I 7 6 



Cellulose 



numbers being the percentages of cellulose isolated by the BrAq 

 method. His results are comprised in the following table : 



An account of the applications of Fremy's method of proximate 

 analysis to the woods will be found in J. Chem. Soc. 1884, 46, 

 860 (abstracted from Urbain, Ann. Agron. 9, 529-547). 



Thus oak wood was purified by treatment with alcohol-ether 

 (losing 4 p.ct.), and afterwards with water and weak alkaline 

 solutions (losing an additional 10 p.ct). The residue, or ligno- 

 cellulose proper, is treated with cuprammonium to remove 

 cellulose ; the residue boiled with dil. HC1, and again digested with 

 cuprammonium to remove paracellulose ; the residue is vasculose. 

 Analysed in this way, the lignocelluloses of oak and poplar give 

 the following results : 



Cellulose Paracellulose Vasculose 



Oak . . . .27-05 42-90 30-05 



Poplar .... 34'io 45-95 19-95 



When this method has been employed in investigations, the 

 results should be compared with the results of the methods 

 adopted in this treatise. The reagents employed will be found to 

 be not selective in their action according to the distinctive consti- 

 tutional features of the component groups of the woods. 



Schulze investigated the resolution of the woods into 

 cellulose (insol.) and non-cellulose (sol. derivatives) by the 



