Year: 1886

page_text: I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention a communication to me from
abroad by La Société Scola et Ruggieri (Electricians) of 172 Rue Championnet
Paris France to be as follows:
This Invention relates to electric fuses chiefly intended for use in blasting, by
means of gunpowder or dynamite, in mines generally, but more especially in coal
mines liable to the presence of fire damp. These fuses entirely obviate the use of fuses
of all kinds which require to be ignited by a flame; they are also more economical,
and effect a great saving of time by preventing mis fires; while should the fuse
accidentally fail it can be immediately replaced without the liability of accidents,
such as are ordinarily caused in drawing the charges which can only be done after
a sufficiently long interval has elapsed. Morcover, as several shots can be fired
instantaneously, no loss of time is incurred by the workmen.
Reference is to be had to the accompanying drawing forming part of this
Specification, which illustrates an example of the Invention.
Figure 1 represents the plug used with the fuse of this Invention, with the
conducting wires attached. Figure 2 is a plan of the same, and Figure 3 a
horizontal section on line 1-2 of Figure 1. Figure 4 is a longitudinal section, .
and Figure 5 a longitudinal elevation of the fuse. The same letters of reference
represent the same parts in all the Figures.
The fuse is composed of a grooved wood plug 6 embraced longitudinally by the
conducting wires & which are first twisted together at the inner end of the plug
and then laid in the grooves c and twisted together at the outer end of the plug as
shown. The wires at the inner end of the plug are then flattened down. The
plug is enclosed in a paper sheath e, the charge of fulminate being filled into the
space fat the closed end of the sheath enclosing the twisted and exposed ends of
the wires. The electric spark produced on the passage of the current between
the ends of the wire ignites the fulminate. The electric fuse is introduced into a

page_text: tube a of copper or pasteboard provided with a quick match g which is ignited and
projected by the fulminate into the bore-hole and fires the charge of powder placed
therein.
For firing dynamite the fuse is modified as follows;-The pasteboard tube a is
dispensed with, and the plug is introduced into an ordinary detonating capsule
containing a fulminate. The electric fuse is separated from the fulminate by a
space of from four to six millimetres so as to avoid accident caused by friction or
otherwise. The capsule thus prepared is inserted in the charge in the ordinary
way; the additional advantage, however, being obtained of freedom from liability
of igniting the priming f which is the cause of so much loss of time and material,
as well as of danger when drawing mis-fires. The electric priming will in fact
either instantaneously produce an explosion, or not at all, and there will be no risk
attending the immediate renewal of the priming, or withdrawal of the charge.
Any kind of electrical apparatus may be employed for exploding these fuses, but
it is preferred to use one by means of which several shots, either or powder or
dynamite, may be fired simultaneously.
.
It will be evident that the herein described arrangements may be applied for
producing the ignition of a Bickford fuse which would, in this case, be substituted
for the quick match 9 in tube a thereby avoiding the use of a naked flame.
Dated this 12th day of March 1886.

page_text: An Improved Electric Fuse for Blasting Purposes.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention (a communication to me
from abroad by La Société Scola et Ruggieri (Electricians) of 172 Rue Championnet,
Paris, France), and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
This Invention relates to electric fuses chiefly intended for use in blasting, by
means of gun-powder or dynamite, in mines generally, but more especially in coal
mines liable to the presence of fire damp. These fuses entirely obviate the use of
fuses of all kinds which require to be ignited by a flame; they are also more
economical, and effect a great saving of time by preventing missfires; while should
the fuse accidentally fail, it can be immediately replaced without liability of
accidents, such as are ordinarily caused in drawing the charges, which can only be
done after a sufficiently long interval has elapsed. Moreover, as several shots can
be fired instantaneously, no loss of time is incurred by the workmen.
Reference is to be had to the accompanying drawing forming part of this
specification, which illustrates an example of the invention.
Figure 1 represents the plug used with the fuse of this invention, with the
conducting wires attached. Figure 2 is a plan of the same, and Figure 3 a
horizontal section on line 1-2 of Figure 1. Figure 4 is a longitudinal section,
and Figure 5 a longitudinal elevation of the fuse. The same letters of reference
represent the same parts in all the figures.
The fuse is composed of a grooved wood plug b embraced longitudinally by the
conducting wires d which are first twisted together at the inner end of the plug
and then laid in the grooves c and twisted together at the outer end of the plug as
shown. The wires at the inner end of the plug are then flattened down. The
plug is enclosed in a paper sheath e, the charge of fulminate being filled into the
space fat the closed end of the sheath enclosing the twisted and exposed ends of
the wires. The electric spark produced on the passage of the current between the
ends of the wire ignites the fulminate. The electric fuse is introduced into a
tube a of copper or pasteboard provided with a quick match g which is ignited
and projected by the fulminate into the bore-hole and fires the charge of powder
placed therein.
The above arrangement may, however, be modified, for example, two parallel
wires might be used twisted together or not, at the ends.
For firing dynamite the fuse is modified as follows; The pasteboard tube a is
dispensed with, and the plug is introduced into an ordinary detonating capsule
containing a fulminate. The electric fuse is separated from the fulminate by a
space of from four to six millimetres so as to avoid accident caused by friction or
otherwise. The capsule thus prepared is inserted in the charge in the ordinary
way; the additional advantage, however, being obtained of freedom from liability
of igniting the priming f which is the cause of so much loss of time and material,
as well as of danger when drawing miss-fires. The electric priming will in fact

page_text: either instantaneously produce an explosion, or not at all, and there will be no risk
attending the immediate renewal of the priming, or withdrawal of the charge.
Any kind of electrical apparatus may be employed for exploding these fuses, but
it is preferred to use one by means of which several shots, either of powder or
dynamite, may be fired simultaneously.
It will be evident that the herein described arrangements may be applied for
producing the ignition of a Bickford fuse which would, in this case, be substituted
for the quick match g in tube a thereby avoiding the use of a naked flame.
Having now particularly described and ascertained the nature of the said
Invention, and in what manner the same is to be performed, I declare that what.
I claim is:
An electric lighting fuse or "lighter" for blasting purposes, denominated the
Ruggieri fuse, consisting of a guide tube a, grooved wood plug b, conducting
wires d, fulminate f, and quick match g, the grooved plug and conducting wires
being enclosed in a paper or other sheath or cap to contain the fulminate, and the
whole being enclosed within the tube a, substantially as shewn and described.
Dated thin 17th dose of A7000