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CHAPTEE VII. 



GUN-COTTON AND NITROCELLULOSES. 



1. HISTORICAL. 



1. IN 1846 Schonbein proposed to replace service powder by a 

 new substance, the composition of which he kept a secret. This 

 was gun-cotton, the discovery of which is the starting-point of 

 the works since accomplished with the new explosive substances. 

 In 1832 Braconnot and Pelouze had already made known some 

 similar nitric compounds. 



Numerous experiments carried out up till 1854 led to gun- 

 cotton being regarded as more powerful for equal weights than 

 black gunpowder, that it possessed shattering properties which 

 hardly admitted of its continued use in firearms. Soon, terrible 

 explosions and accidents in powder factories 1 gave evidence of 

 the existence of spontaneous decompositions, which put a stop 

 to its manufacture almost everywhere; nevertheless, experi- 

 ments were still carried out in Austria, under the direction of 

 Lenck, until the occurrence of a fresh explosion in a magazine 

 at Simmering in 1862. Another explosion occurred in 1865 at 

 Wiener-Neustadt. 



2. In England, however, Abel succeeded in almost entirely 

 removing risks by a very careful process of manufacture, namely, 

 by reducing the cotton to pulp, which enabled it to be more 

 completely washed, and finally, by the compression of the cotton 

 (1865) by hydraulic presses. 



Compressed gun-cotton thus came into use. Brown discovered 

 in 1868 that it could be detonated by means of mercury 

 fulminate. 



The explosion which happened in 1871 in the Stowmarket 

 factory, and in which twenty-four persons perished, was at- 

 tributed, rightly or wrongly, to imperfect supervision, and the 

 manufacture of compressed gun-cotton is still carried out in 

 England. It has been carried out also in France for some time 

 at the " Moulin Blanc " factory. 



1 Bouchet and Vincennes, 1847. 



