Improvements in Materials for Incandescing Mantles, and Processes for Manufacturing the same.
Year: 1896

page_text: Date of Application, 4th Aug., 1896-Accepted, 5th Sept., 1896
COMPLETE SPECIFICATION.
Improvements in Materials for Incandescing Mantles, and Processes
for Manufacturing the same.
I, WILLIAM LAWRENCE VOELKER, of Elizabeth, in the County of Union,
State of New Jersey, U.S.A., Electrician, do hereby declare the nature of my
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
My invention relates to improvements in materials for incandescing mantles and
processes for manufacturing the same.
In the first place, the invention consists in a new incandescing material, and the
same consists of an intimate union or combination of two or more of the alkaline
metals or metals of the earths proper, in the proportion of their chemically
combining weights; and this union produced by the action upon an intimate
mixture of the ingredients in such proportions of intense heat, such as that in an
electric furnace.
Preferably the material is such a union as described of calcium and magnesium
and which I term "magnesium calcite," and it may contain a small percentage or
trace of other substances to vary the tint of the light.
In the drawing which accompanies the specification, I have shown a vertical
section of an electric furnace for fusing the ingredients.
The material is prepared in the following manner :-
Suitable salts of the selected alkaline metals or metals of the earths proper, which
are soluble in water and are easily decomposed by heat, such as the nitrates, are
thoroughly mixed together in a finely powdered condition and in the proportions of.
their chemically combining weights. For example, for making the "magnesium
calcite," one hundred and sixty-three and seven tenths (163-7) parts by weight of
calcium nitrate and one hundred and forty-eight and two tenths (1482) parts by weight
of magnesium nitrate are taken. These are ground fine, mixed and then dissolved
together in distilled water. The solution should be made with the minimum
quantity of water that will serve the purpose. When the nitrates have been
dissolved, the solution is evaporated in a suitable vessel heated up to a temperature'
sufficient for the decomposition of the nitrates. The decomposition is completed at "
a red heat. The mass which results is an intimate mixture or union of the oxides
of calcium and magnesium and which will produce a pure white light.
If it is desired to give a yellow tinge to the light, a small proportion, or trace,
say one eighth of one per cent., of cerium nitrate is added to the powdered
substances and dissolved and evaporated with them as described, or if a ruddy tinge
is desired, the same quantity of chromium nitrate is added and treated as before
described. The result in all cases is an intimate union or admixture of the oxides
of the several ingredients.
After evaporation the mass is transferred to a furnace composed of pure calcium
oxide and is therein fused by the electric arc or other means.
Referring to the aforesaid drawing:-
A is the furnace of pure calcium oxide set in a frame B. D D are the terminals
of pure carbon connected with electric circuit wires in any usual manner, and
between which carbons the arc is formed. Said terminals D D are inserted through

page_text: suitable boles in the furnace A and frame B, and may be insulated in any suitable
manner. The mass-resulting from the previous steps of the process is broken into
lumps E, which are fed into furnace from the top. As the material fuses it runs
into the lower part F of the furnace and out by the openings fc and into suitable
vessels or moulds. When it is not desired to mold the material, it is simply
allowed to cool into a large lump or cake.
Now the operation of fusion forces the particles or molecules of the substances
into a most intimate union and results in the new incandescing material; to which,
as hereinbefore stated, in the case of the magnesium and calcium, the term
"magnesium calcite," is applied.
This lump or cake is next ground to an impalpable powder and is then combined
with suitable viscous materials to produce a tough mass, in the following
manner:
A mixture is formed which consists of one part camphor and two parts gun
cotton by weight. These are dissolved in forty times their weight of oil of cassia.
To the solution are added drop by drop, four parts by weight of the strongest
sulphuric acid, the solution being constantly stirred as the reaction takes place.
The completion of the reaction is indicated when the whole has doubled its bulk.
Then the solution is cooled to normal temperature. The cooled mass has a viscous
constituency, and is used in the proportion of one part by weight to three parts by
weight of the powdered magnesium calcite. This powder is then mixed into the
viscous mass, and then thoroughly incorporated with it by passing the whole
between hot rolls. This rolling not only thoroughly incorporates the chemicals
with the viscous mass, but also consolidates and toughens the product. After being
thoroughly rolled, this product is put in a metallic vessel or chamber, pressed with
great pressure, and while being pressed is heated to a temperature of about 110° F.
for twenty-four hours, more or less. The final product is very tough and can be
rolled into sheets or drawn into threads, as through dies. The sheets may be
perforated and formed into mantles, or the threads can be knitted to form them.
The viscous material carbonizes when the mantle is burned out and there is left a
mantle consisting of the oxides of the chemicals that were used.
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 1.
claim is :-
1. A material for use in making incandescing mantles and consisting of a fused
mass of several metallic oxides in the proportions of their chemically combining
weights, substantially as described.
2. A material for use in making incandescing mantles, consisting of the oxides of
magnesium and calcium, first combined in the proportions of their chemically
combining weights and then fused at high temperatures; substantially as
described.
3. A material for use in the manufacture of incandescing mantles, and consisting
of several light-giving metallic oxides and color producing metallic oxide all
combined in the proportions of their chemically combining weights and fused at
high temperatures, substantially as described.
4. The process of manufacturing materials for producing incandescence herein-
before described, consisting in mixing several of the incandescible metallic salts in
the proportions of their chemically combining weights and then heating the
combined materials to a high temperature, substantially as described.
5. The process of manufacturing materials for producing incandescence herein-
before described consisting in mixing several of the incandescible metallic salts and
color producing metallic oxide all in the proportions of their chemically combining
weights and then heating the whole to a bigh temperature, substantially as
described.
6. A material for the manufacture of incandescents consisting of the oxides of

page_text: several of the incandescible minerals combined and fused in the proportions
of their chemically combining weights and a viscous carbonizable joining material,
substantially as described.
Dated this 4th day of August 1896
S. S. BROMHEAD,
97 Newgate Street, E.C., Patent Agent.