TRANSACTIONS OF THE SECTIONS. 53 
On the Methods of Working and Ventilating the Coal-mines of the North of 
“England, with reference to the Accidents that occur in such Mines from the 
“Explosion of Firedamp. By Professor Anstrep, M.A., F.R.S., Vice- 
tel Gray OCs 
\The object of this communication was partly to explain the methods of working 
‘coal adopted in the Newcastle coal-field, and partly to suggest certain methods 
which, in the author’s opinion, were calculated to diminish the risk of accidents 
arising from the explosion of firedamp, without interfering with the ceconomical 
working of the mines. 
In the district in question, the extent of coal worked by one company and from a 
single pair of shafts is very considerable, amounting, in fact, in some cases, to as much 
as 1000 acres. The depth of the sinkings is enormous, being rarely less than 150 
fathoms, and sometimes upwards of 300. The competition amongst the various 
proprietors is very great, and the expense of sinking such deep shafts, often through 
untried ground and with a vast body of water pouring in from quicksands, is so 
enormous, that there seems no hope of adding very considerably to the number of 
the shafts in each mine; ner does the author consider that to increase this number 
beyond certain limits would diminish to any extent the danger of explosion. 
The coal in the north of England and elsewhere is well known to give off during 
working a considerable quantity of light carburetted hydrogen, and occasionally, it is 
supposed, a smal] quantity of olefiant and sulphuretted hydrogen gas, and when the 
gases thus given off are mixed with a certain quantity of ordinary atmospheric air, 
they become highly explosive. 
The ordinary processes of ventilation, effected by placing a furnace at the bottom 
of one shaft, or one compartment of a shaft, and thus causing a current of air to 
descend another shaft, and move with a regulated rapidity through all the work- 
ings, were described by the author as sufficient for the carrying off the gases thus 
liberated under ordinary circumstances; but besides these there are occasionally 
met with sudden and violent puffs of gas, called blowers, proceeding either from 
faults or from cavities in the coal, and against them no process of ventilation is a 
sufficient safeguard. Owing also to the nature of the associated strata, and the 
great depth of the workings, it happens that when workings have been carried on to 
any extent under ground, a considerable portion of the district left empty by the 
extraction of the coal is partially filled by the broken roof, which, however, not 
occupying the space entirely, affords cavities, sometimes of great size, into which the 
lighter inflammable gases naturally collect, and there become slowly mixed with at- 
mospheric air. Such cavities therefore are often full of explosive mixture, ready to 
take fire at any instant, and occasionally, owing to a change in the pressure of the 
air, or from other causes, the explosive mixture actually emerges into those pas- 
sages in which open lights are used and causes accidents. Each of these spaces, 
filled with rubbish, and thus forming a magazine of foul air, is called, technically, a 
oaf. 
f Referring to the explanation of the nature and action of the goaf, as given in the 
“Report on the Haswell Explosion’ by Messrs. Lyell and Faraday, the author ex- 
pressed his opinion that in the north of England there is not such a degree of 
regularity in the mechanical limits and condition of this goaf as would admit of any 
separate system of ventilation or gas-draining for such parts of a mine, and he also 
urged that the rise side of the goaf was by no means always the place of danger, or 
the origin of accidents in the greater number of instances, 
__ The author then suggested the following methods to be generally introduced in 
working coal mines :— . 
1. Lhe having at least two shafts in each colliery.—This is absolutely essential, and, 
though generally acted on, requires to be enforced in every instance, since in case of 
an accident in a mine with only a single shaft, it is extremely probable that the par- 
_titions at the bottom will be blown away, and thus all those persons employed in 
_ parts which the explosion has not reached will almost necessarily perish, since the 
_ventilation is instantly stopped by the accident, or only the poisonous air called 
_ ofter-damp circulates through the workings. Besides this there are many accidents 
to which a pit is liable, such as the falling in of brick-work, &c., which, by pre» 
