IMPROVED SYSTEM OF TELEPHONES
Year: 1885

page_text: I ABNER MULHOLLAND ROSEBRUGH of 121 Church Street in the City of Toronto
in the Province of Ontario Canada but at present at 16 Norfolk Street Strand in
the County of Middlesex Surgeon do hereby declare the nature of my Invention
for "IMPROVED SYSTEM OF TELEPHONES" to be as follows:-
My Improvements relate to a system of Mechanical Telephones or as I prefer to
term them "Speaking Tube Telephones" and to arrangements whereby the said
systems are rendered available for exchange purposes.
One part of my improved system relates to the construction of the line the
object being to diminish or eliminate the harsh metallic vibrations incident to such
telephones as now used. The improvement consists in using cord for the whole or
part of the line and preferably using cord that has been saturated in oil to make it
more durable.
In cases where wire is used the connection with the telephones are made with
cord and cord is also used in parts of the line where said line is made to deviate
from a straight line. The cord is preferably accompanied by a fine wire to be used
for electrical signalling and said fine wire may be wound around or form part of
said cord and in cases where the line is divided into sections as herein described;
the fine wire accompanying said cord is made to make metallic connection with
the all wire section so as to establish metallic connection between the two
telephones.
Another point in my system is the mounting of the diaphragm. This may be
either of stiff material such as ebonite, sheet metal, mica, slate or wood, or of some
flexible material such as silk, felt, parchment, straw &c. strained or affixed over or
upon or within a ring casing or other rigid frame, but in either case I mount it by.
an elastic or yielding cushion, such as a ring of india rubber interposed between
the said diaphragm or frame thereof and the box board casing or mouthpiece in
which it is mounted. I find that the said cushion contributes to the good a oustic
qualities of the instrument and eliminates lateral vibrations.
The instruments may be placed against the wall or other support in the room of
the house or office of the person who wishes to use it, the line being brought
through a suitable aperture in the wall. Or where more convenient I place the
instrument itself outside the house affixing it to the roof or wall where the line can
170

page_text: be brought straight to the diaphragm and on one or both sides of the diaphragm
I connect by suitable sockets or cavities or supports a speaking tube or tubes which
pass through the wall of the house into the room or office. By this latter arrange-
ment I am enabled to do away with many of the difficulties attendant on bringing
the line wire round corners into the desired point in the interior of the house.
In order to facilitate the turning of angles when the line deviates from a straight
course I employ the following device namely a short tube bent at the desired angle
is provided with a suitable diaphragm of ebonite wood silk, felt, leather, mica,
metal or other material, at one or both of its ends so that the air in the tube
conveys the sounds from one diaphragm round the bend to the other diaphragm.
And in case the line is also used as an electric conductor to convey electric bell
signals I then carry a light metal wire from the line on one side of the tube to the
line on the other so as to maintain electric continuity.
When my system of speaking tube Telephones is used for working an exchange
system, I use preferably flexible tubes for connecting the mouth piece of one
telephone with the mouth piece of any other telephone in said exchange. The
lines from the subscribers may in this case be used for working the annunciators
or call bells electrically. The telephones at the central office may be either within
the building the lines coming in through suitable apertures or they may be outside
the building as described above, having tubes to bring the sounds to and from the
diaphragms to within the office. In this case any two subscribers may be con-
nected by placing the ends of a curved or flexible or other tube over or into or
against the ends of the tubes of the two subscribers who desire to be put into
communication. The connecting tube inay itself be of metallic materials, capable
of conducting electricity, or having wound, inserted or woven into or upon it a
suitable wire or strip of metal to conduct electricity for the purpose of establishing
electric continuity between the telephones of two subscribers the mouthpieces of
their telephones or of the tubes communicating with them being furnished also
with corresponding electrical connexions or switches. This arrangement of the
system will therefore automatically put the call bell apparatus of any two sub-
scribers into communication at the same inoment that they are placed in acoustic
communication with one another through the connecting tube with which their
telephones are joined.
When several of these pliable connecting tubes are used they may be designated
by colours letters or numbers so as to facilitate the making of the proper
connections.

page_text: improved рубеш от догорнодо
I ABNER MULHOLLAND ROSEBRUGH of 121 Church Street in the City of Toronto
in the Province of Ontario, Canada, Surgeon 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:-
My Invention relates to systems of mechanical telephones or as I prefer to term
them "Speaking Tube Telephones" and to arrangements whereby the said systems
are rendered available for exchange purposes. One part of my improved system
relates to the construction of the line, the object being to diminish or eliminate the
harsh metallic vibrations incident to such telephones as now used. In carrying
out my Invention I may use cord for the whole or for part of the line, preferably
cord, that has been saturated in oil to make it more durable.
In cases where wire is used for the line, the connections with the telephones are
male with cord, and cord is also used in parts of the line where said line is made
to deviate from a straight course. The cord is preferably accompanied by a fine
wire to be used for electrical signalling, the said wire being wound around the cord
or forming part thereof, and in cases where the line is divided into sections as
hereinafter described the fine wire accompanying the cord is arranged to make
metallic connections with the all wire section so as to establish metallic connection
between the two telephones.
Another feature in my system relates to the mounting of the diaphragms used
to receive the air waves.-These diaphragms may be made either of stiff material,
such as ebonite sheet metal mica slate or wood or of any flexible material such as
silk felt parchment straw or the like strained or affixed upon or within a ring
casing or other rigid frame but in either case I mount the diaphragm with an
insulating elastic or yielding cushion or packing such as a ring of india-rubber
interposed between it and the box-board casing or mouthpiece in or on which it is
mounted or by which it is .carried and I find that the said cushion contributes to
the good acoustic qualities of the instrument and eliminates lateral vibrations.
The instrument may be placed against the wall or other support in the room of
the house or office of the person who wishes to use it, the line being brought
through a suitable aperture in the wall or the like. Or, where more convenient,
I place the instrument itself outside the house affixing it to the roof or wall where
the line can be brought straight to the diaphragm and on one or both sides of the
diaphragm I connect by suitable sockets or cavities or supports a speaking tube or
tubes which pass through the walls of the house into the room or office. By this
latter arrangement I am enabled to dispense with many of the difficulties attendant
on bringing the line wire round corners into the desired point in the interior of
the house.
In order to facilitate the turning of angles when the line deviates from a straight
course, I employ the following device, namely, a short tube bent at the desired

page_text: angle, is provided with a suitable diaphragm of ebonite wood felt silk leather mica
metal or other material at one or both of its ends so that the air in the tube
conveys the sounds from one diaphragm round the bend in the tube to the other
diaphragm, and in case the line is also used as an electric conductor to convey
electric bell signals, I then carry a light metal wire from the line on one side of
the tube to the line on the other side thereof so as to maintain electric continuity.
When my improved system of speaking tube telephones is used for working an
exchange system, I use preferably flexible tubes for connecting the mouth-piece of
one Telephone with the mouthpiece of another telephone in said exchange. The
lines from the subscribers may in this case also be used for working the annunciators
or call bells electrically.
The telephones at the central office may be either within the building, the lines
coming in through suitable apertures, or they may be outside the building as
herein before described, having tubes to conduct the sound vibrations of the
diaphragms to and from the interior of the building. In this case, any two sub-
scribers may be connected by placing the ends of a curved or flexible or other tube
over or into or against the ends of the tubes of the two subscribers who desire
to be put into communication. The connecting tube may itself be of metallic
Inaterials, capable of conducting electricity or having wound, inserted or woven
into or upon it, a suitable wire or strip of metal to conduct electricity for the
purpose of establishing electric continuity between the telephones of two sub-
scribers, the mouthpieces of their telephones or of the tubes communicating with
them being furnished also with corresponding electrical connections or switches or
the metallic continuity may be made by wires or the like extending across from
one part of the line to another to bridge across any place where metallic continuity
would otherwise cease. By these arrangements, for providing metallic continuity
between the instruments, the call bell apparatus of any two subscribers may be
automatically placed in communication at the same moment that they are placed
in acoustic communication with one another, through the connecting tube with
which their telephones are joined.
When several of these pliable connecting tubes are used, they may be designated
by colors, letters or numbers, so as to facilitate the making of the proper
connections.
And in order that my said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying drawings is a diagram illustrating the arrange-
ment of a telephonic system according to my Invention. A B represents two
subscribers lines terminating in an exchange office the switch board of which office
is represented at C. D¹ D' are the subscribers telephones from the exchange and
in connection with the lines A and B respectively. Where it is desirable or
necessary to conduct the line round corners or to cause it to deviate from a straight
course it is connected to or passed through a tube bent to the desired angle or line
of divergence as shewn at E1 E2-These tubes are each provided at each end with
a diaphragm e to which the line is attached the line when severed being made
metallically continuous by the thin wire b. The said tubes where they are at the
end of the line will have but one diaphragm which is connected to the line.
The sound in this case is transmitted to and received from the line by means of
the said tubes. But where the said tubes are not so situated there is a diaphragm
at each end of the said tubes and the line is attached to both diaphragms so that a
continuation of the line is thereby formed.
The diaphragms e may be of greater diameter than the tube E as shewn in this
figure or they may. be of less diameter and be fitted to the interior thereof as
shewn at E Figure 2, which figure represents several forms of conducting tubes
according to my invention. Instead of severing the line for turning corners it

page_text: may be continued through the tubes as shewn at E Figure 2 in which case it is
preferable and sometimes necessary to support the line inside the tube by one or
more intermediate diaphragms as at e to keep it out of contact with the tube
the said intermediate diaphragms being perforated for the passage of the line.
The mouthpiece F of a subscribers telephone may be connected directly to the
case D containing the diaphragms as shewn applied to the line A Figure 1 or it
may be connected to a speaking tube G arranged between the mouthpiece F and
the case D of the diaphragm as shewn in connection with the line B Figure 1.
Or the mouth piece F and the case D to which the diaphragm is fitted may be
separated by a length of flexible tubing H as shewn in figure 3 to admit of both
the mouthpiece F and the telephone receiving and transmitting instrument being
arranged in any convenient position. The flexible tube H may be made entirely
of metal or it may be made of non-metallic material and have a metallic wire or
strip twisted therewith or wound thereon or attached thereto in any convenient
way for the purpose of making a metallic connection between the line and the
electric signalling apparatus I as shewn, which apparatus is connected to the earth
by the wire K, it being of course arranged at the other end to give the requisite
circuit.
The lines of the several subscribers may be conducted to the central exchange
office through tubes L fitted in a cupola on the roof of the building in which the
exchange office is situated or in other convenient position. Figure 4 shews an
arrangement on this plan in which A B A¹ B¹ A B² A³ B³ represent telephone lines
leading from subscribers telephones and connected to diaphragms in the telephone
cases D fitted on the upper ends of the tubes L which tubes are attached at their
lower ends to the switch boards in the exchange office below, but of course, lines
passing through the ground can be similarly led upwards.
Figure 5 represents a modification of the foregoing, in which the subscribers
lines A A B and so on, proceed direct from the switch-board C without the inter-
vention of the speaking tubes shewn in figure 4. In the arrangement illustrated
by figure 4 the switch board C is secured preferably in an upright position and
is perforated for the passage of the speaking tubes leading to the lines the telephone
or diaphragm cases being placed behind the speaking tubes the lower ends of which
project from the front side of the switch board and they are each provided with a
short tube so that connection may be made between two telephones, by means of
the flexible coupling tube N, Figures 4 and 5.
These projecting tubes are preferably arranged so that acoustic connection may
be made between any two subscribers lines at pleasure by simply sliding the two
ends of the tube N. over projecting ends of the tubes appertaining to the lines of
the subscribers to be put in communication.
Figure 6 is a front elevation, partly in perspective, of a combination of three-
switch boards in an exchange office. 1, are the ends of the speaking tubes pro-
jecting in front of the switch-boards C. L represent the speaking tubes extending
from the switch-board to the telephone lines and N are the flexible coupling tubes,
the central portion of each of which is preferably rigid and the ends thereof
metallic and curved as shown. P. Q. are tubes for coupling the telephones of one
switch board with those of another switch board.
Figure 7 is a detached view of the operators mouthpiece F1 and connecting
tube N¹ for use at the central station and figure 8 is a vertical section of part of a
switch board with the mouthpiece and speaking tube in position for speaking.
The mouthpiece is preferably of large size and is provided with a tube S for
conveying acoustic vibrations to the ear of the operator while the mouth is at the
mouthpiece as shewn in figure 7.
This mouthpiece is preferably permanently attached to the switch board C for
example by a bracket as at x The free end of the tube N¹ is metallic or lined with
metal foil for the purpose of making metallic connection between the mouth piece
and the electric generator T of the signalling apparatus the metallic continuity

page_text: along or past the tube if necessary being provided for as herein before explained. A
portion of the free end of the flexible speaking tube N¹ is covered with a noncon-
ducting material shewn at P so that when the said tube is slidden upon one of the
line tubes L metallic connection is made between the operators' speaking tube N¹
and the line and at the same time the receiving annunciator U in connection there-
with is shunted from the circuit by the interposition of the nonconducting material,
attached to the end of the tube forcing the spring contact maker V out of contact
with the ends of the tube L the current to the communicator being thus shunted.
The communicator U is connected to earth by the wire K. The flexible coupling
tubes N are similarly provided with metallic tips at each end the tips being con-
nected by wire or its electrical equivalent so that when two lines are coupled by
means of one of the said tubes the said lines are electrically as well as acoustically.
connected.
A portion of the exterior surface of these metallic tips are covered with insulating
material as shewn at P Figure 1, 6 and 9 so that when two lines are connected by
the tube the spring contact makers Vin connection with the annunciators U are;
shunted out of circuit as hereinbefore described. It will be understood that by
this means the metallic circuit to the exchange will be complete to cause the annun->
ciator there to act and that when the attendant at the exchange has placed the
subscribes in communication the metallic circuit between the subscribers will be
complete whilst that which originally was complete to the annunciator at the
exchange will be broken it is to be understood however that I do not confine myself.
to any particular switching or shunting device so long as it is effected automatically
by the coupling tube or by the operators speaking tube.
X Figure 9 is a microphone communicating by a tube L on one side with the
switch board Cand on the other side with the mouthpiece Y of a magnetic telephone.
This telephone and the secondary coil of the microphone are connected with the
line on one side by the wire a and with the tube L spring V annunciator U and to
earth on the other side by the wire b. As a modification of this arrangement
the microphone and the electrical telephone may be combined so that one diaphragm
may serve for both.
The operation of my telephone system is as follows. Assuming for example that
subscriber belonging to line A figure 1 wishes to communicate with subscriber
belonging to line B he calls up the, exchange office by means of his electric
generator T the current therefrom passing to line through the fine wire c thence to
the annunciator through the tube L and spring V figure 8 and ground wire K at
the exchange office. The operator at the exchange office then places the speaking
tube N¹ in connection with the line A and answers the call. He then either
signals B or makes direct connection between A and B by one of the coupling
tubes N so as to allow A to call up and speak to B. In making connection
between A and B by means of tube N the subscribers A and B are placed
electrically and acoustically in communication with each other. When the sub-
scribers wishing to communicate are not connected with the same switchboard an
additional connecting tube P or Q. Figure 6 is used as hereinbefore explained and
when the two subscribers are not connected with the same exchange office they
may be placed in communication through the medium of an electrical telephone
trunk line as already described.
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
:
13
First In a mechanical telephone exchange system the use of a line or conveyor
of air waves composed throughout, the whole or part of its length of cord or
of tubes or, both with which is or are wound or combined thin wire or wires, or
the equivalent, thereof to make metallic continuity between the telephones sub-
stantially as and for the purpose hereinbefore described.

page_text: Second-In mechanical telephones the interposition of an elastic or yielding
cushion or packing between the diaphragm and the part in or on which it is
mounted or by which it is covered substantially as and for the purpose hereinbefore
described.
Third-In mechanical telephones a tube or elbow pipe provided with diaphragms
to which the line is attached so that the air in the tube acts as a conveyor of sound
from one portion to another of the line or system substantially as and for the purpose
hereinbefore described.
Fourth In mechanical telephones a tube or hollow conveyor attachable to the
mouthpieces or tubes leading from one subscribers line to another through the
exchange or the like substantially as herein before described and for the purpose of
conveying the air vibrations from any one line into the exchange and out therefrom
along any other line as required.
Fifth-The several arrangements or combinations of parts hereinbefore described
and illustrated in the several figures of the accompanying drawings.
J. HENRY JOHNSON,
Agent.