The Typical Cellulose and the Cellulose Group 63 



200-300 with two to three times its weight of sodium or potas- 

 sium hydrates, cellulose is entirely resolved, the characteristic 

 products being hydrogen gas, and acetic (20-30 p.ct.) and 

 oxalic acids (30-50 p.ct). Generally the reaction takes 

 the same course as with the simpler carbohydrates, resolution 

 of the cellulose into molecules of similar constitution no doubt 

 preceding the final resolution, which appears to be an 

 exothermic or explosive reaction. 



Distinguished from the two groups of decomposition which 

 we have now considered viz. those determined (i) by hydro- 

 lytic agents, (2) by oxidising agents (under hydrolysing con- 

 ditions) are those of a more intrinsic character, determined 

 rather by the addition or withdrawal of energy, than by reaction 

 with outside molecules. 



C. RESOLUTION BY FERMENT ACTIONS. This group of 

 decompositions of cellulose is necessarily a very wide one. In 

 the * natural ' world of living organisms, of course, no structures 

 are permanent ; and although cellulose distinguishes itself by 

 relative permanence and resistance to the disintegrating actions 

 of water and oxygen, the differentiation in this respect is only a 

 question of degree, and all cellulosic structures are subject to 

 the law or necessity of redistribution. 



The directions of redistribution are chiefly three . viz. (i) In 

 the assimilating processes of the plant a cellulosic structure is 

 broken down, reabsorbed into the supply of plastic nutrient 

 material, and re-elaborated, 



(2) Structures which have ceased to play a part in the 

 general organisation of the plant are cast off and then exposed 

 as ' dead ' matter to the play of the redistributing agencies of 

 the natural world. The processes of 'decay' take various 

 forms according to the conditions to which they are exposed. 

 The humus of soils, peat, lignite, and all forms of coal present 

 various forms of the residual solid products of the decay of 



