452 



DIGESTION 



ing the animal with food that has been impregnated with bismuth sub- 

 nitrate, then exposing him to the x-ray and either taking instantaneous 

 photographs of the shadoAvs or observing them by means of a fluorescent 

 screen. The descriptions of the original observations made by Cannon 



Fig. 154. Schematic outline of the stomach. At C is the cardia; F, fundus; I A, incisura an- 

 gularis; B, body; PC, pyloric canal; P, pylorus. (From Cannon.) 



on the stomach of the cat have been so little modified by observations 

 on man that we may take them as a convenient type. In the accompany- 

 ing figure (Fig. 156) the outline of the shadow cast by the stomach is 

 shown at intervals of an hour each during digestion. Soon after the 



Fig. 155. Diagrams of outline and position of stomach as indicated by skiagrams taken on 

 man in the erect position at intervals after swallowing food impregnated with bismuth subnitrate. 

 A, moderately full; B, practically empty. The clear space at the upper end of the stomach is due 

 to gas, and it will be noticed that this "stomach bladder" lies close to the heart. (From T. Win- 

 gate Todd.) 



