IMPROVEMENTS IN ELECTRIC LIGHTING AND IN THE APPARATUS TO BE USED THEREFOR
Year: 1882

page_text: LETTERS PATENT to Walter Strickland of Woodford in the County of Essex
"
Gentleman for an Invention of IMPROVEMENTS IN ELECTRIC LIGHTING AND
IN THE APPARATUS TO BE USED THEREFOR
PROVISIONAL SPECIFICATION left by the said Walter Strickland at the
Office of the Commissioners of Patents on the 13th October 1882.
WALTER STRICKLAND of Woodford in the County of Essex Gentleman.
"IMPROVEMENTS IN ELECTRIC LIGHTING AND IN THE APPARATUS TO BE USED
THEREFOR
"
The object of my Invention is to produce a constant and perfectly steady are of light
without the use of any special regulating mechanism as in ordinary arc lamps, also
to increase the time during which an are may continue to run and to form by
division a low resistance to Electric motion within the lamp.
For the purpose of my Invention I use four carbon or conducting pencils to an
arc, which I place in suitable holders and pass between suitable guides to form
two parallel (or nearly so) lines, the poles or points of each pair being in contact
one with another, and maintained so while in action by gravity or other means.
The
The distance apart of the two lines of pencils is regulated according to the
length of arc required, the four points meet at the two poles of the arc.
current which I prefer should be alternating entering preferably by division and
in any suitable proportion at the outer ends of one pair in line and leaving by the
onter ends of the other pair in line-In order to start the Lamp the poles of the
pencils are enlarged so as to bring the two lines into contact when placed in
position.
The Carbon pencils may be used plain, or they may be Electro-plated or coated
with a refractory material, or they may be enclosed in porcelain which is consuined
or vaporised with the Carbon at the arc-generally I use one coppered Carbon and
one refractory encased Carbon in each line, similar pairs being opposite each other
in the two lines. The refractory material thus forms an incandescent keeper or
armature over the light at the two polar points of opposite electrodes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Walter Strickland in the Great Seal Patent Office on the 13th April
1883.
WALTER STRICKLAND of Woodford in the County of Essex Gentleman
"IMPROVEMENTS IN ELECTRIC LIGHTING AND IN THE APPARATUS USED THEREFOR
"
The object of my Invention is to produce a constant and perfectly steady arc of
light without the use of any special regulating mechanism as in ordinary Arc
Lamps, also to increase the length of time during which the same are may continue
to run and to form a low resistance to Electric motion within the Lamp.
For the purpose of my Invention I use four carbon or conducting pencils to
form an arc, which I place in suitable holders and pass between suitable guides
to form two parallel (or nearly so) lines the poles or points of each pair being in
contact one with another and maintained so while in action by gravity or other
suitable means. The distance apart of the two lines of pencils is regulated
according to the length of arc required, the four points forming the two poles of
the are; the same current which I prefer should be alternating, plus and minus,
entering by division at the outer ends of one pair and leaving by the outer ends
of the other pair. In order to start the Lamp the poles of the pencils are enlarged
so as to bring the two lines into contact when placed in position. The carbon
pencils may be used plain, or they may be electro-plated or coated with a refractory
material, or they may be enclosed in porcelain which is consumed or vaporized
with the carbon in the arc, generally I use one coppered carbon and one refractory
encased carbon in each line, similar pairs being opposite each other in the two lines,
the refractory material thus forms an incandescent keeper or armature over the
light at the two polar points of opposite electrodes.
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents in elevation a Lamp constructed to work according to one of
my Improvements as above described. The alternating currents employed enter
and leave by the binding screws a. a. passing by division along the support
rods b. b. to the contact springs or brushes c. c. and sliding arms d. d. which carry
the upper carbon pencils, these rest upon the points of the lower carbon pencils as
shewn in the figure. In order to start the Lamp the pencils are put into communi-
cation at their points by an enlargement or cross piece of carbonaceous material
which being quickly consumed on the passage of the currents acts as a match to
strike the light. During the running of the lamp the upper pencils descend by
gravity as they are consumed and maintain contact with the lower pencils,
whereby a light of great uniformity is obtained entirely free from that fluctuation
which at present takes place.
Figure 2 represents a front and Figure 3 a side elevation (in section at the upper
part) of another form of lamp adapted to work according to my Improvements.
The alternating currents enter and leave by the binding screws a. a. and pass only
through the two lower carbon pencils b. b. The upper carbon c. is coated with a
cement of refractory material or embedded in a slab of the same, or of a car-
bonaceous substance or compound and preferably brought to a form as shown on
cross sections in Figures 2. and 2b. as a refractory material wherewith to make the
slabs, I mostly use lime slaked with a solution of gum, sugar, or other hydro-
carbon. These refractory slabs rest upon the points of the lower pencils, guided
by the tube d, held by the set screw e, to the standard. f. As the slab is
consumed it slides through the tube and thus keeping contact forms an incandescent

page_text: armature to the arc. In order to start the lamp the lower end of the slab is
primed with a carbonaceous cement.
Figures 4 and 5 show a front and side elevation of another lamp in which my
Improvements are brought into operation. Alternating currents enter and leave
by the binding screws shewn at the base a. a. carrying the plus and minus currents
and similarly with b, the back binding screw of b, not being seen in the figure.
Electric currents in any modified form are sent through the upper and lower
carbon pencils the latter of which are encased in porcelain or a refractory substance,
and the former, which may be electro-plated, are held by the arm c attached to the
sliding tube or rod, d, and descends as the feed is required.
Figure 6 represents another form of lamp of the kind called candle Lamps worked
by alternating currents in which I use four carbon pencils arranged two on each side
or face of a slip of refractory material such as lime which I prefer to carbonize or
prepare for carbonization by a solution of hydro-carbon such as gum as herein-
before mentioned and to attach the carbons thereto whilst the material is in a
plastic condition so as to hold them firmly together.
Figure 7 is a cross section by which this arrangement is made clear. a. a are
the holders with their binding screws, and b is the slip of refractory material to
which the carbon pencils c. c. and d. d. are attached. To start the lamp the points
of the pencils are brought into contact by connection on each side of the slip. The
refractory material acts as a reflector at the points by reason of the two arcs
against it and gives out a light like daylight.
I claim as my Invention
First: The mode of producing a perfectly steady are or source of light by means
of a contact keeper or armature at the polar points of the pencils, substantially as
herein described and illustrated in Figures 1 to 5.
Second-The combination of carbon pencils arranged two on each side or face
of a slip of refractory material as herein described and shewn in Figures 6 and 7.
In witness whereof I the said Walter Strickland have hereunto set my hand
and seal this thirteenth day of April in the year of our Lord one thousand
eight hundred and eighty three
WALTER STRICKLAND (LS.)