Hygienic Physiology
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Joel Dorman Steele >> Hygienic Physiology
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In addition to all this, the air is filled with dust brought in and kept
astir by many busy feet; with ashes floating from the stove or furnace;
and especially with chalk dust. The modern method of teaching requires a
large amount of blackboard work, and the air of the schoolroom is thus
loaded with chalk particles. These collect in the nasal passages, and the
upper part of the larynx, and irritate the membrane, perhaps laying the
foundation of catarrh.
The usual schoolroom atmosphere bears in the pupils the natural fruit of
frequent headaches, inattention, weariness, and stupor; but in the teacher
its frightful influence is most apparent. His labor is severe, his worry
of mind is constant, and, when he finishes his day's work, he is generally
too tired to take proper physical exercise. He consequently labors on with
impaired health, or is forced to abandon his profession.
Instead of six hundred feet of space being allowed for each pupil, as
perfect ventilation demands--the lowest estimate being two hundred and
fifty feet--often not over one hundred feet are afforded. Instead of two
thousand cubic feet of fresh air being supplied every hour for each
person, and as much foul air removed, which, all physiologists assert, is
needed for perfect health, perhaps no means of ventilation at all are
provided, and none is secured except what an occasionally opened door, or
the benevolent cracks and chinks in the building furnish the suffering
lungs. [Footnote: Imagine fifty pupils put into a class room thirty feet
long, twenty-five feet wide, and ten feet high. This would generally be
considered a very liberal provision. Such a room contains seven thousand
five hundred cubic feet of air. But it furnishes only one hundred and
fifty feet of space for each pupil. Allowing ten cubic feet of air per
pupil each minute, in fifteen minutes after assembling, the entire
atmosphere of the room is tainted, and unfit to be rebreathed. The demand
of health is that at least one thousand five hundred cubic feet of pure
air should be admitted into this room every minute, and as much be
removed.]
HOW SHALL WE VENTILATE?--The usual method of ventilation depends upon the
fact that hot air is lighter than cold air, and so the cold air tends, by
the force of gravity, to fall and compel the warm air to rise. Thus, if we
open the door of a heated room, and hold a lighted candle first at the
top, and then at the bottom, we can see, by the deflection of the flame,
that there is a current of air setting outward at the top, and another
setting inward at the bottom of the opening. A handkerchief held loosely,
or the smoke of a smoldering match, in front of a fireplace will show a
current of air passing up the chimney; this is caused by the difference of
temperature between the air in the room and the outside atmosphere.
_Upon this difference of temperature, all ordinary ventilation is
based_. [Footnote: Public buildings are sometimes ventilated by
mechanical means, _i. e._, immense fans which are turned by
machinery, and thus set the air in motion. Such methods are, however,
expensive, and rarely adopted, except where power is also used for other
purposes.] A proper treatment of this subject and its practical
applications, would require a book by itself. There is room here for only
a few general statements and suggestions.
1. Two openings are always necessary to produce a thorough change of air.
(See "Popular Chemistry," p. 70.) Put a lighted candle in a bottle. The
flame will soon be extinguished. The oxygen of the little air in the
bottle is burned out, and carbonic acid has taken its place. Now place
over the mouth of the bottle a lamp chimney, and insert in the chimney a
strip of cardboard, thus dividing the passage. On relighting the candle,
it will burn freely. The smoke of a bit of smoldering paper will show that
two opposite currents of air are established, one setting into the bottle,
the other outward.
2. In the winter, when our schoolrooms, churches, public halls, etc., are
heated artificially, ventilation is comparatively easy if properly
arranged. [Footnote: For the escape of bad air, Dr. Bell suggests that an
efficient foul-air shaft may be fitted to the commonest of stoves by
simply inclosing the stovepipe in a jacket--that is, in a pipe two or
three inches greater in diameter. This should be braced round the
stovepipe and left open at the end next the stove. At its entrance into
the chimney, a perforated collar should separate it from the stovepipe.]
The required difference of temperature is kept up with little difficulty.
The fresh air admitted to the room should then be heated [Footnote:
Ventilation is change of air, and, unless scientifically arranged, and
especially unless the incoming volume of air be warmed in cold weather,
such change of atmosphere means cold currents, with their attendant train
of catarrhs, bronchitis, neuralgia, rheumatism, and all the evils that
spring from these diseases. The raw, damp, frosty air of our ever-changing
winter temperature ought not to have uncontrolled and constant ingress to
our dwellings. Air out of doors is suited to out of door habits. It is
healthy and bracing when the body is coated and wrapped, and prepared to
meet it, and when exercise can be taken to keep up the circulation; but to
live under cover is to live artificially, and such essential conditions
must be observed as suit an abnormal state. All the evils attaching to
ventilation, as it is generally effected, spring from the neglect of this
consistency.--_Westminster Review_.] either by a furnace, or by
passing over a stove, or through a coil of steam pipes. This cold air
should always be taken directly from out of doors, and not from a cellar,
or from under a piazza, where contamination is possible.
3. In order to remove the impure air, there should be ventilators provided
at or near the floor, opening into air shafts, or pipes leading upward
through the roof, with proper orifices at the top. These ventilating pipes
should be heated artificially so as to produce a draught. They may form
one of the flues of a chimney in which there is a constant fire; or be
carried upward in a large flue through the center of which runs the smoke
pipe of the furnace or stove; [Footnote: This plan has been adopted in the
newer school buildings of Elmira, N. Y. The older buildings were provided
with ventilating pipes, not heated artificially, and hence of no service.
These pipes are rendered effective, however, by conducting them into a
small room in the garret, heated by a coal stove. From this room, a large
exit pipe leads to the roof, where it terminates in an Emerson's
ventilator. So strong a draught is thus established that throughout the
building air is taken from the floors, and consequently the cooler portion
of the rooms, at a velocity of three to five feet per second or one
hundred and eighty to three hundred cubic feet per minute for each square
foot of flue opening. In perpendicular flues, heated throughout with a
smoke flue from the furnace, ten feet per second is attained.] or the
ventilating pipe be itself conveyed through the center of the larger
chimney flue. If the register for hot air be on the floor at one side of
the room, two or more ventilators may be placed near the floor on the
opposite side. The warm air will thus make the complete circuit of the
room, and thoroughly warm it before passing out.
If the ventilating shaft be not heated artificially; the ventilator must
be placed at the top of the room in order that the hot air may escape
through it, thus producing an upward draught. But the objection to this
method is that it allows the warmer air to escape, while economy requires
that the cooler air at the bottom of the room should be removed and the
warm air be made to descend, thus securing uniformity of temperature.
4. In the summer, ventilation may be commonly provided for by opening
windows _at the top and the bottom_, on the sheltered side of the
building, so as to avoid draughts of air injurious to the occupants. On a
dull, still, hot day, when there is little difference of temperature
between the inner and the outer air, ventilation can be secured only by
having a fire provided in the ventilating shaft; this, by exhausting the
air from the room, will cause a fresh current to pour in through the open
windows. At recess, all the children should, if the weather permit, be
sent out of doors, to allow their clothing to be exposed to the purifying
influence of the open air; meantime, the windows should be thrown wide
open, that the room may be thoroughly ventilated during their absence. In
bad weather, rapid marching or calisthenic exercises will furnish
exercise, and also permit the airing of the room.
5. The school and the church are the centers for spreading contagious
diseases. The former offers especially dangerous facilities for scattering
disease germs. Great pains, therefore, should be taken to exclude pupils
attacked by or recovering from diphtheria, scarlet fever, whooping cough,
etc., and even those who live in houses where such sickness exists.
6. In our houses [Footnote: The air of our homes is often contaminated by
decaying vegetables and other filth in the cellar; by bad air drawn up
from the soil into the cellar, by the powerful draughts that our fires
create; by defective gas and waste pipes that let the foul air from
cesspool or sewer spread through the house; and by piles of refuse, or
puddles of slops emptied at the back door. Too often, also, the water in
our wells, or in the streams that supply our towns and cities, receives
the drainage from outhouses and barnyards, and so introduces into our
systems, in the liquid--and thus easily assimilated--form, the most
dangerous poisons. The question of sanitary precautions is one that
presses upon every observant mind, and demands constant and thoughtful
attention. (See p. 305.)] open fireplaces are efficient ventilators, and
they should never be closed for any cause. Fresh air admitted by a hot-air
register and impure air passed out by a chimney, form a simple and
thorough system. Our sleeping apartments demand especial care. As soon as
the occupants leave the room, the bedclothes should be removed, and laid
on the backs of chairs to air; the bed be shaken up; and the windows
thrown open. In the summer, the windows may be closed before the sun is
high; the house is then left filled with the cool morning air. In damp and
cold weather, a fire should be lighted in sleeping apartments,
particularly if used by children [Footnote: In winter, children should
always be given a moderately warm, well-ventilated bedroom, with light,
fleecy bed coverings. Says a recent English writer: "The loving care which
prescribes for children a cold bedroom and a hot, sweltering bed is of the
nature that kills. Buried in blankets, their delicate skins become
overheated and relaxed, while they are irritated by perspiration; at the
same time, the most delicate tissues of all, in the lungs, are dealing
with air abnormally frigid. The poor little victims of combined ignorance
and kindness thus toss and dream, feverish and troubled, under a mass of
bedclothes, while the well-meaning mother, soothed by a bedroom fire,
slumbers peacefully through this working out of the sad process of the
'survival of the fittest.'"] or delicate persons, to dry the bedclothing,
and also to prevent a chill on the part of the occupants. It is not
necessary to go shivering to bed in order to harden one's constitution.
WONDERS OF RESPIRATION.--The perfection of the organs of respiration
challenges our admiration. So delicate are they that the least pressure
would cause exquisite pain, yet tons of air surge to and fro through their
intricate passages, and bathe their innermost cells. We yearly perform at
least seven million acts of breathing, inhaling one hundred thousand cubic
feet of air, and purifying over three thousand five hundred tons of blood.
This gigantic process goes on constantly, never wearies or worries us, and
we wonder at it only when science reveals to us its magnitude. In
addition, by a wise economy, the process of respiration is made to
subserve a second use no less important, and the air we exhale, passing
through the organs of voice, is transformed into prayers of faith, songs
of hope, and words of social cheer.
FIG. 33.
[Illustration: A, _the natural position of the internal organs._ B
_when deformed by tight lacing Marshall says that the liver and the
stomach have, in this way, been forced downward almost as low as the
pelvis._]
DISEASES, ETC.--1. _Constriction of the Lungs_ is produced by tight
clothing. The ribs are thus forced inward, the size of the chest is
diminished, and the amount of inhaled air decreased. Stiff clothing, and
especially a garment that will not admit of a full breath without
inconvenience, will prevent that free movement of the ribs so essential to
health. Any infraction of the laws of respiration, even though it be
fashionable, will result in diminished vitality and vigor, and will be
fearfully punished by sickness and weakness through the whole life.
2. _Bronchitis_ (bron-ki'-tis) is an inflammation (see Inflammation)
of the mucous membrane of the bronchial tubes. It is accompanied by an
increased secretion of mucus, and consequent coughing.
3. _Pleurisy_ is an inflammation of the pleura. It is sometimes
caused by an injury to the ribs, and results in a secretion of water
within the membrane.
4. _Pneumonia_ (_pneuma_, breath) is an inflammation of the
lungs, affecting chiefly the air cells.
5. _Consumption_ is a disease which destroys the substance of the
lungs. Like other lung difficulties, it is caused largely by a want of
pure air, a liberal supply of which is the best treatment that can be
prescribed for it. [Footnote: If I were seriously ill of consumption, I
would live outdoors day and night, except in rainy weather or midwinter;
then I would sleep in an unplastered log house. Physic has no nutriment,
gaspings for air can not cure you, monkey capers in a gymnasium can not
cure you, stimulants can not cure you. What consumptives want is pure air,
not physic, plenty of meat and plenty of bread.--DR. MARSHALL HALL.]
6. _Asphyxia_ (as-fix'-i-a).--When a person is drowned, strangled, or
choked in any way, what is called asphyxia occurs. The face turns black;
the veins become turgid; insensibility and often convulsions ensue. If
relief is not secured within a few minutes, death will be inevitable.
[Footnote: The lack of oxygen, and the presence of carbonic-acid gas, are
the combined causes. Oxygen starvation and carbonic-acid poisoning, each
fatal in itself, work together to destroy life.] (See p. 264.)
7. _Diphtheria_ (_diphthera_, a membrane) is characterized by
fever, debility, and a peculiar sore throat, in which exuding fibrinous
matter forms a grayish white membrane, which afterward decomposes with a
fetid odor. Its sudden and insidious approach, contagious character, and
frequent fatality, render it an exceedingly dreaded disease. A
diphtheritic patient should be quarantined, and everything connected with
the sick room thoroughly disinfected.
8. _Croup_, which often attacks young children, is an inflammation of
the mucous membrane of the larynx and trachea. It is commonly preceded by
a cold. The child sneezes, coughs, and is hoarse, but the attack
frequently comes on suddenly, and usually in the night. It is accompanied
by a peculiar "brassy," ringing cough, which, once heard, can never be
mistaken. It may prove fatal within a few hours. (See p. 260.)
9. _Stammering_ depends, not on defects of the muscles, but on a want
of due control of the mind. When a stammerer is not too conscious of his
lack, and tries to form his words slowly, he speaks plainly, and may sing
well, for then his words must follow one another in rhythmic time. Many
persons who stammer in common conversation can talk with fluency when
making a speech. The stammerer should seek to discover the cause of his
difficulty, and to overcome it by vocal and respiratory exercise,
especially by speaking only after a full inspiration, and during a long,
slow expiration.
PRACTICAL QUESTIONS.
1. What is the philosophy of "the change of voice" in a boy?
2. Why can we see our breath on a frosty morning?
3. When a law of health and a law of fashion conflict, which should we
obey?
4. If we use a "bunk" bed, should we pack away the clothes when we first
rise in the morning?
5. Why should a clothespress be well ventilated?
6. Should the weight of our clothing hang from the waist, or the shoulder?
7. Describe the effects of living in an overheated room.
8. What habits impair the power of the lungs?
9. For full, easy breathing in singing, should we use the diaphragm and
lower ribs, or the upper ribs alone?
10. Why is it better to breathe through the nose than the mouth?
11. Why should not a speaker talk while returning home on a cold night
after a lecture?
12. What part of the body needs the loosest clothing?
13. What part needs the warmest?
14. Why is a "spare bed" generally unhealthful?
15. Is there any good in sighing?
16. Should a hat be thoroughly ventilated? How?
17. Why do the lungs of people who live in cities become of a gray color?
18. How would you convince a person that a bedroom should be aired?
[Footnote: "If the condensed breath collected on the cool windowpanes of a
room where a number of persons have been assembled, be burned, a smell as
of singed hair will show the presence of organic matter; and if the
condensed breath be allowed to remain on the windows for a few days, it
will be found, on examination by the microscope, that it is alive with
animalculę."]
19. What persons are most liable to catarrhs, consumption, etc.?
20. If a person is plunged under water, will it enter his lungs?
21. Are bed curtains healthful?
22. Why do some people take "short breaths" after a meal?
23 What is the special value of public parks?
24. Can a person become used to bad air, so that it will not injure him?
25. Why do we gape when we are sleepy?
26. Is a fashionable waist a model of art in sculpture or painting?
27. Should a fireplace be closed? [Footnote: Thousands of lives would be
saved if all fireplaces were kept open. If you are so fortunate as to have
a fireplace in your room, paint it when not in use, put a bouquet of fresh
flowers in it every morning, if you please, or do anything to make it
attractive, but never _close it_; better use the fireboards for
kindling wood. It would be scarcely more absurd to take a piece of
elegantly-tinted court-plaster and stop up the nose, trusting to the
accidental opening and shutting of the mouth for fresh air, because you
thought it spoiled the looks of your face to have two such great, ugly
holes in it, than to stop your fireplace with elegantly-tinted paper, or a
Japanese fan, because it looks better.--Leeds.]
28. Why does embarrassment or fright cause a stammerer to stutter still
more painfully?
29. In the organs of voice, what parts have somewhat the same effect as
the case of a violin and the sounding-board of a piano?
30. Why should we be careful not to "take the breath of a sick person"?
31. What special care should be taken with regard to keeping a cellar
clean?
32. How is the air strained as it passes into the lungs?
33. Can one really "draw the air into his lungs"?
34. How often do we breathe?
35. Describe some approved method of ventilation.
36. What is at once the floor of the chest and the roof of the abdomen?
37. What would you do in a case of apparent death by drowning, or by coal
gas? (See p. 264.)
38. What would you do in a case of croup, while the doctor was coming?
(See p. 260.)
39. How would you treat a severe burn? (See p. 257.)
40. Describe the various ways in which the water in a well is liable to
become unwholesome.
FIG. 34.
[Illustration]
V.
THE CIRCULATION.
"No rest this throbbing slave may ask,
Forever quivering o'er his task,
While far and wide a crimson jet
Leaps forth to fill the woven net,
Which in unnumber'd crossing tides
The flood of burning life divides,
Then, kindling each decaying part,
Creeps back to find the throbbing heart."
HOLMES.
ANALYSIS OF THE CIRCULATION
_
_ | 1. Its Composition.
| 1. THE BLOOD | 2. Its Uses.
| | 3. Transfusion.
| |_4. Coagulation
| _
| | 1. _Description._
| | 2. _Movements._
| | 3. _Auricles and Ventricles._
| _ | _
| | 1. The | | a. Need of.
| | Heart.| | b. Tricuspid and
| | | | Bicuspid.
| | | 4. _The | c. The Strengthen-
| | | Valves._ | ing of the
| | | | Valves.
| | | | d. Semilunar
| | |_ |_ Valves.
| | _
| 2. ORGANS OF THE | 2. The | 1. _Description._
| CIRCULATION | Arteries | 2. _The Arterial System._
| | |_3. _The Pulse._
| | _
| | 3. The | 1. _General Description._
| | Veins |_2. _Valves._
| | _
| | 4. The | 1. _Description._
| | Capilla-| 2. _Use._
| |_ ries |_3. _Under the Microscope._
| _
| | 1. The Lesser.
| 3. THE CIRCULATION.| 2. The Greater.
| |_3. The Velocity of the Blood.
| _
| 4. THE HEAT OF THE | 1. Distribution.
| BODY. |_2. Regulation.
|
| 5. LIFE BY DEATH.
|
| 6. CHANGE OF OUR BODIES.
|
| 7. THE THREE VITAL ORGANS.
|
| 8. WONDERS OF THE HEART.
| _
| | 1. Description
| 9. THE LYMPHATIC | 2. The Glands.
| CIRCULATION. | 3. The Lymph.
| |_4. The Office of the Lymphatics.
| _
| | 1. Congestion.
| | 2. Inflammation.
| | 3. Bleeding.
| 10. DISEASES. | 4. Scrofula.
| | 5. A Cold.
| |_6. Catarrh.
| _
| | 1. Effect of Alcohol upon the Circulation.
| 11. ALCOHOLIC | 2. Effect of Alcohol upon the Heart.
| DRINKS AND | 3. Effect of Alcohol upon the Membrane.
|_ NARCOTICS. | 4. Effect of Alcohol upon the Blood.
|_5. Effect of Alcohol upon the Lungs.
THE CIRCULATION.
THE ORGANS OF THE CIRCULATION are the _heart_, the _arteries_,
the _veins_, and the _capillaries_.
FIG. 35.
[Illustration: A, _corpuscles of human blood, highly magnified;_ B,
_corpuscles in the blood of an animal (a non mammal)._]
THE BLOOD is the liquid by means of which the circulation is effected. It
permeates every part of the body, except the cuticle, nails, hair, etc.
The average quantity in each person is about eighteen pounds. [Footnote:
It is difficult to estimate the exact amount, and therefore authorities
disagree. Foster places it at about one thirteenth of the body weight.] It
is composed of a thin, colorless liquid, the _plasma_, filled with
red disks or cells, [Footnote: There is also one white globular cell to
every three or four hundred red ones. The blood is no more red than the
water of a stream would be if you were to fill it with little red fishes.
Suppose the fishes to be very, very small--as small as a grain of sand--
and closely crowded together through the whole depth of the stream; the
water would look quite red, would it not? And this is the way in which,
blood looks red--only observe one thing; a grain of sand is a mountain in
comparison with the little red fishes in the blood. If I were to tell you
they measured about 1/3500 of an inch in diameter, you would not be much
wiser; so I prefer saying (by way of giving you a more perfect idea of
their minuteness) that there would be about a million in such a drop of
blood as would hang on the point of a needle. I say so on the authority of
a scientific microscopist--M. Bouillet. Not that he has ever counted
them, as you may suppose, any more than I have done; but this is as near
an approach as can be made by calculation to the size of 1/3500 part of an
inch in diameter.--JEAN MACE.] so small that about three thousand five
hundred placed side by side would measure only an inch, and it would take
sixteen thousand laid flatwise upon one another to make a column of that
height. Under the microscope, they are found to be rounded at the edge and
concave on both sides. [Footnote: By pricking the end of the finger with a
needle, we can obtain a drop for examination. Place it on the slide, cover
with a glass, and put it at once under the microscope. The red disks will
be seen to group themselves in rows, while the white disks will seem to
draw apart, and to be constantly changing their form. After a gradual
evaporation, the crystals (Fig. 36) may be seen. In animals, they have
various, though distinctive forms.] They have a tendency to collect in
piles like rolls of coin. The size and shape vary in the blood of
different animals. [Footnote: Authorities differ greatly in their estimate
of the size of the disks (corpuscles) in human blood. The fact is that the
size varies in different persons, probably also in the same individual.
Many of the best microscopists therefore hesitate to state whether a
particular specimen of blood belonged to a human being or to an animal.
Others claim that they can distinguish with accuracy. Evidently, the
question is one of great uncertainty. The following statement of the size
of the cells in different animals is taken from Gulliver's tables: Cat,
1/4404 of an inch in diameter; whale, 1/3100; mouse, 1/3614; hog, 1/4230;
camel, 1/3123; sheep, 1/3352; horse, 1/4800; Virginia deer, 1/5038; dog-
faced baboon, 1/4861; brown baboon, 1/3493; red monkey, 1/3396; black
monkey, 1/3530.] Disks are continually forming in the blood, and are
constantly dying--twenty million at every breath.--DRAPER.
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