44 Cellulose 



under a pressure nearly equal to the atmospheric as in a ' miss 

 fire ' the percentage composition (by vol.) of the gases is 

 NO ...... 247 



CO 4i'9 



C0 a 18-4 



H 7'9 



N 5'8 



CH 4 . . . . . . 13 



lOO'O 



(See Karolyi, Phil. Mag. 1863, 266; also Abel, Phil. Trans. 

 1866, 269 ; 1867, 181.) 



INDUSTRIAL USES OF THE CELLULOSE NITRATES. These 

 products find a number of highly important uses both for de- 

 structive and constructive purposes. As far as these uses in- 

 volve, or are based upon, essential properties of the products, 

 they may be briefly noticed here. 



EXPLOSIVES. The products of which gun cotton or other 

 nitrated celluloses is the essential constituent are of three 

 main classes : (i ) containing the nitrates only ; (2) the nitrates in 

 admixture with inorganic salts containing oxygen * available ' 

 for combustion, or aromatic nitro-derivatives, &c. ; (3) the 

 nitrates in admixture with, or solution in, nitro-glycerin (blast- 

 ing gelatine, ballistite, or cordite). An account of these 

 modern explosives, with determinations of their constants of 

 explosion, will be found in a paper by Macnab and Ristori, 

 Proc. R. S. 1894, 56. 



CELLULOID, XYLONITE, &c. The lower nitrates are worked 

 up with solvents of a special character (acetone, camphor, &c.), 

 with or without admixture of various substances, into plastic 

 masses, which are then cut and moulded into articles of most 

 varied form and use. 



COLLODION, COLLODION VARNISHES, COLLODION FILMS. 

 The lower nitrates, dissolved in ether-alcohol or other solvents 

 (amyl acetate and benzene, &c.), form transparent solutions, 



