Improvements in Telephone System and Apparatus.
Year: 1899

page_text: Date of Application, 11th Dec., 1899-Accepted, 17th Mar., 1900
COMPLETE SPECIFICATION.
Improvements in Telephone System and Apparatus.
I, ELIAS ELKAN RIES, of 346, Broadway, in the City of New York, in the County
and State of New York, U.S.A., Electrical Engineer, do hereby declare the nature
of this invention and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement:-
My invention relates to certain improvements in the construction and application
of telephone receivers having a self-contained automatic switching device, by
means of which the circuit connections are automatically changed from the
signalling to the conversational condition by the natural operation of lifting the
receiver to the ear, and are restored to the signalling condition by permitting
the receiver to come to rest in its normal position.
"
The object of the present invention is, firstly, to insure greater certainty and
reliability in the operation of the circuit changing apparatus by providing for
a wider range of movement or permissible tilting of the receiver while the latter
is being used with the circuits in the conversational condition; secondly to adapt
the invention to telephone receivers of a more compact type, such for example
as the class known commonly heretofore as watch case receivers," in connection
with which my invention is designed to provide a convenient knob or holding
device by which such receivers may be more readily manipulated; thirdly to
permit a calling signal to be sent over the line by the person using the automatic
telephone, either preparatory to or during the process of using the instrument,
without recourse to and independently of the usual magneto calling apparatus,
thus greatly facilitating the process of telephonic communication and at the same
time simplifying the construction and reducing the cost of a subscriber's outfit.
A further object of the invention is to dispense with the stationary or fixed
gravity hook switches or supports heretofore employed, and to combine the various
instrumentalities for signalling, switching, and receiving in the form of a single
portable apparatus in a manner to cause these various operations to be rationally
and as it were automatically performed by the mere act of taking up and lifting
the apparatus to the ear. The apparatus is thus especially adapted to desk, office,
household, and other uses, both for interior and long distance circuits to which
uses existing types of telephonic apparatus are more or less inapplicable and objec-
tionable.
In carrying out the present invention the use of hook switches is dispensed
with and the receiver carries a gravity switch in which the circuit changing
medium consists preferably of a small quantity of miercury or other mobile con-
ductive medium contained within a suitably sealed chamber or receptacle, the
arrangement being such that the act of lifting the receiver to the ear will auto-
matically cause the said medium to shift its position from the space or portion of
the chamber where it is retained in position to complete the calling circuit to the
portion of the chamber or space where it is retained in a position to cut in the
receiver coil and the transmitter with its battery, while the dropping of the receiver
or the act of replacing or suspending it in its normal or vertical position while
the apparatus is out of use, will instantly restore the connection for calling or

page_text: receiving a calling signal by causing the mercury or other medium to flow by
gravity from the chamber where it is retained when the instrument is in position
for conversation through a suitable path or passage to the chamber where it is
retained in position to cut out the transmitter and cut in the calling circuit or
ringing off circuit.
In the drawings Fig. 1 is a sectional elevation of one form of my improved
automatic telephone receiver on the line b, b, Fig. 2, in its normal position showing
the form and arrangement of the conical mercury or switch chamber and the
calling apparatus.
Fig. 2, is a plan view of the same with the upper cap-piece and the calling
apparatus and its connections removed.
Fig. 3, is a detailed plan view of the main switch-contact cup containing the
auxiliary calling apparatus and showing the circuit connections.
Fig. 4, is an enlarged detail sectional view, in part of the knob containing the
calling apparatus, mercury chamber and the switch contacts, showing a slightly
modified construction.
Fig. 5, is a diagram showing the arrangement of the circuits and their connection
with the respective binding posts of the instrument, the auxiliary calling circuit
being shown in the dotted lines.
Fig. 6, is a detailed plan view of the upper switch contact ring shown in Fig's. 1
and 2.
Fig. 7, is a sectional elevation in the line d, d, Fig. 8; Fig. 8, a plan with
cap removed, of a modified form in which the circuit connections are brought out
at the top instead of at the side of the instrument, and showing the mercury switch
and its connections as the same are arranged without the auxiliary calling device.
on the line E E. Fig. 10.
Fig. 9, is a detail sectional elevation, and Fig. 10, a plan view, showing the
preferred construction of this type of instrument when the auxiliary calling device
is employed.
Fig. 11. is a diagram showing parts of the instrument in skeleton and the
various telephone circuit connections of those parts.
Fig. 12, is a detailed view of the mercury chamber as it appears when inclined
in the position assumed in the act of listening.
Fig's. 13, 14, 15, show another modification in the form of the apparatus, and
Fig. 16, a detail of the same.
Fig's. 17, 18, 19, and 20, show modifications in the disposition of the terminals
upon the disc within the cap of the instrument.
Fig. 21, is a diagram of a telephone system embodying the invention, with the
source of current for signalling from subscriber to central located at central.
Fig. 22, shows diagrammatically the connection of a number of the line drop
coils with the generator at the central station.
Fig. 23, shows the system with the use of luminous signals at the central office
in place of switch board drops.
**
Referring to Fig. 1, 1 is the ear piece of a telephone receiver of the approved
type. In the present instance, the type of instrument shown is that known as a
"pony" or watch case receiver," in which the central core 2, and the closing
shell 3, together with the diaphragm 4, constitute the magnetic circuit through
which pass the lines of force, the strength of which is varied by the currents
induced in the receiver coil.5.
The rear or upper end of the core 2, in this figure is provided with a conical or
cup-shaped cavity 6, which serves as the receptacle for a small quantity of
mercury 7.
A knob shaped block 8, of hard rubber or other insulating material is secured
to the top of the magnet shell 3, by the threaded end of the core 2, and this block
is provided with a conical central opening constituting a flaring chamber whose
sides form a continuation of the angle formed by the cavity 6. The sides of this
chamber are preferably inclined at an angle of 45° from a perpendicular line

page_text: through the axis of the instrument, for reasons that will presently appear,
(although any other desirable angle may be used), but, towards the upper portion
of the chamber, are preferably continued in a perpendicular direction, so that
at its widest portion the walls of the chamber are cylindrical.
Nesting within
this chamber and supported by its flange at the-top of the block 8, is a conducting
shell 9, preferably of iron or aluminum or any other metal not attacked by
mercury, whose sides are inclined to conform with those of the block-chamber
but are of somewhat smaller dimensions, so as to leave an annular conically shaped
space between them, which constitutes the mercury chamber 10.
Imbedded in the upper portion of the block 8, with their inner surfaces flush
with the mercury chamber 10, are two contact rings 11, 12, also of iron or other
metal slightly separated and insulated from each other by the material of the
block 8, if the latter is molded with the rings in place, or by separating the ring
of insulating material if the construction shown in Fig. 4, is used.
?
Between the upper ring 11, and the flange of the shell 9, may be interposed
an insulating ring or gasket 13, which serves to seal the mercury chamber when
the shell 9, is secured to the block by the screws 14, 14, (Fig. 3), thereby rendering
the same substantially air-tight and dust-proof. An insulating cap-piece 15,
which screws upon a peripheral thread formed in the block 8, further serves to
hold and enclose the various parts, and together with the block S, forms a con-
venient knob or grip for manipulating and holding the receiver.
Under certain condition which will presently be more fully described, there is
provided a small auxiliary switch-board 10, shown in Fig's. 1 and 3, as within
the upper portion of the shell 9, (and in Figs. 13 and 14, as a disc secured upon
the flange of the shell) to the upper surface of which are secured three contact
springs or surfaces. The contact spring 17, normally rests against the back
contact 18, but is caused to break its connection with 18, and to establish con-
nection with the contact surface 19, when pressure is brought upon the knob or
key 20. This key passes freely through the center of the cap-piece 15, and has
an elongated stem and a button shaped head which serves both as a push button
and as a support for conveniently hanging the instrument, if desired, upon a
suitably shaped hook or fork, 21, shown in dotted lines.
These devices are used as a complementary signalling or signal controlling
device in one arrangement of circuits, but may be omitted in whole or in part
in another arrangement of circuits as will be described, in which the mercury
by shifting its position on the tilting of the instrument operates as the signalling
device.
The flange of the shell 9, which forms the main line terminal, is connected
by means of a small conducting pin or bolt 22, and a wire 23, to the binding
post 24, which forms one of a number that are screwed with interposed bushings,
to one side of the enclosing shell 3. As will be seen by the reference to the
diagram Fig. 5, this binding post 24, connects to the line 59. The bolt 22, as
will be seen passes through one of a number of vertical holes 25, (six in Fig's. 2
and 4), which are preferably located at equal intervals around the knob S, directly
under the contact rings 11, 12. The latter have their outer edges cut away, as
shown in Fig. 6. or may be drilled after assembling and provided with insulating
bushings 26, as shown in the construction illustrated in Fig. 4, in order to permit
of the free passage of the various conducting pins or bolts without touching the
same, at such points as require a through connection between the space above
the shell 9, and the space within the enclosing shell 3. The upper contact ring 11,
connects by means of the pin 27, and wire 28, with one end of the coil 5, of
the receiver. The other end of this coil connects by wire 29, to the binding
post 30, which as will be seen from the diagram view, is in connection with the
secondary coil 31, of the transmitter. The lower contact ring 12, is connected
by a pin 32, (Fig. 2) at the back of the receiver which, like più 27 passes up
from beneath and is connected by wire 33, with the binding post 34, which leads
to the primary coil 50, transmitter 51, and battery 49. When the post is on

page_text: top of the disc or board 16, it may, if desired, screw into the ring directly and
the use of the pin 32, and wire 33, avoided. The binding post 35, which leads
to the magneto 47, and the call bell 48, is, when the auxiliary switch-board 16,
and its connections are omitted as in Fig. 2, directly in electrical connection with
the enclosing shell 3, with which the mercury cavity 6, makes connection.
When the calling apparatus on switch-board 16, is employed, however, an
auxiliary binding post 36, (Fig. 5) is provided, and instead of connecting the
binding post 35, directly to the magnet shell 3, the said post 35, is likewise
insulated from the shell and connected through wire 37, by means of the vertical
connecting pin 38, and wire 39, to the back contact 18, of the spring 17,.of the
switch-board 16, (see Fig. 3). A more direct connection of the post and contact
is permitted when the two are mounted together on the board 16, as shown in
other figures. The spring 17, in turn connects by a wire 40, with the vertical
pin 41, which screws into the magnet casing 3, and is thus in connection with
the mercury 7.
The additional insulating binding post 36, is connected by a wire 42, a vertical
pin 43, and wire 44, (Fig. 3,) to the lower contact 19, that is screwed to the
insulating block 16. Binding post 36, and contact 19, may be in direct connection
with one another when they are both mounted on the board 16, as shown in other
figures. It will be observed that the effect of this arrangement upon the circuit
connections under normal conditions is the same as though the switch-board 10,
were omitted, since owing to the bridging of the contacts 17, and 18, there is
a direct conducting path from the binding post 24, and the shell 9, through the
mercury 7, when resting in the cavity 6, to the magneto binding post 35, while
the auxiliary post 36, under these conditions is practically dead, due to the open
circuiting at its terminal contact 19. The various wires connecting with the
binding posts of the instrument are preferably brought together into a singlo
.flexible cord 45, which is supported within a suitable bracket extension 46, at one
side of the instrument, as shown in Fig. 2.
The operation of the automatic telephone so far as described with now be
.apparent.
Neglecting for the time being the auxiliary calling switch feature, we will
assume that the instrument is used at one end of a telephone circuit provided with
the usual transmitter, induction coil, local battery and magneto calling apparatus,
as indicated in full lines in Fig. 5. If now the telephone is standing or hanging
in its normal position, as shown in Fig. 1, the mercury 7, will rest at the bottom
of the conical mercury chamber 10, within the cavity 6, of the core 2, thus making
connection between the lower end or tip of the main line contact shell 9, (which
is connected with the line through pin 22, wire 23, binding post 24,) and the core
and shell 3, which connect with the magneto directly through binding post 35.
The receiver coil, as well as the transmitter and its local battery are open
circuited under those conditions by reason of the absence of the mercury from
the two upper contact rings 11 and 12. Consequently the connections are in the
condition for signalling, and a call may be sent over the line by operating the
crank of the magneto 47, or an incoming call may be received upon the local
magnet or signal bell 48. When the calling signal has been either given or
received, the receiver is taken by the knob or switch-block- 8, and lifted to the
ear.
The action causes the mercury to at once run to the opposite or upper end
of the switch chamber, as shown in the detail view Fig. 12, breaking connection
with the metal surface of the lower contact cavity 6, and establishing the con-
nection between the main line contact shell 9, at what is now its lowest point,
and the two contact rings 11 and 12, that surround it. In this position of the
telephone, the magneto or calling circuit is cut out and the connections placed
in the proper condition for conversation by the automatic cutting in of the receiver
coil, transmitter and battery. Under the conditions just stated, the main line
circuit is established from the line through the binding post 24, wire 23, pin 22,

page_text: o contact shell 9, through mercury 7, upper contact ring 11, pin 27, wire 0,
eceiver coil 5, wire 29, binding post 30, to the secondary 31, of the induction coil,
At the same
nd from thence to the distant station via earth or line return.
ime the local battery or transmitter circuit is closed from one pole of the
battery 49, through line and binding post 24, wire 23, pin 22, to the contact
shell 9, through mercury 7, lower contact ring 12, pin 32, wire 33, binding post 34,
to the primary 50, of the induction coil transmitter 51, and the other terminal of
the battery 49.
By reason of the conical form and divergent sides of the mercury chamber the
main contact surface, which arrangement forms an important part of the present
invention, not only is a rapid movement of the mercury from one position to the
other obtained, but also the important advantage of providing for a wide range
of permissible inclination of the automatic receiver when held to the ear while
engaged in conversation, without obliging the user to hold it in a fixed position
and without danger of accidental interruption of the connections by reason of
an undue tilting of inadvertent shifting of the telephone which is especially likely
"watch case type of receivers illustrated. This
to take place in the case of the
is primarily due to the fact that when the instrument, is in normal position for
conversation the path or passage over which the mercury or other medium must
How in order to change the connections back from condition for conversation to
normal condition for calling is inclined or directed upwardly.
23
By reference to Fig. 12, it will be seen that it is not even necessary with this
construction to hold the receiver, in listening, with its rear or top portion inclined
below a horizontal line, since the tapering sides of the mercury chamber, which
as already stated, are inclined at an angle of 45° from the longitudinal axis, will
permit a decided forward inclination of the ear piece before the mercury level
reaches the magneto or calling contact surface. This angle, may be, if desired,
increased or diminished, according to the type of instrument used, and the space
towards the rear of the mercury chamber is by preference so reduced in width
that a small quantity of mercury will suffice to spread over a large surface of the
contact rings and thus insure an excellent electrical connection of exceedingly low
resistance thereby greatly improving the clearness of articulation and transmission.
For a similar reason the main contact shell may be provided with a central elonga-
tion or tip at its lower extremity, so as to dip further into the mercury cavity 6,
as shown in Fig. 1. Mercury, either by itself or with the addition of a little
powdered graphite, forms a most reliable and permanent conductor, when used
as a circuit changing medium under the conditions herein shown, and possesses
many advantages as a bridging conductor over the ordinary circuit changing
contacts or springs. The invention is not however, limited to the use of mercury,
as small lead shot or any other finely divided conducting material or fluid may
be used as the circuit changing medium.
To provide for calling the party with whom one is desirous of conversing, and
commenced, without
especially of repeating a calling signal after a conversation
the necessity of hanging the receiver upon a hook switch, or of having recourse
5 to a separate and sometimes distantly located appliance, such as the ordinary
magneto-generator crank or its equivalent the automatic calling feature of the
invention is used. This is also of great use in code signalling for party line
work.
In one way of carrying out this feature of the invention the auxiliary signalling
Okey is used, but the same result may be accomplished without using such auxiliary
key, as will be described further on. The signalling key and connections will
be first described.
Referring to the diagram Fig. 5, the auxiliary or supplementary binding
post 36, is in communication, with any constant independent source of current,
55 through the auxiliary wire or loop 52, (shown in this figure in dotted lines), the
opposite end of this wire or loop, being in this arrangement connected to earth
by reason of the fact that it is joined to the wire leading to the post 35, at a

page_text: point between said post and its junction with the signal bell and magneto 47,
which latter, as is customary, has its coils short circuited when not in use.
The independent source of current is shown as a secondary coil 53, of a small
induction coil or converter 54, whose primary induction coil 55, is in connection
with a generator 56, of alternating or intermittent current adapted to operate
the bell 48, at a distant station. The induction coil 54, may be connected, as
shown, with any convenient alternating-current lighting circuit, or a separate
intermittent current generator, capable of directly furnishing current to a number
of telephone instruments located in the same building, may be installed. For
short distance work or for telephone installations in which a battery calling outfit
is commonly employed, a battery 57, or other source of continuous current, shown
in dotted lines in Fig. 11, may be substituted for the generator 56, and induction
coil 54.
The source of calling or signalling current or energy may be at any desired
point and may even be located at the central office of a telephone exchange and
serve for a large number of subscribers' circuits. This location of the signalling
source is illustrated in the diagrams Fig's. 21, and 23, the latter of which shows
also how the signal may be given by the mere change of position of the mercury
and the use of an auxiliary signalling key or button upon the receiver dispensed
witli.
"
In using the automatic telephone (which in practice is preferably arranged to
lie within easy reach upon the desk or table, with the ear piece down as in
Fig's. 1 and 13, the transmitter being located in a position where it is not in the
way but is at the same time within easy reach of the voice), the person desirous
of establishing communication with central" or with a distant station, simply
reaches out and grasps the instrument by the block S, preparatory to lifting it
to the ear, at the same time pressing the key or button 20, and keeping the latter
depressed for a moment or during the interval required to carry the receiver to
the ear.
The pressure upon the key 20 is made by one or more of the fingers
which are permitted to rest naturally upon the key while assisting the other fingers
and the thumb in holding the instrument in the hand. In this movement of
the receiver a calling signal is transmitted to the distant station from the auxiliary
source 54, or 57, by reason of the opening of the branch 58, of the magneto circuit
at the back contact 18, and the substitution of the auxiliary loop 52, by the closing
of the circuit between 17 and 19, while the mercury 7, still rests within the
cavity 6.
The flow of current may be traced as follows:-
Commencing with the secondary terminal 53, along wire 52, to post 30, interior
connections 42, 43, 44, to contact spring 19, thence to spring 17, connections 40, 41,
and magnet casing 3, to cavity 6, thence through mercury 7, conducting shell 9,
connections 22, 23, to binding post 24, to line 59, through bell or other device
of distant or central station to return wire or ground, across the normally shunted
.coils of magneto 47, through local bell 48, to opposite terminal of the secondary
coil 53.
On raising the receiver to the ear this auxiliary calling circuit is automatically
interrupted by the mercury running towards the rear or base of the cone-shaped
mercury chamber 10, as already described, so that the instrument will then be in
condition for conversation, whether the key 20, is kept depressed or not.
Should
it be desired, as is frequently the case, to repeat a call to "central" while awaiting
an answer to the original call, it will not be necessary, as under the systems now
in vogue, to remove the phone from the ear and to hang it upon a switching hook
in order to restore the calling connection, thus running the risk of missing an
auswer to the original call, but instead a slight momentary inclination or
tilting of the rear portion of the receiver, the pressure upon key 20, having been
naturally maintained in grasping the instrument while engaged in listening, is
all that is needed in order to repeat the call, thus saving a great deal of valuable
time and inconvenience both to the subscriber and to the central station.

page_text: During conversation the pressure is naturally maintained upon the key thus
keeping the branch 52, closed leading to the constantly acting generator so that
on restoring the instrument to normal position the ringing off signal will be
sent through the return of the mercury to the lower portion of the switching
chamber to restore connection between the line and the spring 17.
After conversation is once under way the pressure upon key 20, may, however.
be released. This cuts out the loop or branch 52, and restores the continuity of
the magneto circuit 58. When the instrument is again placed upon the desk, or,
if preferred, hung by the knob 8, or the key 20, upon a suitable stationary fork,
at the end of the conversation, the connections will be in condition to receive
a call upon the bell 48, from a distant station. It will be understood that in
cases where the auxiliary loop 52, is employed the magneto 47, may be entirely
dispensed with, this portion of the drawing being intended to show the application
of the device to existing installations.
On Sheet 2, is shown a modified form of the invention, in which, instead of
bringing the various terminals to binding posts at the base of the instrument,
they are brought to a series of posts at the top of the receiver, with which connec-
tion is made by the conducting cord 45, that passes out through a central opening
at the top of the cap-piece, as shown in Fig. 7. In this form the conducting
cord 45, may itself be a support for sustaining the instrument, while the cap-
piece 15, serves as a protecting hood or cover for the binding posts and conductor
terminals none of which are exposed. In this figure is shown a type of receiver
having a double pole magnet 2, the knob 8, and receiver casing being formed of
one integral piece of hard rubber or other insulating material as shown. The
main line contact shell 9, in this instance forms a lining for the body of the
mercury chamber 10, while the conducting rings 11, 12, are carried by an interior
non-conducting block 60, which at the lower extremity carries a contact ter-
minal 61, which latter is secured to the screw or bolt 62. In the plan view Fig. 8
which shows the terminal arrangement when the auxiliary calling button is
dispensed with, the bolt 62, is directly connected by conducting strip 63, with the
rear binding post 35, thus forming a connection directly to bell 48, and earth or
return from line post 24 by way of shell 9, mercury 7, bolt 62, and post 35,
When the auxiliary switch is used said bolt may be connected to the spring 17,
and thence through the back contact 18, with said post 35, as indicated in Fig's. 9,
5 10, and 11.
As shown in this Figure 8, the binding posts 35, 24 34, and 30, are set around
the block 60, directly above the contact rings, leaving a central space which may
be occupied by a supporting knot in the conductor cord 45. The post 34; screws
directly into the lower ring 12, instead of being connected therewith through a
O wire 33, and pin 32, screwing into the ring as in Fig's. 1 and 3; the others simply
enter the block 60, for a short distance the various terminal wires being brought
up to them from the receiver casing through holes 25, formed in the insulating
blocks 8 and 60. Post 35, connects with tip 61, as just stated and for the same
Post 24, connects by
purpose that it is connected with the cup 6, in Fig. 1.
5 wire 23, with the lower end of the shell 9, by wire 23, passing down through an
opening 25, in the knob or block 8, instead of by a wire 23, and a pin or bolt 22,
screwing into the flange of the shell as in Fig. 1.
Post 30, connects with the end of the receiver coil 5, by wire upon 29, passing
down through another, opening 25, in the block. A terminal pin or screw 27,
50 which is tapped into the upper contact ring 11, from above connects this ring
by wire or pin 28, with the other end of the receiver coil 5.
Fig's. 9 and 10, show the terminal arrangement when the auxiliary signalling
key is used. The key 20, is somewhat enlarged and in the form of a sleeve or
bushing being provided with a hollow central opening having a number of lateral
55 branches 67, through which the conductors of the cord 45, pass to the binding
posts of the instrument. This key has a lower closed portion bearing upon the

page_text: spring 17, which is in connection with the contact 61, through the central
screw 62. The key 20, is formed of two parts, connected by a screw thread, and
as shown in Fig. 4, may be pressed upwardly by a separate spiral spring 68, so
as to relieve the spring 17, of this duty. The key has a free vertical motion
around the conducting cord 45, and is readily manipulated by the pressure of the
fingers which straddle the cord where the receiver is grasped in the hand. The
binding posts.24, 34, 30, terminal 27, and their connections in the plan. view
Fig. 10, are identical with those just described in connection with the preceeding
figures. Post 35, instead of connecting directly with bolt 62, for terminal 61,
by a strip 63, is attached to the back contact 18, on block 16, and is in connection
with bolt 62, through the spring 17, which, as just stated, is in connection with 61,
and normally rests against said back contact when it is free from pressure by
the contact button 20. The auxiliary post 36, instead of connecting to the lower
contact 19, for spring 17, by a wire 42, pin 43, and wire 44, as in the first form
of the invention, is in connection with said contact by being mounted directly
thereon. The circuit connections as they exist under the alternate positions of
the mercury chamber shown respectively in Fig's. 7 and 12, may like-wise be
traced by reference to the diagram view Fig. 11.
When the apparatus is employed for short distance work or under conditions
where a battery instead of a magneto calling apparatus is usually installed, as
already stated, the calling battery 57, wired up as shown in dotted lines in Fig. 11,
will take the place of both the magneto 47 and the auxiliary source 54, and will
serve when connected between the conductors 52, and 58, to automatically perform
its calling functions when the receiver is taken in hand upon entering into con-
versation, as well as automatically "ringing off" when the conversation is ended.
It is to be understood that the invention can be applied to any type of telephone
receivers, as well as to any condition of telephone circuits, and is not limited in
its application to the particular type of receivers or circuit connections illustrated.
The transmitter 51, with its induction coil, and the calling bell or buzzer 48,
might be combined in one and the same apparatus, so as to constitute an integral
part of the portable instrument herein shown and described, leaving only the
circuit connections to the line and battery to be provided for outside of the instru-
ment proper.
Fig's. 13, 14, 15, &c. show the automatic or gravity switch as embodied in a form
of instrument which is self-righting, or in other words is adapted to automatically
assume a position that will cause the switch to restore the circuits to the normal
condition, no matter what position may be given to the instrument in laying it
down after use upon the surface of a table or other object.
Fig. 13, is a sectional elevation of the instrument on the line A, A, Fig. 17.
Fig. 14, shows the same instrument in sectional elevation on the line B, B, Fig. 20,
but with the auxiliary signalling key omitted.
Fig. 15 shows the instrument in partial section upon its side and about to right
itself.
Fig. 16, is a top view of the mercury cup or contact shell of the switch, showing
the position of the holes in its flange.
Fig's. 17 18, 19 20, show in plan the supporting disc or switch-board 16, with
various arrangements of terminal posts and connections adapted for use with
different arrangements of telephone circuits or connections.
The mercury cup or conducting shell 9, for the switch rests by its flange upon
a shoulder of the block or body 8, of the instrument and the disc 16, of insulating
material rests at its edges upon said flange and is secured in position by screws 14,
which pass through holes in the flange and enter the body S. The line post 24,
passes through the disc and at its end sets against the flange so as to be in con-
ducting connection with it. The conical block 60, of insulating material located
within the cup bears at its end the conducting tip or contact terminal 61, which
is tapped to receive the thread of the screw bolt 62, extending vertically through

page_text: .
he disc 16, and block 60, and serving the double purpose of fastening the terminal,
he block and the disc together and establishing an electrical connection between
he tip and the parts within the cap 15. The contact rings 11, 12, are embedded
n the material of the block 60, and the lower surface of the disc 16, being at the
ame time insulated from one another by an interposed washer or ring. The
space between the block 60, and shell 9, forms as before the mercury chamber.
When the supplemental switch device or signalling key is used, the contact
spring 17, thereof is fastened upon the upper surface of the disc by a screw 71,
or for some uses of the instrument may be fastened beneath the head of the con-
ducting bolt 62, as indicated in Fig. 18. In the former case a conducting strip 69,
or other device is used to form a connection between the head of bolt 62, and
a supplemental post 70, seated upon the outer end of said strip, and connection
from the latter to the post 71, is formed either through an external bell circuit
whose terminals are secured to said posts 70, and 71, or directly by a wire indicated
by the dotted line Fig. 17, according to the manner in which the signal bell is
to be included in the circuits.
Spring 18, serving as the upper or normal contact for the free end of the
spring 17, is fastened beneath a shoulder of connecting post 35, upon the disc
of the board 16. The lower or signal contact 19, is similarly connected with a
post 36. The hollow shank or stem to which the knob 20, of the signal key is
fastened by a screw connection, carries as before, the conductor cord 45, leading
to the terminal posts within the cap 15, and the square rectangular lower end of
the shank engages a rectangular opening in the spring so as to hold the shank
from turning and twisting cord 45, when the button 20, is unscrewed from its
shank preparatory to unscrewing the cap 15.
The conducting pin or bolt 32, passes through the disc or board 16, and is
tapped directly into the lower ring 12. Said pin 32, is insulated from the upper
ring 11, at the point where it passes through the latter, by an insulating bushing
as shown in Fig. 14, and its head is connected with the terminal post 34, on the
top of the disc 16, by a strip of conducting material on the upper surface of the
disc 16, as shown in Fig's. 17, 18, 19, 20, secured at one end beneath the head
of screw pin or bolt 32, and at the other end beneath a shoulder of post 34. Or
the conductor may be made in other ways.
The upper ring 11, connects upon the surface of the disc in a similar way by
means of a screw pin or bolt 27, with the conducting bolt or pin 28, which passes
down through disc 16, and the body or case 8, of the instrument and is connected
to one terminal of the telephone receiver coil 5, the other terminal of which coil
is joined to a conducting pin or bolt 29, similar to 28, and bearing at its upper
end the terminal connecting post 30.
In the form of receiver shown in Fig's. 13, 14, and 15, the permanent magnet 73,
is of ring form with two consequent poles and the soft iron cores for the two
coils 5, are of elbow form as shown, and have their horizontal arms fastened to
the magnet at the two consequent points respectively, while their vertical arms
carry the coil. As shown in Fig. 14, the conducting bolts or pins 29, 28, serve
the additional purpose of clamping the magnet in position. The bolts are insu-
lated from the magnet by proper bushings as shown.
The instrument is made self-righting by heavily weighting its lower end and
by giving a proper curve or shape to the sides of the instrument at and near its
base as indicated at 74. The weighting is preferably given by filling in the ear
piece with a mass 75, of heavy metal like iron or lead as shown in Fig. 13, the
effect of which when the instrument is laid down upon its side, or in other position
than the vertical, is to cause it to assume the vertical by rocking upon its curved
side 74, under the action of the weight. By this device the user need pay no
attention to the manner in which he lays the instrument down for it will auto-
5 natically restore itself to such position that the gravity will change the circuits
to the normal or desired condition. The instrument may therefore be placed in
the hands of careless users and at the same time hooks or special supporte for the

page_text: instrument be dispensed with. Obviously the instrument may be weighted by
other means or in other ways to accomplish the same result.
Fig. 14, shows an ear piece of the ordinary form which is interchangeable with
that shown in Fig. 13, and may be used where the instrument is used as part of a
"wall set" in which case it normally hangs suspended from its cord.
The arrangement of terminal connections shown in Fig. 17, permits the local
or subscriber's bell to be included in circuit between posts 70 and 71, so that when
the key is operated to make connection between spring 17, and contact 19, the bell
being still in circuit will ring simultaneously with the transmission of a call by
the subscriber. When this feature is not desired, the posts 70, and 71, may be
short circuited, and the bell may be placed in the connection running from ter-
minal 35, so as to be disconnected and remain quiet when the key is operated
but still be in circuit so as to respond to an incoming call.
66
The equivalent of short circuiting 70, and 71, is accomplished by the arrange-
ment shown in Fig. 18, wherein spring 17, is secured directly to bolt 62. If a
bridging" bell 48 is used as indicated at the right of diagram Fig. 21, (that is
a bell connected across the wires 59 and 79 leading to the line post 24, and the
return wire post 30), terminal post 35, and spring 18, may be dispensed with as
indicated in the diagram, and the disc may then have the simplified arrangement
shown in Fig. 19.
The disc shown in Fig. 20, has the auxiliary push button or key omitted and is
adapted for use where the bell is to be connected in the wire leading directly from
tip bolt 62, as indicated at the left of diagram Fig. 23. In this case the bolt
carries or is directly connected with a terminal post like 35, Fig. 14, for attach-
ment of one of the wires of the cord 45.
The diagram Fig. 21, shows the invention as applied to an exchange employing
annunciator and clearing out drops and without interfering, with the use of the
existing central source of energy for transmitting signalling current from central
to the called subscriber over his line. The diagram also shows the improvement
which consists in dispensing with the use of sources of signalling current at the
various subscribers' stations for permitting them to call the central office, and in
centralizing the energy used for this purpose at the central office or other desired
point common to a number of subscribers.
In this improvement the subscriber operates the line and clearing out signals
at the central office over a wire used in conversation but the electric source con-
trolled by him at his station for this purpose, instead of being located at said
station, is at the central office.
It will also be observed from the subjoined description that the system shown
embodies the usual metallic line circuit for conversational purposes and that the
signalling from subscriber to central and vice versa, is done by grounding said
metallic circuit at the subscriber's station and at the central office, the generator
being in the ground at the latter point and serving to supply any number of
circuits.
In the diagram two subscriber's stations only are shown, the one at the left
being provided with the automatic telephone having terminal posts and connections
such as are furnished by a disc like that of Fig. 17. The bell 48, being connected
between posts 70, and 71, rings both on outgoing and incoming calls. The one
at the right has an instrument furnished with a terminal disc like Fig. 18, and
the bridging bell 48, being connected across the two main line posts 77, 78, rings
on call from central, but is silent on outgoing calls.
76, at both stations, is a main ground post to which connection is made from
post 36, thus providing a connection which, when completed, furnishes a circuit
for the ringing source of energy by which the subscriber calls central or operates
the clearing out signal. The station at the right requires no upper or back contact
spring 18, owing to the fact that the bridging bell is used. In the system illustrated
a second line wire 79, for each station provided a metallic return as usual in the
art. The secondary 31, of the transmitter induction coil is connected to the main

page_text: st 77, of the line 79, instead of being connected to a ground return
d 11. Battery 49, primary 50, and transmitter 51, are connected to main
ne 59, by main line post 78.
Briefly the apparatus at the central station comprises the following parts of
e usual construction, but in addition thereto a source of energy in proper connec-
on to enable it to come into action and operate the line and clearing out drops or
ther signals when the subscriber's instrument completes the proper circuit.
Une pair only of connecting plugs and their accessory appliances are shown,
ith a corresponding pair of spring jacks to which the subscriber's lines are
onnected. The tips 80, of the plugs are connected through one of the cond:1c-
ers 82, of the usual flexible cord circuit and the sleeves 81, of said plugs are
onnected by the other conductor 83, of the cord circuit. Tips 80, when the plugs
re inserted, register with springs 84, of the spring jacks with which are connected
he main lines 59, and sleeves 81, register with ring 85, to which the line returns 79,
are connected, thereby connecting the subscriber's circuits for conversation.
86, indicates the usual ringing or calling key by which a subscriber is called,
and 187, the usual calling generator from whose terminals circuits run to contacts
of the ringing keys adapted to be engaged by springs 87, joined to the contacts 80,
81, of the plug. When either key is operated, after insertion of the plug into
the spring jack it disconnects the springs 80, 81, from the contacts through which
they are joined to the cord circuit and connects them to contacts leading to the
generator 187, thereby causing current to flow from the latter over the circuit 59,
79, and subscriber's bell 48. A listening key 88, for the cord circuit has two
contact points or anvils connected respectively with the conductors 82, 83, as
shown, and two corresponding contact springs connected respectively with the
operator's listening telephone 89. When the plunger key is allowed to rise, it
brings the contact springs and anvils into engagement, thereby connecting the
telephone to the cord circuit.
On each plug is a ring or sleeve 90, entirely insulated from all other portions
of the plug and adapted to register with two springs, as shown, to connect them
together when the plug is inserted in the jack. One of said springs connects
directly to earth or a common return while the other is connected through a
restoring coil 91, or the corresponding line annunciator or drop with a wire which
is in connection with the grounded generator 92, common to the circuits. The
5 connection of the springs by the ring 90; allows current from generator 92, to
energize the restoring coil and return the drop, as well understood in the art.
Test thimble 93, joined to wires running throughout the switch-board and in
connection therethrough with the test thimbles and jacks of other sections fur-
nishes a busy" test. Each is connected at its own section with the spring which
is grounded through sleeve 90, when the plug is inserted. When the operator
at any other section of the board touches the test thimble at her section with the
tip 80, of her plug, a click in her telephone which has a ground connection 94,
from the middle of the telephone coil indicates "line free" because generator 92,
finds circuit through thimble 93, tip 80, cord circuit 82, and contacts of listening
45 key. If, however, a plug has been inserted into the spring jack of the line wanted
at any other section of the board, the current is short circuited from her telephone
by the plug sleeve 90, which forms direct connection to earth from the test sleeve
through the springs engaging sleeve 90, as stated. Silence being then the result
of the test, the operator will know that the line is busy.
56
95, is the actuating coil of the usual clearing out drop or annunciator, and 96
the restoring coil thereof. The former is a high impedance coil connected acros
the two sides of the cord circuit 82, 83, and comes into action when eitber of the
two connected subscribers rings off. Coil 96, comes into action when the operato
"listens in" by operating her key 88, thereby bringing insulated spring 97, con
55 nected to coil 96, into contact with an anvil connected to earth, and thus com
pleting the circuit of a generator 98, which is connected to coil 97, and grounde
shown

page_text: -
The line annunciator or drop is of the self-restoring 'character: Its liné
coils 99, operate to cause a drop to be displayed when the subscriber calls central;
but said coils instead of being connected across the line wires 59, 79, and carrying
current from a generator, are-connected between one pole of central generator 100,
which may be common to a number of drops and one or both of the
lines 59, 79, while the opposite pole of said generator is connected to earth or
suitable return. The generator may be a' battery; motor generator or power driven
magneto as desired, and serve for any number of lines, as indicated in Fig. 22,
where a number of line drop coils are shown' tapped onto a bus wire fed by the
generator 100.
.
It is preferable to 'use a motor generator or battery supplying direct current,
since possible inductive disturbances are thereby avoided.
The same generator may also supply current to operate the coils 95, of the
clearing out drop. For this purpose it is connected to the side 83 of the cord'
circuit or otherwise connected with one terminal of the several coils 95; of the
exchange, their opposite terminals being connected with the side 82, of the cord
circuit which connects with the plug terminal that is in connection with the side
of the subscriber's circuit which is used in ringing off.
In this case the coils 99, should like the coils 95, be high impedance coils to
prevent the short circuiting of the voice currents.
Right hand subscriber is shown as having called central and the latter is ring-.
ing up left hand station by operating the proper ringing key .86.
The general operation is as follows:-In grasping and lifting his instrument
to the ear; subscriber at the right hand station closes ringing contact 19, thereby
operating the line drop by current from generator. over the following circuit:-
From 100, line coil 99, line wire 59, shell or cup 9, mercury 7, contact 61, bolt 62
spring 18, contact 19, post 36, 76, to earth and back to generator 100. The act
of lifting the instrument also causes the mercury or gravity switch to change to
position and change the circuits to condition for conversation. Central operator
then shoves one plug of a cord into a line jack of subscriber calling, one effect
of which is to restore the line drop by completing a circuit through restoring coil 91,
as follows: From generator 92, to coil 91, and by springs bearing on plug
collar 90, to earth and back to generator. The operator then throws listening
telephone 89, by means of key 88, into the circuit 59, 79, and obtains the number
of line wanted from subscriber A, which may be left hand station or subscriber B.
Desiring to call subscriber B, the operator uses the other plug of the cord circuit
and after testing by means of tip 80, as explained, inserts plug into line jack
of subscriber wanted and operates ringing key 86, to throw current from gene-
rator 187, into circuit 59, 79, thereby ringing the bell of subscriber wanted, over
the following circuit at his station:-From line 59, cup or shell 9, mercury 7
'contact 61, bolt 62, post 70, bell 48, post 71, spring 17, back contact 18, line 79
and back to central and subscriber on picking up his instrument places the circuit
of his own instrument in condition for conversation automatically, the line circuit
being now from 59, to shell 9, mercury 7, contact ring 11, coil 5, post 30,
secondary 50, and to main line 79. The ground connection by tip contact 61,
bolt 62, bell 48, spring 17, and contact 19, is at the same time broken by the flow
of mercury away from the said tip, but prior to this change of connection there
will be a momentary ground from line 59, by shell 9, tip 61, bell 48, spring 17,
and contact 19, which will as in the case of the subscriber at the right, cause the
line coil of the drop to act and which would be effective in the same way in calling
central if subscriber at the left were the first to call.
In ringing off either subscriber on laying down his instrument causes the switch-
ing devices to automatically change the connections and a circuit to be established
through the clearing out drop coil 95, as follows:-From generator 100, to cord
circuit 83, coil 95, cord circuit 82, tip 80, line 59, shell 9, mercury 7, tip 61,
bolt 62, spring 17, contact 19, ground and back to generator.

page_text: In "listening in" to ascertain whether conversation is misne
perator automatically restores the clearing out drop by the action of the coil 96;
before explained.
::
As will be observed the work is done without interfering with the use of the
dinary central office equipment, and the signalling to and from central and ring-
g off is accomplished entirely by an automatic action within the receiver and
y the use of centralized sources of energy only
Diagram Fig. 23, shows the invention as applied and carried out in connection
ith a telephone system employing luminous signals at central and by the use of
entralized energy.
The lines 59, 79, connect respectively with the springs 84, 84, of a spring
ack which are engaged respectively by tip 80, and collar or sleeve 81, in the plug
aid tip and collar being respectively connected with contact springs of a ringing
ey 86, and by inner anvils of the latter with the two sides 82, 83, of the cord circuit,
ach of which sides contains two sections 112, of a divided repeating induction
coil. Lines 59, 79, are also normally connected through the normally closed
pack contacts of a switch 104, with relay 101, and a battery or other generator 114.
Relay 101, serves to close local circuit 103, to illuminate a line signal lamp 113,
when the lines 59, 79, are connected by the automatic gravity switch within the
A relay 102, operates to open
receiver in tilting the same to lift it to the ear.
the switch and to extinguish said lamp. Bridged across the conductors 82, 84,
at a point between the divisions of the repeating coil is the supply battery 105,
supplying energy to the lines 59, 79, and the transmitters 51, at subscriber's
stations. One terminal of battery 105, is grounded for test purposes. Another
bridge contains the operator's telephone 89, listening key 88, and transmitter.
One or both the outer anvils of the ringing key may connect with the calling
generator 100, so that the current therefrom will flow over both wires 59, 79, when
proper connections exist at the subscribers' stations, and through the ground con-
nection containing the bell at the subscriber's station. Their inner anvils connect
to the cord circuits. Said generator is similarly connected to all the ringing key,
contacts of the station. The plug of the jack carries as usual the insulated
sleeve 110, adapted to connect with the thimble 109, which latter is connected to
ground through the relay 102, which operates to extinguish line signal lamp by
opening the double pole switch 104.
In each division of the cord circuit 83, there is a relay magnet 106, whose
armature, when the magnet is energized closes the circuit of battery 107, through
a relay magnet 108, the armature of the latter serving, while attracted, to open
The circuit of relay
the branch maintaining the clearing out lamp 111.
battery 107, after passing relay 108, is continued through the insulated sleeve 109,
and restoring relay 102, to earth and back to relay battery 107.
In circuit with one of the clearing out lamps 111, for each pair of plugs, is a
relay magnet 115, which controls the local circuit of a supervisory lamp. 116, by
closing circuit on its front contact, thus causing both lamps 111, 116, to be lit and
extinguished together.
In the apparatus at the subscriber's station the signal bell 48, is in the direct
connection to earth from post 35, joined to the tip contact 61, of the automatic
gravity switch. The telephone transmitter 51, of the subscriber is in the direct
line circuit and operates by varying the contact to control the action of the central
energy talking battery 105, connected to the cord circuit by which two subscribers
are joined.
The upper contact ring of the mercury switch is connected as already explained
to the coil 5, of the telephone receiver, the opposite terminal of the latter being
connected to the post 30, and return line 79. The lower contact ring 12, need
have no connecting post 34, or may be dispensed with, or the post if it exists
5 may be left unconnected in this use of the instrument..
The bells 48, being grounded from the top contact 61, will obviously ring only

page_text: No
when central transmits a call through pressure on the ringing key SG.
auxiliary push button is employed in the arrangement shown, the contact ring 11,
serving by reason of the connection and arrangement of devices described, as the
signalling contact, since in addition to automatically changing the circuits to
condition for receiving and transmitting conversation, it operates by closing con-
nection from one line 59, to the other 79, to perform the signalling function by
completing the circuit of the battery 114, at the central station.
The diagram shows two subscribers connected at the central exchange. Right
hand station has called central by lifting the receiver, thereby causing the gravity
switch within it to shift position and, by completing circuit to the battery 114,
at ring 11, to cause lamp 113, to light. Central has responded by plugging in
one end of the cord circuit into the spring jack of the right hand station, thereby
extinguishing calling lamp by completing circuit of battery 107, through contacts
of relay 106, which have been energized by the battery 105, on insertion of the
plug, coils of relay 108, sleeve 110, of the plug, test contact ring 109, and relay 102,
which latter operates to open the double break switch 104.
In addition the relay 108, by opening the branch containing the clearing out
lamp 111, keeps the latter extinguished until the subscriber by laying down his
telephone causes the mercury switch within the same to shift to the position shown
at the left hand subscriber's station thereby opening the circuit of battery 105,
at ring 11. The relighting of the lamp gives notice that the subscribers are
through talking. Central having ascertained from right hand station by bridging
in the head phone 89, that connection is desired with the left hand station, has
inserted the other plug of the cord circuit into the spring jack of the latter, and
has, by pressing the ringing key 86, transmitted calling current from ringing
battery 100, over springs and outer anvils of the ringing key to line 59, thence
through shell or cup 9, mercury 7, tip 61, and bell 48, to earth. When subscriber
to the left picks up his receiver the switch within the same completes the talking
circuit of battery 105, through the two halves of the central repeating coil the
other half of which acts as the secondary.
No local induction coils or other talking batteries are used at the subscriber's
station, the transmitter being in series with the receiver coil, nor are there any
condensers required at the sub-stations as would be the case if the bells were
bridged across the lines 59, 79, in the manner sometimes employed.
From what has been said it will be evident that, by means of the invention, a
simple, rational, self-contained and effective telephone system of great flexibility
is provided that reduces the number of the manual operations required by, and
affords many other advantages over, the existing methods of conducting telephonic
communications and the more or less complicated apparatus for practicing the
same, inasmuch as, by means of the automatic telephone only a single movement of
the hand, (leaving the other hand entirely disengaged) and that movement
promptly and almost unconsciously performed, in a most natural and instinctive
manner without any necessary previous training, is all that is required to com-
mence, carry on, and finish a conversation.
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
1. In a telephone apparatus a portable receiving instrument or ear piece embody-
ing or carrying automatic switching devices adapted to change their connections
in an automatic manner through the act of grasping the instrument and applying
the same to the ear, and combined with circuits and generators as described, so
that the calling, circuit changing, and ringing off functions are automatically
performed in the act of taking up and applying the receiver to the ear and then
laying it aside after use.
2. In an apparatus for telephonic communication, a single portable apparatus

page_text: receiving
embodying the signal controlling device and circuit changing and
nechanism, of a telephone station combined as described to successively perform
heir signalling, circuit changing and receiving functions by the act of grasping
and lifting the said apparatus to the ear.
3. In an apparatus for telephonic communication, a single portable instrument
comprising a telephone receiver bearing a self acting or gravity switch that auto-
matically changes the connections from condition for receiving the signals to con-
dition for conversation, and also a signal controlling device for calling the distant
station, adapted to be grasped or engaged by the hand when taking hold of the
instrument, whereby, as described, the calling, circuit changing and receiving
functions are successively performed by and in the act of grasping and lifting the
said apparatus to the ear.
4. In a telephone apparatus, a telephone receiver or ear piece carrying a gravity
circuit changing switch together with a complementary signalling switch or circuit
controlling device adapted to operate in conjunction therewith, all combined and
constructed as described to perform the calling, circuit changing, receiving, and
ringing off functions, by the act of grasping the receiver, applying the same to
the ear and returning or permitting it to return to its normal position when the
conversation is ended.
5. In a telephone system the combination with the local call bell and a magneto-
generator or other normally inactive source of calling current, of a switch device
for normally maintaining the local circuit closed through said bell so that the
latter may be operated by a calling signal transmitted from such normally inactive
source, and an independent or auxiliary active source of calling current and a local
circuit closing key therefor designed and adapted to transmit a calling current
and to operate the call bell when manipulated while the said switch is in its normal
condition, substantially as set forth.
6. In a telephone system, the combination with the signalling circuit and a
switch device for normally maintaining said circuit in a condition to be responsive
to a calling current sent over the same from a distant and normally inactive source,
of a continually active auxiliary generator, and an auxiliary key or push button
arranged to be operated in conjunction with said switch device for including said
auxiliary generator in the signalling circuit, substantially as set forth.
7. In a telephone system, the combination with the signalling circuit, of a
continually active source of current therefor, normally disconnected, and means
located within or carried by the receiver and operated by the action of inclining
or tilting the receiver while the same is grasped by the hand and held in position
for listening as described, for operatively including the said source in the signalling
circuit and thus repeating the call while awaiting an answer to the original call.
8. In a telephone system, the combination of a continually active source of
signalling current normally out of use combined with a receiving instrument
carrying an automatic gravity switch and connections as described whereby
through the action of inclining or tilting the receiving instrument while held in
position for listening the said active source of current may have its circuit closed
and the call may thus be repeated while awaiting an answer to the original call.
9. In a telephone system, the combination with the local call bell, of a switch
device for normally maintaining the local circuit closed through said bell so that
the latter may be operated by a calling signal sent from a distant point, a source
of calling current, and a local circuit closing key therefor designed and adapted
to transmit calling current when manipulated while the said switch is in its normal
condition.
10. In a telephone system, the combination with the signalling circuit, of a
switch device for normally maintaining said circuit in position to be responsive
to a calling current sent over the same from a distant source, a continually active
5 auxiliary local generator, and an auxiliary key or push-button arranged to be
operated in conjunction with said switch device for including said auxiliary gene-

page_text: rator in a signalling circuit through said switch'device while the same is in its
normal position.
11. A telephone receiver having a gravity circuit changing or switching device,
and having a calling key connected to said switching device, as described, so as to
be rendered operative when said switching device is in one position and to be
thrown out of operative condition when said switching device or the receiver
containing the same is in another position, substantially as and for the purpose
set forth.
12. An automatic telephone instrument comprising in a single portable struc-
ture, a receiver, a circuit-changing switch adapted to be automatically operated
by the change in position of the receiver from the calling to the listening position
and vice versa, and a key or signalling device arranged to be operated for trans-
mitting a calling current by the hand which grasps the receiver, substantially as
set forth.
13. A telephone receiver bearing a mercury chamber, a series of contact surfaces
within said mercury chamber, connections between said contact surfaces, and a
series of binding posts carried by or secured to the body or frame of the receiver,
and a calling key or switch interposed between one of said contact surfaces, and
one or more binding posts, connected with or included in the sigualling circuit,
substantially as and for the purpose set forth.
14. A telephone instrument having a receiver coil and diaphragm and a casting
therefor, an insulating knob at the back of said receiver casting containing an
automatic gravity circuit changing switch and an auxiliary signal or calling
device, and an enclosing cover or cap piece for said device containing a key or
push-button for operating the same, substantially as set forth.
15. In a telephone receiver, the combination of an inverted cone shaped cup.or
shell having a cylindrical upper or base portion and serving as the receptacle
for a fluid conductor, an insulating plug or stopper having a lower portion sub-
stantially conforming in shape to and entering said conducting shell and carrying
supplementary conducting terminals, a fluid or similar circuit closer, as described,
a circuit closing switch mounted upon the upper or exterior portion of said insu-
lating plug, an enclosing cover for the circuit closing switch and receiver ter-
minals, and a key or button projecting through said enclosing cover for operating
the circuit closing switch, substantially as set forth.
16. In a telephone receiver, the combination with the knob or casting containing
the gravity switch and calling contacts and their connections, of an enclosing
cover or cap-piece containing a movable key or signalling button operating upon
said contacts, substantially as set forth.
17. In a telephone receiver, the combination with the knob or casting containing
the gravity switch and calling switch contacts and the terminal binding posts,
of an enclosing cover or cap-piece for the same, and an operating calling key or
button carried by the said cap-piece and having an opening or openings for the
passage of the conducting cord leading to the binding posts.
18. In a telephone receiver, the combination with the calling switch or circuit
closer having a front and back contact, the receiver binding posts and their
enclosing cover having a central opening, of the combined conducting cord bushing
and operating key for said calling device movable within said opening, substan-
tially as set forth.
19. In a telephone receiver, the combination of an inverted cone shaped con-
ducting cup or shell having a cylindrical upper or base portion and serving as
the receptacle for a fluid conductor, an insulating plug or stopper having a lower
portion substantially conforming in shape to and entering said conducting shell
and carrying supplementary conducting terminals, a circuit closing switch mounted
upon the upper or exterior portion of said insulating plug, an enclosing cover for
operating the circuit closing switch, substantially as set forth.

page_text: 20. An automatic gravity switch weighted in the manner described so as to
be self-righting when laid upon the surface of a table or other object.
21. An automatic gravity switch contained within a telephone receiver and
controlling the connections thereof, and weighted so as to be self-righting when
laid upon the surface of a table or other object.
22. In a telephone exchange system, a block or casing carrying a gravity switch
adapted to change the circuits from condition for receiving a signal to condition
for conversation and formed and weighted as described to assume an upright posi-,
tion when laid upon its side.
23. In a telephone exchange system, a self-righting signalling and circuit
changing device adapted to assume its normal position under the influence of
gravity when laid in any position upon the surface of a table or other object.
24. The signalling button having a screw connection with a hollow shank
adapted to carry the conductor and held against rotation by its engagement with
the shiftable element in the signalling key, as and for the purpose set forth.
25. In a telephone exchange system having a clearing out drop connected across
the cord circuit, the combination of a grounded generator connected to said circuit,
and a telephone receiver at the subscriber's station embodying an automatic
gravity switch adapted to complete a ground connection when the instrument is
placed in its normal position..
26. In a telephone exchange system employing line drops at the central, a central
source of energy in normally open circuit, a subscriber's receiving instrument
carrying a gravity switch adapted when the instrument is lifted to the ear to com-
plete a ground connection at the subscriber's station for the central source of
energy whereby the line drop is operated.
2
27. In a telephone exchange system, the combination with line drops, and a
central source of energy in the ground connection from subscribers lines, of auto-
anatic subscribers switches contained in a telephone receiver casing and adapted
to complete the ground connection from the subscribers line when the instrument
is, lifted to the ear.
28. In a telephone exchange system, the combination with line drops or other
signals. at the central station and a source of energy at said station for operating
the same, of subscriber's instruments having automatic gravity switches embodied
in the telephone receiver and adapted to complete a connection whereby the line
Signal may be operated when the instrument is lifted to the car.
29. In a telephone exchange system, a centralized source of energy grounded at
the exchange and connected to the operator's ringing keys, in a combination with
metallic subscribers' circuits each having a receiver carrying an automatic gravity
switch that completes a ground connection in one position of the receiver and
unites the two sides of the circuit in the other position.
30. In a telephone exchange system, subscribers' circuits each having a self-
righting telephone receiver bearing an automatic gravity switch for changing
the connections from condition for receiving a signal to condition for conversation.
31. In a telephone exchange system, the combination with a central exchange
having sources of energy common to the circuits for receiving a call from or trans-
mitting a call to a subscriber, and subscribers receiving instruments each fitted
with an automatic gravity switch, adapted to change the connections from con-
dition for receiving a signal to condition for conversation when the instrument
is lifted to the ear.
32. In a telephone exchange system, the combination of an exchange having
sources of energy common to the subscribers lines for receiving and sending
signals and for conversation between subscribers, and a telephone receiver bearing
a gravity switch that automatically transmits a call and changes the circuits from
condition to receive a signal to condition for conversation in the act of lifting the
instrument to the ear.
33. In a luminous signal telephone exchange system, the combination with the
metallic subscriber's circuits normally connected through a generator at central,

page_text: and a grounded source of energy at central, of subscriber's telephone receivers each
carrying an automatic gravity switch adapted to complete a ground connection
at the subscriber's station when the instrument is out of use and to connect the
two sides of the metallic circuit when the instrument is placed to the ear.
Dated this 11th day of December 1899
For the Applicant,
ELIAS ELKAN RIES,
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent,
For the Applicant,
ELIAS ELKAN RIES,
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.