260 DIGESTION. 



dition be subjected to the action of the gastric juice at the 

 temperature of the body, taking care to agitate it occasion- 

 ally, the edges and corners gradually become rounded, and 

 nearly the whole mass finally breaks down and is dissolved, 

 having previously become softened, so that it is easily 

 crushed between the fingers. ^ Usually, one or two points 

 appear in the mass, which are acted upon with difficulty 

 or may resist solution entirely. It is a matter of common, 

 as well as scientific observation, that hard-boiled eggs 

 are less easily digested than when they are soft-boiled or 

 raw. 



The products of the digestion of raw and of coagulated 

 albumen (albumen-peptone) are essentially the same. It is 

 probable that the entire process of digestion and absorption 

 of albumen takes place in the stomach; and if any pass 

 out at the pylorus, the quantity is exceedingly small. 



Fibrin, as distinguished from the so-called fibrin of the 

 muscular tissue, or masculine, is not a very important ar- 

 ticle of diet. The action of the gastric juice upon it is 

 more rapid and complete than upon albumen. Mialhe, who 

 has made numerous experiments on the action of the gastric 

 juice upon albuminoid substances, found the coagulated and 

 washed fibrin of the blood readily fluidified by an acidulated 

 solution of pepsin. 1 The well known action upon fibrin of 

 water slightly acidulated with hydrochloric acid has led some 

 physiologists to assume that the acid is the only principle in 

 the gastric juice necessary to the digestion of this principle ; 2 

 but careful observations on the comparative action of acidu- 

 lated water and of artificial or natural gastric juice show that 



1 MIALHE, Chimie appliquee d la Physiologic et d la Therapeutique, Paris, 

 1856, p. 115 et seq. 



2 BOITCHARDAT ET SANDRAS, Recherchcs sur la Digestion. Annales de Chimie 

 et de Physique, Paris, 1842, 3me serie, tome v., p. 478 et seq. These observers 

 attached great importance to the acid principle of the gastric juice in digestion'. 

 They supposed that it was the sole principle necessary to the digestion of fibrin 

 and some other nitrogenized substances, though they recognized the necessity 

 of the organic substance in the digestion of coagulated albumen. 



