128 OXIDES WITHOUT AZOTE, NOT OILY. 

 SECTION II. OF OONIN. 



This name (from <wov, an egg,) has been given to a peculiar 

 principle which M. Couerbe extracted from the albumen of an 

 egg in the year 1829, and to which he gave at first the name of 

 albuminin, but afterwards changed for oonin* 



M. Couerbe left a concentrated solution of albumen from an egg 

 in water, in a temperature varying from 32 to 18. The solu- 

 tion became thick without congealing, and in about a month de- 

 posited a membranous net-work, which was pretty abundant. 



This membranous matter is solid, white, translucent, com- 

 posed of membranes, tasteless, and without smell. It was easily 

 reduced to powder. 



When heated in a glass tube, shut at one end, it is decomposed 

 without melting, and yields no ammonia. During its calcination 

 it swells, and leaves a bulky charcoal difficult to burn. When 

 decomposed by oxide of copper and heat, it gives nothing but 

 water and carbonic acid gas. 



It is insoluble in water, though it is softened by that liquid. 

 In boiling water it swells without dissolving, and assumes the ap- 

 pearance of insoluble mucor. 



Alcohol, ether, and acetic acid have no action on it whatever, 

 either cold or hot. It swells slightly in concentrated sulphuric 

 acid while cold ; but if we apply a gentle heat, the oonin is ra- 

 pidly charred, and gives out an agreeable smell. When water 

 is added, the charred matter precipitates, leaving a colourless di- 

 lute acid. Cold nitric acid acts but feebly on oonin ; but when 

 heat is applied, it dissolves it with the evolution of deutoxide of 

 azote. The best solvent of oonin is hot muriatic acid. The so- 

 lution is colourless, and no precipitate falls when it cools ; but if 

 we add water, the liquid becomes muddy, and a white precipi- 

 tate falls in the state of a very fine powder. 



Alcoholic solution of potash dissolves it with the assistance of 

 a little heat When the liquid cools no precipitate appears. If 

 we saturate the alkali with muriatic acid, the mixture becomes 

 muddy ; but no precipitate falls during twenty-four hours. 

 These experiments of Couerbe were repeated and confirmed by 

 MM. Soubeiran, and Henri, Jun.f 



Ann. de China, et de Phys. xli. 323. 

 \ Jour, de Pharm. xv. 495, and xix. 299. 



