Improvements in Apparatus for Electric Signalling, and Adjuncts thereto.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Electric Signalling, and Adjuncts
thereto.
I, FELIX BENEDICT HERZOG, Ph.D., of 1123, Broadway, New York, U.S.A.,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
The object of this invention is to improve various parts of a system of automatic
signalling or communication.
The various elements included in the system I design for use either separately
or in connection with less than the entire number of the other elements or in
a system in which all are used simultaneously; the degree of aggregation
depending upon the commercial result required in each instance.
As a whole
the system comprises transmitting instruments called transmitters at each of
several stations which with respect to one or more common stations are called
sub-stations and at the common station or stations suitable indicating and
receiving mechanisms controllable either from a sub-station alone or from this
station jointly in co-operation with apparatus located at other sub-stations or at
the central station or at auxiliary stations.
Transmitter. Although many of the points of improvement are adapted for
use with transmitters which in some respects vary widely from the one herein
selected as a typical embodiment some of the features are to be considered as
applicable only to a transmitter of what I call the sliding arm type of double
signal transmitter. A form of such transmitter, improvements upon which are
herein set forth as a part of this invention, is, generally speaking, organized
as follows:
A motor of suitable character, such as a spring driven clockwork, controls
the rotation of a shaft or arbor bearing a circuit break wheel and a manipulative
setting device which enables an operator to point at any indication upon a
co-operating dial plate the latter having these indications arranged in radial
columns. This setting device includes an arm adapted to telescope or slide
within a bearing, called a sleeve, mounted upon and pinned to the shaft over
the dial and adapted to guide the arm so that one end thereof may be drawn in
toward or away from the central shaft which bears it and which projects from
the centre of the columns of indications forming the dial, and in this manner,
this end of the arm may be set so as to coincide with any desired indication.
Variable abutting or stopping devices are arranged to limit the extent of rotation
of the arm at various points according to the extent to which it has been drawn
out of the sleeve, these devices collectively being called a rib," and the break
wheel is arranged to co-operate with the arm and these stops in such manner
that distinguishable sequences of impulses are produced in a co-operating circuit,
This break wheel
for every possible position and range of motion of the arm.
co-operates with a contact terminal or brush, so that teeth in the wheel make
contact therewith. the signal circuit passing through this point of contact.

page_text: When the operator at the sending station "sets" this apparatus at a certain
indication, provision is made to prevent the clockwork motor which is wound
by the act of rotating the arm to the chosen column, from unwinding immedi-
ately, and this provision includes a simple lock cam in the gear work.
The dial columns bear words in each space, so that, as the arm is rotated any
chosen distance from the central support it will pass over an indication in each
column traversed. An electro-magnet controls this motor, and is in turn con-
trolled from the distant station. In order to permit the operator at the trans-
mitting station to notify the receiving station operator that the apparatus is in
condition to be so controlled from the said second station, an adjunctive push
button is arranged at the transmitter, and this includes certain metallic parts
brought together by the act of depressing the button. The circuit break wheel
is mounted upon the shaft just under the dial and sleeve.
The clockwork is so arranged that if the pointer arm has been accidentally
moved, during setting, further than desired, the clockwork may be unlocked so
as to run down just enough to permit the arm to be brought back to the desired
column.
Among the improvements I have made upon the above described organization
are that the train of movement is mounted upon a front plate and that simple
provision is made whereby this aggregation of plate dial and movement or train
may be readily withdrawn from its co-operating back plate so as to permit of
easy inspection and repair and of the substitution of a second machine on a sup-
port or back plate of any machine in use thus making it possible when after
removal of a defective operating transmitter the fault is found not in the con-
nection wires but in the apparatus itself to substitute another machine. I have
devised many ways of securing this desirable result and specify merely as one
a back plate to which may or may not be permanently attached the necessary
electrical connections and which bears attachments or adjustments for locking
the transmitter in place--such attachments being controllable after the apparatus
is locked in place. I mention specifically a form in which the necessary wire
terminals are permanently attached to metallic contacts mounted upon an insu-
lating block on the back plate and so placed with reference to co-operating
terminals forming a part of the box itself that the engaging devices or attach-
ments such as pins screws cams levers and so forth may be made to lock the
transmitter in place and at the same time to lock into operative contact the
appropriate and respective contacts on the walls plate and box. Moreover where
the transmitter is of the character described above thus including an adjunctive
push button I prefer to arrange the contacts in the box in close connection elec-
trically, with the metallic parts controlled by the act of pushing. I claim
moreover devices adapted to secure the transmitter in place in a wall of any of
the types ordinarily used in hotels so arranged that the transmitter movement
would be sunk in into the wall to the desired degree and I claim a construction
particularly which will permit this portion of the work to be done economically
under the average conditions of building and to this end I make the parts so
that one may he put up before the plastering is finished or if desired at any
time thereafter without requiring a degree of care greater than that which cheap
labour may be counted upon as affording and a second piece is put on later and
combines a box-like equivalent for the wall plate already described and bears
the insulated terminals as well as the devices which co-operate with parts on
the transmitter to lock the aggregation together and is also arranged so as to
make it easy to correct any errors which may have been made in the setting of
the first part thus providing for an orderly appearance of the completed appa-
ratus. Among the adjustments thus required ordinarily will be one in a line
in and out from the wall to provide for variations in the thickness of the plaster
and another in the plane of the wall to provide for variations from the perpen-
dicular. It is desirable that the transmitters when mounted in this manner
should be insulated from the damp wall to a reasonable degree and so I prefer

page_text: to form my inner box or pocket so that suitable insulating portions will receive
the second piece thus making it possible to make the connections and locking
devices between the transmitter and second piece entirely of metal which is
much neater cheaper and more convenient than any other arrangement I have
been able to devise for this purpose; the second piece I prefer to make with
one extension for the locking features and with three extensions to perform
the levelling and adjusting referred to. I also mount the break wheel at the
bottom of the shaft so that when the box is removed for inspection as described
the operative portions of the break wheel will be in plain view;
I also arrange
the break wheel so that an insulating plate is attached to it in such manner
that no matter how severe the tension on the contact may be the point of the
brush cannot drop into the space between the two teeth so as to make a longer
contact than requisite and 1 also claim the contact brush which while locked
within a certain range of movement toward the centre of the wheel by the pro-
vision described will also be locked in the reverse directon by an adjustment
which permits just play enough for the necessary adjustments but cannot be
moved beyond the range of resiliency or tendency by any careless manual experi-
ment or adjustment on the part of the inspecting operator. The break wheel
moreover is arranged so that it can be removed from the hub or arbor without
requiring the disadjustment of the dial and sliding arm. I also claim the
magnet mounted upon the framework of the wheels. I also claim an improve-
ment in the device for holding the sliding arm in the desired lateral position
this improvement consisting in a plunger acting at right angles to the arm.
also claim an arrangement whereby the arm may be rotated back and forth at
will during the preliminaries of selecting the desired word and as this rotation
would necessarily wind up a spring I employ devices for neutralising this
action so as to prevent undue strain upon this spring and as preferred construc-
tions for this purpose I specify a friction plate or barrel together with means
for taking up wear therein and a single pinion or ratchet broad enough to engage
with two clicks engaging respectively for movements in a reverse direction;
and I specify particularly that according to the arrangement referred to the
turning back is not only much simpler but the wound up movement does not
require to be permitted to run down thus saving wear and being less noisy. I
also specify that instead of the cam form of lock in the old organization
described, I arrange my cam with a pin or projection which co-operates with an
extension to the armature acting both as a hook and as an abutment limiting
its range of movement and I also claim combining with the magnet either as
a separate armature or with the main armature a tapping device which prefer-
ably co-operates with a gong so that return signals may be received upon the
gong and when, as in the preferred form, the main armature controls the gong
ringing, I claim the adjustment required to prevent a tap of the gong at each
closure of the circuit during the rotation of the break wheel thus saving the
annoyance of the sounding of the gong during the normal operation of the
transmitter.
In connection with the sliding arm I claim a square or angle cornered main
arbor as a support for the sleeve which bears the sliding arm and I also claim a
sleeve which acts as a guide to the arm for a greater distance than the diameter
I also claim a
of the part which connects the arm support with the movement.
device co-o; erating with the pointer to direct attention which end is to be used
and also claim a pin projecting downwardly at right angles from the pointer and
serving both to specify the desired word and to engage with the variable abut-
ting device which I call the rib. This rib I also claim when arranged
independently of the outer frame so that it may be adjusted without reference
thereto and also when formed of narrow material which permits the pointer to
be rotated with the loss of less than one space and when both edges of the rib
serve to limit the motion of the pointer in harmony with its position from the
centre.

page_text: In the old organization described a word is arranged in each space. I have
found that a very great improvement may be made in the trustworthiness of
the mechanism it instead of setting signals at every possible point arrange
the signals so as to alternate or stagger with blanks in an arrangement analagous
to that of a chess board. In this way if any error is made in setting the trans-
mitter to a word adjoining the one intended; the receiving operator will notice
that an error has been made and he cannot be deceived as he would be if the
same error were made on the old machine referred to. This same general
arrangement will make it possible to modify the signals received still further
so that those signals which are formed after the large tooth has passed under
the brush shall be arranged to duplicate or check the signals formed during the
first part of the operation. I also arrange the dial itself so that it may be
inserted or withdrawn for the purpose of changing the indications without taking
off the sliding arm or other parts upon which the adjustment depends with the
risk of spoiling that adjustment. I do this either by making the dial in sections
or by making it more or less fan shaped and in this event as in other cases I
prefer to cover the actual printed dial with transparent material such as cellu-
loid or its equivalent which by reason of its flexibility will permit the insertion
of a new dial without great allowance of space.
I prefer to make the connections within the box so that the magnets and the
brush are arranged in series thus preventing a complication in, testing in the
event of certain cross connections.
As thus far set forth the specific improvements only have been mentioned. I
propose moreover to combine with the transmitter described or with any other
variable signal transmitter a coin controlled device adapted to prevent the partial
or complete operation of the transmitter without the deposit of a suitable coin
and I propose to do this electrically or mechanically or by both means according
to the necessities of the case. I propose moreover to combine with such coin-
controlled mechanism receipt delivery mechanism acting so that when a coin
has been deposited a receipt will be given showing the value of the coin and the
specific signal set thus serving as a check upon the making of false claims as
to mal-operation of the machine. I also combine with the use of such coin con-
trolled mechanism means for printing or autographing the said receipt together
with adjunctive information according to the needs of the case and this informa-
tion may if desired be recorded in duplicate or triplicate one part thereof being
given to the person operating and another being retained as a record within
the machine for the use of the inspectors. I moreover arrange these elements so
that instead of one coin a series of coins or of bank notes may be combined to
produce the desired effect alone or with other articles deposited by the operator
and in which means are provided for identifying each specific operation or receipt
with the total of coins or articles deposited at the time of setting the respective
signals.
I moreover combine with the transmitter as described telephone apparatus and
auxiliary signal devices such as push buttons or equivalents operating either
separately or as a necessary effect of some prescribed manipulation to indicate
at the receiving station whether the transmitter has been used or the telephone
is to be used.
Receiving apparatus. This includes an annunciator which may be made in
various forms but which I prefer to make, generally, in the form shown in my
British Patent Application 1301 of 1898 in which:--
5
A watertight tank having a base of insulated material as a back and an opposite
face of glass as a front, is filled with an electrolyte adapted when decomposed
by an electric current passed through the tank by way of two electrode terminals
to locate at one of these, as a positive pole, a product of this decomposition and
thereby to change the appearance of this pole. Upon this base I mount a number 5
of platinum plates or buttons, for use as such positive poles, of several circuits,
simultaneously, and suitably connect these by wires passing through the base

page_text: to the separate external circuits, cach connected to one contact of a distant push-
button, and the other contact of each such button is connected by a return wire
with one or more other plates which form the negative electrode co-operating
in the tank with the first named plates as positive electrodes or terminals for the
purposes of the decomposition referred to. The action described will thus serve
to change the appearance of the positive disc which corresponds to an operated
push button, and in this way the device forms an exceedingly simple and compact
annunciator.
I have theretofore used, as the electrolyte, an aqueous solution of haloid salts,
preferably of potassium iodide, and I have increased the viscosity of the solution
by the addition of glycerine, whereby the bubbles of gas, formed as a secondary
electrolysis of the water during the decomposition of the iodide, will not dislodge
the decomposed iodine from the positive plate as rapidly as it would without
such addition.
I have also added to the solution sodium hyposulphite, the products · ¦ which
will combine with the products of the electrolysis of the substances already
named in such manner as to retard the gradual staining of the solution normally
resulting from intricate chemical and electro-chemical re-actions, this retardation
being effected by a process of "bleaching" the iodine. Moreover, in order to
hasten the disappearance of the indication given by the electrodes I have arranged
to blow air into the tank at will, by means of an air bulb, so as to circulate the
liquid and thus wash away the deposit immediately, so that after an indication
has been noted, may be removed so as to avoid confusion in noting subsequent
calls.
The tank is preferably arranged so that the insulated back plate and the glass
front are held together by clamps, separated by a wall formed of a soft rubber
gasket compressed between these two plates. The air bulb is arranged to blow
air through a rubber tube which is immersed in the solution to form the surface
passes to the bottom, and is then bent at right angles so as to run along the
bottom, and has holes pierced at suitable intervals at the top of this bottom exten-
sion so that the air forced through it will rise in bubbles and agitate the liquid
at several points simultaneously. At the top of the tank is a hole through which
a suction tube may be introduced so as to empty the tank by suction from a
suitable syringe or pump when the tank requires cleansing or the withdrawal of
an exhausted solution and this suction may be started, and a suitable vent hole
or loose fitting of the gasket at the top of the tank, will admit air so that syphon-
ing according to the well known laboratory method will take place until the
tank is emptied. I have made the following improvements upon the organis-
ation described-I have discovered that many causes produce a tarnish, oxide
or other deposit on the positive plates much more quickly when the solution
described is used than when use is made of sugar as a thickoning medium and I
believe that the sugar also acts chemically upon the tarnish so as to keep the
points bright. It is also possible to increase the density to any practical degree
required which has a very important bearing upon the operation of the system
in certain contingencies and organizations. I have discovered that when sugar
is used for this purpose it must be boiled to a degree sufficient to prevent its
recrystallization and I have also discovered that some forms of commercial
glucose produce very good results. I have also improved the solution by the
substitution of sodic sulphite for the hypo-sulphite as a too free use of the bleach-
ing salt will not produce a precipitate and the resulting turbidity will not appear
SO 80011. The tank is moreover preferably made so that the air duct is arranged
below the level of the plane of the terminals and in large tanks this may be
advantageously done by cutting an open channel in the supporting rubber block
and locating this so that the soft rubber gasket will serve as the fourth wall
when the glass is clamped on. I have also arranged to cast or mould vitrious
strips with bosses for the terminal plates and so shaped that they can be built
into the proper aggregation and I have arranged locking devices and glass tubes

page_text: containing the suitable indications and adapted to be held in place by the locking
devices in proper proximity to their respective terminals. I have also discovered
that there are preferable forms of proportioning the distances between the sup-
porting background, the terminals, the number strips and the inner side of the
front glass as these proportions for a given solution will vary or effect both the
degree of deposit and its duration.
I have also improved the devices for taking out the solution as well as for
agitating it.
In addition to the annunciator there is a switch board having a separate ter-
minal switch for every line wire and sub-station and I propose to arrange this
switch board so that it will be directly proportional in size and similar in arrange-
ment to the annunciator with its various terminals thus making it possible for
an experienced operator to locate in the easiest possible manner a switch which
is in connection with an annunciator terminal that has operated. These switches
I prefer to make of a pin and spring the spring being preferably bent into a V
at the end and this V being slotted so that instead of having one point of contact
produced by the edge of the V where it runs tangent to the circle of the pin
there will be several points of contact without in any degree impairing the rigidity
of the spring. I prefer to run the pins through the supporting back board
and to attach one wire to a nut or suitable device at the inner end of the pin
and to make suitable wire connections to the lower end of the spring and then
to connect one of these elements to its corresponding terminal in the annunciator
anl I propose to embed all of these terminals and cross connecting wires in a
solid bed of some suitable fusible mixture or cement as rosin and wax for example
thus protecting all parts from damage. I also prefer to arrange my annunciator
at the side of the switch board so that no danger from leaks of any sort may arise.
In addition to the parts described the central office apparatus will include a
suitable indicator of any desired character and I have devised an exceedingly
trustworthy form of step by step indicator which co-operates with suitable man-
ually operated devices so that when a suitable handle is moved to one position
and proper connections are made with an operated transmitter the indicator
movement will work in correspondence with the indication on the transmitter,
and remain at its last step until the controlling member is again moved where-
upon the pointer will be unlocked either electrically or mechanically. In the
form devised the motion of a part which permits of the operation of the step by
step movement will moreover control the motions of the circuit changer which
co-operates in such manner with a connecting plug which is common to all the
circuits of the system that the necessary electrical manipulation will coincide
with the necessary mechanical movements which free the receiver. The electrical
parts I prefer to arrange within a case which contains the movement proper of
the indicator and I propose to form terminals upon this inclosing case so that
these may co-operate with the various posts or supports so that when an indicator
box is shoved into place it will be automatically brought into position to cause
the necessary function to be produced whenever the mechanism is properly mani
pulated. I propose particularly to cause the depression of an arm to act in-
directly upon extensions which operate to permit suitable impelling pawls to
move so that the wheel is free to be rotated by the magnetic armature. Suitable
restoring adjustment will also be provided; the moving of this lever changes a
circuit so that a connecting plug which is adapted in turn to be used with every
of the switches and hence of the stations may be retained in operative connection
with the switch with which it was last used while the circuit external to the
plug but connected with the receiving mechanism acts merely as an extension
or loop until the operation of the controlling member described causes this loop
to be broken so that the end towards the annunciator is cut out while the other
end secures the co-operation between the transmitter at the sub-station and the
indicator. I moreover arrange this contact changer so that the change is pro-
duced directly as a result of the tendency of the lever or spring and the action

page_text: of the controlling device mentioned is preferably only permissive in that it
makes possible for the tendency described to manifest itself.
I prefer to mount the indicator dial in such fashion that it may be detached
from the motor mechanism proper by very simple action which requires no dis-
adjustment of the working parts of the indicator and I prefer to divide the
necessary functions or indications of the dial so that one function is performed
by the aid of indications on a surface which is more closely connected with the
dial mechanism than is the other. To understand the general nature of this
portion of the improvement, it is to be remembered that every signal received
consists of two groups of impulses one of which is produced and varied by the
number of the column containing the chosen word and the second is varied by
the distance over which the pointer has been moved from the outer edge of the
dial. Consideration will show that no ordinary device will suffice to combine
these two sets of groups or impulses and I have succeeded in producing a most
simple device which fully serves this purpose and to make use of it the system
requires that the receiver should bear consecutive numbers corresponding to the
columns of the transmitter and that these numbers shall be arranged in a circle
around the indicator pointer at distances corresponding to the steps of the wheel
and these numbers I prefer to mark upon a circle which I attach to the indicator
box proper. Within this circle I arrange a dial which is practically a duplicate
of the transmitter dial but which has also inscribed upon it index numbers which
serve to localise the desired indications. The plug consists of two concentric
tubes insulated from each other and suitable attachment pieces at the inner end
serve as screw posts to enable double cords to be connected therewith. The
operation of the indicator lever may also be made to control a counting device
thus serving as a check upon the use of the system.
This counter will ordinarily be arranged to advance one step for every oper-
ation of the dial and hence of the indicator operating lever but for special
purposes such as a system designed to record the value of order or signals sent
from the transmitters as for instance would be the case if restaurant orders were
given by means of this machine I arrange the counter so that different classes
of indications will control varying numbers of advance steps in the counter
which may or need not be multiples of the lowest unit.
The transmitter already described I arrange so that normally the movement
when detached from the wall plate or box is protected by a suitable casing
which may be entirely open at its outer end or which for protection of the work-
ing parts may be covered in such manner that only the co-operating terminals
protrude. Whichever form is used will in many instances admit of the joint
use of an auxiliary part designed to afford ready access to the parts requiring
most frequent inspection and adjustment and which in the preferred form in
view would be the cam and hook.
Dated this 24th day of March 1898
F. (FELIX) BENEDICT HERZOG.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Electric Signalling, and Adjuncts
thereto.
I, FELIX BENEDICT HERZOG, Ph.D., of 1123, Broadway, 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 particularly described and ascertained
in and by the following statement:-
The object of this invention is to improve various parts of a system of automatic
signalling or communication.

page_text: The various parts included in this system I design for use either separately
or in connection with less than the entire number of other elements or in a
system in which all are used simultaneously; the degree of combination depend-
ing upon the commercial result required in each instance. As a whole the system
comprises signalling instruments called transmitters at each of several stations
which with respect to one or more common stations are called sub-stations and
at the common station or stations suitable indicating and receiving mechanisms
controllable either from a sub-station alone or from this station jointly in co-opera-
tion with apparatus located at other sub-stations or at the central station or at
auxiliary stations.
"
The system as a whole is described as comprising for the transmitters only a
special form, which I call a sliding arm, double signal latent transmitter as one
of its main characteristics is that the signal is not transmitted immediately after
the operation, but remains
set" or
latent" until it is released or caused to
operate as the result of some act independent of that performed at the trans-
mitting station. I do not herein claim such an apparatus broadly, and as to the
specific improvements shown as embodied therein, I do not limit myself to their
use in transmitters embodying such a latent feature.
In the accompanying drawings in which like numbers represent similar parts,
Fig. 1 is a general view of the transmitter, a part of the front being broken away
and the wall-box being shown as imbedded in a section of a wall partition;
Fig. 2 shows a detail of the sleeve forming part of the transmitter; Fig. 3 shows
a rear view of the contact springs and push button device forming another part
of the transmitter; Fig. 4 shows the main portion of the signal transmitting
mechanism; Figs. 5 and 6 details of the controlling magnet and its armature;
Figs. 7, 8 and 9 details of the transmitter; Fig. 10 a general view of the appa-
ratus at the receiving station; Fig. 11 a perspective of the indicating portion
thereof; Fig. 12 details of the annunciator and switchboard shown in general
view in Fig. 10, while Fig. 13 is a general diagram of the circuit and system.
The transmitter shown combines many points adapted for use with trans-
mitters which in some respects vary widely from the one herein selected as a
typical embodiment, but some of the features are applicable only to this special
form. It is an improvement upon the apparatus which I have heretofore made
and which I do not claim herein broadly, but the general nature of the transmitter
is that a dial bears suitable indications arranged in two intersecting directions,
and a controlling device is adjusted so that any person desiring to signal may
move a co-operating pointer to specify any one of the indications on the dial,
and thereby will move suitable circuit controlling devices so that the correspond-
ing signal will be controlled over the line leading to a second station. A series
of such lines leading to the same station form a system specially applicable to
hotels, telephone exchanges, police signals etc., although it is to be understood
that one transmitter used independently of any others is equally within my
invention.
Where a number are used together I combine such transmitting elements as
described with independent elements whose function is to retard delivery of the
signal until some action is performed at the receiving station, or at some other
point along the line, and such retarding mechanism may be made in different
forms and as herein shown comprises a motor controlling clock work restrained
by a detent, in turn released by the action of an electro magnet upon its arma-
ture when the magnet is energized as a result of action independent of that
performed by the operator who sets the signal. I shall first describe the
transmitter.
Transmitter:-In Fig. 1, a suitable circular frame, 361, has a dial upon which
radial and concentric lines intersect so as to form separate spaces in which indica-
tions H, H, I, and I, etc. are inscribed. At the centre of this dial a suitable
hole permits the stem of a T shaped sleeve, 490, to project so that an arm, 498,
may be engaged by it and rotated around the dial so that the downward project-

page_text: ing pin, 500, fastened at one end of the arm may be set over any indicated mark
on the dial (the said arm can be rotated around the centre, and is also free to
slide in and out of the sleeve). Fastened to the dial plate by suitable devices
as screws, 523, and collar, 485, is a rib 521, which has a series of zig-zag steps
so arranged that they will engage with the end of the pin 500. One such step
will be provided for each circle of words on the dial, and these steps will each
correspond in height to the spaces on the dial, the general arrangement being
such that the words on the dial may be considered either as a series of concentric
circles or a series of radial spaces. If, therefore, the pointer has been set say
at the point marked H₁, a further rotation of the pointer without changing its
position within the sleeve would cause the pointer to be stopped at the outermost
step of the rib, whereas if the pointer had been set say at space I, it would in
turn be stopped by a step in a space corresponding to the 3rd space from the
outside, and the arrangement of the rib is furthermore such that this 3rd step
would also be as many units of distance to the right of the first step as the circle
containing I was distant from the circle containing the H₁. The sleeve
described is shown more clearly in Fig. 2. In this figure 497 represents the
longitudinal hole in the sleeve, 498 is a sliding arm, 492 is a vertical hole in
the sleeve; 462 shows the main arbor of the clock work mechanism to be described
hereafter; 461 is a shoulder adapted to fasten this in place within the collar 489;
the outer edge 485 of the collar serving as a support for the inner end 393 of
the rib piece, which is furthermore prevented from shifting sidewise by the
extension 487; the said collar being held in place by a suitable flange 486 which
fastens the entire piece to the frame plate or dial support 434. The sleeve
piece 490 supports a hollow plunger 496 pressed into the grooves, 505, 499, cut
on the lower side of the sliding arm by a suitable spiral spring, 495, which
abuts against the head of the screw 494. This screw head holds an inner
rim 462 of the sleeve shank, 491, in place, this inner rim being preferably
arranged so as to have one side at least straight so as to enable it to grip the
arbor and rotate it when the sleeve itself is rotated by means of the arm when
the latter is set at any indication on the dial, and it is still better to cut the
upper end of the arbor square. The object of the plunger is to keep the pointer
in the position to which it has been set with respect to the sleeve.
The parts just described are assembled by first pushing the sleeve upon the
square end of the arbor then inserting the screw into a suitable tapped hole
within the arbor thus preventing withdrawal of the sleeve, then inserting the
small spiral spring and cap, and then sliding the arm into place. At one end
of this arm is the pin 500 projecting downward far enough to designate the
corresponding indication chosen on the dial and ending on the upper side in the
knob 501 adapted to be easily grasped, and the rear end of the arm has fastened
to it a tag 502 with a projection 503 which enables the screw 504 to be screwed
into the arm along its axis so that the tag will be raised far enough above the
arm to enable this tag to project over the sleeve when the knob end of the arm
is pulled out all the way, thus saving space and also acting as a step to prevent
the arm from being pulled out of the sleeve by accident. The pointer just
described will enable the operator to rotate the main arbor during the act of
indicating on the dial.
Fig. 7 shows the square end of the arbor on which the sleeve just described
fits and the hole for the fastening screw. Permanently attached to this arbor
is a lock-plate, 477, a portion being shown broken away. This lock-plate is
attached to the arbor by means of a bushing 484, suitably riveted or forced upon
the arbor in any manner. This lock-plate is also shown in Fig. 4. The lock-
plate rivet, 476, holds a pawl, 473, so that when the pointer is moved in a clock
wise direction it will carry with it the lock-plate and the pawl, and the tooth of
this will engage with the ratchet wheel, 471, so that this will be carried with
it. This ratchet wheel is broad enough so that both the pawl, 473, just described,
and a second pawl, 472, will be able to work independently when they pass one

page_text: another, the second pawl being fixed to a gear wheel, 470, by means of rivet, 474,
and being held in place against the teeth of the ratchet by spring, 478, fixed to
the said gear wheel by rivets 480 and 482 passing through the holes 480' and
4821 in the gear wheel, and in similar manner pawl 473 is held against the ratchet
by a spring 479 held in place by rivets 481 and 483 passing through holes 481'
and 483 in the said lock-plate. The rear end of the ratchet wheel terminates
in a bushing not shown and provided with a pin in the usual manner, to carry
the inuer end of the main spring 466 of Fig. 9, the outer end of this spring
being formed into a loop 4661 which engages with a suitable projection 465 by
which it is anchored; the general arrangements of the parts, therefore, being
such that when the arbor is rotated in a clock wise direction by the hand it will
carry the lock-plate whose click will rotate the ratchet which will carry with it
the inner end of the main spring and wind this up, because the outer end is
held firmly by the attachment described. The gear wheel 470 will not be moved
during this motion because this is supported loosely on the shaft and there is
geared to it the pinion 509 of Fig. 4, and on the arbor 510 is fastened a second
wheel 508 gearing with a pinion 444, and a third arbor 439 which carries the
escape wheel 444 co-operating with a fourth arbor 446 by means of the escape-
ment verge 445 the pallets of which 445' and 445" are arranged so as to be
vibrated as in ordinary escapements. The said arbor 439 also carries a cam 436
the function of which will be explained in detail later. The arbors 510, 439
and 446 terminate in suitable pivots 511, 438 and 447 respectively, all of which
are mounted between the support plates 434 and 433 respectively. The main
gear wheel 470 has riveted to it the spring box 468 within which is contained
the main-spring already described. As soon as the tension of the winding act
is removed, the mainspring would tend to uncoil, but normally cannot do so
because of the permanent connection of its inner end with the ratchet, the teeth
of which engage the second pawl 472 which in turn is fastened to the gear wheel
and this cannot move because the train is locked by the point 427 of the
armature 426, normally held away from the magnet by its weight aided by the
flat spring 425. But, as soon as the magnet is energized, as described hereafter,
it attracts its armature thus raising the point 427 to the position shown in
Fig. 8 so that the point 427 and the tooth 440 will no longer hold the cam, and
thereupon the clock work runs down. In order to lessen the wear on the engag-
ing edge of the cam tooth, a piece of hardened steel 441 is preferably inserted at
this point and the cam as a whole is made adjustable and detachable to its arbor
by means of the screws 442 and 443.
In order to enable the operator after he has moved the pointer beyond the place
at which he wishes to rest it to turn it back I have arranged the following:- -With-
out further provision it would follow that if the pointer be rotated backwards and
forwards several times the main spring would be wound up by each clock wise
rotation and the contra-clockwise reversals of the pointer would fail to unwind the
spring and would merely cause the lock wheel 477 to carry along the pawl 4733 and
after a few such reversals the main spring would be wound up so tightly that
further operation would be impossible, and probably some portion of the mechanism
would break if sufficient force were applied to the pointer, or the spring itself
might be wound so tightly that the friction of the parts upon each other would
prevent its unwinding. In order to obviate this and to make the apparatus so
that it may work continuously as described, I arrange the anchorage point 465 so
that instead of being rigidly fastened to any part of the mechanism, such as the
frame plate 433, it forms part of a friction washer 464 which is fitted against the
said plate 433 and clamped in place by bushing 463, suitable upsetting points 46311
holding it in place, and the friction is preferably arranged so that the inner edge
of the friction plate will bear against the outer edge 463 of the bushing described;
this bushing having a flange as shown in dotted line which holds the friction plate
in its position against the plate 433. In other words the friction plate is clamped
between the flange of the bushing and a collar on this bushing is firmly riveted

page_text: to the outer plate, and the outer edge of the bushing and the inner edge of the
ring form the main bearing surface although the friction of the plates is also used.
The friction ring is slotted as shown, so as to give greater contracting force to it.
The tension is so arranged that an abnormal tightness of the spring will cause the
friction plate to be carried along at subsequent rotations until the tension is again
lessened by the normal unwinding of the clock work consequent upon a release
of the apparatus.
The parts here described form the motor device, and its function is to control the
delivery of signals, which, in the form of transmitter herein shown, are caused by
a number of equally timed interruptions of the circuit together with a larger inter-
ruption or closure, form a differentiation in the regular sequence of such inter-
ruptions, and the number of interruptions which proceed and follow the space will
determine the particular signal chosen.
The rear of the arbor, or the front of the arbor looking at the machine as shown
in Fig. 4, ends in a narrowed part 459 upon which is mounted a hub rigidly
fastened to the break wheel 112. This mounting is by means of a set screw 455,
together with a second similar screw, and these two screws enable the break wheel
to be adjusted and clamped tightly to the bushing and also to enable the break
wheel to be readily taken off without disarrangement of any other part of the
mechanism. This break wheel is of metal and has a number of teeth 451 of equal
size and one tooth 451° of space much larger than the others. These teeth are pro-
portioned to the total periphery of the circle so that they are similar to the columns
of the dial, there being one such tooth for each column; and, on the dial, preceding
the first column is a blank space which is so long that when the arm, which by
reason of its guidance by the sleeve fixed to the arbor, as already described, moves
with the arbor, the arc traversed by the pin between an indication in the first
column and the point where the pin at the end of the arm is stopped by the first
step of the rib will be equivalent to the amount of rotation of the break wheel from
the beginning of the big tooth to the middle of the next succeeding tooth. The
adjustment of this big tooth with reference to the permanent position of the break
wheel on the hub and the other parts mentioned is such that the V shaped point
on the break spring 111 will rest on the first tooth at the left of the break wheel
as seen in Fig. 4 when the pointer is engaged by the first step, and as the radial
positions of the various steps are proportionate to the division of the circle, it follows
that as many succeeding teeth as there are steps will normally rest against the
brush at the respective positions of the pointer when this is limited by the
various steps on the rib. As shown the pointer would be stopped at the second
step. Thus if the pointer were rotated to the fifth column, and then were pulled
inward to indicate the second word from the top of that column the normal position
of the break wheel would be such that the fifth tooth to the right would rest against
the brush, that is, the tooth opposite 458, and as the break wheel would revolve in
the reverse direction under stress of the running down of the clock work the break
wheel would continue to rotate until it came to rest at the second tooth as shown,
when the pointer pin came into engagement with the second step of the rib; a
similar operation would consequently produce a characteristic series of two sequences
for every position of the pointer on the dial.
I have heretofore found it difficult to arrange the break spring so that while
pressing upon the wheel with sufficient force to insure good contact, it would not
dip into the spaces separating the teeth so as to continue the closure longer
than necessary, and I have not found it satisfactory to put insulating material
between the teeth as has been done heretofore, both by reason of expense and
because it is desirable to have the sharp edges of the teeth scraped by the brush
so as to clear off any corrosion or dirt, and I have succeeded in solving this diffi-
culty by fastening an insulated plate 452 at the rear of the break wheel by means
of the rivet 453 and by permitting this disc or plate to project to a very slight
degree, the resiliency of the break spring being sufficient to overcome this minute
projection so that the spring could make good contact with the wheel.

page_text: In order to make it impossible to disarrange the break spring by reason of care
·less inspection or fingering, I have also limited its motion in the reverse direction
by a suitable abutment herein shown as one edge of the block 412, whereby i
cannot be bent beyond its limit of resiliency and which block also serves to hold
in place the break spring by the screws 410 and 411 and to connect the winding 409
of the magnet 110 to the spring by the latter screw; the block serves also to hold
the other magnet winding 407 in contact with the return wire 400 by means of the
'screws 406 and 404 which both connect with the bridging piece 405. The magnet
itself is held in proper relation to the frame work (preferably made a portion of
the frame 434) by means of a cast backyoke 408 to which it is attached by means of
suitable screws 418, the yoke being attached to its plate by screws 423 passing
through the projection 422 and kept from rotating by the steady pin 424 inserted
in place after the magnet has been rocked so as to come into the proper position
with respect to the armature in case of small variations of proportion to adjust-
ment of the parts. This back yoke has a tongue 413 arranged to support the insu-
lating block described, the latter being provided with a flange recess 417 in which
is cut a suitable slot 416 so that after screw 414 has been fitted into hole 414', the
blook can be rotated around this screw as a centre so as to keep the exact tension
and adjustment at the point of the brush, and when this has been secured screw 415
can be tightened in its hole 415¹ so as to preserve this adjustment. I have also
arranged to preserve a good insulation between the iron back yoke and the magnet-
spool connecting wires 421 of Fig. 5, by inserting an insulated sheet 420 and
shaping this so that there is room for the magnet core 419 to project slightly at
the rear end of the magnet, according to the best approved practice in the manu-
facture of magnets for, similar purposes. In Fig. 6 is shown a reverse view of
the armature, together with spring 425 which serves to prevent actual contact
between the armature and the cores of the magnet, and also as a retracting spring.
The pivots 428 of the armature are arranged to play in the front and rear plates of
the movement, the front plate being provided with an attachment 431 fastened to
the said plate by screw 432 so that the armature may be taken out for adjustment
without necessitating the dis-assembling of the entire movement, this being
retained during this operation by studs 448 and 449 and one or more additional
studs or similar devices. I moreover attach the wire 400 to the plate so as to
prevent accidental dis-adjustment of the former, by means of clamp sleeve 402,
held down by a screw 403 against the plate 433, and I put the insulated cover-
ing 401 about the said wire for better protection. The armature also carries at
its rear end the bell-hammer 430 supported by a bent rod 429 attached to the
armature 426 by the rivet 507 for engagement with the bell 514 shown in Fig. 1;
this bell being preferably attached to the front space by means of the anchor
piece 515 to which it is fastened by screw 515 and steady pin 5151, the bell-
hammer rod being bent so that the head 430 will be within the bell, striking it
on the inside.
In order not to have this bell struck at every impulse produced by the break
wheel, which would ordinarily happen because the magnet is arranged in series
with the teeth on the break wheel, I have arranged a cam 436 as follows. The
ratio of the gearing described is such that for every advance of one tooth in the
break wheel the cam will make one complete revolution, and the periphery of the
cam is so divided that the space 440 will normally be under the point 427 of the
armature only at the resting point of the arm. The co-operation of these points
with the others already described is as follows:-While a tooth touches the brush
during rotation the magnet will be energized and will hold up its armature, and
this is the point at which the hollow of the cam would permit the armature to fall
low enough to block the movement, but for this attraction. The higher point of
the cam will ride under the point of the armature during the interruptions of the
circuit, and therefore the armature cannot block the operation by falling into the
blocking position at the moment when the current would be broken and the magnet
therefore would be cut from electrical control. Inasmuch as the normal position

page_text: of rest when the pointer reaches the rib is such that a tooth is always then under
the break spring, it follows that during this position of rest the apparatus remains
on closed circuit, and hence the magnet is subject to control; the adjustment of
the armature motion is so proportioned to the striking position of the bell-hammer
that the latter can only ring when the armature is given its full play, that is,
during the normal position of rest. In this manner the bell can be operated from
a distant station at will during the position of rest, but will not cause a disagreeable
ringing during the normal rotation of the mechanism. 435 is a piece bent out
from the plate 433 so as to serve as an auxiliary or safety rest for the armature.
In order to make it certain that the pointer will always be left pointing directly
in the middle of a column and that the brush may always be on a tooth during the
position of rest, even when the weight of the arm extended at full length and
in a position which is horizontal when the apparatus is duly mounted upon a wall
night tend to shift the adjustments, I have arranged the counter-spring 456;
the inner end of this is fastened to a pin 458 on the break wheel hub and the outer
end is formed into a loop 456" secured by a rivet 4561 and fastened against pro-
jection 457 of the frame plate 433. This spring need be only strong enough to
serve the purpose referred to. The apparatus just described is housed in a suitable
box 370 at one side of which screw 375 passing through the tongue 377 fastens
the cast auxiliary box 376 so that the latter may be swung for ready inspection
of the cam and armature, which project through a suitable hole 378; the said
auxiliary box being fastened in place by a screw 399 which clamps down the
tongue 398. Contained within the main box and mounted upon the front plate are
the push button and contacts shown in Fig. 3, and in fractional sections in Fig. 1.
A suitable push button 534 enclosed in a bushing 530, is attached to shank 380,
the latter being attached to the metal strip 381 which is attached to the wooden
block 379, by screws 383 and 384, and which is also attached to contact, exten-
sion 114. Similar contact extensions 117 and 389 are attached to the block by
screws 395, 394 and 387 388 respectively, and the latter extension is electrically
joined with the spring 386 and 115. In addition to these parts the contact plate 113
is attached to the block by screws 391 and 392, the latter serving also to connect
the wire 400 with the magnet as shown in Fig. 4. The spring 117 is connected
to the frame plate 434 by a screw 382 and wire 396, the latter passing through a
hole 397 in the block 379. The co-operation of all the parts is such that in the
normal position of rest the push-button metal spring 381 is held in contact with
plate 113, but when this button is pushed this contact is broken and the said metal
spring 381 is electrically connected during the act of pushing with the contact
spring 115 and the spring 117 is in constant electrical connection with the magnet
and break wheel because the latter is not insulated from the frame work which
includes the frame 434. Surrounding the push button is the bushing 528 fastened
into the dial plate by a suitable flange 380 and acting to guide the button from
being jammed sidewise, and a similar collar or bushing 520 forming an additional
support and protection for the inner end of the rib and the bushing which sur-
rounds the hub of the sleeve.
The essential portion of the transmitter has now been described, and before
proceeding with the description of the operation of the entire system, I shall
explain how I have arranged to mount the boxes upon the walls where they will
ordinarily be located.
For this purpose I arrange a wall fixture of any suitable character and prefer-
ably comprising an outer piece or wall box 311 and an inner piece or base plate 261.
The wall box is provided with flanges 273, 272 and 280 adapted to be held in place
by surface plastering of the wall in which the box is sunk, a section thereof with
plaster removed being shown in the drawing; and with three insulating blocks
of which two, U and U₁ are shown, these being preferably attached by slots 299
engaging the flange projections 300 on the wall box, and being furthermore con-
neeted by means of nails 303 passed through these two portions. Suitable outlet
holes 304 for wires are also provided although the wires may if desired be brought

page_text: in through the open back. This wall box is designed to be locked in place by
screws or tie-wires passed through the holes V cut in one or more wings Wat
the bottom of the box and suitably anchored at the back. The upper block U
has a notch Q, and the lower edge of the wall box has a notch R as guides for
arranging the box perpendicularly as nearly as conveniently possible, but absolute
dependence is not placed upon the proper placing of the wall box, as, in practice,
it is found that the cheap class of labor which would probably be employed for
this work under ordinary conditions could not be relied upon to center the boxes
properly, and if improperly centered a great deal of extra work and marring of the
plaster would be required before the box could be straightened. This box is
deep enough to have inserted within it a base plate which consists essentially of
a frame work adapted to support the contact block to be described hereafter, and
three supporting legs of which two, 306 and 307 are shown. The relative pro-
portions of these parts are so arranged that the base plate after it has been inserted,
may be rocked from side to side, or brought in and out entirely or at top or
bottom, then suitably wedged in the proper position and then fastened by means
of screws through holes 287, 288 and 290, 291, 292 etc. The lower end of the
base plate terminates in a lug with an upward extension 282 in each side and a
screw hole 302ª at the bottom and bearing on its lower edge a small insulating
block T designed to prevent accidental contact between this portion of the base
plate and the wall box. The flanges are designed to prevent sidewise motion of
the tongue 364 which forms a part of the enclosing case 366 of the transmitter,
and the hole described coincides in position with a similar hole 302 arranged in
the said tongue so that a screw may be placed in the latter and into the former
hole which is tapped to enable the screw to be fastened. This screw may also be
passed through hole 363 of the ornamental frame 361. At the upper end of the
base plate, there is, on each side, a short projection or flange 263 and 262 designed
to receive and hold in place the case attached to the transmitter, and on the very
top edge is a short pin 372 over which a hole in the upper end of the transmitter
case may be fitted. The parts just described make it possible to
insure the level attachment of the transmitter within wide margins
of error, and also to attach a transmitter by the simple operation of fitting it in
place, lifting it up about one eighth of an inch until the pin and hole engage
and then permanently fastening the transmitter in its proper position within the
receptacle by means of the one screw which is threaded into the hole 302. The
notch R, R, in the bottom of the base plate is also used as a guide notch co-operat-
ing with a similar notch on the leg 306, to facilitate the operation of setting these
parts.
The attachment of the transmitter is designed to do more than described because
the same act will also bring the three contact springs on the block 379 of Fig. 3,
in their proper positions to rest upon three nuts and screws of which two, A and I
are shown mounted upon the insulated block 145 of Fig. 1, which is fastened to
the base plate by screws 267. These nuts form the terminals of the respective
lines, and, therefore, inasmuch as all parts are made of uniform size, any wall
base plate may be supplied with a transmitter by this simple operation, and the
transmitters may be readily removed for inspection and replaced without danger
of error in replacing disconnected line terminals.
At the receiving station is located the apparatus shown in Fig. 10 and compris-
ing in the embodiment herein shown, an annunciator portion with a separate
indicating device corresponding to each outgoing line and distant transmitter; a
switchboard portion with a similar number of units; and an indicating and con-
trolling portion which is designed to be used in turn with each one of these lines-
the whole encased in the one supporting frame or box 206, 82, 205. The annunciator
here described consists essentially of a cell with a glass front and containing an
electrolyte and a series of electrodes 96 and 97 etc., each one of which is connected
to a separate line as hereafter described. Mounted upon a base of suitable insulat-
ing material, as rubber, 229, are a series of rubber screws 242 adapted to clamp

page_text: under their heads a series of glass tubes 243 bearing suitable numbers, preferably
inclosed therein and marked so as to correspond with the electrodes, and thus to
identify the respective lines. At some other portion of the tank, as at the sides
thereof, are other electrodes, 98 etc. called negative discs and attached to the return
connection of the source of current. Back of the electrodes is a plate of white
glass 240, held by means of screws 242, and serving in connection with other
strips of the same material as a white background, a space being left between
the strips so that the leading-in wires 149; of Fig. 12, may be enabled to reach
their respective electrodes. The rubber back-plate 229, is channeled out along one
side and the bottom at a short distance from the edge, this channel 230, serving
as an air duct which, when closed by a soft rubber compressed gasket, 232, will
permit air to be forced from the blower bulb 222, through the duct and by means
of the orifice 231, drilled diagonally through the rubber into the solution or
electrolyte whence it will rise in bubbles which will rise in the narrow space left
between the front glass 233 and the rubber backing, and these bubbles will agitate
the liquid and will hasten the diffusion and disappearance of the electrolytic stain
which is caused by decomposition of the proper electrolyte, one of the products of
the electrolysis being deposited upon the positive electrode which thus acts as the
annunciating device for the transmitter line with which it is connected. The bulb
is pressed after the operator has noted the call, and the apparatus is thus restored
ready for subsequent repetitions of the operation, but a characteristic of the device
is that the deposit which serves to mark a call, will fade of itself, its duration
depending upon the viscosity or density of the liquid and the original intensity
of the stain, which, in turn, depends upon the strength of the solution, the duration
of the closure at the distant station and the strength of current.
Fig. 12 shows a mechanical construction of these parts, the clamp 235 serving
to support the set screw 237 which bears against the gasket frame 234, so as to
save unnecessary risk of breakage during the act of screwing, the said clamp being
held in place permanently by screw 238, at the back, which may be screwed into
the rubber or, as shown, into a wooden back frame. The soft rubber gasket 232,
serves not only as the fourth wall, which with the channel cut into the rubber base
acts as the air duct for the blower described, but it also acts as a water tight pack-
ing to keep in the electrolyte from leaking out of the cell. The blower described,
comprises also a valve box 221, of any suitable construction so as to admit air with-
out, and a length of tube 220 the end of which, 218, is adapted to be fitted onto a
nipple 219, brought into the upper edge of the rubber back 229 in proper position
to communicate with the channel duct described. A suitable bracket 215, with
a clamp 214, is adapted to receive and hold the tube, and a suitably ornamental
frame 209, is preferably arranged to hide the clamps from view. A preferred con-
struction for the devices thus generally described will include a hard rubber
cushion 247, over which a piece of thin platinum foil 97 is placed and a platinum.
wire 149 bent at the outer end will pass through the holes in this foil and cushion,"
thence between two adjacent slats 241, thence through a fine hole in a soft rubber
plug 248, and thence to anchorage upon a plate 245, to which it is attached by
screw 250, and from which by way of screw 249, an ordinary copper wire leads to
a corresponding section of unit of the switchboard. All of such disc wires
described are preferably imbedded in a layer of cement, 246, as a wax and rosin
mixture, for instance, which serves both to prevent possible leakage in case of any
defects in the plug packing and also to prevent mechanical accidents to the parts
embedded therein. A suitable electrolyte is disclosed in my Patent Application
1301 of 1898, and I do not broadly claim this invention herein. The electrolyte
there mentioned consists, for example, of potassium iodide which is decomposed
so as to locate the brown iodine upon the positive electrode, and this serves to
point out the corresponding line to the receiving operator, and in order to hasten
the dissipation of the deposited iodine, the solution includes sodium-hyposulphite,
and in order to make the solution more viscous so as to prevent a too rapid rise of

page_text: the bubbles of gas during electrolysis, the said application provides for the addition
of glycerine. I have improved this solution by the substitution of commercially
pure sugar dissolved in water, and have substituted sodium-sulphite for the sodium-
hyposulphite. The sugar is ordinarily better than the glycerine because it reacts
upon a tarnish or stain after deposit upon the electrodes as a result of the elec-
trolysis of metallic or other impurities which have found their way into the
solution, and this keeps the discs very much brighter than when glycerine is used,
and the sulphite I have found to be as effective as the hyposulphite, and it does not
tend to produce an objectionable cloudiness in the solution as in the case with the
hyposulphite.
The wire which has been described as leading from each individual disc, leads
to its corresponding switchboard unit in the following manner, first to a suitable
bolt fitted with a nut 346, and arranged to hold in place the spring 130, of a spring
jack combination, this spring being held against post 129, which in turn passes
through a hole in the insulated support 252, which also bears the spring, and is
then clamped in place by means of a bolt 146 which also holds in place a suitable
washer pressed upon a rubber bushing 251, and connecting with the outgoing
wire 90.
The nuts 346, 146, the bushing 251 and the sections of wire leading from the
annunciator disc to the switchboard unit and from this unit to the outgoing wire 90
are preferably covered with cement as already described in connection with the
back of the annunciator; the object being that all of these closely packed parts
may be protected against mechanical or electrical interference and disadjustment.
Each spring 130 has a slot 130¹ so located that when the tension of the spring
causes the V-shaped end to touch the pin 129, good contact will be insured and
the spring will also remain centered by the slot. A front plate 328, has a hole 329,
for each switch combination and suitable numbers are arranged in proximity to
the respective poles and these switches are located with respect to the annunciator
so that the distances between such switches and their relative locations will coincide
with those of the corresponding annunciator discs. For instance, if there were
15 rows of 10 indications in each row in the annunciator, then if the 7th disc from
the left on the 4th tier has been operated, the corresponding switch jack would be
located in the seventh space from the left on the fourth tier of the switchboard.
The switchboard as an entirety, is preferably located at the side (the left side)
of the annunciator, so that it will not only facilitate the rapid location of a switch
corresponding to an operated disc (the discs and switch units being arranged as
already described) but will also serve to protect the switches against the corrosion
or short circuiting which would follow a dripping of the annunciator fluid in case
of a leak in the tank if the annunciator were placed over the switchboard instead
of at its side. This general arrangement is preferably made so that the plane of
the front of the switchboard will be approximately that of the glass front of the
annunciator so that the backs of these two portions of the apparatus will be brought
into approximately one plane which facilitates the manufacture while the fronts
when so placed will enable the operator to perform his various duties in the most
expeditious manner which I have been able to devise.
In order to support the office apparatus and also to make it easy to obtain access
to the wires at the back, I mount the entire apparatus upon brackets 212, supplied
with pin hinges 213, fitting into holes in suitable lugs preferably cast upon corner
pieces 210, and all of these parts are preferably arranged so that the apparatus
may be swung out at either side at will.
An
A suitable plug 330, is arranged to co-operate with any of the switches; this
is illustrated in larger proportion so as to show the details of construction.
inner skin 336, terminates in a shank and forms a tube 334 adjusted to fit tightly
over any switch pin 129 and a metal block 338 serves to connect to it by means of
screws 339 and 340 the double conducting cord 132 and this is attached to contact
block "A." An insulating tube 332 separates the skin 336 from an outer tube or

page_text: skin 335 and this is connected with second block 341 which is connected by
screws 342 and 337 with a second double cord 131, which is attached to a block "B."
An insulating washer 333 separates the blocks 338 and 341; the wires of each cord
are doubled only for the sake of greater security against interruption in case of
the breakage of a cord. The plug is adapted to be inserted into any hole of the
switchboard, and to separate the corresponding spring from its post and thus to
disconnect the annunciator disc of the corresponding line while connecting the
line itself to the indicator and controlling mechanism.
The indicator itself consists of a step by step movement including an arbor 166,
wheel 108, magnet 109, armature 169 carrying the impelling pawl 175, arbor
bracket 255, indicating pointer 107 arranged to be carried step by step over the
ring 102 and dial 103, the latter being supported by the strips 319, 320 and 321,
in such manner that it may be readily removed without disturbing the ring 102.
A retaining pawl 177 is suitably mounted so that when rocked it will engage with
the teeth of the wheel to hold this in place in its various positions of rest, and
both this pawl and pawl 175 are so mounted that their free ends, which are heavier
than the engaging ends will cause the latter to take their proper positions when the
slide bar 181 is depressed and removes its projections 182 and 183 from engagement
with the pawls; a spring 104 carried by post 105 acts to hold this bar normally
in such engaging position by supporting the lug 184. This lug is adapted to be
carried downward by pin 27, operating in a slot 106 and carried by the operating
lever 30 of Fig. 11. The indicator parts are contained in an insulating box 202,
three of the corners thereof being fitted with metal contacts 203; and upon the
insulated back board of the supporting case 206 are carried the corner brackets 1
and 2, which act both to hold the indicator in place by means of the upright posts 3
springing therefrom and bearing fastened thereto the springs 159, 160 and 161
with which the indicator box corner pieces make contact when the box is inserted
in the brackets. These arrangements make it possible to take out and replace the
indicator or a substitute quickly and without liability of error.
The operating lever is suitably fulcrummed at its inner end upon the backboard,
and a suitable handle 34, enables the operator to depress it and to carry the pin 27
into position to cause it to free the engaging pawls and to permit the magnet to
rotate the wheel and pointer; while the reversal of movement throws the pawls
out of engagement and permits a suitable retracting spring (not shown) to reverse
the rotation of the wheel arbor and thus to restore the normal position of the parts.
Suitable adjunctive devices are supplied, such as a retracting spring shown as a
flat spring abutting against the magnet core, and such a spring and a support are
provided for the operating lever. The advantages of the novel arrangement
described are that the operating lever may be given a conveniently wide range
of movement while the necessarily close adjustment of the pawls and the teeth of
the wheel will be preserved, and no unduly rough handling of the lever can com
municate any jar to the more delicate wheel impelling parts as they are indirectly
or negatively controlled by their respective springs; and no unsteadiness while
the operator is holding down the lever can affect the operative condition of the
parts. I also cause the operation of the lever to control the necessary circuit
changer during the act described, by the following arrangements, and here again
I direct attention to the fact that the delicate contact adjustments are controlled
negatively, thus insuring the continuance of the close adjustments required for a
trustworthy operation even when the lever is operated carelessly. An insulated
block 189 and three springs 190, 191 and 193 form the circuit changer; this is
mounted within the indicator box. The central spring 191 is designed to be
moved directly while the other springs are given just enough resiliency to cause
good contact with the central spring as this is held in contact with one or the other.
The springs carry suitable platinum contacts 192. The normal position of the
springs is as shown in Fig. 13, and when the operating lever is depressed and the
bar 181 is carried down, a lug 188 carried thereby, is moved away from the con-

page_text: necting button 194 upon the central spring, and this permits this by its own
resiliency to break its normal contact and close the circuit with spring 190; thus
bringing the indicator magnet 109 into action; while the same act enables the
pawls to reach the wheel and continue its motion; while a simple reversal of the
movement of the lever restores all these parts to their normal condition and also
permits a suitable weight or spring (not shown) to restore the wheel and the
indicator pointer moved thereby. Suitable adjuncts, such as limiting stops, a glass
cover and a sash frame 325 are also provided. Fig. 13 shows the general circuit
arrangement when a number of such transmitters are located at sub-stations.
There are other ways in which the circuit may be arranged, but this form is very
simple and any troubles are readily located. In order to distinguish such trans-
mitters from other forms of automatic signal transmitters, I name
this form a teleseme. From each distant teleseme
a separate line as 89
and 95, called an individual wire leads to the central station. In addition
there are two general return wires, the one 134 called the teleseme wire, and the
other the annunciator wire. In order to enable crosses and other faults to be
readily located, I arrange the annunciator wire so that there is a separate branch
for each group of transmitters and as shown herein the transmitters are supposed
to be located upon different floors of a large hotel, and each branch will thus feed
one floor. Thus the branch 127 feeds the transmitters 110 and 153, branch 126
feeds transmitters 154, and 155, while branch 125 feeds transmitters 156, 157
and 123. This last floor is shown as supplied with an auxiliary testing switch-
board 119 having suitable switches 120, 121, and 122 for all of the wires, there
being also a sub-branch 124 designed to lead to transmitters located at another
spot. This arrangement is for hotels having many rooms on each floor. The
teleseme wire leads in like manner to the several groups by branches 139, 140
and 141, but these branches all lead directly into the main wire and are not con-
tinued separately to the central station as are the other wires described. In the
diagram all below the wire 139 is supposed to be located at the central station.
The several annunciator branches terminate in separate swing switches 21, 22
and 221, thus co-operating with the general contact 80, whence a testing switch 81
leads to the socket 811 when the said switch is closed; thence to the connection 46,
screw 45, wire 23, annunciator bell magnet 39 and connections 38, 43, 54 and 5,
to the battery switch 60. This switch is designed to co-operate with batteries 100
and 101, only one being required at a time and the other being in reserve for
instant use in case of accident. From the plus pole eof these batteries the wires 137
and 138 lead to the switch sockets 59 and 58 respectively, and in this manner the
battery switch is used to throw in either battery at will. The minus poles of the
batteries connect to the common wire 136 and then lead to the common plate 63
which carries switches 64 and 65, the first being connected with the teleseme
wire and the second by wire 1331, to test plate 99, wire 18333 to connection wire lead-
ing to the negative dises 98 which have already been referred to in connection with
the annunciator; the branches shown indicate how, in a large annun-
ciator, several such groups of negative discs may be connected at the
same time with the common wire 133. The individual wires when they enter the
office apparatus connect with the switch pin 147 and the spring 148 already
described as the spring jacks in the annunciator, and thence to the corresponding
annunciator discs as 96 and 97; (the disc corresponding to line 91 is shown in
side view).
From the point near the main battery switch a branch 4, leads to the contact 161;
thence to the indicator magnet 109 and spring 190 in the circuit changer, and in
the normal condition of the apparatus this line is dead, but it is energized when the
indicator is called into play. The circles 75 to 79 and 135 represent holes in the
back board for the admission of the respective wires from without.
The cord contact points "A" and "B" already described in connection with the
indicator are connected with the two other springs of the circuit changer by suit-

page_text: able strips fastened to the back board, one of them indicated by 48, 51, 52 and lov,
and the other by 47, 71¹ 19, 191, 16, 17 and 171.
The co-operation of the parts described is such that when a transmitting operator,
for instance, a guest in a hotel room, presses the push button 114 of his trans-
mitter 110 the circuit will be as follows. From the plus pole of the battery in
the office to the bell 24 and intermediate connections; whence, when the annun-
ciator switches are duly closed as they would be in practice, to branch 127, thence
by tap 128 into the room to the back contact screw of the block on the base of the
teleseme, thence by spring 115 and 115¹ to the push button spring 116, thence to
the contact on the base plate, thence by individual wire 89 to the switch jack com-
bination 147 and 148 in the central office, thence to the platinum disc 96, through
the electrolytic solution to the negative discs 98 in multiple and thence back to
the battery; while the current flows it causes the annunciator bell 24 to ring as
long as the button in the room remains depressed, and also decomposes the
electrolyte to cause a stain to be deposited upon the electrode as an indication of
the source of the call or signal. During this depression the push button has been
moved away from the top contact 113 which leads to the magnet 110 by way of
the wire 400 and, therefore, the transmitter will not be operated by the current,
but as soon as the push button is permitted to spring back, the magnet 110 is
As a pre-
again connected so that it may be operated from the central station.
caution against accidental opening of the main circuit, as well as to insure the
passage of the greatest amount of current possible, the annunciator bell 24 is
not an ordinary vibrating bell but is arranged so that the branches 40 and 43
will co-operate with the armature 41 pivoted at 57 and the spring contact 42
carried thereby, so that as the current flows through the magnet 39 and the
armature is attracted until its hammer strikes the bell 24 the circuit will not be
broken during the attraction as in an ordinary trembler bell, but the magnet will
be short circuited by the armature whereupon it will be de-energized and the
armature will be carried back by a suitable retractile spring (not shown) whereupon
the operation will be automatically resumed; these alternations of energization
and de-energization of the magnet will continue as long as the distant push button
is pressed. The polarities of the batteries are arranged as shown so that the
positive element of the electrolyte when decomposed will be deposited upon the
corresponding electrode disc.
When the receiving operator-the hotel clerk for instance-wishes to discover
at which signal the transmitting apparatus has been set by the guest, after the
bell has called attention to the fact of the operation and the discoloration of
the disc in the circuit has indicated the room, he inserts the plug in the proper hole
as already described, thus establishing the circuit connections shown in the diagram,
in which, for simplicity of explanation, it will now be assumed that the transmitter
which has been operated is connected to line 90. The insertion of the plug will
cause the annunciator disc to be cut out of circuit contact with the line, but it still
remains in connection with the line by way of a loop established and continued as
long as the circuit changer is permitted to remain in its normal condition in which
springs 193 and 191 remain closed. The object of this loop is that the plug may
be left in the hole corresponding to the room that has last called, as an indication
of such call, without preventing the normal operation of the line. This loop may
be broken by three devices, each one of which causes the battery current to flow
through the inner skin 336 of the plug and into the distant transmitter, while the
outer skin cuts off the now useless annunciator disc; these devices are, the main
lever, which as already described will cause the centre contact spring 191 to
transfer the contact from the normal branch 193 to the working branch or
spring 190; and the push buttons 85 and 86, the action of which will be described
hereafter. As soon as the operating lever is depressed it will act simultaneously
to transfer the centre spring in the circuit changer as already described, thus
causing the battery current to flow through the main switch 60, branch 4, indicator

page_text: magnet 109 and the contacts before described as connecting with cord 132, and
thence by way of the inner skin of the plug to the transmitter on line 90 (the
magnet 153 corresponding to 110 of line 89 and of Fig. 4) thence through the break
spring and break wheel to branch 139 of the teleseme wire 134 and thence back
to the battery; and the flow of current will cause the energization of the transmitter
magnet and the consequent release of its clock work and rotation of its break
wheel; and the impulses produced during such rotation will be recorded by the
step by step indicator controlled by its magnet 109. Of course, any other receiving
apparatus may be used and the transmitter itself may be widely varied. When
the cessation of impulses shows the clerk that the transmitter has run down he
permits the operating lever to return to its normal position, thus restoring the
circuit changing spring 191 and permitting the pawls of the indicator movement
to disengage the wheel, which, under stress of its spring will return the pointer 107
to its position of rest. The transmitter will remain as set until the clerk thus con-
trols it and the fact of its release shows the guest that his call has been noticed.
The contact screws or nuts on each transmitter are shown in their proper order
in connection with the transmitter just referred to, A representing annunciator
wire, I that of the individual wire and T that of the teleseme wire.
Suitable dial arrangements enable the clerk to recognize the signal and among
improvements in such arrangements I specify the following. The dial ring 102
of the indicator, already referred to, bears suitable numbers from 0 upwards in
sequence, according to the number of columns on the transmitter, and over this
ring is a second plate with a series of numbers arranged in columns, those in each
column beginning with a digit which is one number higher than that above it on
the ring, and continuing in sequence in a column toward the centre for as many
steps as there are concentric rows of indications on the transmitter. A further
improvement is to print in the corresponding spaces of this dial the words corre-
sponding to those on the transmitter dial.. The manner of using these dials is as
follows, it being remembered that every signal consists of two sequences of impulses
separated by the pause produced by the passage of the long tooth on the transmitter
break wheel-The clerk notices at what number on the outer ring the pointer 107
pauses during the rotation of the indicator wheel, and this pause will correspond
with the starting position of the transmitter pointer arm with respect to the
columns on the transmitter dial. The clerk will furthermore notice the final pause
which begins when the break wheel in the transmitter can no longer operate
because the pointer has been stopped by one of the steps of the rib, and which will
continue indefinitely until the clerk re-opens the circuit by restoring his lever
and he will then look for the correspondingly numbered space in the column which
he has before noted as indicated by the first pause. Printed across that number will be
found the word selected by the transmitting operator. For instance, if the guest
had set his pointer at H, of Fig. 1 which is located in the eighth column and first
space (the columns being numbered clockwise and the preceding columns not
being shown on the drawing) the break wheel in returning would first produce
eight impulses and the receiver magnet would thus indicate No. 8 (the first step
marked being controlled by the mere closure of the circuit). Then the pointer
would pause and then move one step further because the transmitter could only
move the wheel one tooth further before the final engagement of the transmitter
sliding arm on the outer or front step of the rib; and, as the first indication of
column eight of the inner dial of the indicator is marked nine, it will be possible
to print on this space of the indicator dial the letters H, or any other word corre
sponding to the indication selected and marked in the corresponding space of the
transmitter, and to read off this indication without any further calculation. In
like manner in case of the selection of indication J, on the transmitter, the pointer
would have moved first to No. 10 and then to No. 14, whereas for indication J₁,
the pointer would have moved first to No. 10 and then only one step more to No. 11.
This arrangement is in practice most effective and simple and dispenses with much
complicated mechanism heretofore devised by me for this purpose.

page_text: It is obvious that with this arrangement if the pointer has been moved to an
adjoining space by accident or carelessness there will be no means for indicating
this fact at the receiving station where the signal can only be read as received,
and I consider a very important improvement to be the following simple means
by which I have provided a safeguard against errors of this kind. By arranging
the signals only in alternate spaces of the dial I am enabled to secure a very effec
tive check, or, rather, a greatly increased probability of discovery of error, for the
reason that the receiving indicator will operate the full number of steps, and in
case of any error of this nature the clerk would notice the variation between the
signal actually received and any signal which could probably be sent and he would
thus be aware that the transmitter was either out of order or that the guest had
inadvertently left the pointer upon a blank space. This very simple expedient is
of great importance in practical operation because it serves as a check, which,
in practice, is sufficient to cause absolute confidence to be reposed in the recep-
tion of a signal which operates normally, and directs special attention when any
abnormal indication is received.
The general arrangement thus described enables one indicating apparatus to be
joined in turn with any number of transmitters, and it makes it possible for any
number of transmitters to be operated at the same instant without confusion, as
each signal is released and received successively and a guest need not wait to
discover whether the system is in use by others.
Provision is also made for causing the teleseme dial or any other suitable device
actuated by the armature, to receive signals of two kinds from the central station
the one comprising single taps on the transmitter bell, and the other continuous
vibrations, as follows:-
From the main battery switch 60 a third branch, 7, 8 and 9, with its screws 71
and 91 leads to the magnet 10, thence by wire 14 and screw 88 to the strip 15
where it ends at the contact 162; a branch connection leading to the arma-
ture 11, which normally rests against contact 12, whence it leads through 87
and 13 to contact 163. The bridging pieces 191 and 171 and the back contacts 17
and 191 co-operate with the push buttons 85 and 86 (shown also in Fig. 10 as
surrounded by suitable bushings 326 and 327) in such manner that when
button 85 is depressed it breaks the cord loop already described and connects
the cord, and hence the out-going line to which it is then attached by the plug
to the battery through the contact 162 and magnet 10 with the result that with
every depression of the button a single tap is given upon the bell in the trans-
mitter; while the magnet 10 serves to show that the circuit is intact, inasmuch as
its armature will also respond. But when button 86 is depressed the same result
will be obtained as to the general circuit, but, inasmuch as the current neces-
sarily passes through the armature and this is attracted at each energization of
its magnet 10, a trembling or vibrating operation of the circuit will be pro-
duced, and continued as in a trembler bell as long as the push button is kept
depressed. In this way, in a hotel of several hundred rooms a vibrating bell
effect is produced in the rooms while only the single set of contacts belonging to
the magnet 10 is used and as these contacts are located in the office they may be
readily inspected and kept in order. In addition to this great simplification of
apparatus the vibration of the armature 11 acts as before to indicate to the clerk
that the circuit is intact. The push buttons are shown as controlling levers 16
and 18, fulcrummed at 71 and 71 respectively, but, of course, any other arrange-
ment will suffice.
In connection with the disc of line 93 arrows are shown to indicate the course
of the current which flows during the closure of the push button in the trans-
mitter. During this flow not only do all the negative discs as 150 and 151, but
every other positive disc the circuit of which is not at the moment opened at the
top contact of its push button by the operation thereof, will also act as a negative
or return path for the current, because the circuit leads back through other indi-

page_text: vidual wires through the top contacts of their push button springs and thence
through their magnets and break wheels, and although the resistance
of one magnet is comparatively large, the joint resistances of several
hundred of these would be SO
small that practically a large portion of
the current which returns to the negative pole will pass in this manner. This
arrangement is very important as it causes a continued electro-chemical action
upon the discs tending to keep them bright. It will be noticed that the indi-
vidual wires and the teleseme wire correspond to one pole of the battery, while
the annunciator wire connects to the other pole, and it is obvious that if the
annunciator wire and the teleseme wire should become crossed by means of the
sub-branches in any of the rooms, all the individual wires might be short-cir-
cuited, and the object of dividing the annunciator wire into sub-branches is to
make it possible to locate such trouble more readily, as by a progressive sub-
division of the annunciator wire in connection with tests of the respective indi-
vidual wires the faulty portion may be readily located.
An additional provision for use in case of accident is the short length of hard
rubber tube formed into a plug shown as 343 in line 92 of Fig. 13. This is of
proper size to be inserted in any hole in the front plate of the switchboard and
thereby to separate the two contacts of the corresponding switch-jack and thus
permanently to break the line and prevent a constant ringing of the bell and a
deposit upon the corresponding disc in the event of a permanent cross or pro-
longed depression of the button of the transmitter. Suitable holes 344 and 345
are provided in front plate of the switchboard for inserting these plugs when they
are not in use. The front plate of the switchboard is placed at a suitable distance
above the various spring jacks to enable this safety plug when thus inserted to
thus open the circuit at the same time permitting the collar to remain exposed
above the hole so as to enable this devicesto be readily removed when desired.
The apparatus embodies various minor improvements as follows: The trans-
mitter dial is preferably arranged so that the outermost surface consists of a
sheet of transparent and flexible substance, such as celluloid; the indications are
printed upon a sheet of paper of proper shape and preferably arranged more or
less like an open fan, so that when the ornamental frame is removed a new dial
may be substituted merely by lifting up the flexible celluloid and inserting the
new dial, there being no need for the removal of the rib, pointer arm or other
attachments.
It is evident that the transmitter need not, in every instance, be enclosed
within the wall box, or sunken into the wall, and when this is not required, the
base plate will be modified so as to be shaped somewhat like that shown in rough
diagram as 123 of Fig. 13, and, even if a wall box is used, this need not neces
sarily embody the devices described by which the main portion may be imbedded
in the plaster during the period of construction of the building, while the adjust-
able portion which contains the contact devices is adapted to be added later at any
convenient time, and by reason of its construction is adapted to remedy any mis-
placement either as to depth or as to direction in the plane of the finished wall.
The annunciator solution is improved by the used of sugar, not only chemi-
cally as described, but the stain may be made to remain upon the disc longer by
reason of the greater density or viscosity which can thus be given to the liquid;
and I have found that when good ordinary cut or loaf white sugar is dissolved
in water in proportions to secure the density which a particular installation may
be judged to require it is advisable to heat the solution to about the boiling
point for a few seconds but not more, because if heated too long it will tend
to discolor, while if not brought to the boiling point certain samples may display
a tendency to recrystalize as the solution becomes thicker from evaporation.
It is desirable to proportion the hole or holes through the bubbles are forced
into the solution so that these bubbles will be large enough to occupy the entire
space between the front glass and the discs, as I find this hastens the dislodge

page_text: One
ment of the stain. I also arrange to provide some means for escape of air from
the tank during the act of blowing into the solution, and this may, if desired,
be a vent hole on the top. I have used this hole as a point of entrance for a
suction tube when it is desired to empty out the solution for the purpose of
cleansing the tank or removing an exhausted solution, but I find that the appa-
ratus is greatly simplified if the neck of the blower tube is so arranged that the
blower may be detached and the exhaust tube substituted when necessary.
advantage of this is that the front glass may be placed very near the discs, thus
giving a very thin film of solution which will permit the discs to remain clearly
visible much longer than with a film or depth thick enough to admit a suction
tube of sufficient bore to exhaust the viscous liquid by the well known labora-
tory method of the continuous syphoning action at normal atmospheric pressure.
This decrease in space also causes the air bubbles to be flattened so as to cover
a larger area as they rise during the act of blowing away the stains.
The indicator box may be advantageously kept level by means of suitable posts
as 36 of Fig. 11.
The tag 502 is suitably inscribed with the caution not to use that end for
pointing; as, for instance, "point with other end."
It will be noticed that a pin on the cam 437 could also be used to engage
with the armature point, but the edge of the tooth cut in the cam practically
serves the same purpose and gives a larger margin of adjustment for the bell-
hammer.
a
The transmitter as arranged when at rest is upon closed circuit, but it is often
desirable to cause it to rest at open circuit, as, for instance, in order to produce
permanent break as a check upon the correct operation, or for use in an ordinary
bell-wire circuit; and I have devised a simple way for producing such a final
break and also for changing the adjustment of a transmitter so as to adapt it to
remain, at will, either upon an open or a closed circuit at the end of the operation.
One form of adjustment for this purpose is shown in Fig. 1 by the hole in the
rib to the right of the screw 523. When the rib is rotated upon its bearing upon
the central hub far enough to the left to permit screw 523 to pass through this
hole and into the tapped hole 522 and thus to anchor the rib to the dial, the rib
will have been moved so far to the left that it will stop the pointer in a position
which leaves the brush over a space instead of over a tooth as in the adjustment
heretofore described.
Reference has been made to the orifice through which the air bubbles rise in
the annunciator. In a tank of more than about six inches in width there should
be several such orifices and these are preferably arranged about an inch apart
and graded in size so that the smallest-about one sixteenth of an inch in
diameter is nearer the bulb and the others are each about double the size of
the preceding one.
The white background for the discs is of glass and the numbers identifying the
respective discs are enclosed in glass tubes so as to resist the exceedingly corro-
sive action of the deposited iodine.
When the transmitter dial is arranged with indications in alternate spaces only,
the indications on the dial of the receiving indicator will of course be arranged
similarly, and in this case the index numbers may or may not be placed in the
blank spaces.
The rib of the transmitter is preferably arranged at an angle to the dial-
the highest point being at the outer edge so that the apparatus may be made as
flat as possible in view of the fact that the greater leverage of the arm when
extended would make it possible for a careless operator to lift the pin over the
rib and thus change the main spring tension; if this rib were as low at the
outer end as it can safely be made at the inner end where the sleeve would confine
the arm to its proper level.

page_text: 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. A wall box adapted to be locked into a partition, in part below the surface
thereof, and comprising a guiding device and contact terminals co-operating with
a signal transmitter adapted to fit therein and having terminals placed so that
they join the wall box terminals when the transmitter is guided and fitted into
the box, together with a locking device for holding the parts joined.
2. A wall box adapted to be fixed to a partition and a transmitter adapted to be
fixed to the wall box and means for changing the alignment of the transmitter
without moving the wall box; whereby errors in alignment of the wall box may
be remedied.
3. A wall box comprising one part adapted to be plastered into a wall, and a
second part adapted to be fitted into the first, a transmitter adapted to be fitted
to this second part and a locking device for joining the second part and the
transmitter.
4. A wall box including a piece adapted to be locked into a partition and a
co-operating second piece having three points supporting or attaching it to the
first piece; whereby the second piece may be adjusted into in and out of align-
ment with the wall in case of improper alignment of the first piece.
5. A wall box comprising one part adapted to be placed into a wall, and a
second part adapted to be fitted into the first but insulated therefrom, and a
transmitter adapted to be fitted to the second part.
6. A wall box comprising one part adapted to be received to a wall, a second
part insulated therefrom and carrying one or more circuit terminals; a trans-
mitter adapted to be fitted to the second part and including terminals adapted to
join the first named terminals when the transmitter is so fitted.
7. A wall box comprising a metal frame adapted to be plastered into a wall
and provided with rocking extensions and having insulated bearings for fastening
a second piece of metal and insulating it from the first; a transmitter adapted
to fit into the second piece and devices for locking, this second piece and the
transmitter.
8. A wall box having one piece adapted to be plastered into a partition and a
second piece adapted to fit into the first, and shaped and proportioned to permit
of adjustment after the first piece is fixed by the plaster, and means for per-
manently locking the second piece when adjusted as desired.
9. A wall box having a piece adapted to be plastered into a partition and a
second piece adapted to fit into the first, and shaped and proportioned to permit
of adjustment in the plane of the wall as well as in an in and out direction;
together with devices adapted to fasten these parts when the latter is suitably
adjusted, and means for insulating one from the other; joined with a trans-
mitter arranged to fit the second piece and to be locked thereto.
10. A wall box adapted to be plastered into a partition and a transmitter
adapted to be fitted to the wall box and including a dial face and frame project-
ing beyond the wall box; mechanism under the dial; together with devices
formed, adjusted and proportioned to permit the back of the frame to lie closely
against the partition surface and means for locking and unlocking the trans-
mitter, controllable from the front side.
11. The sleeve with the extension as a support for the arm, and the extension
at right angles thereto for supporting it upon the arbor.
12. The arm with its sleeve support and the spiral spring arranged to hold it
where placed, and working in alignment with the supporting arbor.
13. The sleeve provided with means for fastening it to the arbor by the screw
working within the same and combined with the plunger and spring working in
the line of the arbor.
14. The arm having the position holding notches at the bottom, and a spring
co-operating therewith to hold the arm where placed.

page_text: 15. The arm having the downwardly projecting pin, adapted for use both to
designate a chosen indication and to bear against the several steps of the rib,
and the rib lying in a plane at an angle to the dial.
16. The rib, with means for fastening it to the dial plate, whereby it may be
removed or adjusted without displacement of the dial frame.
17. The rib provided with fastening devices for causing the transmitter when
run down to remain on open or closed circuit, as desired.
18. The clock work comprising a main arbor upon which is mounted the break
wheel having a given number of divisions and another arbor having a cam,
together with intermediate gearing causing the cam to make one revolution for
every such division traveled by the wheel, together with the locking device, con-
trolled by the armature of a magnet and adapted to engage the cam at its
several revolutions.
19. The armature having a hook projection for engagement and the cam formed
to engage the hook at a certain position and to hold the armature in a given
adjustment at another position during its revolution.
20. The magnet controlling both the release of the transmitter and the ringing
of the bell.
21. The magnet controlling both the release of the transmitter and the ring-
ing of the bell, combined with means for preventing the bell from ringing while
the transmitter is running down.
22. The magnet controlling both the release of the transmitter and the ring-
ing of the bell combined with the cam and armature formed and adjusted to
permit the bell to ring only during a certain position of the cam.
23. The transmitter magnet; the armature with its hook and the bell hammer
extension, together with a bell and the hammer arranged to be protected by the
bell and to strike it on its inner side, and the cam preventing the full range
of the hammer motion at certain positions thereof.
24. The transmitter movement and magnet with its surrounding protecting
case the bell mounted externally thereto, and the opening in the case through
which the hammer projects.
25. A transmitter break wheel having metal teeth; a co-operating resilient
circuit brush; combined with means for preventing the brush from dipping
between the teeth; together with an abutment placed so that the brush may be
limited against greater displacement away from the teeth than is required for its
contact function; whereby the brush during adjustment cannot be bent beyond
its limit of resiliency.
26. A transmitter break wheel having metal teeth and a protecting plate at
the bottom insulated from the teeth and adapted to limit the range of motion of
a contact brush mounted to co-operate with the wheel.
27. A transmitter break wheel having metal teeth and a protecting plate insu-
lated from the teeth; a contact brush co-operating with the teeth and mounted
to bear resiliently against the teeth and the plate simultaneously, and means
for removing or adjusting the wheel without displacing the brush from its
support.
28. A transmitter break wheel at one end of an arbor and at the other end a
support for a sliding arm located over a dial whereby the break wheel may be
adjusted and inspected without disturbing the arm and dial.
29. An arbor in a transmitter arranged to receive at one end a detachable break
wheel and at the other end the detachable arm and means for fastening the arm
to the arbor by a screw entering the arbor.
30. The arbor supported at one end by the frame plate, combined with the
friction plate mounted upon this frame plate, and carrying the main spring, the
other end of which is carried by a loose ratchet bushing and on the other side
of the main plate the counter spring and the break wheel.

page_text: 31. The friction plate having a portion bent up as an anchorage for the min
spring.
32. The counter spring placed between the break wheel and the main plate
and in combination therewith.
33. The sliding arm combined with the counter spring whereby the pointer pin
will be held in the centre of a column.
34. The broad faced ratchet engaging with the oppositely placed pawls com-
bined with the lock plate supporting one pawl fixed on the arbor, the second pawl
on a gear wheel supported loosely on the arbor; together with the friction plate,
and the main spring fixed to the said plate and the ratchet.
35. The armature and the cam supporting arbor pivotted between the move-
ment supporting plates, and the magnet mounted upon one of the plates, cem-
bined with the armature projection and the cam engaging therewith.
36. The break wheel located outside of the frames and a magnet mounted on
one of them, combined with the brush and its support, together with means for
supporting this so that it lies over the magnet.
37. The cam bushing combined with adjustment screws whereby it may be
fixed after being rotated into proper adjustment.
38. The adjustable cam combined with the adjustable break wheel, the adjust-
ments being placed so that the clock work need not be taken apart or removed
from the supporting base for adjustment
39. The direction tag at one end of the arm with its downwardly extending
lug all formed so that when the arm is fully extended the tag will be located over
the sleeve.
40. The casing for the movement of the transmitter, combined with a supple-
mental piece formed and arranged to be removed to give access to the cam for
adjustment.
41. An electric push button comprising a support for two way contact springs
and extensions thereto, and a button on the front of said support and guiding
devices, combined with a fixture adapted to be fastened to the wall and including
insulated terminals for three wires of the circuits to be controlled by the button
together with means for locking these parts and simultaneously establishing the
connection between the respective contacts.
42. In a signal transmitter an internal circuit loop comprising in sequence, a
contact terminal, its spring, the break wheel, its brush, the magnet, a normal
top contact for a movable push button element, and the said element.
43. The arbor, the sleeve and the arm, combined with a device for locking the
sleeve to the arbor located so that it can only be unlocked after the removal of
the arm.
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44. The transmitter comprising an arm adapted to be moved radially and longi-
tudinally, mechanism for holding it at rest at the points where these lines of
motion intersect, means for producing signals distinguishable for each such posi-
tion of rest, combined with a dial over which the arm is thus movable, bearing
indications and blanks, alternatively, at the intersecting points, so that the signal
received will show whether the arin has been correctly placed or has been, in
error, placed in the space adjoining the one intended, whereby error
obviated.
is
45. The dial support, the rib attached thereto, the fan shaped indication bear-
ing dial combined with the transparent flexible cover, and the frame holding this
down, whereby when the frame is removed, the dial may be inserted without
disturbing the adjustment of the mechanism or removing the rib.
46. The indicator comprising the step wheel, the pawls normally out of adjust-
ment combined with the circuit changer, and the operating lever arranged to
throw the pawls into adjustment and simultaneously to control the circuit changer
when the lever is moved in one direction, and when reversed, simultaneously to
restore all these parts.

page_text: 47. The removable indicator mechanism and magnet mounted upon a support,
guides for holding these parts in place with relation to the rest of the mechanism,
and the operating lever adapted to engage therewith after it is placed
in position.
48. The removable indicator and magnet mounted upon a support; guides for
the indicator, contacts upon the support; co-operating .contacts on the back
board, combined with the operating lever; all co-operating so that the electrical
and mechanical, parts are properly brought together by the act of inserting the
support in its guides.
49. The indicator comprising the step wheel, the pawls, the operating lever
and means controlled thereby and adapted to hold the pawls out of engagement
with the wheel positively, and to control their engagement only negatively,
whereby when the lever is so moved, the pawls will be engaged by an action
which is independent of variations in the force applied to the lever.
50. An indicator comprising a magnetically controlled pointer; a dial bearing
indications duplicating those of the transmitter and arranged in radial columns;
and series of index figures corresponding to the indications and arranged in
sequence for each column.
51. An indicator for use with a transmitter arranged to send two sequences of
signals and comprising a magnetically controlled pointer; a dial bearing indica-
tions duplicating those of the transmitter and arranged in radial columns; and
series of index figures for the indications arranged so that each column bears a
characteristic figure and under that figure and with correspondence with the indi-
cations in that column are arranged the figures characteristic of the succeeding
columns.
52. In the annunciator the air duct formed in the base plate.
53. In the annunciator the air duct formed in the base plate and the gasket
forming a part thereof.
54. In the annunciator the glass tubes containing the number strips.
55. In the annunciator the separate number strips and their supporting devices.
56. In the annunciator the electrodes or discs comprising a sheet of platinum
mounted on a rubber cushion.
57. In the annunciator the independent clamps formed and arranged to clamp
the back plate and the glass with the rubber packing between them.
58. In the annunciator the orifice of the air duct arranged to be used both
for the blower and for an exhaust tube.
59. In the annunciator the glass and base plate with the rubber gasket clamped
between them; the latter extending from the glass to the plane of the base on
which the discs or electrodes are mounted.
60. In the annunciator the solution comprising sugar dissolved in water.
61. In the annunciator the solution comprising sugar and potassium iodide dis-
solved in water.
62. In the annunciator the connecting plates fastened to the back of the base
plate and provided with fastening devices both for the wire leading to the disc
and for that leading to the outgoing line; together with a covering of plastic
material over all the wires and plates.
63. The switchboard spring jack comprising a pin, and a spring bearing against
it and fitted with the notch 130¹.
64. In the annunciator the white background formed of strips of vitreous
material locked in place by the discs and their wires.
65. The electric signal system comprising a magnet controlled transmitter at
each sub station, a separate line from each to the central station and two return
wires each having a branch to each sub station; a co-operating source of current
-as a battery and from one of its poles, connections in multiple to an annun-
ciator bell and an indicator magnet; and, at the central station a switching ter-
minal for each distant station line, and a switch adapted to be used in common by

page_text: each such line together with means for connecting such line through the switch
with the annunciator bell and the indicator magnet in turn.
66. The mechanical elements of the operating lever combined with the inde-
pendent electrical elements of the circuit changer.
67. The circuit changer comprising two fixed contacts and an intermediate
movable contact, a locking device for holding the latter normally against one of
the fixed contacts; means for removing this device and means for causing the
intermediate contact to leave the first and engage the second independently of
the locking device.
68. The switchboard comprising the independent switches, combined with the
front plate with its guiding holes, and the tubular plug.
69. The plug loop circuit combined with the circuit changer and indicator.
70. The double tube plug with the two double cord attachments, substantially
as described.
71. The fixed operating lever, combined with the detachable indicator and cir-
cuit changer, together with the guiding devices and automatic contacts acting to
bring these parts into correspondence when the indicator is inserted.
72. The switchboard comprising the base upon which the springs are fixed,
combined with the pins fixed to and passing through the base, and the cement
protecting the back connections thereof.
73. An annunciator tank as described combined with a switchboard arranged
at the side thereof and substantially in the same plane, the respective units of
annunciator and switchboard being located in correspondence whereby upon
the actuation of an annunciator disc the corresponding switch may be most
readily found and in the event of a leak in the tank the switchboard will be
protected.
74. The annunciator fluid comprising an aqueous solution of potassium iodide,
sugar and sodium sulphite.
75. A signaling system comprising the magnetically controlled transmitters at
sub-stations, lines to the central station, a switchboard and annunciator in
series in each line, an indicator common in turn to the lines through the respec-
tive switches, an operating lever arranged to control the operation of the indi-
cator as well as of a circuit changer, and a connecting circuit plug controlled
by the said circuit changer and arranged not to interrupt the normal operation of
a circuit while the plug is connected to the corresponding switch.
76. In an indicator a progressively moving device, a magnet controlling the
same, a circuit changer controlling the magnet and having a definite range of
movement, combined with an operating lever having a greater range of move-
ment; together with a manually operated switching device adapted to connect the
indicator to any desired one of several circuits.
77. In an indicator a progressively moving wheel, locking devices engaging
therewith, a mechanical part controlling this locking device and having a definite
range of movement, combined with an operating lever having a greater range of
movement; together with a manually operated switching device adapted to con-
nect the indicator to any desired one of several circuits.
78. In an indicator a step by step wheel, a retaining pawl engaging there-
with to hold it at the last step to which it has been moved, a controlling element
therefor, having a definite range of movement, a magnet for the wheel, a circuit
changer for the magnet and a controlling device therefor, combined with an
operating lever having a range of movement greater than that of the said con-
trolling elements; combined with a manually operated switching device adapted
to connect the indicator to any desired one of several circuits.
79. Several magnetically controlled transmitters on separate lines, a receiving
indicator for the signals thereof, a switch for connecting the same to any trans-
mitter, an annunciator indication for each line, combined with the circuit changer
operating first-when at rest-to connect a line which is switched in with its

page_text: annunciator indication, second-when operated-to connect the indicator to that
line and to control the transmitter magnet and third-when restored-to restore
the normal conditions of the line and of the indicator.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.