IMPROVED MEANS AND APPARATUS FOR PRODUCING LIGHT BY ELECTRICITY
Year: 1879

page_text: LETTERS PATENT to Marshall Arthur Wier, of Shepherd's Bush, in the County
of Middlesex, for the Invention of "IMPROVED MEANS AND APPARATUS FOR
PRODUCING LIGHT BY ELECTRICITY."
"
PROVISIONAL SPECIFICATION left by the said Marshall Arthur Wier at the
Office of the Commissioners of Patents on the 20th February 1879.
MARSHALL, ARTHUR WIER, of Shepherd's Bush, in the County of Middlesex.
IMPROVED MEANS AND APPARATUS FOR PRODUCING LIGHT BY ELECTRICITY."
My Invention relates to the production of light by means of powdered sub-
stances caused to pass through or over the field of electric action between two
conductors or electrodes.
Heretofore, so far as I have experimented and am otherwise aware, when powders
have been used for this purpose they have been caused to pass across a compara-
tively wide field of action, that is, through a considerable space from one electrode
to the other, so as to form a stream of particles which in traversing the electric arc
become momentarily incandescent or are burnt up and dissipated, and generally
one pair of electrodes acts only once upon the powder in its passage through the
lamp.
My present Invention consists in arranging the conductors forming the electrodes
of the lamp in such manner that each pair may act upon the same particles of
powder any given number of times during their passage through or across the field
of electric action, whereby the light may be spread over a comparatively large
surface, and its intensity (which in the electric arc is so injurious to the eyes) is
thereby greatly modified. Any number of lights within the power of the generator
inay be placed on one circuit, and the electric force required is much less than where
the electric arc has to be maintained.
In order to effect this I arrange the conductors forming the electrodes in pairs
parallel to but separated from each other by an extremely small distance (preferably
not more than the diameter of the grains of powder, and with or without an insu-
lating substance between them), and then by folding these pairs of conductors upon
each other, or by winding them in pairs upon a mandril or otherwise, I produce an
extended surface forming a kind of grating or ribbed surface of any required shape,
[Price 6d1

page_text: each alternate bar or rib of which is part of one electrode, and the next bar or rib
part of the other electrode. This grating or ribbed surface, horeinafter called the
electrode surface, may be set at a greater or less angle with the horizon, and the
powder allowed to fall down its inclined surface after the manner of a cascade; or
the electrode surface may be placed in other positions, and the powders projected
against it; or the electrode surface may be caused to vibrate to and froin the
powder. Whichever method be employed, the grains of powder as they roll or fall
over, or otherwise come in contact with the alternating conductors forming the
bars or ribs of the cloctrodo surface, mako and break contact therewith several times
before quitting the field of the electric action, thereby causing a large number of
electric sparks to be produced, and the said grains of powder to become white hot
or incandescent, the aggregation or sum total of these sparks and incandescencies
resulting in a brilliant and bright but comparatively soft light. It will be readily
understood that the electrode surface may be made of any desired form and size; it
may be kept in motion or stationary, and may be divided into any number of
separate parts, as each unit of the electrode surface will produce a certain proportion
of light, whether separate from the rest or united thereto. The electric force
required to produce light by the above means and arrangement is simply in propor-
tion to the extent of the electrode surface employed, and is comparatively small,
because the grains of powder act as intermittent conductors, but at the same time
offer sufficient resistance to the passage of the current to cause them to become white
hot while making and breaking contact with the alternating conductors of the
electrodo surface.
The apparatus above described may be employed in vacuo or in an atmosphere
of gas which will not support combustion, such as nitrogen or carbonic acid, and in
these cases the powder may be used over and over again with very little or no loss;
or it may be used in the open atmosphere, but in this case there will be a continuous
consumption of the powdered substance if the latter is at all combustible.
So far as I am at present aware, powdered carbon is best suited to this purpose,
but other powdered or granulated substances which combine sufficient conductevity
and resistance may be employed.
Various mechanical contrivances may be used for raising the powder for re-use
after it has passed over the electrode surface, to project the powder against the said
surface, or to move the said surface to and from the powder; for example, in one
arrangement I receive the powder after it leaves the electrode surface into suitably
shaped receptacles, which at regular intervals of time or on the closing of an electric
circuit determined by the flow of the powder itself are raised from the lower to the
upper part of the lamp by means of clockwork, an electro-magnet motor, by hand,
or otherwise being arranged so as to deliver powder to the electrode surface when
in the uppermost position, and to receive powder from the said surface when in the
lower position. In another arrangement, instead of receptacles raised intermittently,
the powder is received into a receptacle below, and raised by an elevator con-
tinuously; or the glass shade surrounding the lamp may be adapted to rotate by
any suitable mechanical appliance, and to raise the powder by means of ribs or cor-
rugations formed on its internal periphery. In another arrangement the powder is
projected against the electrode surface by means of revolving beaters or otherwise;
and in another arrangement, more especially applicable, for example, to lights
situated in the ceilings of rooms or chainbers, I arrange a horizontal sheet of glass
at the bottom of the lamp, and over it I place an electrode surface, as above
described, a certain quantity of powder being placed between the glass and the
electrode surface, and I cause the said electrode surface to be vibrated up and down
by mechanical or electro-magnetic means, so as to make and break contact very
rapidly with the grains of powder on the glass; this causes the said grains to become
incandescent, and to shew a light downwards.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Marshall Arthur Wier in the Great Seal Patent Office on the 20th
August 1879.
MARSHALL ARTHUR WIER, of Shepherd's Bush, in the County of Middlesex.
"IMPROVED MEANS AND APPARATUS FOR PRODUCING LIGHT BY ELECTRICITY."
My Invention relates to the production of light by means of powdered substances
caused to pass through or over the field of electric action between two conductors or
electrodes.
Heretofore, so far as I have experimented and am otherwise aware, when powders
have been used for this purpose they have been caused to pass across a compara-
tively wide field of action, that is, through a considerable space from one electrode
to the other, so as to form a stream of particles which in traversing the electric arc
become momentarily incandescent or are burnt up and dissipated, and generally
one pair of electrodes acts only once upon the powder in its passage through the
lamp.
My present Invention consists in arranging the conductors forming the electrodes
of the lamp in such manner that each pair may act upon the same particles of
powder any given number of times during their passage through or across the field
of electric action, whereby the light may be spread over a comparatively large
surface, and its intensity (which in the electric arc is so injurious to the eyes) is
thereby greatly modified. Any number of lights within the power of the generator
may be placed on one circuit, and the electric force required is much less than where
the electric arc has to be maintained.
In order to effect this I arrange the conductors forming the electrodes in pairs
parallel to but separated from each other by an extremely small distance (preferably
not more than the diameter of the grains of powder employed), and with or without
an insulating substance between them, and then by folding these pairs of conductors
upon each other, or by winding them in pairs upon a mandril or otherwise, I produce
an extended surface forming a kind of grating or ribbed surface of any required
shape, each alternate bar or rib of which is part of one electrode, and the next bar or
rib part of the other electrode.
In the Drawings Figure 1 illustrates an arrangement in which A and B represent
the two electrodes, connected in the usual way with the generator of electric force.
These electrodes may be of copper or other good conducting substance, and they
may be in the form of wire, but I prefer them to be in the form of strips or ribands,
the breadth of which is so proportioned to their thickness that the cross sections of
the said strips shall be sufficiently large to avoid any serious resistance to the
passage of the current through them. C is a thin layer of insulating material, such
as asbestos paper (which substance I have found well adapted to the purpose),
placed between the two electrodes A and B, but so as to leave the front edges of the
latter a little in advance of the insulating material, as shewn. This pair of elec-
trodes A and B, with the insulating material C between them, is folded backwards
and forwards, as shewn, so as to produce a series of parallel bars or ribs, as before
explained. If preferred, the continuous layer of insulating material C may be dis-
pensed with, and short pieces only of such material used, as shewn at the lower
part of the Figure, for maintaining the proper distance of the electrodes from each
other. Where the same electrode is folded upon itself, as at D, the two parts may
be separated by conducting or non conducting material, or they may touch each
other, or be even soldered together.
Figure 2 illustrates another arrangement, in which A and B are alternate elec-
trodes, as before, but instead of being folded together, as in Figure 1, they are
respectively branches from the main conductors A' and B¹; C, as before, represents
insulating material, or, if preferred, open air spaces between the electrodes A
and B

page_text: Figure 3 illustrates a pair of electrodes A and B wound spirally round a core E
of non conducting material, the electrode A being so placed on the core as not to
touch the electrode B.
Figure 4 illustrates a pair of electrodes A and B with insulating material C
between them, similar to those shewn in Figure 1, but rolled round a mandril or
core E of non-conducting material, such as porcelain or other suitable substance.
Figure 5 illustrates the strip of conductor notched at its edge so as to present a
number of projecting points for the powder to fall in contact with, instead of the
plain edges of the straight strip. The holes in the body of the strip are intended to
permit of the insulating material keying itself into them so as to produce a firm
plate, when the whole is tightly squeezed together, and they are applicable to the
plain strips as well as to the notched ones. Figure 14 illustrates a pair of elec-
trodes A and B, with insulating material C between them, wound round a central
mandril so as to form a disc with a spiral ribbed surface.
The grating, ribbed, or pointed surface, hereinafter called for convenience the 1
electrode surface, when produced as shewn in Figures 1, 2, 5, or 14, may be sot at a
greater or less angle with the horizon, as shewn in Figures 1 and 2ª, and the
conical forms, Figures 3 and 4, may be placed with their axes vertical, inclined, or
horizontal. In any case the powder is allowed to fall down the inclined electrode
surfaces after the manner of a cascade; or the electrode surface may be placed in
any convenient and suitable position, and the powder projected against it; or the
electrode surface may be caused to vibrate to and from the powder, as will be here-
after explained. Whichever method be employed, the grains of powder as they roll
or fall over, or otherwise come in contact with the alternating conductors A and B,
forming the bars or ribs of the electrode surface, make and break contact therewith
several times before quitting the field of the electric action, thereby causing a large
number of electric sparks to be produced, and the said grains of powder to become
white hot or incandescent, the aggregation or sum total of these sparks and incan-
descencies resulting in a brilliant and bright but comparatively soft light. It will
be readily understood that the conductors A and B may be arranged in a variety of
ways so as to forin the electrode surface, which latter may be made of any desired
form and size; it may be kept in motion or stationary, and may be divided
into any number of separate parts, as each unit of the electrode surface will
produce a certain proportion of light, whether separate from the rest, or united
thereto.
The electrode force required to produce light by the above described means and
arrangements is simply in proportion to the extent of the electrode surface employed,
and is comparatively small, because the grains of powder when supplied to the
electrode surface in proper proportion (which is best determined by experiment in
each case) act as intermittent conductors, but at the same time offer sufficient
resistance to the passage of the current to cause them to become white hot while
making and breaking contact with the alternating conductors of the electrode
surface.
It will be understood that in the Figures 1, 14, 2, 24, 3, 4, and 14 the distance
apart of the electrodes A and B and the size of the latter in Figure 4 are exagge-
rated for the sake of clearness. I have found the best results when the strips or
ribands are placed at a distance of about one hundredth to one thirty second of an
inch from each other, and the diameter of the grains of powder about the same
dimensions.
The apparatus above described may be employed in vacuo or in an atmosphere
of gas which will not support combustion or combine chemically with the powder,
whether the latter be cold or heated, such as nitrogen or carbonic acid gas, and
in these cases the powder may be used over and over again with very little or
no loss; or it may be used in the open atmosphere, but in that case there will
be a continuous consumption of the powdered substance if the latter is at all i
combustible:
So far as I am at present aware, powdered carbon is the material best suited to

page_text: the purposes of this Invention, but other powders or granulated substances which
combine sufficient conductivity and resistance may be employed.
Various mechanical contrivances may be used for raising the powder for re-use
after it has passed over the electrode surface, or to project the powder against the
said surface, or to move the said surface to and from the powder; for example, in
one arrangement, illustrated in partial section in Figures 6 and 7, the powder after
it leaves the electrode surface is received into suitably shaped receptacles H, H,
which are alternately turned quickly into the upper and lower positions in the lamp
by means of clock work in the box I, an electro-magnetic motor, by hand, or other-
wise, at regular intervals of time, or on the closing of an electric circuit through an
electro-magnet J by the hinged piece K falling upon the contact piece K¹ in the
upper receptacle when the powder therein has fallen sufficiently low to admit of it.
This current magnetizes the electro-magnet J, and the armature J of the latter
liberates the clockwork in the box I, which causes the axis L to make a half revo-
lution, raising the full receptacle into the higher position and lowering the empty
one into the lower position, the hinged piece K falling away from the contact piece
K when the receptacle H arrives at the lower position. Each of these receptacles
H, H, is arranged so as to deliver the powder to the electrode surface when in the
uppermost position through the aperture M¹ of the funnel shaped part M of the
receptacle, and to receive powder from the said surface through the hopper N and
aperture M' when in the lowermost position. The electric connexions from the
electrode surfaces B may be carried through the axis L to contact springs in a
manner well understood by persons conversant with electric apparatus. The lamp
illustrated in Figures 6 and 7 is adapted to shew a light straight forward. Figure
8 illustrates in partial section a similar arrangement, but with conical electrode
surfaces adapted to shew a light all round. The powder after falling over the
electrode surface passes through the holes P, P, into the lower receptacle. This
apparatus is shewn enclosed in a glass case Q, turning when required on centres
L, L, working in the frame R, supported from above or otherwise. S is the con-
ducting wire to one conductor of the electrode surface, and T the conducting wire
to the other.
Figures 9 and 10 illustrate partly in section an arrangement by which the
powder is raised by the elevators W, W, formed on or attached to the inner peri-
phery of the glass case Q by any convenient and suitable means. The elevators
may be made of glass, so as to obscure the light emanating from the electrode sur-
faces B as little as possible. The lamp shewn in Figures 9 and 10 is adapted to
shew a light both forwards and backwards. The glass case Q is caused to rotate at
a speed sufficient to return all the powder to the hopper M as fast as it is supplied
to the electrode surface B.
Figures 11 and 12 illustrate another arrangement, in which, instead of receptacles
raised intermittently, the powder as it leaves the electrode surface B is received on
the bottom of the glass shade or case Q, and the latter being kept in sufficiently
rapid rotation by means of a driving strap U or otherwise, the powder is carried up
by centrifugal action, and encountering the scraper or brush V as it rises is swept
off thereby into the hopper M, whence it is supplied to the electrode surface ZB
through the aperture M¹, as before; the electrode surface A is in this case suspended
on the centres L, L, so as to remain vertical while the glass shade or case Q revolves.
The lamp, as illustrated in Figures 11 and 12, shews a conical electrode surface
adapted to shew a light all round.
According to other arrangements the powder may be projected against the elec-
trode surface by means of revolving beaters, fan blades, or other inechanical devices,
which being well known I have not thought it necessary to illustrate in the
Drawings.
Figures 13, 14, and 15 illustrate partly in section another arrangement, more
especially applicable, for example, to lights situated in the ceilings of rooms or
chambers. A sheet of glass Q of flat or other suitable shape is placed at the bottom
of a box Q¹, and over it is placed an electrode surface B formed to correspond with

page_text: the shape of the glass Q. Some powder (the quantity to be ascertained by trial)
being placed between the glass and the electrode surface AB, the box Q¹ along with
the electrode surface is caused to vibrate or reciprocate up and down by the action
of an electro-magnet X, X, or by mechanical or other means, so as to shake the
powder up and down alternately against the electrode surface and the glass Q,
thereby making and breaking contact very rapidly between the electrodes by means
of the grains of powder. This causes the said grains to become incandescent in the
same way as when falling over or being projected against the electrode surfaces, and
the light is shewn downwards.
The glass shades or cases Q containing the electrode surfaces in each of the above
cases may be exhausted of air, or made to contain nitrogen, carbonic acid, or other
gas, as herein before explained.
Where similar letters of reference occur in the various Figures of the Drawings
they refer to like parts.
Having now described the nature of my said Invention, and the manner in which
the same is to or may be carried into effect, I would have it understood that I inake
no claim to the production of light by passing powdered substances through or across
the electric arc, as I am aware that such means have before been employed, but
what I claim as my Invention is,-
First. The means of producing light by electricity by dropping powdered or gra-
nulated substances of the kind herein before described over or projecting the
same against electrode surfaces formed by arranging the conductors or electrodes
parallel to but separated from each other by a distance proportioned to the size of
the grains of powdered or granulated substance, or by vibrating or reciprocating the
said electrode surface to and from such powdered or granulated substance, substan-
tially as hereinbefore described.
Second. Arranging the conductors, or electrodes, or branches thereof alternately
and parallel to each other, but separated by a distance proportioned to the size of
the grains of powdered or granulated substance, and with or without insulating
substances between them, so as to form a grated, ribbed, or pointed electrode surface,
the circuit through the alternating conductors of which is made and broken by the
contact with such conductors of powdered or granulated substances, substantially
as herein before described, and illustrated in the Drawings, and for the purpose set
forth.
6
Third. In lamps for the production of light by electricity by the means and arrange-
ments set forth in the above first and second claims, the various arrangements or their
equivalents for collecting the powdered or granulated substances after they have
passed over the said electrode surface, and of returning the same thereto for re-use,
substantially as hereinbefore described, and illustrated in Figures 6, 7, 8, 9, 10, 11,
and 12 of the Drawings.
Fourth. The arrangement and adaptation of lamp wherein the light is produced
by causing the electrode surface to vibrate or reciprocate to and from the powdered
or granulated substance, substantially as bereinbefore described, and illustrated in
Figures 13, 14, and 15 of the Drawings.
In witness whereof, I, the said Marshall Arthur Wier, have hereunto set my
hand and seal, this Eighteenth day of August, in the year of our Lord One
thousand eight hundred and seventy nine.
MARSHALL ARTHUR WIER, (L.S.)