146 ANALYTIC | SECT. XVIII. 
SECTION XVIII. 
Irritability of the Alimentary Canal. 
cccLxi1l. Besides the expansibility derived from 
the vital force, all the soft fibrous texture is ca- 
pable of more or less mechanical extension. The 
coats of the intestines, which are comparatively 
contracted when empty, undergo great distention 
by repletion; but it is not to’ be forgotten, that 
while they are thus mechanically distended, they 
are, at the same time, pervaded by the vital force. 
As the alimentary canal is in constant contact 
with extraneous bodies, which it has to decom- 
pose for the support of the other organs, its 
irritability is liable to great variation. 
cccLxiv. When the repletion of the stomach 
is moderate, the alimentary mass causes an in- 
finity of contractile movements in its coats; and 
as it is decomposed, it is forced successively along 
the intestinal tube, in a manner nearly similar 
to the motion of the lymph in the absorbents, 
excepting, perhaps, the power of suction possessed 
by the latter. But if the repletion of the stomach 
