THE CARBOHYDRATES 



27 



Cotton is obtained, in the raw state after separation from 

 the seeds, as cotton wool, and in the form of various manu- 

 factured products, e.g. spun thread, woven cloth, Swedish filter 

 .paper, etc. 



Under the microscope it presents the appearance of a 

 flattened ribbon with a central longitudinal canal running 

 through it. 



FIG. 2. Cotton cellulose fibres X 250. 



When freed from adventitious matter it is colourless, 

 tasteless, odourless, and quite insoluble in water. The 

 percentage composition carbon 44-4, hydrogen 6-2, oxygen 

 49'4 corresponds to the simplest formula, C 6 H 10 O 5 . It is 

 not at all volatile, but is decomposed charred or burned on 

 heating. 



Chemically, it is very inert. It offers great resistance to 

 hydrolytic treatment, oxidation, and other modes of attack. 

 Dilute mineral acids, and hot concentrated organic acids, 



