Year: 1896

page_text: Date of Application, 25th Jan., 1896
Complete Specification Left, 24th Oct., 1896-Accepted, 12th Dec., 1896
I, PETER STIENS of 62 Leyton Park Road Leyton in the County of Essex,
Engineer do hereby declare the nature of this invention to be as follows:-
According to this invention magnesium chloride which has been heated to a high
temperature and then cooled is ground and mixed with a small quantity of powdered
burnt chalk and gum tragacanth or gelatine. The mixture is made into a paste
and passed into a mould to the desired form.
When dry the mantle is sprayed over with a solution of unburnt magnesium
chloride and subjected to a high temperature in a furnace.
Dated this 25th day of January 1896.
I, PETER STIENS late of 62 Leyton Park Road Leyton in the County of Essex
now of 9 Chilsham Road Clapham in the County of Surrey Engineer, 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 :-
According to this invention magnesium chloride which has been heated to a high
temperature and then cooled and ground is employed in the manufacture of
incandescent mantles.
The magnesium chloride should be burnt in an open vessel over a flame or in a
furnace until it is reduced to a uniform white mass.
The material resulting mixed with about 2 to 3 per cent. of powdered burnt
chalk and sufficient gum tragacanth or gelatine to form a paste with water and
passed into a mould to the desired form but preferably the mantle is made in the
usual way by impregnating threads or a woven material with a solution containing
about one part of the burnt magnesium chloride in two parts of nitric acid. A
part of the magnesium chloride may be replaced by zirconium.
In either case the mantle is dried and burnt and then sprayed over with a
solution of burnt or unburnt magnesium chloride and with or without calcium
oxide or carbonate and finally again exposed to a high temperature.
The addition of burnt magnesium chloride also improves mantles made from
other ingredients such for example as the well known thorium mantles.
The addition may be made by simply spraying dipping or otherwise covering
with a solution of burnt magnesium chloride, with or without calcium oxide and
carbonate, the finished mantle but I prefer also to add burnt magnesium chloride
in the process of manufacture.
Thus I employ a mixture of about 50 to 80 per cent. of burnt magnesium chloride

page_text: and 20 to 50 per cent. of thorium in the ordinary process of making the mantle by
impregnating threads or woven material, I then burn and spray over with a weak
solution of burnt or unburnt magnesium chloride with or without calcium oxide or
carbonate.
In this way I obtain greater luminosity and strength.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that I wish it
to be understood that I am aware that it has before been proposed to use magnesium
chloride in incandescent mantles and I do not claim the use of this ingredient
unless it has been exposed to a high temperature before the manufacture of the
mantle but what I claim is :-
The employment in the manufacture of incandescent mantles of magnesium
chloride which has first been exposed to a high temperature substantially as
described: