INTESTINAL DIGESTION. 
193 
Intestinal Digestion; Ghylification . 
212. The process of digestion is by no means completed in 
the stomach; for much of the matter which escapes from it 
in the chyme, is destined to undergo a further change whilst 
passing through the intestinal canal; especially in the her¬ 
bivorous tribes, whose food, being less digestible than that of 
the carnivorous races, requires to be longer delayed in the 
intestinal canal, in order that it may yield up its nutritious 
portion. Hence we find this canal of enormous extent in 
most animals whose food is vegetable, being in the Sheep 
about twenty-eight times the length of the body; in the 
purely carnivorous animals, on the other hand, it is compara¬ 
tively short, being in the Lion only about three times the 
length of the body, while in the Serpent it runs almost 
straight from one extremity to the other; and in animals 
which live on a mixed diet, it is of medium length, being 
in Man about six times as long as his body. The intes¬ 
tinal tube is usually distinguished into the small and the 
large intestine ; of which the small is the first portion, and 
the large the second. The former, as shown in fig. 108, is 
disposed in a convoluted or twisted manner, so that a great 
extent of it may be packed within a small compass ; it 
usually forms about three-fourths of the whole length of the 
canal. It is held in its place by a serous membrane termed 
the 'peritoneum , which forms an immense number of folds 
that suspend it (as it were) from the vertebral column; but 
these still allow it a considerable power of movement. 
213. Soon after passing from the stomach into .the intes¬ 
tinal canal, the food is mingled with three secretions, which 
have an important influence on the changes it is further to 
undergo; these are the Bile, the Pancreatic fluid, and the In¬ 
testinal juice. The two former are prepared by two large glan¬ 
dular masses, the Liver and the Pancreas (or sweetbread), 
which, in all the higher animals, are completely detached 
from the alimentary canal, and send their secretions into it 
through special ducts ; the latter, like the gastric juice, is 
formed in little follicles lodged in the wall of the canal itself. 
The peculiar matter which forms the chief solid constituent of 
bile, is essentially a soap formed by the union of two resinoid 
acids, with soda as a base (§ 364). The composition of the 
o 
