IMPROVEMENTS IN APPARATUS FOR ELECTRIC LIGHTING
Year: 1879

page_text: LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and
Company, Solicitors of Patents, of 67, Strand, in the City of Westminster,
Civil Engineer, for the Invention of "IMPROVEMENTS IN APPARATUS FOR
ELECTRIC LIGHTING." A communication from abroad by Charles F. Brush,
of Cleveland, State of Ohio, United States of America.
ealed the 29th July 1879, and dated the 11th March 1879.
PROVISIONAL SPECIFICATION filed by the said Herbert John Haddan at
the Office of the Commissioners of Patents on the 11th March 1879.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. "IMPROVEMENTS
IN APPARATUS FOR ELECTRIC LIGHTING." A communication from abroad by
Charles F. Brush, of Cleveland, State of Ohio, United States of America.
The Invention relates to the construction and regulation of electric lamps, and is
especially applicable where several lamps are placed in one circuit. It consists,
first, in providing the upper carbon point of an electric lamp with a mechanism
which alternately keeps it stationary and allows it to advance by gravity, while the
lower carbon is fed by the resultant force of magnetism caused by the passage of
electricity through a coil in the main circuit and a coil in a shunt or branch circuit.
The lower carbon holder may be attached to and surrounded by a core which is
movable under the predominating influence of magnetism caused by the main current
and the opposing action of adjustable springs, so that the springs bring the two
carbons in contact when there is no circuit, and the lower carbon is drawn back by
magnetism as soon as the circuit is established. The current supplied to the lamp
is divided into two branches, of which the main branch goes through the main coil
and the carbons forming the electric arc, while the subsidiary branch goes through
the second or adjusting coil in a direction opposite to the current in the main coil if
the two coils act upon the same core, increasing and decreasing with the resistance
of the main circuit, and in this way tending to keep the distance between the carbon
points constant. The upper carbon may be held stationary by a clamp or other
suitable device which releases the carbon so as to be fed by gravity as soon as the
lower carbon has reached its highest place, thereby acting upon the said mechanism.
Instead of magnetising the same core or the same horse shoe magnet which regulates
Dion R71

page_text: the feed of the carbons the two coils may act on separate parts of the lamp, the
main coil regulating only the feed of the lower carbon, while the adjusting or
subsidiary coil controls the mechanism for feeding the upper carbon by means
of a magnet which alternately arrests and releases the upper carbon holder according
to the length of the electric arc and the strength of the subsidiary circuit depending
therefrom. The main coil may even be entirely dispensed with, the lower carbon
being kept stationary, and the upper one fed by the adjusting coil. If the carbons
are placed horizontally the same principle for regulating may be applied by adopting
suitable intermediate mechanism.
The second part of the Invention is a device whereby any lamp placed in a circuit
with several lights is automatically extinguished as soon as the resistance in the said
lamp becomes too great, so as to prevent the extinction of all lamps in the circuit
when the regulator of one lamp fails to act. This is effected by affording a passage
for the current independent of the carbon points when the latter fail to move forward
through a coil of high resistance, the ends of which are connected to the main
circuit of the regulator at points on opposite sides of the electric arc, and which
under normal circumstances only receives a small share of the total current. This
branch receives a greater portion of the total current as soon as the distance between
the carbons, and therefore the resistance of the main circuit, increases, until at last,
when the electric arc ceases, the branch forms the only channel for the current. In
this case the coil acts sufficiently upon an iron core to attract an armature, which
by suitable connections establishes a free passage for the current independent of the
carbons. In order to prevent the armature from falling back as soon as this short
circuit is established the latter forms a coil round the iron core which supplants the
first coil as soon as the latter ceases to conduct the current. The whole device may
be combined with and form a part of an electric light regulator, or it may be con-
structed as a separate mechanism, and instead of two coils and a core several cores
may be employed. In order to maintain the armature in its place residual magnetism
may be utilized instead of a coil formed by the short circuit. The lamps may
advantageously be suspended from the ceiling, on which there are a number of
contact surfaces arranged in pairs at any desired place.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Herbert John Haddan in the Great Seal Patent Office on the 21st
August 1879.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. " IMPROVE-
MENTS IN APPARATUS FOR ELECTRIC LIGHTING." A communication from abroad by
Charles F. Brush, of Cleveland, State of Ohio, United States of America.
The Invention relates to improvements in electric lamps or light regulators, and
in describing said Invention I will separate this Specification into two divisions.
In the Drawings, Figure 1, Division 1, represents a vertical section of an electric
light regulator embodying the Invention; Figure 2, Division 1, shows a modified
arrangement of releasing mechanism and clutch G, H; Figure 3, Division 1, shows
modified arrangement of principal helix A, and adjusting helix I; Figure 4,
Division 1, shows another modification of the same; Figure 5, Division 1, shows
one method of applying the adjusting helix I to an ordinary magnet such as is
involved in many regulators in common use; Figure 6, Division 1, shows the
adjusting helix I as used without a principal helix; Figure 7, Division 1, shows
a inodification of the same; Figure 8, Division 1, shows the adjusting helix and
principal helix operating different cores. Referring now especially to Division 1,
I will proceed to describe the device there referred to. In Figure 1, K is a base of
suitable material to which is attached a metallic post E supporting the arm X
which carries the rod B. This rod moves through holes in the arm X, and has at
its lower end a carbon holder which clamps the carbon F firmly in position so that
it is carried up and down with the rod; H is a ring clamp surrounding the rod B,
and prolonged and weighted at one side, as shewn. This clamp is supported on pro-
jections e attached to the arm X; l is a tube loosely surrounding the rod B for the
purpose of preventing the clamp H being carried up with the rod B when the
latter is raised; D is an iron core rigidly attached to the tube M, which projecting
above and below the core passes through suitable bearings, as shown, and terminates
above in the carbon holder L' which clamps the carbon F₁, the latter extending down
the tube M as far as may be desirable. c are arms attached to the upper end of the
core D by means of which the spiral springs C support and force upward the core D
and with it the carbon F; c' are adjusting screws for regulating the tension of the
springs C; G is an arm carried by the carbon holder L', and its upper end passes
loosely through a hole in the prolonged end of the clamp H. This clamp is pro-
vided at its end with an insulating material m so that the arın G cannot make
electrical contact with it. The arm Ğ is provided with an adjustable collar n so
placed that when the core D is at the limit of its upward movement the end of the
clamp H will be slightly raised. The lower portion of the core D is eur-
rounded by a helix of coarse wire A having one of its ends attached to
the binding post N and the other in connection with the carbon holder L¹
through the tube M and its upper bearing, as shown. P is a binding post
attached to the post E. When the regulator is not in operation the springs C
will force the core D upward, the collar n on the arm G will raise the end
of the clamp H, the rod B will be released, and will fall until the carbons F, F¹,
are in contact. The arm X being provided with a slot through which
the post E passes, the carbons F, F, may be adjusted in proper apposition
by loosening the nut j, which may then be tightened. The operation of the device
as far as described is as follows:- The posts P, N, being attached to a suitable
source of electricity the current passes through the post E, arm X, and rod B, to
the carbon F, thence through the carbon F¹, tube M, and helix A, to the other
binding post N. Under these conditions the core D is drawn down by the axial
magnetisin of the helix A, carrying with it the carbon F and arm G. The weighted
end of the clamp H being thus allowed to fall at the beginning of the downward
movement, the sides, of the hole in the clamp through which the rod B passes.

page_text: impinge against the latter, prevent its downward movement. The core D con-
tinuing to move downward separates the carbons F, F¹, and the voltaic arc is
developed between them, thus producing the electric light. The tension of the
spring C is so adjusted that the downward movement of the core D will be arrested
when the carbons F, F¹, are sufficiently separated, the magnetism of the helix A
being much reduced by the weakening of the electric current due to the resistance
of the arc between the carbons. Now as the carbons gradually burn away, their
distance from each other is increased, the electric current is weakened owing to the
increased resistance, and the magnetism of the helix A is reduced, so as to be over-
come by the spring C. This allows the carbon F' to move upward until sufficiently
near its neighbor, when it is stopped by the increased electric current acting on
the core D. When the carbons have burned to such an extent that the core D
approaches near to the limit of its upward movement the clamp H is raised, and the
rod B being liberated falls downward, carrying with it the carbon F until the
downward movement of the core D, caused by the shortening of the voltaic arc,
allows the clamp H to again fasten the rod B. By means of this simple device an
electric light may be uniformly maintained for many hours, the only limit to the
time being the length of carbon rods employed. The releasing arm G, Figure 1,
may be replaced by the arrangement shown in Figure 2, consisting of a lever g
pivoted at one end to the post E and connected by a link G with the clutch or
clamp H.
One end of the lever g projects over the carbon holder L', from which
it is insulated by suitable material h, as shown. The lever g and link G are so
arranged that when the carbon holder L' is at its upper limit the lever will be
raised by it, thus raising the clamp H and liberating the rod B. Obviously many
forms of clamps H and releasing mechanism G may be employed, the essential
elements being such as will release the rod B when the core D approaches near to
its upward limit, and clamp it when the core moves in the opposite direction. In
case it becomes desirable to operate this regulator in other positions than the
vertical one shown it will only be necessary to so arrange matters that gravity, or
suitable springs, or both, may produce the same movements of the several parts
which gravity and the springs C produce in the vertical position described. We
have now to consider the second important element of this Invention, which con-
sists in the introduction of the second helix I, used alone or in connection with the
principal helix A. I have styled the second helix the "adjusting helix," and will.
so refer to it in my description. It is employed for the purpose of governing the
automatic adjustments of the regulator, its value for this purpose being more
apparent when two or more are used in a single electric circuit. It it well known
that when an attempt is made to use two or more regulators of ordinary forms in
a single electric circuit they work very irregularly, some allowing their carbons to
come and remain in contact while others have their carbons widely separated. The
cause of this irregularity may be explained as follows:-Supposing two regulators
are being used at the commencement of the operation the regulators may start
evenly, especially if a limit is fixed to the separation of their carbons. When how-
ever the carbons burn away so that the weakened current allows them to move
toward each other this movement will commence in one regulator before it does in
the other, as it is impossible to adjust the regulators so nicely that their automatic
adjustments will take place simultaneously. But as soon as one pair of carbons
approach each other the electric current is strengthened, and the other pair of
carbons which were about to move forward will be retained in their old position.
When another adjustment becomes necessary the same regulator which proved the
more sensitive in the first instance may again advance its carbons first. These
operations are liable to continue until the more sensitive regulator has its carbons in
contact and ceases to afford light, while the other monopolizes the whole voltaic arc,
which was at first divided between the two. Hence it appears that no more than
one regulator of the ordinary forms can be successfully operated by a single circuit.
If however a device can be applied to the regulators above considered, which shall
automatically tend to force the carbons together with a constantly increasing pressure

page_text: as their distance increases, then the two regulators, or as many more as the current
is capable of operating, will work uniformly, each maintaining its due portion of
the voltaic arc.
This important result I attain by means of the adjusting helix I.
This helix consists of wire very much finer than that of the helix A, and con-
sequently the wire is much longer and makes more convolutions than the latter.
The ends of the fine wire are connected with the binding posts P and N, but in such
a manner that the electric current shall pass through it in a direction opposite to
that in the helix A. I will now be seen that the electric current has two passages
provided for it, one of high resistance through the adjusting helix I, and the other
of comparatively low resistance through the belix A, carbons F, F, and the voltaic
are between them. It is well known than when an electric current has two channels
for its passage it will divide itself between them, the relative amounts passing
through them being inversely as their resistance, hence any increase in the resistance
of one conductor produces a corresponding increase of current in the other. It
follows from the difference in direction of the current in the two helices that the
helix I will constantly tend to neutralize the magnetism produced by the helix A
in the core D, and thus diminish the force which draws the latter downward. The
number of convolutions of the helix I and its resistance are so proportioned to the
number of convolutions in the helix A and its resistance, together with that of the
normal voltaic are, that the magnetizing power of the latter helix shall be much
greater than that of the former. The magnetizing power of the former is however
very considerable, notwithstanding the small amount of current which passes through
it, owing to its great number of convolutions. Suppose now that two or more
regulators provided with adjusting helices are introduced into a single suitable
electric circuit the preponderant magnetism of the helix A will operate to separate
the carbons in the several regulators, as before explained, and the neutralizing effect.
of the adjusting helices I will be equal in all, thus performing no function as long.
as the regulators work uniformly; but when any irregulartity of action commences.
by which one pair of carbons are separated more than their normal distance then'
owing to the increased resistance of the main circuit in this particular regulator the
current in its adjusting helix is increased, thus further neutralizing the effect of the
principal belix and allowing the springs C to push the carbons back to their normal
position. If the carbons in any instance approach too near together the diminished
resistance of the main circuit in this instance weakens the current through the.
adjusting helix, allowing the principal helix to separate the carbons to their normal
distance. Thus it may be seen that the use of this simple device obviates all the
difficulties hitherto experienced in multiplying electric lights from a single source of
electricity. The adjusting helix I may occupy various positions in relation to the
principal helix A without interfering with its peculiar function; thus, for instance,
it may be placed within the principal helix instead of at either end, or it may be
placed outside of the latter. These modifications are shown respectively in Figures 3
and 4. The adjusting helix is equally applicable to those regulators in which an
ordinary electric-magnet is employed having its helix or helixes rigidly attached to
its core or cores; one method of so applying it is shown in Figure 5. Or it may
be applied to those regulators having two principal helices like the well known
"Browning" and similar regulators. It is of course equally applicable to single
principal helix regulators other than that represented in Figure 1, such, for example,
as that described in a former application of my own.
When a single regulator is
used in our electric circuit the adjusting helix acts as a valuable governor, preventing
sudden changes of position in the carbons and insuring great uniformity of working.
We have yet to consider the application of the adjusting helix to those regulators.
in which it may replace the principal helix entirely while still performing its"
peculiar function. Such a regulator is shown in Figure 6, in which the carbon F1
is stationary, being connected directly with the binding post N. The adjusting.
helix I here acts on an iron core p attached to the outer end of the clamp H and
taking the place of the weight similarly placed in Figure 1. One end of the adjusting
helix is attached to the binding post P through the post..E, while the other is

page_text: •
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attached to the binding post N. The operation of the device is as follows:-The
electric current being supplied to the binding posts P, N, the carbons are properly.
separated by raising the rod B. The electric current then divides itself between
the main circuit of the regulator including the carbons F, F1, and that of the.
adjusting helix, as before explained. When now the carbons burn away so that
their separation becomes too great the increased resistance of the main circuit
strengthens the current of the adjusting helix so as to enable it to lift the core p..
and with it the clamp H, thus allowing the rod B to move downward until the
decreasing resistance of the main circuit again allows the core p to fall and clamp
the rod B. Figure 7 shows a modified application of the adjusting helix as applied
to the regulator just described. Here the helix I and the core p, Figure 6, are
replaced by an ordinary electro magnet wound with the adjusting helix or
helices, and acting on an armature of iron attached to the clamp H, as shown.
Figure 8 shows a modification or development of the regulator represented
in Figure 6. In this case the lower carbon F' is operated by a principal'
helix A, in the manner described in connection with Figure 1, while the
mechanism for releasing the rod B is operated by the adjusting helix I, as
described in connection with Figure 6. We have here the principal helix A.
and the adjusting helix I performing their several characteristic functions
although separated from each other, and operating upon different cores or
magnets. Coming now to the consideration of the second division of this Inven-
tion, it consists in a system wherein two or more electric lamps or regulators are
placed in a single circuit with "short circuiting" contrivances connected with each
lamp or regulator, the whole being so arranged and adjusted that any lamp offering
too great an electrical resistance shall automatically close a shunt circuit whereby
said lamp shall be extinguished; also in the combination with an electric lamp of
any suitable shunt circuiting mechanism adapted to automatically close a shunt
circuit and extinguish any lamp wherein there is a too great electrical resistance
offered by said lamp; also in a peculiar construction and arrangement of contact
surfaces of lamp, and source of electric current, whereby any lamp is placed in
circuit by the simple act of fixing it at a locality where said lamp is intended to be
used. When several electric light regulators are operated by a single electric
current it is evident that the failure of any one of the regulators to feed its carbons
forward will by ultimately interrupting the current not only extinguish itself, but
also the lights of all the other regulators. It is to guard against this accident that
the present Invention has been designed. The device operates to close the electric
circuit through the regulator by affording a passage for the current independent of
the carbon points when the latter fail to move forward properly. This "short
circuiting" may be made to occur either before or after the interruption of the
current by the too great separation of the carbons. This design is accomplished by
shunting from the main current that passes through the regulator a small portion
of said main current by means of a helix of suitable high resistance. The ends of
this helix are connected to the main circuit of the regulator at points on opposite
sides of the voltaic arc; hence, as is well known, the amount of current through
this helix must vary with the resistance of said voltaic arc. If now the regulator
to which this helix is applied fails to advance its carbons their increasing separation
due to their combustion or other cause will constantly increase the resistance of the
voltaic arc, and thus shunt more and more of the whole current through the helix,
whose resistance remains constant. This action may continue until the voltaic arc
finally ceases, in which case the resisting helix affording the only circuit through the
regulator may convey even more current than before the cessation of the arc. I
inclose within the helix a core of iron, and place near the lower end of this core an
armature at such a distance that the magnetism of the core induced by the current
in the helix shall be insufficient to raise it when the normal amount of current is
passing through the helix, but when owing to the too great separation of the
carbons in the regulator or the cessation of the voltaic arc this current increases
beyond a certain strength the armature is attracted and drawn toward the core,

page_text: thus making a contact between suitable metallic surfaces suitably connected, and
affording a free passage for the current through or around the regulator independent
of the carbons. But it will be obvious that when the device has operated as just
described, the current will be greatly lessened in the said helix, and consequently
without some retaining device the armature would fall back in its old position,
thus opening the electric circuit. Residual magnetism may be utilized for this
purpose, and a number of mechanical devices also readily suggest themselves; but
for this purpose the device shown in the Drawings is preferred. It consists of the
second belix of coarse wire surrounding the core, which helix forms part of the
"short circuit" which is established when the core lifts the armature. This helix
coming into action at the instant when the helix of high resistance before described
ceases to be efficient maintains the magnetism of the core (and consequently the
integrity of the "short circuit") until the faulty regulator is removed or the current
stopped. My whole device may be combined with and form a part of an electric
light regulator, as shown in the Drawings, or it may be constructed as a separate
piece of mechanism, and applied to any regulator, either near or at a distance by
means of suitable conducting wires. Two cores may be employed instead of one,
as described, thus forming an ordinary horse shoe electro-magnet, and the two
helices described (or more than one of each) may be arranged in many obvious
ways in relation to each other, while still performing their peculiar functions, or the
second helix of coarse wire may be dispensed with as above indicated. In the
Drawings, Figure 1, Division 2, shows one form of device embodying the Invention,
and one method of placing several lamps on a single circuit; also one method of
attaching a pendant lamp to a ceiling. Figure 2, Division 2, shows a few of various
modifications to which my Invention is susceptible as relates to the method of
attaching a lamp to a wall or ceiling. Figure 3, Division 2, shows a few of various
modifications to which my Invention is susceptible as regards mechanism for
automatically accomplishing the shunting or short circuiting hereinbefore mentioned.
The form in which I shall describe the Invention is that of the pendent or swinging
lamp, which, as appears in United States Patent, No. 203,411, granted to the
Inventor May 7th, 1878, is but one of several varieties. But I wish it to be under-
stood that the application of the present Invention is not limited to any specific
form of lamp or regulator whatever, inasmuch as it may be adaptable without any
material variation to electric light regulators of many kinds other than those which
are shown. A is a plate of wood, gutta percha, or any other suitable non-conducting
material; to this plate are attached the suspending hooks, loops, or their equivalent A
These hooks are simply designed to suspend the lamp, and are not placed in electrical
connection with any part of the apparatus. A2 are loops or hooks attached to the
wall or ceiling with which the hooks A' engage; B, B, are contact plates, springs,
or their equivalents representing and placed in electrical connection respectively.
with the positive and negative poles of the lamp; B¹, B', are stationary plates,
springs, or other suitable equivalent contact surfaces fixed stationary at that locality
in the wall or ceiling where the lamp is intended to be used. These contact
surfaces B' represent and are placed respectively in electrical connection with the
battery, dynamo-electric machine, or other source of electric current. The contact
surfaces B and B¹ may be constructed in any manner, so that by the act of placing
the lamp in position they shall be brought together in such a way that the lamp is
put in the electric circuit. I do not limit myself to any special design or con-
struction of the contact surfaces B, B', as they may be indefinitely varied without
in any degree departing from the Invention; C is a frame preferably constructed
of iron or other electro-conducting material, and this frame is formed in any proper
manner to hold and accommodate the various parts of the regulator; D is the
magnet-core, herein before described; D¹ is the armature; around the magnet core
is wound the helix E of coarse wire, and the helix Ei of fine wire. It will be
observed that the armature is made movable by pivoting it to the frame C. The
arinature and frame C are placed in electrical connection with each other. The
position of the armature D' during the time that the lamp is properly acting is in.

page_text: its dropped position away from the core D. The distance of the armature drop
may be regulated in any desired way by means of the curved piece F, which may
be hent at pleasure to adjust the desired drop of the armature. The piece F rests
upon any suitable stop F¹; G is a contact point of any suitable conducting material
so placed that the armature as it is lifted will impinge against it before coming
into contact with the core D, thus always preventing any actual union between the
core and armature. This contact point G connects with the coarse wire helix E.
The coarse helix is arranged and connected as follows:-Commencing from the
contact plate B, it describes a helix around the core D, and terminates with the
contact point G. Thus it will be seen that until connection is made between
the contact point G and armature D¹, the coarse helix E does not constitute any
part of a completed circuit. The fine wire helix E' commencing from its attach-
ment to the coarse wire, as shewn at c proceeds directly to describe a helix about
the core D, and then connects with the frame at c', and also with the pole B,
opposite from that to which the coarse helix E is primarily connected as above
specified. It is obvious that the device just specified is susceptible of an indefinite
number of modifications, for instance, instead of the magnet as described a horse-
shoe or two legged magnet may be used, one leg carrying the coarse wire, and the
other the fine wire helix, and the connections be made substantially as before
shown. Likewise the armature and its adjustment may be indefinately varied, as
indicated in the Drawings. During the time that the lamp is properly performing,
the current through the fine wire helix E' will not be sufficient to lift the.
armature D¹, but when it is desirable to "shunt circuit" the lamp, as above set
forth, then the current will be sufficiently strong to draw the armature. The
degree of strength of current required to lift the armature is determined entirely
by the adjustment of the armature, and this degree may be greater or less as
circumstances may require. It will be borne in mind that during the time the
armature is in its dropped position, the main portion of the current is passing
through the carbons; but when the armature is drawn into its contact position,
then the carbons are cut out of the electric circuit and the current takes the
following course :-Beginning from the pole B it passes down through coarse belix,
thus strongly magnetizing the core D (and thus securely maintaining a "contact
position" of the armature), then through the contact points G, and through the
armature D' to the frame C, and from thence to the opposite pole B with which the
frame C is now in electrical connection. Instead of constructing the magnet and
armature as shewn in the Drawings, these parts may be adapted to operate by the
force of axial magnetism. In such case the helix or helices E or E' are wound upon
a hollow spool within which extends a core attached to a lever similar to the
armature D¹. The attractive effect of the current in such a construction would be
to draw the core up within the hollow of the helix spool, thus to make a contact
between part G and frame C as already specified; what I claim is:-1. The com-
bination in a single circuit of two or more electric lights, each of which is provided
with an upper carbon point having mechanism connected therewith for releasing
the carbon holder, and allowing it to be fed by gravity, and a lower carbon the
position of which is regulated by the resultant force of axial magnetism caused by
the passage of electricity through a helix in the main circuit, and a helix in a shunt
circuit, substantially as shown in Division 1. 2. In an electric light regulator, the
combination with a carbon holder of a magnet surrounded by two helices, one helix
located in the main circuit, and the other in a shunt circuit, the main and
subsidiary currents passing through said helices in opposite directions, substantially
as shown in Division 1. 3. In an electric lamp, the combination with a movable
core supporting a carbon point, and upheld by suitable springs of a helix sur-
rounding the core and connected with the main circuit, and a superposed subsidiary
helix also surrounding the movable core and connected with a shunt circuit,
substantially as shown in Division 1. 4. In an electric lamp, the combination
with a movable core supporting one of the carbon points, and a main and subsidiary
helix surrounding said core, and respectively connected with main and shunt,

page_text: circuits of the upper carbon point, and suitable intervening mechanism whereby
the upper carbon point is fed downward by the action of the lower carbon point,
substantially as shown in Division 1. 5. In an electric lamp, the combination
with the upper and lower carbon points thereof of a helix in the main circuit, and
a helix in a shunt circuit, both of said helices surrounding a movable core with
which one of the carbon points is connected, and clamping mechanism connected
with the upper and lower carbon points, substantially as shown in Division 1.
6. In combination with an electric lamp, a suitable short circuiting device adapted
to automatically shunt the current from the lamp, when for any reason there is a
too great resistance offered by said lamp, substantially as shown in Division 2.
7. A system wherein two or more electric lamps or light regulators are placed in a
single electric circuit with short circuiting contrivances connected with each
said lamp or regulator, the whole being so arranged, constructed, adjusted, and
electrically connected that from any lamp or regulator offering too great a
resistance the current will be automatically shunted, substantially as shown in
Division 2. 8. The combination with each electric lamp on a single circuit
containing two or more of said lamps of a shunt and mechanism, substantially as
described, whereby any undue resistance in any lamp to the passage of the electric
current will operate to automatically shunt the current through such lamp's
individual shunt, thereby shunting the current from said lamp without permanently
extinguishing or materially affecting any other lamp in the circuit, substantially as
shown in Division 2. 9. An electro-magnet D having a fine-wire helix E¹, and a
coarse wire helix E combined substantially as specified, and adapted respectively
to shunt and to maintain shunted the current from an electric lamp with which it
is associated, substantially as shown in Division 2. 10. The combination with an
electric lamp of the electro magnet D and an armature D', said armature D' being
electrically connected in such a manner that when by reason of the lamp with
which it is associated offering too great a resistance to the electric current, it (the
said armature) shall be made to close a shunt circuit, thereby shunting the current
from said lamp, substantially as shown in Division 2. 11. Associated with an
electric lamp or regulator, the helix E' of comparatively high resistance adapted to
automatically operate a shunting device whenever said lamp or regulator shall
offer an abnormally great resistance to the current, substantially as shewn in
Division 2. 12. In combination with a suitable device for attaching an electric
lamp to a wall, ceiling, or support; one or more suitable contact surfaces B, B,
electrically connected with said lamp, and contact surfaces B¹, B', representing and
placed in electric connection respectively with the positive and negative poles of
the battery or other source of electric current, said contact surfaces B' placed
stationary at the locality where said lamp is intended to be used, substantially as
shown in Division 2.
In witness whereof, I, the said Herbert John Haddan, have hereunto set
T
AT 1970