of the careful design of nature in this
respect. The nostrils are two narrow, tortuous channels, containing
numerous bristly hairs which serve the purpose of a filter or sieve to
strain the air of its impurities, etc., which are expelled when the
breath is exhaled. Not only do the nostrils serve this important
purpose, but they also perform an important function in warming the
air inhaled. The long narrow winding nostrils are filled with warm
mucous membrane, which coming in contact with the inhaled air Warms it
so that it can do no damage to the delicate organs of the throat, or
to the lungs.

No animal, excepting man, sleeps with the mouth open or breathes
through the mouth, and in fact it is believed that it is only
civilized man who so perverts nature's functions, as the savage and
barbarian races almost invariably breathe correctly. It is probable
that this unnatural habit among civilized men has been acquired
through unnatural methods of living, enervating luxuries and excessive
warmth.

The refining, filtering and straining apparatus of the nostrils
renders the air fit to reach the delicate organs of the throat and the
lungs, and the air is not fit to so reach these organs until it has
passed through nature's refining process. The impurities which are
stopped and retained by the sieves and mucous membrane of the
nostrils, are thrown out again by the expelled breath, in exhalation,
and in case they have accumulated too rapidly or have managed to
escape through the sieves and have penetrated forbidden regions,
nature protects us by producing a sneeze which violently ejects the
intruder.

The air, when it enters the lungs is as different from the outside
air, as is distilled water different from the water of the cistern.
The intricate purifying organization of the nostrils, arresting and
holding the impure particles in the air, is as important as is the
action of the mouth in stopping cherry-stones and fish-bones and
preventing them from being carried on to the stomach. Man should no
more breathe through his mouth than he would attempt to take food
through his nose.

Another feature of mouth-breathing is that the nasal passages, being
thus comparatively unused, consequently fail to keep themselves clean
and clear, and become clogged up and unclean, and are apt to contract
local diseases. Like abandoned roads that soon become filled with
weeds and rubbish, unused nostrils become filled with impurities and
fou