PHYSIOLOGY OF THE PANCREAS. 105 



tine very low down, from six to fourteen inches below the hepatic duct, and if fatty 

 matter be introduced into the stomach, and the animal killed in three or four 

 hours, it will be found to have become an emulsion, and the lymphatics of the 

 mesentery filled with white chyle only below the opening of the pancreatic duct. 

 M. CI. Bernard further showed that if fatty bodies be exposed to the pancreatic 

 fluid, out of the body, a complete emulsion is formed, and, if it be allowed to 

 remain long enough, the fatty substances will be decomposed into glycerine and 

 fatty acids, and, in the case of butter, butyric acid. Parallel experiments instituted 

 with other fluids — as bile, saliva, gastric juice, serum of the blood — produce no such 

 effects on fatty bodies. 



It was probably supposed that fat was, in the animal economy, resolved into 

 glycerine and fat acids. This process, however, would be very complicated, and 

 involves many difficulties, and it is more reasonable to conclude that the action of 

 the pancreatic juice is limited to the formation of an emulsion, which is nothing 

 more than the mechanical division of the fat into minute globules, coated with a 

 thin film of the albuminoid elements of the pancreatic juice. That this is really 

 the case in living animals, I enjoyed many opportunities of rendering apparent, 

 whilst examining the pancreas of the Garfish (Lepisosteus osseus). In this fish, the 

 duct of the pancreas has a diameter almost equal to that of the intestine, and is so 

 situated that all the digested matters which pass out of the stomach must come 

 in contact with its secretion, and often pass, in considerable amount, into the duct 

 and caeca of the gland. When the emulsion is squeezed out, and subjected to the 

 microscope, it is found to consist of innumerable minute globules of oil, surrounded 

 by a transparent fluid. 



The correctness of M. Bernard's observations has been called in question by 

 Drs. Bence Jones, Lenz, Frerichs, Bidder, Schmidt, Lehmann, Donders, and Herbert. 

 It is asserted that the bile and intestinal juice are even more active and efficient 

 than the pancreatic juice, in the preparation of fatty matters for absorption. It is 

 objected to Bernard's experiments, that he delayed his examination of the animals 

 too long, and allowed the emulsion, formed with the bile, to pass down and be 

 absorbed, before inspecting the viscera of the rabbits. 1 



Dr. Samuel Jackson, Professor of the Institutes of Medicine in the University 

 of Pennsylvania, has recently examined this subject carefully, and repeated the 

 experiments of Bernard, avoiding every source of error, and especially that of time, 

 by causing oleaginous matters to enter the digestive apparatus, constantly, until the 

 moment of observation. In every instance the results of his experiments confirmed 

 the correctness of Bernard's conclusion, that the emulsion of fatty matters is pro- 

 duced by the action of the pancreatic juice. The doctor concludes his valuable 

 paper by the following summary of the present state of our knowledge on this 

 point : — 



"1. Liquid fats are not miscible with the aqueous albumino-saline fluid — liquor 



1 American Journal of the Medical Sciences, October, 1854, p. 307. 

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