IMPROVEMENTS IN ELECTRIC LAMPS
Year: 1882

page_text: LETTERS PATENT to Andrew Smith Church, of San Francisco, California
United States of America, now of Wellington Road, St. John's Wood, in the
County of Middlesex, for an invention of "IMPROVEMENTS IN ELECTRIC
LAMPS A communication from abroad by John B. King, of Brooklyn, New
York, United States of America.
"
PROVISIONAL SPECIFICATION left by the said Andrew Smith Church at
the Office of the Commissioners of Patents on the 17th April 1882.
ANDREW SMITH CHURCH, of San Francisco, California, United States of
America, now of Wellington Road, St. Johns Wood, in the County of Middlesex
IMPROVEMENTS IN ELECTRIC LAMPS [A communication from abroad by John
B. King, of Brooklyn, New York, United States of America.]
"
Heretofore the carbons for use in electric arc lamps have been made solid and
when the electric current traverses the same the ashes or unburned hydro-carbon
falling from the positive onto the negative pole causes a flickering and unsteady
light. The ashes continually falling upon the negative pole prevent an equal
combustion of the carbons.
The object of this invention is to keep the carbons clean; to ensure a steady
light; to equalize combustion; and to cause the carbons to last longer than
heretofore.
In carrying the said invention into practice I provide for the introduction of
moist atmospheric air through the centre of the carbons, at the same time as an
electric current is passed through the centre of the carbons by means of a spiral
conductor, that is to say; I make an aperture or channel running directly through
the centre of the carbons from apax to base, and a current of oxygen of the air is
admitted through the channel or aperture. At the base of the carbons I attach a
cup or metal tube in which I place a wet sponge. On the inner side of the said
sponge is secured a piece of wire ganze and through these parts the air passes.
Price B1
In

page_text: the aperture through which the air passes, a fine spiral wire runs from base to
apex and the end of this wire at the base of the carbons, outside of the latter, is
connected with a wire from the generating apparatus and thus a continuous current
of electricity on the outer and inner walls of the carbons is obtained. I may in
some cases, instead of using a spiral conductor, electrotype the inner lining or walls
of the channel through which the air passes. The quantity of air admitted
through the centre of the carbon is regulated by the amount of combustion at the
apex of the pole. By reason of the current of moist air passing through the
centre, the ashes of the carbon are cast off and the carbon is kept comparatively
cool. The point of the wire spiral at the top of the carbon, or the electric lining,
gives increased electric force and forms a steady glow while burning the oxygen
of the air as it passes through the channel in the carbon. By this continued
current of electricity on the inner and outer walls of the carbon complete com.
bustion is perfected.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Andrew Smith Church in the Great Seal Patent Office on the
16th October 1882.
:
ANDREW SMITH CHURCH, of San Francisco, California, United States of
America, now of Wellington Road, St. John's Wood, in the County of Middlesex,
"IMPROVEMENTS IN ELECTRIC LAMPS A communication from abroad by John
B. King, of Brooklyn, New York, United States of America,
"
Heretofore in electric arc lamps both solid and tubular carbons or electrodes
have been used, but in either case the combustion has been more or less imperfect,
and by reason of the ashes or unburned carbon the light has been flickering and
unsteady..
The objects of the present invention are to keep the carbons clean; to increase
the steadiness and brilliancy of the light; to equalize and intensify the combustion
of the carbons; and to cause the carbons to last longer than heretofore.
In carrying the said invention into practice I combine, with a hollow carbon or
electrode, a piece of moist sponge or similar substance through which atmospheric
air may pass to the arc, and I provide an electric conductor, passing through the
carbon or electrode, all as hereinafter described.
In the accompanying drawing are represented two forms or modifications of the
said invention.
Figure 1 is a vertical central section of a carbon or electrode having the sponge
suitably attached thereto.
Figure 2 is a vertical central section showing the sponge fixed in the clamp, into
which the carbon or electrode is inserted, and
Figure 3 is a plan of the same
A is the carbon or electrode having the central aperture or channel B extending
longitudinally through it, and C is a spiral wire within the same extending the
entire length of the said carbon or electrode.
In Figure 1, D is a tube or cap attached to the base of the carbon and con-
taining a piece of sponge E (or similar substance) which is covered by wire
gauze F. In the cap D is an aperture that allows air to enter beneath the sponge
whence it may pass through the sponge to the carbon.
In Figure 2, the sponge E and the wire ganze F are arranged within the
ordinary clamp which holds the carbon or electrode A, the latter being inserted
in the said clamp in the usual manner. This arrangement obviates the necessity
for removing the sponge and wire gauze when it is required to insert a new carbon
or electrode.
The lower end of the spiral wire C passes through the hole or aperture in the
cap D or clamp G to the outside thereof and is connected with the source of
electricity. In some cases instead of forming the internal conductor of a spiral
wire as shown, I form it by electro-plating the inner wall of the carbon or
electrode.
The sponge is to be kept moist. Usually the lamp will be self supplying in respect
of moisture by the chemical union of the hydrogen and oxygen effected by combustion
or by the action of the electric current. The quantity of air passing through the
carbon is regulated by the intensity of combustion and the moist air has the effect
of casting off the ashes.. By means of the internal conductor terminating at the
arc I am enabled to utilize the electric force more completely than has heretofore
been practicable and thereby to render the light steadier and to equalize and
intensify the combustion of the carbons or electrodes.

page_text: A lamp fitted with these improved carbons burns steadily without the usual
singing noise experienced with lamps having the ordinary carbons fitted therein
and with more equal and intense combustion of the two electrodes than has
heretofore been attained.
Having thus fully described the said Invention as communicated to me by my
Foreign correspondent and the manner of performing the same I wish it understood
that I claim, in an electric arc lamp :-
:-
First, The combination, with a tubular carbon or electrode, of a spiral or other
conductor passing through the same, substantially as, and for the purpose,
set forth.
Second, The combination, with a tubular carbon or electrode, of a piece of
sponge or similar substance through which atmospheric air may pass to the arc,
and with or without the wire gauze, substantially as, and for the purpose
set forth.
In witness whereof I the said Andrew Smith Church have hereunto set my
hand and seal this Sixteenth day of October in the year of our Lord One
thousand eight hundred and eighty two.