IMPROVEMENTS IN THE MANUFACTURE OF EXPLOSIVES
Year: 1876

page_text: LETTERS PATENT to Samuel Joseph Mackie, Camille Alphonse Faure, and
George Trench, all of Faversham, in the County of Kent, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF EXPLOSIVES."
PROVISIONAL SPECIFICATION left by the said Samuel Joseph Mackie,
Camille Alphonse Faure, and George Trench at the Office of the Commissioners
of Patents on the 4th July 1876.
SAMUEL JOSEPH MACKIE, CAMILLE ALPHONSE FAURE, and GEORGE.TRENCH, all of
Faversham, in the County of Kent. "IMPROVEMENTS IN THE MANUFACTURE OF
EXPLOSIVES."
This Invention has for its object improvements in the manufacture of explosives.
For this purpose esparto grass, such as used for paper making, or hemp, flax,
straw, hay, jute, the leaves and stems of the agave, yucca, and pine apple, the fibre ot
the cocoa nut husk, and of the leaves of the various varies of the palm, rags jor
paper pulp, and wood fibres generally are first purified by boiling with caustic
alkalies and afterwards decoloured by chlorine, as in the manufacture of paper,
these materials are then to be converted into nitro-cellulose by immersion in mixed.
nitric and sulphuric acids according to the known process, for making gun cotton,
or as practised in the manufacture of Shultze and Muschamp's powders.
When the esparto or wood and other fibres are thus converted into nitro-cellulose
we purify or otherwise well wash the pulp to make it pure, and mix it thoroughly
with its own weight about of nitrate of baryta, and while still in a damp state. we
mould this mixture into compact and dense charges, which we afterwards put to
dry. These charges have a central hole to receive a detonating cap when they are
to be fired.
In order to protect the charge against rough usage and moisture we cover each
charge with a wrapper of paper or canvas and a coating of paraffin. The paper
wrapper if any
has a neck provided with a length of copper wire or string to fasten
the capped fuse into the central hole of the charge.
These cartridges or charges are similar to those described in the Specification of
a former Patent granted to us, No. 3612, in the year 1874, with the difference that
whereas in them cotton was used as the base of the explosive charge we now
propose to use esparto or wood fibre or other substances as aforesaid, which are much
[Price 4d]

page_text: cheaper than cotton, but we retain the nitrate of baryta as the principal oxidising
agent, and we use the same form of compressed cartridge.
We propose also to use any known oxidising agent in combination with the
nitro-cellulose prepared as above and the shape of compressed and waterproof
charge as aforesaid.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said Samuel Joseph Mackie, Camille Alphonse Faure, and George Trench in the
Great Seal Patent Office on the 4th January 1877.
SAMUEL JOSEPH MACKIE, CAMILLE ALPHONSE FAURE, and GEORGE TRENCH, all
of Faversham, in the County of Kent. "IMPROVEMENTS IN THE MANUFACTURE OF
EXPLOSIVES."
This Invention has for its object improvements in the manufacture of explosives.
For this purpose esparto grass, such as used for paper making, or hemp, flax,
straw, hay, jute, the leaves and stems of the agave, yucca, and pine apple, the fibre
of the cocoa nut husk, and of the leaves of the various varieties of the palin, rags or
paper pulp, and wood fibres generally are first purified by boiling with caustic
alkalies, and afterwards decolored by chlorine, as in the manufacture of paper.
These materials are then to be converted into nitro-cellulose by immersion in mixed
nitric and sulphuric acids, according to the known process for making gun cotton
or as practiced in the manufacture of Schultze and Muschamp's powders.
When the esparto or wood and other fibres are thus converted into nitro-
cellulose we purify or otherwise well wash the pulp to make it pure, and mix it
thoroughly with its own weight about of nitrate of baryta, and while still in a
damp state we mould this mixture into compact and dense charges, which we after-
wards put to dry. These charges have a central hole to receive a detonating cap
when they are to be fired.
In order to protect the charge against rough usage and moisture we cover
each charge with a wrapper of paper or canvas and a coating of paraffin. The paper
wrapper if any has a neck provided with a length of copper wire or string to fasten
the capped fuse into the central hole of the charge.
These cartridges or charges are similar to those described in the Specification of
a former Patent granted to us, No. 3612, in the year 1874, with the difference that
whereas in them cotton was used as the base of the explosive charge we now
propose to use esparto or wood fibre or other substances as aforesaid, which are much
cheaper than cotton, but we retain the nitrate of baryta as the principal oxidising
agent, and we use the same form of compressed cartridge. We propose also to
use any known oxidising agent in combination with the nitro-cellulose prepared as
above and the shape of compressed and waterproof charge as aforesaid.
In order that our said Invention may be most fully understood and readily carried
into effect we will proceed to describe the way of proceeding to obtain these charges
of explosive when wood is the material employed.
Pieces of wood, such as pine wood, are put into a grinding machine and re-
duced to a fine state of division with water. The pulp thus obtained is introduced
in a large closed cast-iron vessel, and there subjected to a high temperature in a
lye of caustic soda. This stuff is then turned out of the vessel, strained, and put
upon shelves in a room into which chlorine gas is admitted until the coloring
matter has disappeared, after which the stuff is washed in water and dried
thoroughly.
To convert this material, which is now pure cellulose, into nitro-cellulose we
agitate it for one hour or more in a bath of mixed strong nitric and sulphuric acids
in the proportion of three parts of sulphuric and one part of nitric acid.
The nitro-cellulose is subsequently strained in a centrifugal machine, and washed
until free from any adhering or uncombined acid or other impurities, and in the

page_text: same manner as is done in the well-known processes of washing gun cotton. When
the nitro-cellulose is thoroughly pure it is mixed while containing yet about thirty
per cent. of water with its own weight of nitrate of baryta, and the two are well
incorporated in a mill fitted with edge runners.
We make this compound into charges by filling metallic moulds with a weighted
quantity of the compound, and subject it by means of a piston under a powerful
press to a high pressure sufficient to cause the charge to hold together in the desired
form, which may be prismatic or cylindrical. The charge is then put to dry in a
current of hot air. The piston of the pressing machine is fitted with a short peg
which leaves in the moulded charge a corresponding small cylindrical hole, which
is intended for the lodgement of the capped fuse when the charge will require to be
exploded.
After the moulded charges are dried they are dressed with a sheath of paper or
canvas, or any other such protecting material, and this covering is arranged in the
form of a neck above the central fuse hole and around the neck, and fastened
thereto is a piece of wire or string which will subsequently serve to make the fuse
fast to the cartridge so as to facilitate the loading of mines and preventing the
separation of the fuse from the charge. In order to protect the charges especially
against water they are finally dipped in melted paraffin; they are then ready for
use. Finally, what we claim as our Invention is-
First. The incorporation by admixing machinery of nitro-cellulose manufactured
as described with nitrate of baryta.
Second. The moulding into the shape described of nitro-cellulose mixed with
nitrate of baryta or any oxidising agent, and covering and waterproofing the charges
thus obtained, substantially as described.
In witness whereof, we, the said Samuel Joseph Mackie, Camille Alphonse
Faure, and George Trench, have hereunto set our hands and seals, this
Thirtieth day of December, in the year of our Lord One thousand eight
hundred and seventy-six.