IMPROVEMENTS IN APPARATUS FOR VISUALLY INDICATING ELECTRICAL SIGNALS
Year: 1882

page_text: LETTERS PATENT to Benjamin Joseph Barnard Mills of the firm of Harris
and Mills of 23 Southampton Buildings in the County of Middlesex Patent
Agent for an Invention of IMPROVEMENTS IN APPARATUS FOR VISUALLY
INDICATING ELECTRICAL SIGNALS Communicated to him from abroad by
James Urquhart Mackenzie of the City County and State of New York in
the United States of America
PROVISIONAL SPECIFICATION left by the said Benjamin Joseph Barnard
Mills at the Office of the Commissioners of Patents on the 12th September
1882.
BENJAMIN JOSEPH BARNARD MILLS of the firm of Harris and Mills of
23 Southampton Buildings in the County of Middlesex, Patent Agent IMPROVE-
MENTS IN APPARATUS FOR VISUALLY INDICATING ELECTRICAL SIGNALS.
A com-
munication to me from abroad by James Urquhart Mackenzie of the City, County
and State of New York in the United States of America.
The object of the present invention is to produce an electrical visual indicator,
capable of use for all the purposes to which such an instrument may be applied,
which will be exceedingly cheap, simple and compact in construction, absolutely
reliable in operation, and possessing such durability that it will not readily get out
of order in any of its parts; and which further, by reason of its cheapness,
compactness and reliability, will be adapted for many uses to which the visual
indicators heretofore produced could not be applied such as for indicators for
telephone exchanges, district telegraph service, hotels, or for other similar uses
A further object of the invention is to produce an electrical indicator of this
character, more especially designed for uses of the nature before specifically set
forth, which will be capable of being substituted for the ordinary electrical
annunciator drop, and will not only indicate the person who calls, as does the
ordinary annunciator drop, but will also show who or what is wanted, thus
resulting in a great saving of time and increasing largely the convenience and
efficiency of the service, whatever it may be, as well as economizingly permitting a
reduction of the staff of attendants.

page_text: The mechanism employed is enclosed in a suitable case, covering and protecting
the parts. This case supports two binding posts to which the line wires are
attached.
The operating electro-magnet is enclosed within the case. Only one magnet is
used to operate the mechanism.
It acts upon an armature carried by a lever which is retracted by an adjustable
spring. To this armature lever is pivotted a link which is connected with an arm
projecting from a rock-shaft.
This arm is preferably one of a number of pallet arms carried by such rock-shaft,
there being one of such arms for each section of the indicator.
Such arms project upwardly from the rock-shaft and carry pallets on their upper
ends, which pallets engage with the teeth of vertically sliding escapement racks,
one of such escapement racks being provided for each section of the indicator.
Each of these racks is slotted vertically and has a set of working teeth on the
edges of its slot, the teeth on one side of the slot alternating with those on the
other as will be well understood.
"
Below the lowermost working tooth is a "safety tooth' on the escapement racks
of all the sections which prevents the release of the locking device of the escape-
ment rack, should the rack of the preceding section be locked, when the circuit is
in other than its normal condition. This "safety-tooth" has no function on the
first section, since there is no preceding section.
Each escapement rack is provided on its rear edge with locking ratchet teeth
raking downwardly, such teeth being (at least) equal in number to all the
escapement teeth of the rack.
To the front of each escapement rack is attached so as to work therewith, a cog
rack which preferably has sufficient weight to carry the rack downwardly with
rapidity and operate the character wheels, which are mounted upon short shafts
carrying pinions engaging with the cog-racks just mentioned.
To guide the escapement racks in their vertical movement, the rear of each rack
slides in a groove in the face of a post, while the arms that support the cog-rack
from each escapement rack have holes through which pass vertical rods. In a slot
in each of said posts is pivotted a locking and lifting hook which is secured to a
rock shaft extending to the next succeeding section, if there is one, and there
carrying a supporting hook. Each rock shaft has a weight secured eccentrically
thereto, which throws the locking and lifting hook normally out of engagement
with the teeth of the escapement-rack with which it operates, and the supporting
hook normally under a pin on the side of the succeeding escapement rack.
All the escapement racks except that of the first section, are provided with a
pin, engaging one of the supporting hooks, while the shaft which carries the
locking and lifting hook of the last section has no supporting hook, since there is
no succeeding escapement rack to be held out of action while this last section is
operating.
Each of said shafts is turned against the counteracting force of its eccentrically-
secured weight, by another weight which is released when the escapement rack
begins to drop, but whose movement is retarded so that the escapement rack can
reach the limit of its movement and come to a state of rest on the pallet before it
will be locked and raised from said pallet. The weight in this mechanism is
furnished by pivotted segments, which have fingers engaging with the backs of the
lifting and locking hooks and forcing them in succession into the teeth on the rear
edges of the escapement racks, locking and raising such racks and releasing the
succeeding ones.
Each segment has cog-teeth engaging with a pinion on the shaft of a fan which
retards the movement of the segment.
Each fan is somewhat heavier on one side than on the other, which heavier side
is brought uppermost when the parts are set for action, so that when the segment
is released the overbalanced fan will instantly start the movement.
Each segment has also a pin which engages with a hooked lever pivotted to one

page_text: of the grooved posts, and over-weighted at the end opposite the hook so as to
disengage the hook from the pin.
The weighted end of the hooked lever is raised by the escapement rack but the
dropping of the rack allows the weight of the hooked lever to disengage the
weighted segment.
The hooked lever has however sufficient play to allow the escapement rack to
drop from its "safety tooth" to its lowermost tooth without releasing the segment.
Each of said hooked levers is limited in its movement by a plate, in order to
prevent its displacement should the box containing the mechanism be turned upside
down in handling.
The joint operation of the parts thus far described is as follows, it being under-
stood that the character wheels are provided with numbers, words or characters
which are exhibited at an opening or openings in the front of the box and it being
further understood that the instrument is in connection with a suitable transmitter
adapted to act with it.
Normally the escapement rack of the first section has its lowermost working
tooth resting on its pallet, while the escapement racks of the other sections are
raised off of their pallets, being supported by the hooks provided for that purpose.
The armature lever is moved by the action of the magnet and retracting spring
and the vibrating pallet allows the escapement rack to fall a definite number of
teeth, depending upon the number of times the circuit is closed and opened, when
it will come to rest on the pallet.
This movement will turn the character wheel, which has an intermittent
movement similar to that of the rack, since it is moved directly thereby, as well as
being controlled in its movement by the rack. The drop of the escapement rack
allows the weighted end of the hooked lever to drop and the weighted segment is
released, it being started by its own weight, and that of the overweighted fan, and
the movement being retarded by the fan.
The finger of the segment strikes the locking and lifting hook, and forces it
into the rear teeth of the escapement rack, raising such rack slightly so that it will
clear the pallet and allow it free movement.
The turning of the rock-shaft against the eccentrically supported weight
withdraws the supporting hook from beneath the pin of the next succeeding
escapement rack, and allows the second rack to drop upon the pallet.
If the first escapement-rack was locked with the circuit normal (either opened or
closed according to the arrangement) the second rack will drop until the lowermost
working tooth rests on the pallet; otherwise the "safety tooth" will be caught by
the pallet, which will be supported until the normal condition of the circuit is
restored, when the pallet will go over to the lowermost working tooth and the
section will be ready to act. This operation continues through as many sections
as are used (one or more) the only difference being that the last section is simply
locked without releasing any other section.
When the action has ceased, the complete signal will appear at the opening or
openings of the box.
To restore the parts to their normal position the following devices are used;
A push button is connected by a rod and arm with a rock-shaft which is pro-
vided with a number of weighted wings (one for each segment).
These wings engage with projections on the segments above referred to, and
when the button is pushed inwardly are raised and restore the segments to an
elevated position. The rock shaft also has loose arms which engage with pins on
the escapement racks and raise such racks, the loose arms being lifted by pins on
the weighted wings just mentioned.
The arms do not commence to raise the racks until after the wings have started
the segments, so that the segments will reach their position before the racks raise
the hooked levers to lock such segments.
At the same time that the segments are raised, the rock shafts which carry the

page_text: hooks are released and their weights withdraw the lifting and locking hooks from
the teeth and move the supporting hooks under the pins which engage there with.
The weight of the wings and arins returns the restoring devices to their normal
position, leaving the parts ready for action.
Instead of having a cog-rack on the front of each escapement, and moving a
wheel carrying the characters, numbers, letters or words, the characters may be on
a plate or strip carried directly by the escapement racks.
This form may be used, although the wheels are preferred, since much larger
characters can be used in the same space with the wheels than with the plates or
strips.
The instrument hereinbefore described is a complete indicator adapted for all uses
to which such instruments may be applied.
For some purposes, the opening (or openings) in the front of the box, is closed by
a pivotted or sliding shutter or drop, which is arranged to disclose the opening and
to itself display or uncover a number, word or character, when dropped down.
The drop has a hook at its upper edge, projecting through an opening in the
box, when the drop is raised, and engaging a pivotted locking arm within the case.
This arm drops by its own weight into engagement with the hook locking
the drop.
It is raised to release the drop by an arm on the shaft of the last section. This
arm strikes the locking arm at the same time that the escapement rack of the last
section is locked and the drop is thus allowed to fall only at the completion of the
operation of the instrument. To restore the drop it is provided with an arm
projecting into the case from its lower edge. A pivotted arin within the case rests
normally out of contact with this arm. The former is forced down upon the
latter, raising the drop, by a projecting head on one of the wings which strikes the
pivotted arm when the wings are raised to restore the segments. This projecting
head is preferably the eccentric head of a screw, so that by turning it an adjustment
can be made to bring the parts into the desired relative position.
Instead of one drop for the entire box, there may be a drop for each section
which would be released upon the completion of the operation of the particular
section. A multiplication of the parts before described would simply be
necessary.
It will be noticed that one of the features of the visual indicator heretofore
described is the use of gravity throughout, in the place of spiral or other springs.
The action of weights is much more reliable and uniform than that of springs; and
the weights have the advantage of permanency while springs ultimately give out.
The construction and arrangement of parts it will also be seen, are simple and
efficient, there being no fine adjustments or knife-edge stops; and in addition
there is no strain caused by giving the character wheels a continuous non-
intermittent movement and allowing them at times to gain considerable momentum
before being stopped.
The indicator forms an instrument that can be employed upon any line to receive
signals, and may be put to all the uses that visual indicators are adapted for, such as
burglar alarms, police and fire alarms, district telegraphs and for other purposes, or for
private lines, where codes of signals would be used to take the place of telephones,
dial or printing telegraphs.
The drop used in connection with the box makes the indicator especially
convenient and efficient for telephone exchange drops, hotel annunciators, and
for similar purposes, where it is desirable to show not only the person who is
calling but the person or service wanted.
For telephone exchanges there would preferably be one of the indicators provided
for each subscriber instead of the annunciator drop now universally used.
The subscriber would be provided with a suitable signal transmitter, arranged
for any number within the limits of the system. The subscriber can readily adjust
his transmitter and send the signal, and need not communicate his wants to the

page_text: central station over the telephone line. By having an indicator in addition to his
telephone, a subscriber when called up may be informed of the number of the person
who wants him.
For hotel-annunciators a number of room transmitters are preferably connected
with each indicator, either in multiple arc or series. The drop would indicate
the section or floor of the house, and the wheels would show the room and the
service.
The transmitter at each room would be arranged to always send a fixed signal
(the number of the room) while it would be adjustable for the different services,
any reasonable number of which could be secured.

page_text: The drawings illustrate the mechanism upon an enlarged scale, the size of the
parts being considerably reduced in practice, but the instrument may be of the same
size or even larger than shown in the drawings.
A is a suitable case, enclosing and protecting the parts. This case supports the
binding posts a a to which the line wires are attached. B is the operating electro-
magnet, enclosed within the case. Only one magnet is used to operate the
mechanism. It acts upon an armature carried by a lever C, which is retracted by
an adjustable spring b. To the armature lever C is pivotted a link c, which is
connected with an arm projecting from a rock shaft d. This arm is preferably one
of the pallet arms D carried by such rock shaft, of which there is one for each
section of the indicator. The arms D project upwardly from the rock shaft d and
carry pallets as shown on their upper ends, which pallets engage with the teeth of
vertically sliding escapement racks E, one of such escapement racks being provided
for each section of the indicator. Each of these racks E is slotted vertically and
provided on the edges of its slot with teeth e, the teeth on one side of the slot
alternating with those on the other side as will be well understood. Below the
lowermost tooth e, is a "safety tooth" e¹, on the escapement racks of all the sections,
which prevents the release of the locking device of the escapement rack, should the
rack of the preceding section be locked when the circuit is in other than its normal
condition. This "safety tooth" has no function on the first section, since there is
no preceding section.
Each escapement rack is provided on its rear edge with locking ratchet teeth f,
raking downwardly, such teeth being (at least) equal in number to all the
escapement teeth e, of the rack.
To the front of each escapement rack is attached, so as to work therewith, a cog
rack g, which preferably has sufficient weight to carry the rack downwardly with
rapidity and operate the character wheels F.
These character wheels are mounted upon short shafts, which carry pinions h,
engaging with the cog racks g. These escapement racks are guided in their vertical
movement by grooved posts G and vertical rods H, the rear of each rack sliding in
a groove in the face of a post G, while the arms that support the cog rack from
each escapement rack have holes through which the rod H passes.
In a slot in each post G is pivotted a locking and lifting book i, which is secured
to a rock shaft j, extending to the next succeeding section, if there is one, and there
carrying a supporting hook k. Each shaft ; has a weight secured eccentrically
thereto, which throws the hook i normally out of engagement with the teeth f of
the escapement rack with which it operates, and the hook normally under a
pin m on the side of the succeeding escapement rack.
All the escapement racks, except that of the first section, are provided with a
pin m engaging a hook k, while the shaft j which carries the locking and lifting
hook i of the last section, has no supporting hook k, since there is no succeeding
escapement rack to be held out of action while this last section is operating.
Each shaft is turned against the counteracting force of its weight 6, by a weight,
which is released when the escapement rack begins to drop, but whose movement is
retarded, so that the escapement rack can reach the limit of its movement and
come to a state of rest on the pallet before it will be locked and raised from
said pallet.
The weight in this mechanism is furnished by pivotted segments I, which have
fingers engaging with the backs of the hooks and forcing them in succession
into the teeth f locking and raising the escapement racks and releasing the
succeeding ones.
Each segment I has cog teeth engaging with a pinion on the shaft of a fan J
which retards the movement of the segment.
Each fan is somewhat heavier on one side than on the other, which heavier side
is brought uppermost when the parts are set for action, so that when the segment
is released the overbalanced fan will instantly start the movement.
Each segment has a pin n which engages with a hooked lever K pivoted to the

page_text: post G and overweighted at the end opposite the book so as to disengage the hook
from the pin n. The weighted end of the hooked lever is raised by the escapement
rack, but the dropping of the rack allows the weight of the hooked lever to
disengage the weighted segment. The hooked lever has however sufficient play to
allow the escapement rack to drop from its "safety tooth" e¹ to its lowermost
tooth e, without releasing the segment. Each lever K is limited in its movement
by a plate o, in order to prevent its displacement should the box containing the
mechanism be turned upside down in handling.
The joint operation of the parts thus far described is as follows, it being under-
stood that the character wheels F are provided with numbers, words or characters,
which are exhibited at an opening or openings L in the front of the box, and it
being further understood that the instrument is in electrical connection with a
suitable transmitter adapted to act with it.
Normally the escapement rack of the first section has its lowermost tooth e
resting on its pallet, while the escapement racks of the other sections are raised off
their pallets being supported by the hooks k.
The armature lever is moved by the action of the magnet and retracting spring,
and the vibrating pallet allows the escapement rack to fall a definite number of
teeth, depending upon the number of times the circuit is closed and opened, when
it will come to rest on the pallet. This movement will turn the character wheel
which has an intermittent movement similar to that of the rack, since it is moved
directly thereby as well as being controlled in its movement by the rack. The drop
of the escapement rack allows the weighted end of the hooked lever K to drop,
and the weighted segment is released, it being started by its own weight and that
of the over weighted fan J, and the movement being retarded by the fan. The
finger of the segment strikes the hook i and forces it into the teeth fraising the
escapement rack slightly, so that it will clear the pallet and allow it free movement.
The turning of the rock shaft j against weight withdraws the supporting hook /
from beneath the pin m of the next succeeding escapement rack and allows the
second rack to drop upon the pallet.
If the first escapement rack was locked, with the circuit normal (either opened or
closed according to the arrangement) the second rack will drop until its lowermost
tooth e rests on the pallet; otherwise the "safety tooth" e' will be caught by the
pallet, which will be supported until the normal condition of the circuit is restored,
when the pallet will go over to the lowermost tooth e and the section will be ready
to act. This operation continues through as many sections as are used (one or
more) the only difference being that the last section is simply locked without
releasing any other section. When the action has ceased, the complete signal will
appear at the opening or openings of the box.
To restore the parts to their normal position, the following devices are used. A
push button M is connected by a rod and arm with a rock shaft p which is provided
with a number of weighted wings N (one for each segment).
These wings engage with projections q on the segments I, and when the button M
is pushed inwardly are raised and restore the segments to an elevated position.
The rock shaft p also has loose arms Q, which engage with pins on the escape-
ment racks and raise such racks, the loose arms being lifted by pins on the
wings N. The arms O do not commence to raise the racks until after the wings N
have started the segments, so that the segments will reach their position before the
racks raise the hooked levers K, to lock such segments. At the same time that the
segments are raised, the shafts j are released and their weights withdraw the
hooks from the teeth f and move the hooks k under the pins m. The weight of
the wings N and arms O returns the restoring devices to their normal position,
leaving the parts ready for action.
Instead of having a cog rack g on the front of each escapement, and moving a
wheel carrying the characters, numbers, letters or words, the characters may be on
a plate or strip F' carried directly by the escapement racks as shown in Figure 8.
This form may be used although the wheels are preferred, since much larger

page_text: characters can be used in the same space with the wheels than with the plates or
strips.
The instrument herein before described is a complete indicator, adapted for all
uses to which such instruments may be applied.
For some purposes, the opening (or openings) L in the front of the box, is closed
by a pivotted or sliding shutter or drop P, which is arranged to disclose the opening
and to itself display or to disclose a number, word or character when dropped
down. The drop has a hook 8, at its upper edge, projecting through an opening in
the box, when the drop is raised, and engaging a pivotted locking arm Q within
the case.
This arm Q drops by its own weight into engagement with the hook s
locking the drop.
It is raised to release the drop by an arm t on the shaft j of the last section.
The arm t strikes the arm at the same tine that the escapement rack of the
last section is locked, and the drop is thus allowed to fall only at the completion of
the operation of the instrument. To restore the drop, it is provided with an arm u
projecting into the case from its lower edge. A pivotted arm R within the case
rests normally out of contact with the arm u. Arm R is forced down upon arm u,
raising the drop, by a projecting head von one of the wings N, which strikes the
arm R when the wings are raised to restore the segments. The head v is preferably
the eccentric head of a screw, so that by turning it an adjustment can be made to
bring the parts into the desired relative relation.
Instead of one drop for the entire box, there may be a drop for each section,
which would be released upon the completion of the operation of the particular
section. A multiplication of the parts before described would simply be necessary.
It will be noticed that one of the features of the visual indicator, heretofore
described, is the use of gravity throughout, in the place of spiral or other springs
The action of weights is much more reliable and uniform than that of springs; and
the weights have the advantage of permanency while springs ultimately give out.
The construction and arrangement of parts, it will also be seen are simple and
efficient, there being no fine adjustments or knife edge stops; and, in addition,
there is no strain caused by giving the character wheels a continuous non-inter-
mittent movement and allowing them at times to gain considerable momentum
before being stopped.
The indicator forms an instrument that can be employed upon any line to
receive signals, and may be put to all the uses that visual indicators are adapted
for such as burglar alarms, police and fire alarms, district telegraphs & or for
private lines where codes of signals would be used to take the place of telephones,
dial or printing telegraphs.
The drop used in connection with the box makes the indicator especially-
convenient and efficient for telephone exchange drops, hotel annunciators, and for
similar purposes, where it is desirable to show not only the person who is calling
but the person or service wanted. For telephone exchanges, there would preferably
be one of the indicators provided for each subscriber, instead of the annunciator
drop now universally used.
The subscriber would be provided with a suitable signal transmitter arranged
for any number within the limits of the system. The subscriber can readily adjust
his transmitter and send the signal, and need not communicate his wants to the
central station over the telephone line. By having an indicator in addition to his
telephone, a subscriber when called up may be informed of the number of the
person who wants him.
For hotel annunciators, a number of room transmitters are preferably connected
with each indicator either in multiple arc or series.
The drop would indicate the section or floor of the house, and the wheels would
show the room and the service.
The transmitter at each room would be arranged to always send a fixed signal
(the number of the room) while it would be adjustable for the different services,
any reasonable number of which could be secured.

page_text: Having thus described the nature of the said Invention and the mode in
which the same is carried into effect I would have it understood that what I
claim is―
First. In an electrical visual indicator, the combination with an escapement
rack controlled by a pallet vibrated electro-magnetically, of a character wheel,
operated and controlled directly by such escapement rack, substantially as herein
described.
Second. In an electrical visual indicator the combination with a vertically
sliding escapement rack, controlled by a pallet vibrated electro-magnetically, of a
cog rack carried by such escapement rack, a character wheel and a pinion
engaging the cog rack and turning the character wheel substantially as herein
described.
Third. In an electrical visual indicator, the combination with an escapement
rack, controlled by a pallet vibrated electro-magnetically, of a character wheel and
means independent of the character wheel, for locking such escapement rack directly
at any point of its movement substantially as herein described.
Fourth. In an electrical visual indicator, the combination with an escapement
rack, controlled by a pallet vibrated electro-magnetically, of a locking device,
engaging such rack directly and having a retarded movement substantially as
herein described.
Fifth. In an electrical visual indicator, the combination with an escapement
rack, controlled by a pallet vibrated electro-magnetically, and having a set of
locking teeth, of a locking hook forced into the teeth of the rack by a weight
having a retarded movement, and a locking device for the weight, released by the
drop of the escapement rack substantially as herein described.
Sixth. In an electrical visual indicator, the combination with an electro magnetic
escapement, having locking teeth, of a locking hook, a pivotted segment forcing
such hook into the teeth of the escapement rack, and a fan for retarding the
movement of the segment, substantially as herein described.
Seventh. In an electrical visual indicator, the combination with a vertically
sliding escapement rack, controlled by a pallet vibrated electro-magnetically, and
having a set of locking teeth, of a pivotted hook, forced into such teeth when the
rack has finished its movement locking such rack and raising it off the pallet,
substantially as herein described.
Eighth. In an electrical visual indicator, the combination with an escapement
rack, controlled by a pallet vibrated electro-magnetically and having a set of
locking teeth, of a pivotted locking hook, a weight keeping such hook normally
out of engagement with the locking teeth of the rack, and a weight having a
retarded movement, such latter weight being released by the movement of the
escapement rack and forcing said locking hook into the teeth of the rack,
substantially as herein described.
Ninth. In an electrical visual indicator, the combination with an escapement
rack of a locking hook withdrawn normally, a weighted segment, forcing such
hook into action, a fan for retarding the movement of the segment, and a
pivotted hooked lever locking the segment and raised by the rack, the dropping
of such rack releasing the lever and unlocking the segment substantially as herein
described.
Tenth. In an electrical visual indicator the combination with two or more
escapement racks, of character wheels operated and controlled directly by such
racks, vibrating pallets controlling the racks and operated by one electro magnet,
means for supporting the second and succeeding racks out of operative connection
with the pallets, and means for locking each rack directly at the completion of its
movement and raising it off the pallet, releasing at the same time the next
succeeding escapement rack, substantially as herein described.
Eleventh. In an electrical visual indicator, the combination with two escape-
ment racks, controlled by pallets vibrated electro magnetically, of a rock shaft
provided with a locking hook and a supporting hook, thrown in opposite directions.

page_text: by the movement of the shaft and acting directly upon the racks, the locking hook
being held normally out of action and the supporting hook normally in action,
and a part, having a retarded movement, for turning such shaft and throwing the
locking hook into action and the supporting hook out of action, such part being
released by the movement of the first of the two escapement racks, substantially as
herein described.
Twelfth. In an electrical visual indicator, the combination with two escapement
racks, each having locking teeth and one (or each) having a supporting pin or
projection, such racks being controlled by pallets vibrated electro inagnetically, of
a weighted rock shaft provided with oppositely moving locking hook and sup-
porting hook, a weighted segment for turning such shaft against its normal tendency,
a fan retarding the movement of such segment, and a locking device released by
the movement of the first rack for holding such segment, substantially as herein
described.
Thirteenth. In an electrical visual indicator the combination with the escape-
ment racks, vibrating pallets and locking devices, of the rock shaft and the arms for
raising the racks, substantially as herein described.
Fourteenth. In an electrical visual indicator, the combination with the
escapement racks, the vibrating pallets, the weighted segment and the locking
devices, of the rock shaft having wings and arins raising such segments and racks
in succession substantially as herein described.
Fifteenth. The combination with an electro magnetically operated visual
indicator, of an annunciator drop or drops, whereby the person calling and the
person or service called for can be shown, substantially as herein described.
Sixteenth. The combination with an electro magnetically operated visual
indicator, of a drop or drops released by the action of such indicator mechanism
substantially as herein described.
Seventeenth. The combination with an electrical visual indicator, of a drop or
drops released by the action of such indicator and a restoring device, connected
with and operated by the restoring device of the indicator mechanism substantially
as herein described.
Eighteenth. In an electrical visual indicator, the combination with an electro
magnetic escapement or escapements, of a pivotted drop, a locking arm, and a
releasing arm, operated by the movement of the locking device of an escapement,
substantially as herein described.
Nineteenth. In an electrical visual indicator, the combination with an electro-
magnetic escapement or escapements, of a pivotted drop having an arm projecting
within the indicator case, a pivotted lever for moving such arm, and a projection
from a moving part of the indicator restoring device for operating such pivotted
lever, substantially as herein described.
Twentieth. In an electrical visual indicator, the combination with an electro
magnetic escapement or escapements, the locking, supporting and releasing devices
and the character wheels, of a pivotted drop, and a restoring device, resetting both
the indicator mechanism and the drop simultaneously, and an adjustable connection
between the drop and the restoring device for giving the parts the desired relation
substantially as herein described.
In witness whereof I the said Benjamin Joseph Barnard Mills have hereunto
set my hand and seal this sixth day of March in the year of our Lord
One thousand eight hundred and eighty three.
B. J. B. MILLS (L.S.)