IMPROVEMENTS IN ELECTRIC LAMPS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the Office of
the Commissioners of Patents on the 3rd December 1880. A. communication
from abroad by Auguste de Meritens, of Paris, in the Republic of France.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. * IMPROVEMENTS IN ELECTRIC LAMPS." A communication from
abroad by Auguste de Meritens, of Paris, in the Republic of France.
This Invention relates to improvements in the production of light by electricity,
and it consists in the employment of iron rendered incandescent by the passage of
an electric current of high tension, as hereinafter described.
When a sufficient number of electric sparks is caused to pass between the
extremities of two platina wires enclosed in a close chamber and connected to
suitable rheophores or conductors communicating with an induction coil, the said
chamber will soon become filled with nitric and hyponitric acid.
The current supplied to the inductor of the coil may be obtained from a battery
or from a magneto-electric or dynamo-electric machine furnishing a continuous
current. It may likewise be generated by a magneto- or dynamo-electric machine
delivering alternate currents. In the latter case the interrupter and condenser of
the induction coil are dispensed with, and the number of sparks passing between
the extremities of the platina wires in a unit of time is increased; the quantity of
nitric and nitrous acid produced being also augmented at the same time, the
quantity of acid produced by a given number of sparks being greater in proportion
as the tension of the induction apparatus is increased. The same result may be
obtained without an induction coil by employing a magneto or dynamo electric
machine, furnishing alternate currents of a tension equivalent to that of a powerful
induction coil. If the chamber hereinbefore referred to is dispensed with, the
formation of nitric and nitrous acids will still take place under the same conditions
and in the same proportions. When the extremities of the rheophores are connected
with ordinary carbons in lieu of the platina wires, the quantity of nitric and nitrous
acid produced will be diminished by an amount equal to the quantity of carbonic
acid resulting from the combustion of the carbons, but the production of the said
nitric and nitrous acid still continues, and is directly proportional to the tension of
the current, varying (when a current of a given tension is employed) in inverse
proportion to the diameter of the carbon.

page_text: All electric burners, regulators, lamps, or candles, working with an arc effect, a
combination of the oxygen with the nitrogen of the atmosphere.
Now according to this Invention the extremities of the rheophores or conductors
are connected with two iron wires terminating in small balls or spheres of the same
metal, and supported by two supports of insulating material placed upon a table,
and capable of adjustment, so as to enable the distance between the iron balls or
spheres to be increased or diminished as required. Then when an induction current
of high tension, obtained as hereinbefore described, is caused to pass in the
rheophores, and the iron balls are brought to within a short distance of each other,
the following phenomena will be observed, viz.:—
The iron balls will gradually become red hot, and up to this period a succession
of sparks will be seen to pass between the nearest points of the two balls; the latter
rapidly attain a white heat, and soon after reach a state of dazzling incandescence.
The iron does not melt and is not consumed; there is not the slightest indication
of the passage of any more sparks, and the light continues as long as the current
passes.
If the current is now shut off and the iron balls are subsequently
examined under a magnifying glass, it will be found that their surface is bright
and smooth, and has not been in the least affected by the nitric acid.
The heat of the balls continues from the points which are opposite to and nearest
to each other, where it is at its maximum, to about half way round the balls or
spheres, where it is at its minimum. The iron is liquified at the points which are
nearest to each other, and is held up by attraction to the surface of the sphere. The
continued presence of nitric and nitrous acid renders it passive, so that it is not and
cannot be decomposed or consumed.
The amount of molecular transposition or transference from one pole to the other
is consequently infinitely small, and in fact scarcely perceptible.
Any suitable number of small balls supported on iron rods may be arranged near
together in a line, instead of employing two only, as herein before described, the
two end balls being connected with the rheophores or conducting wires. Then,
when the current passes, all the balls in the line will become incandescent, and
will produce a light of absolute steadiness so long as the current passes. The
apparatus may be modified in its details whilst still retaining the principle of this
Invention.
By means of this Invention it is possible to obtain lights of any degree of
illuminating power, from, say, half the illuminating power of an ordinary stearine
or composite candle to that of a hundred gas jets and upwards. The light may
be lighted and extinguished as often as required by simply moving a commutator."
The burner requires no attention either for its adjustment or for changing the
combustible.
The cost of constructing the improved lamp is exceedingly small, and that of its
maintenance perfectly insignificant.