Composition and Nutritive Value of Cotton-cake. 11 



supplying cattle with decorticated cotton-cake ; and as it is, more- 

 over, cheaper than the thin cake, its use for feeding purposes is 

 not only more convenient, but likewise more economic, than that 

 of thin cotton-cake. 



There is, however, a certain degree of danger in buying a 

 powder, for rubbish of various sorts may be mixed with the 

 meal by unprincipled dealers. But, on the other hand, the 

 respectability of the dealer and chemical analysis afford the 

 means of preventing this species of fraud. 



As decorticated cotton-cake is likely to be extensively used 

 for feeding purposes, I have thought it advisable to submit the 

 mineral constituents which it furnishes on burning to a detailed 

 examination. 



The following results were obtained in my laboratory by my 

 friend and pupil Mr. Gardner, of Shrewsbury, on analysing the 

 ash prepared from several samples of decorticated cake : 



Average Composition of the Ash of Decorticated Cotton-cake. 



Potash 39-045 



Soda . . . . none 



Chloride of sodium none 



Lime 3'750 



Magnesia 13'500 



Oxide of iron 1-530 



Phosphoric acid 39'649 



Sulphuric acid '930 



Carbonic acid -362 



Soluble silica 3-252 



Insoluble silicious matter (sand) .. .. 17*706 



99-724 



Like other oily seeds, cotton-seed contains, it will be seen, a 

 considerable quantity of phosphate of magnesia. In addition to 

 these compounds it contains phosphate of lime and phosphate of 

 potash, and other salts of potash. 



The proportion of phosphoric acid in cotton-cake ash is very 

 large, and that of potash likewise is considerable. Soda does 

 not enter into the composition of the ash. For the purpose of 

 supplying animals with bone-materials, it is a very valuable kind 

 of food. 



CONCLUSION. 



The principal points of interest, in reference to cotton-cake, 

 are collected together in the following short summary : 



1. The best cotton-cake is richer in oil and albuminous (flesh- 

 forming) compounds than linseed-cake, but contains less mucilage 

 and other respiratory constituents. 



