AN IMPROVED NETHOD OF AND MEANS FOR DESTROYING FIRE-DAMP IN MINES
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at the
Office of the Commissioners of Patents on the 8th September 1880. A com-
munication from abroad by Robert Blacklidge, of Enfield, in the County of
Hartford and State of Connecticut, United States of America, Miner, and
Albert J. Battles and George Wilcox, also of Enfield, in the County of Hartford
and State of Connecticut, United States of America, Trustees of the Church
Family of Shakers.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "AN IMPROVED NETHOD OF AND MEANS FOR
DESTROYING FIRE-DAMP IN MINES." [A communication from abroad by Robert
Blacklidge, of Enfield, in the County of Hartford and State of Connecticut, United
States of America, Miner, and Albert J. Battles and George Wilcox, also of Enfield,
in the County of Hartford and State of Connecticut, United States of America,
Trustees of the Church Family of Shakers.]
When fire damp or carburetted-bydrogen has accumulated in large quantities in
a mine it has been the custom heretofore to vacate the mine and fire the gas. This
process is ordinarily attended with great danger, and it has been found that the
gas when lighted will in most cases where the gas is heavy first burn slowly, and
as the flame increases in volume the gas will become highly heated from contact
therewith, and being driven into a confined space will be caused to explode with
great violence, and will destroy the timbering of the mine and choke up its passage
with debris, which will render them inoperative, and oftentimes result in the loss
of life. This danger it is desired to overcome by the employment of a great number
of separate flash torches or rockets, that are to be distributed over the mine in
various places wherever the gas may be accumulated, and that may be lighted at
such points simultaneously or in quick succession, so that the gas will be lighted
at a new point before the flame from the first point lighted shall have reached the
second point. By this means the gas may be ignited at the farthest point from
the pit's mouth first, and carry the gas flame, after damp, and smoke forward
towards the mouth of the pit or the nearest draught outlet, where the greater part
of the poisonous gases of combustion and the gases remaining unconsumed will
escape with the draught harmlessly.
The rocket constructed according to this Invention consists of a lath or strip of
wood of sufficient length to extend from the floor to the roof of the mine, or nearly

page_text: thereto, having secured to its upper end a piece of fuse saturated with nitrate of
potash, and of sufficient length to burn from one end nearly to the other within a
period of time sufficient to enable the man who fires them to escape to a place of
safety in a well known manner. The upper end of the fuse is wrapped around the
head of a match, preferably formed of inflammable material other than sulphur,
which will become ignited with a quick flash of flame and will not throw off fumes
of sulphur when lighted.
The fuse and match are secured to the end of the wooden strip by means of
carpet tacks or in any convenient manner. Instead of employing a stick to hold
the match and fuse in proper position against the wall rock, a little damp. clay may
be employed, which will stick to the wall and hold the match and fuse in place.
In order to prevent the wet clay from damaging the fuse and match they may be
first covered with a water-proof wrapper. The bright flash caused by the ignition
of the splint match will quickly light the fire damp, and as very many of the
rockets are employed the use of sulphur tipped matches should be avoided, as the
fumes of the sulphur from many matches would vitiate the air and could not be
readily freed from the mine. In operation when the mine shall have become
poisoned with gas and it is proposed to have a "clean up" the foreman dispatches
a number of men, each with a quantity of rockets, to properly dispose of where the
gas is collected. The rockets by means of their sticks may be propped against the
walls so that the fuse and splint match will be held closely to the hanging wall or
-roof-of-the-mine,-or-may-be.held.in.such_position_by_the_clay.
The rockets nearest the face of the mine are first lighted by means of a wire
heated by passing it through the gauze of a Davy lamp, and the rockets-are-lighted
in regular succession as the collier retreats to the mouth of the pit. The gas will
thus be readily consumed by many flames before it can be heated and rarefied to
an exploding temperature. The fuses may be so timed that they will light the
match at suitable intervals, and when sufficient time has elapsed for the inen to
escape to a place of safety. Experience in burning and destroying fire damp in
mines has shown that the gas is in most cases heavy and slow to burn, and when
lighted will burn at the rate of about 25 fect in a minute, so that ample time will
be given for it to be fairly lighted at different points, to be consumed in separate
flames. It is considered best to so time the fuses that they will ignite the gas at
different points successively at such intervals of time that the volumes of gas
ignited from one place shall fairly start in motion towards the pit's mouth or the
natural draught outlet of the mine before the next succeeding match is lighted, and
it has been found that the flame, unconsumed gas, and products of combustion will
by this simple means be started in motion towards the pit's mouth or in the
direction of the draught outlet of the mine, where the greater portion of it will
harmlessly escape. The remaining noxious gases may then be absorbed and
driven off by the natural draughts of pure air through the mine.