USES OF THE BUTTER, &c. 51 



erties ; insomuch, that certain plants, such as peas, 

 beans, and lentils, are capable of producing the same 

 substance which is formed from the blood of the mother, 

 and employed in yielding the blood of the young ani- 

 mal. (9) 



The young animal, therefore, receives, in the form 

 of caseine, which is distinguished from fibrine and al- 

 bumen by its great solubility, and by not coagulating 

 when heated, the chief constituent of the mother's 

 blood. To convert caseine into blood no foreign sub- 

 stance is required, and in the conversion of the mother's 

 blood into caseine, no elements of the constituents of 

 the blood have been separated. When chemically ex- 

 amined, caseine is found to contain a much larger pro- 

 portion of the earth of bones than blood does, and that 

 in a very soluble form, capable of reaching every part 

 of the body. Thus, even in the earliest period of its 

 life, the development of the organs, in which vitality 

 resides, is, in the carnivorous animal, dependent on the 

 supply of a substance, identical in organic composition 

 with the chief constituents of its blood. 



What, then, is the use of the butter and the sugar of 

 milk ? How does it happen that these substances are 

 indispensable to life ? 



Butter and sugar of milk contain no fixed bases, no 

 soda or potash. Sugar of milk has a composition 

 closely allied to that of the other kinds of sugar, of 

 starch, and of gum ; all of them contain carbon and the 

 elements of water, the latter precisely in the proportion 

 to form water. 



