IMPROVEMENTS IN APPARATUS FOR " PRODUCING AND REGULATING ELECTRIC CURRENTS FOR THE PRODUCTION OF THE ELECTRIC LIGHT AND IN THE LAMPS FITTINGS AND APPARATUS EMPLOYED THEREWITH, PART OF SUCH APPARATUS BEING APPLICABLE TO OTHER PURPOSES."
Year: 1882

page_text: LETTERS PATENT to Alfred Richard Sennett of Worthing in the County, of
Sussex Engineer for an Invention of IMPROVEMENTS IN APPARATUS FOR
"
PRODUCING AND REGULATING ELECTRIC CURRENTS FOR THE PRODUCTION
OF THE ELECTRIC LIGHT AND IN THE LAMPS FITTINGS AND APPARATUS
EMPLOYED THEREWITH, PART OF SUCH APPARATUS BEING APPLICABLE TO
OTHER PURPOSES."
:
PROVISIONAL SPECIFICATION left by the said Alfred Richard Sennett at
the Office of the Commissioners of Patents on the 20th September 1882.
ALFRED RICHARD SENNETT of Worthing in the County of Sussex Engineer
"IMPROVEMENTS IN APPARATUS FOR PRODUCING AND REGULATING ELECTRIC
CURRENTS FOR THE PRODUCTION OF THE ELECTRIC LIGHT AND IN THE LAMPS
FITTINGS AND APPARATUS EMPLOYED THEREWITH PART OF SUCH APPARATUS
BEING APPLICABLE TO OTHER PURPOSES."
-
My Invention relates to Apparatus for the conversion of Mechanical into
Electrical Energy the methods of regulating the same more particularly for the
production of the Electric Light and to the Lamps fittings and Apparatus employed
in its application to various purposes.
12
My improved Apparatus for the production of Electric Currents is of the
following description,
The construction of the armature will be understood by comparison with the
well known Pacinotti ring. armature. In this a ring of. soft iron furnished with
indentations upon its periphery was wound with an insulated conductor until these
were filled the intervening projections. serving. to divide the coil into Sections..
There are several defects in this which my improved apparatus is designed to
overcome, the objects being 1st to reduce the length of inefficient conductor. upon.
the ring-2ndly to provide means for firmly attaching the ring to the shaft of the
machine and for binding the conductor firmly to the ring that it may not fly out
under the action of centrifugal force, in order that the conductor may be brought

page_text: in very close proximity to the poles of the field magnets 3rdly To give to the ring
such a form (in section) that the conductor shall only be in contact with those
portions which are indued with a polarity tending to produce a current in the
required direction, and also to prevent the circulation of the so called Foucault
currents, 5thly to diminish induction in parts of the Sections of the Conductor and
to provide a means for the escape of heat.
For these purposes I construct the ring in the form of a hollow box (in section
at right angles to its plane) preferably of wrought or malleable cast iron, the sides
of which are continuous with one exception in which a space is left. This can be
rigidly attached to the shaft of the Machine. To increase the surface of the ring
I form in it grooves or corrugations. When wire is wound upon the ring I draw
it into these indentations by means of bands of a diamagnetic substance, but in all
ordinary cases I prefer to use sheets of metal cut or punched out to the form of the
ring and slipped thereon. A number of these plates being connected sometimes in
series sometimes in multiple to form sections The plates are kept apart by the
insertion of pieces of a suitable insulating material. This form and method of
affixing the conductor reduces the induction taking place between different members
of the Sections and offers great facility for the dissipation of the heat generated
both in the Conductor and the ring. The ring may be built up of any number
of segments the projections being formed of separate pieces and so shaped as to
act as fish plates. This method of constructing the Armature allows of its being of
any dimensions (its efficiency not being decreased by increase in diameter as is the
case with some Armatures) and it has the following advantages 1st that a high
e. m. f, (with low internal resistance) may be obtained with a moderate speed of
the shaft, and 2ndly that its momentum causes it to be less affected by momentary
alterations either in the resistance or counter c. m. f. of the work circuit or of the
velocity of the motor by which it is driven (such as is caused by want of promptness
on the part of the governor, slipping of the belt &c) than are Armatures of smaller
diameter. The field Magnets are constructed in a manner analogous to that
employed in the armature. The cores (of which there may be several) are hollow
a space being left in one side and the conductor is applied in a similar manner.
The pole pieces of the field magnets are so shaped as to enter the corrugations
of the armature, To concentrate or condense the magnetic field I enclose the
field magnets in iron sheathing. Permanent Magnets may be employed when
desirable.
My Apparatus for regulating the Electric energy either by governing the strength
of the Current (or the e. m. f. of the same) consists essentially of an epicyclic train
of wheels the intermediary wheel (or wheels) of which is made to effect the
regulation by more or less work being thrown on the train according to variations
in the Electrical conditions of the work circuit. This regulation may be effected
in various ways as for example, varying resistances, increasing or diminishing the
number of Elements if batteries or accumulators are employed shunting portions of
the current in other directions &c. &c.
For the purposes of Electric lighting however I prefer to employ the following
system. One or more generators the field magnets of which are excited by another
generator (which may be either Magneto or dynamo-Electric) are employed during
the time when no use is being made of the work circuit to charge accumulators.
During this operation the Conductor upon the Armatures of the excited generators,
is coupled in parallel. The accumulators are divided into two groups which for
convenience may be called main and auxiliary. The main group is charged directly
by the excited generator. The auxiliary group is placed in a shunt or derived
circuit between the exciting and excited generators. This system is provided with
a governor and so arranged that the intensity of the magnetic field of the excited
Machine and consequently the Electrical energy developed by it is varied in
accordance with the demands made upon it by the main group of accumulators.
Such variation being caused by the shunting of more or less current into the
auxiliary group of Accumulators. These conditions obtain until the main group

page_text: is completely charged when the whole of the current will be shunted through the
auxiliary group. In doing so it may if desired be made to stop the current, or
the Machine or the motor &c. When it is desired to make use of the work
circuit or circuits the latter are attached to the accumulators and excited generators
the conductor upon the armatures being now coupled in series. The regulation
(according to the requirements of the work circuit) is effected by a precisely
similar method to that employed in charging the accumulators. At convenient
intervals the small group of accumulators is replaced by another taken from the
main group (after discharge) and is itself added to the main group. It is of course
unnecessary to remove the Accumulators themselves the substitution being more
conveniently performed by turning suitable switches. In order to effect this
regulation I cause the intermediary wheel or wheels of the Epicyclic train afore
mentioned to make a compound wheel traverse a kind of double tramway on which
are arranged contact pieces. If the number of contact pieces is not great the
tramway is in the form of a circle, in which case the compound wheel maintains
a certain position on its shaft, if however the number is very great the tramway
may very conveniently be laid in the form of a volute in which case the compound
wheel is free to move longitudinally upon the shaft so that it may take up a
position (at any distance from the centre of motion) dependent on the position
of the wheel upon the volute. The wheel is made in two parts electrically insulated
from each other and carries a resistance coil the two ends of which are connected
to the two distinct parts of the wheel. The contact pieces upon the periphery
of the wheel and upon the tramway are so arranged that the flow of the current
is not interrupted upon contact being broken with any of the contact pieces but
is caused to pass through the resistance coil. The train of wheels may be driven
by any suitable means.
The object in employing the epicyclic train is to obtain' great promptness in
action by drawing upon the Energy stored up by the rapidly rotating parts, and
to further promote promptness I prefer to use a current from a separate source for
exciting the Electro Magnets or soleroids employed for throwing the work on and
removing it from the train and to put them into circuit by means of a delicate
arrangement analagous to a polarized relay used in Telegraphy. Where however
the variations in the work circuit are not considerable the compound wheel and
tramway arrangement may be actuated directly. In cases where currents of but
moderate strength are employed I make use of another form of Apparatus. This
consists of a tube constructed either wholly or partially of an insulating material'
in the sides of which the contact pieces are inserted and the contacts are made
and broken by the movement of a Conductor in its interior. The ends of the said
tube are enlarged or connected to larger vessels which are provided with flexible
diaphragms. These diaphragms are moved Electro-magnetically by variations in
the work circuit and their movement is transmitted (much amplified) to the
moveable conductor afore mentioned. In order to prevent the Current being
interrupted the Contact pieces are pointed and bent so as to lie parallel with the
axis of the tube and the moveable conductor is made of such a length that contact
is made with the succeeding contact piece before it has been broken with the
preceding one the pointed form of the contact piece offering a gradually increasing
resistance until the Contact is entirely broken The moveable conductor is always
kept in contact with the work circuit; it may very conveniently be formed by a
small quantity of Mercury. When Electric Accumulators are employed it is
necessary in order to attain a high efficiency to arrange 1stly for automatically
regulating the current so that too strong a current may not pass and 2ndly to
provide means whereby the circuit may be broken when the e. m. f. of the
accumulator exceeds that of the generator. For this purpose I employ a regulator
of the following description. A permanent Magnet is delicately suspended
preferably by means of a spring or by being balanced similarly to an ordinary
balance and is influenced by an Electro Magnet or Solenoid placed in a shunt
circuit. Jointed to the permanent Magnet or the train but capable of independent
:

page_text: motion is a small arm or lever which completes or breaks the main circuit
according to the movements of the Magnet or beam. A stop is so arranged in
relation to the small lever that sufficient freedom of motion is allowed to it to
complete or break the circuit but upon the Motion being continued (caused
by the passage of too powerful a current) the stop engages with the lever and
causes it to break contact-In order to increase the sensibility of the apparatus
to any sudden variation or reversal of the current I prefer to allow the main
current also to circulate in the Electro magnet or solenoid after contact has been
established.
In the distribution of Electric energy to various consumers for Electric lighting
or for the transmission of power (as is at present accomplished by Coal gas), it is
necessary to provide means of registration and this in a manner as devoid of
technicality as possible. For this purpose suppress all measurements of current
passing, e. m. f. of the current &c. &c. and cause the alterations in the electrical
conditions of the circuit as for instance variations in resistance caused by the
ignition, extinction, or employment of more or less Lamps, or the variations in the
counter e. m. f. caused by the starting stopping or employment of more or less
motors to record by suitable apparatus the number of Lamps or motors in action
and to give the result in Lamp-hours and horse-power hours respectively. To this
end I construct an apparatus one portion of which always moves with a constant
velocity and I cause the alterations in the Electrical conditions of the circuit to
alter the ratio which the velocity of the registering apparatus bears to the constant
velocity of the other portion of the apparatus.
The apparatus may be driven by any suitable means but in most cases I prefer
to employ a miniature Electro-motor the speed of which is controlled by a
conical pendulum driven by an epicyclic governor analagous to that hereinbefore
explained which controls the current passing in the Electro-motor. In this case
however it is preferable to form the tramway afore mentioned of a continuous
high resistance conductor.
For the illumination of small spaces I prefer to employ Lamps constructed as
described in the Specification of a Patent granted unto me bearing date the 3rd day
of December 1881 N° 5286, with the following additions. These additions consist
of cheap and simple methods of 1st connecting the incandescing conductor to the
conducting wire or wires, 2nd forming the joint between Lamps Chandeliers brackets
and other fittings in such a manner that they may be instantly attached or
detached by unskilled hands. 3rdly Making and preserving contact in the moveable
joints of the fittings themselves and 4thly in a simple tap or switch for putting the
Lamp in or out of circuit.
My improved method of connecting the incandescing conductor to the con-
ducting wire consists in placing the enlargements (referred to in the Specification
afore mentioned) which may be solid or in two halves into a metallic socket.
(preferably of brass split in one or more places to secure elasticity.) Through
this socket or the bottom of the same I drill a hole or holes at right angles to the
plane of its axis, and also one or more (generally smaller in diameter) in a
direction parallel to its axis so as to run into the former.
The ends of the conducting wires (after having been sealed into the diaphragm
referred to in the afore mentioned Specification and which I prefer to make quite
flat) are passed up the smaller holes into the larger and metallic pins are inserted
in the latter. These pins by forcing the conducting wires from their original
positions make good contact and firmly key the socket and with it the incandescing
conductor to the conducting wire.
Where the number of the conducting wires is great I employ a separate
cylindrical piece of metal provided with holes drilled parallel to its axis and having
passed the wires through these I bend them over and screw the upper part of the
socket down upon them.
My improved method of attaching the Lamp to the fittings is as follows:
The Electrades of the Lamn are attached contact plates each of which is

page_text: provided with a corrugation or deep indentation. These plates together with the.
lower part of the Lamp are placed in a mould and are temporarily held' to two
projections on the inner side thereof such projections being slightly narrower than*
the plates themselves. Into this mould is cast a suitable insulating substance.. By
this means the contact pieces are firmly attached to an insulating stem and this
latter is rigidly attached to the Lamp. The conducting wires terminate in two
insulated springs, the extremities of which are moulded to the form of the corru-
gations or indentations of the contact plates. These springs are placed within (but
insulated from) a socket into which the insulating stem afore mentioned just fits.
To insure the contact pieces being always introduced exactly opposite the springs
the socket is provided with two tongues or projections which slide in the inden-
tations formed by the projecting pieces in the mould afore mentioned. To attach
the Lamp to the conducting Wires and the Chandelier or other fitting it' is only
necessary to push it into the socket, when the convex projections of the Springs
falling into the concave depressions of the contact plates make good contact and
retain the Lamp firmly in position. To detach the Lamp it is only necessary to pull
it with sufficient force to cause the springs to yield and thus extricate their
projections from the indentations of the contact plates when the Lamp will become
detached.
It will be observed that the whole of the Contacts are within the socket which
may or may not be of an insulating material consequently the Lamps may be
removed and replaced whilst the current is on, it being impossible even by
carelessness to divert the current.
1
This method of making connection is applicable to all ordinary junctions
especially where it is desirable to be able to couple up and uncouple expeditiously;
as for example, for making connection between Railway Carriages One great
advantage which this method of connection possesses over ordinary couplings is
that it is almost impossible to short circuit the Current when the connection is
asunder, with the female end it is quite impossible in ordinary use and with the
male end it is almost impossible, but may be made quite so, by simply providing it
with a socket slightly larger than that of the female.
The connections in the moveable and swinging joints of the fittings are made in a
similar manner except that the springs are replaced by rings. The ends of the
arms of the fittings which are to be connected by a swinging or universal joint are
formed into hollow chambers provided with apertures for the introduction of the
insulating substance and instead of being connected by the tapering plug used in
gas fittings an ordinary parallel pivot is employed.
To form it two concentric rings connected to the conducting wires are placed in
position with the pin as centre. The bottom of the chamber is closed by a smooth.
surface and the insulating substance poured in as before explained. When the
latter is cool the rings are both rigidly connected and insulated. The companion.
end of the fitting is treated in like manner and when the joint is put together the
four rings slide on one another and preserve contact in whichever direction the joint
may be turned.
The taps or switches are of the following description. There are two requirements
which a tap or switch should fulfil-1 to make and preserve a good contact and
2ndly to reduce as much as possible the amount of sparking when contact is broken.
For currents of moderate strength such as are employed in incandescent Electric
lighting the sparking will be sufficiently reduced if the contact be disestablished
very quickly. For this purpose switches are generally made with rigid contact
pieces and the movement of the moveable portion or switching piece is accelerated
by the employment of a spring generally coiled around the spindle carrying the
switching piece, stops being properly placed to limit the movement of the latter.'
My improvement consists in forming the contacts of springs and suppressing the use
of the accelerating spring or springs by giving to the contact spring or springs such
a form that it or they will of itself or themselves urge the switching piece forward,
whilst to obviate the use of stops I form in one of the contact springs an indentation'

page_text: into which a portion of the switching piece falls and is thus firmly held in position.
Two advantages are obtained by this device 1st the tap or switch is much simplified
and 2nd the contact is always good as the pressure of the springs keeps the surfaces
firmly in contact and the friction between the springs and the switching piece
ensures the contact surfaces being always kept bright and clean. For currents of
greater strength however this process of quickly breaking contact is insufficient to
prevent the burning of both the contact and switching pieces-Switches for
powerful currents are therefore generally provided with massive contact pieces so
disposed as to be easily re-surfaced or filed true from time to time and the switching
piece is so arranged that it may be filed and set up to the contact pieces as they
become thinner. In addition to this objection arising from the inconvenience and
expense of having repeatedly to make good the contact surfaces there is a still more
important one, for it is found that upon each act of breaking contact a small portion
of the surfaces is brought to a molten condition, the surfaces being thereby
roughened and therefore upon connection being re-established these portions prevent
the surfaces bearing properly on each other, consequently the Electrical contact is
not good and a resistance is offered to the passage of the current. My improve-
ment consists in the employment of contact pieces 80 constructed and arranged that
the current is first diverted through a path of very small resistance and this
resistance is afterwards increased until it becomes very great when contact is
disestablished. By this means the strength of the current is so far reduced that
the spark formed on breaking contact is harmless and does not take place upon the
contact piece at all. One method I employ to effect this consists in forming the
contacts of a number of pieces insulated from one another each provided with a
resistance, and arranging contact plates on the switching piece in such a manner
that upon its being turned the resistances are 1st coupled in parallel 2nd gradually
reduced in number in parallel and 3rdly coupled in series.
For ordinary purposes of illumination the incandescent Lamps described in the
Specification afore mentioned may be used either quite exposed or enclosed in any
suitable shade or globe. Where however they are to be employed in or in the
vicinity of very inflammable or explosive substances or explosive mixtures of gas
and air, as for example in Coal mining, I prefer to enclose them in an outer globe or
Jantern furnished with the following safety appliance.
My improved automatic safety appliance consists of an automatic switch or
contact breaker and method of actuating it, whereby the passage of the current is
immediately arrested (preferably at some distance from the Lamp as for example in
a suitable wall box) upon any portion of the outer globe or lantern becoming
damaged or broken, and also where desirable to effect the same upon the failure of
the incandescing Conductor. To this end I enclose the Lamp in an outer case or
lantern (which may be wholly or partially of glass.) This outer casing is either
evacuated or filled with liquid under slight pressure. The conducting wires are
brought to the Lamp and connected thereto as herein before explained. With this
addition that one of them is also connected to a contact piece of a Switch or contact
maker actuated by the pressure of the atmosphere or of the liquid contained in
the outer casing. The remaining contact piece of the switch or contact maker is in
connection with an Electro Magnet or solenoid actuating a switch or contact
breaker placed in any convenient position and at any distance from the Lamp (and
preferably working in a liquid insulator if placed in the Mine)
The action of the appliance is as follows; while all is working well and under
normal conditions the contact maker in the lantern remains open and the current
flows through the lamp, should however the lantern become damaged (be it only a
crack in the glass) the atmospheric pressure is admitted (if the outer casing has
been evacuated) or the pressure removed (if liquid be employed). The effect of
this is to close the contact maker in the Lantern whereby the current is sent
through the coils of the Electro-Magnet afore mentioned and the Current arrested by
the contact breaker in the wall box (or other position) being opened. It will be
observed that in this operation no contact is broken in or near the lamp and

page_text: consequently no spark can pass except in the wall box where it can do no harm.
The lantern may now be opened and a new lamp inserted without danger of short
circuiting the current and thereby producing sparks and no current can be sent
through the lamp until the lantern has been properly put together and the vacuum
(or liquid) restored. If required the switch in the wall box may be actuated when
the incandescing conductor of the lamp fails, by providing the contact breaker (in
the wall box) with a high resistance magnet (placed in divided circuit with the
lamp) or both high and low resistance coils may be wound upon the same magnetic
core. This however is not necessary for immediately an attempt is made to open
the lantern the current is arrested as if the same had been damaged or broken.
For the illumination of large spaces I prefer to employ Lamps giving their light
by means of the electric arc.
The chief requirements to be fulfilled in arc lamps for the production of steady
lights are, that they should be provided with suitable but simple mechanism for
maintaining a constant strength of current if one only is to be used in circuit or to
maintain a constant difference of potentials at the two sides of the arc if several
are to be worked in series-that they should be capable of imparting a very delicate
feed to the Carbons at very short intervals of time that the moment of inertia of
the governing parts should be very small so that the mechanism may promptly
respond to any slight variations in the required conditions and that they should be
able to instantaneously bring the carbons in contact in the event of a cessation of
the current such as that for example which frequently takes place through the
dropping off of a small piece of one of the carbon electrodes. It is therefore
necessary 1st that the electrical arrangements be such that the slightest alterations
in current strength in the one case or of the resistance of the arc in the other be
caused to act on the feed mechanism and 2ndly that the moment of inertia of both
this governing device and of the whole mechanism be very small.
In order to obtain delicacy in the feed all Lamps hitherto constructed have been
provided with long trains of wheelwork the objects being 1st to reduce as
much as possible the work done by the governing device and 2ndly to reduce a
comparatively course feed given by the governing device to a very fine one of the
carbons themselves. The feed is generally governed by the movement of heavy
armatures or solenoid cores or plungers. The objection to this method of imparting
a delicate feed is that the moment of inertia of both the train of wheels and the
governing device is great and consequently the delicacy of feed is obtained at the
expense of promptness. My improved regulating mechanism for Electric Lamps and
method of governing the movement of the same consists 1stly in substituting an
epicyclic for the ordinary train and 2ndly in substituting for armatures or solenoid cores
a very light and delicately suspended or balanced electro-magnet or solenoid working
under the influence of one or more stationary electro-magnets or solenoids. The
said moveable electro-magnet or solenoid may form part of the main circuit or a
derived circuit of it when the action of the lamp is not required to be differential,
or it may form part of a divided circuit excluding the arc if the action of the lamp
is required to be differential. By the employment of the Epicyclic train I am
enabled to obtain any degree of delicacy in the feed with a very few small wheels
(in any case the number need not exceed four). Whilst by the employment of the
small electro magnet or solenoid moveable in relation to the controlling magnets or
solenoids I obtain great sensibility.
In cases where it is necessary to exhibit the light for periods of time longer
than that required for the consumption of the carbon rods, multiple carbon lamps
are employed. It has been the practice hitherto to allow the carbons not in use to
be in contact. The objection to this plan is that in certain positions the light is
occulted and shadows are cast by the rods not in use, I obviate this difficulty by
keeping the rods (not in use) apart until the ones in use are consumed when the
current allows them to come together and when desirable (as when more than two
pairs are employed) I cause the approach of the new carbons to separate the old
The high efficiency of the electric arc (as compared with other systems of
ones.

page_text: illumination) is due to its power of concentrating a large amount of heat energy
into a small space. In order to further increase its efficiency by diminishing the
loss of heat I sometimes place around one or both of the electrodes a ring or block
of véry refractory material having a hole in it just large enough to allow of the
passage of the carbon. In cases where the steadiness of the light is of no great.
moment the 'feed of the carbons may be regulated by these blocks of refractory
material in which case the feed mechanism is not required, it being only necessary
to provide for the formation of the Arc. I am aware that electric arc lamps have
been constructed in which both carbons have been supported in a block of
refractory material, but as the insulating capability of an insulator diminishes
inversely with the temperature upon the block becoming hot and sometimes
incandescent great loss of energy takes place. Such however is not the case when
the insulator does not connect the carbons as in my arrangement.
In ordinary illumination it is generally required to uniformly illuminate a certain
ground or floor area, for which purpose all rays emitted by the Arc having an
upward or horizontal direction are useless. The distribution of light from the arc
produced by unidirectional currents is far from uniform.
The greater portion of the light is emitted by the crater formed in the positive
carbon which would illuminate a horizontal plane with tolerable uniformity were
it not that the negative carbon greatly obscures the light and renders the central
portion of the horizontal plane far less intensely illuminated than segmental
portions more remote from the centre, the greater the elevation of the light the
more pronounced is this defect. In order to obviate this objection and also to
utilize the rays proceeding in and above a horizontal plane passing through the
Arc I place around the arc total reflection prisms having angles such that rays
originally having an upward and horizontal direction are turned downwards and
made to illuminate' the otherwise less intensely illuminated portion afore mentioned.
"In order to reduce the cost of manufacture of prisms for use with powerful arcs
(where it is necessary to keep them a considerable distance from the arc in order
to avoid fracture from the heat radiated) I form them hollow (preferably of sheet
glass) and fill them with liquid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alfred Richard Sennett in the Great Seal Patent Office on the
20th March 1883.
ALFRED RICHARD SENNETT of Worthing in the County of Sussex, Engineer,
"IMPROVEMENTS IN APPARATUS FOR PRODUCING AND REGULATING ELECTRIC
CURRENTS, FOR THE PRODUCTION OF THE ELECTRIC LIGHT, AND IN THE LAMPS,
FITTINGS AND APPARATUS EMPLOYED THEREWITH, PART OF SUCH APPARATUS
BEING APPLICABLE TO OTHER PURPOSES."
My invention relates to apparatus for the conversion of mechanical into electrical
energy, the methods of regulating the same, more particularly for the production of
the electric light and to the lamps, fittings and apparatus employed in its
application to various purposes. My improved apparatus for the production of
electric currents is of the following description. The construction of the armature
will be understood by comparison with the well known Pacinotti ring armature.
In this a ring of soft iron furnished with indentations upon its periphery is
wound with an insulated conductor until these are filled, the intervening pro-
jections serving to divide the coil into sections. There are several defects in this
which my improved apparatus is designed to overcome the objects being (a) to
reduce the length of inefficient conductor upon the ring (b) to provide means for
firmly attaching the ring to the shaft of the machine and for binding the conductor
firmly to the ring, (that it may not fly out under the action of centrifugal
force) in order that the Conductor may be brought in very close proximity to the
poles of the field magnets, (c) to give to the ring such a form (in section) that. the
conductor shall only be in contact with those portions which are indued with a
polarity tending to produce a current in the required direction, and also to prevent
the circulation of the so called Foucault currents, (d) to diminish induction in the
sections of the conductor and to provide a means for the escape of heat. For these
purposes I construct the ring in the form of a hollow box (in section at right
angles to its plane) the sides of which are continuous with one exception in which
a space is left. This can be rigidly attached to the shaft of the Machine. To
increase the surface of the ring I form in it grooves or corrugations. When wire is
wound upon the ring I draw it into these indentations by means of bands of a
diamagnetic substance, but in cases where the armature is of large dimensions I
prefer to use sheets of metal cut or punched out to the form of the ring and slipped
thereon, (being slit at one point to prevent continuity) or bands or strips of metal
bent to the form of the ring, a number of these plates, bars or strips being
connected sometimes in series and sometimes in multiple to form sections. The
plates &, are generally kept apart by the insertion of suitable insulating material
or by being so held that a space is left between each. This method of constructing
the armature allows of its being of any dimensions (its efficiency not being
decreased by increase in diameter as is the case with some armatures) and it has
the following advantages (a) that a high e. m. f. (with low internal resistance) may
be obtained with a moderate speed of the shaft, and (b) that its momentum (when
of large size) causes it to be less affected by momentary alterations either in the
resistance or counter e. m. f. of the circuit or of the velocity of the motor by which
it is driven than are armatures of smaller diameter. The Field magnets are
constructed in a manner analogous to that employed in the armature. The cores
(of which there may be several) are hollow a space being left in one side and the
conductor is applied in a similar manner. The pole pieces of the Field magnets
are so shaped as to enter the corrugations of the armature. To concentrate or

page_text: condense the magnetic field I enclose the field magnets in iron sheathing.
Permanent magnets may be employed when desirable. Figure I sheet I shews
a method of carrying this into effect. The upper view shews an elevation
of the armature (without the conductor) and the lower view a section on
the line a, a, all a¹, The ring may be built up of any number of segments (the
one shown having four) the several segments being united by being bolted to the
parts b, b, b, b, & which are so shaped as to act as fish plates. The portions of
dia-magnetic material are shewn by the section lines having a diagonal direction,
whilst the para-magnetic portions are shown by the vertical section lines the pole
piece being shown by the broken section lining. The conductor is represented by
c. c. c. &. In machines for the production of currents alternating in direction and
also in those for producing uni-directional currents when of large dimensions. I
prefer to construct the armature wholly of dia-magnetic material. One objection to
the employment of armatures containing no para-magnetic material has hitherto
been that the lines of force of the field magnets are spread out over so large an
area that a great number of them are useless and that the space through which
the moving conductor passes forms but a small portion of the whole magnetic field
and is consequently comparatively weak. To condense or concentrate the field and
thereby intensify it two methods have been adopted (a) to employ iron in the
'armature and (b) to place within the armature poles of opposite sign to that of the
field magnets. My method of effecting this concentration is to enclose the field
magnets in iron sheathing as herein before mentioned but when convenient I also
prefer to employ internal field magnets. Figure 2 Sheet I shows a form of
generator designed to employ internal field magnets. The field magnets are so
arranged (A Fig. 2) that a continuous conductor serves to excite them all, the
conductor (preferably of strip copper) being applied in such a manner that the
current flows round each magnet in the required direction as for example that
indicated by the numbers affixed, entering at 1 it passes by 2. 3. 4. 5. 6. 7. 8. 9.
&& to Y. and entering at a, and passing by b. c. d. e. f. g. h. i. j. k. &e it leaves by
Z&&c. When the machine is of large dimensions I prefer to make the cores of
the magnets hollow as aforementioned, one very convenient method of doing so
being to forge a piece of boiler plate into the form of a box one side of which is
discontinuous as shewn at K. K₁. The cores are furnished (generally at both ends)
with suitable pole pieces to enter the armature as shown at B. Fig. 2. In this form
of armature the conductor does not pass across the inner side of the armature as is
the case with the one hereinbefore described and represented by Fig. 1. but is made
ta cross and recross the periphery of the armature. For example passing from l.
to m. on the anterior side of the armature (A. Fig. 2.) it crosses the periphery and
passes to n. on the posterior side, thence to o. and p. (on the posterior side)
recrossing the periphery it passes from p. to q. r. 8. on the anterior side & &.
When the generator is required to give currents alternating in direction, it is only.
necessary to attach the free ends of the conductor to suitable contact rings or
collars. In order to further utilize the armature other conductors are interpolated
as for example that shown by the dot and dash line. I prefer to attach the ends
of these conductors to separate contact rings or collars which method of collecting
possesses a two fold advantage viz. (a) it permits of a number of distinct circuits
being worked from one generator and, (b.) minimises loss of energy by induction in
the work circuit, since (when several are used for each circuit) the strength of the
current in the work circuit is by this means rendered more constant. For this
purpose also the two (or more) armatures are keyed to the shaft slightly
in advance of each other, so that when one is delivering a current of
maximum strength, the conductor upon the other is in a less advantageous
position. I sometimes employ three or more armatures by arranging the
conductor upon the field magnets so as to form additional fields of force. The
generator may be made to yield currents in a number of circuits as hereinbefore
explained, all or any of such currents being continuous or alternating according as
a Commutator is or is not employed. It may be either self exciting or separately

page_text: excited and the currents produced may be of constant strength or constant e. m. f.
by setting apart a certain length of the conductor upon the armature and a certain
number of field magnets for the generation of a current for the production of an
initial and independent magnetic field. The combined effect of this initial field
and of the main field being to produce (the speed of the generator being constant)
a current of constant e. m. f. or constant strength according as the current varying
the strength of the main field forms part of the work or external circuit or of a
shunt or derived circuit of the said work or exterual circuit. When uni-directional
currents are required the ends of the conductor are connected up (as shewn
diagrammatically by fig. 3) to a commutator which consists of a number of contact
pieces (the number depending upon the number of fields of force employed)
arranged that the conductor upon the armature is in connection with the external
or work circuit by means of one pair of contact pieces so long as a current in one
direction is being induced and is disconnected when the conductor is in a neutral
position, and again put into communication with the work circuit by means of
another pair of contact pieces connected to the conductor in the opposite manner to
the preceding ones so that the direction of flow of the current in the work circuit
is constant. Figure 3 shows the method of connection (the lines i. i. o. o.
representing the ends of the conductor) and Figure 3a. a commutator constructed
upon this principle. In cases where but one (or but few) fields of force are
employed instead of causing the conductor to cross and recross the armature and
interpolating other conductors as hereinbefore explained with reference to A. Fig: 2.
I prefer to cover the armature by a number of conductors all the ends of which on
one side of the armature are metallically connected their remaining portions being
insulated and each connected to a contact plate, or instead of being metallically
connected they may be provided with contact pieces on both sides of the armature.
The armature may in the former case be very conveniently made solid and after-
wards slit up to form the various conductors. Where however the length of
conductor exposed to the action of the field magnets is insufficient to produce the
required e. m. f. both ends of the conductor are insulated one end being connected
to a contact plate the other being connected to other of the conductors so as to
produce the required length, and then to a contact plate. In machines of large
dimensions considerable friction takes place between the commutator and collecting
pieces and much inconvenience is occasioned by the wearing away of the collecting
pieces and Commutator plates. To obviate this I employ a form of collector shown
diagrammatically at Fig: 4 A. W. W. is a travelling contact piece (preferably of
flexible material such as copper strip of moderate thickness) and C. is the contact
collar or commutator to which it is held by means of the Guide wheels G. G.—To
enable the contact to be made at any point on the circumference of the contact
Collar or commutator the wheels G. G. are mounted in a moveable frame and to
preserve good contact between the travelling contact piece and the Commutator
they are kept in contact with the travelling contact piece by means of springs,
When it is desirable to make but a short length of contact the arrangement shown
at B is adopted, the travelling contact piece being kept in contact with the
Commutator by means of the wheel G which is mounted upon a spring or if rigidly
mounted is provided with elastic substance upon its periphery. When it is desired
to make a very long contact as for example in the case where each conductor is
provided with a contact piece as herein before described I employ the arrangement
shown at D. The travelling contact piece in this instance is made very flexible
(and which may consist of a number of strips, wires, plaited or braided webs, or
cables,) is guided by the wheels g. g. The length of contact may be varied at will
by increasing or diminishing the distance between the centres of g. g.
My method and apparatus for regulating electric energy (either by governing
the strength of the current or the e. m. f. of the same) consists essentially of an
epicyclic train of wheels the intermediary wheel or wheels of which is or are made
to effect the regulation by the differential velocity of the first and last wheels of
the train or of the matter driving and that driven by the train. Such being

page_text: produced by more or less work being thrown upon the train according to variations
in the electrical conditions of the work circuit, or by these variations directly
This regulation may be obtained in various ways according to the requirements of
the particular case, as for example, by varying resistances increasing or diminishing
the number of elements, if batteries or accumulators are employed, shunting
portions of the current in other directions, & &°. For the purpose of electric
lighting and the transmission of power I prefer to employ the following system:
One or more generators the field magnets of which are excited either by another
generator, or by the method herein before described. are employed during the time
when no use is being made of the work circuit to charge accumulators. During
this time the Conductor upon the armature or armatures of the excited generator or
generators may be arranged in multiple. The accumulators are divided into two
groups which for convenience may be called main and auxiliary The main group
is charged directly by the excited generator, whilst the auxiliary group is placed
in a shunt or derived circuit between the exciting and excited generators. This
system is provided with a Governor (hereinafter described) which varies the
intensity of the magnetic field of the excited generator and consequently the
amount of electrical energy developed in the work circuit in accordance with the
demands made upon it by the main group of accumulators. Such variation being
caused by the shunting of more or less current into the auxiliary group of
accumulators. These conditions obtain until the main group is completely charged
when the whole of the current will be shunted through the auxiliary group, In
doing so it may if required be made to stop the current, or the machine, or the
motor &c. In order to avoid the loss of Electrical energy by its conversion into
heat energy which is consequent upon the employment of a shunt of variable
resistance for varying the amount of current flowing into the auxiliary group of
accumulators, I generally employ a third group of accumulators and in this case
the Governor brings into or cuts out of circuit a greater or lesser number of
these accumulators. By thus increasing or diminishing the counter e. m. f. the
effect is exactly the same as varying a resistance. When it is desired to make
use of the work circuit or circuits the latter are attached to the accumulators
and excited generators (the conductor upon the armatures may now be arranged
in series) and the regulation of the amount of energy developed in the work
circuit will be effected by the Governor in a precisely similar manner to that of
charging the accumulators. At convenient intervals the small group of accumulators
is replaced by another taken from the main group (after discharge). It is of course
unnecessary to remove the accumulators themselves the substitution being most
conveniently performed by means of suitable switches. When it is not convenient to
use accumulators and the automatic regulating arrangement of generator herein-
before explained is not employed, I apply the conductor upon the field magnets in
sections, and connect the ends of the sections to the Governor, so that the latter
may couple them up in multiple or series according to the requirements of the
work circuit. I am aware that a method of regulating by varying resistances,
placed in circuit with the conductor upon the field magnets of the generator has
been employed, this however has the disadvantage that the current circulating in
the resistances is wasted. In my method no additional resistance is employed, the
variation in the resistance being obtained by varying the method of connecting up
the various sections upon the field magnets. This having the double effect of
varying the resistance and the number of convolutions through which the current
passes. When an exciting generator is employed (without accumulators as herein-
before explained) I generally prefer to apply the Conductor upon the excited
machine in sections, the Governor in this case causes the exciting current to traverse
these sections in multiple, or series, or combinations thereof, according to the
requirements of the work circuit, or the conductor upon the excited generator may
be continuous and the regulation be effected at the exciting Generator. In some
cases I prefer to regulate the electrical energy by varying the velocity of the
generator, in which case the governor hereinafter described is arranged to vary the

page_text: speed of the motor. Fig: I. Sheet 2. shows one form of regulator for carrying into
effect the principle herein before explained. The Epicyclic train in this case is
formed by the bevil wheels a. b. c. d. the intermediary wheels b. c. of which are
mounted in the spur wheel e. f. and are free to take up any position in a plane
parallel to the plane of e. f. The wheel e. f. being geared with the pinion g. any
motion of the intermediary wheels is imparted to the shaft H. H. Keyed to the
shaft H. H. is a drum K. which by its motion raises or lowers the weigh w.
The
last wheel a. of the train is the one to which the variations of work or speed are
communicated according to the variations in the electrical conditions of the work
circuit. There are obviously many methods of throwing on or removing the load,
or of varying the velocity. In this instance the wheel a, carries a very light
plate P. P. (preferably of aluminium if of dia-magnetic material or of soft iron if of
para-magnetic material) which revolves at a high velocity between the poles of
electro-magnets (not shewn in the figure.) Motion is imparted to the plate P. P.
from the shaft m. m. furnished with a fly wheel L. L. through the intervention of the
Epicyclic train. The intermediary wheels b. c. have a tendency to turn about the
axis P. M. in virtue of the force w, and also in virtue of the power transmitted by
them necessary to overcome the resistance to rotation experienced by the plate due
to the cutting of the magnetic lines of force. Under these conditions the inter-
mediary wheels of the train will instantly take up a new position for every change in
the velocity of P. P. caused by more or less work being thrown upon it by the electro-
magnets aforementioned. If the Governor be required to maintain a constant e. m. f.
the Conductor upon the electro-magnets (or solenoids) must form part of a shunt
circuit between the poles of the work circuit, if a constant strength of current it
must be part of the main circuit or a derived circuit thereof. Sometimes I prefer
to apply a brake or to grip the plate P. P, in which case I prefer to employ an
electro-magnet arranged as hereinafter described with reference to the re-action
armature of my improved regulating mechanism for electric lamps. When the
governor is of large dimensions and P. P. cannot be kept extremely light I sometimes
provide a shaft on the upper side of P. running at a higher speed than m. m. which
may at will be connected (by means of a clutch for example) to P. in order to
momentarily increase the velocity of P. In other cases I dispense with the plate P.
and cause the movement of b. c. by varying the speed of a. directly. Where great
sensibility of action is desired I govern the velocity of a portion of the apparatus
by a conical pendulum, or other method of obtaining a constant velocity a method
of carrying it into effect is shown diagrammatically at Fig. 7 sheet 5 and herein-
after explained in connection with my improved method of governing the action of
electric lamps. In order to make the motion of the intermediary wheels effect the
regulation, the shaft H. H. carries an arm o. o. upon which is mounted the
compound wheel w. w. which is free to traverse a circular tramway T. T. This
tramway is formed of a number of contact pieces q. q. &c to each of which is con-
nected one end of the conductor leading to whatever it is required to bring into or
cut out of circuit the end of the conductor leading from the same being connected to
the rail R. R. When the number of contacts is not very great they are arranged in a
circle as shewn in which case w. w. maintains its position on the shaft, if however
they are very numerous they are more conveniently placed in the form of a volute
in which case w. w. is free to move longitudinally upon the shaft so that it may
take up a position at any distance from the centre of motion dependent upon its
position upon the volute. In some cases I form the circular or volute shaped track-
of a continuous resistance. The contact pieces upon the periphery of the wheel
and upon the tramway are so arranged that the flow of the current is not inter-
rupted upon contact being disestablished with any of the contact pieces but is
made to pass through a resistance coil carried by w. w. or placed in any convenient
position. For example the contacts 1. 1. 1. &c. &c. and 2. 2. 2 &c. &c. are insulated
from the contacts 3. 3. 3. &c. but the set 1. 1. 1. &c. is connected to the set 2.
2. 2. &c. by a resistance. When therefore one of the contacts 2 is in contact
with one
of the contacts q. upon the tramway, and the corresponding

page_text: .
contact 1. is in contact with the rail R. R. upon the tramway the current must
pass by means of the resistance, whilst the contacts 3 &c. make direct contact
between the contacts q. and the rail. There are also other methods of arranging
the contacts but that shown suffices to explain the action of the Governor. The
object in employing the epicyclic train arrangement is to obtain great promptitude
of action by drawing upon the energy stored up by the rapidly rotating parts, and
to further promote promptness I sometimes prefer to use a current from a separate
source for exciting the electro-magnets, or solenoids, or other device, employed for
throwing on and removing the work from the train, and to put them into circuit
with the separate source by means of any suitable delicate arrangement similar
for example to a polarized relay used in telegraphy: Where however the variations
in the work circuit are not considerable and promptness in action is not of so great
moment the compound wheel and tramway arrangement may be actuated directly.
For this purpose I prefer to employ a moveable electro-magnet or solenoid acted upon
by stationary electro-magnets or solenoids as hereinafter explained in connection with
the electric meter. In cases where currents of but moderate strength are employed I
• make use of another form of regulator in which the contacts are made or broken
by the movement of a fluid. One form of regulator upon this principle is shewn in
Fig 2 Sheet 2. It consists of a tube a. a. constructed either wholly or partially of
an insulating material in this case the upper part of the tube is of conducting and
the lower of non-conducting material. Into the lower part of the tube are placed
the contacts. The accumulators or whatever are connected to these contacts are
brought into or cut out of circuit by a conductor moving in the interior of the tube,
and actuated by the motion of the liquid insulator. In this case the Conductor
(shown at the centre of the tube) is formed of a small quantity of mercury kept in
position by the two flanges f. f. which are connected together. Connected with the
tube are two vessels v. v. provided with flexible diaphragms. These diaphragms are
moved (according to variations in the work circuit) by means of the electro magnets
m. m. and their movement (much amplified) is transmitted by the liquid to the
moveable conductor f. f. In order to prevent the current being interrupted the
contact pieces are bent so as to lie parallel with the axis of the tube and the
moveable conductor is made of such length that contact is made with the succeeding
contact piece before it has been disestablished with the preceding one, the pointed
form of the contact offering a gradually increasing resistance until the contact is
entirely broken.
When electric accumulators are employed it is necessary (in order
to attain a high efficiency) to arrange (a) for automatically regulating the current
so that a too great volume may not pass, and (b.) to provide means whereby the
circuit may be broken when the e. m. f. of the accumulator exceeds that of the
generator. This second provision is especially necessary when the speed of the
motor driving the generator is liable to fluctuations as for example in the case of a
windmill. For this purpose I employ a regulator which fulfils the requirements by
the action of a current upon a delicately suspended or balanced permanent magnet
or piece of para-magnetic material polarized by induction. Fig I. Sheet 3. shows
one form of apparatus I employ for this purpose in which m. m¹. m¹¹. represents a
permanent magnet delicately balanced at the point m. Jointed to the permanent
magnet or the beam b. b. is a small arm or lever l. 1. free to turn about the axis b.
This lever carries the beam c. c. A stop s. is arranged in relation to the small beam that
sufficient freedom of motion is allowed to the permanent magnet to complete or
break the circuit by means of the contact d. (preferably by its dipping into a
mercury cup not shown in the figure) but upon the motion being continued (caused
by the passage of too powerful a current) the stop engages with the lever and
causes the bean c. c. to break contact at d. and if required make contact at e. The
action of the regulator is as follows:-one of the magnet coils say a. has a high
resistance and is placed in a shunt circuit between the generator (or other source)
and the accumulators to be charged whilst the other magnet b. is placed in the
direct or main circuit. I sometimes employ only one magnet wound with both the
main and shunt conductors. The conductor upon the magnet a. is so wound that

page_text: .
its pole shall attract the pole + of the permanent magnet, when the current is
flowing in the required direction, consequent upon this attraction the beam is tilted
and contact is made at d. which completes the main circuit. The main
current now flows and passes through b. in such a direction as to cause it
to repel the pole + of the permanent magnet. When no current is flowing
the contact at d. remains open the beam being tilted up by the pull
of one of the springs shown say c. or by a counterweight.
When a
current of the required strength is flowing the beam raises the knife edge k.
until it (the beam) comes into contact with the knife edge . of the other spring.
The second spring E. is set so that it gives, and allows the beam to rise imme-
diately the strength of current for which it is set is exceeded, but as the stop S is
in contact with the lever l. 1. any tilting of the main beam causes the secondary
beam to break contact at d. and when required make it at E. In making the
contact at E. it may ring a bell or perform any other work desired, but I generally
prefer to connect it to the governor hereinbefore explained (not in this case
employing the train) which immediately reduces the strength of the current, the
beam then falls the contact is re-established and the charging proceeds. When the
e. m. f. of the generator gradually falls off the spring c. gradually overcomes the
pull of the magnets and the contact at d. is disestablished. If however the e. m. f
falls off abruptly such for example as is caused by a great reduction in the speed
of the generator, by the coming off or slipping of the driving belt &c. &c. the
polarity of the electro-magnets is instantly changed and the beam suddenly tilted
up, its motion being accelerated by the spring. In some cases I prefer to suspend
the magnet by a spring or otherwise, and where great sensibility is required I
sometimes employ soft iron polarized by induction by a permanent magnet or
other suitable means.
In the distribution of electric energy to various consumers for the purposes of
electric lighting and the transmission of power (as is at present accomplished by
coal gas) it is necessary to providé means of registration and this in a manner as
devoid of technicality as possible. For this purpose I suppress all measurements
of current, passing, e. m. f. of the current & &c. and cause the alterations in the
electrical conditions of the work circuit as for example variations in resistance
caused by the ignition, extinction or employment of more or less lamps, or
variations in counter e. m. f. caused by the starting, stopping, or employment of
more or less motors to record by suitable apparatus the number of lamps or motors
in action and to give the result in lamp-hours and horse-power-hours respectively.
To this end I construct an apparatus one portion of which always moves with a
constant velocity and I cause the alterations in the electrical conditions of the
circuit to alter the ratio which the velocity of the registering apparatus bears to the
constant velocity of the other portion of the apparatus. The apparatus may be
driven by any suitable means, but in most cases I prefer to employ a miniature
electro motor. I am aware that it has been proposed to employ electro-motors to
give a constant speed in electric current meters to a portion of the mechanism and
to transmit the motion of this to a counting apparatus at variable speeds according
to the amount of current flowing. I do not employ electro-motors for this purpose
since the mere measurement and registration of current passing gives no indication
of the amount of electrical energy given to a circuit, but I sometimes employ them
in conjunction with electric energy meters or apparatus for recording lamp-hours &
hereinafter described. Fig I Sheet 5. shows diagrammatically one form of apparatus
for carrying this into effect. The shaft A. A. is connected to any suitable
apparatus for imparting motion to the cone B. the velocity of which is rendered
constant by the action of the chronometric governor (shown to the right of the
figure) upon the motor. The construction and action of the governor is similar
to that of the governor hereinbefore described The motion of B. is communi-
cated to C. by means of a strap, sphere, or other suitable means, but preferably
by means of a sphere a method of mounting which is shewn at fig. 2.
The motion of C. is transmitted by the epicyclic train d. e. f. to a counting.

page_text: apparatus shown at the upper part of the figure. Motion is also imparted to the
registering apparatus from B. by means of g. g. gearing with h. h. which carried the
wheel E. The registering apparatus is therefore actuated differentially and the
gearing is so arranged that the motion of f is nil. when the ball b. is in a given
position which is generally at the top or bottom of the cones. The differential
motion off is varied according to variations in the electrical conditions of the
work circuit by raising or lowering b. and the registration is made accordingly.
Thus for example if it be required to register the number of lamps in operation
when none are in use the sphere will occupy such a position that the motion of f. is
entirely destroyed, for one lamp at work it will be moved so that f. revolves with
a certain velocity-for two lamps at double that velocity, three lamps treble &°.
Therefore as B. revolves at a certain number of revolutions per hour the result
will be given in lamp-hours. The wheel f. is (when necessary) connected to the
counting apparatus by suitable gearing to reduce the speed so that the first pointer
(carried by the pinion K.) will revolve once in an hour for one lamp, twice for
two, &.&. g. h. i. j. represents an epicyclic train for effecting this similar to that
herein after described with reference to my improved feed mechanism for the lamps.
Any convenient method of altering the position of b. may be employed. Figs. 3
and 4 show methods I make use of. In Fig. 3. 8. n. represents an electro-magnet or
solenoid free to turn about the axis a. This is acted upon by electro-magnets or
solenoids 8¹. n¹. s². n² 8³. n³. 84. n. Turning with the shaft a. is a wheel w. w. which
gives motion to the shaft t by means of the pinion p. The shaft t may be made
to alter the position of the sphere by any suitable means. If it is desirable that t
turn through equal angular distances for equal increments in the strength of s¹. n¹.
82. n². 8³. n³. 8¹ n' any suitable means of varying a certain force experienced by s. n
according to its position with relation to s². n. 8². n². 8³. n³. s¹. n. may be employed,
as for example the spring (or weight) and cam shown. In fig: 3 s. n. could be
affected either by the strength of the current or of its e. m. f according to the
winding of s¹. n. s². n². 8³. n³. 8¹. n. Fig: 4 shows the same arranged to be worked
by changes in the resistance of the circuit, in which case two of the electro-
magnets or solenoids are in the main circuit, and two in a bigh resistance shunt, as
for example s'. n¹. and 82. n². in the main, and 83. m³. and 84. n. in shunt. Where it
is required to register the total amount of energy passing 8. n. must be affected
both by the e. mf and strength of the current. In this case they may be
arranged as in fig: 3 two high resistance magnets or solenoids being in the shunt,
and two of low resistance in the main, or the magnets or solenoids may be
wound both with high and low resistance conductors. In cases where it is only
required to indicate either the strength of the current e. m. f, resistance, energy, &.
and not to register them these may be used separately forming an ampére meter,
ohm-meter, volt meter, and erg meter, according to their arrangement Another
form of registering apparatus or meter is shewn diagrammetically at fig: 5 sheet 5.
In this the speed of the Cone C. is varied according to variations in the conditions
of the work circuit the speed of B being constant as before, One very convenient
method of varying the speed of c, is to drive it by means of a small electro Motor
or electro Motors performing any work which is proportional to the velocity. If it
be required to register the total energy passing the velocity of C must be affected
both by the strength of the current and the e. m. f of the same. A convenient
method of effecting this is to employ two motors the armatures of which are
preferably keyed to the same shaft, one of low resistance driven by the main
current and one of high resistance driven by a current flowing in a circuit forming
a shunt between the ends of the circuit, the amount of electrical energy passing in
which is required to be known, but I generally prefer to employ a double armature
Motor as fig: 2 sheet I one armature being of high resistance and the other of low,
and one portion of the field magnets of high and the other of low resistance, or if
only one armature be employed both the armature and the field magnets have both
high and low resistance circuits. The action of the apparatus shewn in fig: 5 is as
follows, any variation in the velocity of C is communicated (temporally) to B

page_text: may be
which causes the wheel d. e. to revolve, and this gearing with the nut n. upon the
screwed rod r. r. instantly alters the position of b to that which it must occupy in
order to drive B at its proper speed. The alteration in the position of
made to affect the registering apparatus by means of C. B¹. h. h. g. g¹. d¹. e¹. ƒ¹. &º.
as already explained. If for example it be required to give the amount of energy
passing in HP hours, C will revolve at a certain speed for 1 HP (or fraction thereof) at
another for two HP&. &. and this being communicated to the registering apparatus,
will cause the units pointer (affixed to K) to revolve once in an hour for 1 H. P twice
for 2 H. P &.&. If the result is not required to be given in H. P hours, simply the
number of revolutions C has made in a given time will give the amount of energy
which has flown through the circuit. Direct acting instead of differential gearing
may be employed when desirable Fig. 6 sheet 5 shews a method of effecting the
registration by means of a variable feed. In this the cam c revolves with a
constant velocity (being preferably driven by Clockwork which is set in action
when a current flows) and the registering apparatus is driven by the wheel w to
which a variable feed is imparted according to the position of the connecting beam
b. b. b. b. To show the speed of the Generators &c. I employ an apparatus similar
to fig. 5. The alterations in the speed of the motors, generators, &. varies the speed
of C, and the position of 6 shows the ratio which the speed of c bears to the
constant speed of B. The speed of B being known a pointer p shews on a scale -
8. 8. the velocity of the machinery at any moment. Where it is desirable to have
a number of dials showing the speed of the machinery at any distance from it I
cause the movement of b to actuate step by step mechanism at each of the dials.
For the illumination of small spaces I prefer to employ lamps giving their light
by the incandescence of a continuous high resistance conductor placed in a vacuum,
preferably those described in the Specification of a patent granted unto me and
bearing date the third day of December one thousand eight hundred and eighty one
N°. 5286 with the following additions. These consist in cheap and simple methods of
(a) connecting the incandescing conductor to the conducting wire or wires (b) forming
the joint between the lamps and the electroliers, brackets, and other fittings, and
between parts of the conductors themselves, (c) making and preserving contact
in the moveable joints of the fittings &°. and (d) in simple switches or taps for arresting
or allowing the current to flow. My improved method of connecting the incandescing
conductor to the conducting wires consists in placing the ends of the incandescing
conductor (or the enlargements referred to in the Specification aforementioned)
which may be solid or in halves, into a metallic socket preferably split in one or
more places to secure elasticity. Through this socket, or the bottom of the same,
I drill a hole or holes at right angles to the plane of its axis and also one or more
(generally smaller in diameter) in a direction parallel to its axis so as to run into or
pass through the former hole or holes. The ends of the conducting wire or wires
after having been sealed into the glass is or are passed up the hole or holes parallel
to the axis of the socket and into or beyond the holes at right angles. Metallic
pins are then inserted in the latter which by forcing the conducting wires
from their original positions make good contact and at the same time firmly
key the socket and with it the incandescing conductor to the conducting
wire or wires. Fig: 3 sheet 4 shows methods of carrying this into effect.
Elevations of the sockets are shown at a, a, and sections at b. c. d. e. The
conducting wire c is first passed up the vertical hole and the pin p forced
into the horizontal hole which makes contact and keys the socket to the con-
ducting wire as shewn at a and c, b shows the same except that the pin passes
through the enlargement of the conductor in which case the socket need have no
bottom. aande show the same as a and c when a number of conducting wires
are employed, sometimes instead of making the horizontal hole the same diameter
throughout, I enlarge one end thereof as shown at d and drive the pin in the small
portion which forces the conducting wire into the larger portion and thus makes
conduct and keys the socket to the conducting wire as shown. When a very large
number of conducting wires are employed. I form the lower portion of the socket

page_text: of a separate piece as at F. The conducting wires after having been passed through
the holes have their ends bent over.and the upper portion of the socket is then
screwed down upon them. The sockets and incandescing conductors are shown in
the complete lamp, Fig: 4. In each of the methods described a broken incandescing
conductor may quickly be replaced by a new one, and for this purpose. I make the
joint between the globe and the other portion of the lamp (as at x. x.) by means of
an easily fusible substance in order that the globe may be removed for the renewal
of the incandescing conductor. The lamp shewn is provided with loops to be
connected to the conducting wires in the ordinary manner. My improved.method
of attaching the lamps to the fittings is as follows. The electrodes of the lamp
(instead of being. formed into loops as shewn) are attached, to contact plates or
pieces one or both of which is or are provided with a corrugation or deep
indentation. In order to attach these contact pieces to the lamp in a rigid manner
they are together with the lower part of the lamp placed in a suitable mould the
contact pieces being temporarily held to projections on the inner side of the mould,
which projections are slightly narrower than the contact pièces themselves. 'Into
this mould is then cast or pressed a suitable insulating substance. By this means
(the contact pieces being slightly larger than the projections to which they are
attached) the contact pieces are rigidly attached to an insulating stem, and, this
latter is rigidly attached to the lamp. The conducting wires (leading to and from
the source) are connected to one or more insulated springs the extremities. of
which are moulded to the form of the indentations or corrugations of the contact
pieces. The lamp is held firmly in position by the projections upon the springs
falling into the corrugations or indentations of the contact pieces. A method of
carrying this into effect is shewn in Figs: 5. 6. 7 and 8 sheet 4. The contact pieces
are represented by c. c. c¹. c¹. the indentations; being shewn at i. . The. contact
pieces are temporarily.held to projections on the sides of the mould m. m. fig., 5 by
the tommy screws t. t. Into this mould the insulator is placed, which forms the
stem with contact pieces attached shown in fig. 8. The conducting wires (from the
source) are connected. to the insulating springs S. S. Figs 6. 7. and 8 whose
extremities are shaped to fall into the indentations i. i. These springs are placed
within a socket v. v. v. v. into which the insulating stem just fits. In order to
insure the lamp being always introduced into the socket so that the contact pieces
are exactly opposite the springs, the socket is provided with guide pieces g. g. g¹.
which guide the insulating stem by means of the recesses formed in it by the
projections on the interior of the mould. Fig: 7 shows the socket (part section) at
right angles to that shown by fig. 6. Fig. 8 shows a complete lamp (the lower part
in section) with this improved method of affixing The lower part of the socket is
generally tapped to suit the present thread employed in gas fittings. To attach the
lamp to the conducting wires (from the source) and to the electrolier or other fitting
it is only necessary to push it into the socket when the convex projections of the
springs falling into the concave depressions of the contact plates (or vice versa) makes
good contact and retains the lamp firmly in position. To detach it, it is only necessary
to pull it with sufficient force to cause the springs to yield and thus extricate their
projections from the indentations of the contact plates when the lamp will become
detached. It will be observed that the whole of the contacts are within the socket
which may or may not be of an insulating material consequently the lamps may be
removed or replaced whilst the current is on, it being impossible even by
carelessness to divert the current. This method of making connection is applicable
to all ordinary junctions especially where it is desirable to be able to couple up and
uncouple expeditiously, as for example for making connection between Railway
carriages. Fig. 9 shews a coupling arranged for connecting up two portions of a
conductor or cable. The only deviation from the afore described method being that
both male and female ends are provided with sockets, the advantage obtained by
this addition being that it is impossible to short circuit the current whilst the
connection is asunder. In couplings intended for use between Railway Carriages
and other places where it is desirable not to interrupt the flow of the current at the

page_text: moment of coupling and uncoupling, I slightly alter the shape of the male end and
place between the springs and the contact pieces short circuiting pieces so arranged
that the circuit is completed in both portions of the couplings before it is
disestablished between the two. The connections in the moveable and swinging
joints of the fittings are made in a similar manner, except that rings, discs, or balls
are employed instead of or in conjunction with the springs. The ends of the arms
of the fittings which are to be connected by a swinging or universal joint are
formed into hollow chambers provided with apertures for the introduction of the
insulating substance. Instead of the tapering hollow plug used in gas fittings, an
ordinary solid or hollow parallel pin is employed. To form the joint two concentric
rings connected to the conducting wires are placed in position with the pin as
centre, the bottom of the chamber is closed by a smooth surface and the insulating
substance introduced, by this means the rings are held rigidly in position and attached
to the sides of the chamber and insulated. The companion end of the fitting is
treated in like manner and when the joint is put together the rings slide upon each'
other and preserve contact in whichever direction the joint may be turned. In
order to insure good contact I generally counter-sink springs into one of each pair
of rings which may when more convenient be attached to a solid substance.
Fig 5 sheet 3 shows a bracket fitted with my improved joints, in which
a. a. b. b. c. c. d d. and a' a' b². b¹. c¹. c¹. d¹, d¹ represent the rings to which the
ends of the conductors are attached. When the fittings themselves are made use of
to form part of the return circuit, one pair of rings will suffice. The pins about
which the joints turn are shown by p. p. and p¹ p'. The method of forming
universal, ball and socket joints &c. is very similar. The taps are of the following
description. There are two requirements which a tap or switch should fulfil (a) to'
make and preserve good contact and (b) to reduce as much as possible the amount
of sparking which takes place when contact is broken. For currents of moderate
strength such as are employed in incandescent electric lighting the sparking will be
sufficiently reduced if the contact be disestablished very quickly. For this purpose
switches are generally made with rigid contact pieces, and the movement of the
moveable portion or switching piece is accelerated by the employment of a spring
generally coiled around the spindle carrying the switching piece, stops being properly
placed to limit the movement of the latter. My improvement consists in forming the
contacts of springs instead of rigid pieces and avoiding the use of the accelerating
spring or springs by giving to the contact spring or springs such a form that it or
they will of itself or themselves urge the switching piece forward, whilst to obviate
the use of stops I form in one or both of the contact springs an indentation into
which a portion of the switching piece falls and is thus firmly held in position.
Two advantages are obtained by this device 1st the tap or switch is much simplified
and 2ndly the contact is always good as the pressure of the springs keeps the surfaces
firmly in contact, and the friction between the springs and the switching piece
ensures the contact surfaces being always kept bright and clean. Fig. 6 sheet 3
shows a method of carrying this into effect. In this S. S. and St. S' are the
contact springs, and p. p. the switching piece. The spring S¹. S¹. is very elastic
and has forined in it the bend or indentation shown at b which indentation is
slightly to the right of the centre line a. a. of the tap when the tap is turned so as
to make contact and allow the current to flow, the spring is bent up into the
position shown, and the switching piece is firmly held in this position by the
pressure of S. S₁ forcing it against b. When it is desired to arrest the flow of
the current the handle HH of the tap is turned, and as soon as the switching
piece has turned so that its upper point is on the other side of the centre line the
force of St. S. tends to move the switching piece in the opposite direction namely
that in which the handle is being turned. When it has attained the position
shown at A S S¹ acts very powerfully upon it, at which point it is just leaving
the contact spring S. S. and causes it to fly to the position shewn at B, here in
consequence of the end of the switching piece coming into contact with the spring
S. S. its motion is arrested, the requirements being fulfilled without the

page_text: employment of stops or auxiliary springs. For currents of great strength however
this process of quickly breaking contact is insufficient to prevent the burning of both
contact and switching pieces. Switches for use with powerful currents are there-
fore generally provided with massive contact pieces so disposed as to easily
re-surfaced or filed true from time to time, and the switching piece is so arranged
that it may be filed and set up to the contact pieces as they become thinner. In
addition to this objection arising from the inconvenience and expense of having
repeatedly to make good the contact surfaces there is a still more important one,
since it is found that upon each act of breaking contact a small portion of the
surface is brought to a molten condition. The surfaces being thereby roughened
upon connection being re-established the surfaces do not bear properly upon each
other, consequently the electrical contact is not good and a resistance is offered to
the passage of the current. My improvement consists in the employment of a
switch so constructed and arranged that when it is desired to disestablish contact
a very small resistance is at first offered to the passage of the current which is
gradually increased until it becomes very great when contact is disestablished.
By this means the strength of the currents is so far reduced that the spark formed
upon breaking contact is harmless and does not take place upon the contact piece
at all. I employ two methods to accomplish this (a) by diverting the current
through a path of very small resistance, and gradually increasing this resistance
until it becomes very great or (b) I gradually insert the resistance in the
original circuit each having its advantages in particular cases Figures 7. 8.
and 9 sheet 3 slow diagrammatically methods of carrying this into effect.
In Figure 7 a number of contact pieces insulated from each other c¹. c. c³.
&% are each provided with a resistance and so arranged in relation to
moveable contact pieces, that the movement of the switch handle first couples them
in parallel, secondly, gradually diminishes their number in parallel, and thirdly
gradually couples them in series. The action of the switch in this case is as
follows G represents the generator (or other source) and w the work circuit,
8, 8, are the contacts at which the circuit is broken. As shewn in the upper part
of the figure the circuit is completed by the plate pl. p. Upon the switch handle
being moved the plates pp and p'. p. move from left to right and in doing so
couple the resistances in parallel directly p p makes contact with c, which occurs
just before p, p, leaves 8, 8, Under these conditions the resistance in the circuit is
very low (in practice à large number of resistances are employed but only a few
are shewn in order to make it more clear) the motion of p, p, p, p, being continued
the number of resistances in parallel is gradually diminished until only the last
remains, (as shewn by the dotted lines) just as this is also being cut out the first is
introduced by the plates p², p², p³, p³, (shewn in the lower part of the figure). The
motion of these being continued they are gradually all coupled in series and when
the plates arrive at the position shewn by the dotted lines contact is broken. This
action may take place in the main circuit when desirable. In figure 8 one end of
the conductor is attached to the contact c and the other to the switching piece p.
The resistance is mounted upon a wheel or roller forming a kind of rheostat (the
resistance being indicated by the black portion). In the position shewn the work
circuit is complete. To break contact the end of is drawn down which causes
the rheostat to revolve by means of the pinion and quadrant shewn. The spring 8,
now leaves the insulating piece i and just as the switching piece p leaves the
contact c, the spring s makes contact with e which is in communication with G,
the motion of the lever being continued, the resistance gradually increases until it
becomes very great, when the spring is again brought on to the insulating piece
and contact is broken. The object in employing a separate current is chiefly
that the latter inay be promptly switched on and off. There are however many
instances where it is of great importance to be able to switch the current on
and off very gradually. This is especially the case in the transmission of power
for Electric Railways &o, and it is also of great importance in electric lighting,
where the current is generated mechanically in order to prevent sudden and severe

page_text: strains being thrown upon the motors. For this purpose I introduce the resistance
into the work circuit. Figure 9 shews diagrammatically a switch arranged for
this purpose.
In the position shewn at a, the current is on, the circuit being
completed through 8, e and d whilst in the position shewn at 6 the current is off.
The stops t and t¹, are provided so as to make it necessary to turn the lever as
shewn by the arrows which causes the current to be gradually thrown on and off.
For ordinary purposes of illumination Electric lamps may be used either quite
exposed or enclosed in any suitable shade or globe. When however there are to be
employed in or in the vicinity of very inflammable or explosive substances or
liquids, or explosive mixtures of gas and air, as for example in Coal Mining,
I prefer to enclose them in an outer globe or lantern furnished with the
following safety appliance. My improved automatic safety appliance consists
of an automatic switch or contact breaker and method of actuating it, whereby
the passage of the current is immediately arrested (preferably at some distance
from the lamp as for example in a suitable wall box, or altogether without
the Mine,) upon any portion of the outer globe or lantern becoming damaged
or broken and also where desirable to effect the same upon the failure
of the lamp itself. To this end the lamp is enclosed in an outer case or
lantern (which may be wholly or partially of glass) and this outer casing is either
evacuated or filled with a liquid or gas under pressure. The conducting wires are
brought to the lamp and connected thereto as hereinbefore explained, with this
addition that one of them is also connected to a contact piece of a switch or contact
maker actuated by any change of pressure taking place in the outer case afore
mentioned. One method of carrying this into effect is shewn in Figure 2 Sheet 3,
in which a, a, a, a, represents the outer casing c, c, the contacts' in connection by a
system of levers with the vacuum chamber v, v, whose sides are flexible and are
distended by means of the spring 8, 8. One of the contacts is in connection with
an electro magnet or solenoid actuating a switch or contact breaker placed in any
convenient position and at any distance from the lamp (and preferably working in
a liquid insulator if placed in the Mine). A method of constructing such a contact
breaker is shewn in Figure 3. In this m, m, represents an electro-magnet actuating
an armature a, the movement of which releases the detent d, allowing the end b of
the beam b b'. to descend (it being weighted by the weight w). This movement
disestablishes contact at the point c. The whole is placed within the box xxx
which may be filled with a liquid insulator, so that no spark can be produced in
the atmosphere of the Mine or other dangerous position. The action of the
appliance is as follows-while all is working well, and under normal conditions,
the contact maker in the lantern remains open and the current flows through the
lamp, should however the lantern become damaged (be it only a crack in the glass)
the atmospheric pressure is admitted (if the outer casing has been evacuated), or
the pressure removed (if liquid or gas under compression be employed) and the
contact maker closed, the effect of which is that a current is sent through the coils
of the electro-magnet or solenoid afore mentioned and the current arrested by the
contact breaker in the wall box (or other position) being opened. It will be
observed that in this operation no contact is broken in or near the lamp and
consequently no spark can be produced except in the wall box or other safe position.
The lantern may now be opened and a new lamp inserted without danger of short.
circuiting the current and thereby producing sparks and no current can be sent
through the lamp until the lantern has been properly put together, the vacuum (or
pressure) restored and the switch (in the wall box or other position) re-adjusted.
If required the switch may be actuated when the incandescing conductor of the
lamp fails (if an incandescence lamp be employed) or any failure takes place, if an
arc lamp is employed, by providing the contact breaker with a high resistance
magnet (placed in a derived circuit) or both high and low resistance coils may be
wound upon the saine magnetic core. This however is not necessary, for
immediately an attempt is made to open the lantern the current is arrested as if
the same had been damaged or broken. In places where it is desirable to provide

page_text: each lamp with its own primary or secondary battery or other means of producing
the current as for example where there is danger of sparking by damage being
done to the Conductors, or where it is more convenient to employ an entirely
detached lamp, I cause the interruption of the continuity of the circuit to take
place within the lantern. The point where the contact is disestablished must
obviously not be in communication with the atmosphere of the mine, or other
dangerous position. One form of apparatus for effecting this is shewn in Figure 4.
v, v, v, v, represents a chamber having flexible sides distended by the springs 8, 8, 8, 8,..
The movement of the sides causes contact to be broken at the point c, Many other
mechanical combinations may be employed with almost equal advantage, liquid
insulators may or may not be employed the chambers may or may not be
evacuated &o, &c. according to the particular form of apparatus employed. When
secondary batteries or accumulators are employed it is necessary to provide a
commutator in order that the lamp may be included or excluded from the circuit
according as the accumulator is being charged or discharged. In order to actuate
this commutator without the necessity of opening the lamp, or of having any
moveable material connection between the said switch and the exterior of the
lamp. I employ a magnetic or electric switch, which may be actuated inductively by
magnets or currents exterior to the lantern. When the accumulators are to be
charged it is simply necessary to place the lamps on a suitable stand, furnished
with suitable means of acting. inductively upon the said commutator; and when
they have been charged (and it is required to discharge them through the lamp) it.
is simply necessary to remove them from the said stand.
For the illumination of large spaces I prefer to employ lamps giving their light
by means of the electric arc. The chief requirements to be fulfilled in arc lamps
for the production of steady lights are ;-that they should be provided with suitable
but simple mechanism for maintaining a constant strength of current if one only
is to be used in circuit, or to maintain a constant difference of potentials at the
two sides of the arc if several are to be worked in series, that they should be
capable of imparting a very delicate feed to the Carbons at very short intervals of
time. For this reason the moment of inertia of the governing parts should be very
small so that the mechanism may promptly respond to any slight variations in
the required conditions, and that they should be able to instanteously bring the
Carbons into contact in the event of a momentary cessation of the current such as
that for example which frequently takes place through the dropping off of a small
piece of one of the carbon electrodes. It is therefore necessary first that the
electrical arrangements be such that the slightest alterations in current strength
in the one case or of the resistance of the arc in the other, be caused to act on the
feed mechanism and secondly that the moment of inertia of both this governing
device, and of the whole mechanism be very small. In order to obtain delicacy
in the feed all lamps hitherto constructed have been provided with long trains of
wheelwork, the objects being first to reduce as much as possible the work done
by the governing device, and secondly to reduce a comparatively coarse feed
by the governing device to a very fine one of the carbons themselves. The feed
is generally governed by the movement of heavy armatures or solenoid cores or
plungers. The objection to this method of importing a delicate feed is, that the
moment of inertia of both the train of wheels and the governing device is great
and consequently the delicacy of feed is obtained at the expense of promptness..
My improved regulating mechanism for electric lamps and method of governing
the same, consists firstly in substituting for armatures or solenoid cores, a very
light and delicately suspended or balanced electro magnet or solenoid working
under the influence of one or more controlling electro-magnets or solenoids.
Figure 1 Sheet 4 shews one form of Apparatus for regulating the electric arc
by means of the moveable electro magnet afore mentioned, and which for brevity
I call a reaction or reciprocal armature. The figure shews the reciprocal armature
arranged to regulate the feed of the carbons by controlling the movement of an
ordinary train of wheels, which I find sufficiently sensitive for small lamps, but

page_text: for those of larger dimensions I prefer to employ an epicyclic train as herein before
mentioned. The apparatus shewn in the figure is arranged to work differentially,
and its construction and action will be understood from the figure and the
following description. The reaction armature a, a, is delicately supported in
5 the frame b, b, b, b, which also carries the train of wheels. Fixed to the armature
is a detent c, c, which engages with a wheel or fly shewn by the dot and dash,
line d, d, being the last of a train, the first wheel of which is geared with
the rod r, r, of the carbon holder, Projecting from the frame b, b, b, b,
are plungers p, p, p², p¹¹, working within the solenoids 8, 8, 81, 8, (when the lamp
is intended for use with alternating currents I employ solenoids instead of these
plungers.) The action of the mechanism is as follows: so long as no current flows
the frame b, b, b, b, remains in the position indicated, when however a current is
flowing the plunger p, p, is drawn up into the solenoid s, s, (the amount of motion
being regulated by the spring f,f,) by which movement the arc is formed. The
arrangement and method of winding the reaction armature varies with the,
requirements but in this particular instance it is as follows. The conductor upon,
the armature forms part of a shunt or derived circuit, in which the solenoid 81, 81, is.
included and the conductor is arranged on the armature and solenoids in such a
manner as to produce the polarities indicated. Mutual repulsion therefore takes
place at a, whilst mutual attraction takes place at a', This arrangement is adopted
in order that the couple may not vary with the position of the armature. When
the required conditions are fulfilled the attraction at a¹, just balances the repulsion
at a, and the pull of a spring g, g, (the spring being introduced in order to vary;
the length of arc at will). When however the resistance (or counter e, m, f) of
the arc increases in the slightest degree, the attraction at a¹ is increased, the
armature releases the detent and allows the mechanism to feed.
When any,
material alteration takes place the whole mechanism descends. By this means the
apparatus is capable of imparting both a coarse and fine adjustment to the carbons.
When it is desired to actuate the mechanism by variations in the strength of the
current the conductor upon the reciprocal armature forms part of the main circuit
(it need not however form part of the main conductor, but may be in a derived,
circuit of the same which is more convenient in practice as a thinner conductor
may be employed). I find the arrangement of the reciprocal armature shewn in,
Figure 1 to be very sensitive, but when it is desirable to still further increase its
sensibility, I arrange it as shewn in Figure 2. In this arrangement the armature.
has not a continuous para-magnetic core as in Figure 1, but its centre portion all is.
of diamagnetic material. One end of the armature which is in the vicinity of the
high resistance magnet or solenoid is wound with a conductor forming a continuation,
of the high resistance circuit, and the other end of the armature, (which is in the
neighbourhood of the magnet or solenoid in the main circuit) is wound with a
Conductor forming part of the main circuit (although for convenience it may be
in a derived circuit of the latter as explained above). There are other methods of.
winding to suit certain requirements. By the employment of an epicyclic train I
ain enabled to obtain any degree of delicacy in the feed with a very few wheels.
These wheels may be very small and light and in any case their number need not
exceed four. Whilst by the employment of the small electro-magnet or solenoid
moveable in relation to the controlling magnets or solenoids I obtain great.
sensibility of action. There are obviously a great number of ways in which an:
epicyclic train may be arranged to fulfil the requirements of an electric lamp or;
regulator. Figure 8 Sheet 5 shews a very convenient arrangement of a train of
four wheels. In this case the intermediary wheels b, c, (whose axes are moveable) are:
mounted upon an escape wheel or fly F (with which a detent may engage as in.
Figure 1 Sheet 4). The rack of the carbon holder gears with d whilst d is dead.
By employing spur wheels having suitable numbers of teeth the ratio which the:
speed of d, bears to that of F may be made as great as requisite.
Thus if a,:
has 101, b, 100, c, 99 and d, 100, then when d, has made one complete revolution:
F will have made ten thousand. In some cases instead of using spur wheels I employ:

page_text: Where very powerful
wheels working by bands or cords to attain the same end.
currents are employed as for example in Lighthouses in Lights for Military and
Naval purposes &c. &c. I prefer to regulate the arc by means of the differential
velocity of a body moving under the influence of the current, and another having
a constant (or approximately constant) velocity. One form of apparatus for 5
carrying this into effect is shewn by Figure 3 Sheet 2 the mechanism being
somewhat similar to the epicycli governor Figure 1. An epicyclic train a, b, c, d,
is driven by a small electro-motor, one of the field magnets of which is shewn
by F, F, F, (the position of the armature being indicated by the dotted line).
Attached to the last wheel of the train is a plate p, p, p, similar to that of Figure 1. 1
revolving between the poles of the magnets m, m³, m, m,. The two intermediary
wheels b and c are mounted in the wheel e, f, which gears with a wheel g keyed to
the vertical shaft 8, 8, The rotation of this shaft regulates the arc and for this
purpose it has cut upon it a right and left handed thread for increasing and
decreasing the length of the arc in a precisely similar manner to that at present
employed in hand lamps. Keyed to the driving axis is a wheel h, h, gearing with
i, i, which latter is keyed to a shaft (shewn by the dotted lines) carrying at its
upper end J, J, in gear with k, k,. This last wheel k, k, runs at a much
higher speed then the wheel d, d, and is provided with a clutch L L so
that it may be put into and out of gear by means of the lever n, n,
furnished with an armature o, When the magnets m, m³, m¹¹, m¹¹ are
current flowing
excited by the main-current and the motor is driven by a
through a shunt circuit, the action of the lamp is as follows. Upon the current
being switched on it will flow through the motor and cause its armature to rotate,
but the magnets m, m³, m¹¹, ml will not be excited as the continuity of the
circuit is broken by the carbon electrodes being apart, as they were when the lamp
was last extinguished. There being no attraction between the armature o and the
pole of m¹ the lever n remains in the position shewn, and the wheel k, k, drives p P
and with it the last wheel of the train at a much greater speed than (d d) the
first. Consequent upon this the wheels b, and c, together with e, f, and g, are
driven round and the shaft s. 8. is made to rotate, which motion brings the carbons
into contact. The instant this takes place m³, m², m³, m³, are excited, the
armature o, attracted and k, k, thrown out of gear with p. p. The effect of this is
to instantly reduce the speed of p. p. (since it is not now driven by k, k, and it
experiences resistance to rotation due to its revolving in the magnetic fields m, m³,
m, m). This reduction in the speed of p, p, causes the shaft 8, 8, to revolve in
the opposite direction thereby separating the Carbons, The distance to which they
are separated being dependant upon the resistance offered to the rotation of p. p.
which may be varied by approaching or withdrawing the poles of the magnets.
When from the consumption of the electrodes, the are becomes longer (its resistance
thereby being increased) and the amount of current flowing slightly decreased)
p, p, will revolve faster which causes the Carbons to approach. In this way the
arc is continuously regulated. It is sometimes advantageous to employ a break
instead of the magnets m, m³, m", m¹¹, and in some cases I vary the speed directly
by greasing not employing the disc p, p, at all. It is advantageous to provide the
motor with a heavy fly wheel in order to render its velocity as constant as possible,
and in cases where great sensibility is required I regulate the velocity by means of
a conical pendulum. Figure 7, Sheet 5 shows diagrammatically a method of
adapting a conical pendulum to the plate p, p, 8, 8, is the shaft by which motion is
imparted to the train, but instead of being rigidly connected to the train it imparts
motion to the latter through the intervention of the magnetic lines of force of a
permanent or electro magnet +. The plate p, p, may therefore be instantly
brought to rest by a break acting upon it (or other means) and instantly set in
motion without varying the speed of a. Some of the advantages of this method of
regulating the mechanism are that sensibility of action is preserved although the
mechanism carbon holders &c. have necessarily to be made much larger and heavier
to suit the requirements of the more powerful currents, larger carbons &c, that it
-

page_text: will work in any position, that it is not affected by the rolling of a vessel or by
any sudden shocks &c. &c. In cases where it is necessary to exhibit the light for
periods of time longer than that required for the consumption of the carbon rods,
multiple carbon lamps are employed. It has been the practice hitherto to allow
the Carbons not in use to be in contact. The objection to this plan is that in
certain positions the light is occulted and shadows are cast by the rods not in use.
I obviate this difficulty by keeping the rods not in use apart until the ones in use
are consumed when they are allowed to come together, and when desirable (as
when more than two pairs are employed) I cause the approach of the new.Carbons
to separate the old ones. Figures 4 and 5 sheet 2 shew methods of carrying this
into effect. Figure 4 shews three carbon holder rods a, b, c, arranged so that the
Carbons not in use are kept apart until the preceding ones are consumed. The
pinions with which the rods a, b, c gear are shewn by p, p, p, p, each succeeding
pinion being connected to the preceding one by a ratchet wheel w, and
"click r
Each preceding pinion is therefore free to revolve without driving
the succeeding ones whilst the motion of any succeeding one is imparted to
the preceding ones. In the figure the rod a has descended nearly to the
bottom of its stroke on account of the carbon which it carries being nearly
consumed whilst b, and c, are held up out of the way by the levers l. 1. Upon
the rod a continuing to descend the lower extremity of lever is pressed
aside by the action of the collar c, c, upon the incline plane d. The effect
of this is to disengage the top of the lever l. from the collar e. e. The rod b is now
fed forward by the action of the feed mechanism as well as a. The teeth upon the
rods are not cut quite up to the collars c. c. &c. but only to the point f (shown by
the dot and dash line) figure 4a, which is an end view of figure 4. (It is often more
convenient not to employ teeth but to allow the rods to gear by friction only, in
this case a recess is formed upon the rods above the point f which has the same
effect as the discontinuity of the teeth when the latter are employed). Consequently
when the feed of a has been continued a little farther its teeth come out of gear
with p, and it rests by its collar upon the stop s. Directly the arc becomes longer
than its normal length (that is the length of are the mechanism has been set to
maintain) the rod b runs down and forms a new are between the next pair of
carbons. The resistance in the new circuit at the moment of contact of the
electrodes being so much below that of the arc in the preceding one, the former
are is extinguished. In this way the arc may be transferred from one to any
number of pairs of carbons as they are consumed with out the light being
extinguished. When (as bereinbefore mentioned) it is advisable to withdraw the
rods the carbons of which have been consumed the modification shown in figure 5
may be employed. In this case the pinion p is continuous and the racks instead
of being set all on one side of it (as in figure 4) are placed alternately on the one and
the other side (as in figure 5).
Upon the carbon being consumed the succeeding rod is disengaged as before
explained, but the rod a does not come out of gear with p, and the rod b does not
gear with the pinion until it has been released. The falling of braises a out of
the way. It is sometimes necessary (as for example where more than two pairs
of carbons are employed) to take the rods (which have returned to their original
position as shown by the dotted lines) out of gear with the pinion. The quadrant
and weighted lever shewn forms a very convenient method of doing this. The
action is as follows. The rods have cut upon them a short length of teeth in
addition to the main teeth as shown by the dot and dash line on a.
When the
rod has risen to the point p. it engages with the lever . the movement of which
brings the teeth on the quadrant into gear with those upon the rod, and continued
motion carries the weight w to the other side of a vertical plane passing through
its axis, and when the lowest tooth of the rod has become disengaged from the
pinion p, the weight w raises the rod until it comes into contact with the stop x.
Figure 6 shows a method of preventing shadows being cast from the lower carbons.
The carbon holder H is placed within a tube t, t, t', t¹. When the carbon has

page_text: been inserted H is pressed down against the pressure of a spring or weight, and
held in position by the detent d. When one of the succeeding carbons begins
to fall the detent is withdrawn by suitable means and the holder (together with
the carbon) rises until it comes into contact with the stops t¹. t¹. if the lamp
is not focus-keeping the tube may be fixed in any convenient way, if however
the lamp is focus-keeping the tube is attached to the lower carbon rack. The
high efficiency of the electric are (as compared with other systems of illumination)
is due to its power of concentrating a large amount of heat energy into a small
space. In order to further increase its efficiency I place in or around the arc or in
both positions a mass or masses of very refractory material such as lime. The
effect of this is to decrease the amount of heat lost by radiation to increase
the light by the incandescence of the substance, and to render the light more
steady. When placed around the arc the refractory substance may be in the
form of a block or ring provided with a hole just large enough for the carbon
to pass, when placed in the arc it may very conveniently be made in the
form of a rod, and one or both of the carbons being made hollow, the
rod or rods is or are placed inside thereof. In some cases I cause blocks
of refractory material to regulate the feed of the carbons in which cases
the feed mechanism is not required it being merely necessary to provide
for the formation of the arc.
I am
aware that electric arc lamps have
been constructed in which both carbons have been supported in a block
of refractory material but as the insulating capability of an insulator diminishes
inversely with the temperature upon the block becoming hot and portions of it
incandescent great loss of energy takes place, such however is not the case when
the insulator does not connect the carbons as in my arrangement. Figure 7. Sheet 2
shows a method of carrying it into effect. The carbon rod c. c. is supported by
its lower end in a block of refractory material m. m. (such as lime moulded into
form under great pressure) This block is attached to a plunger p. p. pl. p¹. the
attachment being very conveniently made by means of a bayonet joint between
the socket 8. 8. 8. 8. and the plunger, so that the block may be quickly removed
and renewed, When the lamp is not required to work differentially the arc may
be formed and its length regulated by the solenoid a. a. If required to be
differential both a shunt and main solenoid may be used, and the plunger arranged
as shown in dotted lines, or the solenoid a. a. may be both main and shunt wound.
The lower carbon may be controlled in a similar manner being forced up to the
block by any suitable means. In ordinary illumination it is generally required to
uniformly illuminate a certain ground or floor area for which purpose all rays
emitted by the are having an upward or horizontal direction are useless. The
distribution of light from the arc produced by unindirectional currents is far from
uniform. The greater portion of the light is emitted by the crater formed in the
positive carbon which would illuminate a horizontal plane below it with tolerable
uniformity, were it not that the negative carbon greatly obscures the light and
renders the central portion of the horizontal plane far less intensely illuminated
than segmental portions more remote from the centre, the greater the elevation of
the light the more pronounced is this defect. In order to obviate this and also to
utilize the rays proceeding in and above a horizontal plane passing through the
arc, I place around the arc total reflection prisms having angles such that rays
originally having an horizontal and upward direction are turned downwards and
made to illuminate the otherwise less intensely illuminated portion afore mentioned.
Figure 8. Sheet 2 shows an arc with an annular total reflection prism surrounding
it (the prism being in section) By curving the side a. a. of the prism any desired
distribution of light in a horizontal plane below may be obtained. In order to
reduce the cost of manufacture of prisms for use with powerful arcs (where it is
necessary to keep them a considerable distance from the arc in order to avoid
fracture from the heat radiated) I forn them hollow (preferably of sheet glass) and
fill them with liquid.
Having described and particularly ascertained the nature of my said invention

page_text: and shown modes and manners in which the same may be carried into effect, I
wish it to be understood that what I consider to be novel and original and
therefore claim as the invention secured to me by the hereinbefore in part recited
Letters Patent is :-
First In dynamo-electric generators and electro-dynamic machines the employ-
ment of armatures in the form of hollow chambers the sides of which are not
continuous, substantially as described and for the purposes specified.
Second. In dynamo electric generators and electro-dynamic machines indenting
or corrugating the surface of the armature substantially as described and for the
purposes specified.
Third In dynamo-electric generators and electro-dynamic machines the employ-
ment of field magnets, having hollow cores, the sides of which are discontinuous.
Fourth In dynamo-electric generators and electro-dynamic machines the forms
and methods of construction of armatures substantially as described.
Fifth-In dynamo-electric generators and electro-dynamic machines the methods
of arranging the conductor upon, and attaching it to the armatures substantially as
described.
Sixth-In dynamo-electric generators and electro-dynamic machines the method
of concentrating and intensifying the magnetic field (or fields) of force by the
employment of iron sheathing upon the field magnets.
Seventh-In dynamo-electric generators and electro-dynamic machines wherein
several or a number of field magnets are employed, arranging the conductor so
that each side of it is utilized in inducing the required polarity in the field magnets
substantially as described with reference to figure 2. sheet 1 of the accompanying
drawings.
Eighth In dynamo-electric generators the method of obtaining a constant
e. m. f. or constant strength of current at a constant speed by setting apart a
certain length of the conductor upon the armature for the production of an initial
and independent field of force, employed in conjunction with the field. of force
produced by the current circulating in the main or a shunt circuit.
Ninth In dynamo-electric generators and electro-dynamic machines the form*
and arrangement of commutator, and the method of collecting or preserving
contact substantially as described and for the purposes specified.
Tenth Governing electrical energy by the differential velocity of a body or
bodies moving under the control of the electric energy, and of another or others.
moving with a constant (or approximately constant) velocity or by variations in
the work done by an epicyclic train.
Eleventh The method of regulating electrical energy by the employment of
electrical accumulators and a governor in conjunction with dynamo-electric or
electric-dynamic machines, substantially as described.
Twelfth The method of regulating electrical energy by the employment of
dynamo-electric generators or electro-dynamic machines having the conductor upon
their field magnets applied in sections in conjunction, with suitable governors or
regulators for coupling up the said sections according to the requirements of the
work circuit.
Thirteenth In apparatus for regulating electrical energy and the direction of
flow thereof, the employment of a delicately balanced or suspended permanent.
magnet or piece of paramagnetic substance polarized by induction substantially as
herein described with reference to figure I Sheet 3 of the accompanying drawings.
Fourteenth-In regulating electric energy the method of allowing a greater or
lesser number of elements of batteries, accumulators &. &. to be put into or taken
out of circuit without inconveniently large currents at the momentary short cir-
cuitings by the employment of a resistance common to all, in conjunction with
apparatus for throwing the same into and out of circuit.
Fifteenth-In regulating electrical energy the combination of the compound.
wheel and circular or volute shaped track actuated electro-mechanically substan-;
tially as described with reference to figure 1 Sheet 2 of the accompanying drawings.

page_text: Sixteenth-In regulating electrical energy the employment of an apparatus in
which the regulation is effected by the movement of a liquid substantially as
described with reference to figure 2. sheet 2 of the accompanying drawings.
Seventeenth-In apparatus for measuring and recording the amount of electrical
energy passing in a circuit in a given time, the employment of an apparatus one
portion of which moves with a constant velocity, and in which the ratio which the
velocity of the registering apparatus bears to this constant velocity is varied
according to the amount of electrical energy passing in the circuit by differential
gearing substantially as described.
Eighteenth-The forms of apparatus for registering the numbers of lamp-hours
& substantially as herein described.
Nineteenth In apparatus for measuring and recording the amount of electrical
energy which has flown through a circuit the employment of two or more electro-
dynamic machines performing any work which is proportional to the velocity, the
one (or some) being of low resistance driven by the main current and the other
(or others) of high resistance driven by a current which is proportional to the
difference of potentials at the ends of the circuit, the amount of electrical energy
passing in which is required to be known, or of an electro-dynamic machine having
two or more armatures the one (or some being wound with a conductor of low
resistance and the other (or others) of high resistance the magnetic field of force
being produced by both the main and shunt circuit currents, or of an electro-
dynamic machine having one or more armatures, in which both the armature (or
armatures) and the field magnets have both high and low resistance circuits.
Twentieth-The method of indicating and registering the speed of any moving
mechanism by showing and recording the ratio which its velocity bears at any
moment to that of other mechanism having a constant and known velocity
substantially as described in reference to figure 5 Sheet 5 of the accompanying
drawings.
Twenty-first-In electro-energy meters, the employment of an electro-dynamic
machine to give a constant velocity to a portion of the apparatus, the ratio which
the speed of the registering apparatus bears to the portion having a constant
velocity being varied either differentially or directly according to the amount of
electrical energy passing.
Twenty-second. In apparatus for measuring electro-motive force, or difference of
potentials, current strength, resistance, electrical energy &c., the employment of one
or more moveable electro inagnets or solenoids working under the action of one or
more controlling permanent, or electro-inagnets or solenoids.
Twenty-third The method of attaching the incandescing conductor of incan-
descence lamps to the conducting wires substantially as described.
Twenty fourth-The method of forming the stem of incandescence lamps with
contact pieces thereto attached substantially as described.
Twenty-fifth-The method of attaching incandescing lamps to the conductors
and fittings by means of springs and contact pieces substantially as described.
Twenty-sixth-The method of making the joint between electric conductors, and
the form of coupling for this purpose substantially as described.
Twenty-seventh-The method of making and preserving contact in the moveable
joints of the fittings substantially as described.
Twenty-eighth-The method of constructing switches for use with currents of
moderate strength, substantially as described.
Twenty-ninth-The methods of reducing the amount of sparking on breaking
contact in circuits conveying powerful currents substantially as described.
Thirtieth-The method of rendering electric lamps suitable for use in dangerous
positions, by placing them within an outer case and providing suitable means
whereby the current is immediately arrested whenever this outer casing sustains
any damage.
'
Thirty-first. In electric mining and other lamps provided with their own source

page_text: of energy, the method of obviating the necessity of opening any portion of them,
or of having any moveable material connection with their interior by acting
inductively upon suitable switches, or commutators in their interior.
Thirty-second-In controlling the regulating mechanism of electric lamps the
employment of one or more delicately balanced or suspended electro-magnets or
solenoids working under the action of permanent or electro-magnets or solenoids.
Thirty-third. In the regulating mechanism of electric lamps the employment of
an epicyclic train.
Thirty-fourth-Regulating the electric arc by the differential velocity of matter
moving under the control of the electric energy, and that of other matter having a
constant (or approximately constant) velocity.
Thirty-fifth-The method of avoiding the shadows usually cast by the carbons,
holders &c., in multiple carbon lamps, substantially as described.
Thirty-sixth Placing in or around (or in both positions) the electric are, very
refractory material substantially as described and for the purposes specified.
Thirty-seventh-Regulating the feed of the carbons of electric lamps by means
of blocks of refractory material, substantially as described.
Thirty-eighth-Utilizing the horizontal rays and those having an upward
direction emitted by the arc for the illumination of ground area by the use of total
reflection prisms placed around the arc.
In witness whereof I the said Alfred Richard Sennett have hereunto set
my hand and seal this thirteenth day of March in the year of our Lord
one thousand eight hundred and eighty three.