Decomposition by Shock of EndotJiermic Compounds. 1 5 



In order to fire the fulminate at a given moment, the 

 detonator was fastened by a caoutchouc ring in the end of 

 a firing tube filled with electrolytic gas. This firing tube 

 was screwed into the bomb, so that the detonator on one 

 side was in contact with the electrolytic mixture, and on 

 the other with the carbon bisulphide vapour in the bomb. 

 The electrolytic gas was fired by the moving plate of 

 the chronograph, and the explosion was transmitted 

 to the fulminate, and so to the carbon bisulphide. 

 The bomb, with the detonator in position, was connected 

 with a long glass tube, having a silver bridge about one 

 metre from the bomb, and a delicate arrangement, capable 

 of being adjusted to be broken by a shock of greater or 

 less violence at the other. The other end of the tube was 

 closed by a tap, and the distance between the breaks was 

 five metres. On repeating the experiment with this 

 apparatus the decomposition was in no case propagated 

 more than about 2 - 5 metres ; the density of the deposit 

 decreasing with increasing distance from the bomb. On 

 repeating the experiment with a lead tube coiled up in a 

 water-bath at 100°, the second bridge circuit was unbroken. 

 The decomposition in the bomb itself is extremely violent, 

 and a flash of intense yellow colour can be seen in the 

 glass tube as far as the explosion proceeds. 



It appears, therefore, from these experiments, that the 

 decomposition by shock of acetylene and carbon bisulphide 

 is not propagated like the explosion-wave at a constant 

 velocity as far as the gas extends, but that the decom- 

 position set up by the fulminate dies out at a distance from 

 the detonator, depending on the nature of the gas and, 

 probably, also on the intensity of the initial shock and the 

 •cooling power of the walls. 



