IMPROVEMENTS IN THE MANUFACTURE OF GUN COTTON
Year: 1870

page_text: LETTERS PATENT to Robert Punshon, of 3, St. Nicholas Buildings,
Newcastle-on-Tyne, Merchant, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF GUN COTTON."
Scaled the 11th April 1871, and dated the 31st October 1870.
PROVISIONAL SPECIFICATION left by the said Robert Punshon at the
Office of the Commissioners of Patents, with his Petition, on the
31st October 1870.
I, ROBERT PUNSHON, of 3, St. Nicholas Buildings, Newcastle-on-Tyne,
Merchant, do hereby declare the nature of the said Invention for
IMPROVEMENTS IN THE MANUFACTURE OF GUN COTTON," to be as follows:-
6
My Invention has for its object the preparation of gun cotton in such
a manner as to diminish and regulate the rapidity of its explosiveness,
and thereby render it suitable for use in guns for military and sporting
purposes and more suitable for blasting.
And my Invention consists in coating, covering, or incorporating
the particles or fibres of gun cotton with sugar, that is to say, with

page_text: either cane, beet, maple, grape, or other sugars, either raw or refined,
or mixtures of the same, but I prefer to use for the purpose refined or
crystallised sugar. For this purpose I dissolve the sugar in water by
means of heat, then add the quantity of gun cotton under treatment,
and keep it in the solution for about twelve hours, more or less, and
afterwards dry it by a centrifugal machine, by pressure, or by heat.
The effect produced on the gun cotton by mixing or combining sugar
therewith is to reduce and regulate (according to the proportion in
which it is employed) the explosive character or quality of the gun
cotton. And in order to aid the development of the explosive force as
may be required I use a flux, by preference Baumé's "flux," or an
explosive such as white or ordinary gunpowder.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Punshon in the Great Seal Patent Office on
the 29th April 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
PUNSHON, of 3, St. Nicholas Buildings, Newcastle-on-Tync, Merchant,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirty-first day of October, in the
year of our Lord One thousand eight hundred and seventy, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Punshon, Her special
licence that I, the said Robert Punshon, my executors, administrators,
and assigns, or such others as I, the said Robert Punshon, my exe-
cutors, administrators, or assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF GUN COTTON," upon the condition (amongst others)
that I, the said Robert Punshon, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, and cause the

page_text: same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Punshon, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement (that is to say):-
My Invention of "Improvements in the Manufacture of Gun Cotton"
has for its object the preparation of gun cotton in such a manner as to
diminish and regulate the rapidity of its explosiveness, and thereby
render it suitable for use in guns for military and sporting purposes, and
more suitable for blasting.
And my Invention consists in coating, covering, or incorporating the
particles or fibres of gun cotton with sugar, that is to say, with either
cane, beet, maple, or other sugars, either raw or refined, or mixtures
of the same, but I prefer to use for the purpose refined or crystallized
sugar. For this purpose I dissolve the sugar in water by means of
heat, or it may be dissolved without heat. I then add the gun cotton
required to be treated, and keep it in the solution of sugar for about
twelve hours, more or less, and afterwards dry it.
In preparing gun cotton for use in guns and for other similar uses in
which the combustion of gun cotton is required to be retarded, I employ
for the purpose sugar in the proportion of about from twenty to ninety per
cent. by weight of the gun cotton, and for blasting purposes I employ
sugar in the proportion of about from ten to fifty per cent. by weight
of the same; but these proportions may be varied if required for other
uses. The requisite drying of the gun cotton after its immersion in
the solution of sugar may be effected either by means of a centrifugal
machine driven at a low speed, or by drying or perforated trays, or by
compression, or by heat. In the latter case the heat may be applied
by means of steam, or hot water, or heated air, at a temperature of
about from one hundred and fifty to two hundred and fifty degrees
(Fanrenheit).
The effect produced on the gun cotton by mixing or combining sugar
therewith is to reduce and regulate the explosive character or quality
of the gun cotton in a degree proportioned to the quantity of sugar
employed for the purpose. And in order to aid the development of
the explosive force as may be required I use a flux or an explosive,
such as white or ordinary gunpowder, or nitrate of soda, or nitrate of

page_text: potash, or ordinary gun cotton, or a gun cotton containing from five
to twenty per cent. of nitrate of potash or nitrate of soda combined
with equal or double the same weight of sugar as before described. The
said flux or fluxes (except ordinary gun cotton) may be added to the
prepared gun cotton, either when in a dried state after its treatment
with sugar in the manner herein-before described, or they may be
added with the sugar in the solution in which the ordinary gun cotton
required to be treated and prepared is immersed. And as the effect
of sugar upon gun cotton or pyroxylin is to harden it, and so make it
more difficult to manipulate, I reduce the bulk by cutting, grinding,
or otherwise, into small pieces, the exact size depending upon the use
they have to be put to, so that I cut into pieces from powder up to
the size of large discs or other forms or shapes most convenient. The
cutting or grinding may be considerably facilitated for some purposes
by cutting the gun cotton small before treating it with sugar. For
small arms the pieces are small, and for large guns and for blasting the
pieces are larger.
Having thus described the nature of the said Invention, and the
means by which the same is to be carried into effect, I hereby declare
that what I claim as of my Invention is, the treatment and preparation
of gun cotton with sugar in the manner and for the purpose or purposes
described.
In witness whereof, I, the said Robert Punshon, have hereunto
set my hand and seal, the Twenty-fourth day of April, in the
year of our Lord One thousand eight hundred and seventy-
one.
Witness,
ROBERT PUNSHON. (L.S.)
WILLIAM VALENTINE DODSWORTH,
17, Collingwood St., Newcastle-on-Tyne,
Stationer.