Compound Celluloses 193 



lose), it should be formed correlatively with the furfural-yielding 

 compounds ; and the quantitative relations of the two certainly 

 confirm this view. Thus the hypothetical decomposition may 

 be formulated as under : 



2C 6 H 12 O 6 = 2C 5 H 10 5 + C 2 H 4 O 2 , 

 2x150 60 



and the pentosans of wood represent in effect a percentage 

 approximately five times that of the acetic acid obtainable 

 by simple hydrolysis. 



In the jute fibre also, the smaller proportion of the fur- 

 fural-yielding constituents is associated with a similar smaller 

 proportion of the acetic residue. The formation of both 

 therefore increases, paripassu, with age, which is in accordance 

 with the view of a common origin. 



(2) The celluloses, and the 'carbohydrates' generally, are 

 susceptible of the ' acetic condensation.' The normal cellu- 

 loses, however, require the application of drastic treatments, 

 e.g. fusion with alkaline hydrates or warming with concentrated 

 sulphuric acid, both of which treatments are of an oxidising 

 character. The oxy celluloses , on the other hand notably the 

 straw celluloses give a considerable yield of acetic acid 

 (together with furfural) on long boiling with 10 p.ct. sulphuric 

 acid. The maximum yield is obtained by dissolving the oxy- 

 cellulose in the concentrated acid in the cold, diluting and dis- 

 tilling. In this way the authors have obtained a yield of 

 9-10 p.ct. of the acid, calculated on the oxycellulose. 



These observations confirm the view that lignification is a 

 process of transformation taking place in oxidised celluloses, 

 or oxycelluloses, and following as a secondary result of the dis- 

 turbance of equilibrium set up by the oxidation. 



(3) In addition to acetic residues converted by hydrolysis 

 into acetic acid there appears to be a CO.CH 2 nucleus, a 

 dehydracetic residue, which is the source of the increased 



o 



