IMPROVEMENTS IN THE PREPARATION OF SAFETY GUN COTTON
Year: 1871

page_text: LETTERS PATENT to Edward Chambers Nicholson, of Herne Hill;
in the County of Surry, Chemist, and Astley Paston Price, of 47;
Lincoln's Inn Fields, in the County of Middlesex, Chemist, for the
Invention of "IMPROVEMENTS IN THE PREPARATION OF SAFETY GUN
COTTON."
PROVISIONAL SPECIFICATION left by the said Edward Chambers
Nicholson and Astley Paston Price at the Office of the Commis-
sioners of Patents, with their Petition, on the 15th September 1871.
WC, EDWARD CHAMBERS NICHOLSON, of Herne Hill, in the County of
Surrey, Chemist, and ASTLEY PASTON PRICE, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Chemist, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE PREPARATION OF SAFETY GUN
COTTON," to be as follows:-
This Invention relates to the preparation and treatment of gun cotton
in order that the presence of any acid contained in the gun cotton or

page_text: produced or generated by the decomposition of the same, may be
detected, and consists in mixing or incorporating with gun cotton by
preference when in the state of pulp, and also by preference when in a
moistened condition such substances either in solution or in a finely
divided condition as are capable of indicating the presence of an acid
either by the changing of or by the disappearance of their original color.
The soluble coloring substances which we employ are solutions of
litmus or of blue archil, but other soluble tinctorial matters may be
employed the color of which is either changed or destroyed by the action
of an acid.
The insoluble coloring substances which we employ are ultramarine or
lakes or other coloring matters the color of which is capable of being
changed or destroyed by the action of an acid.
In carrying out our Invention we take the gun cotton after it has
undergone the ordinary process of washing, and after any adhering acid
has been removed by that process, or has been neutralized by the
employment of an alkali, and we mix with the same by preference in
the ordinary poaching apparatus with any one or more of the coloring
matters referred to, and we employ the same in such quantity as that the
gun cotton shall assume a clearly visible tint.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Chambers Nicholson and Astley Paston
Price in the Great Seal Patent Office on the 15th March 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, EDWARD
CHAMBERS NICHOLSON, of Herne Hill, in the County of Surrey, Chemist,
and ASTLEY PASTON PRICE, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Chemist, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of September, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty- a
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Edward Chambers Nicholson and Astley
Paston Price, Her special license that we, the said Edward Chambers

page_text: In carrying out our Invention we take the gun cotton after it has
undergone the ordinary process of washing, and after any adhering acid
has been removed by that process or has been neutralized by the employ-
ment of an alkali, and we mix with the same by preference in the
ordinary poaching apparatus after the purification of the gun cotton is 5
completed or in subsequent operations to which the finished product
may be subjected with any one or more of the coloring matters hiercin
referred to, and we employ the same in such quantity as that a clearly
visible tint shall be imparted to the finished gun cotton so that should
any acid be then present or be hereafter formed or generated by decom- 1
position or otherwise, its presence will be indicated by the alteration in
the color or tint of the colored gun cotton.
:
We wish it to be understood that what we have called gun cotton is
intended to comprehend all such substances, compounds, and products
as are known and are comprised under the general designation of nitro- 1
cellulose.
'
What we claim as our Invention is, the coloration, impregnation, or
incorporation of gun cotton or nitro-cellulose either in the course of
manufacture or in the finished condition with tinctorial matters, either
soluble or insoluble, such tinctorial matters being capable of indicating 2
by reason of their change or loss of color the presence or development in
the gun cotton or nitro-cellulose of an acid or of acidulous matters.
In witness whereof, I, the said Astley Paston Price, on behalf of
myself and of the said Edward Chambers Nicholson, have to this
our Specification set my hand and seal, this Thirteenth day of 2
March One thousand eight hundred and seventy-two.