An Improved Composition for Increasing the Illuminating Power of Electric Arc Lamps.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
An Improved Composition for Increasing the Illuminating Power
of Electric Arc Lamps.
I, PAUL MERSCH, of 21, Boulevard Poissonniere, Paris, in the Republic of
France, Doctor of Law, do hereby declare the nature of this invention to be as
follows:-
This invention relates to a chemical composition intended for the manufacture
of mantles or blocks of any description whatever applicable for use with electric arc
lamps with the object of increasing their illuminating power.
The composition is obtained in the form of a paste by the admixture of the
substances enumerated below. This paste, owing to its composition, possesses the
following properties; it is absolutely incombustible and hardens more and more
under the influence of heat; it may be rendered incandescent at the highest as well
as at the lowest temperatures without becoming deteriorated or volatilised.
The paste may be fashioned into all kinds of forms applicable for electric arc
lamps. For example, mantles may be made serving to surround the carbons of
arc lamps at the luminous point, or reflectors, blocks intended to be interposed
between the two luminous points of the lamp carbons, tubes completely surrounding
these carbons; in short this paste may be worked into any form requisite or
desirable for the purpose of its use with the object of obtaining the result aimed at,
that is to say of imparting to voltaic arc lamps the greatest possible illuminating
power.
The chemical composition of the paste intended to be used in the above manner
is as follows:
Approximately equal parts of each of the three following bodies are taken and
mixed together.
1st. Carbonate of magnesia..
2nd. Asbestos or any other kind of incombustible fibre.
3rd. Silicate of potash.
The combination of these three substances gives an homogeneous paste, capable
of taking any suitable form, hardening under the action of heat whilst at the same
time it is raised to incandescence.
Dated this 11th day of March 1897.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
An Improved Composition for Increasing the Illuminating Power
of Electric Arc Lamps.
I, PAUL MERSCH, of 21, Boulevard Poissonniére, Paris, in the Republic of
France, Doctor of Law, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
This invention relates to a chemical composition intended for the manufacture
of mantles or blocks of any description whatever applicable for use with electric
are lamps with the object of increasing their illuminating power.
The composition is obtained in the form of a paste by the admixture of the
substances enumerated below. This paste, owing to its composition, possesses the
following properties; it is absolutely incombustible and hardens more and more
under the influence of heat; it may be rendered incandescent at the highest as well
as at the lowest temperatures without becoming deteriorated or volatilised.
The paste may be fashioned into all kinds of forms applicable for electric arc
lamps. For example, mantles may be made serving to surround the carbons of
are lamps at the luminous point, or reflectors, blocks intended to be interposed
between the two luminous points of the lamp carbons, tubes completely surrounding
these carbons; in short this paste may be worked into any form requisite or
desirable for the purpose of its use with the object of obtaining the result aimed at
that is to say of imparting to voltaic arc lamps the greatest possible illuminating
power.
The chemical composition of the paste intended to be used in the above manner
is as follows:
The three following bodies are taken and mixed together.
Carbonate of magnesia, asbestos or any other kind of incombustible textile
product and silicate of potash or silicate of soda.
The combination of these three substances gives an homogeneous paste, capable
of taking any suitable form, hardening under the action of heat whilst at the same
time it is raised to incandescence.
The mantles are made in the following manner:
A very intimate mixture (for every 10 parts) is made by kneading with 1 part
asbestos, cut into very fine, small pieces, 2 parts of silicate of soda or of potash (this
product is obtained in a liquid state by heating the flakes of silicate in a water-bath
the density of this liquid is 1 kg. 250 grms. per cubic decimeter).
Seven parts of carbonate of magnesia are then added. These various bodies being
suitably kneaded, they are submitted to strong pressure in a mould for that
purpose, by means of a press. They are placed in a drying chamber for about 8 hrs.,
and are then submitted to a baking process at a temperature of 1200-2000°
Centigrade.
Under the action of the heat of the voltaic are the mantels crystallise, and they
become as hard as glass. The lighting power which they develop is about 30%
more than that of the are, and the duration of the carbons is augmented by more
than 50%.
The mantles manufactured from the above described composition have the
advantage of prolonging the duration of the carbons thereby effecting a considerable
saving in the working of the lamps.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
A chemical composition obtained in the form of a paste by the admixture of

page_text: carbonate of magnesia, asbestos or some other incombustible textile product, and
silicate of potash or silicate of soda, the said paste being capable of taking any form
suitable for its employment with the voltaic are with the object of increasing the
illuminating power of the latter to a very large extent and preserving the carbons
as above described.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.