IMPROVEMENTS IN FIRING GUN POWDER FOR BLASTING
Year: 1883

page_text: LETTERS PATENT to Charles William Curtis of the firm of Curtis's and
Harvey of Lombard Street in the City of London Gun-Powder Manufacturers
for an Invention of IMPROVEMENTS IN FIRING GUN POWDER FOR BLASTING
PROVISIONAL SPECIFICATION left by the said Charles William Curtis at
the Office of the Commissioners of Patents on the 2nd June 1883.
CHARLES WILLIAM CURTIS of the firm of Curtis's and Harvey of Lombard Street
in the City of London, Gun-Powder Manufacturers "IMPROVEMENTS IN FIRING
GUN-POWDER FOR BLASTING PURPOSES AND IN APPLIANCES THEREFOR, AND IN
CARTRIDGES
"
The object of this invention is to expedite the ignition and combustion or
explosion of blasting charges or cartridges of black or ordinary gun-powder and
thus to increase its explosive effect so as to approximate it to that of dynamite,
gun-cotton and other explosive chemical compounds. For this purpose I employ
a special igniting appliance containing an explosive such as gun-powder; this
appliance is made as a box or tube or other suitable form and is inserted in the
blasting cartridge or charge. The fuze is connected to it. On igniting this latter
the gun-powder or other explosive in the igniter is ignited and great gas pressure
is created and accumulates therein until the container bursts or some part gives
way which is designed to give way only when such high tension has been obtained.
The rush of high tension gas thereupon penetrates the charge or cartridge with
enormous rapidity not only instantaneously igniting the surface of the grains of
the powder, but also penetrating into their interior, causing their sudden and
complete combustion.
Or the igniter may be made in the form of a rather long tube closed at the fuze
end but open at the other end. In that case the explosion of the igniter finds
vent at the open end but not until an accumulation of pressure has been produced
IP C1

page_text: therein. Such igniters may be used over and over again as they are not destroyed
by the use.
Or the igniter may be of such a form as to combine to a certain extent the effect
or action of the firstly and secondly described constructions.
I may also use the aforesaid igniters in connection with waterproof blasting
cartridges which are made without the usual fuse hole so that they cannot possibly
become useless by the entry of water.
After such a cartridge has been inserted into the bore hole the igniter with the
fuse attached thereto is dropped or placed on the end of it and the hole tamped.
When the igniter is exploded it will shatter the end of the cartridge and the high
tension gas enter it, penetrate it and explode it in all its parts in the manner
already described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles William Curtis in the Great Seal Patent Office on the
1st December 1883.
CHARLES WILLIAM CURTIS of the firm of Curtis's and Harvey of Lombard Street
in the City of London Gunpowder Manufacturers. "IMPROVEMENTS IN FIRING
GUNPOWDER FOR BLASTING PURPOSES AND IN APPLIANCES THEREFOR AND IN
CARTRIDGES
"
The object of this invention is to expedite the ignition and combustion or
explosion of blasting charges or cartridges of black or ordinary gunpowder and
thus to increase its explosive effect so as to approximate it to that of dynamite
gun-cotton and other explosive chemical compounds. For this purpose I employ
a special igniting appliance containing an explosive such as gun powder; this
appliance is made as a box or tube or other suitable form and is inserted in the
blasting cartridge or charge. The fuze is connected to it.
Figure I of the accompanying drawings is a sectional elevation of such a cart-
ridge. A is the cartridge proper consisting of gunpowder contained in a waterproof
or other case of suitable material. B is the igniter exploder or detonator inserted
therein consisting of a brass or other metal cylinder with an inner split tube C
fitted well into it, the annular space E' containing gunpowder. The tube C is for
inserting the fuze. On igniting this latter the gunpowder or other explosive in
the exploder B is ignited and great gas pressure is created and accumulates therein
until the container bursts or some part, that is to say in this case the bottom,
gives way, which is designed to give way only, when such high tension has been
obtained. The rush of high tension gas thereupon penetrates the charge or cart-
ridge A with enormous rapidity, not only instantaneously igniting the surface of
the grains of the powder but also penetrating into their interior, causing their
sudden and complete combustion.
Or the exploder may as shewn in Figure 2 be made in the form of a rather long
tube B closed at the fuze end by a layer D of wadding but open at the other end.
In that case when the cartridge with its exploder has been provided with the fuze,
inserted in the bore hole, and the tamping effected, the explosion of the exploder B
finds vent at the open lower end but not until an accumulation of pressure has
been produced therein.
Or the exploder may be of such an intermediate form as to combine to a certain
extent the effect or action of the firstly and secondly described constructions.
I may also use the aforesaid exploder in connection with waterproof or other
blasting cartridges which are made without the usual fuze hole so that they cannot
possibly become useless by the entry of water and so that no danger can possibly
arise from the powder being exposed or spilt. After my cartridge has been inserted
into the bore hole the exploder with the fuse attached thereto is dropped or placed
on the end of it and the hole tamped. When the exploder is fired it will shatter
the end of the cartridge and the high tension gas will enter it, penetrate it, and
explode it in all its parts in the manner already described.
Figure 3 is a sectional elevation of an exploder suitable for such an application.
It is made cylindrical and has a split tube Ċ inserted through the top for receiving
the fuse.
I prefer to combine the exploder with the charge in one and the same cartridge
as shewn in Figure 4 where the cartridge proper A is tied up in a wrapper E
with the exploder B placed on its end for the sake of convenient transmission and
When the appliance is to be used the end of the wrapper E is untied, the
exploder B taken out, provided with its fuze, and inserted again, and then tied up
use.

page_text: again with the cartridge proper in the outer wrapper E as shewn in Figure 5. It
is then ready to be inserted in the bore hole. This done and the hole being
tamped and the fuze being ignited the fire reaching to the interior of the exploder B
ignites the powder therein and when a sufficiently high tension has been attained
the bottom of the exploder B will yield and the high tension gas enter the powder
in the cartridge A and explode it in all its parts in the manner already
described.
Figure 6 shows another form of cartridge and exploder combined in which the
wrapper case or sack containing the powder is tied tightly some distance from the
top at X and the exploder then placed in its upper part which also is tied at Y
as in Figure 4. When it is to be used the sack is untied at Y and the exploder
provided with its fuse as above described.
I claim.
First The mode of firing blasting charges of gunpowder according to which
the gases evolved from an initial explosion of gunpowder within a strong case
are retained therein until they have attained such a high tension that they
burst the case and with great force penetrate and ignite the "blasting" charge
substantially as and for the purpose set forth.
Second The constructions of the igniter or exploder substantially as described
and shown.
Third: The mode of firing blasting charges of gunpowder according to which
the gases evolved from an initial explosion of gun powder within a strong case
placed upon the closed end of a gun powder cartridge are retained in the case
until they have attained such a high tension that they burst the case break
through the end of the cartridge and with great force penetrate and ignite the
blasting charge substantially as and for the purpose set forth
Fourth: The constructions of combined exploder and cartridge substantially as
described and shewn.
In witness whereof I the said Charles William Curtis have hereunto set my
hand and seal this Thirtieth day of November in the year of our Lord One
thousand eight hundred and eighty three.
IV CURTI
Gal