DUE TO GAS DEEIVED FEOM COAL-DUST. 113 



adequate cognizance of the fact that the energy of coal-dust 

 in combustion does not, like that of a blasting material 

 or an explosive substance, reside in the inflammable body- 

 alone, but in a system composed of coal-dust and the air 

 necessary to burn it. Coal-dust can only be an explosive 

 agent by virtue of the combustible gases it yields by dry 

 distillation. When the distillation is conducted with the 

 coal-dust in atmospheric suspension, at a temperature at 

 which the educts can enter into combination with the 

 atmospheric oxygen, the gases are burned immediately upon 

 their liberation, producing flame, but no disruptive energy. 



The explosions in mines caused great destruction ; men 

 were found literally blown to pieces, and tunnels wrecked, 

 exhibiting the effects of forces of disruptive energy, which 

 were unaccounted for in the theory of combustion referred 

 to. 



The explosions were found to have been propagated from 

 the point of origin to remote places in the mines, and 

 Messrs. Hall and the Atkinsons, H.M. Inspectors of Mines, 

 advanced an hypothesis of a travelling blast, while Pro- 

 fessor Dixon adopted the term of '' a flame," rushing along 

 each path of propagation. Numerous disruptions were, 

 however, found in these paths, and, at their loci, the broken 

 and displaced materials were observed lying in opposite 

 directions ; e.g.^ at Timsbury collieries a wagon was found 

 broken up, — one end was discovered inwards, the other 

 outwards.* At the Albion Colliery a train of wagons 

 standing in a siding was divided about the centre, and the 

 two parts were discovered some distance from each other, 

 one portion in the eastern entrance, the other in the western 

 entrance of the siding.f This phenomenon was frequently 



* The Origin and Rationale of Colliery Explosions, p. 15. 

 f lbid.,-ip. 76. 



