70 



MUNROE— DETONATION OF GUN COTTON. 



[March s, 



nitude used in torpedoes, nor did it seem necessary to the solution 

 of the problem that this should be done. As I have previously 

 shown, such tests may be made upon single unconfined blocks or 

 disks of wet gun cotton, resting upon rigid iron supports, the evi- 

 dence of complete detonation being found in the impressions left 

 upon the iron support with which the explosive is in contact, and 

 this method was resorted to in this instance. 



In carrying out the tests steam-dried blocks of gun cotton, which 

 were to be used as priming charges, were carefully weighed. They 

 were then immersed in water for awhile and again weighed, the 

 increase in weight showing the amount of water that had been 

 absorbed by each priming block. Immediately after weighing, and 

 before evaporation from the primer could take place, these primers 

 were placed, one after the other, upon blocks of saturated " wet " 

 gun cotton and fired by the service detonator, containing 35 grains 

 of mercuric fulminate, in the usual manner. The results of the 

 trials are set forth in the following table, in which they are arranged 



