A New or Improved Mode of Long Distance Telephoning, and in Apparatus therefor.
Year: 1897

page_text: Date of Application, 23rd Apr., 1897
Complete Specification Left, 20th Jan., 1898-Accepted, 26th Feb.,
1898
PROVISIONAL SPECIFICATION.
A New or Improved Mode of Long Distance Telephoning, and in
Apparatus therefor.
I, IGNAZIO GIULIANI, of Via Cairoli 2, Milan, in the Kingdom of Italy, do hereby
declare the nature of this invention to be as follows:
-
This apparatus differs from telephonic apparatus now in use because the micro-
phone does not constitute with the induction-coil and the battery a local circuit,
but on the contrary excluding the induction coil it receives the derived current
which passes to the wire of the line; thus by this peculiar disposition speaking at
great distances only subordinately to the intensity of the current of the battery is
possible.
With the hitherto used apparatus the telephonic correspondence must be limited
to certain distances, as the very weak induced currents do not succeed in overcoming
the resistance of a long line; in the present case this resistance, on the contrary,
can be overcome by augmenting the electric energy with regard to the resistances
comprised in the exterior circuit.
The invention is performed by simplifying the apparatus now in use, the micro-
phone being without induction coil, and the telephonic circuit is very simple. The
two extremities of the microphone pass directly to the battery from which pass also
the wires of which one ends at the receiving telephone and the other passes to earth.
The microphone operating in this manner upon a very short circuit conserves all
its energy, and the variations of resistance in the microphone itself produced by the
vibrations of the voice alter consequently the intensity of the current circulating in
the wire of the line.
Any variation of this current makes the telephone operate and the words are
reproduced even at a distance of hundreds of miles.
Besides the microphone the apparatus comprises a bell which receives the current
of the line with a hook on which the telephone receiver is suspended; a commutator
with three contacts of which the one establishes communication with the bell, and
the two others when placed in contact but excluding the bell serve eventually to
bring the microphone and the line battery into circuit.
There is a button in order to operate the bell of the correspondent, and an earth
plate inserted in the wire of the line.
HERBERT HADDAN & Co.,
Agents to the Applicant.
A New or Improved Mode of Long Distance Telephoning, and
Apparatus therefor.
I, IGNAZIO GIULIANI, of Via Cairoli 2, Milan, in the Kingdom of Italy, do hereby
declare the nature of this invention and in what manner the same is to be per
Price 8d1

page_text: formed to be particularly described and ascertained in and by the following
statement:
-
This apparatus differs from telephonic apparatus now in use, because the micro-
phone does not constitute a local circuit with the induction coil and the battery,
but on the contrary the induction coil is excluded and the microphone receives the
derived current which passes to the wire of the line by this method speaking at
great distances-limited-only-according to the intensity of the current from the
battery is possible.
With the hitherto used apparatus telephonic correspondence must be limited
to certain distances, as the very weak induced currents do not succeed in over-
coming the resistance of a long line; in the present case this resistance can be
overcome by augmenting the electric energy with regard to the resistance com-
prised in the exterior circuit.
In the annexed drawing:-Figs. 1 and 2 illustrate method of connection and
the apparatus used.
Fig. shows a simplified form of the apparatus now in use, a microphone only
being used without an induction coil, the telephonic circuit being very simple.
The two extremities ab of the microphone M are directly connected to the battery P
to which are also connected the wires cd of which one passes to the receiving
telephone and the other to earth.
The microphone operating in this manner upon a very short circuit preserves
all its energy, and the variations of resistance in the microphone itself produced
by the vibrations of the voice, alter consequently the intensity of the current circu-
lating in the line wire.
Any variation of this current makes the telephone operate and the words are
reproduced even at a distance of hundreds of miles.
In Fig. 2 besides the microphone M the apparatus comprises a bell S which
receives the current of the, line a hook L on which the telephone receiver is sus-
pended; a commutator C with three contacts of which one establishes communica-
tion with the bell, and the two others when placed in contact but excluding the bell,
bring the microphone and the line battery into circuit.
There is also a button B operating the bell of the correspondent, and an earth
plate T connected with the line wire.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. A telephonic apparatus in which the microphone or transmitter is connected
in derivation with the battery of the line wire circuit substantially as set forth.
2. The improvements in telephonic apparatus for long distance telephoning
substantially as set forth.
Dated this 20th day of January 1898.
HERBERT HADDAN & Co.,
Agents to Applicant, 18, Buckingham Street, Strand, London.