ACTION OF THE SMALL INTESTINE. 613 



chyme, we have not had, until recently, much more than conjectures to 

 guide us. MM. Tiedemann and Gmelin suggest, that the soda of the 

 bile unites with the chlorohydric and acetic acids of the chyme ; and 

 simultaneously the latter precipitates the mucus of the bile and its 

 colouring principle and resin, which are evacuated with the excrements. 

 The majority of physiologists believe, that bile is divided into two parts, 

 by the action of the chyme; the one containing the alkali, salts, and 

 a part of the animal matter uniting with the chyle; the other con- 

 taining the coagulated albumen, the coloured, concrete, acrid, and bitter 

 oil uniting with the fseces, to be discharged along with them. Ac- 

 cording to this. view, the action of the bile would be purely chemical; 

 a part would be recrementitial or taken up again; and a part excre- 

 mentitial, giving to the excrements their smell and colour; and, accord- 

 ing to some, the necessary stimulating property for exciting the flow of 

 the intestinal fluids, and soliciting the peristaltic action of the intestines 

 so as to produce their evacuation. It is more than doubtful, however, 

 whether the bile have any such influence as the last. It is a law in the 

 economy, that no secretion irritates the part over which it passes, or is 

 naturally destined to pass, unless such part is in a morbid condition ; and 

 were it otherwise, the mucous membrane of the intestine would be soon 

 accustomed to the stimulation ; and, the effect be null. MM. Tiedemann 

 and Gmelin further suggest, that from the abundance of highly nitro- 

 genized principles, which the bile contain's, it probably contributes to 

 animalize those articles of food, that do not contain nitrogen; and that 

 it may tend to prevent the putrefaction of the food in its course through 

 the intestines, inasmuch as when it is prevented from flowing into them, 

 their contents appear much farther advanced in decay than in the 

 healthy state. It has been held of late, that bile has the power of 

 transforming saccharine aliments into fat; a circumstance, which is 

 favoured by the discovery of H. Meckel, 1 that when sugar is mixed with 

 bile out of the body a part of it is converted into fatty matter. Ad- 

 mixture with the pancreatic juice would then render its absorption easy. 

 (See SECRETION OF BILE.) 



We were not instructed until of late in regard to the precise uses of the 

 pancreatic juice; although many have been assigned to it, which being 

 founded in ignorance of its nature and properties, it would be a waste 

 of time to notice. Messrs. Tiedemann and Gmelin affirm, that it yields 

 to the chyme the richly nitrogenized principles, that enter into its com- 

 position; and, consequently, aids in assimilation. In testimony of this, 

 they remark, that the pancreas is larger in herbivorous than in carnivo- 

 rous animals; and that, in proportion as the chymous matter proceeds 

 along the intestinal canal, it exhibits itself less rich in albumen and 

 other nitrogenized matters, which have probably been abstracted from 

 it by absorption. Dr. Marcet 2 discovered in the chyme of the small 

 intestine a notable development of albumen, which was first perceptible 

 a few inches from the pylorus, and did not exist in the large intestine; 

 and Messrs. Tiedemann and Gmelin found in the intestinal contents of 



5 Henle und Pfeufer, Zeitschrift fur rationelle Medicin; cited by Mr. Paget in Report in 

 British arid Foreign Medical Review, p. 261, July, 1846. 

 2 Medico-Chirurgical Trans., vi. 618. 



