612 DIGESTION, 



by Dr. Blundell 1 and Sir B. Brodie in their experiments to the re- 

 establishment of the choledoch duct, by the effusion of lymph around 

 the tied part, and the subsequent dropping off of the ligature. Like 

 Sir B. Brodie, Mayo, Leuret and Lassaigne, and Voisin, they observed 

 that chymification went on as in the sound animal. 



The thoracic duct and chyliferous vessels, in animals fed a short time 

 before death, always contained an abundant fluid, which was generally 

 of a yellowish colour. It coagulated like ordinary chyle; the crassa- 

 mentum acquired the usual red colour; and the only difference between 

 it and the chyle of a sound animal was, that after tying the duc"t it was 

 never white. They conceived the reason of the difference to be, that 

 the white colour is owing to fatty matter taken up from the food by the 

 agency of the bile, which possesses the power of dissolving fat; and 

 may probably, therefore, aid in effecting its solution in the chyle in the 

 radicles of the chyliferous vessels. Sir Benjamin Brodie and Mr. Mayo 

 are considered to have been misled by the absence of the white colour^ 

 usually possessed by the chyle, but which is wanting in ordinary diges- 

 tion, if the food does not contain fatty matter. 2 The experiments of 

 Dr. Beaumont showed, that oil undergoes but little change in the sto- 

 mach, and that bile is probably necessary to give it the requisite physical 

 constitution, in order that chyle may be separated from it. Messrs. 

 Tiedemann and Gmelin restrict the agency of the bile in chylifieation 

 to the accomplishing of the solution of the fatty matter, and to the 

 nitrogenizing or animalizing of food that does not contain nitrogen. 

 The experiments of M. Voisin equally show, that the ligature of the 

 choledoch duct does not prevent the formation of chyle, provided the 

 passage of the pancreatic fluid is not at the same time prevented. In 

 a number of dogs, a ligature was applied so as to completely prevent 

 the passage of bile into the intestine. Two lived three months after 

 the experiment; three, six weeks; and five died shortly after the appli- 

 cation of the ligature. In no instance did death appear to be owing 

 to the suspension of digestion or assimilation. Almost all the animals 

 had begun to eat; and, in the majority, food perfectly chymified was 

 found in the duodenum ; and well elaborated chyle in the chyliferous 

 vessels. It would appear, therefore, that the bile, although an import- 

 ant, is not an essential agent in digestion in the duodenum. This is 

 signally corroborated by the cases of two infants, four or five months 

 old, recorded by Dr. Blundell. The hepatic ducts in both cases ter- 

 minated blindly, so that no bile entered the intestines; the evacuations- 

 were white like spermaceti, and the skin jaundiced. Yet they grew 

 rapidly, and throve tolerably. 



No certain knowledge exists, whether any of the elements of the 

 bile are absorbed in the form of chyle ; or whether it acts mainly as a 

 precipitate, and is thrown off with the excrement. As elsewhere shown, 

 however, it is largely excrementitious or depurative. 



As to the mode in which the biliary and pancreatic fluids act on the 



1 Researches, Physiological and Pathological, London, 1825; and Elliotson's Physiology, 

 p. 124, London, 1840. 



2 Edinb. Med. and Surg. Journal, xciii.; and Mayo, Outlines of Hwman Physiology, 4th 

 edit., p. 139, London, 1837. 



