ON COLLOID CHEMISTRY AND ITS INDUSTRIAL APPLICATIONS. 61 
24 Scholl, Ber. 1312 (1911). 
25 Ermen, Journ. Soc. Dyers and Cols. 26, 266 (1910) ; 2'°7,(1911). 
26 Harrison, Journ. Soc. Dyers and Cols. 28, 359 (1912). 132 
Cellulose Peroxide. 
27 Cross & Bevan, Zeit. angew. Chem. 19, 2101 (1906). 
*8 Cross, Bevan & Briggs, ibid., 20, 570 (1907). 
29 Ditz, Chem. Ziet, 31, 833, 844, 857 (1907). 
90 Heinke, ibid., 31, 974 (1907). 
31 Zimmermann, Ziet. fur angew. Chem. 20, 1286 (1907). 
% Ditz, Jowrn. prakt. Chem. 78, 343 (1908). 
33 Grandmougin, Chem. Zeit., 32, 242 (1908). 
Cellulose Ozonide. 
34 Dorée, Trans. Chem. Soc. 101, 497 (1912). 
Action of Light on Cellulose. 
% Hartley, Proc. Roy. Soc. B '78, 385; 80, 376. 
36 Hartley, Trans. Chem. Soc. 68, 243 (1893). 
37 Harrison, Journ. Dyers and Cols. 28, 225 (1912). 
38 Dorée & Dyer, ibid., 38, 19 (1917). 
Cellulose Nitrates. 
When cellulose is treated with a mixture of sulphuric and nitric 
acids, esters are formed containing nitrogen in quantities varying 
with the conditions of treatment.’~*7 911121425 Many authors®§® 
have attempted to classify the products, according to degree of 
nitration, into nitrates of definite molecular composition but there 
seems to be no break in the curve representing the amount of nitro- 
gen introduced by different concentrations of acid.1!!17 The sug- 
gestion has been made’ that nitrocelluloses are adsorption compounds 
but this view does not appear to have been substantiated.’ There 
is little doubt that true esters are formed, but as the cellulose is solid 
during treatment, the reaction must take place from the exposed 
surfaces, whether external or within the porous structure of the fibre, 
and the degree of nitration must be dependent on the colloidal state 
of the fibre substance. 
The viscosity of solutions of nitrocellulose! ¥ 18 19 20?! vary with 
the conditions of preparation. A nitrocellulose after solution and 
reprecipitation has been shown to give a less viscous solution than 
one directly dissolved.!* Similar changes have been observed with 
rubber solutions. 
The behaviour of nitrated cotton towards polarised light has been 
investigated by several authors * 1°71”? and many interesting points 
brought forward. 
(G) Cellulose Nitrates. 
1 Cross & Bevan, Cellulose, p. 38. 
? Schwalbe. Die Cellulose, p. 270. 
3 Schonbein, Camp. Rend. 23, 678 (1846). 
* Otto. ibid., 23, 807 (1846). 
> Crum, Proc. Phil. Soe. Glasgow, 183 (1847). 
6 Eder, Ber., 13, 169 (1880). 
7 Knecht, Journ. Soe. Dyers § Cols., 12, 89 (1891). 
8 Veielle, Comp. Rend., 95, 132 (1883). 
9 Liebschutz, Mon. Sci., p. 119 (1891). 
1 Vignon, Comp. Rend., 126 (1898). 
