The Typical Cellulose and the Cellulose Group 83 



dextrose) in only small proportions. (Lindsey and Tollens, Lieb. 

 Ann. 267, 370.) 



Investigation has stopped short at this negative result. It would 

 be of interest, therefore, to isolate the products formed in the re- 

 action with the concentrated sulphuric acid, so as to characterise 

 them, at least generally. Until this is done, or some other method 

 proximate resolution is worked out in detail, we can only say that 

 the constitution of these celluloses is in some important feature 

 radically different from that of the typical cellulose. 



An account of recent investigations of these * celluloses ' will 

 be found in Berl. Ber. 1893, and a more special treatment of 

 the subject, ibid. 1894, and J. Chem. Soc. 1894 (C. Smith). 



Of this group of the natural oxycelluloses the following 

 have been more particularly investigated : 



(i) Celluloses from woods and lignified tissues generally. 

 Lignified tissues are made up of compound celluloses, to be 

 subsequently described (see Lignocelluloses, p. 91), from which 

 the celluloses may be isolated by a number of treatments, all 

 depending upon the relative reactivity of the so-called ' non- 

 cellulose ' constituents, which in combination with the celluloses 

 make up the compound cellulose, lignocellulose or wood sub- 

 stance. These non-cellulose constituents are readily attacked 

 and converted into soluble derivatives ; and there are various 

 industrial processes for preparing celluloses (paper pulp) from 

 raw materials of this class, depending upon the direct conversion 

 of the former into such soluble compounds. The isolated 

 celluloses show the following general characteristics (Berl. 

 Ber. 27, 1061) : 



Elementary composition { ^.g^.'* ^ Yidd f fur ~ 



fural, by solution and hydrolysis (HC1), 2-6 p.ct. Reactions 

 with phenylhydrazine salts and magenta-sulphurous acid, indi- 

 cating the presence of active CO groups. These celluloses 

 are necessarily less resistant to oxidation and hydrolysis, but 



G2 



