The Jackson standard. [volume] (Jackson C.H., Ohio) 1847-1888, 1873-07-24
From the Scientific Americana
The Digestive Apparatus.

1t has rightly been said that the great
est object of study for man is man him
self; this is true in physical as we'll as
a moral sense The human body, indeed,
is almost a universe in itself, including
many kinds of physical apparatus, dynam-
ioal, hydraulic, etc. The system of bones
and muscles gives an example of the most
perfect statical and dynamical arrange
ment; the heart, arteries, etc, of an adj
lnirable system of hydraulic contriv-
ances; the digestive apparatus is a most
complete chemical labratory in itself,
by which the material called food is met
amorphosed into the living tissue of
which man consists. We have, on a
former occasion, glanced over the most
striking features of mans hydraulic sys-
tenn, of which the heart is the main or
gan; let US now take a glance at the
chemical labratory which we carry with
us, of which the stomach is the main or
gan, and which, as well as the circulation
Of the blood. is carried on incessantly
independently of our will and, when per-
fect even without our knowledge.
The stomach is only one of the organs
necessary for digestion. This operation,
indeed, commences in the mouth, and
extends nearly throughout the whole
length of the so-called alimentary canal,
presents a surface, to be acted upon by
the food, of some 600 square inches. In
the mouth the food undergoes two oper-
ations, one mechanical and other chem
ical. The movements of the teeth, aided
by the tongue, grind it up into small par
ticles of proper size, while the simulta-
neous intermixture of the liquids Sc
creted from three pairs of saliyary glands
constitute the first chemical operation.
Coated with glary juice, the food passes
along the oesophagus into the stomach
(Which is only an expansion between the
esophagus and the duodenum); this con-
ssts of three coats, one mucous, one mus
cular, and one serous, which is exterior.
The interior or mucus coat has velvety
appearance, and is folded in wrinkles, so
as to admit of much extension, When
thus extended, certain appendages are
stimulated and secrete three more liquids
required for digestion. They are the
gastric pancreatic, and hillary juices.
The chemistry of these different agents
in the process of digestion has, during
our time, been most minutely investi-
gated The saliva consists of mixture
Of liquids, which differ from each of the
three pairs of glands from which they
originate; to these fourth liquid is
added, the buccal, proceeding from the
lining membrane of the whole mouth I;
this mixture has the capacity of changing
starch into grape sugar and further, into
Tactic acid, which is essential to normal
digestion At the same time, the atmos-
pheric oxygen is entangled in the saliva
during mastication, and exerts an import
ant influence in promoting the action OF
the saliva and gastric juice in the stom-
ach. ... a.
The practical lesson which we draw
from these we'll established facts are
most important in hygienic point OF
view 1t deeply impresses us with the
Importance OF we'll chewing our food, and
with the injury which we do ourselves by
eating hastily, by washing down imper
feetly masticated food with water, tea
coffee, or something worse, and (Which
is the most injurious of ally by indulgin!
! in the bad habit OF splitting, and thus in
tentionally wasting one of the main sub
stances required for healthy digestion