132 PHYSIOLOGY OF ORGANIC LIFE. 



it, it is generally believed that the bile which 

 the liver secretes, is merely intended to acce- 

 lerate its expulsion/ It is far otherwise ; the 

 internal surface of the canal is increased, to a 

 very considerable extent, by means of a num- 

 ber of ridges, or folds, which, at first, are nearly 

 concentric to each other, but which gradually 

 acquire a diagonal direction. Since, then, the 

 alimentary canal is constructed with a view to 

 retard the motion of the food through the first 

 part of its course it is most unreasonable to 

 suppose, that the real and direct intention of 

 the hepatic system, is to hasten its expulsion. 

 If this were the case, instead of harmony, 

 there would be perpetual warfare between 

 both : the retarding construction of the intes- 

 tines would always tend to prevent, what the 

 bile was designed to accelerate, and the ductus 

 communis, in such a case, instead of having its 

 orifice in the duodenum, ought to have it in the 

 rectum. Those who can reconcile this warfare 

 of parts that are dependent upon each other, 

 have very inadequate notions of the symmetry 

 that pervades the whole of the system, and of 

 the harmony that exists between the parts of 

 which it is composed. So far from supposing 

 that the primary use of bile is intended to de- 

 feat the end for which the intestinal, (or the 

 chylous canal, as it ought more properly to be 

 called,) is so peculiarly constructed ; I think it 



