154 Cellulose 



Chorley and Ramsay, who obtained the following results 

 (J. Soc. Chem. Ind. n). 



Weight of fibre .71 grms. 73 grms. 



P.ct. P.ct. 



Charcoal . . . . .2871 32*87 



Total distillate . . 5770 43'iS 



Carbonic anhydride . 12 -33 



Other gases (and loss) ... H'65 



100-00 



Volume of gas .... 3,000 c.c. 2,500 c.c 

 per 100 grms. . . 4,220 3,420 



Composition of Products p,ct. 



f Carbon monoxide . . 



Gas . \ Oxygen .... 



I Residual gas . . . 



P.ct. fibre 



|- Tar ..... 1478 6-85 



Distillate -I Acetic acid .... 0*40 1-40 



I Methyl alcohol . . . 10-08 



The chief features to be noted in the products are the low 

 yields of charcoal (compare p. 69) and acetic acid, and the 

 high yields of carbonic oxide and methyl spirit. The thermal 

 features of the decomposition are remarkable : heated gradually 

 to 320 the temperatures within the distilling flask and external 

 to it follow the ordinary course ; but at 320 (external) the 

 temperature within the flask rushes up to 375, the change 

 being marked by a much increased evolution of gas. 



The destruction of a complex substance such as the ligno- 

 cellulose, by heat, involves a highly complicated web of reac- 

 tions, which it would be impossible to disentangle in detail 

 and in such a way as to throw light on the fate of particular 

 groups. In the main there are, of course, the two opposing 

 factors at work dissociation, giving products of lesser, to those 

 of the least molecular weight (gases) ; and condensation, giving 



