Improvements in Magnesium Lights for Photographic and Signalling Purposes.
Year: 1891

page_text: Date of Application, 2nd May, 1891-Accepted, 19th Dec., 1891
COMPLETE SPECIFICATION.
Improvements in Magnesium Lights for Photographic and Signalling
Purposes.
I EUGEN HACKH of Stuttgart (31 Konigstrasse) in the German Empire,
Photographer, 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 :-
The present invention relates to the production of magnesium light for photo-
graphic and signalling purposes and its object is to achieve a complete utilization
of the entire illuminating power of magnesium powder, by preventing the particles
of the same from remaining in close contact with each other, i.e. loosening the same
so that the oxygen of the air may have access to each and every particle of the
powder.
By this means I attain the result that every particle of the magnesium powder
is brought to a white glow, producing the effect of an intense perfectly white
flame.
I effect the separation of the particles of the magnesium powder by thoroughly
mixing or combining the same with some fibrous material. Long, carded, unspun
wool is preferably employed for this purpose, the fibres or threads of which said
wool should cross each other to form a sort of net.
In order to attain a good adhesion of the particles to the wool, the latter should
be soaked in a mixture of 2 parts vegetable oil, 2 parts benzine and 1 part Venice
turpentine, it should be then wrung or pressed out and dried, to such an extent that
the wool retains a thin oily coating not sufficient to be visible but just enough to
be slightly felt.
The magnesium powder is then shaken over the wool, or other suitable fibrous
material thus prepared, and kneaded, or treated in other suitable manner, until the
threads or fibres of wool are thickly covered with particles of the powder. The
oxygen necessary for combustion will now have easy access to each and every one
of the particles of magnesium thus arranged or deposited on the fibres or threads.
The fibres thus covered with powder can then be twisted together like a rope to
concentrate the source of light and the twist coiled to a spiral. The amount of
light produced will vary with the diameter and length of the twisted fibres whilst
the duration and intensity of the light may be regulated by twisting the fibres or the
coil more or less tightly. If for instance the coil is wound and twisted tightly,
the light produced will last. longer, but have less illuminating power; if loosely
wound the illuminating power will be greater but the duration shorter.
The magnesium coils should be preferably burnt in an apparatus, in which the
light produced by the explosive combustion of the particles of magnesium can be
concentrated to one point or in one direction.
For this purpose the coil can be mounted on a coarse meshed wire netting which
is stretched over a concave metal plate and on which a funnel shaped casing having
both ends open is arranged. Such casing causes the glowing particles of magnesium
to be thrown out in the form of a cone, so that in the open space, sufficient oxygen
having access to the particles, a perfect combustion of the same at a white glow
heat takes place.
By this means every particle in burning will give off its full illuminating power.
The accompanying drawing represents in:-
Fig. 1 the arrangement of a magnesium light cartridge in a light distributing
cone carried by a suitable frame or support and adapted for photographic purposes,
in Fig. 2 an elevation of the light cartridge, in Fig. 3 a section of Fig. 2, and in
Fig. 4 a piece of the braids of which the cartridge is composed.

page_text: The braids a are preferably wound in spiral form and inserted in an appropriate
disc with conical rim c.
is
The employment of this magnesium light cartridge for photographical purposes
is represented in Fig. 1, in which the light distributing cone is used which is carried
by the support or frame e, said frame having joints, so that when the hook
released from the eye the rods e¹ can be lowered and with these the cone d in
order to facilitate the insertion of a cartridge into the said cone d. No special
device for igniting the cartridge has been represented as this can be effected in very
many ways, by means of an electric spark, direct flame, or in any other appropriate
manner.
The apparatus above mentioned also enables the direction of the light to be
altered in any desired manner, as the plate supporting the illuminating coil together
with the funnel or other shaped casing may be revolved, and if desired easily
so arranged that the illuminating coil may be adjusted in the vertical plane.
A magnesium light of the kind described can be used for photographic purposes,
as also for signalling purposes of every description at sea and for field purposes, as
also for various other purposes where a very intense, white and eventually
enormously powerful light is of importance.
The illuminating coils can be made in any variety of size and form according to
the purpose for which they are designed; packed in suitable manner the same will
last any length of time, they are easy to manipulate and the fibrous matter burns
entirely, leaving no residue whatever.
Having now particularly described and ascertained the nature of my said inven-
tion and the manner in which the same is to be performed I declare that what I
claim is :
1. A magnesium light for photographic and signalling purposes in which the
particles of the magnesium powder are held apart to facilitate the access of the
oxygen to the same, on combustion, consisting of the combination with the magnesium
powder of a fibrous material to which the same is caused to adhere substantially as
described.
2. Twisting the combined powder and fibrous material together into rope or
other form and winding the same to a coil for the purpose substantially as
described.
3. Soaking or impregnating the fibrous material previous to its combination with
the powder, in or with a mixture of vegetable oil, benzine and Venice turpentine
and drying the same to the extent described, said mixture being in or about the
proportions as hereinbefore described.
4. The magnesium light and manner of producing and mounting the same
substantially as herein before described.
Dated 2nd day of May 1891
PHILIP M. JUSTICE,
Associate Agent.