CHAPTER XIV. 



CHEMICAL CHARACTERISTICS OF THE 

 CORDAGE FIBRES. 



FLAX fibre when treated with iodine and sulphuric acid is 

 coloured blue, whereas jute when treated in the same bath is 

 coloured yellow, and hemp green. The flax fibre consists of 

 pure cellulose, and is not lignified. It swells by treatment with 

 Schweitzer's reagent, but, unlike cotton, does not completely 

 dissolve in it. 



The following analysis shows the approximate composition 



of the flax fibre of commerce : 



Per cent. 



Hydroscopic water 9-7 



Aqueous extract 4*8 



Fat and wax 2-4 



Cellulose 77-0 



Ash (mineral matter) ... ... 1*0 



Intercellular matter 5-1 



Thus the ordinary commercial flax fibre contains about 5 per 

 cent, less cellulose than cotton, the difference being made up 

 of impurities present in the form of intercellular matter and 

 specific bodies such as a wax-like substance which may be ex- 

 tracted from the fibre by means of benzene or ether. Its 

 melting point is 143 F., and its specific gravity 0-9 at 60 F. 

 According to Hoffmeister this wax consists of about 8i per 



