provements in Blasting and Blasting Cartridges.
Year: 1899

page_text: PROVISIONAL SPECIFICATION
Improvements in Blasting and Blasting Cartridges.
I, JAMES MACNAB, of G, Red Lion Square, in the County of Middlesex, Engineer,
do hereby declare the nature of this invention to be as follows:-
--
This invention relates to improvements in blasting and blasting cartridges and
in new combinations and modifications of the same for use in coal mines and
other underground workings as well as on the surface, and refers more especially
to further improvements and combinations in my safety cartridge inventions No.
9688 of 1893 and No. 16777 of 1897, together with more efficient modifications
and applications contained therein, whereby the cartridges are made doubly safe
and trebly so in some cases, combined with a more simple and convenient method
of manufacturing and employing them in practice, by which greater reliability
of action is secured and efficiency also obtained, in conjunction with less risk of
igniting the firedamp and coal dust of the mine. For example, and in illustration
the modification described in my Patent No. 9688 of 1893, where I employ
ammonium nitrate or other flame-cooling ammonium salts or cooling substances,
in a crushed or granulated form sealed in a waterproof tube or case, is made
more safe and efficient.
the same.
In practice I employed two or more of these tubes or cases, containing the above
ammonium salts, or their flame-cooling equivalents, carefully cemented from the
atmosphere and kept separate from the gunpowder or explosive but embedded in
I usually placed one tube or case of salts embedded in the meal or fine-
grain quick-burning gunpowder near the bottom of the case to cool-down the flame
at this part to prevent ignition of gas should it search back at the far-end of the
borehole. I invariably keep the case of cooling salts separate from the gunpowder
to admit of free combustion of the powder, and place the other case or tube of
cooling salts at the other end or outer extremity of the case, at or near the
opening or mouth of the cartridge case adjoining the meal or fine-grain quick-
burning gunpowder.
The igniting fuse or electric wires were tied externally alongside the tube or
case of cooling salts at two points of the case to secure the fuse or wires from
slipping or being drawn off the case of salts which was then placed upon the
top of the gunpowder and tied carefully in ready for placing in the borehole.
These cartridges always contained the tubes or cases of cooling salts in their
interior ready for use and for inserting the firing fuse.
Now, in practice this method left a lateral air-space alongside the part where
the fuse was tied to the case or pellet of cooling salts which had to be filled up
with some of the interior gunpowder charge-this manipulation of the cartridge
was inconvenient and caused some delay before it could be placed in the bore-
hole and fired in the usual manner.

page_text: The improvement I invented to overcome this objection was to provide the
tube or case of cooling salts with an interior central or side hole in the form of a
paper tube or case to admit the Bickford or electric fuse to pass down into the
interior of the meal or fine-grain gunpowder in the cartridge ready for at once
inserting in the borehole, thus avoiding any delay whatever.
Another useful and two-fold advantage was secured by this means, for it
admitted of the tube or case of cooling salts to be made the full diameter of the
cartridge case proper which now really plugs the mouth of the cartridge case con-
taining the explosive charge and prevents any flame from darting out of the hole
and past the cooling tube without being damped down or cooled before it can
reach the workings.
This improvement is fully described in my Specification No. 16777 of 1897, in
combination with a cap-cover or disc of metal containing a hole for the fuse and
may be now retained with advantage.
I also describe it for additional safety as a tamping pellet-case of flame-cooling
salts for placing upon the external top of the gunpowder cartridge and tied
securely there, in which position the space round the neck is always freely pierced
to admit of direct connection between the gunpowder and the flame-cooling salts
contained in the pellet-case or tube, thus a two-fold advantage is secured and will
further contribute to ensure safety in coalmine workings.
For extra or treble safety this pellet-case may be, if desired, further assisted by
placing two or more small cases of flame-cooling salts or other cooling substances
upon the top or front of the safety pellet-case which the rammer or tamping bar
will crush in the hole, while a pellet of damp plastic clay will keep it in position
till the usual hard stemming has been completed, or in lieu of the cooling salts
being in cases they may be intermixed or kneaded together with. the damp plastic
clav.
A still further improvement is to make this pellet case or tube of salts in the
form of small tubes of waterproof-paper or vegetable parchment or other suitable
material, and to charge them with flame-cooling salts of the same kind cemented
or sealed in and tied in a group or bundle ready for inserting in the borehole,
after which they are placed in the pellet case, or the bundle of tubes may be
placed in the cartridge, without a case, and tied in ready for use. The bundle
contains by preference seven tubes with one in the centre or at the side to be
hollow for inserting the firing fuse, and when placed in a pellet-case the bottom
of the case is closed by a disc of combustible paper or other inflammable material;
the tubes of salts may be also composed of similar paper to enable the explosive
flame to be readily cooled down by the small diameter tubes, which now present
a much larger exposed bearing surface for cooling the flame than as described
in my invention No. 16777 of 1897-the action of which is practically instan-
taneous and more reliable.
In lieu of dry powdered or granulated flame-cooling salts these tubes may
contain the ammonium or other salts in the form of a thin or a suitably thick
solution especially about the consistency of rubber solution, to prevent it from
running, sealed or cemented in suitable tubes or vessels of waterproof material
if made of glass they are sealed by the blow-pipe, and may be afterwards dipped,
especially the neck part, in a combustible solution like shellac or gutta-percha, or
rolled in gutta-percha tissue, or paper, to prevent liability of fracture in transit,
but being of a small diameter perfect immunity from this has been proved by
long experience. Further, two or more of the cooling salts or agents may be
advantageously mixed together to prevent caking in transit or in storage in the
form of one being finely crushed or powdered and the other finely granulated, for
example, ammonium or sodium bi-carbonate, including ammonium sulphate or
carbonate, may be crushed or powdered and usefully mixed with finely granu-
lated neutral ammonium oxalate, or vice versa, which will assist the explosive
fame to more quickly and freely secure decomposition of the cooler, similar to
mixing meal or fine-grain and large grain gunpowder together to accelerate their

page_text: quick-burning action for safety blasting-as described in my Patent of 1893. This
latter treatment of the salts in solution or dry, also applies to their use with
guncotton, and the like, in a meal or fine-grain, or granulated state. In using
large or coarse grains of gunpowder (or other explosives) in this manner, but the
size of fine or large grains must be strictly made to rapidly burn within the
limit of safety or area of quickburning-first practically applied by me for pre-
venting ignition of fire damp and coaldust in coalmines-described in my Patent
of 1893 an important advantage is gained by slightly retarding combustion thus,
especially for certain descriptions of rending work, with granulated cellulose
explosives of nitrated sawdust (wood dust), like Schultze's gunpowder finely granu-
lated, in combination with a proportionate quantity of the same crushed, or it
may be used separately including nitrated wood-wool, or other suitable cellulose
substance.
To further secure better rending or useful spreading action in the quick-
burning meal or granulated guncotton, when fired by simple fuse ignition or by
an electric fuse, without a detonator cap, (described in my Patent of 1897) I
employ in combination with the same a proportionate charge of finely powdered
or finely granulated charcoal or other carbon or similar-acting substance, which
is intermixed with the finished meal or granulated explosive to obtain more gas
and to slightly retard combustion, for coal or other similar tender work, to thus
regulate the quick burning speed of the same and imitate the action of gun-
powder. To further assist combustion of the charcoal or carbon and the gun-
cotton I add a small charge of finely crushed chlorate of potash or sali petre
securely sealed in a delicate tube of copper or paper, or other suitable material,
and kept separate from the explosive combination. To cool-down the flame and
absorb the fumes, I also add a suitable charge of liquid ammonia or cooling salts
in solution or in a crushed or granulated form embedded in the explosive-not
mixed--and with or without the safety tamping pellet-case of salts or solutions,
or the cooling case is placed on or in the charge in the interior of the case, but
not mixed.
To further utilize this useful method of adding or combining a proportionate
charge of charcoal or other carbon and intermixing it with guncotton when in a
meal or crushed state for the purpose of regulating its rapid-burning speed or
action for certain kinds of strong or stubborn work, I also. compress the same
This com
into pellets containing a deep central hole to receive a detonator cap.
pressed carbonized pellet may be employed for safety in conjunction with a meal
or fine grain cartridge of guncotton in which case the compressed pellet, con-
taining a detonator cap safely fixed in the holder is first placed at the bottom of
the borehole, then followed by a carbonized cartridge of meal or fine grain
guncotton, as described, with the firing fuse inserted and tied in the case, and
with or without a flame-cooling agent for certain descriptions of safety work in
coal mining and elsewhere underground. The combination charge, is then firmly
tamped in the borehole and fired, when the cartridge on the top will self-ignite
the detonator cap, in this novel manner, and explode the compound pellet with-
out any danger whatever. This method of combining finely crushed or finely
granulated charcoal, carbon, or other similar-acting combustible substance, may
be with advantage combined and intermixed with finished dynamite or mixed
during the unfinished stage, or with other nitroglycerine compounds or suitable
quickburning high explosive, to reduce their too violent action and rapid-burning
speed for obtaining more efficient rending work.
When one or more compressed carbonized pellets or compound charges of gun-
cotton are placed in the borehole for heavy work combined with a cartridge of
the meal or granulated guncotton, carbonized or uncarbonized, already described,
and with or without the flame-cooler, the detonator cap requires no manipulation
or fixing on the igniting fuse and is, therefore, absolutely safe and free from
the usual danger, combined with reliability of ignition.
This safe method is also applicable for use with other detonating explosives.

page_text: This combination and safe method of firing the detonator cap, can also be fired
by the quick-burning gunpowder safety cartridge, which can De employed in
lieu of the guncotton one.
Further, this flame-cooling cartridge of quickburning meal or fine grain gun-
powder may be combined with my safety tamping pellet-case, (described in my
Patents of 1893 and 1897). It can be improved and additional safety obtained
by reducing, the temperature of the finished gunpowder through largely increas-
ing the proportions or equivalents of charcoal or carbon, to the saltpetre and
sulphur, for obtaining a greater volume of gas (described in Spon's Engineer-
ing) I also combine with the ingredients of same, a small proportionate charge
of crushed chlorate of potash, (or a charge of saltpetre instead of the same) say
about to an ounce to every 4 ounces of powder-securely sealed or cemented
in tubes or caps of copper, paper, or other material, to keep it separate from the
finished gunpowder, but in touch with it (described in my latent of 1893),
and which will impart extra strength to the explosive and also assist with its
oxygen the more perfect combustion of the charcoal or carbon, intermixed therein,
and with which is combined a flame-cooling agent and fume or heat absorber, of
either liquid ammonia or ammonium salis, finely crushed or finely granulated,
or in a solution form of a thin or suitably thick consistency which will also
neutralize the fumes of carbonic oxide. However, for certain descriptions of
blasting, the flame-cooler may be dispensed with, if desired. The equivalents of
charcoal or other carbon, I prefer to employ is about five to six and not more
than six and a half, when combined with the usual proportions of saltpetre and
sulphur intermixed, or say one equivalent of saltpetre and one equivalent of sul-
phur, to disengage from 12 to 14 volumes of gas, instead of the usual 8 volumes.
Another useful and suitable proportion of ingredients for quickburning powder
for safety mining, consists of in every 100 parts by weight of the finished
gunpowder of not more than 84 parts and not less than 81 parts of saltpetre, and
not more than 22 parts and not less than 19 parts of charcoal or carbon, and with
one half part and not less than one quarter part of pure sulphur-the whole to be
well intermixed or incorporated, and with the addition to the finished powder of
about one quarter to half an ounce of chlorate of potash, or other oxygen-giving
substance, to every four ounces of powder, in a combined form, but not inter-
mixed, and kept separate in a sealed case or tube. This gunpowder propor-
tions may be safely employed, (when desired without the cooler) in a meal or fine
grain quickburning form, but the size of grain must be kept within the limits of
safety, for coal mining blasting, as described in my Patent of 1893, although for
very dangerous work this combination gunpowder cartridge when required, may
be advantageously combined for extra safety, with a flame-cooling and fume-
absorbing agent embedded in the charge, but not intermixed or a safety tamping
pellet-case of the same may be employed instead, or both used in conjunction
for absolute safety. With the object of safety and securing more simultaneous
and uniform decomposition of the cooling agents enclosed in tubes or cases and
containing either liquid ammonia, or suitable cooling salts, like ammonium
nitrates, oxalates, carbonates, sulphates, bi-carbonates, sodium carbonates, and
the like, (as described in my Patent of 1893) in the form of either a suitably thin
or thick solution, or in a dry and crushed or finely granulated state, and
employed either separately or combined, this method also applies to sealed tubes
or cases of chlorate of potash or saltpetre, when combined with the meal or finely
granulated explosives when in conjunction and embedded in the charge, for also
obtaining simultaneous decomposition or combustion, which is simply and reliably
obtained by employing a length of delicate copper wire which encircles the tubes
or cases and holds them with a twist of the same at the desired points of the
explosive charge in which they are embedded. For example, they are fixed on
the wire at given intervals, say one cooler-tube at the end or bottom of the
cartridge case, with one in front, next to the neck or opening, and with a tube
or case of chlorate of potash or saltpetre between or at the middle of the charge,

page_text: the copper wire of fixed tubes or cases is then placed in the cartridge case, and
the meal or granulated explosive charge is run in, and surrounds the tubes the
outer end of the copper wire is then tied in at the neck of the cartridge case
ready for use. By this improved method the tubes or cases are prevented
from shitting, while one cooler rigidly kept in front of the explosive Hame the
other retains its position at the far-end of the charge, to prevent the flame from
searching back, without being cooled-down-the incandescent. flame being thus
cooled between two dampers, while the small charge of chlorate of potash or salt
petre secures additional strength and more complete combustion of the explosive...
The safety cap-cover, containing a fuse hole, and disc of tinned metal, can
be placed at the bottom and on the top of the explosive charge, (as described
in my Invention of 1897), and may be thus advantageously employed and effi-.
ciently contribute to obtain extra safety, as proved in my former practice. The
safety metallic device for preventing blown-out shots (described in my Patent of
1893), containing a hole for the fuse, is considerably and usefully improved by
simply using two light flat discs of tinned metal, both connected by a delicate
rod of the same metal by being screwed or riveited at each end of the said rod,.
but instead of employing the device entirely in the interior of the cartridge case,
it is now more conveniently used on the exterior of the case, or charge, when the
bare point or fuse hole end of the connecting rod without the cap-dise, is forced.
up through the bottom of the case and the disc firmly cemented there. The case.
is then filled up with the combined charge, and with or without the cooling
tubes or cases tied on the rod to hold them in position, similar to the copper wire.
method, already described, the cap-cover is then screwed down and rivetted, the
fuse hole is now closed with a piece of damp-proof paper or calico and cemented
down, after which the case with its contents is securely tied in at the neck ready,
for use. When this armour-clad case is employed the metallic cap-cover and disc
already referred to, is dispensed with, as the metallic device is used instead of
the same, although the cap-cover, with its turned up edge, may be efficiently
applied, especially upon the top of the pellet of plastic clay.
Lastly, when tubes or cases of ammonium salts are employed as cooling agents,
especially ammonium nitrate, but owing to its many modes of decomposition (7-
as proved by Bertholet), it is consequently irregular and dangerous in its action,
it is of importance to keep the diameter of the tubes or cases very small, to coun-
teract this, as practised by me and preferred, to ensure instantaneous action and
decomposition whether in solution or in a finely granulated or crushed state-
this rule applies to other ammonium salts and cooling substances, but generally,
these smaller diameter tubes or cases are more uniformly efficient and reliable in
their action when employed in this form, but numerous in number, rather than
in larger charges and less numerous, but for uniform safety they must be kept
entirely separate from the explosive charge and not intermixed, for retardation in.
combustion and decomposition is at once set-up if mixed, which is a fundimental
error in making a true safety cartridge for preventing the ignition of firedamp
and coaldust in coalmines, even a detonator cap, which is employed to overcome
this defect, can never be absolutely depended upon in practice.
Datad this 0th day of Wohrmony 1900'

page_text: the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
My invention relates to improvements in blasting and in blasting cartridges for
use in coal mines and other underground workings as well as on the surface,
and refers more especially to further improvements in my safety cartridge inven-
tions No. 9688 of 1893, and No. 16777 of 1897, whereby the cartridges are made
doubly safe and trebly so in some cases, and a more simple and convenient method
of manufacturing and employing them in practice is obtained by which greater
reliability of action is secured and efficiency also obtained, in conjunction with
less risk of igniting the fire damp and coal dust of the mine.
For example the modification described in my Patent No. 9688 of 1893 where
I employ ammonium nitrate or other flame cooling ammonium salts or cooling
substances in a crushed or granulated form sealed in a waterproof tube or case is
made more safe and efficient by the improvements forming the subject of this
invention. In this arrangement I employed two or more of these tubes or cases
containing the above ammonium salts, or their flame-cooling equivalents, care-
fully cemented from the atmosphere and kept separate from the gunpowder or
explosive but embedded in the same. I usually placed one tube or case of salts
embedded in the meal or fine-grain quick burning gunpowder near the bottom
of the case to cool down the flame at this part to prevent ignition of gas should
it search back at the far end of the borehole. The case of cooling salts was kept
separate from the quick burning gunpowder to admit of free combustion of the
powder: The other case or tube of cooling salts was placed at the other end or
outer extremity of the case at or near the opening or mouth of the cartridge case
adjoining the meal or fine-grain quick burning gunpowder. The igniting fuse
or electric wires was or were tied externally alongside the inner tube or case of
cooling salts at two points of the case to secure it or them from slipping or
being drawn off the case of salts, which was then placed upon the top of the
gunpowder and tied carefully in the cartridge case ready for placing in the bore
hole. These cartridges always contained the tubes or cases of cooling salts in
their interior ready for use and for inserting the firing fuse. Now, in practice
this method left a lateral air space alongside the part where the fuse was tied to
the case or pellet tube of cooling salts which had to be filled up with some of
the internal gunpowder charge and this manipulation of the cartridge was
inconvenient and caused some delay before it could be placed in the borehole and
fired in the usual manner. The improvement I invented to overcome this
objection was to provide the tube or case of cooling salts with an interior central
or side hole in the form of a paper tube or hollow case to permit the Bickford
or electric fuse to pass down into the interior of the meal or fine-grain' gunpowder
in the cartridge ready for at once inserting in the bore hole, thus avoiding any
delay whatever. Another useful advantage was secured by this means, for it
admitted of the tube or case of cooling salts being made the full internal diameter
of the cartridge case proper, which now really plugged the mouth of the cartridge
case containing the explosive charge and prevented any flame from darting out of
the hole and past the cooling tube contents without being damped down and
cooled before it could reach the workings. This improvement is fully described
in my Specification No. 16777 of 1897, in combination with a cap, cover or disc of
metal containing a passage for the fuse. For additional safety the tamping
pellet case of flame cooling salts can be placed upon the outer top or front of the
gunpowder cartridge case and tied securely there, in which position the space a
round the neck is always freely pierced to admit of direct connection between the
gunpowder and the flame cooling salts contained in the pellet case or tube, so
that a two-fold advantage is secured which further contributes to safety in coal
mine workings. As a still further safeguard I may, if desired, place two or
more small cases of flame-cooling salts or other cooling substances upon the
top or front of the safety pellet-case which the rammer or tamping bar will
crush in the hole while a pellet of damp plastic clay will keep it in position

page_text: till the usual hard stemming has been completed; or instead of using the cooling
salts in cases I may intermix or knead them together with the danip plastic
clay.
a
M'
A still further improvement is to make this pellet-case of salts in the form of
small tubes of waterproof paper, by preference of nitrated cellulose paper,
vegetable parchment, or the like and to charge them with flame-cooling salts
of the same kind, cemented or sealed in, the said tubes being tied in a group or
bundle ready for inserting in the borehole, after which they are placed in the
pellet-case; or the bundle of tubes may be placed in the cartridge, without a
case, and tied in ready for use. The bundle contains, by preference seven tubes
with one in the centre, or at the side, which is hollow or empty for the insertion
of the firing fuse, and when placed in a pellet-case the bottom of the case is
closed by a dise of combustible nitrated cellulose paper, or other inflammable
material. The tubes of. salts may be also composed of similar combustible paper
to enable the explosive flame to be readily cooled down by the small diameter
tubes, which now present a much larger exposed bearing surface for cooling the
flame than with the arrangements as described in the Specification of my Patent
No. 16777 of 1897. To ensure that the cooling action shall be practically
instantaneous and thoroughly reliable the cooling tubes should not be more than
about 2 to 3 inches in length:
In lieu of dry powdered or granulated cooling salts in a loose state the tubes
may contain the ammonium or other salts in the form of a pasty solution about
the consistency of rubber solution or of jelly, to prevent running; for this purpose
the salts may be combined with thin liquid gutta-percha, or shellac varnish,
rosin, starch, molasses or liquid sugar or other suitable solution, well dried by
heat; this method of preparation also assists in preventing the absorption of
water vapour present in the atmosphere...
If the tubes are made of glass they are sealed by the blow-pipe, and may be
afterwards dipped, especially the neck part, in a combustible solution of shellac
varnish, gutta-percha, or nitrated cellulose or they may be rolled in gutta-
percha tissue or paper to prevent any liability of fracture in transit, which is,
however, not likely to happen owing to the small diameter of the tubes; in the
case where the tubes contain liquid ammonia the latter may be thickened with
meal guncotton.
Furthermore, two or more of the cooling salts or agents may be advantageously
mixed together to prevent caking in transit or in storage, one of the agents being
finely crushed or powdered and the other being finely granulated; for example,
ammonium or sodium bi-carbonate, ammonium sulphate or carbonate or
ammonium perchlorate, may be crushed or powdered and usefully mixed with
finely granulated neutral ammonium oxalate, or other suitable salt, or vice versa.
This mixture assists the rapid decomposition of the cooler, as is the case with a
mixture of meal or fine grain and large grain gunpowder as described in the
Specification of my Patent No. 9688 of 1893.
This treatment of the salts in solution or dry also applies to their use with
guncotton and the like, in a meal or fine-grain or granulated state. In using
large or coarse grains of gunpowder (or other explosive) in this manner, the size
of fine or large grains must be carefully chosen such that the explosive rapidly
burns within the limits of safety. An important advantage is gained by slightly
retarding combustion thus, especially for certain descriptions of rending work
with granulated cellulose explosives of nitrated saw dust (wood dust) such as
Schulzes' gunpowder finely granulated, in combination with a proportionate
quantity of the same crushed, or separately; nitrated wood wool; or other suitable
cellulose substance. To further secure better rending or useful spreading action
in the quick burning meal or granulated guncotton when fired by- simple fuse
ignition or by an electric fuse, without a detonator can I employ in combination
with the same a proportionate charge of finely powdered or finely granulated
charcoal or other suitable carbon or similarly acting substance, which is inter-
0

page_text: mixed with the dry finished meal or granulated explosive, to obtain more gas and
to slightly retard combustion for coal or other similar tender blasting, whereby
too quick-burning is regulated or retarded and the action of gunpowder imitated.
To further assist the combustion of the charcoal or other carbon and the gun-
cotton I add a small charge of finely crushed chlorate or perchlorate of potash,
or saltpetre securely sealed in a delicate tube of copper or nitrated paper or other
suitable material and kept separate from the explosive combination, or when
desired. the chlorates may be mixed with the carbonized or uncarbonized gun-
cotton meal in fine grains or compressed.. To cool down the flame and absorb the
fumes, I also add a suitable charge of liquid ammonia or cooling salts, in solution
or in a crushed or granulated form, embedded in the explosive but not mixed
therewith and with or without the safety tamping pellet-case of salts or solu-
tions; or the cooling case is placed on or in the explosive charge in the interior
of the case but not mixed therewith. A suitable charge of ammonium nitrate or
other cooler would be about 12 to 25 per cent. by weight combined with the
finished explosive but varied more or less according to the cooler used and the
work to be done. I sometimes add a proportionate charge of charcoal or other
suitable carbon, say about 12 to 25 per cent. by weight to the finished gun-
cotton and mix it therewith; these proportions may, however, be suitably
varied for certain kinds of strong or stubborn work. I also compress the same
into pellets containing a deep central hole to receive a detonator cap. This
compressed carbonized guncotton pellet may be employed for safety in con-
junction with a meal or fine grain cartridge of guncotton in which case the
compressed guncotton pellet, containing a detonator cap securely and safely fixed
in the holder, is first placed at the bottom of the borehole, then followed by a
carbonized cartridge of meal or fine grain guncotton, as described, with the
firing fuse inserted and tied in the case; with or without a flame-cooling agent,
for certain descriptions of safety work in coal mining and elsewhere underground.
To facilitate instant decomposition and obtain a larger exposed flame bearing
surface, a tubular straw or a hollow combustible tube of nitrated cellulose paper
may be inserted in the centre of the tubes or cases of cooling salts and
securely closed in. Further, as a substitute for the copper wire method of keeping
the separated tubes in position in the case, a tube of nitrated paper, containing
the cooler, may be made the full length of the cartridge case and choked at
intervals, and in the last, or bottom, division of this I place the chlorate or
perchlorate while the metal discs at both ends will keep it central when tied in
at the neck of the case.
The following is a suitable method of charging the cartridge case and com-
pressing the finely powdered meal guncotton--whether carbonized or uncarbonized
for the efficient blasting of various descriptions of work and for obtaining
the necessary density for effectively rending such work, that is to say, the cases
or tubes of cooling salts and chlorates or perchlorates are lowered into position
in the cartridge, a metallic disc being first placed in the interior end-this
device being specially adapted for colliery blasting, the dry powdered gun-
cotton is then run in and surrounds the above cases or tubes of cooling sub-
stances which are kept central; the guncotton is then well shaken down when
required for light blasting work, and a disc-cover, with a fuse hole, placed upon
the top of the explosive charge and all tied in ready for use.
When a cartridge is required for heavier work the guncotton meal is firmly
pressed down by hand with a wooden rammer in instalments until the charging
is completed to thus concentrate the carbonized and chlorated guncotton meal.
To obtain greater density a suitable hand lever press and piston is employed.
Should a pellet form of cartridge be required, similar to a gunpowder pellet or
block with a central hole, it is compressed in a damp state in a copper holder
of the size and diameter of those pellets; the holder having a central spike
slightly tapered to form the hollow core for inserting the fuse and also for
encircling the tubes of cooling salts and chlorates,

page_text: The medium density of this pellet will still keep the guncotton flexible in the
case in which it is compressed, to admit of its being fire by simple ignition-
without a detonator-by a cartridge of powdered or meal guncotton. To further
increase the density it must be treated when wet and compressed in the usual
well-known manner and thoroughly dried in this form, so that when placed at
the far end of the borehole it may be ignited by a meal guncotton cartridge,
as described, which will decompose it without a detonator cap, although for extra
strong blasting work, a detonator may be employed.
When one or more compressed carbonized pellets or compound charges of
guncotton is or are placed in the borehole for heavy work in combination with.
a cartridge of the meal or finely granulated guncotton, carbonized or uncarbonized
already described--and with or without the flame cooler, the detonator cap requires
no manipulation or fixing on the igniting fuse and is, therefore, when thus
placed absolutely safe and free from the usual danger. This safe detonator
method is also applicable for use with other detonating explosives when similarly
placed. In combination therewith I can also use the quick burning gunpowder
safety cartridge, which can be employed in lieu of the meal guncotton one for
which a compressed gunpowder pellet may be substituted. Furthermore, the
flame-cooling cartridge of quick burning meal or fine grain gunpowder may
be combined with my safety tamping pellet-case-described in the Specification
of my Patents No. 9688 of 1893 and No. 16777 of 1897. Additional safety
can be obtained by reducing the temperature of the finished gunpowder by largely
increasing the proportions of charcoal or the like, to the saltpetre and sulphur.
I can also combine therewith a small proportionate charge of crushed or
powdered chlorate or perchlorate of potash (or a further charge of saltpetre)
say about to an ounce to every 4 ounces of finished gunpowder or guncotton-
securely sealed or cemented in tubes or caps of copper, paper, or other suitable
material, to keep it separate from the finished gunpowder or guncotton, but in
touch with it and which will impart extra strength to the explosive and also
assist with its oxygen the more perfect combustion of the charcoal or carbon
mixed therewith. In this case the flame cooler may or may not be employed
according to requirements.
The equivalents or proportions of powdered charcoal or other suitable carbon
I prefer to employ are about five to six but not more than about six of carbon
(when combined and mixed with the usual proportions of saltpetre and sulphur)
to two equivalents of saltpetre and one of sulphur to disengage from 12 to 14
volumes of gas instead of the usual 8. volumes.
Another useful and suitable proportion of ingredients for quick burning
powder for safety mining consists of not more than 84 parts and not less than
81 parts of saltpetre, in every 100 parts by weight of the finished gunpowder and
not more than 22 parts and not less than 19 parts of charcoal or suitable carbon,
with not more than one half part and not less than one quarter part of pure
sulphur the whole to be well intermixed or incorporated. To the finished powder
about one quarter to half an ounce of chlorate or perchlorate of potash, or other
oxygen giving substance is added to every four ounces of the finished powder,
the said substance being kept separate in a sealed case or tube. These gun-
powder proportions may be safely employed without the cooling salts, when
desired, in a meal or fine grain quickburning form, but the size of the grains
must be kept within the limits of safety for coal mine blasting.
For very
dangerous work, however, this combination gunpowder cartridge may be advan-
tageously combined for extra safety with a flame-cooling and fume absorbing
agent, embedded in the charge, but not intermixed therewith; or a safety
tamping pellet, case of the same substance may be employed instead, or for
absolute safety both may be used in conjunction. To secure a more simultaneous
and uniform decomposition of the cooling salts enclosed in tubes or cases and
containing either liquid ammonia or suitable cooling salts, such as ammonium
nitrates, oxalates, carbonates, sulphates, bi-carbonates, sodium carbonates and

page_text: the like, as described in the Specification of my Patent No. 9688 of 1893, in the
form of either a solution of suitable consistency or in a loose dry and crushed
or finely granulated state, and employed either separately or combined. This
method also applied to sealed tubes or cases of chlorate or perchlorate of potash,
or saltpetre, when combined with the meal or finely granulated explosives, when
in conjunction and embedded in the charge for obtaining simultaneous and
uniform decomposition or combustion, obtained by employing a length of delicate
copper wire which encircles the tubes or cases and holds them in position at the
desired points of the explosive charge in which they are embedded. For example
they are fixed on the wire at given intervals, say one cooler tube at the end or
bottom of the cartridge case with one in front, next to the neck or opening, and
with a tube or case of chlorate or perchlorate of potash, or saltpetre in the middle
of the charge. The copper wire is placed in the cartridge case, and the meal or
granulated explosive charge is run in, and surrounds the tubes; the outer end
of the copper wire is then tied in at the neck of the cartridge case ready for use.
By this improved method the tubes or cases are prevented from shifting, while
one cooler is rigidly kept in front of the explosive flame and the other retains
its position at the far-end of the charge, to prevent the flame from searching
back, without being cooled down; the incandescent flame is thus uniformly
cooled between two dampers, while the small charge of crushed chlorate or
perchlorate of potash, or powdered saltpetre secures additional strength and more
complete combustion of the explosive.
This object may be also efficiently attained by employing a small diameter
tube of nitrated cellulose paper the whole length of the cartridge case and choked
at intervals to form divisions for the cooling salts and chlorates; the ends of this
internal tube will be kept central by the disc hole at the bottom and disc cover
on the top of the explosive when securely tied in the case. Further, in lieu of
keeping the charges of cooling salts and the chlorates or perchlorate separate from
each other, as described, the two, if desired, may be combined as ammonium
chlorate or perchlorate in one case and uniformly embedded in the explosive
cartridge or charge.
The safety cap-cover, containing a circular hole for the fuse, and the disc of
tinned metal referred to, can be placed at the bottom and on the top of the
explosive charge, as described in the Specification of my Patent No. 16777 of
1897, may be thus advantageously employed and contribute to efficiently obtain
extra safety as I have proved in practice.
The safety metallic device for preventing blown-out shots, described in the
Specification of my Patent No. 9688 of 1893, containing a hole for the fuse, is
improved by simply using two light flat discs of tinned metal, connected by a
delicate rod of the same metal-i.e. tinned iron or steel-by being screwed or
riveted to each end of the said rod, but the device instead of being used entirely
in the interior of the cartridge case may be sometimes more conveniently used.
on the exterior of the case or charge when the bare point, or fuse hole end, of
the connecting rod, without the cap-disc fixed on the same, is forced up through
the bottom of the case and the disc firmly cemented there. The case is then filled
up with the combined charge, with or without the cooling tubes or cases tied on
the rod to hold them in position, similarly to the copper wire method, already
described; the cap-cover is then screwed down and riveted; the fuse-hole is closed
with a piece of damp-proof paper or calico cemented down, after which the case
with its contents is securely tied in at the neck ready for use. When such a
'case is employed the metallic cap-cover and disc may be used separated from
the rod instead: the cap-cover, with its turned-up edge, may be also efficiently
applied, especially upon the top of the pellet of damp plastic clay. When
tubes. or cases of ammonium salts are employed as cooling agents, for example
ammonium nitrate, it is of primary importance to keep the diameter of the tubes
or cases very small owing to the numerous modes of decomposition (seven accord-

page_text: ing to Bertholet). This applies whether the substance is employed in a firm
jelly like solution form, or in a crushed or finely granulated loose state, and also
to other ammonium salts or slow and irregular cooling substances; generally,
however, these smaller diameter tubes or cases are more suitable when employed
in this form, rather than in larger charges and less numerous. For uniform
safety they must be kept entirely separate from the explosive charge and not
intermixed, for retardation in combustion and decomposition is at once set up
if they are mixed, which is a fundamental error in making a true safety cart-
ridge for preventing the ignition of fire damp and coal dust in coal mines; even
a detonator cap which is usually employed to overcome this dangerous defect can
never be absolutely depended upon in practice.
To enable my invention to be fully understood I will describe it by reference
to the accompanying drawing, in which:-
Figure 1 is a longitudinal section of a țamping pellet-case having my improve-
ments applied thereto.
Figure 2 is a transverse section on the line 2-2 Figure 1.
Figure 3 is a longitudinal section of a compound carbonized meal guncotton
cartridge with tubes of chlorate and cooling salts made according to the invention.
Figure 4 is a longitudinal section of a compound carbonized meal guncotton
cartridge with tubes of chlorate of potash and cooling salts, combined with a
compressed guncotton pellet and detonator cap or a tube of chlorate of potash
made according to the invention and represented in a borehole; and
Figure 5 is a longitudinal section of a compound meal, fine grain, or quick
burning gunpowder cartridge in conjunction with cases or tubes of chlorates and
cooling salts combined with a pellet of compressed gunpowder and a charge of
chlorate or a detonator cap made according to my invention and represented in
a borehole.
Referring first to Figures 1 and 2 a is the cartridge case or wrapper containing
a bundle of tubes 6 of cooling salts and having six hollow central tubes e of a
combustible material, and a tubular passage d for the igniting fuse all being
closed in by a metallic cap-cover e and tied in at the neck f of the case a.
Figure 3 represents a longitudinal section of à carbonized guncotton cartridge,
a is the paper case which is tied at the neck f g is the charge of carbonized meal
or fine grain guncotton; h, h are two small tubes or cases containing ammonium
nitrate; and is a tube of chlorate of potash, each of which tubes contains a
hollow central tube j of combustible material. These tubes or cases are externally
connected by fine copper wire twisted round them to hold them in position, and
embedded in the carbonized meal guncotton g. 1, I are metallic cap-covers turned
up at the edge; one contains a hole for the fuse and they are both enclosed in
the case a and tied at the neck f along with the end of the copper wire ready
for inserting the fuse and placing in the borehole for firing the cartridge charge g.
Figure 4 is a longitudinal section of a borehole A containing a compound
carbonized meal guncotton cartridge, with two tubes or cases h, h of ammonium
nitrate and one of chlorate of potash embedded in the charge g.
central tube of combustible material run from end to end of the case a through
the tubes h, h, i. The charged tubes or cases h h and i are choked at intervals
as shewn at m, m to keep the cooling salts separate from the chlorate and are
held in position by the holes n, n of the metallic cap-cover and disc 1, 1 at the top
and bottom of the case and also by the neck f. The pellet o of compressed
guncotton is first placed at the far end of the borehole and may contain a
detontator cap p. (or a tube of chlorate) securely fixed in the central socket
holder q.
An internal
The firing fuser is then inserted in the cartridge case a through the hole in
the cap-cover and is tied in at the neck f of the case which is then placed in
the borehole upon the top of the compressed pellet o; an opening is freely made
in the bottom of the case to ensure a passage for the initial flame of
the

page_text: explosive to reach the detonator cap p. A pellet s of damp plastic clay is placed
upon the top of the cartridge case followed by the usual hard tampings after
which operation the cartridge may be fired.
Figure 5 is a longitudinal section similar to the above but in this example the
cartridge case a contains an explosive charge g of meal or fine grain quick-burn-
ing gunpowder in lieu of guncotton. The two tubes or cases h, h of ammonium
nitrate and the tube i of chlorate of potash are fitted and kept in position with
fine copper wire as described with respect to Figure 3; is a compressed gun-
powder pellet to the base end of which is fixed a metallic disc t¹. The pellet
contains a tube of chlorate in the central hole (or a detonator cap may be
substituted when desired).
The firing fuser is inserted in the cartridge case and the charge, including the
copper wire end, securely tied in at the neck f, as described with respect to
Figure 4, and placed in the borehole after which it is tamped in with plastic
clay and hard stemming as above described.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I wish it to be
understood that I do not claim generally the use of ammonium oxalate, ammon-
ium sulphate, or bicarbonate of soda, as a cooling agent in a blasting cartridge
containing gunpowder, but I declare that what I claim is-
1. The use for blasting, of a cartridge consisting of a charge of guncotton or
other suitable high explosive, in a meal or fine granular state, or in a com-
pressed form, combined with a charge of finely powdered charcoal or other
suitable carbon intermixed with the guncotton and fired by simple ignition or
otherwise, substantially as, and for the purpose, hereinbefore described.
2. The use for blasting, of a cartridge consisting of a charge of guncolton or
other suitable high explosive, in a meal or fine granular state, or in a com-
pressed form combined with a charge of finely powdered charcoal or other
suitable carbon in conjunction with charges of ammonium nitrate or other
suitable cooling salts, in a solution form of suitable consistency or in a finely
powdered or granulated state, confined in tubes or cases containing central tubes
of combustible material and held in position by copper wire or by an internal
tube, with, or without, a combined charge of chlorate or perchlorate of potash,
or saltpetre confined in tubes or cases in a similar manner and placed together
in the cartridge case and fired by simple fuse ignition or otherwise, substantially
as, and for the purpose, hereinbefore described.
3. The employment in combination with a carbonized blasting cartridge or
charge of the kind described in the two preceding claiming clauses of a com-
pressed guncotton pellet or other high explosive containing a detonator cap
(or in lieu thereof a sealed tube of chlorate or perchlorate of potash, or salt-
petre) placed at the far-end of the borehole and ignited by the carbonized meal
guncotton cartridge without any manipulation of the detonator, substantially as,
and for the purpose, hereinbefore described.
4. The use for blasting, of meal or fine grain quick-burning gunpowder, in
combination with tubes or cases of ammonium nitrate or other suitable cooling
salts and chlorates or perchlorates of potash, or saltpetre, employed and arranged
in the manner described in claiming clauses 1 and 2, or in the manner described
in Clause 3, wherein compressed gunpowder pellets or blocks are substituted for
compressed guncotton pellets, substantially as and for the purpose, hereinbefore
described.
5. The employment with cartridges of the kind described in the preceding
claiming clause of a tamping pellet-case or bundle of tubes containing cooling
ammonium salts or other suitable coolers, either in the form of a solution of
suitable consistency or in a powdered or finely granulated state, having internal
tubes of combustible material, and placed on the top of the explosive charge in
the interior of the cartridge case or used externally on the top of the cartridge or

page_text: explosive charge in the borehole, substantially as, and for the purpose, herein-
before described.
6. The manufacture and use of the improved blasting cartridges and tamping
pellet-cases herein before described and illustrated in Figures 1, 2, 3, 4 and 5,
respectively of the accompanying drawing.
Dated the way of December
G. F. REDFERN & Co.,
4, South Street, Finsbury, London.
Agents for the Applicant.