ts blood vessels that compose it as a gland, are the
branches of the vena portarum, which, as I mentioned in the last
lecture, enters the liver and distributes its blood like an artery.
From this blood the liver secretes the bile, which is conveyed by the
hepatic duct, towards the intestines: before this duct reaches the
intestines, it is joined by another, coming from the gall bladder:
these two ducts uniting, form a common duct, which enters the
duodenum obliquely, about four inches below the pylorus of the
stomach.

The gall bladder, which is a receptacle of bile, is situated between
the stomach and the liver; and the bile which comes from the liver,
along the hepatic duct, partly passes into the duodenum, and partly
along the cystic duct into the gall bladder. When the stomach is
full, it presses on the gall bladder, which will squeeze out the bile
into the duodenum at the time when it is most wanted.

The bile is a thick bitter fluid, of a yellowish green colour,
composed chiefly of soda and animal oil, forming a soap; and it is
most probably in consequence of this saponaceous property that it
assists digestion, by causing the different parts of the food to
unite together by intermediate affinity. When the bile is prevented
from flowing into the intestines, by any obstruction in the ducts,
digestion is badly performed, costiveness takes place, and the
excrements are of a white colour, from being deprived of the bile.
This fluid, stagnating in the gall bladder, is absorbed by the
lymphatics, and carried into the blood, communicating to the whole
surface of the body a yellow tinge, and other symptoms of jaundice.

The jaundice therefore is occasioned by an obstruction to the passage
of the bile into the intestines, and its subsequent absorption into
the blood: this obstruction may be caused either by concretions of
the bile, called gall stones, or by a greater viscidity of the fluid,
or by a spasm, or paralysis of the biliary ducts.

The pancreas, or sweet bread, is a large gland lying across the upper
and back part of the abdomen, near the duodenum. It has a short
excretory duct, about half as wide as a crow quill, which enters the
duodenum at the same place where the bile duct enters it.

The food being received into the mouth, is there masticated or broken
down, by the teeth, and impregnated with saliva, which is pressed out
of the salivary glands, by the motions of the jaw and the muscles of
the mouth. It t