IMPROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT AND IN THE APPARATUS EMPLOYED THEREIN, PARTS OF WHICH APPARATUS ARE APPLICABLE TO OTHER ELECTRICAL PURPOSES
Year: 1874

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
ALSO
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT AND IN THE
APPARATUS EMPLOYED THEREIN, PARTS OF
WHICH APPARATUS ARE
APPLICABLE TO OTHER ELECTRICAL PURPOSES."-A communication from
abroad by François Ernest de Mersanne, of Paris, in the Republic
of France.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 25th April 1874.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
5 of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT AND IN
THE APPARATUS EMPLOYED THEREIN, PARTS OF WHICH APPARATUS ARE ALSO
APPLICABLE TO OTHER ELECTRICAL PURPOSES," a communication to me from
A

page_text: abroad by François Ernest de Mersanne, of Paris, in the Republic of
France, to be as follows:-
This Invention relates to an improved mode of producing electric
light, and is based upon the emission. of a succession of sparks by the
alternate passage and interruption of a current between the rheophores
or electrodes of a regulator, the arrangement admitting of the electric.
currents or light being distributed as desired whatever may be the power
of the source of electricity from which those currents are derived.
Either a constant or an intermittent light may be obtained according as
the sparks succeed each other more or less rapidly than the duration of
the impression upon the retina, and the light is prevented from being
extinguished, the effect being reproduced at each vibration.
The Invention also embraces the employment of circular or cylindrical
electrodes composed of carbon or other suitable material, to which a
constant rotatory motion is imparted which renders the wear more
uniform, whilst at the same time they are more durable than the
ordinary crayons. These improved electrodes are also applicable to
apparatus of different construction from those herein-after described.
In carrying out this Invention the apparatus is varied according to
the purpose to which the electro light is to be applied.
When the light is to be employed as a coast light or in lighthouses, or
other similar situations, the apparatus is constructed in the following
manner-Four rotating discs composed of carbon or other suitable
material are employed, arranged two by two opposite each other, and
actuated by cams or eccentrics, which impart to the discs an alternate
rising and falling motion, so as to cause the sparks to be produced
alternately between cach pair of discs. By taking the precaution to
determine the maximum distances apart due to the impact of the discs
so as to prevent any liability of the sparks breaking from their excessive
length the circuit will be always closed by the voltaic arcs.
The light
can only be extinguished in one pair of discs by the contact of the
adjacent pair of discs, and a succession of sparks as rapid as desired and
of equal length and intensity may be obtained.
In the case of a single light if it is necessary that the spark should

page_text: apart due to the impact. A frame is provided formed of three columns.
or pedestals, which are supported on a floor or base plate, and carry the
whole of the working parts.
Rotatory motion is imparted to the discs by means of pullies, which
are connected together by india-rubber cords, and derive their motion
from a friction roller, which is arranged on a sleeve or socket pieco
surrounding one of the pulley shafts, and is actuated by a rotatory plate
put in motion by the driving mechanism. The sleeve or socket piece
carrying the friction pulley is capable of being moved longitudinally
along the shaft, in order to accelerate the motion of the discs in pro-
portion to their wear, the speed of the pulley increasing in proportion to
its distance from the centre of the rotatory plate. This longitudinal
adjustment of the friction roller is effected by means of a balanced
guide, which is moved by a nut working on a stationary horizontal
screw. The exterior of this nut is provided with teeth, and forms a
pinion which is actuated by a train of gearing set in motion by a rack,
which rack is caused to descend by means of a cam arranged at the
upper part of the apparatus, and oscillating under the action of a screw
to which motion is imparted by the driving mechanism. This cam also
accelerates the descending speed of the discs in proportion to their wear.
The nut through which its actuating screw works slides in open guides,
so that it is free, as is also the nut of the horizontal screw when it
arrives at the end of its traverse, and all liability to a fracture of the
parts is prevented. Cams or eccentrics are provided for the purpose of
imparting to the upper discs through the intervention of their rods and of
a roller the rising and falling motions necessary to produce the successive
acts of contact of the two pairs of discs. These cams or eccentrics may
be varied in form, according to the effect and the duration of tho
contact which it is required to produce. By making them of a multiple
action the speed of rotation may be reduced, whilst at the same time.
retaining an ample number of contacts per second. They are provided
with a groove or recess in which their guide roller works, which facilitates
lubrication, and are suspended from the cam herein-before referred to,
and actuated by means of an india-rubber cord and pullies from the
driving mechanism. The whole of the front part of the apparatus is
attached to the frame by a series of small connecting rods, which con-
stantly maintain the working parts parallel in any position. The points
of rotation of the shafts in their bearings near the discs are protected or
°
2.

page_text: In order to bring the lower discs always into contact with the upper
discs and regulate the distance apart due to the impact so as to contribute
to the uniformity in the length of the sparks the lower discs are sup-
ported by forked rods attached to the upper end of helical springs, the
tension of which may be regulated by a knob and rack connected to the
lower portion of the springs.
In lieu of the helical springs other arrangements of apparatus
admitting of a uniform degree of tension being obtained may be
adopted.
According to one modification a chamber immersed in a liquid is
employed, the weight of such chamber being susceptible of variation
to suit the required spring power, and the dimensions of the rod being
so calculated that the displacement will compensate for the loss of
weight caused by the wear of the discs. Thus, for example, the chamber
may be filled with water and air, and the cylinder or receptacle in which
it dips may contain mercury, an air pump being employed for the
purpose of forcing air into an elastic ball or vessel enclosed within the
floating chamber, and thus varying the quantity of water or other
liquid contained in such chamber so as to regulate the pressure of the
lower upon the upper discs. The surplus water or other liquid displaced
by the air forced into the floating chamber is conducted into a receptacle
provided for this purpose.
By increasing the size of the apparatus water may be substituted for
mercury in the water cylinder or receptacle. This system of spring is
particularly advantageous when ordinary crayons are employed. In
order to correct any variations in the intensity of the light resulting
from a want of homogeneity of the carbons and an inconstancy of the
current, there is placed on the lower extension of the rod which supports
each of the lower discs a cylinder of soft iron which moves in the axis
of a bobbin, through which the current passes and forms an electro-
magnet, the attraction of which will adjust or correct the strength of
the spring proportionately to the intensity of the current, and thus
automatically regulate the force of the impact and consequently the
length of the sparks.

page_text: The lower discs are electrically insulated from the rest of the
apparatus by means of pieces of vulcanized india-rubber arranged on
the shafts and the bearings of such discs. The positive pole is placed in
communication with the lower discs (which are in electric communi-
cation the one with the other) by a binding screw applied to the support
of the springs, and the negative pole with the upper discs by another
binding screw placed at any suitable part of the apparatus.
In applying this Invention to the production of the regulation lights
of ships or vessels the apparatus generally may be greatly simplified,
and as the stability and uniform intensity of the luminous point are not
absolutely necessary the working parts employed, in order to obtain
these results, may be dispensed with. When required for night
signalling at sea or on land the apparatus may be constructed in a
similar manner, but ordinary crayons may if desired be substituted for
the discs, and consequently the mechanism employed for the purpose of
effecting their rotation dispensed with, or one dise and one crayon may
be used in combination.
In order to impart motion to the regulating apparatus various means
may be employed. In the case of coast lights and lighthouses the
system of descending weights adopted in lighthouses is preferred, but
for ships' lights a reaction apparatus worked by compressed air from a
pump driven by the prime mover of the electro-magnetic machine may
be used for the purpose, the air being conducted through india-rubber
tubes in the interior of the masts. This latter arrangement is also
adapted for use on board ship for night signalling, but for military
purposes a fan would answer the purpose.
I shall now proceed to describe the apparatus which it is proposed to
employ for distributing the electric currents or dividing a main current
into a number of independent currents of the required intensity. In
these apparatus the whole of the current which is required to be divided
passes in succession into the various conductors which are to be
supplied, and it never leaves one direction before it commences to pass
in another direction. The apparatus is composed of a rotatory shaft
provided at each end with a double metallic brush. The right hand
brush carrier is insulated from that of the left hand by a sleeve or
socket piece, or the shaft itself may be divided into two parts united by
an insulating block, which will also serve as the driving pulley of the

page_text: apparatus. In front of each of these brushes there is placed a wooden
board provided with two series of projecting plates or strips of copper
which are arranged concentrically and correspond to the two portions of
the double brush. These form a number of arcs with spaces between
them, the spaces between one series of arcs being greater than the arcs
placed concentrically thereto, so that the brush does not leave a plate or
strip of one series before being in communication with a plate or strip
of the other series.
In the case of reversed currents the current may be conveniently
divided into four by means of an apparatus consisting of two boards,
each having two series of sixteen plates or strips, the current arriving
at the two double metallic brushes herein-before described. Four
binding screws are provided, each of which communicates with four
plates or strips of each series, the corresponding binding screws of cach
of the plates or strips communicating with two carbon points of a
regulator. The current will pass in one direction or the other, according
to the direction in which it is emitted at that instant, and for a complete
turn of the apparatus cach of the carbon regulators will have received
four series of currents. By regulating the speed therefore so that the
succession of sparks shall be more rapid than the duration of the
impression of the light upon the retina the light will appear continuous,
and will be augmented within certain limits with the speed of the
metallic brushes. In lieu of the plates or strips two series of studs may
be arranged on the boards sufficiently close together, or one series of
studs and a concentric annular ring within same may be employed, such
ring communicating with the binding screws through the intervention
of a more resisting circuit, which necessitates the current passing in a
larger quantity through the upper brush, and the conducting wires
terminate in a carbon regulator, or at any other apparatus in which the
electricity is required to be utilized.
When motion is communicated to the brushes by the shaft of the
magneto-electric machine which produces the electricity, the two boards
may be arranged either both on one side or one on each side of such
machine. When the main current has to be divided into, say, only five
or six secondary currents, it will be sufficient to employ a single brush
carrier provided with four series of studs or of plates or strips, and two
double brushes insulated from each other, and each communicating by

page_text: a special conducting wire with one of the poles of the circuit which it
is desired to close.
When the source of the electricity is a magneto-electric machine with
the currents passing in one direction only, the apparatus simply consists
of one brush and one board having two series of studs or of plates or
strips.
In order to prevent the heating of the parts which might result from
the friction of the brushes on the studs it is proposed to employ a
peculiar description of rotatory rubber consisting of a circulur metallic
brush which is loose on its axis, but which under the action of a flexible
spring, the pressure of which may be varied, is prevented from turning
too freely, whilst at the same time its periphery is maintained in contact
with the stud or with the plate or strip. The stud or the plate
or strip is also provided with a projection having sharp edges and
slightly inclined in the direction of the motion of the brushes, so that
a slow rotatory motion is imparted to the brushes which ensures the
change of the surfaces in contact and prevents the heating of the
parts.
Another modification of distributing apparatus has for its object to
prevent in the case of an accidental rupture of the circuit the sparks
produced deteriorating the parts. The machine is composed of a
rotatory square horizontal shaft, carrying any suitable number of
eccentrics, which aro keyed at equal distances around the shaft and are
provided with metal pendent rods pointed at their lower extremities
and dipping at cach oscillation in a cup or vessel containing mercury,
or a less liquid amalgam, so that should an accidental rupture occur the
spark would enter the liquid.
The shaft is also provided with a series of graduated plates arranged
alternately with the eccentrics, above each of which plates there is placed
a hand or pointer secured to the frame, which arrangement admits of the
discs (which are also graduated) being properly and uniformly keyed on
to the shaft. Each eccentric is cast with a circular moulding or rim
capable of turning on a socket piece, and the latter has a central square
opening and is mounted on the shaft; a worn or endless screw and
worm wheel are provided to facilitate the adjustment of the eccentric
in accordance with the indications of the hand or pointer, and the
graduated plate during the operation of keying.

page_text: The transmitting apparatus to be employed with the distributing
apparatus herein-before described may be arranged in various ways.
For the service of lighthouses a board provided with studs may be
provided in front of the distributing apparatus, such studs being in
electric communication with the various conducting wires leading to
the studs or binding screws of the distributing apparatus. In order
to effect all the combinations possible it is simply necessary to bring
down upon the studs an insulating plate perforated with holes, tho
application of which plate regulates through which wires the current
is to pass. A succession of such plates disposed in the form of an
endless chain admits of determining the periodicity of the effects to be
obtained.
For signals a similar apparatus may be used, but it is preferred to
adopt a transmitting apparatus analogous in principle to that employed
in electric telegraphs.
The improved system of distributing currents may also be applied
with advantage to other purposes, such for example as clectro-metallurgy,
telegraphy, chemical decomposition, blasting operations, the production of
heat, and for obtaining power. In applying it to the deposition of metals
the use of the peculiar transmitting apparatus admits of divided currents
being directed to a number of baths simultaneously, each current having
the intensity necessary for the operation to be performed.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Scal Patent
Office on the 23rd October 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JoпN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
2
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of April, in the year 3
of our Lord One thousand eight hundred and seventy-four, in the
37th year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Henry Johnson, Her special

page_text: license that I, the said John Henry Johnson, my executors, admini-
strators, and assigns, or such others as I, the said John Henry
Johnson, my executors, administrators, or assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "Im-
PROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT AND IN THE APPARATUS
EMPLOYED THEREIN, PARTS OF WHICH APPARATUS ARE ALSO APPLICABLE TO OTHER
ELECTRICAL PURPOSES," a communication to me from abroad by François
Ernest de Mersanne, of Paris, in the Republic of France, upon the con-
dition (amongst others) that I, the said John Henry Johnson, my exe-
cutors or administrators, by an instrument in writing under my hand and
scal, should particularly describe and ascertain the nature of the said
3 Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings and to the letters and figures marked thereon, that is to
say:―
The said Invention relates to a novel method of producing electric
light, and is based upon a succession of rupture sparks (obtained by
alternately establishing and breaking contacts) between the rheophores or
electrodes of a regulator, the arrangement admitting of the light being
divided or distributed as desired, whatever may be the power or the
nature of the source of electricity from which the currents are derived.
In carrying out the said Invention various peculiar apparatus aro
employed, both for the production of the light, and for the preliminary
division or distribution of the currents.
The light derived from a succession of electric sparks appears either
3 intermittent or constant, according to the rapidity with which the
sparks succeed each other, and is not liable to be extinguished by wind
or rain, as it is constantly relighted at each vibration. The light may

page_text: Figure 1 (Sheet 1) represents a side elevation of an apparatus intended
to be applied to the production of coast lights, the illuminating of light-
houses, and other similar purposes; Figure 2 (Sheet 1) is a front clevation
of same.
Figures 3, 4, and 5 (Sheet 2) are horizontal sections taken respectively
along the lines A, B, C, D, and E, F, (Figure 1).
This apparatus is composed of four discs A, A₁, of charcoal or other
suitable material, disposed two by two opposite each other and revolving
on their own axes, whilst the upper discs have in addition a vertical
reciprocating motion imparted to them, which is so arranged as to cause
the sparks to be produced alternately between each pair of discs. By
limiting by suitable means the maximum extent of the separation of the
discs the circuit always remains closed by the voltaic arcs themselves,
and in the case of two pairs of discs operating alternately the light can
only be extinguished between the two discs of one pair by the contact of
the two discs of the neighbouring pair, and a succession of sparks as
rapid as desired and of equal length and intensity may be obtained.
The apparatus is carried on a frame B formed of three columns or
pedestals supported on a foundation or base, and comprises three sets or
groups of distinct and independent working parts, which are herein-after
described in succession.
The first set or group is common to both the upper and the lower discs,
and is arranged in the following manner:-Rotatory motion is imparted to
the discs by means of pulleys a connected together by india-rubber cords,
and which derive their motion from a friction roller actuated by the
rotatory plate c, which is set in motion by the driving mechanism.
In order to accelerate the motion of the discs in proportion to their
wear, and cause the upper discs to descend relatively thereto, the roller b
is mounted on a sleeve or socket piece, which is capable of moving longi-
tudinally along the shaft a¹, so as to increase the speed in proportion to
its distance from the centre of the plate c. The motion of the roller b
along the shaft a¹ is effected by means of a counterbalanced guide d,
which is moved by a nut e¹ working on a horizontal non-rotating screw c.
The exterior of this nut is provided with teeth and forms a pinion
which is actuated by a train of gearing e² set in motion by a rack f, which
rack is caused to descend by means of a cam 9 disposed at the upper

page_text: part of the apparatus, and moved to and fro under the action of a
screw h, to which motion is imparted by the driving mechanism.
The second set or group of working parts is peculiar to the upper
discs A, A, and is intended to impart to the same the reciprocating
rectilinear motion which is requisite in order to produce the successivo
acts of contact. For this purpose a reciprocating rising and falling
motion is imparted from the cams or eccentrics I through the inter-
vention of rollers 1 to the rods C which carry the upper discs A, A, such
cams or eccentrics I being suspended from the cam g and actuated by
means of an india-rubber cord from the driving mechanism. In order
to admit of this up-and-down motion of the discs and of the parts which
actuate them the whole of the front portion of the apparatus is attached
to the frame B by a series of small connecting rods j, by which means
the parallelism of the combined moving parts is constantly ensured in
all positions. The points of rotation of the shafts in their bearings near
the discs are protected from the heat by small curved pieces or shields
suitably disposed for that purpose.
The third set or group of working parts is peculiar to the lower discs
A₁, A₁, and has for its object to constantly bring back such discs into
contact with the upper discs A, A, and to regulate the extent of separa-
tion due to the shock or impact so as to contribute to a uniformity in the
length of the sparks. The lower discs A₁, A₁, are supported by forked
rods D, D, attached to the upper part of helical springs k, the tension
of which may be regulated by the aid of racks D' connected to the lower
end of the springs and operated by means of knobs or handles E.
The electric current is transmitted in the following manner, videlicet:
-The lower discs are electrically insulated from the rest of the apparatus
by pieces 2 of vulcanite disposed on the shafts and supports of the discs,
as shewn by the thick lines. The positive pole is placed in communi-
cation with the lower discs A₁, A₁, (which are in electrical communication
with each other) by means of a binding screw F attached to the support
G of the springs k, and the negative pole is placed in communication
with the upper discs A, A, by means of another binding screw placed at
any suitable part of the apparatus.
Assuming now two pairs of discs placed in juxtaposition, as shewn in
the Drawing, so as to operate alternately, and each giving fifteen sparks
per second, thirty successive emissions of light will in reality be obtained

page_text: in one second, and the sensation produced will be nearly constant.
Moreover it will be seen from the form of the cam or eccentric, repre-
sented in Figure 12 (Sheet 3), that the spark remains constant at its
maximum of intensity for about three-quarters of the revolution of the
discs, and that the duration of the contact is instantaneous. By em-
ploying cams or eccentrics of a multiple action of the description shewn
in Figures 13, 14, 15, and 16 (Sheet 3), the speed of rotation may be
considerably diminished, whilst still obtaining an ample number of
contacts per second. In all cases the arrangement of the cam groove,.
which is shewn in Figure 17 (Sheet 3), ensures the perfect lubrication of
the conducting roller which is constantly working therein.
in.
Assuming that as a condition favorable to the production of the light
and the uniformity in the wear of the discs it is desirable to impart to
them a constant tangential speed of 04. per second it is obvious that
with discs of a radius of 16 the initial speed of rotation would be say
one revolution in about 240 seconds. Taking now the wear of the
existing crayons of 01 of a square inch at say two inches per hour, which
figure is generally adopted by experience (with crayons composed of
retort charcoal), it may be estimated that a disc of a radius of 16. and
32. in thickness by constantly rotating for fifteen hours will be reduced
to a diameter of 5, which will be the waste of the disc, the useful
periphery having a thickness of 1., and it will be completely worn out
after three hundred and six revolutions.
in.
Having established these points the increase in the angular speed
which it is requisite to impart to the discs in order to maintain their
tangential speed constant may be readily determined, as also the accele-
ration of their downward motion in order to constantly maintain the
position of the luminous point invariable, which conditions are absolutely
essential to the fixedness and constancy of the light. In order to obtain
this result the cam g is made of such a form as to effect the increase in
the descending speed of the upper disc, whilst at the same time it
actuates the rack f, which causes the pinion nut e¹ to rotate and traverse
the screw e along guides, and with it the friction roller b along the
plate c, whereby the speed of rotation of the roller is accelerated in
proportion to its distance from the centre of the plate.
In order to prevent any liability of a fracture of the mechanism the
nut 3 which actuates the cam g is simply maintained by projections 4

page_text: sliding in guides 5, which are open at their lower end, and from which
the nut 3 is free when it arrives at the bottom of its stroke, when its
action upon the mechanism ceases. The horizontal screw e is also so
arranged that when it arrives at the extremity of its traverse the pinion
nut e¹ ceases to act thereon. It may be observed that if by reason of
the varied qualities of the carbons it should be found necessary to vary
their speed this may be effected by substituting variable cone pulleys for
a portion of the gearing employed for transmitting the motion.
The loss of weight of the lower discs by reason of their wear nearly
counteracts the effect of the diminution in the tension of the springs,
resulting from their elongation. Other arrangements of apparatus may
however be employed, admitting of a tension as constant as possible,
being obtained as herein-after described. These apparatus are composed
of a vessel immersed in a liquid, and the weight of which may be varied
according to the force of spring which it is desired to obtain, the parts
being so arranged that the effect of the wear of the discs will be com-
pensated for by the rising of the vessel in consequence of the reduction
in their weight.
l
In the arrangement, Figure 7 (Sheet 2), the lower disc A 1 is carried
by a rod D attached to the upper end of the receptacle 7, filled partly
with water and air, and dipping into a cylinder l' containing mercury.
The quantity of water or other liquid contained in the floating
receptacle may be varied by means of an air pump and india-rubber
tubing, and the pressure of the lower discs upon the upper discs in this
manner regulated. These arrangements are represented more in detail
in Figure 6, which Figure shews the air pump m and the receptacle 6,
into which the excess of water displaced by the air which is forced into
the receptacle is conducted.
By increasing the dimensions of this apparatus in the required pro-
portion water may be substituted for mercury, as shown on one-half the
scale in Figure 9. In this case, as also in the arrangement Figure 8,
the receptacle is provided at its upper end with an elastic or expanding
ball or vessel 7, the volume of which may be varied at pleasure by
forcing air therein by means of a pump. This system of spring, the
perfect regularity in the action of which is independent of its stroke, is
particularly advantageous when crayons are employed, as the rheophores
or electrodes, as shewn at A₁, A₁, in the mercurial apparatus, Figure 6,
and in the apparatus in which water is employed (Figure 8).

page_text: The alternate motion of the discs prevents the formation of any head
at the negative pole, and as moreover the greatest wear always takes
place at the positive pole, which corresponds to the lower discs, it will
be simply necessary to increase the diameter in proportion, the operation
of the regulator (which is based upon the wear of the upper negative
carbon) not being in anywise affected thereby.
In order to correct the variations in the intensity of the light, which
may result from the want of homogencity in the carbons and the
inconstancy of the current, the following arrangement (not shewn in the
Drawings) may be employed:-On the lower prolonged portion of the
rod which supports each lower disc there is disposed a cylinder of soft
iron which moves in the axis of a bobbin traversed by the current, so
that the attraction of the electro-magnet thus produced will adjust the-
force of the spring proportionately to the intensity of the current, and
thus regulate automatically the force of the shock or impact, and con-
sequently the length of the sparks.
Figure 10 (Sheet 3) is a side clevation, and Figure 10 a front elevation
of one example of an apparatus designed for producing the regulation
lights of ships. In applying the Invention to this purpose it is not.
essential that the position of the luminous point should be absolutely,
invariable, nor that its intensity should be perfectly constant, the parts
employed in the arrangement herein-before described for effecting these
objects are therefore in this case dispensed with. It will be scen on
reference to Figures 10 and 11 that the apparatus for effecting the rising
and falling motion of the upper discs A, A, by means of the cams or
eccentrics I is similar to that of the preceding arrangement, but greatly
simplified. In reference to the parts which are peculiar to the lower
discs A₁, A₁, only a certain increase in the length of the springs k is
required, since as the position of the luminous point is no longer
invariable the lower discs A₁, A₁, and their attachments are required to
rise a distance equal to the sum of the wear of the two discs in contact.
This apparatus is therefore extremely simple and cheap, and it is not
essential that it should be protected from rain and wind.
When the Invention is applied to the purposes of night signalling on
land or at sea, the apparatus are similar to those lastly herein-before
described, but as they are not required to operate for so long a period
ordinary crayons may be substituted for the discs, the mechanism

page_text: employed for imparting motion to the latter being in that case dispensed
with, or only a single disc or a single crayon may be applied thereto.
The apparatus is thus greatly simplified, and is also exceedingly cheap.
By increasing the number of these apparatus and varying the position.
of their luminous points by the aid of a special manipulator, the whole
of the combinations of signals obtained during the daytime on land or
at sea may be instantaneously produced either directly or in relation to
fixed colored lights serving as datum points, and the requirements of tho
international maritime code or any other system adopted may be com-
plied with.
The following means may be adopted for imparting motion to the
improved regulators, viz. :-In the case of lighthouses, coast lights, and
the like the system of descending weights employed in lighthouses is
preferred. For the regulation lights of ships a reacting apparatus
operating by compressed air from a pump driven by the prime mover of
the electro-magnetic machine may be used, the air being conducted
through india-rubber tubes in the interior of the masts. For night
signalling apparatus a similar arrangement to that lastly herein-before
described may be used on board ship, and in the case of armics in
campaign a fan or blower moved by hand would provide sufficient motive
power.
In the apparatus for dividing or distributing electric currents con-
structed according to this Invention the whole of the current which is
required to be divided passes successively into the various conductors
which arc to be supplied, and it never leaves one direction before having
already commenced to pass in another direction.
The improved regulators hercin-before described are particularly
adapted for the utilization of these currents in the production of the
electric light. This mode of distributing in the desired direction a
current derived from powerful sources of electricity, such for example as
magneto-electric machines, may therefore be applied to such regulators
with facility.
The improved apparatus admit of the distribution of a continuous or
reversed current under the following conditions, viz. :—
First. Division of a main current into a greater or less number of
independent currents of the required intensities, all or any of them
differing from each other in intensity as desired.

page_text: Second. Regularity and constancy as perfect as possible of these
individual currents.
Third. Admission of the main current integrally and without solution
of continuity into the dividing apparatus.
Fourth. Obviating heating in the contacts during the operation of the
apparatus.
Fifth. Application of special manipulators admitting of the mode of
distributing the main current being instantaneously varied.
Sixth. The employment of apparatus, simple, inexpensive, requiring a
small amount of motive power, and capable of being adapted to any
source of electricity, such for example as electro-magnetic machines,
magneto-electric machines or batteries.
This process of dividing or distributing a current in addition to its
application for the simultaneous production of a number of luminous
sources may also be applied to other purposes, such for example as
telegraphy, electro-metallurgy, chemical decomposition, the production
of heat and power, blasting operations, and the like. The same
apparatus may also be employed for again subdividing the secondary
currents resulting from them.
Figure 18 (Sheet 4) represents a side elevation of one modification of
dividing or distributing apparatus; Figure 19 is a corresponding end
view of same; Figures 20 and 21 are details of portions of the apparatus
to be herein-after referred to.
This apparatus is composed of a rotatory shaft o, to each extremity of
which there is attached a double metallic brush p. The right-hand
brush carrier p¹ is insulated from that of the left hand by means of a
sleeve or socket piece q, shewn in section in Figure 20; or the shaft
itself may be divided into two parts united by an insulating block q
capable of serving as the driving pulley of the apparatus, as shewn in
Figure 28. In front of each of these brushes there is placed a board »
provided with two series of copper plates in the form of segments of
rings arranged concentrically, the intervals or spaces between one series
of plates being of less length than the plates of the other series, as
shewn in Figure 21, by which means the circuit is always closed as the
brushes never leave a plate of one series before being in communication
with a plate of the other series.
J

page_text: When motion is imparted to the brushes by the shaft of the magneto-
electric machine which produces the electricity the two boards r, r, may
be arranged both on the same side of the magneto-electric machine t, as
shewn in Figure 24, or they may be placed one on each side, as shewn
in Figure 25.
When the main current has to be simply divided into five or six
secondary currents it would be sufficient to employ a single brush
carrier p¹, as shown in Figure 27, and four series of studs or plates, such
brush carrier being provided with two double brushes p, p, insulated
from cach other, and cach communicating by means of a special con-
ducting wire with one of the poles of the circuit which it is desired to
closc.
When a magneto-electric machine with corrected currents. is the
source of the electricity employed the apparatus becomes reduced to a
single brush p, and a single board r having two circumferences of studs
or plates, as shewn in Figure 26, and may be placed on one side of the
machine. This system of dividing or distributing currents may also be
applied with great advantage to other purposes, such for example as
electro-metallurgy, by the employment of a special manipulator for
directing divided currents to a number of baths simultaneously, each
current having the intensity requisite for the duty to be performed.
In order to prevent the heating which might result from the friction
of the brushes upon the studs or plates, an arrangement of rotating
rubbers is employed, as shewn in Figure 29. These rubbers consist of a
circular metallic brush fitted loosely on an axis but prevented from
turning too freely by means of a highly flexible spring, the pressure of
which is capable of being varied, whilst at the same time ensuring a
perfect electrical communication between the brush and its support.
The stud or plate is also provided with a projection 8 having sharp edges
and slightly inclined to the direction of motion of the brushes u to which
a slow rotatory motion is thus imparted which ensures a change in the
surfaces in contact and prevents the heating of the parts.
Figure 31 (Sheet 5) represents a side elevation of another modification
of dividing or distributing apparatus constructed in accordance with this
Invention; Figure 32 is an end view of same; Figure 34 is a plan of a
portion of the apparatus; and Figures 30, 33, and 35 are diagrams and
details to be herein after referred to. This arrangement not only admits

page_text: of a single current being divided into a number of currents under the
above-mentioned conditions, but it also possesses the advantage that in
the event of sparks occurring from a break in the contacts no deterioration
to the apparatus would result therefrom. This apparatus is composed of
a rotatory shaft carrying cams or eccentrics x, (10 of which are
employed in the example shewn) which are keyed at equal angular
distances around the shaft, as shewn in Figure 30, and actuate metal
rods, the pointed lower extremities z of which are caused to dip at each
oscillation into a cup or vessel w containing mercury or a less liquid
amalgam. It will be simply necessary therefore to suitably arrange the
communications and insulators in order to produce a distributing
apparatus, the operation of which will be readily understood from the
Drawing.
The shaft of the apparatus is square, and has fitted on to it alter-
nately a cam or eccentric x and a graduated disc 9, and above each
dise 9 there is disposed a pointer 10 which is attached to the frame and
facilitates the operation of keying the discs 9 in their proper position on
the shaft v.
Each of the cams or eccentrics is cast with a projecting boss y
capable of turning on a sleeve or socket piece, which latter is made of a
square form on its interior and is mounted upon the shaft v. The boss y
carries an endless screw or worm 11 which engages with teeth 12 formed
on the periphery of the central sleeve or socket piece whereby facility is
afforded for adjusting the position of the cam or cccentric to the requisite
angle which is determined by the position of the pointer on the divisions
of the adjacent graduated disc.
In Figures 31 and 35 the line N represents the level of the mercury
in the cups or vessels w, and the lines n and n¹ the upper and lower
levels of the oscillations of the mercury caused by the motion of the
points, whilst the extreme lines a, b, respectively represent the upper
and lower levels of the stroke of the points z. It will be seen from the
various relative positions of the points shewn in Figure 35, each of which
corresponds to one twentieth of a revolution of the shaft, that between two
successive emissions of currents a moment will always exist in which an
emission will take place simultaneously in these two directions, and
which will ensure the constant closing of the circuit.
Should an accidental rupture of the circuit occur the spark produced
would enter the mercury and no injury to the apparatus could ensue.

page_text: As moreover the mercury is distributed in separate cups or vessels, the
fact of its level not being maintained perfectly horizontal has but little
influence upon the operation of the apparatus.
*In combination with the apparatus for dividing or distributing currents
herein-before described manipulators are employed, having for their
object the facilitating of the use of such apparatus, and they may be
arranged in a variety of ways. For the service of lighthouses a shelf
or table may be placed in front of the dividing or distributing apparatus,
through which shelf or table pass studs which are connected electrically
with the various conductors leading to the studs or binding screws of
the dividing or distributing apparatus. In this case all that is required
to effect every possible combination is to cause an insulating slab per-
forated with holes in a similar manner to that of the cards of a jacquard
loom to descend upon the studs of the shelf or table, the simple act of
applying it to the studs regulating those in which the current is and is
not to pass. By employing a succession of theso slabs disposed in the
[form of an endless chain the periodicity of the results to be obtained
may be effected.
A manipulator of this description may also be used for signals, but it
is preferred to adopt one constructed upon the principle of the dial
manipulator employed in electric telegraphs.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,―
First. The mode of producing electric light by a succession of rupture
sparks between the rheophores or electrodes of a regulator admitting of
the currents or light being divided or distributed at will, as herein-before
described.
Second. The peculiar arrangements and combinations of regulators.
whereby the rheophores or electrodes are alternately brought into contact
and separated for the production of the sparks, according to the special
circumstances under which the light is to be employed, substantially as
herein-before described and illustrated by the accompanying Drawings.
Third. The application and use to and in apparatus for producing
electric light of circular or cylindrical rhéophores or electrodes composed

page_text: of carbon or other suitable material and having a continuous rotatory
motion in substitution for ordinary crayons for the purpose of obviating
the necessity for a frequent renewal of the rheophores or electrodes
employed in the production of the light.
Fourth. The application of springs composed of a vessel immersed in
a liquid to the lower rheophores or electrodes in substitution for spiral
springs for the purpose of ensuring uniformity in the force of the springs,
substantially as herein-before described and illustrated by the accom-
panying Drawings.
Fifth. The peculiar dividing or distributing apparatus having rubbers
and boards provided with studs or plates and so arranged as to effect the
division or distribution of a current into a number of currents of an
intensity equal or proportional to given numbers, substantially as and
for the purposes herein-before described and illustrated by the Drawings
hereunto annexed.
Sixth. The application and use of rotating metallic brushes for pro-
ducing the contacts whilst obviating the liability of heating the parts in
contact, substantially as herein-before described and illustrated by
Figure 29 of the accompanying Drawings.
Seventh. The peculiar dividing or distributing apparatus provided
with cams or eccentrics operating points which are caused to dip in
mercury or other amalgam whereby heating is prevented and all liability
to the deterioration of the apparatus by the accidental emission of sparks
is obviated, substantially as and for the purposes berein-before described
and illustrated by the Drawings hereunto annexed:
Eighth. The application and use to and with the various improved
apparatus of manipulators for the purpose of instantaneously varying the
directions in which a main current is being divided or distributed, as
herein-before described.
In witness whereof, I, the said John Henry Johnson, have to
this my Specification set my hand and seal, the Twenty-third
day of October One thousand eight hundred and seventy-four.
I HENRY JOHNSON (TS)