IMPROVEMENTS IN EXPLOSIVES AND IN CARTRIDGE CASES FOR HOLDING SAME, AND IN DETONATORS FOR USE THEREWITH
Year: 1880

page_text: LETTERS PATENT to Robert Punshon, of Brighton, in the County of Sussex,
Civil Engineer, for an Invention of "IMPROVEMENTS IN EXPLOSIVES AND
IN CARTRIDGE CASES FOR HOLDING SAME, AND IN DETONATORS FOR USE
THEREWITH."
PROVISIONAL SPECIFICATION left by the said Robert Punshon at the
Office of the Commissioners of Patents on the 1st June 1880.
ROBERT PUNSHON, of Brighton, in the County of Sussex, Civil Engineer.
IMPROVEMENTS IN EXPLOSIVES, AND IN CARTRIDGE CASES FOR HOLDING SAME,
AND IN DETONATORS FOR USE THEREWITH."
My Invention consists in the production of an explosive consisting of asbestos or
other suitable porous substance, nitric acid of the specific gravity of 15, and
pieric acid, which can be used with safety for blasting and other purposes to which
explosives can be applied. This explosive can also be stored with safety in large
quantities ready for use or for transport.
In carrying out my Invention I mix the nitric acid with asbestos or with some
other porous substance which, whilst absorbing the nitric acid, will not be affected
by the acid. I then mix in the picric acid with the mixture of asbestos and nitric
acid, whereby a pasty substance is formed that can be pressed hard into cases of
any size suitable for mining or blasting purposes, and for carringe in packages of
wood or paper.
In some cases the picric acid may be dissolved in absolute alcohol
before being mixed with asbestos or its equivalent and nitric acid.
My improved cartridge cases are made of strong brown paper or other paper
coated or covered with a cement made from ground glass and a concentrated
solution of silicate of soda, whereby the action of the nitric acid upon the paper is
prevented; the same cement may be used for making the cylindrical cases for
holding the charges of the explosive. The paper may be also waterproofed upon
the other side, so that the blasting charges may be used in water or in wet holes,
as sometimes met with in mining.
The cartridge cases may also be made of tubes of glass, very thin but strong,
closed at one end, and then covered or cased in strong paper, and the end or ends
closed with asbestos or the paper above described; the end or ends of the tube
may be first closed (after being charged with the explosive) with a soft acid proof
cement.

page_text: In exploding or firing my explosive with an ordinary copper cased detonator, such
as is used with dynamite and other explosive, the copper detonators should be
covered with a conting of the cement made from ground glass and silicate of soda
to prevent any heating of the copper case by the action of the nitric acid upon it,
whereby all danger from a premature explosion of the blasting charge is prevented.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Punshon in the Great Seal Patent Office on the 30th
November 1880.
ROBERT PUNSHON, of Brighton, in the County of Sussex, Civil Engineer.
"IMPROVEMENTS IN EXPLOSIVES, AND IN CARTRIDGE CASES FOR
HOLDING SAME,
AND IN DETONATORS FOR USE THEREWITH."
My Invention consists in the production of an explosive consisting of asbestos or
other suitable porous substance, nitric acid of the specific gravity of 1-5, and picric
acid, which can be used with safety for blasting and other purposes to which
explosives can be applied. This explosive can be stored with safety in large
quantities ready for use or trausport. In carrying out any Invention I mix
the nitric acid with asbestos (finely ground to a powder) or with some other porous
substance which, whilst absorbing the nitric acid, will not be affected by the acid.
I then mix in the pieric acid with the mixture of asbestos and nitric acid, whereby
a pasty substance is formed that can be placed in the cartridge cases. My improved
cartridge cases for holding my explosive are made of strong brown paper coated or
covered with a cement made from ground glass and a concentrated solution of
silicate of soda, whereby the action of the acid upon the paper is prevented.
The paper may also be waterprooofed upon the other side, so that the explosive
may be used in water or in wet holes. The cartridge cases may also be made of
tubes of glass closed at one end, and then covered with paper, and the end or ends
closed with silicate of soda mixed with ground glass, and paper coated as above
described placed over the end or ends (after the tubes have been charged with the
explosive). In exploding or firing my explosive with an ordinary copper made or
cased detonator, such as is used with dynamite, the copper detonators should be
covered or coated with a coating of the cement made from ground glass and silicate
of soda to prevent any heating of the copper case by the action of the nitric acid
upon the copper, whereby all danger from a premature explosion of the blasting
charge is prevented.
Having thus fully described the said Invention, and the manner of performing
the same, I wish it to be understood that what I claim is the absorption of the
nitric acid by asbestos or other suitable porous substance so as to prevent in great
measure the fuming of the acid, and the way described of securing the explosive in
secure acid proof cartridge cases which hold or keep in the fumes of the nitric
acid.
In witness whereof, I, the said Robert Punshon, have hereunto set my hand
and seal, this Thirtieth day of November, in the year of our Lord One
ROBERT PUNSHON. (L.S.)