26 THE SECRETIONS: 



hindered ; 2d, that the contents of the small intestine, csecum, 

 and large intestine, after the application of a ligature to the 

 ductus communis choledochus, do not differ in any essential degree 

 from their ordinary state ; and 3d, that the bile plays no essential 

 part in the formation of chyle. 



Notwithstanding these general conclusions, they found that 

 the chyle of dogs, in whom the ductus communis choled. was 

 tied, was perfectly clear, whilst in the natural state it is white 

 and turbid in consequence of the fat held in suspension, a diffe- 

 rence not to be passed over as altogether unimportant. Another 

 undeniable effect of the bile in chylification consists in the neu- 

 tralization of the free acid of the chyme by the alkali that is as- 

 sociated in so unstable a manner with the biliary secretion, in 

 consequence of which the bilin gradually begins to undergo 

 certain changes, but whether of the same nature as in the labo- 

 ratory of the chemist it is impossible to decide. 



[That the bile is not merely an excrementitious fluid, in- 

 tended to remove effete matter from the blood, but that it 

 is a secretion essential to the animal economy, was rendered 

 almost certain by the experiments of Berzelius, Theyer, and 

 Schlosser, which showed that the human faeces contained much 

 too small a quantity of a substance resembling bile to justify 

 the idea that it is evacuated in this manner. A further proof 

 that the bile is absorbed and not excreted is afforded by an 

 examination, made by Enderlin, of the ash yielded by the con- 

 tents of the different portions of the intestinal canal of a hare. 

 He found that the ash from the contents of the duodenum alone 

 effervesced on the addition of an acid, thus showing that the 

 choleate of soda (which yields the carbonate on incineration,) 

 is absorbed before reaching the jejunum. Schwann has re- 

 cently established this opinion beyond a doubt, by a series of well- 

 devised experiments on dogs. He tied the ductus communis cho- 

 ledochus, and at the same time formed a fistulous opening in the 

 gall-bladder, by which the bile escaped externally. His most 

 important conclusions are, 1st, That when the bile does not get 

 into the bowel, its absence is generally perceptible in dogs, 

 about the third day, by a marked diminution in weight ; and, 

 2dly, That unless the channel for the conveyance of bile to the 

 duodenum is re-established, symptoms of deficient nutrition, 



