ANIMAL FUNCTIONS. 



329. Physiologists have contrived to extract the gastric 

 juice from the stomachs of various animals by means of 

 a sponge, which being introduced in the dry state is 

 withdrawn filled with the fluid, which being squeezed out, 

 the operation is repeated until a quantity for experi- 

 ment is obtained. In a case described hereafter, this 

 was unnecessary, there being an orifice in the human 

 stomach through which the juice was taken. The fluid 

 thus obtained is destitute of any sensible properties by 

 which its power as a solvent can be accounted for. It fs 

 a clear transparent liquor, with a little taste or smell. But 

 its action on various substances was found to be very 

 peculiar and striking. Spallanzani, formerly the most 

 celebrated experimenter on this subject, found, that 

 when boiled meat was exposed to the action of this agent, 

 from the human stomach, that it lost its fibrous texture, 

 and was finally reduced to a pultaceous mass, in imitation 

 of the actual process of digestion. 



330. It was found abo, that this juice from the stomachs 

 of animals of different races, produced different effects, 

 thus proving what indeed had ever been proved by the 

 animals themselves, that the stomachs of eagles and other 

 carnivorous animals cannot digest vegetables, nor can the 

 sheep and ox digest meat. That from the stomach of 

 omniverous man, however, was found to dissolve both ve- 

 getable and animal matter with equal facility. 



332. Chemical effects of the Gastric Juice. Nearly all 

 physiologists of the present day, are agreed that the 

 change produced by the action of the gastric fluid, on the 

 aliment of the stomach, must be referred to chemical prin- 

 ciples, and yet nothing can be detected in the juice itself 

 by chemical analysis, which in any degree accounts for 

 the phenomena produced. 



332. The coagulating effect of the gastric juice is its 

 most obvious property. By this property, fluid substances, 

 whether animal or vegetable, which are capable of coag- 

 ulation, are rendered nearly solid. Thus the white of 



When the gastric juice is extracted from the stomach and mixed with 

 food, what erfect is produced? What was proved with respect to the 

 capacity of different animals lo digest the same kind of food? On what 

 principle do physiologists account for the effects of the gastric juice ? 



