184 Air. Bubdle's Accoimt of the Ecvplosion in Jarrow Colliety. 



No. XX. — An Account of the Explosion which took place in Jarrow Col- 

 liery, on the Sd of August last. By John Buddle, Esq. 



Read, October 18, 1830. 



It seldom happens that the immediate causes of those fatal explosions, 

 which so frequently occur in the Coal-mines of this country, can be 

 clearly ascertained ; as those individuals, who alone could explain 

 them but too frequently fall victims to their destructive effects. 



The proximate causes are, however, well known ; but before I ex-, 

 plain the nature of them, it may not, perhaps, be deemed irrelevant to 

 state the general circumstances of our fiery collieries. 



Those collieries, to which the appellation "fiery," is given, are such 

 as abound in inflammable air, in a greater or less degree. The inflam-. 

 mable air is evolved from the Coal, in the working seams, or from 

 seams lying above, or below, those which are in work. 



The inflammable air thus evolved, is either immediately diluted be- 

 low the explosive point, and carried away by the circulating current of 

 atmospherical air, employed in ventilating the working seams ; or it 

 accumulates, in any fissures or cavities which may happen to be in the 

 roof or pavement of these seams, or in the fissures of the Coal. 



The state of the atmosphere, has great influence on the discharge of 

 the inflammable air from the Coal in the ordinary workings of a colliery ; 

 its discharge being materially controlled, and regulated by the vari- 

 ous degrees of density of the atmosphere. As, for example, if the or- 

 dinary ventilation of a pit's workings, should only be just adequate to 

 the dilution of the quantity of inflammable air evolved, below the firing 

 point, when the barometer stands at 30 inches, it would become quite 

 inadequate, whenever the barometer falls ; and on the contrary, if the 



