The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1880-11-24
The Fatal Fire-Damp in Coal
Mines,
Boston Transcript

The gas which causes these dreadful catas-
trophies is carburetted hydrogen. called by the
miners "ire-damp" or sulphur" 1t is found
in nearly all coal mines. but some produce 1t
in much greater quantities than [others, and
the thin, deep-lying, bituminous beds of Great
Britain yield it in a greater quantity than any
Others while those Of Belgium and France
come next. American mines are compara-
lively free from it, its victims being numbered
by units where in England they are numbered
by scores. This gas appears to be generated
by slow decomposition Of the carbonaceous
matter. 1t permeates the coal in the vein and
fills the cracks and cavities that usually exist
in overlying rocks. 1t is often packed in these
assures under such strong pressure that 1t
causes scales of coal to fly off from the face of
the works, and escapes with a missing or hum
ming noise. Sometimes q cavity is tapped by
the miners pick which sends forth q stream
of gas like that from broken house-main.
This is called blower" and is frequently
lighted by the miners, when it is safe to do SO,
as it will often burn for q long time, giving
them additional light to work by. Fire-damp
is but little more than half as heavy as COM
mon air, and If the working were open to the
as it would fly away and be dissipated as fast
as it rises. But 1t cannot fly farther than the
roof of the mine, and SO it collects there, fill
ing the cavities from which masses Of "top"
have fallen, gathered in worked-out and aban-
doned breasts, and constantly accumulating,
unless driven out by the only adequate force, q
strong and we'll directed current Of fresh air.
Pure tire-damp is not infammable and will
not explode, but will instantly extinguish a
light. To make it explosive it must be mixed
with at least six times its bulk OF air, and
when diluted with fourteen times its volume
of pure air it becomes too weak to explode;
while its explosive force varies with the pro-
portion of the mixture within these two limits,
being greatest when the proportion Of air to
gas is about one to ten. In this condition it Is
a terrible thing. When lighted 1t expands
suddenly and violently to 100 times its former
bulk, exerting pressure of 200 pounds to the
square inch on all solid bodies that may be in
its way. and reaching temperature Of 1902
Fahrenheit.
But what fires the gas? A spark will not
do it, for before the safety,lamps were invented
"fery" workings were lighted by means of
steel wheel, which revolved against o flint
and struck out stream of sparks, q very poor
light indeed, but that Of the safety lamp is not
much better. Miners will run heavy risks
with a naked light rather than work by the
feeble glimmer Of "Davy," which is q sickly
flame at best, and is further obscured by
screen of closely-woven wire gauze. So they
work with naked lights, and by-and-by one Of
them carries his lamp into a higher part of
the mine, and portion Of roof falls near
them, and brings down the gas that had
lodged under it, and an explosion follows. Or.
perhaps a miner who has been forbidden ma
k, d lamp, thinks there is no danger, and opens
his safety lamp to get the benefit of its unob-
sructed light. Or, though he knows there Is
danger, he thinks he can open his lamp long
enough to get light for his pipe. One of the
Ornat RiaCa ayplOSiOng causad in this
Or he carelessly hangs up his lamp while he
digs in a position where his pick presently
strikes it, and knocks hole in the gauze--
which is believed to have been the way the
Risca explosion of last July was caused. Or
the lamp itself may have fred the gas without
being tampered with by the miner. The the
ory on which most safety lamps are based is,
that flame will not pass through q small aper-
ture, and hence the sides of the lamp are made
of wire gauze so closely woven that flame will
pass through the meshes. In an explosive
mixture of gas and air, however, the space
inside the gauze is filled with gas, which burns
as freely there as it would anywhere else, and
generates heat which very soon makes the
gauze red hot, and before very long burns
through the wires, leaving the flame unpro-
tected. Or, If the lamp is moved through an
infiammable atmosphere at rate Of speed
greater than eight feet per second the flame
will be forced through the meshes by the We
locity of the movement. A recent explosion
IN England was caused Dy boy VINO walked
at the rate of five feet per second against an
air current heavily charged with gas, which
was flowing at the rate Of eight feet per sec
ond; and in a Schuylkill County mine last
year two men were killed by an explosion
while running away from strong "blower" Of
gas which they had suddenly struck while
working. They had safety lamps, and one OF
them took the precaution to shield his lamp,
with his coat; but the other carried his in his
hand, and his movement caused it to fire the
gas.
Stellarton, which is the scene of the fright
full mining disaster Just repeated, is mining
village in Pictou County, Nova Scotia, on
East river and on the Intercolonial Railway,
one hundred miles northeast of Halifax and
six miles from Pictou Harbor. The place
often goes by the name of the Albion Mines.
Great quantities of coal are raised from these
mines. The village contains numerous stores
and a telegraph office 1t has population OF
20O0