IMPROVEMENTS IN THE MODE OF AND APPARATUS FOR FIRING EXPLOSIVE COMPOUNDS
Year: 1868

page_text: LETTERS PATENT to Frederick Augustus Abel and Edwin Ormond
Brown, both of the Royal Arsenal, Woolwich, in the County of
Kent, for the Invention of "IMPROVEMENTS IN THE MODE OF AND
APPARATUS FOR FIRING EXPLOSIVE COMPOUNDS."
Sealed the 6th April 1869, and dated the 10th October 1868.
PROVISIONAL SPECIFICATION left by the said Frederick Augustus
Abel and Edwin Ormond Brown at the Office of the Commissioners
of Patents, with their Petition, on the 10th October 1868.
We, FREDERICK AUGUSTUS ABEL and EDWIN ORMOND BROWN, both
of the Royal Arsenal, Woolwich, in the County of Kent, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE MODE
OF AND APPARATUS FOR FIRING EXPLOSIVE COMPOUNDS," to be as follows:-
Our Invention relates to a new mode of exploding gunpowder,
gun cotton, or pyroxiline, gun sawdust, or the compound know as
"Schultze's powder," and other explosive mixtures or compounds.

page_text: It is well known that when gunpowder, gun cotton, gun sawdust, or
the compound known as "Schultze's powder," or explosive compounds,
such as the mixtures of chlorate of potash or nitrate of potash with the
prussiates of potash, with metallic sulphides or sulphur, or with tannin,
resin, or other solid vegetable substances, are ignited in the open air by
means of a highly heated body or flame, they burn without producing
any violent explosion, and that it is necessary in order to develop their
explosive action when thus inflamed to confine them in receptacles such
as shells, or to enclose them in bore holes or blast holes by the well-
known methods of tamping.
Now we have discovered that if any of the aforesaid explosive
substances are subjected to the concussion produced by the explosion in
contiguity or in actual contact with them of even a small quantity of a
powerfully detonating substance, such as the fulminate of mercury, they
explode instantaneously and with violence, even if they are quite freely
exposed to the air, and that they do not therefore require confinément in
strong cases or by tamping in bore holes to develop their explosive and
destructive effects. The way in which we apply this fact to the violent
explosion of gunpowder, gun cotton, gun sawdust, and other explosive
compounds, is as follows:-A small cylinder or tube, closed at one end
and consisting of wood, paper, papier maché, cardboard, or metal, is
charged with a small quantity of fulminate of mercury, say, from ten to
thirty grains, if a metal tube is employed. A loose plug of gun cotton is
inserted over the fulminate, so as to confine the latter in the closed end
of the tube; the open end is then closed with a piece of thin paper,
which may be varnished to exclude moisture. Any other convenient
method of closing the tube may however be used. To employ these
tubes or detonators for exploding gunpowder, gun cotton, or other
explosive substances, a piece of ordinary mining fuze is inserted into the
open end of the tube from which the covering has been removed, and the
tube is firmly attached to the fuze by means of a pair of pliers. The
fuze thus prepared is then either inserted into or placed upon the charge
to be exploded, care being taken that only the detonator is in contact
with the charge.
Electric fuzes may also be applied to explode gunpowder, gun cotton,
and the other explosive substances by detonation; and for this purpose
it is necessary to replace the ordinary priming charge of gunpowder
usually contained in such fuzes by a priming charge of powerfully

page_text: detonating powder, such as the fulminate of mercury, from 10 to 50
grains of the powder being required, according to the construction of the
particular electric fuze.
We are aware that it has been previously proposed to apply a
detonating fuze or to attach a detonating cap to the ordinary mining
fuze for the purpose of exploding nitro-glycerine and the preparations of
that substance which are known as "dynamite," the employment of
such arrangement being necessary in order to develop the explosive
powers of those substances. But the producing a violent explosion of
gunpowder, gun cotton, and other explosive compounds (excepting
nitro-glycerine and "dynamite") when in an unconfined state, or when
enclosed only in weak receptacles by means of a concussion produced by
the explosion of a charge of detonating powder, according to our present
Invention, has never before been effected.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Augustus Abel and Edwin Ormond
Brown in the Great Seal Patent Office on the 10th April 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, FREDERICK
AUGUSTUS ABEL and EDWIN ORMOND BROWN, both of the Royal Arsenal,
Woolwich, in the County of Kent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of October, in the
year of our Lord One thousand eight hundred and sixty-eight, in
the thirty-second year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto us, the said Frederick Augustus Abel
and Edwin Ormond Brown, Her special licence that we, the said
Frederick Augustus Abel and Edwin Ormond Brown, our executors,
administrators, and assigns, or such others as we, the said Frederick
Augustus Abel and Edwin Ormond Brown, our executors, adminis-
trators, and 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
MODE OF AND APPARATUS FOR FIRING EXPLOSIVE COMPOUNDS," upon the con-

page_text: dition (amongst others) that we, the said Frederick Augustus Abel and
Edwin Ormond Brown, our executors or administrators, by an instru-
ment in writing under our or their hands and seals, or under the hand
and seal of one of us or them, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to
be performed, and cause the 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 Frederick Augustus Abel, on behalf
of myself and the said Edwin Ormond Brown, do hereby declare the
nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
Our Invention relates to a new mode of exploding gunpowder, gun
cotton, or pyroxyline, gun sawdust, or the compound known as
"Schultze's powder," and other explosive mixtures or compounds.
It is well known that when gunpowder, gun cotton, gun sawdust,
or the compound known as "Schultze's powder," or explosive com-
pounds, such as the mixtures of chlorate of potash or nitrate of potash
with the picrates of potash or ammonia, the prussiates of potash with
metallic sulphides or sulphur, or with tannin, resin, or other solid
vegetable substances, are ignited in the open air by means of a highly
heated body or flame, they burn without producing any violent ex-
plosion, and that it is necessary in order to develop their explosive action
when thus inflamed to confine them in receptacles such as shells, or to
enclose them in bore holes or blast holes by the well-known methods of
tamping.
Now we have discovered that if any of the aforesaid explosive
substances are subjected to the concussion produced by the explosion in
contiguity to or in actual contact with them of even a small quantity of
a powerfully detonating substance, such as the fulminate of mercury,
they explode instantaneously and with violence, even if they are quite
freely exposed to the air, and do not therefore require confinement in
strong cases or by tamping in bore holes to develop their explosive and
destructive effects. The way in which we apply this fact to the violent
explosion of gunpowder, gun cotton, gun sawdust, and other explosive
compounds, is as follows:-A small cylinder or tube, closed at one end
and consisting of metal, wood, paper, papier maché, cardboard, or a com-

page_text: bination of these, is charged with a small quantity of fulminate of
mercury, say, from ten to thirty grains, if a metal tube is employed. A
loose plug of gun cotton is inserted over the fulminate so as to confine
the latter in the closed end of the tube. The open end is then closed
with a piece of thin paper, which may be varnished to exclude moisture.
Any other convenient method of closing the tube may however be used.
To employ these tubes or detonators for exploding gunpowder, gun
cotton, or other explosive substances, a piece of ordinary mining fuze is
inserted into the open end of the tube from which the covering has been
removed, and the tube is firmly attached to the fuze by nipping the
latter upon the former by means of a pair of pliers, or by securing it in
any other convenient manner. The fuze thus prepared is then either
inserted into or placed upon the charge to be exploded, care being taken
that only the detonator is in contact with the charge.
Electric fuzes may also be applied to explode gunpowder, gun cotton,
and the other explosive substances by detonation; and for this purpose
it is necessary to replace the ordinary priming charge of gunpowder
usually contained in such fuzes by a priming charge of powerfully
detonating powder, such as the fulminate of mercury, from 10 to 50
grains of the powder being required according to the construction of the
particular electric fuze employed, the particular detonating powder used,
and according to the particular explosive agent to be fired by the said
fuze.
The said violent explosion of the gunpowder, gun cotton, or other
explosive compounds may be effected as before stated either when these
materials are quite unconfined or when only partially confined, as in
blast holes, or open receptacles, or when enclosed in weak receptacles,
such as thin cases of wood or sheet metal, waterproof or other bags or
vessels of glass, earthenware, or other materials, which receptacles or
vessels may simply be placed against or upon the object to be acted upon
by the explosion.
We are aware that it has been previously proposed to apply a
detonating fuze or to attach a detonating cap to the ordinary mining
fuze for the purpose of exploding nitro-glycerine, and the preparations of
that substance, which are known as "dynamite," the employment of
such arrangement being necessary in order to develop the explosive
powers of those substances. But what we claim is,-
First. Producing a violent explosion of gunpowder, gun cotton, and

page_text: other explosive compounds (excepting nitro-glycerine and "dynamite")
when in an unconfined state or when enclosed only in weak receptacles,
by means of a concussion produced by the explosion of a charge of
detonating powder.
Second. The employment for producing such violent explosions of a
fuze or detonating primer constructed for adaptation to the ordinary
mining fuze, and charged with a detonating powder, substantially as
herein-before described.
Third. The combination of a charge of detonating powder with an
electric fuze for producing the violent explosions, as aforesaid.
In witness whereof, I, the said Frederick Augustus Abel, have
hereunto set my hand and seal, this Ninth day of April, in the
year of our Lord One thousand eight hundred and sixty-nine.