THE INTESTINAL HOKMONE 129 



way into the intestine; and that this hormone, once 

 produced, finds its way to the pancreas via the 

 blood stream. You will notice incidentally that 

 if what we now say is true, the intestine is similar 

 to the pancreas and, according to Claude Bernard, 

 to the liver, in that it elaborates both an internal 

 and an external secretion. 



The proof that the flow of pancreatic juice is con- 

 trolled by a hormone elaborated by the intestine 

 is due to Bayliss and Starling, the presiding gen- 

 iuses of the department of physiology at Univer- 

 sity College, London. Their experiment marks a 

 milestone in the development of our knowledge of 

 internal secretions; and we shall offer no excuse 

 for quoting from part of their celebrated paper on 

 the subject, technical though it is. 



Bayliss and Starling's experiment. "On Janu- 

 ary 16, 1902, a bitch of about 6 kilos (13-14 pounds) 

 weight which had been fed about 18 hours previ- 

 ously, was given a hypodermic injection of morphia 

 some three hours before the experiment. The ner- 

 vous masses and celiac (pertaining to the abdomen) 

 axis were completely removed, and both vagi 

 (nerves situated in this part of the body) cut. A 

 loop of jejenum (a portion of the small intestine) 

 was tied at both ends, and the nerves supplying it 

 were carefully dissected out and divided, so that 

 the piece of intestine was connected to the body of 

 the animal merely by its arteries and veins. A 



