CHAP. XXV.] CHANGES OF FOOD IN THE SMALL INTESTINE. 241 



and in the white-chyle, chyle globules, fat globules and molecular 

 base.* 



It would seem to follow, from observing the changes which the 

 food undergoes in the small intestine, that the immediate office of 

 that portion of the intestinal canal is to form this chyle ; and it 

 appears probable that the secretions poured into the small intestine 

 from the glands, especially the liver, pancreas, and the glands of 

 Brunner, which communicate with it, exercise a chemical influence 

 upon the alimentary matters whereby this material is formed. We 

 shall see, further on, that this view receives strong support from the 

 results of experiments and observations respecting the functions of 

 the pancreas and liver. 



Changes of the Food in the Small Intestine. It remains now to 

 inquire whether all the digestible food which passes from the stomach 

 undergoes the change into chyle, or whether certain parts of it only 

 are simply dissolved and pass by absorption directly into the portal 

 blood, as in the stomach, whilst other parts are converted into chyle, 

 and enter a different part of the circulation through the lacteal 

 vessels. In other words, is it necessary that all food, prior to its 

 appropriation by the blood as nutriment, should pass through the 

 condition of chyle ? 



As it has been shown that the stomach can absorb certain fluids 

 and dissolved solids, through the absorbing power of its blood- 

 vessels, there can be no good reason for denying the same power 

 to the intestines, which have a vascular system precisely of the 

 same kind as that of the stomach. Now the substances which 

 the stomach completely dissolves and absorbs, are the azotised ali- 

 ments : it seems not unreasonable to conclude that such portions 

 of these aliments as have escaped absorption by the stomach, may 

 undergo a similar solution in the intestines, and be absorbed by 

 their blood-vessels without passing through the state of chyle. 



But to answer this question accurately, we must determine pre- 

 cisely the changes which each kind of food undergoes in the intestine. 



Bouchardat and Sandras have obtained from their experiments 

 results which indicate that fibrine does not undergo the change 

 into white chyle. They fed animals with fibrine, coloured with 

 saffron or cochineal, and were unable to detect any trace of the 

 colouring matter in the chyle. They found, likewise, that the con- 

 tents of the lacteal vessels of animals kept fasting differed in no 

 respect from that of animals fed on fibrine. These experiments, 

 therefore, render it highly improbable that fibrine contributes to the 

 * See the Chapter on ABSORPTION. 



