THE INTEGUMENT, OR SKIN.
_The Integument--Its Structure--The Nails and Hair--The Complexion--The
Sebaceous Glands--The Perspiratory Glands--Perspiration and its
Uses--Importance of Bathing--Different kinds of Baths--Manner of
Bathing--The Benefits of the Sun--Importance of Warm Clothing--Poisonous
Cosmetics._
[Sidenote: 1. What is the skin? Parts directly beneath? What is shown?]
1. THE INTEGUMENT.--The skin is the outer covering of the body. The parts
directly beneath it are very sensitive, and require protection. This is
shown whenever by accident the skin is broken, pierced, or torn off, the
bared surface being very tender, and painful to the touch. Nature has
provided the body with a garment that is soft, pliable, close-fitting, and
very thin, and yet sufficiently strong to enable us to come in contact with
the objects that surround us, without inconvenience or suffering.
[Sidenote: 2. Microscopic examination? What is the cutis? The cuticle?
Their union? How separated? What further is said of the cuticle?]
2. THE STRUCTURE OF THE SKIN.--When examined with the aid of the
microscope, the skin is found to be made up of two layers--the outer and
the inner. The inner one is called the _cutis_, or true skin; the outer one
is the _epidermis_, or scarf-skin. The latter is also known as the
_cuticle_. These two layers are closely united, but they may be separated
from each other. This separation takes place whenever, from a burn, or
other cause, a blister is formed; a watery fluid is poured out between the
two layers, and lifts the epidermis from the true skin.
Of the two layers, the cuticle is the thinner in most parts of the body,
and has the appearance of a whitish membrane. It is tough and elastic, is
without feeling, and does {42} not bleed, when cut. Examine it more
closely, and we observe that it is composed of minute flat cells, closely
compacted, and arranged layer upon layer.
[Sidenote: 3. Wearing out of the cuticle? What then? Variety in thickness
of cuticle? How accounted for?]
3. The outer layer is constantly being worn out, and falls from the body in
the form of very fine scales. It is, also, continually forming anew on the
surface of the inner layer. Its thickness varies in different parts of the
body. Where exposed to use, it is thick, hard, and horn-like, as may be
seen on the soles of the feet, or on the palms of the hands, especially of
those who are accustomed to perform much manual labor. This is an admirable
provision for the increased protection of the sensitive parts below the
skin against all extraordinary exposure. Even the _liabilities_ of these
parts to injury, are thus kindly provided for by "the Hand that made us."
[Sidenote: 4. Location and office of the cutis? What further is said of it?
Papillæ? Touch?]
4. The cutis, or true skin, lies beneath the epidermis, and is its origin
and support. It is firm, dense, elastic, very sensitive, and is freely
supplied with blood-vessels. It is closely connected with the tissues below
it, but may be separated by means of a sharp instrument. The surface of the
cutis is not smooth, but is covered here and there with minute elevations,
called _papillæ_. These are arranged in rows, along fine lines, or ridges,
such as those which mark the palm and fingers; their number is about 80 to
the square line (a line being one-twelfth of an inch). These _papillæ_
contain the blood-vessels which carry the supply of blood needed by the
ever-wasting skin. They contain nerves also, and are largely concerned in
the sense of touch; hence they are particularly abundant where the touch is
most delicate, as at the ends of the fingers.
[Sidenote: 5. What are the nails and hair? The growth of the nail? The
rapidity of its growth? Accident to the nail?]
{43} [Illustration: Fig. 14.
_a, b._ THE ROOT OF A HAIR.
1, 2, 3. The skin forming the hair sac. 4. Sebaceous glands. 5. The hair
sac.
_c._ TRANSVERSE SECTION OF A HAIR.]
5. THE NAILS AND HAIR.--These are appendages of the skin, and although very
unlike the cuticle as it appears on the surface of the body, they are, in
reality, modified forms of that layer of the skin. The nail grows from a
fold of the cuticle at the root, and from the under surface. As fast as it
is formed, it is constantly being pushed outward. The rapidity of its
growth can be ascertained by filing a slight groove on its surface, and
noticing how the space between it and the root of the nail increases, in
the course of a few weeks. When the nail is removed by any accident, it
will be replaced by a new one, if the root be not injured.
[Sidenote: 6. How are the hairs produced? Difference in their length?]
6. The hairs are produced in a similar manner; the skin forming
depressions, or hair sacs, from the bottom of which they grow and are
nourished (Fig. 14). They are found, of greater or less length, on almost
all parts of the surface, except the palms of the hands and soles of the
feet. On certain parts of the body, they grow to great length; on other
parts they are so short, that they do not rise beyond the hair sac in which
they originate.
[Sidenote: 7. Root of the hair? Shaft? Firmness and softness of the hair?]
7. The bulb, or root, from which the hair arises, is lodged in a small
pouch, or depression in the skin. The shaft is the part which grows out
beyond the level of the skin. Its growth is altogether in one direction, in
length alone. The outer part of the hair is quite firm, while its {44}
interior is softer, and probably conveys the fluids by which it is
nourished. The hair is more glossy in health than at other times.
[Sidenote: 8. Office of the nail? Of the hair? Give the illustrations.]
8. The nail serves as a protection to the end of the finger, and also
enables us to grasp more firmly, and to pick up small objects. The hair,
too, is a protection to the parts it covers. On the head, it shields the
brain from extremes of heat and cold, and moderates the force of blows upon
the scalp. On the body, it is useful in affording a more extensive surface
for carrying off the perspiration.
[Sidenote: 9. On what does the complexion depend? Light and dark races?
Freckles?]
9. COMPLEXION.--In the deeper cells of the cuticle lies a pigment, or
coloring matter, consisting of minute colored grains. On this pigment
_complexion_ depends; and, according as it is present in less or greater
amount, occasions the difference of hue, that exists between the light and
dark races of men, and between the blonde and brunette of the white races.
Freckles are due to an irregular increase of coloring matter.
[Sidenote: 10. Influence of the sun? How illustrated? Jews?]
10. The sun has a powerful influence over the development of this pigment,
as is shown by the swarthy hue of those of the white race who have
colonized in tropical climates. It is also well illustrated by the fact,
that among the Jews who have settled in northern Europe, there are many who
are fair complexioned, while those residing in India, are as dark as the
Hindoos around them.
[Sidenote: 11. What is an Albino? Where are Albinos found?]
11. An Albino is a person who may be said to have no complexion; that is,
there is an entire absence of coloring matter from the skin, hair, and
_iris_ of the eye. This condition more frequently occurs among the dark
races, and in hot climates, although it has been observed in almost every
race and clime.
[Sidenote: 12. What are sebaceous glands? How do they act? Sebaceous glands
of the face? How do they act?]
12. SEBACEOUS GLANDS.--There are in the skin certain {45} small glands,
which produce an oily substance, called _sebaceous_ matter. These glands
are little rounded sacs, usually connected with the hair-bulbs; and upon
these bulbs, they empty their product of oil, which acts as a natural and
adequate dressing for the hair (4, Fig. 14). A portion of the sebaceous
matter passes out upon the surface, and prevents the cuticle from becoming
dry and hard. The glands situated upon the face and forehead, open directly
upon the skin. In these, the sebaceous matter is liable to collect, and
become too hard to flow off naturally.
[Sidenote: 13. Black points, called worms? Animalcules? Service performed
by sebaceous matter?]
13. These glands on the face and forehead frequently appear, on the faces
of the young, as small black points, which are incorrectly called "worms."
It is true, that occasionally living animalcules are found in this
thickened sebaceous matter, but they can only be detected by the aid of the
microscope. This sebaceous matter acts not only to keep the skin flexible,
and furnish for the hair an oily dressing, but it especially serves to
protect the skin and hair, from the acridity arising from the perspiration.
[Sidenote: 14. Perspiration? Sweat glands? Of what do they consist?
Dimension of the tubes?]
14. THE PERSPIRATORY GLANDS.--The chief product of the skin's action is the
perspiration. For the formation of this, there are furnished countless
numbers of little sweat-glands in the true skin. They consist of fine
tubes, with globe-like coils at their deeper extremity. Their mouths or
openings may be seen with an ordinary magnifying glass, upon the fine
ridges which mark the fingers. These tubes, if uncoiled, measure about
one-tenth of an inch in length. In diameter, they are about one
three-hundredth of an inch, and upon certain parts of the body there are
not far from three thousand of these glands to the square inch. Their whole
number in the body is, therefore, very great; and, in fact, it is computed
if they were all united, end to end, their combined measurement would
exceed three miles. {46}
[Sidenote: 15. What is sensible perspiration? Insensible perspiration?]
15. THE SENSIBLE AND INSENSIBLE PERSPIRATION.--The pores of the skin are
constantly exhaling a watery fluid; but, under ordinary circumstances,
there is no moisture apparent upon the surface, for it evaporates as
rapidly as it is formed. This is called insensible perspiration. Under the
influence of heat or exercise, however, this fluid is excreted more
abundantly, and appears on the surface in the form of minute, colorless
drops. It is then termed sensible perspiration.
[Sidenote: 16. Components of perspiration? Upon what does perspiration
depend? Amount of perspiration daily?]
16. Water is the chief component of this fluid, there being about
ninety-eight parts of water to two parts of solid matter. The quantity
escaping from the body varies greatly, according to the temperature of the
air, the occupation of the individual, and other circumstances. The average
daily amount of this excretion, in the adult, is not far from thirty
ounces, nearly two pints, or more than nine grains each minute.
[Sidenote: 17. What does perspiration set free from the blood? What other
service does perspiration perform? Explain the process.]
17. THE USES OF THE PERSPIRATION.--Besides liberating from the blood this
large amount of water, with the effete matter it contains, the perspiration
serves to regulate the temperature of the body. That is to say, as
evaporation always diminishes temperature, so the perspiration, as it
passes off in the form of fine vapor, cools the surface. Accordingly, in
hot weather this function is much more active, and the cooling influence
increases in proportion. When the air is already charged with moisture, and
does not readily receive this vapor of the body, the heat of the atmosphere
apparently increases, and the discomfort therefrom is relatively greater.
[Sidenote: 18. Effect of interruption of excretion? What experiments are
mentioned?]
18. The importance of this excretion is shown by the effects that often
follow its temporary interruption, namely, headache, fever, and the other
symptoms that accompany {47} "taking cold." When the perspiration is
completely checked, the consequences are very serious. Experiments have
been performed upon certain smaller animals, as rabbits, to ascertain the
results of closing the perspiratory tubes. When they are covered by a
coating of varnish impervious to water and gases, death ensues in from six
to twelve hours; the attendant symptoms resembling those of suffocation.
[Sidenote: 19. Give the story in relation to the boy covered with gold
foil.]
19. It is related that, at the coronation of one of the Popes about three
hundred years ago, a little boy was chosen to act the part of an angel; and
in order that his appearance might be as gorgeous as possible, he was
covered from head to foot with a coating of gold foil. He was soon taken
sick, and although every known means were employed for his recovery, except
the removal of his fatal golden covering, he died in a few hours.
[Sidenote: 20. Give the quotation. Perspiration?]
20. THE IMPORTANCE OF BATHING.--From these considerations, it is evident
that health must greatly depend upon the free action of the skin. "He who
keeps the skin ruddy and soft, shuts many gates against disease." When the
watery portion of the perspiration evaporates, the solid matter is left
behind on the surface. There, also, remain the scales of the worn-out
cuticle, and the excess of sebaceous matter. In order to secure the natural
action of the skin, these impurities require to be removed by the frequent
application of water.
[Sidenote: 21. Ablution in warm climates? What advice is given?]
21. In warm climates, and during hot weather, ablution should be more
frequently practised. For a person in good health, a daily cold bath is
advisable. To this should be added occasionally a tepid bath, with soap,
water alone not being sufficient to remove impurities of a greasy nature.
Soap facilitates this, by forming with such substances a chemical mixture,
which is readily soluble in water, and is by it removed from the body. {48}
[Sidenote: 22. Liebig's maxim? What further is added?]
22. There is a maxim by the chemist Liebig, to the effect, that the
civilization of a nation is high, in proportion to the amount of soap that
it consumes; and that it is low, in proportion to its use of perfumes. In
some degree, we may apply the same test to the refinement of an individual.
The soap removes impurity; the perfume covers, while retaining it.
[Sidenote: 23. What is said about cold bathing?]
23. THE DIFFERENT KINDS OF BATHS.--All persons are not alike able to use
the cold bath. When the health is vigorous, and the system does not feel a
shock after such a bath, a prompt reaction and glow upon the surface will
show that it is beneficial. Where this pleasurable feeling is not
experienced, but rather a chill and sense of depression ensues, we are
warned that the system will not, with impunity, endure cold bathing.
[Sidenote: 24. What is said about warm bathing?]
24. It should also be borne in mind, that the warm or hot bath cannot be
continued so long, or repeated so frequently as the cold, on account of the
enervating effect of unusual heat so applied to the body. For persons who
are not in robust health, one warm bath each week is sufficient; this class
should be careful to avoid every extreme in reference to bathing, clothing,
and whatever greatly affects the action of the skin.
[Sidenote: 25. What is said about sea-bathing?]
25. Sea-bathing is even more invigorating than fresh-water bathing. Those
who cannot endure the fresh water, are often benefited by the salt-water
baths. This may be accounted for, in part, by the stimulant action upon the
surface, of the saline particles of the sea-water; but the exciting scenes
and circumstances of sea-bathing also exert an important influence. The
open-air exercise, the rolling surf, the genial weather, and usually the
cheerful company, add to its intrinsic benefits. {49}
[Sidenote: 26. What is said as to the time and manner of bathing?]
26. TIME AND MANNER OF BATHING.--A person in sound health may take a bath
at almost any time, except directly after a full meal. The most appropriate
time is about three hours after a meal, the noon-hour being probably the
best. For the cold bath, taken rapidly, no time is better than immediately
after rising. Those beginning the use of cold baths should first try them
at 70° Fahr., and gradually use those of a lower temperature. From five to
twenty minutes may be considered the proper limit of time to remain in a
bath; but a sensation of chilliness is a signal to withdraw instantly,
whether at home, or at the sea-side. Two sea-baths may be taken daily; one
of any other kind is sufficient.
[Sidenote: 27. Condition of the body when bathing? Direction, after
bathing?]
27. The body should be warm, rather than cold, when stepping into the bath;
and after it, the skin should be thoroughly dried with a coarse towel. It
is best to continue friction until there is a sensation of warmth or "glow"
throughout the entire surface. This reaction is the test of the good
effects of the bath. If reaction is still incomplete, a short walk may be
taken, especially in the sunshine. It is very congenial, however, both to
health and comfort, to rest for a short time directly after bathing, or to
take some light refreshment. This is better than severe exercise or a full
meal.
[Sidenote: 28. Bathing among the ancients? Baths of Rome?]
28. BATHING AMONG THE ANCIENTS.--The Romans and other nations of antiquity
made great use of the vapor-bath as a means of preserving the health, but
more particularly as a luxury. Their method was not unlike that employed in
northern Europe at the present day. The public baths of Rome and other
cities are among the grandest and most interesting monuments of ancient
luxury and splendor; and from their ruins have been recovered some of the
most beautiful works of art. {50}
[Sidenote: 29. After the bath? Swimming among the ancients?]
29. The Thermæ, as the baths of Rome were called, were of great extent,
built very substantially, and ornamented at vast expense. They were
practically free to all, the cost of a bath having been less than a cent.
It is related that some persons bathed seven times a day. After the bath
their bodies were anointed with perfumed oil. If the weather was fine, they
passed directly from the Thermæ into the gymnasium, and engaged in some
gentle exercise previous to taking the midday meal. Between two and three
in the afternoon was the favorite hour for this ancient luxury. Swimming
was a favorite exercise, and a knowledge of it was regarded as necessary to
every educated man. Their common expression, when speaking of an ignorant
person, was, "He can neither read nor swim."
[Sidenote: 30. The Sun-bath? The story of Pliny?]
30. THE SUN-BATH.--Some also were accustomed daily to anoint themselves,
and lie or walk in apartments arranged for the purpose, with naked bodies
exposed to the direct rays of the sun. There is an interesting allusion to
this practice, in a letter of the younger Pliny to the historian Tacitus,
describing the destruction of Pompeii by an eruption of Vesuvius. "My
uncle," (Pliny the elder,) "was at that time in command of the fleet at
Misenum. On the 24th of August, about one in the afternoon, my mother
desired him to notice a cloud which seemed of unusual shape and dimensions.
He had just returned from _taking the benefit of the sun_, and after a cold
bath, and a slight repast, had retired to his study." Then follows a
description of the destruction of Pompeii, and the death of the elder
Pliny.
[Sidenote: 31. Benefit of the sun? Effect upon plants? Skin?]
31. We may judge somewhat of "the benefits of the sun," by observing the
unnatural and undeveloped condition of plants and animals which are
deprived of light. Plants become blanched and tender; the fish of {51}
subterranean lakes, where no light enters, are undersized, and have no
eyes; tadpoles kept in the dark do not develop into frogs; men growing up
in mines are sallow, pale, and deformed. Besides the well-known effect of
solar light in tanning the skin, it also makes it thicker and better able
to resist exposure; though the complexion may be thereby injured, the
health gains more than compensate for the loss of beauty. "To make good
the loss of the lily, where the sun has cast his ray, he seldom fails to
plant the rose."
[Sidenote: 32. Direction about clothing? Exposing limbs of children?
Clothing, night and day?]
32. CLOTHING.--In reference to clothing, we are far more apt, in our
changeful climate, to use too little than too much. An aphorism of
Boerhaave, worth remembering, if not of adopting, is, "We should put off
our winter clothing on midsummer's day, and put it on again the day after."
He also says, "Only fools and beggars suffer from the cold; the latter not
being able to get sufficient clothes, the others not having the sense to
wear them." The practice of exposing the limbs and necks of young children,
for the alleged purpose of "hardening" them, is quite hazardous. It is not
to be denied that some seem to be made tough by the process; but it is so
only with the rugged children, the delicate ones will invariably suffer
under this fanciful treatment. As has been stated before, the skin is
constantly acting, by night as well as by day. It is therefore conducive
both to cleanliness and comfort to change entirely the clothing on retiring
for the night. The day-clothing should be aired during the night, and the
bedding should be aired in the morning, for the same reason.
[Sidenote: 33. Cosmetics? Painters' colic?]
33. POISONOUS COSMETICS.--The extensive use of _cosmetics_ for the
complexion is a fertile source of disease. The majority of these
preparations contain certain poisonous mineral substances, chiefly lead.
Now, the skin rapidly absorbs the fine particles of lead, and the system
{52} experiences the same evil effects that are observed among the
operatives in lead works and painters, namely, "painters' colic," and
paralysis of the hands, called "wrist-drop."
34. Certain hair-dyes also contain lead, together with other noxious and
filthy ingredients. These do not work as great harm as the cosmetics, since
they are purposely kept away from the skin, but they rob the hair of its
vitality. Eye-washes, too, are made from solutions of lead, and many an eye
has been ruined by their use. They deposit a white metallic scale on the
surface of the eye, which becomes a permanent obstruction to the vision.
QUESTIONS FOR TOPICAL REVIEW.
PAGE
1. What are the characteristics of the skin, and what office
does it perform? 41
2. What can you state of the structure of the skin? 41
3. Describe the cuticle and tell its use. 41, 42
4. Describe the cutis or true skin and tell its use. 42
5. What can you state of the nature and growth of the nail? 42, 43
6. Of the nature and growth of the hair? 42, 43, 44
7. Of the offices performed by the nails and hair? 44
8. How is the difference in complexion in different persons
accounted for? 44
9. How is the presence of freckles accounted for? 44
10. How does Nature provide a dressing for the hair? 44, 45
11. What other service do the sebaceous glands perform? 45
12. State what you can of the perspiratory glands. 45
13. What is the difference between sensible and insensible
perspiration? 46
14. State the uses and importance of perspiration. 46, 47
15. What impurities gather naturally on the skin? 47
16. Repeat what is said of the importance of bathing. 47, 48
17. When should we indulge in cold, warm, and sea bathing? 48, 49
18. What is the effect in each case? 48
19. What directions are given as to the time and manner for
bathing? 49
20. What is related of bathing among the ancients? 49, 50
21. What is related to show the antiquity of sun-bathing? 50
22. What are the effects of sun-bathing? 50, 51
23. What directions are given in relation to clothing the body? 51
24. What can you state of poisonous cosmetics? 51, 52
25. Of hair-dyes and eye-washes? 52
* * * * *
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