One said he wondered that lether was not dearer than any other thing.
Being demanded a reason: because, saith he, it is more stood upon than
any other thing in the world.--_Hazlitt._
What! is the jay more precious than the lark,
Because his feathers are more beautiful?
Or is the adder better than the eel,
Because his painted skin contents the eye?
--_Shakespeare._
A gilded live pig is a sight rarely seen. The rarity of putting gold
leaf all over a living animal of any kind comes from the fact that the
animal dies so soon after the operation. It has been tried several
times and always with the same result.
The idea arose from an experiment unfortunately performed upon a child
on the accession of Leo X. to the papal chair. The child was gilded all
over to represent the Golden Age. The people of Florence were delighted
with the idea, but the death of the child took place so quickly that
some thought the brief duration of the Golden Age was miraculously
represented as well as its great glory.
The experiment has never been repeated upon a human subject, but men of
science cautiously tried to find out the secret of the child's living
but a few hours after the operation, and so gilded pigs and varnished
rabbits and other small animals. From such tests of the value of an
open skin to animal life they found that all things that have breath
must have open skin pores in order to maintain life.
Closing the pores of the skin causes the temperature to fall directly
and the heart and lungs become gorged with blood. The circulation of
the blood is seriously interfered with and death follows with the usual
symptoms of asphyxiation.
Strange as it seemed to those who first witnessed such experiments,
the life of an animal is more directly dependent upon the action of
the skin than upon that of the stomach, the liver, or even the brain.
Monstrosities have been born without brains; but they have frequently
lived for some time, taking their food regularly and having the
appearance of as much comfort as others of their kind with brains. They
died early, but their life was uniformly longer than the time which
elapsed after the application of a coating which stopped the skin of
other animals until death ensued.
A man will live much longer without stomach action than without the
proper functions of the skin. In fact, the skin may take the place of
the stomach in sustaining life for awhile, where the act of swallowing
has been prevented by disease or accident. Feeding the patient through
the skin has been accomplished with varying degrees of success. A bath
of warm water or milk and water assuages thirst. Sailors deprived of
fresh water wet their clothes with salt water, and the absorption of
moisture sustains them where salt water taken into the stomach might
have resulted fatally.
The health of the skin is closely connected with that of the whole
system. Its appearance and condition as to moisture and dryness, as
well as its temperature and color are regularly examined when the
system is out of order. Since the skin is so important to the general
health and its condition is placed so completely within our control, it
is wise to care for it judiciously. We often find other organs of the
body in an unsound condition and begin to doctor them when the whole
trouble has arisen from bad treatment of the skin. The skin needs more
care than the liver or the stomach, and many of the troubles laid at
the door of one or both these organs may be avoided by proper care of
the one organ over which we have entire control, the skin. Where the
skin is prevented from doing its proper work other organs try to carry
it on, and the result is that those organs which are really beyond our
control, and which will work properly without any attention from us,
become diseased by our bad treatment of the organ that comes first in
the natural order of attention.
The skin throws off waste matter from the system. Two and one-half
pounds of watery vapor is poured out daily from the average man. A
clogged skin retains certain salts in the system supposed to have
something to do with such diseases as rheumatism and gout if left in
the blood by too little exercise of perspiration.
Besides the sweat glands there are glands which exude fatty substances
upon the skin, keeping it suitably lubricated and somewhat impervious
to water. In some animals this secretion is so abundant that the skin
cannot become wet in swimming. Beneath the skin are frequently cushions
of fat to protect the soles of the feet and the outside of the larger
joints. The blubber of the whale, the thickest skinned of all animals,
is of this sort, and is evidently intended to make his tremendous
weight less destructive when brought in contact with other objects. The
hide of the swifter ones is peculiarly fitted with large papillæ of
feeling which are supposed to warn them of the presence of rocks and
other objects by the action of the water while swimming near them.
Insects, not having lungs, receive air into their bodies through holes
in the skin. These are called spiracles. They are so protected by hairs
within the holes that water will not enter them. This is why it is
so difficult to drown an insect. But if you touch the abdomen of one
of these skin-breathing creatures, for instance the yellow part of a
wasp, with a drop of oil, the minute openings become almost immediately
clogged and the insect falls dead as if choked completely.
The skin consists of two layers, both of which are exceedingly
interesting. The outer or scarf skin is called the cuticle on the
outside of the body, while wherever the skin dips into the body it is
modified into what is called mucous membrane. This outer skin is not
what is rubbed off the surface in a Turkish bath manipulation or what
is brought off by the rubbing one gives the body with a rough towel.
These rubbings bring off merely the dead outer surface of the cuticle
which should be out of the way because no longer useful. In man it
continually wears off, in serpents it is shed annually in one slough.
The cuticle is the portion of the covering of the body which may best
be noticed when a blister has been raised in the skin. The blister is
an accumulation of fluid between the cuticle and the true skin.
The cuticle, or epidermis, is modified in many other ways than the one
in which it becomes mucous membrane. Where the habits of the animal
make warmth desirable the epidermis dips into the skin and without any
break in its connection rises in the form of wool, which covers the
body of the sheep so effectually. Where the animal is designed for
flight there is the same characteristic dip into the material of the
body, and out of the little sac so formed rises the feather which gives
the bird its beauty and powers of flight. The feather is a modification
of the scarf skin.
Where protection is needed for the body beneath the surface of the
water this changeable substance covers the true skin with hard scales
that make the friction of the water as slight as possible, while
giving a firm and light resisting surface to prevent wounds. Horns and
hoofs are modifications of the scarf skin. Where claws or talons are
needed in the business of fighting or tearing food in bits or digging
holes in the ground or elsewhere, the scarf skin changes itself at the
extremities of paws and feet and produces nails, talons, and claws,
whose powers are both marvelous and varied. For the protection of
most mammals the whole of the body is favored by this power of the
scarf skin to produce whatever seems necessary for the comfort of the
individual, and the body is indented with innumerable minute holes
called hair follicles into which the scarf skin dips and rises again
to the surface transformed into hairs of varying degrees of fineness
and color, beautifully arranged in order, and all pointing in such
directions as will add to the beauty or comfort or terrifying aspect of
the animal.
Not only are our hairs numbered, but each particular hair is furnished
with a little individual muscle of its own running from the base of
the follicle to the inner surface of the true skin, so that when the
proper occasion arises for erection of that individual hair the muscle
contracts apparently of its own accord, and up stands the hair along
with its fellows, ready to frighten the animal that dares to approach
in hostile attitude the owner of the precious coat. Similar muscles
erect the feathers of the owl, and the gorgeous tail of the peacock
dazzles us in the sunlight moved in like manner, while to those more
powerful dermal appendages, the claws, talons, and nails, are attached
more powerful muscles still, with proper nerve connections for the most
effective use of the weapons nature has formed out of the soft outer
skin, which is usually so mild and yielding as to have earned the name
of scarf skin.
This outer skin is formed of cells, flat on the surface, but near the
true skin where they originate, rounded and in many cases even tall and
apparently reaching out towards the surface. It gives the color to the
person by means of pigment cells which lie in its midst.
The black man is dark because of the abundance of pigment cells in his
scarf skin. The albino is light because of their absence. The colors
of hair and feathers are due to these cells in their receptacles, but
white and iridescent feathers are doubtless so partly because of their
absence and partly because of hollow spaces which catch and reflect or
refract the light.
This arrangement of cells into scarf skin has much to do with the
healing of wounds. In cases of old sores that refuse to heal, or where
the skin has been extensively destroyed, the doctors have found that
good, healthy skin may be grafted upon the sores in such a manner as
to invigorate and perfect the process of healing. Small particles of
fresh skin taken from a healthy subject or from some other part of the
patient's body are placed upon the sore, the portions used being about
the size of a small pinhead, and new life seems transplanted in the
deadened part. The skin of a black man grafted upon that of a white man
shows afterwards no trace of its origin, but becomes the same shade as
that which it adjoins.
Several animals change their tints to correspond with their
surroundings. This subject has been exaggerated by observers of an
imaginative turn of mind, but the fact remains that there is a decided
change in the coloring of certain crabs and shrimps as well as in
soles, chameleons, tree-frogs, and two kinds of horned toads wherever
they are found against any well-defined shade or color. Some have
maintained that man takes on a tint somewhat resembling the soil of
the territory where he abides in an uncivilized condition, but Beddard
considers Schweinfurth's statement that the Bongos have a reddish-brown
skin similar to the soil of their country, and the Dinhas, their
neighbors, are as black as their alluvial ground, merely as an account
of what is purely accidental in the instances given.
The coloring of most fish so that they cannot readily be seen by
looking down into the water because of the blackness of their backs,
is highly protective. And the fact is more apparent when we note that
an enemy looking at the same fish from below is hindered in discovery
because the white under parts of the fish are hard to distinguish
against the light of the sky above. Nearly all the protective color
markings of animals are modifications of the scarf skin.
The true skin is of great interest both because it is the seat of what
is called the sense of touch and because it is used so extensively in
the arts in the form of leather.
Nerves of sensation expand over the whole surface of the body, and
their minute branchings in the skin make contact with other substances
highly discernible. But the sense of touch is peculiarly developed in
few of the lower animals, and we may almost regard it as an attribute
of man alone. Our ability to turn our fingers about things and move
our hands over their surface gives us a power that is rare in nature.
We can tell whether things are hot or cold, rough or smooth, sharp or
blunt, wet or dry, and gather many other items of interest which the
other senses are incapable of compassing.
A monkey can wind his tail about a nut and tell by the sense of touch
whether it is worth his while to crack it. The elephant moves the tips
of his trunk carefully over the surface of what he wishes to examine
and gets knowledge he can depend upon. But it is the hand of man that
shows the highest order of development of touch. By it blind men know
their friends and read their books, bank clerks detect the qualities
of the notes they handle, and a thousand deft acts in the arts are
accomplished.
The true skin is covered with minute projections called papillæ. They
may be traced in the palm by the ridges of the scarf skin. They are
arranged there in rows so that while the naked eye does not discern
the projections individually the rows of them may be noticed on the
surface of the scarf skin. Some of these papillæ contain blood vessels
and others corpuscles of touch. Some papillæ are small and simple,
others compound. In one square inch of the palm have been counted
8,100 compound and 20,000 smaller papillæ arranged in regular rows.
There seem to be different end organs for different sensations. There
are different spots which may be touched with a fine pointed pencil
of copper which is quite hot and no feeling will result. Perhaps the
same identical spots touched by the same point, after having been
immersed in ice water, will give sensations of cold. Hot spots and cold
spots may be found and marked upon the skin. There are more hot spots
than cold ones. Either of these when disturbed electrically will give
sensations of heat or cold when neither heat nor cold is applied.
Ashe mentions an experiment which shows that the body is not equipped
exactly alike on both sides, for when both hands are placed in hot
water the heat seems greater to the left than to the right hand.
Aristotle wrote of the peculiar feeling produced by placing the ends
of the first and second fingers upon a small substance like a pea.
With the fingers in their natural position you feel one small round
body. Place the same fingers upon the same pea, but with one finger
crossed over the other so as to touch the pea on the other side, and
you distinctly feel two peas. Another of the freaks of touch may easily
be tried by placing the palms together so that fingers and thumbs are
against their fellows. Close the hands partly and open them again
repeatedly and in a short time instead of each finger's feeling another
finger there will seem to be an oiled pane of glass between the hands
keeping the fingers about a quarter of an inch apart. The delusion
subsides when you look at your hands.
Leather was very early known in Egypt and Greece, and the thongs of
manufactured hides were used by all nations for ropes, harness, and
other instruments. The renowned Gordian knot, 330 B. C., was of leather
thongs. A leather cannon was made in Edinburgh at the time of the
American revolution. Although it was fired three times and found to
answer, and other firearms were made of this material, it never became
common. Had it not been for Mother Goose the leather gun might have
dropped from the memory of man.
Leather is made from the true skin and tannic acid. The processes of
tanning have recently undergone such changes and improvements that it
is out of the question to follow them briefly. The union of the white
fibres of gelatin, gluten, and kindred substances with the tannic acid,
forms insoluble compounds which have great resistance and strength.
This acid is found in oak and hemlock bark, and also in that of many
other trees such as willow, ash, larch, sumac, and terra japonica. Tea
is one-fourth tannic acid.
Deer skin makes the finer kinds of morocco, while sheep and goat
skin make the grades that are used in book-binding. Seal skin makes a
superior kind of enamelled leather for boots, bags, dressing-cases, and
ornamental articles. Hog skin is so full of oil that it resists the
tannic acid, yet saddles are made from it, and it has other uses. The
French glove makers produce a very good kid glove from rat skin which
can be distinguished from the real article only with a microscope.
The tanner applies the term, skin, to the smaller product taken from
calves, dogs, rats, cats, and small game, reserving the dignified name
of hide for that of the full-grown ox or horse, while the skin from a
two-year-old steer is called a kip.
The highest use of skins is in the form of parchment and vellum on
which are printed and engrossed the most valuable documents prepared by
man.