Year: 1887

page_text: Date of Application, 6th Dec., 1887
Complete Left, 2nd Jan., 1888
Complete Accepted, 10th Feb., 1888
I CHARLES FREDERICK HENGST of 20 Burwash Road, Plumstead in the County
of Kent, Engineer do hereby declare the nature of this invention to be as follows:-
:-
My invention relates to the manufacture of a novel explosive compound which is
extremely rapid in its explosive action and is entirely smokeless.
In carrying out my invention I proceed as follows:-I take a given quantity of
pulped straw preferably oat straw-and treat said pulped mass with nitric and
sulphuric acids of a certain specific gravity, and reduce the excess of temperature
occasioned by the chemical combination of the acids and pulp aforesaid by adding
sufficient water.
.The above described treatment having been properly accomplished, I subject the
resultant mass to about 60 hours continuous washing in running water, that is to say,
until such time as litmus or other acid tests fail to indicate the slightest traces of acid
in the material under treatment; whereupon, the latter may then be preferably
stamped, pressed or moulded into the form of wads,-or, same may be formed into
granules, having an explosive power six times in excess of that possessed by the
same volume or quantity of the explosive powder known generally as nut" powder
used for heavy ordnance.
<
The explosive produced in accordance with my Invention is perfectly safe to handle
in the process of manufacture or in the course of transit, inasmuch as it cannot be
ignited by percussion or friction but only by the application of a flame or spark.
..
1007
JAMES STEVENSON,
Gray's Inn Chambers,
20, High Holborn, London, W.C.,
Agent for Applicant.

page_text: I, CHARLES FREDERICK HENGST of 20 Burwash Road, Plumstead, in the County of
Kent, 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 :-
The object of my invention is the production of a gunpowder or explosive
compound which, whilst being very rapid in its explosive action, shall be absolutely
smokeless.
In carrying out the production of the smokeless gunpowder according to my
invention I proceed as follows: that is to say:-
I take a mass of pulped straw-preferably oat straw, as the latter contains less
silica and similar objectionable matter than other carbonaceous material of a like
nature. I treat the above mentioned mass of vegetable fibre with a mixture composed
of two parts by weight of Sulphuric Acid (H,SO) specific gravity 1-850, equivalent
to 66° Baume and one part by weight of Nitric Acid (HNO3) specific gravity 1-486,
equivalent to 46° Baumè. The pulp being allowed to macerate in this acid mixture
for a period of from 15 to 20 hours, the resultant chemical action causes a rise of
temperature in the mass during maceration, and I prefer to maintain said temperature
at 180° Fahrenheit; reducing it, should it exceed the above mentioned limit, by the
addition of cold water.
As an alternative method to the above I may carry out the process of maceration
in a vessel provided with a surrounding jacket filled with water which is caused to
circulate by any suitable means, and so regulates the temperature of the vegetable
fibre during the process of maceration without the necessity for mingling water
with it.
When the macerating process has been sufficiently advanced, I strain off the acids
from the pulp, and subject the latter to a continuous washing in running water for a
period of from 40 to 60 hours, until litmus exhibits no change, when applied as a
test, thereby indicating that no trace of acid remains. I then steep the whole mass
in a solution of hyposulphite of soda or other suitable alkaline solution, and allow it
to dry slowly by exposure to a current of dry air. When thoroughly dry it may be
compressed, and stamped cut or otherwise formed into wads, cubes, granules or other
suitable shapes, and is then ready for use.
In order to regulate the rapidity of combustion during explosion, 1 may add at the
beginning of the process hereinbefore described a certain quantity of ligneous fibre
other than the straw fibre above mentioned in direct proportion to the required
retardation of the explosion.
The resultant compound when dried and formed according to my invention cannot
be exploded by friction or percussion, but by ignition only, by the application of a
flame, spark or red heat, and thereby possesses the advantage over other explosives,

page_text: that there is no danger to life or property during the process of manufacture, during
transport, or by the stowage thereof in magazines or other receptacles.
When used as an explosive in a cartridge or other convenient manner, the
combustion during explosion is rapid and perfect, so that no smoke is evolved,
rendering it particularly applicable to rapid firing machine or magazine guns.
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 what
I claim is
The smokeless gunpowder or explosive compound prepared in the manner
substantially as herein described.