198 Cellulose 



C, 48-4 ; H, 6-3 p.ct. From these results, together with general 

 observations on the chemical behaviour of the substance, it 

 was concluded that it is a homogeneous compound, having the 

 empirical formula C 30 H 46 O2i. Erdmann further concluded 

 that this compound is resolved by hydrolysis with dilute 

 acids into glucose (soluble) and a residue C 2 6Ho 6 O n , which 

 he terms lignose, and the original compound therefore 

 glycolignosc. Lignose was further found to yield, on fusion 

 with potassium hydrate, pyrocatechol and protocatechuic 

 acid. 



These results, or rather the interpretation of them, is incon- 

 sistent in many respects with the results of subsequent investi- 

 gations. The experimental facts, however, remain ; and the 

 researches are worthy of notice, as one of the earliest attempts 

 to elucidate the constitution of the lignocelluloses as a definite 

 chemical problem. 



The ' sulphite pulp ' process would appear to offer a much 

 more promising field of investigation, since it not only deter- 

 mines a satisfactorily sharp separation of cellulose (pulp) from 

 non-cellulose (soluble sulphonated derivatives), but with the 

 minimum of chemical modification of either group. Notwith- 

 standing these specific advantages of the process, considered 

 as a method of proximate analysis, and numerous investigations 

 of the soluble by-products (' sulphite liquor '), the constitution 

 of the latter, and therefore of the original lignocellulose, still has 

 to be expressed in very general terms. The most important 

 contribution to the subject is that of Lindsey and Tollens 

 (Annalen, 267, 341), of which the following is a brief account. 

 The solution used in these researches was that resulting from 

 the ' Mitscherlich process,' which consists in a prolonged diges- 

 tion of the wood after subjection to a preliminary mechanical 

 disintegration with a solution of calcium bisulphite. The 

 solution is usually prepared to contain CaO 1*35 p.ct, SO 2 



