Hygienic Physiology
by
Joel Dorman Steele
Part 3 out of 7
the "roots of the hair," or "all over." What is the cause of these
changes? The blood is a red and a hot fluid; the skin reddens and grows
hot, because its vessels contain an increased quantity of this red and hot
fluid; and its vessels contain more, because the small arteries suddenly
dilate, the natural moderate contraction of their muscles being superseded
by a state of relaxation. In other words, the action of the nerves which
cause this muscular contraction is suspended. On the other hand, in many
people, extreme terror causes the skin to grow cold, and the face to
appear pale and pinched. Under these circumstances, in fact, the supply of
blood to the skin is greatly diminished, in consequence of an excessive
stimulation of the nerves of the small arteries, which causes them to
contract and so to cut off the supply of blood more or less completely.--
Huxley's _Physiology_.]
2. _Inflammation_ means simply a burning. If there is irritation or
an injury at any spot, the blood sets thither and reddens it. This extra
supply, both by its presence and the friction of the swiftly moving
currents, produces heat. The pressure of the distended vessels upon the
nerves frets them, and produces pain. The swelling stretches the walls of
the blood vessels, and the serum or lymph oozes through. The four
characteristics of an inflammation are redness, heat, pain, and swelling.
3. _Bleeding_, if from an artery, will be of red blood, and will come
in jets; [Footnote: The elasticity of the arteries (p. 114) is a physical
property, as may easily be shown by removing one from a dead body. If they
were rigid and unyielding, a considerable portion of the heart's force
would be uselessly expended against their walls. Their expansion is a
passive state, and depends on the pressure of the blood within them; but
their vital contractility is an active property.--The intermittent
movement of the blood through the arteries is strikingly shown in the
manner in which they bleed when wounded. When an artery is cut across, the
blood spurts out with great force to a distance of several feet, but the
flow is not continuous. It escapes in a series of jets, the long, slender
scarlet stream rising and falling with each beat of the heart, and this
pulsation of the blood stream tells at once that it comes from a wounded
artery. But as the blood traverses these elastic tubes, the abruptness of
the heart's stroke becomes gradually broken and the current equalized, so
that the greater the distance from the heart the less obvious is the
pulsation, until at length in the capillaries the rate of the stream
becomes uniform.] if from the veins, it will be of dark blood, and will
flow in a steady stream. If only a small vessel be severed, it may be
checked by a piece of cloth held or bound firmly upon the wound. If a
large trunk be cut, especially in a limb, make a knot in a handkerchief
and tie it loosely about the limb; then, placing the knot on the limb,
with a short stick twist the handkerchief tightly enough to stop the flow.
If you have a piece of cloth to use as a pad, the knot will be
unnecessary. If it be an artery that is cut, the pressure should be
applied between the wound and the heart; if a vein, beyond the wound. If
you are alone, and are severely wounded, or in an emergency, like a
railroad accident, use the remedy which has saved many a life upon the
battlefield--bind or hold a handful of dry earth upon the wound, elevate
the part, and await surgical assistance.
4. _Scrofula_ is generally inherited. It is a disease affecting the
lymphatic glands, most commonly those of the neck, forming "kernels," as
they are called. It is, however, liable to attack any organ. Persons
inheriting this disease can hope to ward off its insidious approaches only
by the utmost care in diet and exercise; by the use of pure air and warm
clothing, and by avoiding late hours and undue stimulus of all kinds.
Probably the most fatal and common excitants of the latent seeds of
scrofula are insufficient or improper food, and want of ventilation.
5. _A COLD_.--We put on a thinner dress than usual, or, when heated,
sit in a cool place. The skin is chilled, and the perspiration checked.
The blood, no longer cleansed and reduced in volume by the drainage
through the pores, sets to the lungs for purification. That organ is
oppressed, breathing becomes difficult, and the extra mucus secreted by
the irritated surface of the membrane is thrown off by coughing. The
mucous membrane of the nasal chamber sympathizes with the difficulty, and
we have "a cold in the head," or a catarrh. In general, the excess of
blood seeks the weakest point, and develops there any latent disease
[Footnote: A party go out for a walk and are caught in a rain, or, coming
home heated from some close assembly, throw off their coats to enjoy the
deliciously cool breeze. The next day, one has a fever, another a slight
headache, another pleurisy, another pneumonia, another rheumatism, while
some of the number escape without any ill feeling whatever. The last had
vital force sufficient to withstand the disturbance, but in the others
there were various weak points, and to these the excess of blood has gone,
producing congestion.] Where one person has been killed in battle,
thousands have died of colds.
To restore the equipoise must be the object of all treatment. We put the
feet in hot water and they soon become red and gorged with the blood which
is thus called from the congested organs. Hot footbaths have saved
multitudes of lives. It is well in case of a sudden cold to go immediately
to bed, and with hot drinks and extra clothing open the pores, and induce
free perspiration. This calls the blood to the surface, and, by equalizing
and diminishing the volume of the circulation, affords relief. [Footnote:
Severe colds may often be relieved in their first stages by using lemons
freely during the day, and taking at night fifteen or twenty grains of
sodium bromide. Great care, however, should be observed in employing the
latter remedy, except under the advice of a physician.]
6. _Catarrh_ commonly manifests itself by the symptoms known as those
of a "cold in the head," and is produced by the same causes. It is an
inflammation of the mucous membrane lining the nasal and bronchial
passages. One going out from the hot dry air of a furnace-heated room into
the cold damp atmosphere of our climate can hardly avoid irritating and
inflaming this tender membrane. If our rooms were heated less intensely,
and ventilated more thoroughly, so that we had not the present hothouse
sensitiveness to cold air, this disease would be far less universal, and
perhaps would disappear entirely. [Footnote: Dr. Gray gives the following
table:
=====================================================================
Rooms Occupied by Letter-press Printers. | Number | Subject to
| per cent | Catarrh
| Spitting |
| Blood. |
------------------------------------------+------------+-------------
104 men having less than 500 cubic feet | |
of air to breathe | 12.50 | 12.50
| |
115 men having from 500 to 600 cubic feet | |
of air to breathe | 4.35 | 3.58
| |
101 men having more than 600 cubic feet | |
of air to breathe | 3.96 | 1.98
---------------------------------------------------------------------]
(See p. 315.)
ALCOHOLIC DRINKS AND NARCOTICS.
1. ALCOHOL.
That we may understand fully the effect of alcohol upon the human system,
let us first consider its nature and the process by which harmless fruits
and grains are made to produce a substance so unlike themselves in its
deleterious effects.
HOW ALCOHOL IS MADE.--When any substance containing sugar, as fruit juice,
is caused to ferment, the elements of which the sugar is composed, viz.,
hydrogen, carbon, and oxygen, so rearrange themselves as to form carbon
dioxide (carbonic acid), alcohol, and certain volatile oils and ethers.
[Footnote: The precise relation between chemical phenomena and the
physiological functions of the organic ferment is still to be discovered;
and all that has been said, written, and brought forward to decide the
question, need experimental proof.--SCHÜTZENBERGER.] The carbonic acid
partly evaporates and partly remains in the liquor; the alcohol is the
poisonous or intoxicating principle, while the oils and ethers impart the
peculiar flavor and odor. Thus wine is fermented grape juice, and cider is
fermented apple juice, each having its distinctive taste and smell, and
each containing, as one product of fermentation, more or less of the
inebriating alcohol. Wines are also made from other fruits and vegetables,
such as oranges, currants, tomatoes, and rhubarb, but the alcohol which
they contain is of the same nature in all cases, whether the fermented
liquor has been manufactured in great quantities, by large presses, or by
a simple domestic process for home consumption. It is important to
remember this fact, as many people do not associate alcohol with such
beverages as domestic wines and home-brewed ales, whereas it is always
present with the same treacherous qualities which attach to it everywhere.
An apple is a wholesome and useful fruit, and its simple juice, fragrant
and refreshing, is a delight to the palate; but apple juice converted into
cider and allowed to enter upon alcoholic fermentation, loses its
innocence, and becomes a dangerous drink, because it is the nature of the
alcohol it now contains to create an appetite for more alcohol. (See p.
185.)
WHAT IS A FERMENT?--Ferments, of which there are many varieties in nature,
are minute living organisms analogous to the microscopic objects called
bacteria or microbes, [Footnote: There is no well-defined limit between
ferments and bacteria, any more than between ferments and fungi, or again,
between fungi and bacteria. Their smaller size is the principal difference
which separates bacteria from ferments, although there are bacteria of
large size, such as are so frequently found in the mouth of even a healthy
man, and which much resemble in their mode of growth some of the lower
fungi.--Trouessart.] of which we have heard much in late years, especially
in connection with the famous researches and experiments of the great
French investigator, M. Pasteur. He tells us that "Every fermentation has
its specific ferment. This minute being produces the transformation which
constitutes fermentation by breathing the oxygen of the substance to be
fermented, or by appropriating for an instant the whole substance, then
destroying it by what may be termed the secretion of the fermented
products." [Footnote: What we call spontaneous fermentation often occurs,
as when apple juice turns to hard cider by simple exposure to the air.
Science teaches us, however, that this change is always effected by the
action of the busy little ferments which, wandering about, drop into the
liquid, begin their rapid propagation, and, in the act of growing, evolve
the products of the fermentation. "If the above liquids be left only in
contact with air which has been passed through a red-hot platinum tube,
and thus the living sporules destroyed; or if the air be simply filtered
by passing through cotton wool, and the sporules prevented from coming
into the liquid, it is found that these fermentable liquids may be
preserved for any length of time without undergoing the slightest
change."--Roscoe.] The effect, therefore, of fermentation is to change
entirely the character of the substance upon which it acts; hence it is an
error to assume that fermented liquors, as beer, wine, and cider, are safe
drinks because the grains or fruits from which they are produced are
healthful foods.
YEAST is a ferment which causes alcoholic fermentation. It consists of
microscopic plants, which increase by the formation of multitudes of tiny
cells not more than 1/2400 of an inch in diameter. In the brewing of beer
they grow in great abundance, making common brewer's yeast. Ferments or
their spores float in the air ready to enter any fermentable liquid, and
under favorable conditions they multiply with great activity and energy.
The favorable conditions include the presence of oxygen or sugar;
[Footnote: Yeast, like ordinary plants, buds and multiplies even in the
absence of fermentable sugar, when it is furnished with free oxygen. This
multiplication, however, is favored by the presence of sugar, which is a
more appropriate element than non-fermentable hydrocarbon compounds. Yeast
is also able to bud and multiply in the absence of free oxygen, but in
this case a fermentable substance is indispensable.--SCHÜTZENBERGER'S
_Fermentation_.] oxygen being, as we know, necessary for the
development and the reproduction of all cell life (p. 107), and ferments
having the power to resolve sugar, which penetrates by endosmose into the
interior of the cell, into alcohol, carbonic acid, glycerine, succinic
acid, and oxygen.
BEER.--The barley used for making beer is first malted, _i. e._,
sprouted, to turn a part of its starch into sugar. When this process has
gone far enough, it is checked by heating the grain in a kiln until the
germ is destroyed. The malt is then crushed, steeped, and fermented with
hops and yeast. The sugar gradually disappears, alcohol is formed, and
carbonic acid escapes into the air. The beer is then put into casks, where
it undergoes a second, slower fermentation, and the carbonic acid gathers;
when the liquor is drawn, this gas bubbles to the surface, giving to the
beer its sparkling, foamy look.
WINE is generally made from the juice of the grape. The juice, or
_must_, as it is called, is placed in vats in the cellar, where the
low temperature favors a slow fermentation. If all the sugar be converted
into alcohol and carbonic-acid gas, a dry wine will remain; if the
fermentation be checked, a sweet wine will result; and if the wine be
bottled while the change is still going on, a brisk effervescing liquor
like champagne, will be formed. All these are dangerous beverages because
of the alcohol they contain.
DISTILLATION.--Alcohol is so volatile that, by the application of heat, it
can be driven off as a vapor from the fermented liquid in which it has
been produced. Steam and various fragrant substances will accompany it,
and, if they are collected and condensed in a cool receiver, a new and
stronger liquor will be formed, having a distinctive odor.
In this way whiskey is distilled from fermented corn, rye, barley, or
potatoes; the alcohol of commerce is distilled from whiskey; brandy, from
wine; rum, from fermented molasses; and gin, from fermented barley and
rye, afterward distilled with juniper berries.
VARIETIES AND PROPERTIES OF ALCOHOL.--There are several varieties of
alcohol produced from distillation of various substances. Thus Methyl
Alcohol is obtained from the decomposition of hard wood when exposed to
intense heat with little or no oxygen present. It is a light, volatile
liquid, which closely resembles ordinary alcohol in all its properties. It
is used in the manufacture of aniline dyes, in making varnishes, and for
burning in spirit lamps. Amyl Alcohol [Footnote: The odor of amylic
alcohol is sweet, nauseous, and heavy. The sensation of its presence
remains long. In taste it is burning and acrid, and it is itself
practically insoluble in water. When it is diluted with common alcohol it
dissolves freely in water, and gives a soft and rather unctuous flavor, I
may call it a fruity flavor, something like that of ripe pears. Amyl
alcohol, introduced as an adulterant, is an extremely dangerous addition
to ordinary alcohol, in whatever form it is presented. From the quantities
of it imported into this country, it is believed to be employed largely in
the adulteration of wines and spirits.--RICHARDSON.] is the chief
constituent of "fusel oil," found in whiskey distilled from potatoes. It
is often present in common alcohol, giving a slightly unpleasant odor when
it evaporates from the hand. Fusel oil is extremely poisonous and lasting
in its effects, so that when contained in liquors it greatly increases
their destructive and intoxicating properties.
Ethyl Alcohol, which is that which we have described as obtained from
fermentation of fruits and grains, is the ordinary alcohol of commerce. We
have spoken of its volatility. This property permits it to pass into vapor
at 56° Fahr. It boils at 173° Fahr. (Water boils at 212°.) Like Methyl
Alcohol, it burns without smoke and with great heat, [Footnote: Pour a
little alcohol into a saucer and apply an ignited match. The liquid will
suddenly take fire, burning with intense heat, but feeble light. In this
process, alcohol takes up oxygen from the air, forming carbonic-acid gas,
and water.--Hold a red-hot coil of platinum wire in a goblet containing a
few drops of alcohol, and a peculiar odor will be noticed. It denotes the
formation of _aldehyde_--a substance produced in the slow oxidation
of alcohol. Still further oxidized, the alcohol would be changed into
_acetic acid_--the sour principle of vinegar.--Put the white of an
egg--nearly pure albumen--into a cup, and pour upon it some alcohol, or
even strong brandy; the fluid albumen will coagulate, becoming hard and
solid. In this connection, it is well to remember that albumen is
contained in our food, while the brain is largely an albuminous
substance.] and is therefore of much value in the arts. Its great solvent
power over fats and mixed oils renders it a useful agent in many
industrial operations. It is also a powerful antiseptic, and no one who
visits a museum of natural history will be likely to forget the rows of
bottles within which float reptilian and batrachian specimens, preserved
in alcohol.
To alcohol, also, we are indebted for various anæsthetic agents, which,
when not abused (p. 340), are of inestimable value. Thus, if certain
proportions of alcohol and nitric acid be mixed together and heated,
nitrite of amyl, so serviceable in relieving the agonizing spasms peculiar
to that dread disease, angina pectoris, will be obtained. If, instead of
nitric, we use sulphuric acid, we shall get ether; if chlorine be passed
through alcohol, hydrate of chloral is the result; and, if chloride of
lime and alcohol be treated together, the outcome is chloroform.
One of the most striking properties of alcohol, and one which we shall
hereafter consider in its disastrous effects upon the tissues of our body,
is its affinity for water. [Footnote: Suppose, then, a certain measure of
alcohol be taken into the stomach, it will be absorbed there, but,
previous to absorption, it will have to undergo a proper degree of
dilution with water; for there is this peculiarity respecting alcohol when
it is separated by an animal membrane from a watery fluid like the blood,
that it will not pass through the membrane until it has become charged, to
a given point of dilution, with water. Alcohol is itself, in fact, so
greedy for water that it will pick it up from watery textures, and deprive
them of it until, by its saturation, its power of reception is exhausted,
after which it will diffuse into the current of circulating fluid.
To illustrate this fact of dilution I perform a simple experiment. Into a
bladder is placed a mixture consisting of equal parts of alcohol and
distilled water. Into the neck of the bladder a long glass tube is
inserted and firmly tied. Then the bladder is immersed in a saline fluid
representing an artificial serum of blood. The result is, that the alcohol
in the bladder absorbs water from the surrounding saline solution, and
thereby a column of fluid passes up into the glass tube. A second mixture
of alcohol and water, in the proportion this time of one part of alcohol
to two of water, is put into another bladder immersed in like manner in an
artificial serum. In this instance a little fluid also passes from the
outside into the bladder, so that there is a rise of water in the tube,
but less than in the previous instance. A third mixture, consisting of one
part of alcohol with three parts of water, is placed in another little
bladder, and is also suspended in the artificial serum. In this case there
is, for a time, a small rise of fluid in the tube connected with the
bladder; but after a while, owing to the dilution which took place, a
current from within outward sets in, and the tube becomes empty. Thus each
bladder charged originally with the same quantity of fluid contains at
last a different quantity. The first contains more than it did originally,
the second only a little more, the third a little less. From the third,
absorption takes place, and if I keep changing and replacing the outer
fluid which surrounds the bladder with fresh serum, I can in time, owing
to the double current of water into the bladder through its coats, and of
water and alcohol out of the bladder into the serum, remove all the
alcohol. In this way it is removed from the stomach into the circulating
blood after it has been swallowed. When we dilute alcohol with water
before drinking it, we quicken its absorption. If we do not dilute it
sufficiently, it is diluted in the stomach by transudation of water in the
stomach, until the required reduction for its absorption; the current then
sets in toward the blood, and passes into the circulating canals by the
veins.--RICHARDSON.] When strong alcohol is exposed to the air, it absorbs
moisture and becomes diluted; at the same time, the spirit itself
evaporates. The commercial or proof spirit is about one half water; the
strongest holds five per cent; and to obtain absolute or waterless
alcohol, requires careful distillation in connection with some substance,
as lime, that has a still greater affinity for water, and so can despoil
the alcohol.
ALCOHOL IN ITS DESTRUCTIVE RELATION TO PLANT AND ANIMAL LIFE.--If we pour
a little quantity of strong spirits upon a growing plant in our garden or
conservatory, we shall soon see it shrivel and die. If we apply it to
insects or small reptiles which we may have captured for specimens in our
cabinet, the same potent poison will procure for them a speedy death. If
we force one of our domestic animals to take habitual doses of it, the
animal will not only strongly protest against the unnatural and nauseous
potion, but it will gradually sicken and lose all power for usefulness.
"If I wished," says a distinguished English physician, "by scientific
experiment to spoil for work the most perfect specimen of a working
animal, say a horse, without inflicting mechanical injury, I could choose
no better agent for the purpose of the experiment than alcohol."
[Footnote: "The effects produced by alcohol are common, so far as I can
discover, to every animal. Alcohol is a universal intoxicant, and in the
higher orders of animals is capable of inducing the most systematic
phenomena of disease. But it is reserved for man himself to exhibit these
phenomena in their purest form, and to present, through them, in the
morbid conditions belonging to his age, a distinct pathology. Bad as this
is, it might be worse; for if the evils of alcohol were made to extend
equally to animals lower than man, we should soon have none that were
tamable, none that were workable, and none that were eatable."]
ALCOHOL IN WINE, BEER, AND CIDER IDENTICAL WITH ALCOHOL IN ARDENT
SPIRITS.--In all liquors the active principle is alcohol. It comprises
from six to eight per cent of ale and porter, seven to seventeen per cent
of wine, and forty to fifty per cent of brandy and whiskey. All these may
therefore be considered as alcohol more or less diluted with water and
flavored with various aromatics. The taste of different liquors--as
brandy, gin, beer, cider, etc.--may vary greatly, but they all produce
certain physiological effects, due to their common ingredient--alcohol.
"In whatever form it enters," says Dr. Richardson, "whether as spirit,
wine, or ale, matters little when its specific influence is kept steadily
in view. To say this man only drinks ale, that man only drinks wine, while
a third drinks spirits, is merely to say, when the apology is unclothed,
that all drink the same danger." In other words, the poisonous nature of
alcohol, and the effects which result when it is taken into the stomach,
are definite and immutable facts, which are not dependent upon any
particular name or disguise under which the poison finds entrance.
We shall learn, as we study the influence of alcohol upon the human
system, that one of its most subtle characteristics is the progressive
appetite for itself (p. 185) which it induces, an appetite which, in many
cases, is formed long before its unhappy subject is aware of his danger.
The intelligent pupil, who knows how to reason from cause to effect, needs
hardly to be told, in view of this physical truth, of the peril that lies
in the first draught of _any_ fermented liquor, even though it be so
seemingly harmless as a glass of home-brewed beer or "slightly-beaded"
cider. Few of us really understand our own inherent weakness or the
hereditary proclivities (p. 186) that may be lurking in our blood, ready
to master us when opportunity invites; but we may be tolerably certain
that if we resolutely refuse to tamper with cider, beer, or wine, we shall
not fall into temptation before rum, gin, or brandy. Since we know that in
all fermented beverages there is present the same treacherous element,
alcohol, we are truly wise only when we decline to measure arms in any way
with an enemy so seductive in its advances, so insidious in its influence,
and so terrible in its triumph. [Footnote: Aside from all considerations
of physical, mental, and moral injury wrought by the use of alcoholic
drinks, every young man may well take into account the damaging effect of
such a dangerous habit upon his business prospects. Careful business men
are becoming more and more unwilling to take into their employ any person
addicted to liquor drinking. Within the past few years the officers of
several railroads, having found that a considerable portion of their
losses could be directly traced to the drinking habits of some one or more
of their employés, have ordered the dismissal of all persons in their
service who were known to use intoxicants, with the additional provision
that persons thus discharged should never be reinstated. Many Eastern
manufactories have adopted similar rules. All mercantile agencies now
report the habits of business men in this respect, and some life insurance
companies refuse to insure habitual drinkers, regarding such risks as
"extra-hazardous."]
Let us now consider the physiological effects of alcohol upon the organs
immediately connected with the circulation of the blood.
GENERAL EFFECT OF ALCOHOL UPON THE CIRCULATION.--During the experiment
described on page 118, the influence of alcohol upon the blood may be
beautifully tested. Place on the web of the frog's foot a drop of dilute
spirit. The blood vessels immediately expand--an effect known as
"_Vascular enlargement_." Channels before unseen open, and the blood
disks fly along at a brisker rate. Next, touch the membrane with a drop of
pure spirit. The blood channels quickly contract; the cells slacken their
speed; and, finally, all motion ceases. The flesh shrivels up and dies.
The circulation thus stopped is stopped forever. The part affected will in
time slough off. Alcohol has killed it.
The influence of alcohol upon the human system is very similar. When
strong, as in spirits, it acts as an irritant, narcotic poison (p. 142,
note). Diluted, as in fermented liquors, it dilates the blood vessels,
quickens the circulation, hastens the heart throbs, and accelerates the
respiration.
THE EFFECT OF ALCOHOL UPON THE HEART.--What means this rapid flow of the
blood? It shows that the heart is overworking. The nerves that lead to the
minute capillaries and regulate the passage of the vital current through
the extreme parts of the body, are paralyzed by this active narcotic. The
tiny blood vessels at once expand. This "Vascular enlargement" removes the
resistance to the passage of the blood, and a rapid beating of the heart
results. [Footnote: Dr. B. W. Richardson's experiments tend to prove that
this apparently stimulating action of alcohol upon the heart is due to the
paralysis of the nerves that control the capillaries (Note, p. 208), which
ordinarily check the flow of the blood (p. 117). The heart, like other
muscles under the influence of alcohol, really loses power, and contracts
less vigorously (p. 183). Dr. Palmer, of the University of Michigan, also
claimed that alcohol, in fact, diminishes the strength of the heart. Prof.
Martin, of Johns Hopkins University, from a series of carefully conducted
experiments upon dogs, concluded that blood containing one fourth per cent
of alcohol almost invariably diminishes within a minute the work done by
the heart; blood containing one half per cent always diminishes it, and
may reduce the amount pumped out by the left ventricle so that it is not
sufficient to supply the coronary arteries. One hundred years ago, alcohol
was always spoken of as a stimulant. Modern experiment and investigation
challenged that definition, and it is now classified as a narcotic. There
are, however, able physicians who maintain that, taken in small doses, and
under certain physical conditions, it has the effect of a stimulant. All
agree that, when taken in any amount, it tends to create an appetite for
more.]
Careful experiments show that two ounces of alcohol--an amount contained
in the daily potations of a very moderate ale or whiskey drinker--increase
the heart beats six thousand in twenty-four hours;--a degree of work
represented by that of lifting up a weight of seven tons to a height of
one foot. Reducing this sum to ounces and dividing, we find that the heart
is driven to do extra work equivalent to lifting seven ounces one foot
high one thousand four hundred and ninety-three times each hour! No wonder
that the drinker feels a reaction, a physical languor, after the earliest
effects of his indulgence have passed away. The heart flags, the brain and
the muscles feel exhausted, and rest and sleep are imperatively demanded.
During this time of excitement, the machinery of life has really been
"running down." "It is hard work," says Richardson, "to fight against
alcohol; harder than rowing, walking, wrestling, coal heaving, or the
treadmill itself."
All this is only the first effect of alcohol upon the heart. Long-
continued use of this disturbing agent causes a "Degeneration of the
muscular fiber," [Footnote: This "Degeneration" of the various tissues of
the body, we shall find, as we proceed, is one of the most marked effects
of alcoholized blood. The change consists in an excess of liquid, or, more
commonly, in a deposit of fat. This fatty matter is not an increase of the
organ, but it takes the place of a part of its fiber, thus weakening the
structure, and reducing the power of the tissue to perform its function.
Almost everywhere in the body we thus find cells--muscle cells, liver
cells, nerve cells, as the case may be--changing one by one, under the
influence of this potent disorganizer, into unhealthy fat cells. "Alcohol
has been well termed," says the _London Lancet_, "the 'Genius of
Degeneration.'"
The cause of this degeneration can be easily explained. The increased
activity of the circulation compels a correspondingly increased activity
of the cell changes: but the essential condition of healthful change--the
presence of additional oxygen--is wanting (see p. 143), and the operation
is imperfectly performed.--BRODIE.] so that the heart loses its old power
to drive the blood, and, after a time, fails to respond even to the spur
of the excitant that has urged it to ruin.
INFLUENCE UPON THE MEMBRANES.--The flush of the face and the bloodshot
eye, that are such noticeable effects of even a small quantity of liquor,
indicate the condition of all the internal organs. The delicate linings of
the stomach, heart, brain, liver, and lungs are reddened, and every tiny
vein is inflamed, like the blushing nose itself. If the use of liquor is
habitual, this "Vascular enlargement," that at first slowly passed away
after each indulgence, becomes permanent, and now the discolored, blotched
skin reveals the state of the entire mucous membrane.
We learned on page 55 what a peculiar office the membrane fills in
nourishing the organs it enwraps. Anything that disturbs its delicate
structure must mar its efficiency. Alcohol has a wonderful affinity for
water. To satisfy this greed, it will absorb moisture from the tissues
with which it comes in contact, as well as from their lubricating juices.
The enlargement of the blood vessels and their permanent congestion must
interfere with the filtering action of the membrane. In time, all the
membranes become dry, thickened, and hardened; they then shrink upon the
sensitive nerve, or stiffen the joint, or enfeeble the muscle. The
function of these membranes being deranged, they will not furnish the
organs with perfected material, and the clogged pores will no longer
filter their natural fluids. Every organ in the body will feel this
change.
EFFECT UPON THE BLOOD. [Footnote: Alcohol acts upon the oxygen carrier,
the coloring matter of the red corpuscles, causing it to settle in one
part of the globule, or even to leave the corpuscle, and deposit itself in
other elements of the blood. Thus the red corpuscle may become colorless,
distorted, shrunken, and even entirely broken up--Dr. G. B. HARRIMAN.]--
From the stomach, alcohol passes directly into the circulation, and so, in
a few minutes, is swept through the entire system. If it be present in
sufficient amount and strength, its eager desire for water will lead it to
absorb moisture from the red corpuscles, causing them to shrink, change
their form, harden, and lose some of their ability to carry oxygen; it may
even make them adhere in masses, and so hinder their passage through the
tiny capillaries.--RICHARDSON.
With most persons who indulge freely in alcoholic drinks, the blood is
thin, the avidity of alcohol for water causing the burning thirst so
familiar to all drinkers, and hence the use of enormous quantities of
water, oftener of beer, which unnaturally dilutes the blood. The blood
then easily flows from a wound, and renders an accident or surgical
operation very dangerous.
When the blood tends, as in other cases of an excessive use of spirits, to
coagulate in the capillaries, [Footnote: The blood is rendered unduly
thin, or is coagulated, according to the amount of alcohol that is carried
into the circulatory system. "The spirit may fix the water with the
fibrin, and thus destroy the power of coagulation; or it may extract the
water so determinately as to produce coagulation. This explains why, in
acute cases of poisoning by alcohol, the blood is sometimes found quite
fluid, at other times firmly coagulated in the vessels."--B. W.
RICHARDSON.]
Reckless persons have sometimes drunk a large quantity of liquor for a
wager, and, as the result of their folly, have died instantly. The whole
of the blood in the heart having coagulated, the circulation was stopped,
and death inevitably ensued.] there is a liability of an obstruction to
the flow of the vital current through the heart, liver, lungs, etc., that
may cause disease, and in the brain may lay the foundation of paralysis,
or, in extreme cases, of apoplexy.
Wherever the alcoholized blood goes through the body, it bathes the
delicate cells with an irritating narcotic poison, instead of a bland,
nutritious substance.
EFFECT UPON THE LUNGS.--Here we can see how certainly the presence of
alcohol interferes with the red corpuscles in their task of carrying
oxygen. "Even so small a quantity as one part of alcohol to five hundred
of the blood will materially check the absorption of oxygen in the lungs."
The cells, unable to take up oxygen, retain their carbonic-acid gas, and
so return from the lungs, carrying back, to poison the system, the refuse
matter the body has sought to throw off. Thus the lungs no longer furnish
properly oxygenized blood.
The rapid stroke of the heart, already spoken of, is followed by a
corresponding quickening of the respiration. The flush of the cheek is
repeated in the reddened mucous membrane lining the lungs.
When this "Vascular enlargement" becomes permanent, and the highly
albuminous membrane of the air cells is hardened and thickened as well as
congested, the Osmose of the gases to and fro through its pores can no
longer be prompt and free as before. Even when the effect passes off in a
few days after the occasional indulgence, there has been, during that
time, a diminished supply of the life-giving oxygen furnished to the
system; weakness follows, and, in the case of hard drinkers, there is a
marked liability to epidemics. [Footnote: There is no doubt that alcohol
alters and impairs tissues so that they are more prone to disease.--DR. G.
K. SABINE. A volume of statistics could be filled with quotations like the
following: "Mr. Huber, who saw in one town in Russia two thousand one
hundred and sixty persons perish with the cholera in twenty days, said:
'It is a most remarkable circumstance that persons given to drink have
been swept away like flies. In Tiflis, with twenty thousand inhabitants,
every drunkard has fallen,--all are dead, not one remaining.'"]
Physicians tell us, also, that there is a peculiar form of consumption
known as Alcoholic Phthisis caused by long-continued and excessive use of
liquor. It generally attacks those whose splendid physique has enabled
them to "drink deep" with apparent impunity. This type of consumption
appears late in life and is considered incurable. Severe cases of
pneumonia are also generally fatal with inebriates. [Footnote: The
Influence of Alcohol is continued in the chapter on Digestion.]
PRACTICAL QUESTIONS.
1. Why does a dry, cold atmosphere favorably affect catarrh?
2. Why should we put on extra covering when we lie down to sleep?
3. Is it well to throw off our coats or shawls when we come in heated from
a long walk?
4. Why are close-fitting collars or neckties injurious?
5. Which side of the heart is the more liable to inflammation?
6. What gives the toper his red nose?
7. Why does not the arm die when the surgeon ties the principal artery
leading to it?
8. When a fowl is angry, why does its comb redden?
9. Why does a fat man endure cold better than a lean one?
10. Why does one become thin, during a long sickness?
11. What would you do if you should come home "wet to the skin"?
12. When the cold air strikes the face, why does it first blanch and then
flush?
13. What must be the effect of tight lacing upon the circulation of the
blood?
14. Do you know the position of the large arteries in the limbs, so that
in case of accident you could stop the flow of blood?
15. When a person is said to be good-hearted, is it a physical truth?
16. Why does a hot footbath relieve the headache?
17. Why does the body of a drowned or strangled person turn blue?
18. What are the little "kernels" in the armpits?
19. When we are excessively warm, would the thermometer show any rise of
temperature in the body?
20. What forces besides that of the heart aid in propelling the blood?
21. Why can the pulse be best felt in the wrist?
22. Why are starving people exceedingly sensitive to any jar?
23. Why will friction, an application of horse-radish leaves, or a blister
relieve internal congestion?
24. Why are students very liable to cold feet?
25. Is the proverb that "blood is thicker than water" literally true?
26. What is the effect upon the circulation of "holding the breath"?
27. Which side of the heart is the stronger?
28. How is the heart itself nourished? [Footnote: The coronary artery,
springing from the aorta just after its origin, carries blood to the
muscular walls of the heart; the venous blood comes back through the
coronary veins, and empties directly into the right auricle.]
29. Does any venous blood reach the heart without coming through the venæ
cavæ?
30. What would you do, in the absence of a surgeon, in the case of a
severe wound? (See p. 258.)
31. What would you do in the case of a fever? (See p. 263.)
32. What is the most injurious effect of alcohol upon the blood?
33. Are our bodies the same from day to day?
34. Show how life comes by death.
35. Is not the truth just stated as applicable to moral and intellectual,
as to physical life?
36. What vein begins and ends with capillaries? _Ans_. The portal
vein commences with capillaries in the digestive organs, and ends with the
same kind of vessels in the liver. (See p. 166.)
37. By what process is alcohol always formed? Does it exist in nature?
38. What percentage of alcohol is contained in the different kinds of
liquor?
39. Does cider possess the same intoxicating principle as brandy?
40. Describe the general properties of alcohol.
41. Show that alcohol is a narcotic poison.
42. If alcohol is not a stimulant, how does it cause the heart to
overwork?
43. Why is the skin of a drunkard always red and blotched?
44. What danger is there in occasionally using alcoholic drinks?
45. What is meant by a fatty degeneration of the heart?
46. What keeps the blood in circulation between the beats of the heart?
47. What is the office of the capillaries? (See note, p. 373.)
48. Does alcohol interfere with this function?
49. How does alcohol interfere with the regular office of the membranes?
50. How does it check the process of oxidation?
VI.
DIGESTION AND FOOD.
"A man puts some ashes in a hill of corn and thereby doubles its yield.
Then he says, 'My ashes have I turned into corn.' Weak from his labor, he
eats of his corn, and new life comes to him. Again, he says, 'I have
changed my corn into a man.' This also he feels to be the truth.
"It is the problem of the body, remember, that we are discussing. A man is
more than the body; to confound the body and the man is worse than
confounding the body and the clothing."--JOHN DARBY.
ANALYSIS OF DIGESTION AND FOOD
_
| 1. WHY WE NEED FOOD.
|
| 2. WHAT FOOD DOES.
| _ _
| | 1. Nitrogenous. |_a. _The Sugars._
| 3. KINDS OF FOOD....| 2. Carbonaceous....|_b. _The Fats._
| |_3. Minerals
|
| 4. ONE KIND is INSUFFICIENT.
|
| 5. OBJECT OF DIGESTION.
| _
| | --General Description
| | _
| | 1. Mastication and | a. _The Saliva._
| | Insalvation......| b. _Process of
| | |_ Swallowing._
| | _
| | | a. _The Stomach._
| | 2. Gastric | b. _The Gastric
| | Digestion........| Juice._
| | |_c. _The Chyme_
| 6. PROCESSES OF | _
| DIGESTION........| | --Description
| | | a. _The Bile_
| | 3. Intestional | b. _The Pancreatic
| | Digestion........| Juice._
| | | c. _The Small
| | |_ Intestine._
| | _
| | | a. _By the Veins._
| | 4. Absorption.......| b. _By the
| |_ |_ Lacteals._
|
| 7. COMPLEXITY OF THE PROCESS OF DIGESTION.
| _
| | 1. Length of Time required.
| | _
| | | a. _Beef._
| | | b. _Mutton._
| | | c. _Lamb._
| | 2. Value of dif- | d. _Pork._
| | ferent kinds | e. _Fish._
| | of food.........| f. _Milk._
| | | g. _Cheese._
| | |_h. _Eggs, etc._
| | _
| 8. HYGIENE..........| | a. _Coffee._
| | 3. The Stimulants...| b. _Tea._
| | |_C. _Chocolate._
| | 4. Cooking of Food.
| | 5. Rapid Eating.
| | 6. Quantity and Quality of Food.
| | 7. When Food should be taken.
| | 8. How Food should be taken.
| |_9. Need of a Variety
|
| 9. THE WONDERS OF DIGESTION.
| _
| | 1. Dyspepsia.
| 10. DISEASES........|_2. The Mumps.
| _
| | 1. Is Alcohol a Food?
| | 2. Effect upon the Digestion.
| | 3. Effect upon the Liver.
| 11. ALCOHOLIC | 4. Effect upon the Kidneys.
| DRINKS AND | 5. Does Alcohol impart heat?
| NARCOTICS.......| 6. Does Alcohol impart strength?
|_ | 7. The Effect upon the Waste of the Body.
| 8. Alcohol creates a progressive appetite
| for itself.
|_9. Law of Heredity.
DIGESTION AND FOOD.
WHY WE NEED FOOD.--We have learned that our bodies are constantly giving
off waste matter--the products of the fire, or oxidation, as the chemist
terms the change going on within us (Note, p. 107). A man without food
will starve to death in a few days, _i. e._, the oxygen will have
consumed all the available flesh of his body. [Footnote: The stories
current in the newspapers of persons who live for years without food, are,
of course, untrue. The case of the Welsh Fasting Girl, which excited
general interest throughout Great Britain, and was extensively copied in
our own press, is in point. She had succeeded in deceiving not only the
public, but, as some claim, her own parents. At last a strict watch was
set by day and night, precluding the possibility of her receiving any food
except at the hands of the committee, from whom she steadily refused it.
In a few days she died from actual starvation. The youth of the girl, the
apparent honesty of the parents, and the tragical sequel, make it one of
the most remarkable cases of the kind on record.] To replace the daily
outgo, we need about two and a quarter pounds of food, and three pints of
drink. [Footnote: Every cell in the tissues is full of matter ready to set
free at call its stored-up energy--derived from the meat, bread, and
vegetables we have eaten. This energy will pass off quietly when the
organs are in comparative rest, but violently when the muscles contract
with force. When we send an order through a nerve to any part of the body,
a series of tiny explosions run the entire length of the nerve, just as
fire runs through a train of gunpowder. The muscle receives the stimulus,
and, contracting, liberates its energy. The cells of nerve or muscle,
whose contents have thus exploded, as it were, are useless, and must be
carried off by the blood, just as ashes must be swept from the hearth, and
new fuel be supplied to keep up a fire.]
Including the eight hundred pounds of oxygen taken from the air, a man
uses in a year about a ton and a half of material. [Footnote: The
following is the daily ration of a United States soldier. It is said to be
the most generous in the world:
Bread or flour . . . . . . . . . 22 ounces.
Fresh or salt beef (or pork or bacon, 12 oz.) . 20 "
Potatoes (three times per week) . . . . . 16 "
Rice . . . . . . . . . . . 1.6 "
Coffee (or tea, 0.24 oz.) . . . . . . 1.6 "
Sugar . . . . . . . . . . . 2.4 "
Beans . . . . . . . . . . . 0.64 gill.
Vinegar . . . . . . . . . . 0.32 "
Salt . . . . . . . . . . . . 0.16 "]
Yet during this entire time his weight may have been nearly uniform.
[Footnote: If, however, he were kept on the scale pan of a sensitive
balance, he would find that his weight is constantly changing, increasing
with each meal, and then gradually decreasing.] Our bodies are but molds,
in which a certain quantity of matter, checked for a time on its ceaseless
round, receives a definite form. They may be likened, says Huxley, to an
eddy in the river, which retains its shape for a while, yet every instant
each particle of water is changing.
WHAT FOOD DOES.--We make no force ourselves. We can only use that which
nature provides for us. [Footnote: We draw from Nature at once our
substance, and the force by which we operate upon her; being, so far,
parts of her great system, immersed in it for a short time and to a small
extent. Enfolding us, as it were, within her arms, Nature lends us her
forces to expend; we receive them, and pass them on, giving them the
impress of our will, and bending them to our designs, for a little while;
and then--Yes; then it is all one. The great procession pauses not, nor
flags a moment, for our fall. The powers which Nature lent to us she
resumes to herself, or lends, it may be, to another; the use which we have
made of them, or might have made and did not, is written in her book
forever.--_Health and its Conditions_.] All our strength comes from
the food we eat. Food is force--that is, it contains a latent power which
it gives up when it is decomposed. [Footnote: This force is chemical
affinity. It binds together the molecules which compose the food we eat.
When oxygen tears the molecules to pieces and makes them up into smaller
ones, the force is set free. As we shall learn in Physics, it can be
turned, into heat, muscular motion, electricity, etc. The principle that
the different kinds of force can be changed into one another without loss,
is called the Conservation of Energy, and is one of the grandest
discoveries of modern science.--_Popular Physics_, pages 35, 39,
278.] Oxygen is the magic key which unlocks for our use this hidden store.
[Footnote: We have spoken of the mystery that envelops the process of the
conversion of food force into muscular force (note, p. 107). All
physiologists agree that muscular power has its source in the chemical
decomposition of certain substances whereby their potential energy is
released. Probably some of the food undergoes this chemical change before
it passes out of the alimentary canal; possibly some is broken up by the
oxygen while it is being swept along by the blood; but, probably by far
the largest part is converted into the various tissues of the body, and
finally becomes a waste product only after there takes place in the tissue
itself that chemical disorganization that sets free its stored-up power.--
FOSTER'S _Physiology_.] Putting food into our bodies is like placing
a tense spring within a watch; every motion of the body is only a new
direction given to this food force, as every movement of the hand on the
dial is but the manifestation of the power of the bent spring in the
watch. We use the pent-up energies of meat, bread, and vegetables which
are placed at our service, and transfer them to a higher theater of
action. [Footnote: It is a grand thought that we can thus transform what
is common and gross into the refined and spiritual; that out of waving
wheat, wasting flesh, running water, and dead minerals, we can realize the
glorious possibilities of human life.]
KINDS OF FOOD NEEDED.--From what has been said it is clear that, in order
to produce heat and force, we need something that will burn, _i. e._,
with which oxygen can combine. Experiment has proved that to build up
every organ, and keep the body in the best condition, we require three
kinds of food.
1. _Nitrogenous Food_.--As nitrogen is a prominent constituent of the
tissues of the body, food which contains it is therefore necessary to
their growth and repair. [Footnote: Since this kind of food closely
resembles albumen, it is sometimes called _Albuminous_. The term
Proteid is also used.] The most common forms are whites of eggs--which are
nearly pure albumen; casein--the chief constituent of cheese; lean meat;
and gluten--the viscid substance which gives tenacity to dough. Bodies
having a great deal of nitrogen readily oxidize. Hence the peculiar
character of the quick-changing, force-exciting muscle.
2. _Carbonaceous Food_--_i. e._, food containing much carbon--
consists of two kinds, viz., the _sugars_, and the _fats_.
(1) The _sugars_ contain hydrogen and oxygen in the proportion to
form water, and about the same amount of carbon. They may, therefore, be
considered as water, with carbon diffused through it. In digestion, starch
and gum are changed to sugar, and so are ranked with this class.
(2) The _fats_ are like the sugars in composition, but contain less
oxygen, and not in the proportion to form water. They combine with more
oxygen in burning, and so give off more heat.
The non-nitrogenous elements of the food have, however, other uses than to
develop heat. [Footnote: The heat they produce in burning may be turned
into motion of the muscles, according to the principle of the Conservation
of Energy (p. 153, note); while all the structures of the body in their
oxidation develop heat.] Fat is essential to the assimilation of the food,
while sugar and starch aid in digestion and may be converted into fat.
[Footnote: In Turkey, the ladies of the harem are fed on honey and thick
gruel, to make flesh, which is considered to enhance their beauty. The
negroes on the sugar plantations of the South always grow fat during the
sugar-making season.] Fat and carbonaceous material both enter into the
composition of the various tissues, and when, by the breaking up of the
contractile substance of the muscle, their latent energy is set free, they
become the source of muscular force, as well as heat. While the tendency
of the albuminous food is to excite chemical action, and hence the release
of energy, the fats and carbonaceous food may be laid up in the body to
serve as a storehouse of energy to supply future needs.
3. _Mineral Matters_.--Food should contain water, and certain common
minerals, such as iron, [Footnote: While the body can build up a solid
from liquid materials on the one hand, on the other it can pour iron
through its veins and reduce the hardest textures to blood.--HINTON.]
sulphur, magnesia, phosphorus, salt, and potash. About three pints of
water are needed daily to dissolve the food and carry it through the
circulation, to float off waste matter, to lubricate the tissues, and by
evaporation to cool the system (see p. 317). It also enters largely into
the composition of the body. A man weighing one hundred and fifty-four
pounds contains one hundred pounds of water, about twelve gallons--enough,
if rightly arranged, to drown him. [Footnote: It is said that Blumenbach
had a perfect mummy of an adult Teneriffian, which with the viscera
weighed only seven and a half pounds.]
Iron goes to the blood disks; lime combines with phosphoric and carbonic
acids to give solidity to the bones and teeth; phosphorus is essential to
the activity of the brain. Salt is necessary to the secretion of some of
the digestive fluids, and also to aid in working off from the system its
waste products. These various minerals, except iron--sometimes given as a
medicine, and salt--universally used as a condiment, [Footnote: Animals
will travel long distances to obtain salt. Men will barter gold for it;
indeed, among the Gallas and on the coast of Sierra Leone, brothers will
sell their sisters, husbands their wives, and parents their children for
salt. In the district of Accra, on the gold coast of Africa, a handful of
salt is the most valuable thing upon earth after gold, and will purchase a
slave. Mungo Park tells us that with the Mandingoes and Bambaras the use
of salt is such a luxury that to say of a man "he flavors his food with
salt," it is to imply that he is rich; and children will suck a piece of
rock salt as if it were sugar. No stronger mark of respect or affection
can be shown in Muscovy, than the sending of salt from the tables of the
rich to their poorer friends. In the book of Leviticus it is expressly
commanded as one of the ordinances of Moses, that every oblation of meat
upon the altar shall be seasoned with salt, without lacking; and hence it
is called the Salt of the Covenant of God. The Greeks and Romans also used
salt in their sacrificial cakes; and it is still used in the services of
the Latin church--the "_parva mica_" or pinch of salt, being in the
ceremony of baptism, put into the child's mouth, while the priest says,
"Receive the salt of wisdom, and may it be a propitiation to thee for
eternal life." Everywhere and almost always, indeed, it has been regarded
as emblematical of wisdom, wit, and immortality. To taste a man's salt,
was to be bound by the rites of hospitality; and no oath was more solemn
than that which was sworn upon bread and salt. To sprinkle the meat with
salt was to drive away the devil, and to this day, nothing is more unlucky
than to spill the salt.--LETHEBY, _On Food_.] are contained in
small, but sufficient quantities in meat, bread, and vegetables.
ONE KIND OF FOOD IS INSUFFICIENT.--A person fed on starch alone, would
die. It would be a clear case of nitrogen starvation. On the other hand,
as nitrogenous food contains carbon, the elements of water, and various
mineral matters, life could be supported on that alone. But such a
prodigious quantity of lean meat, for example, would be required to
furnish the other elements, that not only would it be very expensive, but
it is likely that after a time the labor of digestion would be too
onerous, and the system would give up the task in despair. The need of a
diet containing both nitrogenous and carbonaceous elements is shown in the
fact that even in the tropical regions oil is relished as a dressing upon
salad. Instinct everywhere suggests the blending. Butter is used with
bread; rice is boiled with milk; cheese is eaten with macaroni, and beans
are baked with pork.
FIG. 45.
[Illustration: _The Stomach and Intestines._ 1, _stomach;_ 2,
_duodenum;_ 3, _small intestine;_ 4, _termination of the
ileum;_ 5, _cœcum;_ 6, _vermiforn appendix;_ 7, _ascending
colon;_ 8, _transverse colon;_ 9, _descending colon;_ 10,
_sigmoid flexure of the colon;_ 11, _rectum;_ 12, _spleen--a
gland whose action is not understood._--LEIDY'S _Anatomy._]
THE OBJECT OF DIGESTION.--If our food were cast directly into the blood,
it could not be used. For example, although the chemist can not see
wherein the albumen of the egg differs from the albumen of the blood, yet
if it be injected into the veins it is unavailable for the purposes
required, and is thrown out again. In the course of digestion the food is
modified in various ways whereby it is fitted for the use of the body,
into which it is finally incorporated. We call this change of food into
flesh _assimilation_, a name for a work done solely by the vital
organs, and so mysterious in its nature that the wisest physiologist gets
only glimpses here and there of its operations.
THE GENERAL PLAN OF DIGESTION.--Nature has provided for this purpose an
entire laboratory, furnished with a chemist's outfit of knives, mortars,
baths, chemicals, filters, etc. The food is (1) chewed, mixed with the
saliva in the mouth, and swallowed; (2) it is acted upon by the gastric
juice in the stomach; (3) it is passed into the intestines, where it
receives the bile, pancreatic juice, and other liquids which completely
dissolve it; [Footnote: Digestion, says Berzelius, is a process of
rinsing. The digestive apparatus secretes, and again absorbs with the food
which it has dissolved, not less than three gallons of liquid per day.--
BARNARD, BIDDER, SCHMIDT, and others.] (4) the nourishing part is absorbed
in the stomach and intestines, and thence thrown into the blood vessels,
whence it is whirled through the body by the torrent of the circulation.
These processes take place within the _alimentary canal_, a narrow
tortuous tube which commences at the mouth, and is about thirty feet long.
[Footnote: The digestive apparatus is lined with mucous membrane that
possesses functions similar to those of the outer skin. It absorbs certain
substances and rejects waste matter. On account of this close connection
between the inner and the outer skin, it is not surprising to find that in
the lowest animals digestion is performed by means of the external skin.
The amœba, which is merely a gelatinous mass, when it takes its food,
extemporizes a stomach for the occasion. It simply wraps itself around the
morsel, and, like an animated apple dumpling with the apple for food and
the crust for animal, goes on with the process until the operation is
completed, when it unrolls itself again and lets the indigestible residue
escape. The common hydra of our brooks can live when turned inside out,
like a glove; either side serving for skin or stomach, as necessity
requires.]
FIG. 46.
[Illustration: _The Parotid--one of the salivary glands._]
I. MASTICATION AND INSALIVATION.--l. _The Saliva_.--The food while
being cut and ground by the teeth is mixed with the saliva. This is a
thin, colorless, frothy, slightly alkaline liquid, secreted [Footnote: By
secretion is meant merely a separation or picking out from the blood.] by
the mucous membrane lining the mouth, and by three pairs of salivary
glands (parotid, submaxillary, and sublingual) opening into the mouth
through ducts, or tubes. The amount varies, but on the average is about
three pounds per day, and in health is always sufficient to keep the mouth
moist. [Footnote: The presence and often the thought of food will "make
one's mouth water." Fear checks the flow of saliva, and hence the East
Indians sometimes attempt to detect theft by making those who are
suspected chew rice. The person from whom it comes out driest is adjudged
the thief.] It softens and dissolves the food, and thus enables us to get
the flavor or taste of what we eat. It contains a peculiar organic
principle called _ptyalin_, [Footnote: One part of ptyalin will
convert eight thousand parts of starch into sugar.--MIALEE.
The saliva has no chemical action on the fats or the albuminous bodies.
Its frothiness enables it to carry oxygen into the stomach, and this is
thought to be of service. The action of the ptyalin commences with great
promptness, and sugar has been detected, it is said, within half a minute
after the starch was placed in the mouth. The process, however, is not
finished there, but continues after reaching the stomach.--VALENTIN. The
saliva thus prepares a small portion of food for absorption at once, and
so insures at the very beginning of the operation of digestion a supply of
force-producing material for the immediate use of the system.] which,
acting upon the starch of the food, changes it into glucose or grape
sugar.
2. _The Process of Swallowing._--The food thus finely pulverized,
softened, and so lubricated by the viscid saliva as to prevent friction as
it passes over the delicate membranes, is conveyed by the tongue and cheek
to the back of the mouth. The soft palate lifts to close the nasal
opening; the epiglottis shuts down, and along this bridge the food is
borne, without danger of falling into the windpipe or escaping into the
nose. The muscular bands of the throat now seize it and take it beyond our
control. The fibers of the œsophagus contract above, while they are lax
below, and convey the food by a worm-like motion into the stomach.
[Footnote: We can observe the peculiar motion of the œsophagus by watching
a horse's neck when he is drinking.]
II. GASTRIC DIGESTION.--1. _The Stomach_ is an irregular expansion of
the digestive tube. Its shape has been compared to that of a bagpipe. It
holds about three pints, though it is susceptible of some distension. It
is composed of an inner, mucous membrane, which secretes the digestive
fluids; an outer, smooth, well-lubricated serous one, which prevents
friction, and between them a stout, muscular coat. The last consists of
two principal layers of longitudinal and circular fibers. When these
contract, they produce a peculiar churning motion, called the
_peristaltic_ (_peri_, round; _stallein_, to arrange) movement, which
thoroughly mixes the contents of the stomach. At the farther end, the
muscular fibers contract and form a gateway, the _pylorus_ (a gate),
as it is called, which carefully guards the exit, and allows no food
to pass from the stomach until properly prepared. [Footnote: With a
wise discretion, however, it opens for buttons, coins, etc., swallowed
by accident; and when we overload the stomach, it seems to become weary of
constantly denying egress, and, finally, giving up in despair, lets
everything through.]
FIG. 47.
[Illustration: _Diagram of the Digestion of the Food. Notice how the
food is submitted to the action of alkaline, acid, and then alkaline
fluids. (See note, p._ 165.)]
2. _The Gastric Juice_.--The lining of the stomach is soft, velvety,
and of a pinkish hue; but, as soon as food is admitted, the blood vessels
fill, the surface becomes of a bright red, and soon there exudes from the
gastric glands a thin, colorless fluid--the gastric juice. (See p. 319.)
This is secreted to the amount of twelve pounds per day. [Footnote: The
amount secreted by a healthy adult is variously estimated from five to
thirty-seven pounds. As it is reabsorbed by the blood, there is no loss.]
Its acidity is probably due to muriatic or lactic acid--the acid of sour
milk. It contains a peculiar organic principle called _pepsin_
[Footnote: Pepsin is prepared and sold as an article of commerce. The best
is said to be made from the stomachs of young, healthy pigs, which, just
before being killed, are excited with savory food that they are not
allowed to eat. One grain is sufficient to dissolve eight hundred grains
of coagulated white of egg. A temperature of 130° renders pepsin inert.]
(_peptein_, to digest), which acts as a ferment to produce changes in
the food, without being itself modified.
The flow of gastric juice is influenced by various circumstances. Cold
water checks it for a time, and ice for a longer period. Anger, fatigue,
and anxiety delay and even suspend the secretion. The gastric juice has no
effect on the fats or the sugars of the food; its influence being mainly
confined to the albuminous bodies, which it so changes that they become
soluble in water. [Footnote: The question is often asked why the stomach
itself is not digested by the gastric juice, since it belongs to the
albuminous substances. Some have assigned as the probable reason that life
protects that organ, and assert that living tissues can not be digested;
but the fallacy of this has been clearly shown by experiments that have
been made with living tissues in the course of scientific research. The
latest opinion is that the blood which circulates so freely through the
vessels of the lining of the stomach, being alkaline, protects the tissue
against the acidity of the gastric juice.]
The food, reduced by the action of the gastric juice to a grayish, soupy
mass, called _chyme_ (kime), escapes through that jealously guarded
door, the pylorus.
Fig. 48.
[Illustration: _A vertical Section of the Duodenum, highly
magnified._ 1, _a fold-like villus;_ 2, epithelium, or cuticle;_
3, _orifices of intestinal glands;_ 5, _orifice of duodenal glands;_
4, 7, _more highly magnified sections of the cells of a duodenal gland._]
III. INTESTINAL DIGESTION--The structure of the intestines is like that
of the stomach. There is the same outer, smooth, serous membrane
(peritoneum) to prevent friction, the lining of mucous membrane to secrete
the digestive fluids, and the muscular coating to push the food forward.
The intestines are divided into the _small_ and the _large_. The
first part of the former opens out of the stomach, and is called the
_du-o-de'-num_, as its length is equal to the breadth of twelve
fingers. Here the chyme is acted upon by the _bile_, and the
_pancreatic juice_.
FIG. 49.
[Illustration: _The Mucous Membrane of the Ilium, highly magnified._
1, _cellular structure of the epithelium, or outer layer;_ 2, _a
vein;_ 3, _fibrous layer;_ 4, _villi covered with epithelium;_ 5,
_a villus in section, showing its lining of epithelium, with its
blood vessels and lymphatics;_ 6, _a villus partially uncovered;_
7, _a villus stripped of its epithelium;_ 8, _lymphatics or lacteals;_
9, _orifices of the glands opening between the villi;_ 10, 11, 12,
_glands;_ 13, _capillaries surrounding the orifices of the gland._]
1. _The Bile_ is secreted by the liver. This gland weighs about four
pounds, and is the largest in the body. It is located on the right side,
below the diaphragm. The bile is of a dark, golden color, and bitter
taste. About three pounds are secreted per day. When not needed for
digestion, it is stored in the gall cyst. [Footnote: A gall bladder can be
obtained from a butcher, and the contents kept in a bottle for
examination.] Its action on the food, though not fully understood, is
necessary to life. [Footnote: The bile is produced, unlike all the other
animal secretions, from venous blood; that is, the already contaminated
blood of the portal vein. Its complete suppression produces symptoms of
poisoning analogous to those which follow the stoppage of respiration, and
the patient dies, usually in a comatose condition, at the end of ten or
twelve days.--DALTON. The alkaline bile neutralizes the acid contents of
the stomach as they flow into the duodenum, and thus prepares the way for
the pancreatic juice. It has also a slight emulsifying power (note, p.
167).]
2. _The Pancreatic Juice_ is a secretion of the pancreas, or
"sweetbread"--a gland nearly as large as the hand, lying behind the
stomach. It is alkaline, and contains a ferment called _trypsin_.
This juice has the power of changing starch to sugar. Its main work,
however, is in breaking up the globules of fat into myriads of minute
particles, that mix freely with water, and remain suspended in it like
butter in new milk. The whole mass now assumes a milky look, whence it is
termed _chyle_ (kile) and passes on to the small intestine.
[Footnote: It is curious to observe that while the gastric juice is
decidedly acid, the fluids with which the food next comes into contact are
alkaline. It is thus submitted to the operation alternately of alkaline,
acid, and again of alkaline secretions. In the herbivora there is also a
second acid juice. The reason of these alternations is not known, but it
can hardly be doubted that they serve to make the digestion of the food
more perfect. And although the solvent power of the gastric juice is
placed in abeyance when its acidity is neutralized by the alkaline fluids,
yet it appears to be the case here, as in respect to the saliva, that
effects are produced by the mixture of the various secretions which are
poured together into the digestive tube, that would not result from either
alone.--HINTON.]
3. _The Small Intestine_ is an intricately folded tube, about twenty
feet long, and from an inch to an inch and one half in diameter. As the
chyle passes through this tortuous channel, it receives along the entire
route secretions which seem to combine the action of all the previous
ones--starch, fat, and albumen being equally affected.
IV. ABSORPTION is performed in two ways, by the _veins_, and the
_lacteals_. (1.) The veins in the stomach [Footnote: The veins and
the lacteals are separated from the food by a thin, moist membrane,
through the pores of which the fluid food rapidly passes, in accordance
with a beautiful law ("Popular Physics," p. 53) called the _Osmose_
of liquids. If two liquids of different densities are separated by an
animal membrane, they will mix with considerable force. There is a similar
law regulating the interchange of gases through a porous partition, in
obedience to which the carbonic acid of the blood, and the oxygen of the
lungs, are exchanged through the thin membrane of the air cells.]
immediately begin to take up the water, salt, grape sugar, and other
substances that need no special preparation. The starch and the albuminous
bodies are also absorbed as they are properly digested, and this process
continues along the whole length of the alimentary canal. In the small
intestine, there is a multitude of tiny projections (_villi_) from
the folds of the mucous membrane, more than seven thousand to the square
inch, giving it a soft, velvety look. These little rootlets, reaching out
into the milky fluid, drink into their minute blood vessels the nutritious
part of every sort of food. (2.)The lacteals [Footnote: From _lac_,
milk, because of the milky look given to their contents by the chyle.] (p.
126), a set of vessels starting in the villi side by side with the veins,
absorb the principal part of the fat. They convey the chyle through the
lymphatics and the thoracic duct (Fig. 43) to the veins, and so within the
sweep of the circulation.
The Portal Vein [Footnote: So named because it enters the liver by a sort
of gateway.] carries to the liver the food absorbed by the veins of the
stomach and the villi of the intestines. On the way, it is greatly
modified by the action of the blood itself. In the cells of the liver, it
undergoes as mysterious a process as that performed by the lymphatic
glands, and is then cast into the circulation. [Footnote: In these cells,
the sugar is changed into a kind of starch called _glycogen_. This is
insoluble, and so is stored up in the liver, and even in the substance of
the muscles, until it is needed by the body, when it is once more
converted into soluble sugar and taken up by the circulation. The liver
also changes the waste and surplus albuminous matter into bile, and into
urea and uric acid--the forms in which nitrogenized waste is excreted by
the kidneys.] The food, potent with force, is now buried in that river of
life from which the body springs momentarily afresh.
THE COMPLEXITY of the process of digestion, as compared with the
simplicity of respiration and circulation, is very marked. The mechanical
operation of mastication; the lubrication of the food by mucus; the
provision for the security of the respiratory organs; the grasping by the
muscles of the throat; the churning movement of the stomach; the
guardianship of the pylorus; the timely introduction by safe and protected
channels of the saliva, the gastric juice, the bile, the pancreatic juice,
and the intestinal fluids, each with its special adaptation; the curious
peristaltic motion of the intestines; the twofold absorption by the veins
and the lacteals; the final transformation in the lymphatics, the portal
vein, and the liver,--all these present a complexity of detail, the
necessity of which can be explained only when we reflect upon the variety
of the substances we use for food, and the importance of its thorough
preparation before it is allowed to enter the blood.
THE LENGTH OF TIME REQUIRED for digesting a full meal is from two to four
hours. It varies with the kind of food, state of the system, perfection of
mastication, etc. In the celebrated observations made upon Alexis St.
Martin [Footnote: In 1822, Alexis St. Martin, a Canadian in the employ of
the American Fur Company, was accidentally shot in the left side. Two
years after, the wound was entirely healed, leaving, however, an opening
about two and a half inches in circumference into the stomach. Through
this the mucous membrane protruded, forming a kind of valve which
prevented the discharge of food, but could be readily depressed by the
finger, thus exposing the interior. For several years he was under the
care of Dr. Beaumont, a skillful physician, who experimented upon him by
giving various kinds of food, and watching their digestion through this
opening. By means of these observations, and others performed on Katherine
Kutt, a woman who had a similar aperture in the stomach, we have very
important information as to the digestibility of different kinds of food.]
by Dr. Beaumont, his stomach was found empty in two and a half hours after
a meal of roast turkey, potatoes, and bread. Pigs' feet and boiled rice
were disposed of in an hour. Fresh, sweet apples took one and a half
hours; boiled milk, two hours; and unboiled, a quarter of an hour longer.
In eggs, which occupied the same time, the case was reversed,--raw ones
being digested sooner than cooked. Roast beef and mutton required three
and three and a quarter hours respectively; veal, salt beef, and broiled
chicken remained for four hours; and roast pork enjoyed the bad
preeminence of needing five and a quarter hours.
VALUE OF THE DIFFERENT KINDS OF FOOD.--_Beef_ and _Mutton_
possess the greatest nutritive value of any of the meats. _Lamb_ is
less strengthening, but more delicate. Like the young of all animals, it
should be thoroughly cooked, and at a high temperature, properly to
develop its delicious flavor. _Pork_ has much carbon. It sometimes
contains a parasite called trichina, which may be transferred to the human
system, producing disease and often death. The only preventive is thorough
cooking. _Fish_ is more watery than flesh, and many find it difficult
of digestion. Like meat, it loses its mineral constituents and natural
juices when salted, and is much less nourishing. Oysters are highly
nutritious, but are more easily assimilated when raw than when cooked.
_Milk_ is a model food, as it contains albumen, starch, fat, and
mineral matter. No other single substance can sustain life for so long a
time. _Cheese_ is very nourishing--one pound being equal in value to
two of meat, but it is not adapted to a weak stomach. (See p. 322.)
_Eggs_ are most easily digested when the white is barely coagulated
and the yolk is unchanged. _Bread_ [Footnote: Very fresh bread, warm
biscuit, etc., are condensed by mastication into a pasty mass that is not
easily penetrated by the gastric juice, and hence they are not healthful.
In Germany bread is not allowed to be sold at the baker's till it is
twenty-four hours old--a wise provision for those who have not strength to
resist temptation. This rule of eating may well be adopted by every one
who cares more for his health than for a gratification of his appetite.]
should be made of unbolted flour. The bran of wheat furnishes the mineral
matter we need in our bones and teeth, gives the bulk so essential to the
proper distension of the organs, and by its roughness gently stimulates
them to action. _Corn_ is rich in fat. It contains, however, more
indigestible matter than any other grain, except oats, and is less
nutritious than wheat. [Footnote: Persons unaccustomed to the use of corn
find it liable to produce derangement of the digestive organs. This was
made fearfully apparent in the prisons of Andersonville during the late
civil war. The vegetable food of the Federal prisoners had hitherto been
chiefly wheat bread and potatoes--the corn bread so extensively used at
the South being quite new to most of them as a constant article of diet.
It soon became not only loathsome, but productive of serious diseases. On
the other hand, it was the principal article in the rations of the
Confederate soldiers, to whom habit made it a nutritious and wholesome
form of food, as was shown by their endurance.--FLINT, _Physiology of
Man_, Vol. II, page 41.] The _Potato_ is two thirds water,--the
rest being mainly starch. _Ripe Fruits_, and those vegetables usually
eaten raw, dilute the more concentrated food, and also supply the blood
with acids, which are cooling in summer, and useful, perhaps, in
assimilation.
THE STIMULANTS.--_Coffee_ is about half nitrogen, and the rest fatty,
saccharine, and mineral substances. It is, therefore, of much nutritive
value, especially when taken with milk and sugar. Its peculiar stimulating
property is due to a principle called _caffeine_. Its aroma is
developed by browning, but destroyed by burning. No other substance so
soon relieves the sense of fatigue. [Footnote: In the late civil war, the
first desire of the soldiers upon halting after a wearisome march, was to
make a cup of coffee. This was taken without milk, and often without
sugar, yet was always welcome.] Taken in moderation, it clears the
intellect, tranquilizes the nerves, and usually leaves no unpleasant
reaction. It serves also as a kind of negative food, since it retards the
process of waste.
In some cases, however, it produces a rush of blood to the head, and
should be at once discarded. At the close of a full meal it hinders
digestion, and at night produces wakefulness. In youth, when the vital
powers are strong, and the functions of nature prompt in rallying from
fatigue, it is not needed, and may be injurious in stimulating a sensitive
organization.
_Tea_ possesses an active principle called _theine_. When used
moderately, its effects are similar to those of coffee, except that it
exerts an astringent action. It contains tannin, which, if the tea is
strong, coagulates the albumen of the food--_tans_ it--and thus
delays digestion. In excess, tea causes nervous tremor, disturbed sleep,
palpitation of the heart, and indigestion. [Footnote: Tea and coffee
should be made with, boiling water, but should not be boiled afterward.
During the "steeping" process, so customary in this country, the volatile
aroma is lost and a bitter principle extracted. In both England and China
it is usual to infuse tea directly in the urn from which it is to be
drawn. The tannin in tea is shown when a drop falls on a knife blade. The
black spot is a tannate of iron--a compound of the acid in the tea and the
metal.] (See p. 322.)
_Chocolate_ contains much fat, and also nitrogenous matter resembling
albumen. Its active principle, _theobromine_, [Footnote: It is said
that Linnæus, the great botanist, was so fond of chocolate that he named
the cocoa tree "Theobroma," the food of the gods.] has some of the
properties of caffeine and theine.
THE COOKING OF FOOD breaks the little cells, and softens the fibers of
which it is composed. In broiling or roasting meat, it should be exposed
to a strong heat at once, in order to coagulate the albumen upon the
outside, and thus prevent the escape of the nutritious juices. The cooking
may then be finished at a lower temperature. The same principle applies to
boiling meat. In making soups, on the contrary, the heat should be applied
slowly, and should reach the boiling point for only a few moments at the
close. This prevents the coagulation of the albumen. Frying is an
unhealthful mode of cooking food, as thereby the fat becomes partially
disorganized.
RAPID EATING produces many evil results. 1. There is not enough saliva
mixed with the food; 2. The coarse pieces resist the action of the
digestive fluids; 3. The food is washed down with drinks that dilute the
gastric juice, and hinder its work; 4. We do not appreciate the quantity
we eat until the stomach is overloaded; 5. Failing to get the taste of our
food, we think it insipid, and hence use condiments that overstimulate the
digestive organs. In these various ways the appetite becomes depraved, the
stomach vexed, the system overworked, and the foundation of dyspepsia is
laid. [Footnote: When one is compelled to eat in a hurry, as at a railway
station, he would do well to confine himself principally to meat; and to
dilute this concentrated food with fruit, crackers, etc., taken afterward
more leisurely.] (See p. 324.)
THE QUANTITY AND QUALITY OF FOOD required vary with the age and habits of
each individual. The diet of a child [Footnote: In youth, repair exceeds
waste; hence the body grows rapidly, and the form is plump. In middle
life, repair and waste equal each other, and growth ceases. In old age,
waste exceeds repair; hence the powers are enfeebled and the skin lies in
wrinkles on the shrunken form.] should be largely vegetable, and more
abundant than that of an aged person. A sedentary occupation necessitates
less food than an outdoor life. One accustomed to manual labor, on
entering school, should practice self-denial until his system becomes
fitted to the new order of things. He should not, however, fall into the
opposite error. We read of great men who have lived on bread and water,
and the conscientious student sometimes thinks that, to be great, he, too,
must starve himself. [Footnote: As Dr. Holland well remarks, the
dispensation of sawdust has passed away. If we desire a horse to win the
race, we must give him plenty of oats.] On the contrary, many of the
greatest workers are the greatest eaters. A powerful engine needs a
corresponding furnace. Only, we should be careful not to use more fuel
than is needed to run the machine. (See p. 325.)
The season should modify our diet. In winter, we need highly carbonaceous
food, plenty of meat, fat, etc.; but in summer we should temper the heat
in our corporeal stoves with fruits and vegetables.
The climate also has its necessities. The inhabitants of the frigid north
have an almost insatiable longing for fat. [Footnote: Dr. Hayes, the
arctic explorer, says, that the daily ration of the Esquimaux was from
twelve to fifteen pounds of meat, one third being fat. On one occasion, he
saw a man eat ten pounds of walrus flesh and blubber at a single meal. The
low temperature had a remarkable effect on the members of his own party,
and some of them were in the habit of drinking the contents of the oil
kettle with evident relish. Other travelers narrate the most incredible
stories of the voracity of the inhabitants of arctic regions. Saritcheff,
a Russian admiral, tells of a man who in his presence ate, at a meal, a
mess of twenty-eight pounds of boiled rice and butter, although he had
already partaken of his breakfast. Captain Cochrane further adds, in
narrating this statement, that he has himself seen three of the savages
consume a reindeer at a sitting.] Thus, in 1812, when the Allies entered
Paris, the Cossacks drank all the oil from the lamps, and left the streets
in darkness. In tropical regions, a low, unstimulating diet of fruits
forms the chief dependence. [Footnote: A natural appetite for a particular
kind of food is an expression not only of desire, but of fitness. Thus the
craving of childhood for sugar indicates a need of the system. It is
questionable how far it is proper to force or persuade one to eat that
which he disrelishes, or his stomach loathes. Life within is linked with
life without. Each organ requires its peculiar nutriment, and there is
often a peculiar influence demanded of which we can have no notice except
by natural instinct. Yet, as we are creatures of habit and impulse, we
need common sense and good judgment to correct the too often wayward
promptings of an artificial craving.]
WHEN FOOD SHOULD BE TAKEN.--On taking food, the blood sets at once to the
alimentary canal, and the energies are fixed upon the proper performance
of this work. We should not, therefore, undertake hard study, labor, or
exercise directly after a hearty meal. We should give the stomach at least
half an hour. He who toils with brain or muscle, and thus centers the
blood in any particular organ, before eating should allow time for the
circulation to become equalized. There should be an interval of four to
five hours between our regular meals, and there should be no lunching
between times. With young children, where the vital processes are more
rapid, less time may intervene. As a general rule, nothing should be eaten
within two or three hours of retiring. (See p 336.)
HOW FOOD SHOULD BE TAKEN.--A good laugh is the best of sauces. The
mealtime should be the happiest hour of the day. Care and grief are the
bitter foes of digestion. A cheerful face and a light heart are friends to
long life, and nowhere do they serve us better than at the table. God
designed that we should enjoy eating, and that, having stopped before
satiety was reached, we should have the satisfaction always attendant on a
good work well done.
NEED OF VARIETY.--Careful investigations have shown that any one kind of
food, however nutritious in itself, fails after a time to preserve the
highest working power of the body. Our appetite palls when we confine our
diet to a regular routine. Nature demands variety, and she has furnished
the means of gratifying it. [Footnote: She opens her hand, and pours forth
to man the treasures of every land and every sea, because she would give
to him a wide and vigorous life, participant of all variety. For him the
cornfields wave their golden grain--wheat, rye, oats, maize, or rice, each
different, but alike sufficing. Freely for him the palm, the date, the
banana, the breadfruit tree, the pine, spread out a harvest on the air;
and pleasant apple, plum, or peach solicit his ready hand. Beneath his
foot lie stored the starch of the potato, the gluten of the turnip, the
sugar of the beet; while all the intermediate space is rich with juicy
herbs.
Nature bids him eat and be merry; adding to his feast the solid flesh of
bird, and beast, and fish, prepared as victims for the sacrifice: firm
muscle to make strong the arm of toil, in the industrious temperate zone;
and massive ribs of fat to kindle inward fires for the sad dwellers under
arctic skies.--_Health and its Conditions_.--HINTON.]
THE WONDERS OF DIGESTION.--We can understand much of the process of
digestion. We can look into the stomach and trace its various steps.
Indeed, the chemist can reproduce in his laboratory many of the
operations; "a step further," as Fontenelle has said, "and he would
surprise nature in the very act." Just here, when he seems so successful,
he is compelled to pause. At the threshold of life the wisest physiologist
reverently admires, wonders, and worships.
How strange is this transformation of food to flesh! We make a meal of
meat, vegetables, and drink. Ground by the teeth, mixed by the stomach,
dissolved by the digestive fluids, it is swept through the body. Each
organ, as it passes, snatches its particular food. Within the cells of the
tissues [Footnote: As the body is composed of individual organs, and each
organ of separate tissues, so each tissue is made up of minute cells. Each
cell is a little world by itself, too small to be seen by the naked eye,
but open to the microscope. It has its own form and constitution as much
as a special organ in the body. It absorbs from the blood such food as
suits its purposes. Moreover, the number of cells in an organ is as
constant as the number of organs. As the organs expand with the growth of
the body, so the cells of each tissue enlarge, but shrink again with age
and the decline of life. Life begins and ends in a cell.--See
_Appletons' Cyclopedia_, Art. "Absorption."] it is transformed into
the soft, sensitive brain, or the hard, callous bone; into briny tears, or
bland saliva, or acrid perspiration; bile for digestion, oil for the hair,
nails for the fingers, and flesh for the cheek.
Within us is an Almighty Architect, who superintends a thousand builders,
which make in a way past all human comprehension, here a fiber of a
muscle, there a filament of a nerve; here constructing a bone, there
uniting a tendon,--fashioning each with scrupulous care and unerring
nicety. [Footnote: See COOKE'S _Religion and Chemistry_, page 236.]
So, without sound of builder or stroke of hammer, goes up, day by day, the
body--the glorious temple of the soul.
DISEASES ETC.--1. _Dyspepsia_, or indigestion of food, is generally
caused by an overtaxing of the digestive organs. Too much food is used,
and the entire system is burdened by the excess. Meals are taken at
irregular hours, when the fluids are not ready. A hearty supper is eaten
when the body, wearied with the day's labor, demands rest. The appetite
craves no food when the digestion is enfeebled, but stimulants and
condiments excite it, and the unwilling organs are oppressed by that which
they can not properly manage.
Strong tea, alcoholic drinks, and tobacco derange the alimentary function.
Too great variety of dishes, rich food, tempting flavors,--all lead to an
overloading of the stomach. This patient, long-suffering member at last
wears out. Pain, discomfort, diseases of the digestive organs, and
insufficient nutrition are the penalties of violated laws. (See p. 328.)
2. _The Mumps_ are an inflammation of the parotid and submaxillary
glands (see p. 159). The disease is generally epidemic, and is believed to
be contagious; the patient should therefore be carefully secluded for the
sake of others as well as himself. The swelling may be allowed to take its
course. Relief from pain is often experienced by applying flannels wrung
out of hot water. Great care should be used not to check the inflammation,
and, on first going out after recovery, not to take cold.
ALCOHOLIC DRINKS AND NARCOTICS.
1. ALCOHOL (Continued from p. 147).
RELATION OF ALCOHOL TO THE DIGESTIVE ORGANS.--_Is Alcohol a Food?_ To
answer this question, let us make a comparison. If you receive into your
stomach a piece of bread or beef, Nature welcomes its presence. The juices
of the system at once take hold of it, dissolve it, and transform it for
the uses of the body. A million tiny fingers (lacteals and veins) reach
out to grasp it, work it over, and carry it into the circulation. The
blood bears it onward wherever it is needed to mend or to build "The house
you live in." Soon, it is no longer bread or beef; it is flesh on your
arm; its chemical energy is imparted to you, and it becomes your strength.
If, on the other hand, you take into your stomach a little alcohol, it
receives no such welcome. Nature treats it as a poison, and seeks to rid
herself of the intruder as soon as possible. [Footnote: Food is digested,
alcohol is not. Food warms the blood, directly or indirectly; alcohol
lowers the temperature. Food nourishes the body, in the sense of
assimilating itself to the tissues; alcohol does not. Food makes blood;
alcohol never does anything more innocent than mixing with it. Food feeds
the blood cells; alcohol destroys them. Food excites, in health, to normal
action only; alcohol tends to inflammation and disease. Food gives force
to the body; alcohol excites reaction and wastes force, in the first
place, and in the second, as a true narcotic, represses vital action and
corresponding nutrition.--If alcohol does not act like food, neither does
it behave like water. Water is the subtle but innocent vehicle of
circulation, which dissolves the solid food, holds in play the chemical
and vital reactions of the tissues, conveys the nutritive solutions from
cell to cell, from tube to tube, and carries off and expels the effete
matter. Water neither irritates tissue, wastes force, nor suppresses vital
action: whereas alcohol does all three. Alcohol hardens solid tissue,
thickens the blood, narcotizes the nerves, and in every conceivable
direction antagonizes the operation and function of water--LEES.] The
juices of the system will flow from every pore to dilute and weaken it,
and to prevent its shriveling up the delicate membranes with which it
comes in contact. The veins will take it up and bear it rapidly through
the system. Every organ of elimination, all the scavengers of the body--
the lungs, the kidneys, the perspiration glands, at once set to work to
throw off the enemy. So surely is this the case, that the breath of a
person who has drunk only a single glass of the lightest beer will betray
the fact.
The alcohol thus eliminated is entirely unchanged. Nature apparently makes
no effort to appropriate it. [Footnote: It was formerly a question
considerably discussed, whether alcohol exists in the brain, or in the
fluid found in the ventricles, in intoxicated persons. This was settled by
Percy, who found alcohol in the brain and liver of dogs poisoned with
alcohol, and of men who had died after excessive drinking. In these
experiments, the presence of alcohol was determined by distillation, and
the distilled substance burned with a blue flame, and dissolved camphor.--
FLINT'S _Physiology of Man_.] It courses everywhere through the
circulation, and into the great organs, with all its properties
unmodified.
Alcohol, then, is not, like bread or beef, taken hold of, broken up by the
mysterious process of digestion, and used by the body. [Footnote: Because
of the difficulties of such an experiment, we have not yet been able to
account satisfactorily by the excretions for all the alcohol taken into
the stomach. This remains as yet one of the unsolved problems of
physiological chemistry. To collect the whole of the insensible
perspiration, for example, is well-nigh impossible. It was supposed at one
time that a part of the alcohol is oxidized--_i. e._, burned, in the
system. But such a process would impart heat, and it is now proved that
alcohol cools, instead of warms, the blood. Moreover, the closest analysis
fails to detect in the circulation any trace of the products of alcoholic
combustion, such as aldehyde and acetic acid. "The fact," says Flint,
"that alcohol is always eliminated, even when drunk in minute quantity,
and that its elimination continues for a considerable time, gradually
diminishing, renders it probable that all that is taken into the body is
removed."] "It can not therefore be regarded as an aliment," or food.--
FLINT. "Beer, wine, and spirits," says Liebig, "contain no element capable
of entering into the composition of the blood or the muscular fiber."
[Footnote: The small amount of nutritive substance, chiefly sugar derived
from the grain or fruit used in the manufacture of beer or wine, can not,
of course, be compared with that contained in bread or beef at the same
cost. Liebig says, in his Letters on Chemistry, "We can prove, with
mathematical certainty, that as much flour as can lie on the point of a
table knife is more nutritious than eight quarts of the best Bavarian
beer."] "That alcohol is incapable of forming any part of the body,"
remarks Cameron, "is admitted by all physiologists. It can not be
converted into brain, nerve, muscle, or blood."
EFFECT UPON THE DIGESTION. [Footnote: The medical value of alcohol in its
relations to digestion is not discussed in this book. The experiments of
Dr. Henry Munroe, of Hull, published in the London _Medical Journal_,
are here summarized as showing that the tendency to retard digestion is
common to all forms of alcoholic drinks.
_______________________________________________________________________
Finely Minced | | | |
Beef | 2d Hour | 4th Hour | 6th Hour |
_______________________________________________________________________
I. | | Digesting | |
Gastric Juice | Beef | and | Beef much |
and _water_. | opaque. | separating. | loosened. |
_______________________________________________________________________
| | Slightly | Slight |
II. | No alteration | opaque, but | coating on |
Gastric Juice | perceptible. | beef | beef. |
with _alcohol_. | | unchanged. | |
_______________________________________________________________________
III. | | Cloudy, | beef |
Gastric Juice | No change. | with fur | partly |
and _pale ale_. | | on beef. | loosened. |
_______________________________________________________________________
______________________________________________________
Finely Minced | | |
Beef | 8th Hour | 10th Hour |
______________________________________________________
I. | | |
Gastric Juice | Beef | Broken up |
and _water_. | opaque. | into shreds. |
______________________________________________________
| | Solid on |
II. | No visible | cooling |
Gastric Juice | change. | _Pepsin_ |
with _alcohol_. | | precipitated. |
______________________________________________________
III. | | No digestion |
Gastric Juice | No further | _Pepsin_ |
and _pale ale_. | change. | precipitated. |
______________________________________________________]
--Experiments tend to prove that alcohol coagulates and precipitates the
pepsin from the gastric juice, and so puts a stop to its great work in the
process of digestion.
The greed of alcohol for water causes it to imbibe moisture from the
tissues and juices, and to inflame the delicate mucous membrane. It shows
the power of Nature to adapt herself to circumstances, that the soft,
velvety lining of the throat and stomach should come at length to endure
the presence of a fiery liquid which, undiluted, would soon shrivel and
destroy it. In self-defense, the juices pour in to weaken the alcohol, and
it is soon hurried into the circulation. Before this can be done, "it must
absorb about three times its bulk of water"; hence, very strong liquor may
be retained in the stomach long enough to interfere seriously with the
digestion, and to injure the lining coat. Habitual use of alcohol
permanently dilates the blood vessels; thickens and hardens the membranes;
in some cases, ulcerates the surface; and, finally, "so weakens the
assimilation that the proper supply of food can not be appropriated."
--FLINT. [Footnote: The case of St. Martin (p. 168) gave an excellent
opportunity to watch the action of alcohol upon the stomach. Dr. Beaumont
summarized his experiments thus: "The free, ordinary use of any
intoxicating liquor, when continued for some days, invariably produced
inflammation, ulcerous patches, and, finally, a discharge of morbid matter
tinged with blood." Yet St. Martin never complained of pain in his
stomach, the narcotic influence of the alcohol preventing the signal of
danger that Nature ordinarily gives.]
EFFECT UPON THE LIVER.--Alcohol is carried by the portal vein directly to
the liver. This organ, after the brain, holds the largest share. The
influence of the poison is here easily traced. "The color of the bile is
soon changed from yellow to green, and even to black;" the connective
tissue between the lobules becomes inflamed; and, in the case of a
confirmed drunkard, hardened and shrunk, the surface often assuming a
nodulated appearance known as the "hobnailed liver." Morbid matter is
sometimes deposited, causing what is called "Fatty degeneration," so that
the liver is increased to twice or thrice its natural size.
EFFECT UPON THE KIDNEYS.--The kidneys, like the liver, are liable in time
to undergo, through the influence of alcohol, a "Fatty degeneration," in
which the cells become filled with particles of fat; [Footnote: Disabled
by the fatty deposits, the kidneys are unable to separate the waste matter
coming to them for elimination from the system. The poisonous material is
poured back into the circulation, and often delirium ensues.--HUBBARD.
Richardson states that his experience "is to the effect that seven out of
every eight instances of kidney disease are attributable to alcohol."] the
vessels lose their contractility; and, worst of all, the membranes may be
so modified as to allow the albuminous part of the blood to filter through
them, and so to rob the body of one of its most valuable constituents.
[Footnote: This deterioration of structure frequently gives rise to what
is known as "Bright's Disease."--RICHARDSON.]
DOES ALCOHOL IMPART HEAT?--During the first flush after drinking wine, for
example, a sense of warmth is felt. This is due to the tides of warm blood
that are being sent to the surface of the body, owing to the vascular
enlargement and to the rapid pumping of the heart. There is, however, no
fresh heat developed. On the contrary, the bringing the blood to the
surface causes it to cool faster, reaction sets in, a chilliness is
experienced as one becomes sober, and a delicate thermometer placed under
the tongue of the inebriate may show a fall of even two degrees below the
standard temperature of the body. Several hours are required to restore
the usual heat.
As early as 1850, Dr. N. S. Davis, of Chicago, ex-President of the
American Medical Association, instituted an extensive series of
experiments to determine the effect of the different articles of food and
drinks on the temperature of the system. He conclusively proved that,
during the digestion of all kinds of food, the temperature of the body is
increased, but when alcohol is taken, either in the form of fermented or
distilled beverages, the temperature begins to fall within a half hour,
and continues to decrease for two or three hours, and that the reduction
of temperature, in extent as well as in duration, is in exact proportion
to the amount of alcohol taken.
It naturally follows that, contrary to the accepted opinion, liquor does
not fortify against cold. The experience of travelers at the North
coincides with that of Dr. Hayes, the Arctic explorer, who says: "While
fat is absolutely essential to the inhabitants and travelers in arctic
countries, alcohol is, in almost any shape, not only completely useless,
but positively injurious. I have known strong, able-bodied men to become
utterly incapable of resisting cold in consequence of the long-continued
use of alcoholic drink."
DOES ALCOHOL IMPART STRENGTH?--Experience shows that alcohol weakens the
power of undergoing severe bodily exertion. [Footnote: Dr. McRae, in
speaking of Arctic exploration, at the meeting of the American Association
for the Advancement of Science, held at Montreal in 1856, said: "The
moment that a man had swallowed a drink of spirits, it was certain that
his day's work was nearly at an end. It was absolutely necessary that the
rule of total abstinence be rigidly enforced, if we would accomplish our
day's task. The use of liquor as a beverage when we had work on hand, in
that terrific cold, was out of the question."] Men who are in training for
running, rowing, and other contests where great strength is required, deny
themselves all liquors, even when they are ordinarily accustomed to their
use.
Dr. Richardson made some interesting experiments to show the influence of
alcohol upon muscular contraction. He carefully weighted the hind leg of a
frog, and, by means of electricity, stimulating the muscle to its utmost
power of contraction, he found out how much the frog could lift. Then
administering alcohol, he discovered that the response of the muscle to
the electrical current became feebler and feebler, as the narcotic began
to take effect, until, at last, the animal could raise less than half the
amount it lifted by the natural contraction when uninfluenced by alcohol.
EFFECT UPON THE WASTE OF THE BODY.--The tendency of alcohol is to cause a
formation of an unstable substance resembling fat, [Footnote: The
molecular deposits equalizing the waste of the system do not go on
regularly under the influence of alcohol; the tissues are not kept up to
their standard; and, in time, their composition is changed by a deposit of
an amorphous matter resembling fat. This is an unstable substance, and the
functions of animal life all retrograde.--HUBBARD, _The Opium Habit and
Alcoholism_.] and so the use of liquor for even a short time will
increase the weight. But a more marked influence is to check the ordinary
waste of the system, so that "the amount of carbonic acid exhaled from the
lungs may be reduced as much as thirty to fifty per cent."--HINTON. The
life process is one of incessant change. Its rapidity is essential to
vigor and strength. When the functions are in full play, each organ is
being constantly torn down, and as constantly rebuilt with the materials
furnished from our food. Anything that checks this oxidation of the
tissues, or hinders the deposition of new matter, disturbs the vital
functions. Both these results are the inevitable effects of alcohol; for,
since the blood contains less oxygen and more carbonic acid, and the power
of assimilating the food is decreased, it follows that every process of
waste and repair must be correspondingly weakened. The person using liquor
consequently needs less bread and beef, and so alcohol seems to him a
food--a radical error, as we have shown.
ALCOHOL CREATES A PROGRESSIVE APPETITE FOR ITSELF.--When liquor is taken,
even in the most moderate quantity, it soon becomes necessary, and then
arises a craving demand for an increased amount to produce the original
effect. No food creates this constantly augmenting want. A cup of milk
drank at dinner does not lead one to go on, day by day, drinking more and
more milk, until to get milk becomes the one great longing of the whole
being. Yet this is the almost universal effect of alcohol. Hunger is
satisfied by any nutritious food: the dram-drinker's thirst demands
alcohol. The common experience of mankind teaches us the imminent peril
that attends the formation of this progressive poison habit. A single
glass taken as a tonic may lead to the drunkard's grave.
Worse than this, the alcoholic craving may be transmitted from father to
son, and young persons often find themselves cursed with a terrible
disease known as alcoholism--a keen, morbid appetite for liquor that
demands gratification at any cost--stamped upon their very being through
the reckless indulgence of this habit on the part of some one of their
ancestors. [Footnote: The American Medical Association, at their meeting
in St. Paul, Minnesota (1883), restated in a series of resolutions their
conviction, that "alcohol should be classed with other powerful drugs;
that when prescribed medically, it should be done with conscientious
caution and a sense of great responsibility; that used as a beverage it is
productive of a large amount of physical and mental disease; that it
_entails diseased and enfeebled constitutions upon offspring_, and
that it is the cause of a large percentage of the crime and pauperism of
our large cities and country."]
THE LAW OF HEREDITY is, in this connection, well worth consideration. "The
world is beginning to perceive," says Francis Galton, "that the life of
each individual is, in some real sense, a continuation of the lives of his
ancestors." "Each of us is the footing up of a double column of figures
that goes back to the first pair." "We are omnibuses," remarks Holmes, "in
which all our ancestors ride." We inherit from our parents our features,
our physical vigor, our mental faculties, and even much of our moral
character. Often, when one generation is skipped, the qualities will
reappear in the following one. The virtues, as well as the vices, of our
forefathers, have added to, or subtracted from, the strength of our brain
and muscle. The evil tendencies of our natures, which it is the struggle
of our lives to resist, constitute a part of our heirlooms from the past.
Our descendants, in turn, will have reason to bless us only if we hand
down to them a pure healthy physical, mental, and moral being.
"There is a marked tendency in nature to transmit all diseased conditions.
Thus, the children of consumptive parents are apt to be consumptives. But
of all agents, alcohol is the most potent in establishing a heredity that
exhibits itself in the destruction of mind and body. [Footnote: Nearly all
the diseases springing from indulgence in distilled and fermented liquors
are liable to become hereditary, and to descend to at least three or four
generations, unless starved out by uncompromising abstinence. But the
distressing aspect of the heredity of alcohol is the transmitted drink-
crave. This is no dream of an enthusiast, but the result of a natural law.
Men and women upon whom this dread inheritance has been forced are
everywhere around us, bravely struggling to lead a sober life.--DR.
NORMAN KERR.] Its malign influence was observed by the ancients long
before the production of whiskey or brandy, or other distilled liquors,
and when fermented liquors or wines only were known. Aristotle says,
'Drunken women have children like unto themselves,' and Plutarch remarks,
'One drunkard is the father of another.' The drunkard by inheritance is a
more helpless slave than his progenitor, and his children are more
helpless still, unless on the mother's side there is an untainted blood.
For there is not only a propensity transmitted, but an actual disease of
the nervous system."--DR. WILLARD PARKER. [Footnote: The subject of
alcohol is continued in the chapter on the Nervous System.]
PRACTICAL QUESTIONS.
1. How do clothing and shelter economize food?
2. Is it well to take a long walk before breakfast?
3. Why is warm food easier to digest than cold?
4. Why is salt beef less nutritious than fresh? [Footnote: The French
Academicians found that flesh soaked in water so as to deprive it of its
mineral matter and juices, lost its nutritive value, and that animals fed
on it soon died. Indeed, for all purposes of nutrition, Liebig said it was
no better than stones, and the utmost torments of hunger were hardly
sufficient to induce them to continue the diet. There was plenty of
nutritive food, but there was no medium for its solution and absorption,
and hence it was useless.] 5. What should be the food of a man recovering
from a fever?
6. Is a cup of black coffee a healthful close to a hearty dinner?
7. Should iced water be used at a meal?
8. Why is strong tea or coffee injurious?
9. Should food or drink be taken hot?
10. Are fruitcakes, rich pastry, and puddings wholesome?
11. Why are warm biscuit and bread hard of digestion?
12. Should any stimulants be used in youth?
13. Why should bread be made spongy?
14. Which should remain longer in the mouth, bread or meat?
15. Why should cold water be used in making soup, and hot water in boiling
meat?
16. Name the injurious effects of overeating.
17. Why do not buckwheat cakes, with syrup and butter, taste as well in
July as in January?
18. Why is a late supper injurious?
19. What makes a man "bilious"?
20. What is the best remedy? _Ans_. Diet to give the organs rest, and
active exercise to arouse the secretions and the circulation.
21. What is the practical use of hunger?
22. How can jugglers drink when standing on their heads?
23. Why do we relish butter on bread?
24. What would you do if you had taken arsenic by mistake? (See Appendix.)
25. Why should ham and sausage be thoroughly cooked?
26. Why do we wish butter on fish, eggs with tapioca, oil on salad, and
milk with rice?
27. Explain the relation of food to exercise.
28. How do you explain the difference in the manner of eating between
carnivorous and herbivorous animals?
29. Why is a child's face plump and an old man's wrinkled?
30. Show how life depends on repair and waste.
31. What is the difference between the decay of the teeth and the constant
decay of the body?
32. Should biscuit and cake containing yellow spots of soda be eaten?
33. Tell how the body is composed of organs, how organs are made up of
tissues, and how tissues consist of cells.
34. Why do we not need to drink three pints of water per day?
35. Why, during a pestilence, are those who use liquors as a beverage the
first, and often the only victims?
36. What two secretions seem to have the same general use?
37. How may the digestive organs be strengthened?
38. Is the old rule, "after dinner sit awhile," a good one?
39. What would you do if you had taken laudanum by mistake? Paris Green?
Sugar of lead? Oxalic acid? Phosphorus from matches? Ammonia? Corrosive
sublimate? (See p. 265.)
40. What is the simplest way to produce vomiting, so essential in case of
accidental poisoning?
41. In what way does alcohol interfere with the digestion?
42. Is alcohol assimilated?
43. What is the effect of alcohol on the albuminous substances?
44. Is there any nourishment in beer?
45. Show how the excessive use of alcohol may first increase, and,
afterward, decrease, the size of the liver.
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