334: DIGESTION. 



some have pretended that the facts which he established had 

 been demonstrated before. 1 The following method for col- 

 lecting the pancreatic juice from a living animal, one which 

 we have repeatedly employed with success, is essentially that 

 recommended by Bernard : 



The animal generally employed by Bernard in these ex- 

 periments is the dog. Selecting one of tolerably large size, 

 he is secured to the operating table, and placed upon his left 

 side. An incision from three to four inches in length is then 

 made in the right hypochondrium, just below and parallel 

 with the border of the last rib. The parts are first divided 

 down to the fascia transversalis and the peritoneum. An 

 opening is then made into the abdominal cavity about half 

 the length of the incision through the skin and muscles; 

 which brings to view the duodenum and a portion of the 

 pancreas. The duodenum, with the pancreas attached to it, 

 is then carefully drawn out of the abdomen. The next step 

 is to introduce a small canula into the principal pancreatic 

 duct. In the dog, there are always two pancreatic ducts : a 

 small one, which opens into the intestine at or near the open- 

 ing of the bile-duct, and a principal duct, which is situated 

 about an inch below. To collect the juice, the tube should be 

 introduced into the principal duct. This is found by turning 

 the duodenum and pancreas so as to expose the posterior sur- 

 face of the gland, when the duct, which is very short and al- 

 most concealed by the tissue of the pancreas, may be seen 

 obliquely penetrating the intestinal wall. In the dog, the 

 pancreas is composed of two portions ; one, called the hori- 

 zontal portion, which is attached to the duodenum, and a ver- 

 tical p'ortion, which passes away from the intestine between 

 the folds of the mesentery. The duct is generally situated 

 near the point where the pancreas ceases to be attached to 

 the intestine. The tissue of the pancreas is to be carefully 



1 BERNARD, Memoirs sur le Pancreas, Paris, 1856. Lemons de Physiologie Ex- 

 perimentale, Paris, 1856. Lepons sur les Proprietes Physiologiques et Ics Altera- 

 tions Patholoyiques des Liquides de I* Organismc, Paris, 1859: 



