34:6 DIGESTION. 



is well known that many of the German experimenters op- 

 erated with pancreatic juice which was not coagulahle, and 

 which Bernard regards as abnormal and incapable of digest 

 ing fat. With regard to the observation upon the lacteals of 

 the rabbit, by following out carefully the directions given by 

 Bernard, and injecting into the upper part of the intestine of 

 this animal a small quantity of a solution of fat in ether, we 

 have seen the lacteals appear just at the orifice of the pan 

 creatic duct and below it, while they were absent above. 1 



The pancreatic juice is the only one of the digestive fluid? 

 which is capable of forming a complete and permanent emul- 

 sion with fats. The fact that the other digestive fluids will 

 not accomplish this is easily demonstrated as regards saliva, 

 gastric juice, and bile. The intestinal juice is then the only 

 one which might be supposed to have this property. The 

 observations of Busch on this point, in his case of intestinal 

 fistula, are conclusive. He found that fatty matters taken 

 into the stomach were discharged from the upper opening in 

 the intestine in the form of a fine emulsion, and were never 

 recognizable as oil ; but that fat introduced into the lower 

 intestinal opening was not acted upon, and was discharged 

 unchanged in the faeces. 2 



Another peculiarity noted by Bernard in the emulsion 

 resulting from the action of pancreatic juice upon fats is that 

 it persists when diluted with water, and will pass through a 



J It has been shown by Bernard that ether is one of the most powerful ex- 

 citants of the pancreatic secretion ; and consequently when fat in solution in 

 ether is introduced into the intestinal canal, the secretion is poured out in abun- 

 dance, and the fat is immediately emulsified. (Lemons sur les Effets des Sub- 

 stances Toxiques et Medicamenteuses, Paris, 1857, pp. 417, 418.) 



The observations of Bernard upon rabbits were fully confirmed in a series 

 of experiments performed under the direction of Prof. Samuel Jackson, of Phila- 

 delphia. He fed these animals with fat and vegetables in the way indicated 

 by Bernard, and never saw the lacteals fully injected with chyle above the open- 

 ing of the pancreatic duct. (American Journal of the Medical Sciences, October, 

 1854.) 



2 BUSCH, in YIRCHOW'S Archiv, Berlin, 1858, Bd. xiv., S. 165, 175 ; and 

 American Journal of the Medical Sciences, July, 1860, pp. 219, 220. 



