SOME MODERN DEVELOPMENTS IN METHODS OF TEST- 

 ING EXPLOSIVES.^ 



[With 12 plates.] 



By Charles E. Munroe, 

 Professor of Chcmistnj, George Washington University. 



As has previously been pointed out in these pages, the greater pro- 

 portion and the larger variety of the explosives that are annually 

 produced are consumed in the industries, and a very considerable pro- 

 portion of these are consumed in the winning of coal. As is well 

 known, this most important industry is attended by many hazards, 

 not the least of which is the constant danger of explosions owing to 

 the presence of fire damp and inflammable dust in these mines. Most 

 serious accidents from these causes, which have been attended with 

 frightful casualties, have frequently occurred, and their frequency 

 and magnitude have increased as the demand for coal has increased 

 until the public conscience has been aroused and efforts have been 

 made by individuals and by governments to devise means by which to 

 reduce the number of these explosions and limit their scope. 



Consideration of the conditions attending such of these catas- 

 trophies as were carefully investigated made it evident that many of 

 these mine explosions have been initiated by the explosives used in 

 the mines, and therefore the behavior of a large variety of explosive 

 compositions, when fired in dusty and fiery atmospheres, have been 

 studied experimentally with a view to selecting from among them 

 those which, while capable of doing the work reqiiired of them effi- 

 ciently at a reasonable cost, and while possessing such qualities as to 

 render them reasonably safe in transportation, storage, and use, were 

 least liable to ignite the fire damp, or coal-dust-air mixture, or mine- 

 gas-coal-dust-air mixture found in mines. 



For this purpose it became necessary to have a chamber in which 

 the gas and dust could be introduced, and the explosive fired, at will, 

 and all the conditions of the experimental trials be known and under 



1 Reprinted by permission from the United States Naval Institute Proceedings, vol. 36, 

 No. 3, whole No. 135. Copyright, 1910, by Philip R. Alger, secretary and treasurer 

 United States Naval Institute. 



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