412 



A TEXTBOOK OF PHYSIOLOGY 



churn up the food when the pyloric orifice is closed, and pass it on to 

 the duodenum when the orifice is open. 



These churning movements are the first movements noticed when 

 an animal is examined under X rays after receiving a good 



A Hours B 



FIG. 204. To SHOW EFFECT OF CONSISTENCY OF FOOD UPON THE RATE OF LEAVING 

 THE STOMACH. (Cannon.) 



A, Light continuous line = potato of standard consistency; heavy continuous line = 

 potato of thick doughy consistency; dash line = thin gruelly consistency. 

 B, heavy line=lean beef of standard consistency; light line=lean beef of thin 

 gruelly consistency. 



meal. After a short time, an annular constriction appears at the 

 vestibule, and passes slowly over the rest of the pylorus, being followed 

 by regular waves arising in the same region. Then a little later (two 



FIG. 205. 



The continuous line shows the rate of 

 disappearance from the stomach of a 

 carbohydrate meal (biscuits, rice, pota- 

 toes) moistened with water; the dotted 

 line of a similar meal moistened with 

 1 per cent. NaHCO :! . There is marked 

 retardation of the latter. (Cannon.) 



Hours J 1 2 

 FIG. 206. 



The continuous line shows the rate of 

 disappearance of a meal of protein 

 (fibrin, fowl, lean beef); the dotted line 

 that of same meal fed as acid protein. 

 (Cannon.) 



to three minutes) the contractions which arise from the middle of the 

 body make their appearance, the amount of contraction becoming 

 much more marked when the vestibule is passed. These peristaltic 



