each coil
The secondary circuit of the 6 coils is grouped or arranged for quantity and
the primary circuit in the following manner:-
75 ohm
Two equal series or sets of three coils arranged for quantity, the two sets or
series being afterwards arranged in tension.
When on the other hand, the questions of site or position and of price are taken
into consideration, I use a single coil having six coils or wires for quantity for
the secondary current and having 3 wires for the primary circuit.
Whatever be the type of coil used, between the two circuits is placed a third
circuit wound in the same direction; this circuit is called the separator or ternary
circuit.
It possesses a resistance three times greater than that of the primary circuit.
It is closed upon itself and plays or acts a favourable part set out hereafter.
This circuit should be composed of a wire well insulated. It thus dispenses
with an insulating tissue or wrapper which is usually passed between the primary
and secondary circuits.
MICROPHONIC GENERATOR.
A generator consisting for example, in the Administration Française of the
three Leclanché elements or of the three LaLande elements or the two elements
of the Block battery, is sufficient to actuate or work the microphone above described,
when it is simply a question of communicating between urban and interurban
stations such as those now in service but when providing for long distance tele-
phony, subterranean or submarine cables, a more powerful generator is necessary.
It consists in the whole :-
10. Of two elements of the Block battery in tension, for the charge.
20. Of 7 or 8 small secondary elements.
30. Of a multiple commutator for charging and discharging.
Among the batteries mentioned above, the Block battery alone suits the charg-
ing, as to voltage, capacity, output, facility of setting up near the post, dispensing
with maintenance.
This charge battery only works when the microphone is at rest; the battery
can also have or give rise to a more or less irregular output, even polarisation,
without altering the work of the microphone.
-

page_text: These latter should be placed as near as possible to the telephonic post so as
to reduce to a minimum the resistance of the auxiliary wires.
Each element of the secondary battery consists of a small receiver in the shape
of a strengthened and hardened glass gauge, of a small positive plate and of a
small negative plate both lengthened and narrowed, and finally of a button or
plug of rubber.
This latter is perforated at intervals with 5 holes gauged and parallel.
Each plate is furnished upwardly with two cylindrical supporting rods of metal
of which they are extensions. One of these rods forms the intake or receiver of
the current; these two plates are held parallel at a suitable distance and are
3 centimetres from the bottom.
In the traverse or passage of the fluid no solid body touches them at any
point of contact. This is one of the essential conditions to the preservation of
the charge.
The fifth hole is stopped by a small glass tube surmounted by a soft and thin
rubber cap pierced with a pin hole.
Gas and vapours can pass thereto under pressure without the fluid communicat-
ing with the outer air. Each receiver is filled with acidulated water to the upper
part of the plates. All the elements of the same battery are placed in a single
row so that the verification or the ascertaining of the level of the liquid and of the
separation of the plates can be instantly made.
The intakes or receivers of the current join or are attached to the multiple
charging commutator by thick and short flexible wires, which commutator only
differs from those now known, in the following particular respects: -
All parts are of good conducting copper, and the springs press very firmly so
that the current passing through the apparatus meets with no appreciable amount
of resistance.
This commutator is worked by a suitable handle.
When at rest, all the secondary elements are charged for quantity, whilst in
the working position, they are ready to be discharged in tension across the primary
circuit. A second combination can be employed for the automatic charging and
discharging.
The commutator, in this case, is actuated by the hook commutator by means of
a bevel gear.
When the receiver is taken down or unhooked the secondary elements are put
into series for discharging.
When the receiver is hooked on or replaced, the elements are put into quantity
for the charging.
A resistance which can be varied within certain limits is interposed between
the battery and the commutator. This should be sufficient that the output at the
charge does not exceed the degree which would correspond with or entail the
polarisation of the battery.
It ought not to impede the output more than to the point at which it would
be insufficient for the capacity of the secondary elements.
By the working of the multiple charge commutator, an important operation is
automatically performed at the same time, which is, the inversion of the micro-
phonic current, that is to say, that I avail myself sometimes of the positive current
and sometimes of the negative current.
This change effected at intervals or periods of 24 hours or at the duration of or
after a conversation is very favorable to the preservation of the granulated
carbon of the microphone, especially with currents of a high voltage as those
necessary for the working of the apparatus described.
There is, in reality, produced in time, a modification in the surface of the
granules. Their conductibility changes with their sensibility from the point of
view of variations of resistance arising from differences in pressure.
Two large conductors having fine copper wires, arranged in the shape of a cord,
connect the multiple changing commutator to the two parts of the primary circuit.
5

page_text: or filaments opposed two and two, an infinitesimal distance separating them and
preventing the telephonic currents from passing.
Atmospheric discharges take place a dozen times more easily than in lightning
conductors at present used.
This single apparatus may be replaced by a certain number of small incan-
descence lamps of 3 to 4 volts previously burned by the current and arranged
or grouped for quantity.
RELAYS.
To increase the extent of the telephone, which is limited by too numerous
difficulties on long systems, I complete, the material of the post or station by
a translator relay of vibratory currents, which can be placed at the most favour-
able point for the circuits to be served.
This relay comprises,
10. An iron magnet consisting of a compound magnet or bundle of pencils.
20. An electromagnet with two short coils.
3°. Other essential parts.
The magnet is of steel of extra quality, magnetised by the best known methods.
At the end of one of the two arms are screwed two cores of iron, chemically pure.
These cores are each 15 millimetres diameter and 15 millimetres long.
Brass or latten cheeks are joined to the ends.
The wire directly wound around the cores is of copper of a very high con-
ductibility and well insulated.
It has three ends.
The resistance, according to the length of the circuits served, is of 50, 100 or
150 ohms.
The polar extremity of the iron core is well trimmed, finished and polished or
burnished. A thin disc of carbon covered by electrolysis with a layer of pure
bright iron, fits exactly to the polar portion and is incorporated both electrically
and magnetically therewith.
A ring of mica is formed around.
In the cavity or recess formed by this ring is introduced a certain quantity
of granulated carbon with which has been incorporated iron chemically pure.
The outer portion of the granulate is of carbon the interior of iron. A carbon
lozenge granulated or roughened on its working face, closes the cavity or recess
filled with granulate.
This lozenge placed parallel to the polar surface covered with carbon. It
is coated with copper over the whole of its inactive surface.
At its rearward centre is fixed a regulating screw. This screw is supported by
a guard.
The microphonic current arrives on the one side at the guard of the regulating
screw; on the other side at the mass formed by the magnet and the electro-magnet.
At the centre of gravity of the mass, and by the help of two pivots and their
supports, the whole arrangement can be turned in view of setting at different
inclinations by method of regulation by hand-screw, the granulate and that
which surrounds it.
The supports are fixed to a socket or base of wood furnished underneath with
soft rubber.
To the base or socket are attached four terminals.
Two similar relays are united or connected on the same base with eight ter-
minals in all.
The secondary circuits of the two relays are in shunt on the two sections of the
circuit served.
The granulate is traversed by a microphonic current as that produced by the
system of generator above described. This current circulates in the primary
circuit of one induction coil, the secondary circuit of which is in shunt on the line
circuit.
3

page_text: The two relays work at once.
The result is that the current from the post or station whence one is speaking,
is bifurcated into the two relays, (secondary circuits) which send at the same time
two local currents in the primary current. The sensibility of this relay proceeds
from, notably, the high voltage and close proximity of the granulate armature of
the active surfaces of the polarized electro-magnet. A special commutator allows
the intensity of the microphonic current from the telephonic post to be reduced
when the excess betrays itself by sparkings on the short circuits.
ADVANTAGES.
The special baking of the carbon of the microphone increases the conductibility
and diminishes sparkings. The metallization of the carbon reduces to a minimum
the electrical resistance and distributes the developed heat over the whole at the
same time.
The porosity of the carbon allows the solution of the copper of electrolysis to
penetrate it and reduces the resistance of the carbon mass.
The sub-division of the microphone into a certain number of similar and dis-
tinctive parts, has for effect to reduce the intensity of the sparkings by excess
of voltage, without necessitating the use of compressed granulate which would
greatly reduce the sensibility of the contact, known as telephonic.
The microphone is mounted or set up in such a manner as not to necessitate
regulation on the part of the constructer, by which I mean to no greater an extent
than agents charged with this after maintenance.
The resistance of the connections of the primary circuit and of all parts of the
microphone is considerably reduced and the bearing rendered more powerful or
intense by the almost total suppression of the interior resistance of the secondary
elements, by the reduction to a third of the resistance of the primary circuit of
the induction coil, by the diminution of the length and the increase in section of
all the auxiliary wires, by the jointing of the metal of the lozenge of the two
intakes or receivers of the microphone's current.
The warming or heating of the granulate and of the lozenges of the micro-
phone increases the conductibility of the carbon and dries the surrounding air.
The effect of dessication of the tube full of magnesium chloride or of a similar
product and of absorbing cellulose powder, ensures a constant state of dryness to
the vibrating diaphragm or membrane, to the carbon and to the air surrounding
the granulate.
The induction coil introduces a very feeble resistance in the circuit.
The third circuit, called, separator, closed on itself, favourably influences self-
induction and affords undulatory circuits of a quality superior to those of other
systems.
The primary circuit, and the secondary circuit induce or act by induction on
the third circuit which, in its turn, induces on them.
The generator has a very feeble interior resistance. It has displaceable energy
one hundred times greater than that of the primary batteries other than the Block
battery.
The recharge practically effects itself.
The call generator and the call magnets are economically replaced by the second
battery.
The suppression of the source of the charge is made automatically, thanks to
the coincidence of the voltages. The call push or handle can be dispensed with,
as also the operation required therefor.
The inversion or change of the microphonic current which takes place auto-
matically has for advantages the preservation of the properties of the constituent
parts of the microphone. the diminishing of the harmful effect known as settling
or sinking of the granulate.
The receivers are very powerful whilst bearing in the circuit for each post or
station a resistance about eight times less than other systems.

page_text: If there be caused to intervene the difference of resistance of the secondary
circuit of the inducing coil, it will be found that the resistance of the apparatus
of the two posts or stations of any one circuit, not including the resistance from
self induction is 10 times less in the Germain post or station than in other
systems.
The combination of the second breaker-hook allows of concentrating the whole
action of the current on the single unhooked receiver.
The production of current in quantity on the secondary circuit where the
apparatus of the post have a very feeble resistance, is very suitable and convenient
for communication on badly insulated circuits, on cables with graduated shunts
and on all circuits of reduced resistance by graduated derivations.
The relay allows of other sections being added to the limit sections on which
correspondence takes place with ordinary apparatus. It allows important under-
ground sections being added to the longest overhead lines along which com-
munication now takes place, and even communication along lengthy underground
or submarine circuits.
The use of relays at each end of the circuit joining the central bureaux would
allow all conversations to be improved or intensified on all systems independently
of the value of the different systems of subscribers.
Finally the use of currents for quantity, having a feeble voltage on long circuits
affected by simultaneous telegraphy and telephony, as well as the sectioning of
these circuits and the use of intermediary relays, improve the hearing and tele-
graphic transmissions.
Improvements in Telephone Posts or Stations.
I, PIERRE GERMAIN, of 15bis, Avenue Gambetta, Auxerre, Yonne, in the
French Republic, Telegraphic Engineer, do hereby declare the nature of this
invention 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 telephone post or station for overhead, underground
and submarine telephone-wire systems.
The telephonic post or station which forms the subject of the present invention
comprises:―
1º. A transmitter of high voltage currents.
20. A special generator.
3. Two receivers of feeble resistance.
4°. A commutator or switch for changing or altering the voltage, the directions
of the current, the grouping or arrangement of the secondary induction circuit.
50. A lightning arrester.
6°. A telephonic relay.
Upon the drawings annexed to this specification,
Figure 1 represents in sectional elevation one type of transmitter used in my
telephonic station.
Figure 2 illustrates another type of transmitter.
Figure 2 shews on an enlarged scale one of the smaller combined diaphragms.

page_text: The transmitter is composed of
1°. A microphone. 20. An induction apparatus.
The microphone Fig. 1, consists of two similar lozenges or tablets A A¹, having
a circular shape or form, of carbon which has been heated or baked to 3500° Centi-
grade in an electric furnace and furnished with pyramidical asperities on the
working faces a.
These lozenges or tablets are covered with metal by means of electrolysis, over
the whole of the inactive or non-working surface a°. The metal deposited should
penetrate the mass of carbon very deeply so as to reduce the electrical resistance
of the mass to the minimum.
It is by a suitable porosity of the carbon that this result is obtained.
Between the two lozenges are arranged a mica ring a¹ and the thin mica walls
of nine cells a² of equal surface which are filled with granulated carbon baked
at a very high temperature. Mica or other suitable insulating material may be
used for the ring and walls.
The microphone is thus divided into nine similar small microphones between
the two lozenges.
On the annexed drawing there are only eight cells or compartments shewn.
Whilst one of the lozenges A is incorporated or formed with the mica ring the
other A¹ can move towards the former in the direction of the axis xx.
This lozenge A is screwed to a rigid cross formed in aluminium a³, the four
arms of which are ended by small clasps or hooks.
These hooks serve to fix or attach on the one side four small spiral springs a
fixed at the other side by four aluminium hooks secured permanently to the mica
ring and the lozenge A.
The recess intended to receive the granulated carbon contained between the mica
walls is so calibrated that on putting therein the same quantity, as regards
volume and weight, of granulated carbon, the grains being of the same shape
and size and the springs being equal,-the mounting of the microphone is per-
formed without regulation or adjustment and all adjustment is thereafter useless.
The intakers or receivers of current formed of refined and twisted copper wires
have or offer no appreciable resistance.
They are covered with a layer or plaster having a calcareous silicate base which
prevents metallic vibrations and indefinitely retains its properties, in spite of the
eventual action of heat.
They are joined together by an end or extremity on each lozenge, which at the
centre carries or is furnished with a boss or cylindrical shoulder as projecting for
about 3 millimètres.

page_text: At the middle of this shoulder a hole is provided in which are fixed by a lock-
ing device the screws or bolts which serve to connect the microphone to the
vibrating membrane or diaphragm B and to the aluminium cross.
The whole is arranged so that the electrical resistance remains or is almost
exclusively in the interval or space known as the "working space" occupied by
the granulated carbon.
By a suitably regulated admission of the microphonic current, a slight heating,
scarcely exceeding 35° Centigrade, is produced in the mass of the granulated
carbon.
The small quantity of heat developed has a doubly favourable effect without
altering the properties of the substances forming the microphone.
1°. The active resistance is reduced to the minimum with the minimum of
dead weight.
20. The heating avoids or disperses dampness so harmful to microphonic effects.
Small holes are arranged for this purpose in the mica ring.
It is so important that a state of perfect dryness of the air surrounding the
active granular mass should be maintained that to complete it a small dessicating
tube is placed within a closed case or chamber, one of the sides of which is formed
by the vibrating diaphragm.
This tube is about 10 millimetres diameter and 300 millimetres length, and
is wound spirally and fixed by a cross piece to screws to one of the sides of the
closed chamber. It is made of linen or canvas or similar suitable material
pierced or perforated to some small extent and filled with a fine ground powder
of absorbent cellulose and of dry magnesium chloride.
The proportion by volume of these two products should be such that the whole
of the magnesium chloride can deliquesce without a drop of liquid oozing or leak-
ing out of the perforated tube. A suitable proportion of these components will
be 30% of cellulose and 70% of chloride.
The vibrating diaphragm B is of glass or wood with a metal portion b in the
centre.
It is retained on the rebate of the cover or lid of the wooden box by means of
a metallic frame and four metal screws.
Between the flange of the diaphragm and of the rebate of the lid, is interposed
a band or ring of soft rubber. An inflexible wall with an opening at the middle
protects the vibrating membrane against exterior damage.
The intakes or receivers of the current are screwed to the sides of the lid and
are put into communication with the socket or base of the box by means of a set
screw or other similar device.
I will now refer to the transmitter illustrated on Figures 2 and 2^.
The vibrating plate of the post's transmitter consists of a certain number of
similar diaphragms or membranes R of specially thin and carefully made glass,
having a thickness of 12 to 18 hundredths of a millimetre and of a diameter of 6
to 8 centimetres; these dimensions are the average, but can be varied. The
mass of the dead weight of the microphones is divided between the centres of all
the diaphragms.
Between each vibrating diaphragm is an inflexible wall which is placed above,
under the form of an air-tight lid r or constitutes an air-chamber furnished with
a small outlet r³, see Figure 2ª, to allow damp air or condensed water to escape.
The various air chambers of the same apparatus communicate with a single
opening or mouth-piece S by means of separate tubes s.
The mouthpiece is of a small or large shape according as it is wished to tele-
phone in a loud or in a low voice.
Each part of the microphone thus subdivided into several vibrating glass
diaphragms, consists of,
10. Two similar lozenges T T, of carbon coppered or coated with copper on their
inctive faces and having asperities on their active faces.
20. A thin and soft rubber tube or wrapper t in which perforations have been

page_text: made, at slight distances apart; at the end of or outside the tube is wound a
spiral of small thread to cover or stop the openings by which the too fine
granulate would escape, which latter is placed at, without, however, reducing
the elasticity of the whole.
30. Granulated carbon prepared or baked in an electrical furnace, the same as
the lozenges above specified and in the manner already explained.
4°. Intakers or receivers of the current which are very flexible and of copper,
jointed to the copper deposited on the lozenges.
This transmitter having a plurality of membranes or diaphragms formed of
thin glass, the action of which is united or connected to a single outlet, presents
a great neatness combined with great sensitiveness.
INDUCTION APPARATUS.
In order that the induction apparatus may suit telephony equally well on
overhead, underground or submarine systems, the relation between the resistance
of the primary circuit and the secondary circuit is fixed at ohm.
0.50
12.50
In spite of the considerable reduction in the resistance relatively to the
induction coils in use, the number of turns of the wire or winding of the coil of
the two circuits is maintained.
To attain this result in a practical manner I either use several similar induction
coils which are grouped or arranged in such a manner as to have the relation
00 ohm. or, I take a single coil with multiple wires for quantity, for the
12.50
secondary circuit as for the primary circuit.
0.50
150
(-50
12:0
The single coil whilst bearing or presenting the proportion of ohm. must
have as many wires for quantity as 6 coils small shape of the proportion or
relation ohm. This will easily be understood. Suppose that in a coil of
150 ohms. there are 3000 turns of single wire, if this number of 3000 turns be main-
tained, and that nevertheless, it is wished to have only 12.50 ohms. resistance,
wire composed of 12 similar twists will be put in quantity. As a matter of fact,
there are two expressions; the number of turns and the resistance; if it is not
wished to have the number of turns changed, so as to have 12 times less resistance,
it will be necessary to group or arrange the wire in quantity.
When one is not limited by the site or place in or of the post or by the cost,
it is preferable to choose the use of distinct coils (small shape) having a double
0-75
wire for quantity, which gives for the proportion of relation of each coil 7
ohm.
The secondary circuit K¹ of the 6 coils is grouped or arranged for quantity,
and the primary circuit k is arranged in the following manner, see Figure 6:
Two equal sets or series of three coils arranged for quantity, the two sets or
series being afterwards arranged in tension. The transmitter shewn diagram-
matically at J is interposed upon the primary circuit.
When on the other hand, the questions of site or position and of price are
taken into consideration, I use a single coil having six coils of wires for quantity
for the secondary circuit and having 3 wires for the primary circuit.
Whatever be the type of coil used, between the two circuits is placed a third
circuit wound in the same direction; this circuit is termed the separator or ternary
circuit.
It possesses a resistance three times greater than that of the primary circuit.
It is closed upon itself and plays or acts a favourable part set out hereafter.
This circuit shewn diagrammatically by k on Figure 6 of the drawing, should
be composed of a wire well insulated. It thus dispenses with an insulating
tissue or wrapper which is usually passed between the primary and secondary
circuits.

page_text: MICROPHONIC GENERATOR.
A generator consisting for example, in the Administration Francaise of the
three Leclanché elements or of the three Lalande elements or the two elements
of the Block battery, is sufficient to actuate or work the microphone above
described, when it is simply a question of communicating between urban and
interurban stations such as those now in service, but when providing for long
distance telephony, subterranean or submarine cables, a more powerful generator
is necessary.
It consists in the whole :-
1º. Of two elements of the Block battery in tension, for the charge.
20. Of seven or eight small secondary elements, forming the line battery.
A multiple commutator allows the secondary elements to be coupled in quantity
for charging and in tension for discharging; also, it automatically effects the
reversal of the discharge current on the microphone; this commutator is operated
or manipulated automatically by the one of the hooks or claws supporting a
receiver.
This battery is put in charge on the accumulators only when the microphone
is at rest, at night for example. The battery can also have or give rise to a dis-
charge more or less irregular, even polarisation without altering the work of the
microphone.
These latter or the accumulators should be placed as near as possible to the
telephonic station so as to reduce to a minimum the resistance of the auxiliary
wires.
The way I arrange the accumulators allows them to be placed very near the
station.
Each element of the secondary battery consists of a small receiver C, see
Figure 3, in the shape of a strengthened and hardened glass gauge, of a small
positive plate e and of a small negative plate c¹, both being elongated and narrowed,
and finally of a rubber plug c².
This latter is perforated at intervals with 5 gauged and parallel holes.
Each plate is furnished at or towards its upper portion with two cylindrical
and metal supporting rods, of which they are the extension. One of these rods
forms the intake or receiver of the current; the two plates are held parallel at
a suitable distance and are 3 centimetres from the bottom. .
In the traverse or passage of the fluid no solid body touches them at any
point of contact. This is one of the conditions essential to the preservation of
the charge.
The fifth hole is fitted with a small glass tube
rubber cap pierced with a pin hole.
surmounted by a soft and thin
Gas and vapours can pass therethrough under pressure without the fluid com-
municating with the outer air. Each receiver is filled with acidulated water to
the level of the upper part of the plates. All the elements of the same battery
are placed in a single row so that the verification or the ascertaining of the level
of the liquid and of the separation of the plates can be instantly made.
The receivers of the current are joined or attached to the multiple charging
commutator by short thick wires.
This commutater is automatically controlled by one of the hooks or claw-arms
supporting the receivers in such a manner that when the receiver is hooked up,
the primary battery is put in charge on the secondary battery coupled for
quantity, and that when the receiver is unhooked, the primary battery is insulated
or cut off from the secondary battery and this latter placed in tension is put on
the microphone; further, this commutator is arranged so that the current directed
on the microphone changes direction each time it is used; this inversion or
reversal is very favorable to the preservation of the microphone's granulate.
especially with high voltage currents such as those necessitated by the working
of the apparatus described. There is, in reality produced in time a modification

page_text: or change in the surface of the granules. Their conductivity changes in the same
manner as their sensitiveness from the point of view of the resistance variations
provoked by differences in mechanical pressure.
This reversing commutator is shewn on Figures 9 to 14 inclusive. It consists of
a cylinder of insulating material furnished on two successive generatrices
according to perpendicular planes, with the following contacts;-two bars or
strips end to end on the same generatrice and a series of contacts on the
other generatrice in number double to that of the secondary elements to be
coupled up; if there are four elements, there are eight contacts, four of which
in succession are affected by poles of the same denomination and the remaining
four by the second poles of the secondary elements. On the same circumferences
as those of these contacts are arranged two series or sets of eight springs 2-3 7-3
. . making contact with the cylinder V on two generatrices at the ends of one
diameter; the two groups of four springs corresponding to the circles of four
successive contacts
are connected to the secondary battery in such a
manner that two springs on the same circle are connected to the positive pole of
the first element and the two following springs to the positive pole of the second
element, as for the four groups or sets of two.
The four remaining sets of two springs are connected to the second poles of the
elements. The eight contacts el r
of the cylinder are connected together in
such a manner as to couple in tension the secondary elements when they are in
contact with one or the other of the two sets of springs ³ ³ The two poles
of this coupling up in tension abut against the two contacts 22 22 on the same line.
as the contacts and which can make contacts with two springs by which
means the battery is put in circuit on the various apparatus. As to the bars ev,
they communicate with two metallic circles on which constantly bear two con-.
tacts connected to the charge battery. The two springs are repeated or
duplicated at the opposite end of one diameter and they are connected in such a
manner that the opposite springs communicate not with the same wire but one
with the first wire and the other with the second wire. With such an arrange-
ment, it will be seen that when the line of the bars vv is in contact with one or
the other set of springs, the primary battery is put in charge upon the
accumulators coupled for quantity.
When the line of the contacts 1 and 2 communicates with the springs and
respectively, the battery is no longer in charge upon the accumulators and these
are coupled in tension, but according as the line of contacts is on one side or the
other of a diameter, the current is sent in one direction or in the other through
the apparatus. I thus obtain, if the cylinder rotates by quarter turns always in
the same direction-charge-discharge, first direction-charge-discharge, second
direction-charge-discharge, first direction-charge-etc. etc.
This manipulation is automatically effected by means of one of the receiver
hooks, connected to the cylinder by any suitable mechanism which will cause the
latter to make a quarter-turn whether the receiver-hook be raised or lowered.
For this purpose the cylinder V is controlled by a lever Y fulcrumed at y, see
Figs. 9 and 12, and acting by means of two levers or rods y' y' on two toothed
segments which engage with and actuate two toothed wheels y y placed
side by side being thus able to rotate the axis of the commutator by means of
pawls y; with this arrangement, after the ascent of the hook or claw arm drawn
up by means of a spring y, when the receiver is unhooked the commutator makes
a quarter-turn discharging the battery in the first direction, when lowered it
makes a quarter turn putting the battery in charge; at the time of raising the
same it discharges the battery in the second direction, and then when lowered, in
charge, after a subsequent rise, in discharge, first direction, and so on.
A small notched wheel y Figures 9 and 14, fixes the cylinder in each of its
positions.
A resistance which can be varied within certain restricted limits is interposed
between the battery and the commutator. This should be to such an extent

page_text: sufficient that the output at the charge does not exceed the degree which would
correspond with or entail the polarisation of the battery.
It ought not to impede the output more than to the point at which it would be
insufficient for the capacity of the secondary elements.
Two large conductors having fine copper wires, arranged in the shape of a cord,
connect the multiple charging commutator to the two parts of the primary circuit.
This cord directly enters the interior of the box. There remains no bare com-
munication belonging to the primary circuit. All the usual visible terminals,
which may give rise to short circuits accidentally, are dispensed with.
The connections are arranged interiorly in such a manner that the accumulators
cannot be accidentally discharged, by placing a piece of metal in contact with
exterior terminals.
RECEIVERS.
The receiver, Figure 7, consists of a powerful magnet in the shape of a ball-
handle or of four rings superposed in the interior of the box.
The soft iron of the electro-magnet and of the armature is chemically pure.
The cores are flat, elongated and very much drawn inwards or together from
the centre.
The resistance of the two coils is reduced to a quarter by the bifurcation of the
current, that is to say the two coils are arranged for quantity.
The two receivers are also arranged for quantity. Their resistance is 37.5 ohms.
The box is elongated according to the length of the coils. It is surrounded
by soft rubber. The lid which is screwed on the box is of soft iron.
The cable which connects the two terminals of a receiver to a station or post
box is of ordinary length and consists of 2 flexible copper conductors of a very
feeble resistance.
The two receivers of a station are grouped or arranged for quantity in such a
fashion that the one which is not unhooked remains out of circuit and the current
which would otherwise have actuated or excited it in sheer loss, or as a pure waste
of current, as does take place in systems at present used, is concentrated on the
single receiver employed.
To obtain this result the second hook is lightly movable on its axis, see Figure 8.
The circuit is bifurcated on to the two receivers, it goes directly to the receiver
which must always to be unhooked at the time of a conversation and which is
that one operating or manipulating the reverser-commutator (it will be remarked
that, in addition, the hook of this commutator will put, as ordinarily, the line
either on the bell or on the receiver in the usual manner; that is completely
beyond the reverser-commutator and it is useless to shew it on the drawing).
As for the other receiver, it is put in circuit only when it is unhooked; in this
way, if one receiver be used by the listener, the current is not sent uselessly into
the second.
There is thus produced an interruption of circuit in the receiver by hooking or
hanging up.
GRADUATED DERIVATIONS OR SHUNT
The arrangements carried out in this telephonic post or station are especially
of a nature to afford strong currents, which gives it a marked superiority on long
circuits badly insulated for all weathers, and in which shunts or losses (leakages)
may be produced.
CALLS.
The current from the generator is powerful enough to allow "calls" to be made
automatically by the fact of unhooking the receiver or simply by the raising of
the commutator hook.
66
This method of automatic call" which is effected without the help or the
actuating of keys or pushes may optionally be replaced by the use of the con-
tinuous microphonic current of the secondary battery operated and controlled by
any suitable push. It may be made by ringing, if so desired, in the ordinary

page_text: call or receiver.
The post or station-box otherwise presents no special features beyond an almost
air-tight case or chamber, whose microphone's vibrating membrane or diaphragm
forms one of its sides.
This case or chamber is affected by the action of the dessicating tube.
LIGHTNING ARRESTER.
The lightning arrester is composed of a glass globe in which has been formed
a vacuum. Within this are placed several small carbon filaments as used for
incandescence lamps.
These filaments are connected exteriorly to the metallic contacts or receivers
of the curient, arranged for quantity. They are burned by the passage of a
current having a graduated intensity.
There remains then in the glass globe an equal number of earth and line wires
or filaments opposed two and two, an infinitesimal distance separating them and
preventing the telephonic currents from passing.
Atmospheric discharges take place a dozen times more easily than in lightning
ariesters at present used.
This single apparatus may be replaced by a certain number of small incandes-
cence lamps ww. . . . of 3 to 4 volts, Fig. 15, previously burned by the current
and arranged or grouped for quantity on the line wires; the two sets of filaments
not connected with the line are continued to earth.
دو
RELAYS.
To increase the " carry or extent of the telephone, which is limited by too
numerous difficulties on long systems, I complete the elements of the post or
station by a translator relay of vibratory currents, which can be placed at the
most favourable point for the circuit to be served.
This relay comprises,
10. A horseshoe magnet D consisting of a compound magnet, or built up
magnet.
20. An electro-magnet with two short coils.
30. Other essential parts.
The magnet is of steel of extra-magnetised quality obtained by the best known
methods. At the end of one of the two arms are screwed two cores d of iron,
chemically pure. These cores may each be 15 millimetres diameter, and 15 milli-
metres long, which are suitable dimensions.
Brass or latten cheeks are joined to the ends.
The cable & directly wound around the cores is of copper of a very high con-
ductivity and well insulated.
This cable is formed of 3 insulated wires, connected together at their
extremities so as to increase the number of turns or windings without increasing
the resistance.
The resistance, according to the length of the circuits served, is of 50, 100 or
150 ohms.
The polar extremity of the iron core is well trimmed, finished and polished.
A thin disc of carbon d² covered by means of electrolysis with a layer of pure
bright iron exactly fits the polar portion and is incorporated both electrically
and magnetically therewith.
A ring of mica is secured around.
In the cavity or recess formed by this ring is introduced a certain quantity of
granulated carbon with which has been incorporated iron chemically pure.
The outer portion of the granulate is of carbon, the interior of iron. A carbon
lozenge granulated or roughened on its working face, closes the cavity or recess
filled with the granulate.

page_text: This lozenge is placed parallel to the polar surface covered with carbon. It is
coated with copper over the whole of its inactive surface.
At its rearward centre is fixed a regulating screw d. This screw is supported
by a bridge or guard.
The microphonic current arrives on the one side at the guard of the regulating
screw on the other side at the mass formed by the magnet and the electro-
magnet.
At the centre of gravity of the mass, and by the help of two pivots and their
supports, the whole arrangement can be turned in view of setting up at different
inclinations by a regulating method by means of a hand-screw or otherwise, the
granulate and that which surrounds it, see Figure 4*.
The supports are fixed to a wooden socket or base furnished underneath with
soft rubber.
To the base or socket are attached four terminals.
Two similar relays are united or connected on the same base with eight ter-
minals in all.
The secondary circuits of the two relays are in tension on the two sections of
the circuit served.
The granulate is traversed by a microphonic current such as that produced by
the system of generator above described. This current circulates in the primary
circuit of one induction coil, the secondary circuit of which is in shunt on the
line circuit.
The two relays work at once.
The result is that the current from the post or station whence one is speaking,
is bifurcated into the two relays (secondary circuits) which send at the same time
two local currents in the primary circuit. The sensitiveness of this relay pro-
ceeds from, notably, the high voltage and close proximity of the granulate coat-
ing of the active surface of the polarized electro-magnet. A special commutator
allows the intensity of the microphonic current from the telephonic post to be
reduced when the excess betrays itself by sparkings on the short circuits.
Figure 5 shews the erection of a relay. E E, E E¹ are the line wires, of arrival
and departure. F F are the two telephonic relays such as above described. ggare
automatic key-tappers or interrupters of the local primary circuits G G. HH'are
the inductors of the two induction coils, and I I' are the armatures. The setting
up of the relay station is easily understood from an inspection of the figure.
If station No. 1, see Figure 5, speaks, the current passes in the coils of the
relay (passing along the secondary circuit 1): this relay F works and sends
the current from the local battery modified by its microphonic part, to the
primary circuit H'; this latter acts by induction on the secondary circuit I' and
the relay current passes along the line E (passing by way of the coils of relay F¹.
If station No. 2 speaks, the current passes in the same manner, but the side of
relay playing the part of the relay F as has just been explained, and inversely.
ADVANTAGES.
The special baking of the carbon of the microphone increases the conductibility
and diminishes sparkings.
The metallization of the carbon reduces to a minimum the electrical resistance
and distributes the heat developed over the whole at the same time.
The porosity of the carbon allows the copper solution of the electrolysis to
penetrate it and reduces the resistance of the carbon mass.
The sub-division of the microphone into a certain number of similar and dis-
tinctive parts, has for purpose to reduce the intensity of the sparkings by excess
of voltage, without necessitating the use of compressed granulate which would
greatly reduce the sensitiveness of the contact, known as telephonic contact.
The microphone is mounted or set up in such a manner as not to necessitate
regulation on the part of the constructor, by which I mean to no greater an extent
than agents charged with this after-maintenance.

page_text: The resistance of the connections of the primary circuit and of all parts of the
microphone is considerably reduced and the hearing rendered more powerful or
ntense by the almost total suppression of the interior resistance of the secondary
lements, by the reduction to a third of the resistance of the primary circuit of
he induction coil, by the diminution of the length and the increase in section of
all the auxiliary wires, by the jointing to the metal of the lozenge, of the two
ntakes or receivers of the microphone's current.
The warming or heating of the granulate and of the lozenges of the microphone
increases the conductibility of the carbon and dries the surrounding air.
The dessicating effect of the tube full of magnesium chloride or of a similar product
and of absorbent cellulose powder, ensures a constant state of dryness to the
vibrating diaphragm or membrane, to the carbon and to the air surrounding the
granulate.
The induction coil introduces a very feeble resistance in the circuit.
The third circuit termed separator, closed on itself, favourably influences self-
induction and affords undulatory circuits of a quality superior to those of other
systems.
The primary circuit, and the secondary circuit induce or act by induction on
the third circuit which, in its turn, induces on them.
The generator has a very feeble interior resistance. It has displaceable energy
one hundred times greater than that of the primary batteries other than the block
battery.
The recharge practically effects itself.
The call generator and the call magnet are economically replaced by the second
battery.
The suppression of the source of the charge is made automatically, thanks to
the coincidence of the voltages. The call push or handle can be dispensed with,
as also the operation required therefor.
The inversion or change of the microphonic current which takes place auto-
matically has for advantages the preservation of the properties of the constituent
parts of the microphone, the diminishing of the harmful effect known as settling
or sinking of the granulate.
The receivers are very powerful whilst bearing in the circuit for each post or
station a resistance about eight times less than other systems.
If there be caused to intervene the difference of resistance of the secondary
circuit of the inducing coil, it will be found that the resistance of the apparatus
of the two posts or stations of any one circuit, not including the resistance from
self-induction is 10 times less in the Germain post or station than in other systems.
The combination of the second breaker or interrupter hook or claw-arm allows
the whole action of the current to be concentrated on the single unhooked
receiver.
The production of current in quantity on the secondary circuit where the
apparatus of the post have a very feeble resistance, is very suitable and convenient
for communication on badly insulated circuits, on cables with graduated shunts
and on all circuits of reduced resistance by graduated shunts.
The relay allows of other sections being added to the limit sections on which
correspondence takes place with ordinary apparatus. It allows important under-
ground sections to be added to the longest overhead lines along which communica-
tion now takes place, and even communication along lengthy underground or
submarine circuits.
The use of relays at each end of the circuit joining the central offices or
exchanges would allow all conversations to be improved or intensified on all
systems independently of the value of the different systems of subscribers.
Finally the use of currents for quantity, having a feeble voltage on long circuits
affected by simultaneous telegraphy and telephony, as well as the sectioning of
these circuits and the use of intermediary relays, improves the hearing and tele-
graphic transmissions.

page_text: The different parts of my telephonic post or station being thus described and
their working being set forth, I wish to state that I may alter the arrangement
and construction of the parts without departing from the principle of my
invention.
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:-
10. A microphone formed essentially of two lozenges made of carbon baked
at a very high temperature in an electrical furnace, arranged parallel, and between
which are formed divisions of equal surface for enclosing the granulated carbon;
these divisions thus forming calibrated capacities thereby dispensing with all
adjustment, the said microphone possessing the advantage of being able to work
at high voltages from 1 to 20 volts. for example, as above described and set forth.
20. In a microphone, lozenges of porous carbon metallized by electrolysis,
on the one hand in the mass, on the other hand on the inactive surfaces, the in-
takes and receivers of current being able to be directly connected to the metal
deposited on the inactive surface, as above described and set forth.
30. In a microphone, lozenges such as claimed in Claims 1 and 2 having
their active surface furnished with asperities, as above described and set forth.
4°. The combination with a microphone furnished with powder or granulate,
and more particularly with that claimed in Claims 1, 2, and 3, of a tube or recep-
tacle filled with substances for absorbing moisture from the air, such as magnesium
chloride, the said arrangement being preferably placed in a closed case or holder,
of which the vibrating membrane or diaphragm of the microphone forms one
wall, as above described and set forth.
5°. In combination with a telephonic post, an induction coil, of which the
primary circuit and the secondary circuit are composed of multiple wires connected
together for quantity, thus allowing the resistance to be reduced without dimin-
ishing the number of turns, as above described and set forth.
Go. In combination with a telephonic post a combination or assembling of
similar and distinct induction coils, allowing several arrangement combinations
of primary and secondary circuits to be effected, the said arrangements or group-
ings being performed either by the help of multiple commutators (such as the com-
mutator V, Figures 9, 10, 11, 13, 14) or in a permanent manner as above described
and set forth, an assemblage of four mounted coils with a multiple commutator
being above described.
70. In combination with a telephonic post the use of a third circuit, termed
"separator" which is closed on itself and inserted between the primary and the
secondary circuit, for the purpose of producing favourable effects due to the
reciprocal induction of the three circuits between them, as above described and
set forth.
8°. As a source of electrical energy applicable to a telephonic post, a secondary
generator self-charging for quantity by means of a battery in tension by the inter-
mediary of a multiple commutator actuated automatically by the action or play
of the commutator hook at each unhooking and hooking of the receiver, this com-
mutator effecting also the inversion alternatively of the current at the time of
successive couplings up in tension, the said secondary generator being as near as
possible to the post so that the primary battery can be distant therefrom, as above
described and set forth.
90. In combination with the whole of a primary generator and of a secondary
battery, as claimed in Claim 8, the use of a rheostat interposed in the charge
circuit, allowing a resistance to be established with relation to the maximum
output of current which takes place in each telephonic post, with a view to
reducing to a minimum the output or charge current when this is effected as above
described and set forth.

page_text: 10°. As an element of a secondary battery employed as a source of electricity
for a telephonic post, an element composed of a gauge of glass or other suitable
substance, of two small plates arranged parallel in a rubber plug or ring closing
the receiver, as above described and set forth.
11°. A telephonic receiver with elongated coils, very much brought together
from the centre of the armature, the circuits of the coils being arranged for
quantity, and the box being enveloped with soft rubber, as above described and
set forth.
12°. In a telephonic post furnished with two receivers, the arrangement of a
hook commutator, putting out of circuit the second receiver when only one is
being used, as above described and set forth.
13. In combination with a telephonic post, a lightning arrester composed of
several filaments of carbon arranged for quantity in a closed vacuum-bearing
case or chamber, the said filaments having a very feeble solution of continuity
and the said apparatus being able to be easily carried out by means of several
incandescence lamps of low voltage burned by an intense current and arranged for
quantity, as above described and set forth.
14°. A telephonic relay formed essentially of a magnet permanently furnished
at its poles with iron cores surrounded by an insulating circuit, the pole of the
iron core being covered with a thin layer or lozenge of carbon coated with copper
on its face in contact with the iron, a second layer or lozenge of carbon being
maintained at a certain distance from the said lozenge and the space between these
two lozenges being filled with granulated carbon, as above described and set
forth.
15°. The method of regulating a telephonic relay such as is claimed in
Claim 14, consisting of more or less compressing the granulated carbon by the
displacement of the lozenge closing the recess where this granulate is, the dis-
placement being attained by a suitable arrangement, as above described and set
forth.
16°. The method of regulating a telephonic relay such as that claimed in 14,
consisting of mounting the apparatus on an axis, preferably by its centre of
gravity, so as to be able to give different inclinations to the mass of granulated
carbon with a view to effecting the regulation by pressure and the distribution
of the granulate according to gravity, as above described and set forth.
17°. A special kind of granulate more particularly applicable to a telephonic
relay such as that claimed in 14, each fragment of the said granulate being
formed of a magnetic core, usually of iron surrounded by carbon, as above
described and set forth.
18°. The installation arrangement of a telephonic relay characterised by the
use of two similar relays, preferably arranged on the same socket, the secondary
circuits of the two induction bobbins being in tension, on the line circuit, as above
described and set forth.
19°. The arrangement of the whole of a complete telephonic post, comprising
the different parts claimed in the foregoing, constructed, combined and arranged,
substantially as and for the purposes described.
3 Dated this Ninth day of December 1898