ON COLLOID CHEMISTRY AND ITS INDUSTRIAL APPLICATIONS, 97 
2 8. Judd Lewis, Zbid. 34, 167, (1918). 
33. W. L. Balls, Journ. Soc. Arts. p. 389, (1918). 
340. F. Cross, Jowrn. Soc. Dyers § Cols. 34, 215, 247, (1918). 
sW Harrison, Ibid. 34, 218, (1918). 
36 Knecht & Hall, Zoid. 34, 220, (1918). 
Compound Celluloses : 
37 Cross & Bevan, Cellulose, pp. 89-232. 
88 Schwalbe, Die Cellulose, pp. 366-483. 
89 Stocks, First Report on Colloid Chemistry, pp. 58-64. 
Animal Celluloses : 
40 Worden, Nitrocellulose Industry, p. 1. 
41 Trvine, Trans. Chem. Soc., 95, 564, (1909). 
Cellulose Solutions. 
The so-called solutions of cellulose are really colloidal solutions. 
The best known solvents are Schweitzer’s reagent, ° 18 2! zine chloride 
solution and sulphuric acid. Numerous other solvents have been 
found in recent years.’ Recently, ® it has been stated that cellulose 
can be dissolved in solutions of most salts when heated under 
pressure. 
Regarding the solution of cellulose in ammoniacal copper solution 
Cramer * came to the conclusion from osmotic measurements that it 
was a true solution. Erdmann, ! on the other hand, considered it 
to be a very highly hydrated cel. Cross & Bevan it’ expressed the 
view that the copper compound combined with the cellulose to form 
a colloid double salt. 8° The dialysis of these copper solutions has 
been studied by Grumaux ” who came to the conclusion that it was 
the non-dialysable portion of the solution of copper hydrate in 
ammonia which acted as a solvent for cellulose. 
It is important to note that cuprammonium hydroxide is not so 
strong an alkali as caustic soda. ¥ 
The solution of cellulose in ammoniacal copper solution has been 
stated to be optically active 1-! a view which does not appear to be 
substantiated. 16 The solution of cellulose in hydrochloric acid is 
optically inactive. 7 
(C) Cellulose Solutions. 
1 Compare B.! 
? Compare B.? 
3 Compare B.3 
4 Czapek, Biochemie der Pflanzen, Jena, 1905. 
5 Abderhalden, Biochem Handlewihkon, Berlin, 1911 (11) Cellulose. 
6 Schweitzer, Tourn. Siir prakt. Chem. 42, 109, 3441 (1857). 
7 Deming, Journ. Amer. Chem. Soc. ; a5, LOLS (1911). 
8 Weimarn, Koll Zeit, 11, 41 (1912). 
9 Cramer, Jowrn. fiir ‘prakt. Chem., 93, 1 (1858). 
10 Erdmann (Compare B}, p. 11). 
11 Cross & Bevan, Textbook of Papermaking, p. 8. 
12 Grumaux, Comp. Rend., 98, 1885. 
18 A. M. Dawson, Trans. Chem. Soc. 89, 1666 (1906) ; 95, 370 (1909). 
14 Levallois, Bull Soc. Chem. (2) 48, 83, 616 (1885). 
15 Levallois, Comp. Rend., 98, 372, 732 (1884) ; 99, 431, 1027 (1884). 
16 Bechamp, bid. 99, 1027, 1122 (1884) ; 100, 279, 368 (1885). 
17 Willstatter & Zechmeister, Ber., 46, 2401 (1912). 
18 Schlossherger, Jowrn. fiir prakt. Chem. 93, 373 (1858). 
19 Lehner, Zeit. fiir angew. Chem., 19, 1584 (1906). 
20 Mulder, Jahr. der Chem., 566 (1863). 
2 Haller, Zeit. fiir Farben Ind. 6, 126 (1907). 
