aches the stomach, the gastric glands are excited
to action, and they secrete a powerful solvent, called gastric juice.
The presence of food in the stomach also increases a contractile
action of the muscular coat, by which the position of the food is
changed from one part of this cavity to another. Thus the aliment is
brought in contact with the mucous membrane, and each portion of it
becomes saturated with gastric juice, by which it is softened, or
dissolved into a pulpy homogeneous mass, of a creamy consistence,
called _Chyme_. The food is not all converted into chyme at the same
time; but as fast as it is changed, it passes through the pyloric
orifice into the duodenum.

_Observation._ The gastric juice has the property of coagulating
liquid albuminous matter when mixed with it. It is this property of
rennet, which is an infusion of the fourth stomach of the calf, by
which milk is coagulated, or formed into "curd."

265. The CHYME is conveyed through the pyloric orifice of the stomach
into the duodenum. The chyme not only excites an action in the
duodenum, but also in the liver and pancreas. _Mucus_ is then secreted
by the duodenum, _bile_ by the liver, and _pancreatic fluid_ by the
pancreas. The bile and pancreatic fluid are conveyed into the
duodenum, and mixed with the chyme. By the action of these different
fluids, the chyme is converted into a fluid of a whitish color, called
_Chyle_, and into residuum.

_Observation._ The bile has no agency in the change through which
the food passes in the stomach. In a healthy condition of this
organ, no bile is found in it. The common belief, that the stomach
has a redundancy of this secretion, is erroneous. If bile is ejected
in vomiting, it merely shows, not only that the action of the
stomach is inverted, but also that of the duodenum. A powerful
emetic will, in this way, generally bring this fluid from the most
healthy stomach. A knowledge of this fact might save many a stomach
from the evils of emetics, administered on false impressions of
their necessity, and continued from the corroboration of these by
the appearance of bile, till derangement, and perhaps permanent
disease, are the consequences.

266. The CHYLE and residual matter are moved over the mucous surface
of the small intestine, by the action of its muscular coat. As the
chyle is carried along the tract of the intestine, it comes in contact
with the villi, where the lacteal vessels commence. These imbibe