IMPROVEMENTS IN TELEPHONES AND TELEPHONIC SYSTEMS
Year: 1885

page_text: I, PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex, Fellow of the Institute of Patent Agents, do hereby declare the nature
of said invention for "IMPROVEMENTS IN TELEPHONES AND TELEPHONIC SYSTEMS"
a communication to me from abroad by Thomas Wallace of Exchange Place in the
City, County and State of New York United States of America Electrician to be
as follows:
The telephones heretofore constructed may be classified under the general heads
of magnetic, and electric or battery telephones.
The former or magnetic class have been generally used as receivers to translate
the electrical variations passing over the line into air or sound vibrations such as
are caused by the utterance of speech. In some instances their use as transmitters,
to translate the air or sound vibrations into electrical variations, has been suggested
but they have been found to produce but feeble results and their use as both
transmitters and receivers has been abandoned.
The electric or battery telephone has been almost universally used as a trans-
mitter and whenever it becomes necessary to send messages any considerable
distance, the transmitter instrument is included in the primary of an inductorium,
the secondary of which is included in the line circuit.
In this way the variations in the comparatively weak galvanic current have
been transformed by the use of the inductorium into comparatively strong. or
intense secondary currents which have been received and translated into speech by
a magneto receiver.
This necessitates not only the use at each station of two separate telephonic
instruments of different classes, each of which is more or less complicated and
expensive, but also a local battery and an inductorium which also add greatly to
and are extremely liable to derangement and destruction.
the expense
There are, thus, to be found in the ordinary telephonic line or system, as for the
connection of two stations for instance, two local batteries, two battery transmitting
instruments of greater or less complexity of construction two magneto receiving:

page_text: instruments, each consisting of a magnet core, helix and diaphragm; two expensive
induction coils including the two primary and the line circuits and the necessary
signalling instruments, if used.
The object of my invention is to produce an electric telephonic system, embracing
neither magnet cores or helices, local circuits, or induction coils, and to use the
same form of battery telephone both as a transmitter and a receiver.
My invention is based substantially upon the discovery or invention of a battery
telephone, that may be practically used without change of construction or adjust-
ment either as a transmitting or a receiving telephone.
One of the earliest forms of speaking telephones consisted of a standard having
two projecting lugs of carbon with a block or pencil of carbon having pointed ends
fitting into recesses in the carbon lugs on the standard.
This instrument, with various modifications and multiplications has been used
successfully as a transmitting instrument and I have found that by changing the
construction of such instrument in a manner substantially as pointed out hereafter
and connecting it up in line as hereafter indicated it may not only be used as a
transmitter but as a successful receiver, and this without any of the usual adjuncts
of a system as heretofore pointed out except a charged line, and I have further
found that such an instrument requires no fine adjustment and regulation, but
once constructed and set up is practically self-regulating and adjusting, and equally
adapted to operate both as a transmitter and receiver instrument.
The arrangement and combination of parts may be described as follows.
To a resonant body are connected or attached two studs, projections or bearing
pieces of carbon or similar substance having sockets or bearings formed therein.
Fitting into these sockets or bearings preferably somewhat loosely, is a bar, rod or
pencil of carbon or its equivalent. Upon this bar of carbon is placed or fitted a
weighted covering or casing of some substance preferably metallic such as lead,
platinum, or aluminium in the form of foil or laminae, or otherwise. I found by
experiment that the substance known as tea-lead-foil is cheap, effective, and easily
and readily applied, and I preferably use it, though of course other substances may
be used that produce the same or similar results.
Such are the essential features of my instrument and the details may be varied
in many ways without departing from my invention. The studs or projections
may be mounted upon a disc shaped sounding board or resonator which may be of
any material preferred and this may be used in any suitable or conveniently shaped
case or the bearings may be mounted upon studs or standards fixed to the sides of
a cup shaped resonating case having the usual mouth or ear piece and having an
opening to which a tube may be applied so that the same instrument may be used
as a receiver and transmitter without change of position. The contact pieces may
be conveniently supported upon a rectangular plate of wood or similar material
carried in a suitable frame, having convenient binding posts.
From this it will be readily understood that it is immaterial to the essence of
this part of my invention in what form or construction of case the contact pieces
may be carried, it only being necessary that some part thereof be of resonant
material.
An instrument as thus constructed has by experiment been found to work
practically as both a transmitter and receiver and such instruments may be
connected up in a system or line in a manner which will be readily understood
by electricians.
It will be understood that the galvanic circuit passes from one pole of the
battery through the studs and carbon rod directly to line, the instrument intended
to be used as a receiver being in a short or branch circuit around the transmitter
and battery. Such an arrangement necessitates the use of a battery at each end of
the line, but the receiving instrument may be placed directly in the main circuit
as in the case where a single instrument is used both as a transmitter and a
receiver.

page_text: It will thus be seen that I produce a complete telephonic line or system
without the use of any magnet or coils, local battery circuits or inductoriums, and
that owing to the simple construction of instruments no fine adjustments are
required.
I have found that I can use a relatively strong battery current and am thereby
enabled to transmit speech over long distances, and this without the usual rattling
often found in transmitters of this character; and that the disturbances attributed
to induction &c are practically nullified.
I have also found that the instrument is very effective as a receiver when the
bar or studs or both are composed of comparatively soft and porous carbon in
contradistinction to hard compact carbon.

page_text: COMPLETE
DI BUITICALIA,
I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex, Fellow of the Institute of Patent Agents do hereby declare the nature
of my said invention for IMPROVEMENTS IN TELEPHONES AND TELEPHONIC SYSTEMS
a communication to me from abroad by Thomas Wallace of Exchange Place in the
City, County and State of New York United States of America Electrician and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :—
The telophones heretofore constructed may be classified under the general heads
of magnetic, and electric or battery telephones.
The former or magnetic class have been generally used as receivers to translate
the electrical variations passing over the line into air or sound vibrations such as
are caused by the utterance of speech. In some instances their use as transmitters,
to translate the air or sound vibrations into electrical variations, has been suggested,
but they have been found to produce but feeble results and their use as both
transmitters and receivers has been abandoned.
The electric or battery telephone has been almost universally used as a trans-
mitter and whenever it becomes necessary to send messages any considerable
distance, the transmitter instrument is included in the primary of an inductorium,
the secondary of which is included in the line circuit. In this way the variations
in the comparatively weak galvanic current have been transformed by the use of
the inductorium into comparatively strong or intense secondary currents which
have been received and translated into speech by a magneto receiver.
This necessitates not only the use at each station of two separate telephonic
instruments of different classes, each of which is more or less complicated and
expensive, but also a local battery and an inductorium which also add greatly to
the expense and are extremely liable to derangement and destruction.
There are, thus, to be found in the ordinary telephonic line or system, as for the
connection of two stations for instance, two local batteries, two battery transmitting
instruments of greater or less complexity of construction; two magneto receiving
instruments, each consisting of a magnet core, helix and diaphragm; two expensive
induction coils including the two primary and the line circuits and the necessary
signalling instruments, if used.
The object of my invention is to produce an electric telephonic system, embracing
neither magnet, cores or helices, local circuits, or induction coils, and to use the same
form of battery telephone both as a transmitter and a receiver.
My invention is based substantially upon the discovery or invention of a battery
telephone, that may be practically used without change of construction or adjust-
ment either as a transmitting or a receiving telephone.
One of the earliest forms of speaking telephones consisted of a standard having
two projecting lugs of carbon with a block or pencil of carbon having pointed ends
fitting into recesses in the carbon lugs on the standard.
This instrument, with various modifications and multiplications, has been used
successfully as a transmitting instrument, and I have found that by changing the

page_text: construction of such instrument in a manner substantially as pointed out hereafter
and connecting it up in line as hereafter indicated, it may not only be used as a
transmitter but as a successful receiver, and this without any of the usual adjuncts
of a system as heretofore pointed out except a charged line, and I have further
found that such an instrument requires no fine adjustment and regulation, but once
constructed and set up is practically self regulating and adjusting, and equally
adapted to operate both as a transmitter and receiver instrument.
I will now proceed to describe my invention with reference to the accompanying
drawings, which form part of this specification, in which―
Figure, 1. is a plan view of the principal parts of a telephone embodying my
invention.
Figure, 2. is a section of another form of instrument.
Figure. 3, is a diagram of a line or system for two stations, showing my inven-
tion and disclosing still other, forms of telephonic instruments embodying the same,
and
.Figure. 4, is a diagram showing the use of one telephone as both the transmitting
and receiving instrument at each station.
Similar letters of reference refer to like parts in all the figures.
The arrangement and combination of parts may be described as follows:-
To a resonant body A, are connected or attached two studs, projection or bearing
pieces B, B1, of carbon or similar substance, having sockets or bearings C. C¹, formed
therein. Fitting into these sockets or bearings, preferably somewhat loosely, is a
bar, rod or pencil D, of carbon or its equivalent. Upon this bar of carbon is placed
or fitted a weighted covering or casing E, of some substance, preferably metallic,
such as lead, platinum, or aluminium, in the form of foil or laminae, or otherwise.
I have found by experiment that the substance known as tea-lead-foil is cheap,
effective and easily and readily applied, and I preferably use it, though of course
other substances may be used that produce the same or similar results.
Such are the essential features of my instrument and the details may be varied
in many ways without departing from my invention. In figure 1 the studs or
projections B, B1. are represented as being mounted upon a disc shaped sounding
board or resonator which may be of any material preferred, and this may be used
in any suitable or conveniently shaped case as shown in the receiver R, in Figure 3.
In Figure 2 the bearings B, B¹, are shown as mounted upon studs or standards G, G¹,
fixed to the sides of a cup shaped resonating case A, having the usual mouth or ear
piece I, and having an opening J to which a tube T may be applied so that the
same instrument may be used as a receiver and transmitter without change of
position. In Figure 3 the contact pieces are shewn as-supported upon a rectangular
plate K of wood or similar material carried in a suitable frame, having convenient
binding posts.
From this it will be readily understood that it is immaterial to the essence of
this part of my invention in what form or construction of case the contact pieces
may be carried, it only being necessary that some part thereof be of resonant
material.
An instrument as thus constructed has by experiment been found to work
practically as both a transmitter and receiver and in Figure 3 I have illustrated
one manner of connecting such instruments up in a system or line, which will be
readily understood by electricians It will be seen that the galvanic circuit passes
from one pole of the battery through the studs B, B', and carbon rod D directly to
line, the instrument intended to be used as a receiver being in a short or branch
circuit around the transmitter and battery. Such an arrangement necessitates the
use of a battery at each end of the line, but the receiving instrument may be
placed directly in the main circuit as in the case where a single instrument is used
both as a transmitter and a receiver.
It will thus be seen that I produce a complete telephonic line or system without
the use of any magnet or coils, local battery circuits or inductoriums, and that
owing to the simple construction of instruments no fine adjustments are required.

page_text: r
I have found that I can use à relatively strong battery current and am thereby
enabled to transmit speech over, long distances, and this without the usual rattling
often found in transmitters of this character, and that the disturbances attributed
to induction, &c, are practically nullified.
I have also found that the instrument is very effective as a receiver when the
bar or studs or both are composed of comparatively soft and porous carbon in
contradistinction to bard compact carbon. It will be understood that I do not
confine myself to the exact form of instrument or apparatus shown and described
but-
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, as communicated to
me from abroad by my foreign correspondent. I declare that what I claim is
1. A telephone instrument consisting of a resonant body, a bar of carbon sup-
ported in carbon bearings, and a weighted covering or casing for said bar,
substantially as described.
2. A telephonic receiver consisting of a weighted bar of carbon supported in
carbon bearings, in connection with a resonating body substantially as described.
3. A combined transmitting and receiving telephone instrument consisting of a
rod of carbon supported in carbon bearings, in connection with a resonating body,
and suitable mouth and ear connections, substantially as described.
4. A contact piece for telephones consisting of a bar or rod of carbon, or similar
low conducting material, having a covering or casing of metallic foil, substantially
as described.
5. A contact piece for telephones, consisting of a bar of carbon having a covering
of tea-lead-foil, substantially as described.
6. A telephonic system or line embracing a galvanic circuit including two or
more instruments, each consisting of a carbon bar supported in bearings, in con-
nection with a resonant body, and adapted to act both as a transmitter and
receiver, whereby speech may be transmitted and received without the use of
magnets, coils, inductoriums, or diaphragms, substantially as set forth.
7. The combination with a charged line circuit, of a transmitter consisting
essentially of a carbon rod supported in carbon bearings upon a resonant body
arranged in the main galvanic current, and a receiver consisting of a similar carbon
rod supported in carbon bearings and connected to a resonant body, in a branch
circuit around the transmitter, substantially as described.
Deted this thirteenth day of March 1885