IMPROVEMENTS ELECTRICAL LIGHTING APPARATUS.
Year: 1881

page_text: '
LETTERS PATENT to Paul Louis Marie Gadot, of Boulevard Saint-Denis, 1,
at Paris, Electrician Engineer, for an Invention of "IMPROVEMENTS IN
LETTERS PATENT to Paul Louis Marie Gadot, of Boulevard Saint-Denis, 1,
at Paris, Electrician Engineer, for an Invention of "IMPROVEMENTS
ELECTRICAL LIGHTING APPARATUS.'
IN
PROVISIONAL SPECIFICATION left by the said Paul Louis Marie Gadot
at the Office of the Commissioners of Patents on the 27th May 1881..
PAUL LOUIS MARIE GADOT, of Boulevard Saint-Denis, 1, at Paris, Electrician
Engineer. "IMPROVEMENTS IN ELECTRICAL LIGHTING APPARATUS."
In the various systems of electric lighting, and specially in that in which the so
called electric candles (Jablochkoff candles, for instance,) are used, comparatively
short carbons are employed, because of their resistance, fragility, and for other
reasons; these carbons are very rapidly consumed by the action of the voltaic arc of
incandescence, and the like, and consequently afford light of a rather limited
duration only; when the first candle is consumed the current has to be passed to a
second one; when this is used up, to a third one, and so on.
The apparatus which carries the candle is termed the lamp, and it carries as
many candles as are required for the period during which the illumination is
required to continue, a Jablochkoff candle being reckoned to last about 1/2 to 2
hours.
For the sake of greater clearness I shall, in this description, more particularly
refer to the system of lighting based upon the use of the Jablochkoff candle,
although this Invention is applicable to other systems also.
The passing of the electric current from one candle to another has hitherto been
effected by hand with the exception of a few not very successful attempts, and by
means of a commutator or switch the moveable contact piece of which is successively
placed by the person superintending the lighting upon the contact fixed-pieces,
each of which corresponds to one candle.
The change when made by hand entails considerable expense, whilst exposing
the lighting to various accidents arising from negligence and other causes.
In some systems of lighting there is a commutator or switch in proximity to
Do71

page_text: each lamp, or underneath the lamp itself, and at the moment of the change as
many operations of the attendant are consequently necessary as there are electric
burners; this arrangement of the circuit is termed "cross-circuit,” and the lamps
cross-circuit lamps."
<<
In other systems of lighting one commutator only is used for all the burners of
the same circuit, and consequently one operation only is necessary for effecting the
change in all the burners of the said circuit, these circuits and their lamps slightly
differ from the preceding ones and are called "circular."
There are moreover some mixed arrangements, which part resemble both the
preceding ones, and lastly, the simplest of all, the elementary circuit consisting of
one wire only, as for electric regulators.
The automatic lamp, which forms the subject of this Invention, is equally
applicable to all these arrangements, and is always the same, excepting a few very
simple adaptations to each case.
The arrangement for cross-circuit according to this Invention is as follows:-
For the sake of clearness I will proceed to describe a lamp with four candles.
It consists of an ordinary cross-circuit lamp, each of the candles being held between
two jaws or clamps, and these two jaws (which hold the same candle) together I
term a "couple." One of the jaws in each of the four couples is connected with a
terminal, common to all, which I designate as the "central terminal," although in
some arrangements (the one I am now describing especially) it is not placed in the
centre; the second or interior jaws are connected each with a separate terminal.
To this ordinary lamp I add,
(1.) To each interior jaw an expanding spring, consisting of two or more springs
which are expanded differently by heat, and such spring is analogous to those in
general use for numerous industrial purposes, as, for instance, in metallic thermo-
meters, in automatic heat regulators for dye baths, and so forth.
(2.) By the side of each couple I place a contact device having springs and being
in electric communication with the next interior jaw. (3.) An extinguisher in
this instance placed in the centre and communicating with the above mentioned
central terminal, and consequently with all the exterior jaws.
The operation is as follows:-
The expanding spring supports a piece forming part of the contact device which,
acted upon by the springs above mentioned, and also forming part of the contact
device, bears strongly against the interior jaw, thus placing the next interior jaw
and consequently the next candle in the electric circuit; two cases may then occur.
Either the next candle and its priming present less resistance than the candle
which is in operation and its voltaic arc, and in this case it will be ignited and the
desired purpose is attained.
Or the next candle and its priming present a greater resistance than the first
candle and its voltaic arc, and then this remains in operation, but the expanding
spring continues to expand and soon touches the extinguisher and also places the
first interior jaw in electric communication with the central terminal, and thus
completing the circuit, causes the candle which is in operation to be extinguished;
this when extinguished presents an enormous, or rather an insuperable resistance
to the current, and at the same time ceases to heat the expanding spring, which
leaves the extinguisher. No way then remains for the current but the next candle,
which is then compelled to ignite; all this takes place instantaneously.
In this explanation I have not taken into account the resistance offered by the
jaw terminals and other parts in the operation of this apparatus, which however
need not be considered and are practically the same for all the jaws.
It will be moreover clear that in a lamp of this construction the circuit may be
reduced to its simplest form and consists of a single wire, the two ends of which
are attached to the two poles of the electric machine, or of any other current
generator, and which passes through all the burners; and in each lamp there
would only be one terminal for the ingoing current and one for the out going one
together, therefore two terminals to which two wires are attached.

page_text: Accidents however, which it is impossible to foresee, may occur; for instance,
a violent shock upon the lamp may break the candle which happens to be
in operation, and which, by the particular state in which it is, perhaps, more
liable to break; or a candle, the carbons of which are badly made, or which is
effected by a too intense current, may be consumed irregularly, and such accident
may cause extinction, and it is important to be able to remedy this without the
necessity of replacing the candles or to effect a disengagement of the parts to put
the next candle in circuit. For circuits of long duration the cross circuit with its
switches may therefore be retained. In case of accident the moveable contact
piece of the switch is placed upon that fixed contact piece which corresponds to
that candle which follows the one which has broken or has been burning badly,
and the operation proceeds in the usual manner.
The contact pieces of the switch will have to be arranged in such order as to
correspond to the terminals of the lamp and in the direction in which the changes
take place so as to provide for accidents and avoid all uncertainty when occasion
offers for operating the said switches.
It will be observed that in a lamp of this kind there is not, properly speaking, a
first candle, and I can take any that may be desired to be the first, taking care for
the order of the others to follow the direction in which the automatic change takes
place, in an analogous manner; an arrangement, hereinafter described, may be adopted
for the switch in which there is no "dead point," and in this case that for the first
contact-piece any of those on the switch may be chosen.
To provide against any accident that may arise through an attendant neglecting
to stop the lighting, a case that might occur where a constantly working motor is
employed (a water wheel for instance), the contact device of the last candle (which
device need not necessarily exist, as the switching serves no absolutely necessary
purpose after the last candle) may be placed in communication with one end of a
resistance device of iron wire, German silver, or other solid or liquid substance, of
the same strength as a candle in operation; the other end of this resistance device
would be placed in communication with the terminal of the switch which is connected
with the central terminal of the lamp, so that the current will pass automatically
through this resistance device, after having consumed all the candles in the lamp.
Without affecting this arrangement, a fixed terminal may be reserved on the
switch, which corresponds to the aforesaid resistance device, which would allow &
burner to be rendered inactive at will, the others in the same circuit continuing to
operate. The whole resistance device above described may however be considerably
varied.
The lamp, which is termed a switch or commutator lamp (being only a lamp
embodying its switch), is only a particular form of that hereinbefore described, and
the same remarks will apply to it, and it may be provided with the same devices
either for the automatic changing or the operations I have just described as the
cross circuit lamp."
"
**
The construction for circular lamps is as follows:-
The lamp I have above described as arranged for a cross circuit" may also be
used, with slight modifications presently to be set forth, as a " circular lamp.
The only difference between an ordinary "circular" lamp and an ordinary
"cross-circuit" lamp is that in the latter each couple has one of its jaws or clamps
connected with one jaw of the other couples, and with a terminal termed a central
terminal, the other jaws being perfectly independent, and in a "circular" lamp;
all the jaws without exception are perfectly independent of one another, and each
has a terminal corresponding thereto.
This remark at once indicates the arrangement of an automatic "circular "
embodying my Invention. Such "circular" lamp I construct as follows:-
lamp
To cach interior jaw I add an expanding spring having the same effect as that
in the "cross-circuit" lamp.
By the side of each couple I place a contact device, having two springs, one of
which is in communication with the next exterior jaw and the other with the

page_text: interior jaw, that is to say, that of the same couple as the former one; the contact
piece is divided into two parts insulated from one another, and each connected
with its respective spring. The extinguisher is divided into as many insulated
parts as there are candles; these parts correspond each with the exterior jaw
opposite thereto, say by means of a wire.
Moreover where the contact with the interior jaw takes place one half of the
contact surface is in electrical communication with the exterior jaw, for instance,
by a metal band, and is insulated from the interior jaw which forms the other
half of the contact.
By referring to the explanation given with reference to the "cross-circuit " lamp,
the operation of this lamp will be easily understood. The consumed candle
heats the expanding spring which opens and becomes disengaged from the contact
piece, which impelled by its springs bears against the contact surface, and thus
brings the next two jaws, and consequently the next candle, within the electric
current, and either this candle ignites, the consumed candle is extinguished, and
the desired result is at once attained, or the consumed candle remains ignited, the
said spring continuing to expand touches the extinguisher, completes the current,
causing the candle to be extinguished. The expanding spring then being no
longer heated withdraws, and the next candle is then forced to ignite.
An elementary circuit suffices for the practice of the Invention; in this case as
well as in the former, that of the "cross circuit" lamp, the lamp has only two
terminals, one for the ingoing and one for the outgoing current.
But to provide for accidents the ordinary "circular" arrangement may be retained.
In this case the contact pieces of the switch will be made to correspond with the
terminals of the lamp in the precise direction of the automatic change, which will
have to be the same for all the lamps. In case of accident the change will be
effected by hand.
For the single switch of a circuit to be used for the last described form of lamp,
the arrangement already described with reference to the "cross-circuit" switch
may also be adopted.
"
In a manner analogous to that described with reference to the ". cross circuit
lamp, I can also arrange a resistance device for this form of lamp, providing for each
lamp a resistance device equivalent to one candle in operation, and into this
resistance the current passes when the last candle is consumed. A contact piece
may be reserved on the switch and communicate with the resistance device of
each lamp.
It will be seen that all these apparatus, those for the "cross-circuit" and others
operate on the same principles. The application of these principles may be
extended as already stated to all electrical systems, not only those with candles, in
which the current passes from one to the other, but equally to electric regulators
in which the current passes from one carbon to the other, in incandescent lamps
and the like, in general to all electric apparatus where it is necessary to change
the path of the current.
I would also remark that disengagement is not necessarily tied to extinction.
The disengagement may take place by an expanding spring acting either directly
or by means of small levers, and the extinguisher may also consist of a second
expanding spring, or of a kind of small reservoir containing mercury or water,
or any liquid, or of a solid body of greater or less resistance, communicating with a
pole which, when expanding by the influence of the current, touches a small
appendage connected with the other pole and thus completing the circuit.
The springs of the contact pieces themselves may in their movement when
disengaged cause a sufficient momentary extinction of the consumed candle, by
causing them to touch for a moment any two pieces which are in electrical con-
nection, the one with the exterior jaw, and the other with the interior jaw of the
consumed candle.
The extinction or completion of the circuit may take place either before, during,
or after the dis-engagement, without materially affecting the automatic action of

page_text: the whole, and this whether the same spring serves for the disengagement and the
extinguishing arrangement, or that the expanding spring serves for disengagement
only, and that altogether independent devices are adopted for the extinction.
The contact device, under the expanding spring which supports it, may be placed
in engagement either by hand or by the replacing of the consumed candles by
new ones, after the periods of lighting it is sufficient for this purpose to attach to
the spring of the exterior jaw (in my arrangement) or upon the moveable jaw
itself, a suitably arranged abutting piece, which, when the candle is taken out,
pushes against the springs of the contact device or the device itself, and engages
the same.
The contact surfaces may be covered with small metal studs, which, after the
disengagement, would take into one another and would thus cause more close
contact.
Lastly. I would observo that my apparatus is entirely independent of the
direction of the current, and that it can be applied to continuous or alternating
currents. I may moreover either embody all the devices above described in one
apparatus, or I may use one or more of them in connection with other forms of
apparatus or devices to which they are applicable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Paul Louis Maric Gadot in the Great Seal Patent Office on the
23rd November 1881.
PAUL LOUIS MARIE GADOT, of Boulevard Saint Denis, 1, at Paris, Electrician
Engineer. "IMPROVEMENTS IN ELECTRICAL LIGHTING APPARATUS."
In the various systems of electric lighting, and especially with the Jablochkoff
electric candles, comparatively short carbons are used on account of their resistance,
fragility, and other reasons; these carbons are very rapidly consumed by the action
of the voltaic arc of incandescence, and the like, and only afford light of a rather
limited duration, so that for a longer duration of lighting, when the first candle is
consumed, the current has to be passed to a second one, and when this is used up
to a third one, and so on.
The apparatus which carries the candles is termed the lamp, lantern, bracket, or
pendant, hereinafter called lamp only, and it carries as many candles as are required
for the period during which the lighting is to continue, a Jablochkoff candle being
reckoned to last about 1/2 to 2 hours.
For the sake of greater clearness, I shall in this description more particularly
refer to the system of lighting based upon the use of the Jablochkoff candle,
although my Invention is applicable in a general manner to other systems.
The passing of the electric current from one candle to another bas hitherto been
effected by hand, with the exception of a few not very successful attempts, and by
means of a commutator or switch, the moveable contact piece of which is succes-
sively placed by the person superintending the lighting upon the fixed contact pieces,
each of which corresponds to one candle.
This change as made by hand entails considerable expense, whilst exposing the
lighting to various accidents arising from negligence and other causes.
In some systems of lighting there is a commutator or switch in proximity to
each lamp, or underneath the lamp itself, and at the moment of the change as many
of the operations of the attendant are necessary as there are electric lights (foyers).
This arrangement of the circuit is termed "cross-circuit," and the lamps "cruciform
lamps."
In other systems of lighting one commutator only is used for all the lights of the
same circuit, and consequently one operation only is necessary for effecting the
change in all the lights of the same circuit. These circuits and their lamps differ
slightly from the preceding ones, and are called "circular."
There are moreover some mixed arrangements, which partly resemble both the
preceding ones; and, lastly, the simplest of all is the elementary circuit consisting
of only one wire, as for electric regulators.
My automatic lamp is equally applicable to all these arrangements, its operation
is always the same, with the exception of a few very simple adaptations to each
case.
The arrangement for cross-circuits according to this Invention is as follows:-
For the sake of clearness I will proceed to describe a lamp with four candles
(see Figs. 1, 2, 3, and 4). It consists of an ordinary "cruciform lamp," each
candle M being held between two clips, clamps, or jaws p and p¹, hereinafter, to
avoid repetition, called clip only, and these two clips (which hold the same candle)
together I term a "couple."
One clip of each of the four couples is connected with one and the same
terminal B, which I designate the "central terminal," although in certain arrange-
ments (and especially in the one I am now describing) it is not placed in the centre;
the second or inner clips are connected each with a separate terminal b, b, b, b.
To this ordinary lamp I add,-
1. To each inner clin an expanding spring D. consisting of ture or more snrinca.

page_text: which are expanded differentially by heat, analogous to those in general use for
numerous industrial purposes, as, for instance, in metallic thermometers, in automatic
heat regulators for dye baths, &c.
2. At the side of each couple a contact device G, having springs r, r, in electric
communication with the next inner clip.
3. An extinguisher E, placed in this instance in the centre of the lamp, and
communicating with the central terminal B, and consequently with all the outer
clips.
The working is as follows:-
The spring D engaged beforehand, as shewn in Figure 1, keeps the piece C out of
contact with the inner clip p¹. When the candle is on the point of going out, the
heat of the voltaic arc, of the incandescence of the carbons, &c., causes it to expand
by dilatation. In expanding it ceases to hold the piece C, which, acted upon by
its springs r, 7, bears strongly against the inner clip p¹, thus placing the next inner
clip, and consequently the next candle, in the electric circuit; two cases may then
occur :-
Either the next candle and its priming or lighting fuse present less resistance to
the candle in operation and to its voltaic arc; then it will be ignited, the candle in
operation will be extinguished, and the desired purpose attained.
Or else the next candle and its priming present a greater resistance than the first
candle and its voltaic arc, and then this remains in operation, but the spring D
continuing to expand soon touches the extinguisher E, and thus places the first
inner clip in electric communication with the central terminal B, and thus closing
the circuit causes the candle which is in operation to be extinguished. This candle
when extinguished presents an enormous, or rather an insuperable, resistance to
the current, and at the same time ceases to heat the expanding spring D which
leaves the extinguisher E. No way then remains for the current but the next
candle, which is then compelled to ignite. All this takes place as it were
instantaneously.
In this explanation I have not taken into account the resistance offered by the
clips, terminals, and other parts in the operation of this apparatus, which however
need not be considered, and are practically the same for all the clips.
I must here remark that I need not compel the current to pass through the
springs r, r; this would permit of their being made of any suitable material,
without regard to its capacities as an electric conductor, and in this case they need
not any longer be connected to the next inner clip. In such case I would place
between C and the inner clip in question a kind of flexible tongue electrically
connected with the next inner clip, which tongue at the moment of disengagement
would be strongly pushed against the next following inner clip, and would then
place the next inner clip in the direction of the current.
It has likewise to be remarked that the number of contacts established by the
disengagement, and through which the current has to flow, increases by units for
every candle in succession; still I can make such arrangements that even at the
3rd to the 4th candle, &c., the current may have to pass one only of these contacts.
For this purpose it is only necessary to unite either the springs in the one con-
struction, or the tongues in the other, to the inner clip of a candle, which should
always be the first to burn; but then the contact by disengagement would take
place, not with the inner clip in question, but with a surface electrically connected
with the next following outer clip.
It will be understood moreover that in a lamp of this construction the circuit
may be reduced to its most simple form, and consist of a single wire, the two ends
of which are attached to the two poles of the electric machine, or of any other
current generator, and which passes through all the lights, as shewn by the dotted
lines in Figure 5; in each lamp there would be only one terminal for the ingoing
current and one for the outgoing one, in all two terminals, and two wires attached
thereto.
Accidents, which it is impossible to foresee may however occur; for instance, a

page_text: violent shock to the lamp may break the candle which happens to be in operation,
and which by the particular state in which it is, is perhaps more liable to be
broken; or else a candle, that is, the carbons of which are badly made or affected
by a too intense current may be consumed in needle shape or irregularly, &c., such
accident may then cause an extinction, and it is important to be able to remedy
this without the necessity of replacing the candles, or effecting a disengagement of
the parts to put the next candle in circuit. For installations of duration, the
" cross circuit
with its commutators (Figure 5) may be substituted. In case
of accident the movable contact piece t of the commutator N is placed upon that of
the fixed contact piece v, v, v, corresponding to the candle.which follows the one
which had broken or had been burning badly, and the operation proceeds in the
usual manner.
"
In such case it would be necessary that the contact pieces of the commutator be
so arranged as to correspond (starting from the dead-point to the terminals of the
lamp) to the direction of the automatic change (Fig. 5), so as to provide against
accidents above mentioned, and to avoid all uncertainty.
It will be observed that in this lamp, as shewn in Figures 1, 2, 3, and 4, there is
not strictly speaking a first candle, and I can take as the first one any one that
may be desired, taking care for the order of the others to then follow the direction
of the automatic change; in an analogous manner the arrangement shewn in
Figures 6 and 7 may be adopted for the commutators in which there is no dead
point, and where it will also be observed that the first of the fixed contact
pieces v, v, may be indifferently chosen amongst those which constitute the
commutator.
To provide against any accident that may arise through an attendant neglecting
to stop the lighting, a case that might occur where a constantly working motor is
employed (a water wheel for instance), the contact device of the last candle (which
device need not necessarily exist, as the switching serves no purpose after the last
candle is consumed) may be placed in electric communication with one end x of a
resistance device R (Figure 8) of iron wire, German silver, or other solid or liquid
substance forming a resistance equivalent to that which is presented by a candle in
operation, the other end of this resistance device R would be placed in communi-
cation with the terminal g of the commutator N which is connected with the
central terminal B of the lamp, so that the current will pass automatically through
this resistance device after having consumed all the candles in the lamp.
Without affecting the foregoing arrangements a fixed contact piece h corre-
sponding to the aforesaid resistance device may, if desired, be reserved on the
commutator, which would allow a light to be rendered inactive at will, the others
in the same circuit continuing to operate. The whole arrangement of the resistance
device following that just described, which is indicated at Fig. 8, may however be
considerably varied.
The lamp which is termed a commutator lamp (being only a lamp embodying a
commutator) is only a particular form of that herein before described, and the same
remarks will apply to it, and it may be provided with the same devices either for
the automatic changing, or the functions just described for the "cruciform lamp."
LAMP FOR CIRCULAR CIRCUITS.
The lamp I have above described as arranged for a
used with slight modifications for circular circuits.
"
'cross circuit" may also be
The only difference between an ordinary "circular" lamp and an ordinary
<
cross circuit" may also be
"
lamp and an ordinary
The lamp I have above described as arranged for a
used with slight modifications for circular circuits.
The only difference between an ordinary "circular
cruciform
or cross circuit lamp is that in the latter each couple has one of its
clips connected with one clip of the other couples, and with a terminal termed a
central terminal, the other clips being perfectly independent, and in a "circular"
lamp all the clips without exception are perfectly independent of one another, and
have each their corresponding terminal.

page_text: This remark at once indicates the arrangement of my automatic "circular "
lamp, shewn in Figures 9, 10, and 11.
To each inner clip I also add an expanding spring D¹, having the same functions
as that in the "cruciform" lamp.
;
By the side of each couple I place a contact device C¹, having springs and 11
one of these springs is in communication with the next outer clip 2, the other
with the next inner clip p¹, that is to say, that of the same couple as the former
one; the contact piece CT is divided into two parts c¹ and c, electrically insulated
from one another, each in connection with one of the springs. The extinguisher E
is divided into as many insulated parts e¹, e², 3, and c as there are candles, these
parts correspond each with the outer clip p, say, by means of a wire q.
Moreover where contact with the inner clip p is made, one half of the contact
surface is in electrical communication with the outer clip p, for instance, by a
metal band S and insulated from the inner clip p¹ which forms the other half of
the contact.
By referring to the explanation given with reference to the cruciform lamp, the
operation of this lamp will be easily understood. The consumed candle heats the
spring D' which expands and disengages the contact piece C', which operated by
its springs bears against the contact surface, and thus brings the next two clips
and consequently the next candle into the electric current; now either this candle
ignites, the consumed candle is extinguished, and the desired result is at once
attained, or the consumed candle remains ignited; the spring D' then continuing
to expand touches the extinguisher, closes the current upon itself, and causes the
candle to be extinguished.
The spring D¹ being then no longer heated retires or withdraws, and the next
candle is then forced to ignite.
In the circular lamps as well as in the "cruciform" lamps the springs may be
rendered entirely independent, and the current need not be compelled to pass
through the same. For this purpose I may provide two tongues, each connected
with one of the two next following clips of the same couple, which tongues at
the moment of disengagement would be pushed against two surfaces electrically
connected each with one of the two clips of the candle which had just finished.
Here I can likewise obviate the large number of contacts established by the
disengagement, and through which the current has to pass, by adopting an arrange-
ment analogous to that above described with reference to the cruciforin lamp; it
would suffice to connect each of the two springs (or each of the two tongues of
each couple for the other arrangement) with one of the two clips of a candle which
has always to be the first to burn, each spring or cach tongue being at the moment
of disengagement placed in communication with a surface connected with one of
the two clips of the next couple.
In Figure 12 I have indicated in dot and dash lines the elementary circuit sufficient
for my Invention; in this instance, as well as in that of the cruciform lamp, the
lamp has only two terminals, one for the ingoing the other for the outgoing
current.
But to provide against certain accidents the ordinary "circular" arrangement
may be retained, and this is indicated in dotted lines in Figure 12. In this case
the contact pieces of the commutator are made to correspond with the terminals
of the lamp, in order following the direction of the automatic change which must
be the same for all the lamps. In case of accident the change would be effected
by hand.
For the single commutator of this circuit the arrangement shewn in Figure 6
and already described may also be adopted.
In a manner analogous to that described with reference to the cruciform lamp
I can also arrange a resistance device R, Figure 13, equivalent to a candle in
operation for each lamp, into which resistance the current passes after combustion
of the last candle, a contact piece being reserved on the commutator in com-
munication with the resistance device of each lamp.

page_text: It will be seen that my automatic, "cruciform," and circular lamps, &c., all operate
on the same principles. The application of these principles may be extended as
already stated to all electrical systems, not only to those with candles, in which the
current passes from one to the other, but also to electric regulators in which the
current passes from one carbon to the other, to incandescent lamps and the like,
and in general to all electric apparatus wherein it is necessary to change the path
of the current.
I would also remark that in my apparatus disengagement is not necessarily tied
to extinction, the disengagement may take place by an expanding spring acting
either directly or by means of small levers, and the extinguisher may also consist
of a second expanding spring, as shown, or in a small reservoir l, as shewn in
Fig. 14, containing mercury or water, for instance, or any liquid, or of a solid
body of greater or less resistance, communicating with a pole p¹, which when
expanding, as in the thermometer, would touch a small appendage E connected
with the other pole p, and thus closes the circuit upon itself. The springs
themselves of the contact pieces may in their movement when disengaged cause a
sufficiently momentary extinction of the consumed candle by causing them to
touch for a moment any two pieces which are in electrical connection, the one with
the outer clip and the other with the inner clip of the consumed candle.
The extinction or closing of the current upon itself may take place either before,
during, or after the disengagement without materially affecting the automatic
action of the whole, and this whether the same spring serves for the disengagement
and the extinguishing arrangement, or whether the expanding spring serves for
disengagement only and altogether independent devices are adopted for the
extinction.
The engagement of the contact apparatus under the expanding spring which
holds it may be effected either by hand or by the substitution of new candles for
the consumed ones after the periods of lighting; for this purpose it is sufficient
to attach to the spring of the outer clip (in my arrangement) or upon the movable
clip itself, a suitably arranged stop, which when the candle is taken out pushes
against the springs of the contact device or the apparatus itself and engages the
same. This small stop T is shewn on one of the clips in Figure 1.
For effecting the engagement I may also employ the movement of the candle
when it is removed after use or when a fresh one is inserted, by means of a system
of small levers suitably arranged, or by means of small star wheels, &c.
The contact surfaces may be covered with small metallic brushes, which after
the disengagement would take into one another and would thus cause more close
contact.
Lastly. I would observe that my apparatus is entirely independent of the
direction of the current, and that it can be applied to continuous or alternating
currents; I may moreover either embody all the devices above described in one
apparatus, or I may use one or more of them in connection with other forms of
apparatus or devices to which they are applicable.
Having now described the nature of the said Invention, and in what manner
the same may be performed, I declare that I claim,-
1. The application in electric lamps of a device for effecting disengagement by
means of an expanding spring acting either directly or with small levers, or any
other connections in conjunction with contact pieces, springs, tongues, or the like
for placing in the current the candle, carbon, or other device through which the
current is to pass, substantially as specified.
2. The application of an extinguisher or current closer, consisting of a spring or
of a solid or liquid body (mercury or water for instance) in communication with
one of the poles, which body in expanding (under the influence of the heat
produced by the voltaic arc by incandescence or other effect of the current) touches
another solid or liquid body in communication with the other pole (this latter
body being in some cases likewise affected by the current, thereby expanding and
contributing to produce the desired effect), for the purpose of closing the current

page_text: and causing it momentarily to pass (in its entirety or part) through the path thus
established as above stated, the resistance of said bodies being increased or
diminished as desired according to the nature, form, aud section of the bodies
employed, substantially as specified.
3. The application of the parts and arrangements mentioned in the preceding
claims, whether the whole of them be applied simultaneously or only a part
thereof, substantially as set forth.
4. The application of my extinguisher or circuit closer to lamps of any con-
struction wherein the current is passed to all the candles of the lamp at the same
time, but selects one of the same which it consumes, such application of my.
extinguisher rendering the lamp automatic, substantially as specified.
In witness whereof, I, the said Paul Louis Marie Gadot, have hereunto set my
hand and seal, this Thirteenth day of November, in the year 1881.
PAUL LOUIS MARIE GADOT. (L.S.)
15 Witness,
ALBERT CAHEN,
Civil Engineer,
Of Boulevard Saint Denis, 1,
At Paris.