

ALBUMEN. 1 3 



among them are albumen, fibrin, casein, syntonin, myosin, 

 and globulin. 



Albumen exists in most of the tissues of the body, but 

 especially in the nervous, in the lymph, chyle, and blood, 

 and in many morbid fluids, as the serous secretions of 

 dropsy, pus, and others. In the human body it is most 

 abundant, and most nearly pure, in the serum, of the blood. 

 In all the forms in -which it naturally occurs, it is com- 

 bined with about six per cent, of fatty matter, phosphate 

 of lime, chloride of sodium, and other saline substances. 

 Its most- characteristic property is, that both in solution 

 and in the half-solid state in which it exists in white-of- 

 egg, it is coagulated by heat, and in thus becoming solid, 

 becomes insoluble in water. The temperature required 

 for the coagulation of albumen is the higher the less 

 the proportion of albumen in the solution submitted 

 to heat. Serum and such strong solutions will begin to 

 coagulate at from 150 to I/O , and these, when the 

 heat is maintained, become almost solid and opaque. 

 But weak solutions require a much higher temperature, 

 even that of boiling, for their coagulation, and either only 

 become milky or opaline, or produced flocculi which are 

 precipitated. 



Albumen, in the state in which it naturally occurs, ap- 

 pears to be but little soluble in pure water, but is soluble 

 in water containing a small proportion of alkali. In such 

 solutions it is probably combined chemically with the 

 alkali ; it is precipitated from them by alcohol, nitric, and 

 other mineral acids, by ferrocyanide of potassium (if before 

 or after adding it the alkali combined with the albumen be 

 neutralised), by bichloride of mercury, acetate of lead, and 

 most metallic salts. 



Coagulated albumen, i.e., albumen made solid with heat, 

 is soluble in solutions of caustic alkali, and in acetic acid 

 if it be long digested or boiled with it. With the .aid of 

 heat, also, strong hydrochloric acid dissolves albumen pre- 



