Improvements in the Manufacture of Pyrotechnic Compounds.
Year: 1895

page_text: Cate of Application, 24th Dec., 1895-Accepted, 25th Jan., 1896
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Pyrotechnic Compounds.
I, WILHELM WEIFFENBACH of Pyrotechnical Works, Heidersklinge,
Carlsvorstadt Stuttgart in the Empire of Germany, Pyrotechnist, 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 process which forms the object of this invention is designed to produce a
slow and evenly burning innocuous spark-producing pyrotechnic compound, any
addition of oxygen containing substances such as nitrates or chlorates being avoided
by the use of combustible substances and metallic powders which are mixed in
suitable quantities to combine with oxygen from the air in a form in which
similarly to the aforesaid oxygen containing substances hitherto employed, it
supports and accelerates the combustion of the organic substances employed as
thickening and binding materials, which latter in themselves burn but slowly.
The following mixture has been found by means of thorough experiments to be
an extremely suitable one for the object designed, and more particularly for the
production of the desired effect similar to the play of electric sparks.―
Potato starch
Dextrin
Gum arabic
Powdered charcoal
Pine soot
Magnesium powder
Steel filings
250-300 parts.
100-110
"
50-
- 60
..
"
38
1
- 40
"
_
38
75-100
200
40
"
"
» (may also be omitted).
Any considerable departure from these carefully tested proportions of mixture
makes the result absolutely uncertain.
The above mixture is worked up with water into a thick even paste and allowed
to stand in a cool airy place until the following process has been completed.
First, a sort of fermentation takes place, which mainly consists in the development
of hydrogen. When this is over the mass remains one or two days longer in
It thus absorbs oxygen and
contact with the air, being occasionally stirred.
contains finally (especially in dried condition) considerable quantities of oxygen in
an active form, probably as magnesium super-oxide. The combination of active
oxygen is particularly assisted by the use of steel filings in addition to the
magnesium powder. A thoroughly scientific explanation of this circumstance
5 cannot at present be given, but without doubt the porosity of the carbon and the
pine soot play an important part in the absorption of oxyger.
After the mixture has stood the necessary time and has assumed a right
consistency, it is employed in a suitable form in the body of the firework, which
is to be made, or by placing on it wooden sticks in the manner of Bengal matches,
Oor in other suitable manner. When it has become dry the mass may be ignited by
being brought into contact with a flame, and it will then burn slowly, developing
only very little flame and smoke, and leaving behind a small quantity of loose,
non-smouldering, white ash, whilst constantly ejecting white radiating simple, and
if steel shavings be added, also yellow. star-shaped sparks. If these sparks come
5 into contact even with easily inflammable articles, they leave the same quite

page_text: intact, and only produce on the hand a slight warm sensation. The igniting of
the firework may take place by combining it with a substance ignited by friction,
or with a fuse instead of igniting it by contact with a flame.
The treatment of the mixture herein before described is, for obtaining a correct
result, equally as important as the composition of the mixture itself.
The principal difference of this process from those hitherto employed appears
sufficiently from what has been hereinbefore stated as regards the mixture and its
treatment.
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 process for the manufacture of a pyrotechnic compound to produce a play
of electric sparks, consisting in the employment and treatment of materials
substantially as herein before described, whereby nitrate, chlorate and the other
oxygen-containing substances hitherto employed are dispensed with, and replaced
in their action by active oxygen, which during the process is itself absorbed from
the atmosphere by the materials and is combined in the form probably of magnesium
super-oxide.
2. A pyrotechnic compound formed by the employment and treatment of
materials substantially as hereinbefore set forth.
Dated this 23rd day of December 1895.
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Agents for the Applicant.