110 THE CHEMISTEY OF COLLIERY EXPLOSIONS 



disruptive energy, to the mutilation of men and destruction 

 of the mine. These effects were limited to the immediate 

 vicinity of the explosive mixture; but the phenomena of 

 explosion were found for thousands of yards beyond, where 

 firedamp could not be conceivably present. The ignition of 

 the firedamp may have been the initial cause of the explosion, 

 but the extensive phenomena beyond, demanded for their 

 explanation an explosive agent of coextensive distribution. 

 Investigation has shown that coal-dust was universally pre- 

 sent, and the only agent capable of giving rise to explosion. 



Faraday and Lyell examined the Haswell Colliery after 

 the explosion there in September, 1844, and in their report 

 to the government they said * : "In considering the extent 

 of the fire from the moment of the explosion, it is not to 

 be supposed that firedamp was its only fuel ; the coal-dust, 

 swept by the rush of wind and flame, would instantly take 

 fire and burn, if there were oxygen enough present in the 

 air to support its combustion ; and we found the dust ad- 

 hering to the faces of the pillars, props, and walls. This 

 deposit adhered together in a friable coked state. When 

 examined with the glass it presented the fused round form 

 of burnt coal-dust ; and when examined chemically, and 

 compared with the coal itself reduced to powder, was found 

 deprived of the greater part of its bitumen, and in some 

 instances entirely destitute of it. There is every reason to 

 believe that much coal gas was made from this dust in the 

 very air itself of the mine, by the flame of the firedamp 

 which raised and swept it along, and much of the carbon 

 of this dust remained unburnt, only from want of air." 



" In January, 1845, Faraday delivered a discourse at the 

 Hoyal Institution, in which he dealt with this Report, and 



* Final Report of Boyal Commission upon Accidents in Mines. 

 pp. 30, 31. 



