154 USES OF COMMON SALT. 



matter, into a new compound of soda, namely, the 

 bile, we must assume, that in the normal condition of 

 health, the proportion of soda in the blood is amply 

 sufficient to form bile with the products of transforma- 

 tion. The soda which has been used in the vital pro- 

 cesses, 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 produced 

 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-azotized 

 constituents of the food, then the soda of the blood 

 which has been formed into organized tissue (assimilated 

 or metamorphosed) cannot possibly suffice for the sup- 

 ply of the daily secretion 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- 

 pounds 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 amount of 

 soda necessary to the formation of blood ; and in most 

 cases, among animals of this class, we may assume that 

 only as much soda as corresponds to the proportion 

 employed to form the blood, is expelled in the urine. 



When the carnivora obtain in their food as much 

 soda as suffices for the production of their blood, an 



