Compound Celluloses ill 



authors' results given in the text, the numbers must be calculated 

 to dry substance (i.e. multiplied by i'i). 



The authors have not isolated pectic acid from the fibre- 

 substance proper ; but jute * cuttings ' often contain a considerable 

 quantity, 



Composition. The inorganic constituents amount to 

 from 0-8-2-0 p.ct, and are obtained, on burning the fibre, 

 as a brownish-coloured ash, of which the preponderating 

 constituents are silica (35 p.ct), lime (CaO 15 p.ct.), and 

 phosphoric acid (P 2 O 5 n p.ct.). Manganese is usually present 

 in small quantity (Mn 3 O 4 075 p.ct.). 



The organic portion, or fibre substance proper, varies some- 

 what in composition, the subjoined numbers representing the 

 mean range of variations : 



C 46 -0-47-0 p.ct. 



H . . . . 6-3- 5'8 



In dealing with the jute fibre substance in contradistinction to 

 the jute fibre, the results are referred to the substance taken as dry 

 (100) and when the result would be seriously influenced, as ash- 

 free. 



For ' statistical ' purposes, therefore, the fibre-substance may 

 be represented by the empirical formula C 12 H 18 O 9 . There 

 is plenty of evidence for the view that lignification is an in- 

 trinsic process of chemical change of cellulose, and it might 

 therefore be inferred that the process is one of dehydration : 

 C 12 H 20 Oio H 2 O = C 12 H 18 O 9 . 



As an illustration of the superficial meaning of such 

 numerical relationships, we may cite here the results obtained 

 by A. Pears in cultivating the jute plant under the more 

 artificial conditions of growth in a ' hot house ' in this country. 

 A normal growth of the plant was secured, in the sense 

 that the seed saved gave a satisfactorily high proportion of 

 germination in the second year of cultivation, and from both 

 cultivations good specimens of the bast fibre, were separated in 



