CASEIK. 185 



Nor does it dissolve in cold nitric acid ; but it is easily soluble 

 in that acid when assisted by heat. Moist albumen dissolves in 

 nitric acid at the common temperature, and oxalic acid is formed. 

 It is not acted on by muriatic acid unless heat be applied when 

 it is dissolved. Moist albumen dissolves in it at the ordinary 

 temperature of the atmosphere. By phosphoric acid and heat it 

 is charred and decomposed. 



When dissolved in concentrated acetic acid, the solution has a 

 fatty feel, which Mulder considers as a remarkable distinguish- 

 ing character. When prussiate of potash is dropt into this so- 

 lution a beautiful green precipitate falls, which is insoluble in wa- 

 ter. By this property a minute quantity of this albumen may 

 be discovered. 



It dissolves in potash, soda, and ammonia, and is precipitated 

 again by acids. If we add acetic acid to the potash solution it 

 will not blacken silver. It is insoluble in carbonated potash, so- 

 da, or ammonia.* 



According to Mulder's analysis it is composed of, 

 Carbon, . 54-005 

 Hydrogen, . 7-270 

 Azote, . 15*456 



Oxygen, . 23-269 



100-OOOf 



These numbers come sufficiently near the various analyses of 

 albumen from blood and eggs to show that all these substances 

 are isomeric. 



SECTION III. OF CASEIN. 



Milk is the well known liquid secreted by the females of the 

 whole class of mammalia to nourish their new-born offspring. 

 The milk of the cow has been used as a common article of food 

 from the earliest ages. Hence its appearance, its taste, and its 

 nourishing properties are known to every person. 



Milk underwent a chemical examination from Neumann. He 

 ascertained the quantity of water which it contained, and Dr 

 Lewis showed that its boiling point was the same as that of wa- 

 ter ; that it is coagulated by acids and also by alkalies. The co- 



* Poggendorf s Amialen, xxxvii. 608. f Ibid. xl. 270. 



