356 DIGESTION. 



acid and the fatty acids. This putrefactive action does not 

 take place in albuminoids which have been precipitated 

 after having been cooked, nor in raw gluten or caseine. 

 The presence of fat also interferes with putrefaction; so 

 that Bernard concludes that the fats have an important 

 influence in the intestinal digestion of nitrogenized princi- 

 ples. 1 The observations of Corvisart, who experimented, 

 however, with an artificial fluid formed by infusing the fresh 

 pancreas in water, were made in order to prove the great 

 activity of the pancreatic juice in the digestion of albuminoid 

 substances. Though these experiments are frequently re- 

 ferred to as throwing considerable light upon a function of 

 the pancreas but little known, the author of them does not 

 seem, in their execution, to have fulfilled the necessary phy- 

 siological conditions ; and his results cannot, therefore, be 

 accepted as definite and conclusive. 2 



Taking into consideration what has been positively ascer- 

 tained concerning the action of the pancreatic juice upon the 



1 Op. cit., pp. 129 and 130. 



2 CORVISART, Sur une Fonctionpeu connue du Pancreas, Paris, 185 7-1 858, and 

 Collection de Memoir es sur une Fonctionpeu connue du Pancreas, Paris, 1857- 

 1863. In the experiments upon the digestion of albuminoids in the duodenum 

 of a living animal, the intestine was exposed, the duodenum washed out with a 

 stream of tepid water, and albumen or some other substance introduced ; the duo- 

 denum being isolated from the rest of the intestine by two ligatures. That normal 

 digestion and absorption can take place under these conditions is not conceivable. 

 Again, in experimenting upon the action of the pancreatic juice out of the body, 

 the pancreatic secretion is never used, but an infusion of the tissue of the gland 

 is substituted. Though something may be learned by experimenting in this way, 

 results thus obtained should be compared with those which are obtained by using 

 the actual secretion of the gland. By using all the precautions recommended 

 by Corvisart in a paper published in reply to certain objections made to his ex- 

 periments, by Dr. Brinton (Journal de la Physiologic, Paris, 1860, tome iii., p. 

 473 et seq.\ we have never been able to manufacture a pancreatic juice with 

 which we could demonstrate to a medical class the characteristic properties of 

 the normal secretion. Corvisart does not seem to have verified any of his obser- 

 vations by operating with the actual secretion of the pancreas ; and, on the other 

 hand, has written several memoirs to show that infusions of the tissue of glands 

 resemble the natural secretions more closely than the fluids obtained from their 

 ducts. 



