COAL AND COLLIERY EXPLOSIONS. 
361 
can be little doubt, and it becomes an important matter for con- 
sideration, whether a system of watering dry pits ought not to 
be adopted. On the other hand, many explosions take place in 
damp pits, as the Queen Pit, at Wigan. 
Few accidents probably occur from the use of gunpowder 
properly applied, no flame resulting from a shot which takes 
effect ; but when the tamping is defective, from bad workman- 
ship, or from a very hard rock, the shot is blown out like the 
bullet from a gun, fire-damp dislodged by the vibration or 
fall of roof may be directly ignited by the flame of powder gas 
issuing from the hole, or it may be driven by the sound wave 
through the meshes of a distant safety lamp : to the latter cause, 
which has been carefully investigated by Mr. Galloway, the 
firing of the larger number of explosions is doubtless due. But 
the Haydock accident proves that if ever the use of powder were 
discontinued altogether, this class of accident would still con- 
tinue ; for here the gas was ignited by the men simply by run- 
ning against the stream of gas-laden air. Many days after the 
explosion, Evans and Clare’s place, six or seven yards from the 
Downall Green Fault, still received so large an amount of gas 
that, on turning the ventilation away from it, it filled with ex- 
plosive gas in four minutes, or 1,250 cubic feet of gas a minute, 
and lamps fired on the spot, when 13,600 feet of air played on 
it. 
In the opinion of the Government Inspector, this explosion 
was not due to the “ blower ” of gas, but to fire-damp issuing 
from the adjoining old workings, the edge of which was swept 
by the ventilation, and which it visited first, travelling in all 
300 yards from the bottom of the downcast shaft to the bottom 
of the upcast, supplying 200 men, and 11 horses, the amount 
being 28,000 feet ; but this quantity is equivalent to a much 
larger amount in a colliery in which gunpowder is used, which 
was not the case in the Wood Pit. 
By the Coal Mines Act, the inspection of every mine in 
which gas has been seen within twelve months has to be carried 
out every twenty-four hours, before the men enter, when one 
shift are working, and every twelve hours when there are two. 
All workmen are to be withdrawn when noxious gases prevail, 
and the place inspected. No lights but locked safety lamps are 
to be used in places where gas is likely to accumulate. Gun- 
powder is not allowed to come into a mine in more than 4-pound 
canisters, nor more than one canister to be in one place at a 
time. Iron or steel is not allowed to be used for charging holes 
for blasting. 
When gas has been present during the past three months, 
cartridges are alone allowed to be taken into the mine, and may 
only be fixed by the proper official, and if a blue cap appear on 
