DIGESTION IN THE STOMACH. 



61 



he had to be fed through the gastric fistula, but whence was al- 

 lowed to chew food for which he had a relish and then spit it out, 

 gastric secretion occurred. This observation suggested to Paw- 

 low the establishment of analogous conditions in dogs, with the 

 modification that, besides the fistula in the stomach, one was 

 made of the oesophagus in the neck in such a way that swallowed 

 food escaped by it. The animal could therefore swallow inter- 

 minably without ever becoming satisfied, and it was observed 



Fig. 5. Diagrams of outline and position of stomach as indicated by skia- 

 grams 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. (T. 

 Wingate Todd.) 



that when it did so, gastric juice flowed, provided this "sham 

 feeding" was with appetizing food. Stones, bread, acid or irri- 

 tating substances, although they might cause much saliva to be 

 secreted and swallowed (see p. 43), had no influence whatso- 

 ever on the flow of gastric juice. The only adequate stimulus 

 was gratification of the appetite. 



