Improvements in the Manufacture of Gunpowder.
Year: 1891

page_text: Date of Application, 4th July, 1891-Accepted, 8th Aug., 1891
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Gunpowder.
We, CHARLES HERBERT CURTIS of 74 Lombard Street in the City of London,
Gunpowder Manufacturer and GEORGE GUILLAUME ANDRÉ of Havelock
Cottage, Dorking in the County of Surrey, Civil 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:-
Heretofore nitrocellulose either in the soluble form (as dinitro-cellulose) or in
the insoluble form (as trinitro-cellulose) has been used in combination with nitro-
glycerine as an ingredient in explosives for blasting purposes and more recently in
smokeless gunpowder.
Now we have discovered by a series of experiments extending over a long period
of time that a mixture during manufacture of the insoluble with the soluble
varieties of nitrated cotton in certain proportions say about 2 of the former to 1
of the latter forms a base which in combination with nitroglycerine gives a product
differing materially in its physical qualities from those obtained from the use of one
variety of nitrated cotton alone, and one which is more suitable as a gunpowder.
This our product is translucent, tough and leathery, and in use, practically
smokeless. A suitable base is obtained by mixing 40 to 47 parts by weight of the best
insoluble nitrated cotton and from 20 to 23 parts of the best soluble nitrated cotton
for the nitro-cellulose base, which is as a suitable example combined with from 30
to 40 parts of nitro-glycerine together with about 50 to 60 parts of acetone or
acetic ether as a solvent. The manufacture is by preference carried on at the
ordinary temperature. The gelatinous mass resulting from a sufficient kneading of
The solvent having
the compound may then be granulated by the usual means.
evaporated the material is ready for use.
With the ingredients named we may also incorporate suitable material in small
proportions for modifying the explosiveness and for protecting against atmospheric
influences, such as paraffin, shellac or graphite. We find that a small proportion
of ordinary gunpowder gives excellent results in this respect though producing a
slight smoke.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that we are
aware of the Specification No. 12338 of 1889, and make no claim to what is
therein described and claimed. Nor do we claim the manufacture of explosives
from either insoluble nitrocellulose alone or soluble nitrocellulose alone or from
anything other than a base produced by mixing during manufacture insoluble
nitrocellulose with soluble nitrocellulose in or about the proportions named; but
what we claim is :-
1. The manufacture of smokeless gunpowder consisting of a nitro-cellulose base
made by mixing soluble and insoluble nitrated cotton in combination with nitro-
glycerine in or about the proportions named and with or without modifying agents,
substantially as set forth.
2. In the manufacture of nitro-glycerine explosives suitable for fire-arms, the

page_text: application and use of soluble nitro-cellulose mixed with insoluble nitro-cellulose
in or about the proportions named substantially as set forth.
Dated this 4th day of July 1891.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.