AND ABSORPTION 33 



by a strong contraction ring from the fundus ; the 

 latter being distended and globular whilst the pyloric 

 antrum is tubular. Formalin-hardened bodies often 

 show a similar disposition, but, as Hertz has proved, 

 this separation into two portions does not always 

 take place. The cardiac end acts as a reservoir, 

 while the muscle of the pyloric end is principally 

 concerned with driving the food through the 

 pylorus. 



The general trend of gastric movements is as follows. 

 Soon after food is taken, the muscular wall of the 

 stomach is thrown into contractions, starting from 

 the cardiac end, and the contents are hurled repeatedly 

 from left to right against the tight-closed pylorus. 

 At length, when the fluid mass impinging on it is 

 thoroughly impregnated with acid, the sphincter 

 yields momentarily, and allows a little to pass through. 

 This process continues until the stomach is empty. 

 Solid pellets, such as bismuth pills, are not readily 

 allowed to escape, and a bread mixture, which 

 normally began to pass into the duodenum fifteen 

 minutes after eating, was delayed for over forty 

 minutes when the pills were given with it. 



When the stomach is empty the pylorus is relaxed, 

 but quite energetic gastric peristalsis continues to 

 take place. It is probable that these movements give 

 rise to the gastric sensation which we call hunger 

 (Hertz). Bile and duodenal contents readily pass in 

 and out again without exciting any discomfort. 



It is interesting to note that Cannon and Murphy 

 have found, if the jejunum is cut across near the 

 upper end and then sutured, that the pylorus remains 



3 



