The œsophagus is a slightly flexuous canal, inclining to the left in
the neck, to the right in the upper part of the thorax; it commences
at the termination of the pharynx, which is a musculo-membranous sac,
about four inches in length, and communicating with the cavity of
the nose and mouth; the œsophagus then passes behind the arch of the
aorta to the œsophagal opening in the diaphragm, where it enters the
abdomen, and terminates into the stomach.
The stomach in man is an oblong, membranous bag, placed obliquely
across the abdomen and just below the diaphragm; its average capacity
in the adult is about one quart; it has two openings, one towards the
heart called the _cardiac orifice_, which receives the food from the
œsophagus, and the other at the right or small end of the stomach,
called the pyloric orifice, for the transmission of food to the small
intestines.
The small intestines, about twenty-five feet in length, are coiled in
various directions, and terminate into the large intestine, called
the colon, which is about five feet in length, and resembles in
appearance a long sac divided into numerous pouches.
The pancreas is a long narrow gland, situated partly behind the
right side of the stomach, and within the first curve of the small
intestine.
The liver is the largest gland in the body; it is situated on the
right side, below, and in contact with the diaphragm, and is divided
into several lobes. At its lower side is the gall bladder, into which
the bile is poured after being secreted. Its duct opens into a duct
leading direct from the liver, and forms with it the common bile
duct, through which the bile is poured into the small intestine, at
the same point with the duct from the pancreas, until, at length, it
is carried with the food into the larger intestine or colon, from
whence it is excreted from the system, through the rectum.