162 USES OF COMMON SALT 



by animals of different classes, to support tlie vital 

 processes, are singularly unequal. 



If we suppose, that a given amount of blood, 

 considered as a compound of soda, passes, in the 

 body of a carnivorous animal, in consequence of the 

 change of matter, into a new compound of soda, 

 namely, the bile, we must assume, that in the nor- 

 mal condition of health, the proportion of soda in 

 the blood is amply sufficient to form bile with the 

 products of transformation. The soda which has 

 been used in the vital processes, and any excess of 

 soda, must be expelled in the form of a salt, after 

 being separated from the blood by the kidneys. 



Now, if it be true, that, in the body of an herbivo- 

 rous animal, a much larger quantity of bile is pro- 

 duced than corresponds to the amount of blood 

 formed or transformed in the vital processes ; if the 

 greater part of the bile, in this case, proceeds from 

 the non-azotised constituents of the food, then the 

 soda of the blood which has been formed into or- 

 ganised tissue (assimilated or metamorphosed) can- 

 not possibly suffice for the supply of the daily secre- 

 tion of bile. The soda, therefore, of the bile of the 

 herbivora must be supplied directly in the food ; 

 their organism must possess the power of applying 

 directly to the formation of bile all the com^^ounds 

 of soda present in the food, and decomposable by 

 the organic process. All the soda of the animal 

 body obviously proceeds from the food ; but the 

 food of the carnivora contains, at most, only the 



