Explosions in Coal Mines. 19 



Before going into a particular consideration of the causes 

 of the late accident at Haswell, and the possible means of pre- 

 venting the recurrence of the like in future, we wish to point 

 out the fact well known to the viewers in this district, that the 

 pits on the north side of the Wear, in which the Hutton seam 

 is worked, are more infested with fire-damp than those on the 

 south side of that river. If, therefore, at Haswell Colliery, 

 situated among the latter, the danger has proved to be so great, 

 still more necessary will it be to endeavour to take additional 

 precautions elsewhere. 



There can be no doubt, that as regards the safety of the men 

 in coal mines from injury consequent upon fire-damps, venti- 

 lation is of the utmost importance, but there is a practical 

 limit beyond which it cannot be carried, for in works deep and 

 extensive, as the coal mines often are, to dig shaft after shaft 

 would quickly involve an expense more than the value of the 

 produce of the mine, and have the effect of closing it altoge- 

 ther. There is one point in ventilation, however, which, at 

 the same time that it appears to us capable of improvement, 

 touches a part of the mine of the utmost consequence to the 

 safety of the whole ; and though our observations and thoughts 

 are not founded upon long experience, or the examination 

 personally of many mines, yet considering that the one we 

 have so recently been called to observe is as simple in the 

 character of its workings, contains as small a proportion of 

 fire-damp, and is as well-ventilated as any in that part of 

 England, surpassing in these respects most of the mines, we 

 do not think that they will be exaggerated in respect of, or less 

 applicable to, other cases. We allude to the ventilation and 

 general character of the goaf. 



The goaf is a mass of ruins in the middle of the works, 

 growing from day to day, as the workings of the mine extend. 

 The miner, as he works in the undisturbed coal (which is 

 called the "whole), removes it, so as to form passages which are 

 usually parallel to, and at right angled* with, each other; the 

 square portions of coal left between them are called pillars ; 

 the passages or ways are, upon the average, about 5 yards 

 wide, and the pillars are about 16 yards by 22 yards; the 

 pillars, whilst they remain, support the roof, and the super- 

 incumbent rocks and strata; this part of the works is called 

 the broken. 



Afterwards the coal of the pillars has to be removed, and 

 as it is carried off, the roof so exposed is supported by many 

 wooden props; this state of things constitutes a jW: at last 

 these props are withdrawn, and this is called dramng ajud\ 

 during or after which the roof falls in masses, larger or smaller 



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