THE DETONATION OF GUN COTTON. 



By CHARLES E. MUNROE. 



(Read April 23, 1909.) 



In the use of gun cotton in mines or torpedoes, advantage is 

 taken of the discovery of Mr. E. O. Brown that gun cotton, which 

 is completely saturated with water, may be detonated by the deto- 

 nation of " dry " gun cotton in direct contact with it, for it thus 

 becomes possible to secure a large margin of safety for the naval 

 vessels carrying gun cotton torpedoes by keeping the major portion 

 of this cargo completly saturated with water so that it is immune 

 from the danger common to the powerful nitric esters of accidental 

 explosion through so-called " spontaneous combustion " while it is 

 still available for use at any moment as a detonating charge. It is, 

 in fact, as my experimental demonstrations have shown, an even 

 more efficient rupturing or shattering explosive than the same volume 

 of dry gun cotton is, the explanation of this increased efficiency 

 being found in the increased density, and therefore rigidity, im- 

 parted to the porous mass through its interstices becoming filled 

 with water. 



The blocks, or discs, as thus used, contained, on the average, 

 35 per cent, of water. In practice, this wet charge, in the service 

 torpedo, was fired or detonated by four 2-inch discs of " dry " gun 

 cotton, or its equivalent in |-inch discs or blocks, which was known 

 as the priming charge. As used the term " dry " meant air-dry and 

 necessarily referred to a variable condition dependent upon the 

 atmospheric conditions which obtained at any time and the exposure 

 of the primer to these conditions. 



It is desirable to know how reliable this system is and what 

 assurance may be placed in it. This may to a degree be determined 

 by ascertaining how much moisture the priming disks may contain 

 and yet detonate the wet gun cotton with certainty. It was not 

 feasible to carry this out on the large scale with charges of the mag- 



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