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10 COAL AND TIMBER January, 1905
serious results so far as the writer knows,
in the several Bituminous Inspection Districts.
I will cite a case that came under
the writer's personal observation, where
the loader, as soon as the machine had
finished undercutting his room and had
been moved to the next room, he, the
loader, got down on his knees on the road
side, scraped away some of the dust from
face of undercut to look in under to see
if r.he machine had left in any stumps or
unc.it coal and with his open light attached
to his cap on his head, looked in under with
the result that the finer particles of dust
set a flame, burning him severely. This
occurred about 11 o'clock A. M. and there
was no gas in the room. If there had
been, the driver, operator and helper, as
well as the loader, would have found it
sooner as they all four were using open
lights and upon examination of the Fire
Boss' reports, no gas had ever been reported,
so that it is evident in the writer's
opinion, that the fine particles of coal dust
set aflame by coming in contact with the
open light as used by the said loader, Fire
Damp being absent. In questioning the said
loader, his version was that it went off like
a flash of blasting powder.
Now, if you will permit me to digress
a few moments and take a view of the reports
of some of the British Mine Inspectors
for recent years, also of our own
Bituminous Inspectors' reports, as in the
writer's opinion this paper would be incomplete
without them, as they bear so
closely to the subject under consideration
and attention should be drawn to some of
them as they contain several references to
the part played by coal dust in some recent
explosions. April 30th, 1875, an explosion
occurred at the Bunkers Hill Colliery,
wdiere 49 men lost their lives, caused by a
blown out shot igniting the coal dust which
in turn communicated with a pocket of gas
supposed to be back some distance from
the face, as the working face was considered
safe for to fire the shot, this heading or
entry, being ventilated by a pipe one foot
in diameter.
Brannpith Colliery, Durham, April 24th,
1889, explosion caused by an open torch,
used by workmen in cleaning out hoppers,
in which three men lost their lives.
Mossneld Colliery, October 16th, 1889,
on which the Inspector says this disaster
is another example of how an explosion
is extended by coal dust. The loss of life
and property being greatly increased as a
consequence.
Hubburn Colliery, November 4th, 1889,
in which the inspector says he does not
feel justified in calling it entirely an explosion
of Fire Damp, as the shot hole was
charged with gelignite and roburite together
and in the inspector's opinion this
explosion was caused by the flame blown
out from the fast shot, assisted by any
small quantity of Fire Damp that may be
present.
Particulars of another example of Coal
Dust exploding without Fire Damp which
occured in 1890 at one of the Collieries
in the Yorkshire District. Some very
fine coal dust had accumulated on a plank
which it was necessary to remove to make
some repairs to the engine; in turning the
plank over, the coal dust fell upon a torch
light below and an explosion occurred,
burning several men severely. Also recent
reports of the Inspectors in the different
States have drawn attention to the serious
effect coal dust has in propagating an explosion.
The Inspector for the Second
Bituminous District in his report for 1891
recommended that coal dust of dry mines
be dampened; also the report of the several
Inspectors on the late Harwick disaster
says they agree that the cause of the explosion
was the result of a blown out shot,
and that the sprinkling and the laying of
the coal dust according to rule 60 had been
neglected. Also, they found that in several
parts of the mine the heat had been
intense, coking the coal and dust. And,
further, the report says we can readily see
that the explosion could be transmitted
from one point to another by the Carbonic
Oxide distilled from the coal dust which
had been suspended in the atmosphere of
the mines, thus exploding the accumulation
of Fire Damp and coal dust along the path
of the explosion, carrying death and destruction
into every nook and corner of
the mine. In viewing over the different
causes of explosions, on the one hand I
find that the largest and most destructive
explosions have occurred in mines whicli
are more or less fiery, and on the other
hand, no very large explosions have ever
occurred in a very wet mine, which tends
to show that coal dust plays some important
part in the extent of an explosion.
From experiments made by Mr.W. Galloway
(whose name will always be honorably
associated with this matter) proves
beyond a doubt that the existence of Fire
coal dust in fiery mines is a dangerous
element and that it has played an important
part in Mine explosions. It has been
stated that if a small' quantity of Fire
Damp be present and fired that its effects
are much intensified and the explosion is
extended along the roads containing coal
dust, thus feeding the flames of the explosion
and that these facts are now fully
recognized is evident as per rule No. 60 of
the Bituminous Mine Law which reads :
'• In mines where coal dust has accumulated
to a dangerous extent, care shall be
exercised to prevent said coal dust from
floating in the atmosphere by sprinkling it
with water or otherwise as far as practical.
It is now very evident that a blown out shot
will raise the dust and set it aflame and for
evidence in this will cite a case when Mr.
H. Hall, Inspector of Mines for the Liverpool
District, reported by him to the Secretary
of State, January 23rd, 1893, says in
part that a charge of blasting powder was
fired by electricity from a cannon, suspended
in a wet shaft, the air of which was
proved by careful chemical analysis to be
absolutely free from any trace of inflammable
gas, and in some of the experiments,
even in the absence of dry dust in suspension
in the shaft, that the dust lodged on
the timbers was exploded by firing V/2 lbs.
of gunpowder from the cannon. Mr. Galloway
says that one per cent, of Fire Damp
when properly mixed with very fine coal
dust and air forms an explosive mixture,
while Sir Frederick Able states that from
2 to 2.'^ per cent, of Fire Damp is needed.
In the writer's opinion, after glancing over
the several reports of Mine Inspectors and
in viewing over the results of experiments
made in the past, the following conclusion
may be drawn : First—Coal Dust is
not completely burned in flaming air.
Second—And that if a high charge of coal
dust is inflamed at one point, the carbonic
oxide produced becomes a transmitter of
flame to another point. Third—And that
in case we need to use a very strong current
of air for the removable of gas, this
strong current would raise the dust lodging
on the timbers or along the floors or
sides of airways and carry it in suspension
and whiie the gas being removed may of
itself not be sufficient when mixed with air
to make an explosive mixture, yet with the
addition of coal dust a very explosive mixture
may be generated and if any kind of
flame came in contact with said mixture a
very disastrous explosion would occur.
The question naturally arises, what means
or methods should be applied to remove
this agent of destruction from our midst?
Some have proposed covering the roads
with common salt believing that it would
retain a continual dampness being delignescent
or an absorber of water. Nitrate
of Soda has been proposed and tried for
the same purpose, wetting the roads with
streams of water has been tried, but from
some cause or other these methods have
either entirely failed or partially so. In the
writer's opinion, the coal dust should be
loaded and taken out of the mine as far
as practical, yet in doing this the dust in
transit along the haulage roads in the
mine wagons would leak out through the
crevices of said wagons on the road as in
our improved systems of transporting the
coal from the face to tipple, the trains are
run at a great speed and the dry coal and
coal dust carried in the wagons is subject
more or less to jolting and jarring and the
dust leaking out gradually settles on
some part of the haulage, the finer particles
remaining longer in suspension settling
for the most part on the timbers and sides,
and if an explosion should occur in any
one district of the mine and the dust deposited
on haulage or other districts may
not be set aflame, yet the dust will be much
more violently agitated and the atmosphere
become so impregnated with the dust, as to
render it fatal to any one inhaling it while
trying to escape from the mine, not having
been affected by the said explosion in the
other district. To keep the haulage ways
as free as practical from this danger a water
wagon attached to the rear end of trips
going in or out of mine, preferably behind