Mucous membrane lines all those passages by which the internal parts
communicate with the exterior, and is continuous with the skin at the
various orifices of the surface of the body. The mucous membrane,
beginning with the lips, lines the mouth, throat, œsophagus, stomach,
and in short, the entire alimentary canal. It also lines the nares,
larynx, bronchial tubes, and air cells. It is one because unbroken. Its
function is to secrete mucous for the purpose of preventing dryness.
Sympathetic relations exist throughout the whole human system, and
especially between different parts of the same organ; if one part of the
mucous membrane is injured, another part is as liable to suffer as that
immediately injured. If congestion takes place in any part of this
mucous membrane, it may cause congestion in some remote part of the
membrane, without affecting the intervening parts. There is a certain
common misuse of the voice which creates in the pharynx an irritation
called “clergyman’s sore throat.” By the law of sympathy, this
congestion is likely to be communicated from the pharynx to the mucous
membrane of the stomach. It may also attack the mucous membrane of the
bronchial tubes and through them affect the lungs.
Although this disease caused by the misuse of the voice is called
“clergyman’s sore throat,” it is not confined to clergymen; it prevails
to a considerable extent among school teachers, lawyers, and
auctioneers. It is dangerous for one to enter upon any form of public
speaking without having a sufficient knowledge of the voice to use his
own correctly. This is true not merely because it gives power to speak
more effectively, but because it enables one to preserve his own health,
and thereby prolong his usefulness. “Clergyman’s sore throat” is caused
by making too close a chamber of resonance in the pharynx while
speaking. This is a confirmed habit with a very large number of persons;
in fact, it might almost be said to be a prevailing difficulty, but it
does not always cause a sore throat until the voice is more constantly
used than it ordinarily is in private life.
A clergyman or others may for years have practised this habit without
feeling the effect upon the throat; but as soon as they come to speak
steadily for a half hour or more, and that, too, for the purpose of
being heard in a large room, begin to realize a huskiness which soon
develops into an irritation of the throat.
This finally develops into a congestion, and sooner or later into a
cough, which results in the breaking down of the powers of the
individual, and if it does not receive immediate and proper attention
consumption may be the result. No medicine, however good, can give more
than a temporary relief. So long as the cause (which is the misuse of
the voice), remains, the difficulty must return. Sometimes “clergyman’s
sore throat” is not introduced by huskiness; the first symptom observed
is that of dryness or irritation. This is especially true if the voice
is characterized by a metallic element. All these evils can be cured by
proper vocal education, providing the patient does not wait too long.
[Illustration: =CONVOLUTIONS AND FISSURES OF THE OUTER SURFACE OF THE
CEREBRAL HEMISPHERE.=]
=_RELATION OF THE PROPER USE OF THE VOICE TO THE NERVOUS SYSTEM._=
The vocal organs may be said to be tools, and the nerves the workmen
appointed to use them.
Nerves are whitish and elastic bundles of fibers, with their
accompanying tissues. They transmit nervous impulses between nerve
centers and various parts of the animal body.
“Nerves are composed of one or more (sometimes nearly a hundred)
nerve fibers, each fiber forming a means of communication
between two parts more or less distant from each
other.”—_Dutton._
The brain is contained in the cranium, and may be said to be the
controller of the entire nervous system. From it proceed twelve pairs of
cranial nerves.
I. Olfactory, nerve of smell,—distributed in the mucous membrane of the
nose.