398 LIQUID PARTS OF ANIMALS. 



to revolve round the stomach in from one to three minutes. 

 The consequence of this is a thorough mixture of all the differ- 

 ent articles of food with each other. If a mouthful of some te- 

 nacious food be swallowed after digestion is considerably ad- 

 vanced, it will be seen passing the opening to the great curva- 

 ture, and in the course of one and a half or two minutes, it will 

 reappear with the general circulating contents, more or less 

 broken to pieces or divided into smaller pieces, and it very soon 

 ceases to be distinguishable. 



As the food becomes more and more changed from its crude 

 state to that of chyme, the acidity of the gastric juice is consi- 

 derably increased more so in vegetable than in animal diet 

 and the general contractile force of the muscles of the stomach is 

 augmented in every direction, giving the contained fluids an im- 

 pulse towards the pylorus. During the whole process of diges- 

 tion, the bulk of the food in the stomach is continually diminish- 

 ing ; slowly at first, but more rapidly towards the conclusion of 

 the chymification. Hence it must be passing through the pylo- 

 rus during the whole time of digestion. 



The gastric juice was extracted from the stomach of Alexis 

 St Martin in the following way : He was placed on his right 

 side. The valve within the aperture was depressed, and a caout- 

 chouc tube of the size of a large quill was introduced five or six 

 inches into the stomach. He was then turned on his left side so 

 as to make the orifice dependent The stomach was empty and 

 contracted on itself. The tube acted as a stimulant, and the 

 gastric juice began to flow first by drops, and then in an uninter- 

 rupted, and sometimes in a continuous stream. Moving the tube 

 up and down, or backwards and forwards, increased the discharge. 

 The quantity of fluid obtained was from half-an ounce to two 

 ounces troy, according to circumstances. Its extraction was at- 

 tended by that peculiar sensation at the pit of the stomach, call- 

 ed sinking, with some degree of faintness, which rendered it ne- 

 cessary to stop the operation. The juice was usually extracted 

 early in the morning when the stomach was empty and clean. 

 The following is a description of the gastric juice thus extracted, 

 as drawn up by Dr Silliman, Professor of Chemistry in Yale- 

 College. 



" The fluid, after having been kept in a closely-corked phial 

 more than three months, from April to August, and most of the 



