hang a garment in the sunshine and wind to make it fresh and sweet. You
will remember that the blood takes oxygen, which is a part of the air,
to every part of the body-house, and this makes it warm. In exchange
the muscles give the blood a poison called carbonic acid gas. This
gives the blood a dark, purplish color, and it must carry away the gas
and get more oxygen before it can do any more work in mending the body.
PERCY: But I would like to know how it gets into the bath room.
MOTHER: The right side of the heart, which has nothing but soiled blood
in it all the time, sends it to the lungs in a hurry, and it fills the
thousands of hair-like veins which are in every part of the lungs.
The walls of the veins are so thin that the oxygen in the lungs soaks
through into the blood, and the poison in the blood goes through into
the air, and is breathed out of the body. Do you understand it now?
PERCY: I think so.
MOTHER: If I should tie a piece of bladder over a glass of milk and
place the glass in a bucket of water, the milk would come through into
the water, and the water would pass into the milk, even though they
were in separate dishes. Another way to show how the blood is cleansed
would be to say that blood and air keep running near together, each in
its own room, and as they pass they say, “Good-day;” air washes blood
so it becomes bright and clean, and blood makes air very dirty with its
poison gas; and, after trading in this way, both hurry along as fast as
they came in.
ELMER: It must be that good air is needed more than good food.
MOTHER: Why, yes; for while we need to eat only two or three times a
day, we must take in air more than twenty-five thousand times. If we
could not breathe for six or seven minutes, we would die, while we
could live without food quite a number of days. How thankful we ought
to be for pure, fresh air! And there is so much of it that we can have
it without money and without price.
HELEN: Which is best, to breathe through the nose or the mouth?
MOTHER: Through the nose; for that was made for the air to pass
through. Serious sickness of the throat and lungs is sometimes caused
by breathing through the mouth. When the air goes this way, the person
makes a very strange noise when asleep. The air seems to be trying to
wake somebody up to shut the folding doors so it can go the right way.
We call it snoring.
PERCY: I should think when there are so many people and animals, and
all must have air to breathe, that it would soon become unfit to use.
MOTHER: We live in an ocean of air, as fishes live in the sea. The
winds sweep it round and round, and everything that grows helps to make
it pure.
[Illustration: “_As fishes live in the sea._”]
AMY: How can that be?
MOTHER: It may be said that plants breathe, as well as people, only
they need the poison gas we breathe out, and they give out the oxygen
we need to breathe in. There is no danger but we can get all the air we
need if we will let it into our rooms.
ELMER: But isn’t night air bad to breathe, mother?
MOTHER: No; for when it is night we can get nothing but night air.
It is true that if air is shut up in a room it soon becomes unfit to
breathe, whether it is night or day.
PERCY: On frosty mornings my breath looks like steam as it comes out.
Is that the poison gas, mother?
MOTHER: No; we can not see the gas, but what you see is the water we
breathe out. We take in about a pint of air at every breath, and it is
said that every time we breathe out we spoil half a barrelful of air,
making it unfit to breathe. I will let you find out how many barrelfuls
of fresh air we would need in an hour.
PERCY: Why, that would be over five hundred barrels! Who ever thought
that we needed such a lot of fresh air in just one hour!
MOTHER: And who, then, would think of using only one roomful in a whole
night! It is no wonder that many people have a headache when they wake
in the morning.
HELEN: But, mother, we can’t get clean air always, even when we are not
in the house. This very day a man puffed tobacco smoke into my face as
I was passing him.
AMY: But do you think it is _right_, mother, for any one to poison the
pure, fresh air God has given us, with tobacco smoke, and make it unfit
to use?
MOTHER: No; I do not; and a true gentleman will not do it. It is both
rude and wrong. He not only wrongs others but harms himself. You know
how it feels to get smoke into your eyes, and it is just as bad for
the throat and lungs. Bad smells of any kind poison the air, making
it unfit to breathe, so we should be careful to keep our rooms and
everything about the house sweet and clean.
PERCY: I met a man in the street, and I could smell the whisky he had
drunk. Did that come from his lungs?
MOTHER: Yes; just as soon as strong drink is swallowed, every part of
the body tries to get rid of it. The alcohol in such drinks makes the
thin walls of the lungs hard, so they can not make the blood clean, and
they try to throw out the poison. Sometimes it causes that dreadful
disease, consumption, which can not be cured.
HELEN: Don’t a great many people die of consumption?
MOTHER: Yes; it kills more people than any other disease; so every one
should take good care of their lungs, and give them plenty of room to
grow. They should also breathe pure, fresh air at all times.
ELMER: But you can’t squeeze the lungs. We must have room to breathe.
MOTHER: But we can squeeze the stomach and liver so that the lungs do
not have room, and by stooping over when sitting or walking, we get
round shoulders and narrow chests, and this causes the lungs to become
small and diseased.
AMY: I once read how some people on a ship suffered for fresh air.
MOTHER: Please tell us about it.
AMY: One night when there was a storm the captain told the sailors to
send the people down into a large room below deck so they would not be
in the way. After they had gone, the doors were fastened, so they could
not get out. When the storm was over, the sailors took a candle and
opened the door, but when they went in, the candle went out. At last
enough fresh air got in so the candle would burn. They found the poor
people lying on the floor, and quite a number of them were dead.
MOTHER: I suppose they had no air to breathe only that which had been
used over and over again, and as that was not fresh, it poisoned them
so they died. We should learn from this sad story to keep the lungs
well filled with good air; for the blood can not be well cleansed if it
is impure.
HOW THE HOUSE IS HEATED
MOTHER: If you touch a stone, Amy, how does it feel?
AMY: It is cold.
MOTHER: Yes, wood, iron, glass, and all the things around us which do
not have life, are cold. If you touch your head, how does it feel?
PERCY: It is warm.
MOTHER: We sometimes see a little glass tube called a thermometer, with
figures telling us how warm or how cold the air is. Here is a smaller
one that you may hold in your mouth under your tongue, Elmer, and we
will see if it will tell us how warm the house you live in is inside.
That will do. The glass says it is about ninety-eight degrees. How many
degrees will the larger glass record on a hot summer day?
ELMER: It is very warm when it is over eighty or ninety in the shade.
MOTHER: Yet you see that inside the body-house it is nearly one hundred
degrees, yet you do not feel too warm. Are all animals warm?
HELEN: If they are alive, they are. If their bodies are cold, we say
they are dead.
MOTHER: Some birds and animals have more heat in their bodies than we
do. The horse has one hundred degrees, the ox one hundred and one, the
dog one hundred and two, the sheep one hundred and four, and the duck
and pigeon have one hundred and eight. The bodies of some creatures,
such as fishes and frogs, are much cooler than our own, and we call
them cold-blooded. The frog has only seventy degrees of heat.
[Illustration: _Fever thermometer._]
HELEN: But what makes us warm, mother?
MOTHER: Do you remember that we talked a good deal about our food as
fuel not long ago?
PERCY: But, mother, fuel is something to _burn_, and there is no fire
inside of us.
MOTHER: That is true in one way; but let us see if we can find out
where the heat in our bodies comes from. It may be a little hard to
understand, but we will try. Here is a candle. If lighted, it burns
brightly. Now I will fasten a wire around it and lower it into this
glass jar and cover it tightly. Now watch it. What is the matter?
[Illustration: “_Now watch it._”]
AMY: It is going out. Now it just flickers and hardly burns at all. Why
does it go out, mother?
MOTHER: Because all fire must have a part of the air called oxygen
to make it burn. When the candle can have plenty of air, it burns
brightly, but when shut up closely, where it soon uses all the oxygen,
it will not burn at all. Now our bodies are much like the candle. We
eat food, and when it is made into blood, it mixes with the oxygen we
breathe, and as it goes round and round in the body, it makes heat. The
difference between us and the candle is that the burning does not go on
as fast in our bodies as in the candle, so there is no flame, and it
would take much longer to make the same amount of heat. If you throw a
piece of fat into the fire, it will burn. If you eat the fat, it will
make just as much heat in your body, but it will last a long time.
PERCY: How queer to think we are burning, bit by bit, just like a
candle!
MOTHER: Yes; just as long as we live, the fire is kept going.
AMY: But I shouldn’t think that blood going around with oxygen in it
would keep us warm.
MOTHER: If that was the only way to heat the body, it would not. Where
it is very cold, some houses have a grate; there may also be a furnace,
and perhaps a stove besides. So there are three ways of heating the
house we live in. The first, as I have told you, is by the blood
carrying oxygen to every part of the body. That is like the grate. We
will call the liver the furnace. We have found that all the starch and
sweet things we eat are changed into liver sugar, and it is supposed
this is used in the lungs to keep the body warm.
HELEN: In what other way is the house heated?
ELMER: I think I know. It is by exercise. When I run or play ball I
become very warm.
[Illustration: Frogs]
MOTHER: Yes, when we move quickly, we breathe faster, and the blood
goes bounding through every part of the body, so the fire inside burns
brightly. Sawing wood is a good way to warm a cold boy, and a broom is
a fine helper to warm a cold girl.
AMY: When it is frosty, we can see our breath. Is that the _smoke_
coming from the fire inside, mother?
MOTHER: You may call it that if you like. When a candle burns, it gives
off what we call carbonic acid gas, and we breathe out some of the same
kind of gas. Water also comes out in the breath like steam from an
engine, half a pint or a pint each day.
ELMER: Do some kinds of food make more heat than others?
[Illustration: “_A good way to warm a cold boy._”]
[Illustration: “_A fine helper to warm a cold girl._”]
MOTHER: Yes; all kinds of fatty foods make heat. In very cold countries
people can eat more fat and keep well than in warm climates. Esquimaux
eat a great deal of fat. A little Esquimau child would eat a tallow
candle and enjoy it as much as you would an orange. I once read of
some sailors who made a Christmas tree for some of those children in
the frozen north. The tree was made of walrus bones tied together,
and, instead of popcorn, fruit, and sweetmeats, they hung balls of fat
on the tree. The children thought it a great treat, and ate them as
quickly as you would eat peaches.
AMY: How funny! But, mother, are not our bodies warmer in summer than
in winter?
MOTHER: You _feel_ warmer, it is true; but, no matter how hot or cold
the weather may be, the body has always about the same warmth. I said
_always_, but I mean when we are well. Sometimes we put the wrong kind
of fuel into the furnace, and it makes a big fire, the house gets very
hot, and we say we have a “fever.” If we get two or three degrees
cooler than we should be, that shows that something is wrong, too.
HELEN: But what keeps us the same whether it is hot or cold?
[Illustration: “_We have a ‘fever.’_”]
MOTHER: You know some stoves have dampers to govern the heat. When the
body is in danger of becoming too warm, that is, when the body is well,
all the little waste-pipes in the covering of our house pour out water
so the skin is damp or moist, and if very warm it is wet. We might say
we have thousands of little “dampers” to keep the heat just right.
As the sweat dries, the body becomes cool; so in summer and in hot
climates the people sweat much. In winter and in cold countries they
perspire but little, and the tiny waste-pipes close as tightly as they
can to keep the cold out and the heat inside.
PERCY: But when I had a cold my skin was hot and dry. Why did not the
little dampers make me cool, then?
MOTHER: Because they were clogged so they could not. After a warm
foot-bath and a hot lemon drink, you began to sweat and soon became
well. If nothing had been done to open the waste-pipes, you might have
had a serious illness.
ELMER: Does alcohol make the body warm? I once heard a man say it was
so cold that he must take something to keep him from freezing, as he
had a long journey before him.
MOTHER: I am sure he did not know the effect of wine or alcohol or he
would not have said that. When first taken, these stimulants drive the
blood to the skin, and we _feel_ warmer; but soon the blood goes back,
after being chilled, and the whole body becomes colder. No, alcohol
in any of its forms will not “keep out the cold,” as people sometimes
think. Men in frozen countries endure the cold much better when they
take no strong drink of any kind.
HELEN: I once read of a party of twenty-six men who lost their way as
night came on. It was very, very cold, and they had no way of making a
fire. Each man had two blankets and plenty of food and whisky. Their
leader told them to let the whisky alone; to eat supper, and then wrap
up in their blankets and lie closely together. But only two besides
himself did as he said, and, though they were cold, they did not suffer
or freeze. The others thought the whisky would keep them warm. Three
drank a very little, and they did not freeze. Seven others, who drank
more, had their toes and fingers frozen. Six, who drank still more,
were so badly frozen that they never got over it. Four, who became
drunk, were frozen so that they soon died; and three, who drank so
much that they became “dead drunk,” were dead in the morning.
MOTHER: That was surely a good test, showing how much alcohol can do
toward keeping the body warm.
PERCY: Why do we need clothes to keep us warm? The birds and animals
don’t wear any?
[Illustration: “_Birds have a cloak of feathers._”]
MOTHER: I think they do. The birds have a cloak of feathers, which
they puff out to keep them warm when it is cold. The horse and cow
have coats of hair. The sheep has a thick woolen dress. Animals living
where it is very cold have warm suits of fur. Our skin is not covered
as theirs is, and our bodies would lose much heat if exposed to the
air. Food makes heat, and our clothes keep us from losing it. We need
clothing to keep us warm.
HELEN: But people do not need clothing in warm countries.
MOTHER: And they do not wear much; but we would need it if there, to
keep the hot sun from scorching the skin. We should never wear heavy
clothing, and it should be made so loose that it will not hinder the
growth or movements of the body. The shoulders should carry its
weight. When the warm days of spring come, it is not best to be in a
hurry to leave off our warm under-clothing. Many persons have died
because of doing so.
AMY: Should our clothes be changed often?
MOTHER: At least those worn next the skin should be, in order that we
may keep neat and clean. Clothes worn in the daytime should not be worn
at night, and nightclothes and bedclothes should be kept fresh and well
aired. If the clothing we are wearing gets wet, it should be changed at
once. Never wear wet shoes or stockings or wet clothing of any kind.
Which part of the body do you think should have the warmest clothing?
AMY: The part farthest from the heart; for that would get colder than
any other.
MOTHER: Yes, the limbs should be warmly clad; for the blood often gets
chilled before it reaches the fingers and toes, and that is why they
get cold sooner than do other parts of the body. Yet I have seen many
little boys and girls with warm coats and furs around the chest, where
there is the most heat, and a part of the tender limbs had no clothing.
That is like trying to keep the furnace warm, and letting the rooms
farther away have no heat at all.
PERCY: I should think children dressed in that way would be ill.
MOTHER: Many of them are. They often have bad colds, and sometimes the
lungs get so much blood, because it is chilled away from the parts
to which it should go, that they can not do their work properly; the
throat becomes sore, and the poor child may lose its life because the
mother did not know how to dress it. Your father, though he is a strong
man, would suffer if clothed in that way. Let us see if we can not make
some good rules for clothing the body.
ELMER: I will make the first, which is, Wear loose, light clothing.
AMY: Then don’t be in a hurry in the spring to change warm clothes for
those that are cooler.
HELEN: We should keep all our clothing neat and clean.
PERCY: That which is worn in the daytime should not be worn at night.
AMY: That makes me think of another: Nightclothes and bedclothes should
be fresh and well aired.
ELMER: And we should change our wet clothes for dry ones.
PERCY: The limbs should be as warmly dressed as any part of the body.
MOTHER: Well done. I think these are all good rules. Let us see how
well we can keep them.
THE MUSIC ROOM
MOTHER: Do you think of any musical instruments which need air when
they make a sound?
PERCY: The cornet, flute, and horn.
AMY: And the organ, too.
MOTHER: Yes; all of these and others as well must have air to make
sound. But I wanted to tell you that in the wonderful house we live
in there is the most perfect organ you can imagine. I am sure there
is none like it, none that can make such sweet music, and I have seen
many, and heard the largest pipe-organ in the world.
HELEN: Where can it be?
MOTHER: And it not only makes the finest, sweetest music, but it can
laugh and talk. Sometimes its tone is soft and sweet, but it can be
made loud and harsh if the master wishes. This curious little organ has
a room all to itself, and--
ELMER: Do you mean the voice?
MOTHER: There! you guessed it the first time.
AMY: Where is the organ, mother?
MOTHER: In the top of the windpipe, in the throat. It is really a part
of the windpipe itself, and this curious little room has walls at the
sides, but no floor. The little trap-door which keeps food from going
to the bath room forms the top of the music room.
PERCY: How large is it?
[Illustration: _Cornet._]
MOTHER: It is larger in men than in women, and you can see the front
part in a boy’s throat. Sometimes it is called “Adam’s apple.” I once
read that perhaps the reason it has this name is because when Adam was
eating his apple he was in such a hurry to blame Eve for giving it to
him that a quarter stuck in his throat. We know that he laid the blame
on Eve for his eating the forbidden fruit, but whether it was apples or
some other kind of fruit I do not know, so you need not believe this
story.
ELMER: But I would like to know what causes all the different sounds
which are made by the voice.
MOTHER: I will try to make it as plain as I can. Near the top of this
room two cords are stretched across from front to back. These cords
stretch like India-rubber, so they can be made tight or loose. There
is an open space between them, where the air can pass through, but the
other space is filled up. Did you ever see the little piece of brass in
an organ called a “reed”?
[Illustration: _Flute._]
HELEN: I saw one when our organ was cleaned.
MOTHER: Here is a picture of one. You see it has a little tongue, and
when air is blown through the opening in the reed, the tongue vibrates,
that is, it goes up and down so fast that you can hardly see it, and
this makes the sound. The smaller the tongue, the faster it will
vibrate, and the tone will be higher.
AMY: But how is it that we can speak and sing low or high?
MOTHER: Our lungs are like the bellows of the organ, and the voice
cords are like the reeds. When the master of the body wants to speak
low, he sends an order to some muscles in the throat to let the cords
hang loose. If he wishes a high tone, he tells them to stretch the
cords tight. If he would make no sound, the cords hang loosely, and the
air passes between them without making any sound.
[Illustration: _Organ reed._]
[Illustration: _Organ._]
ELMER: How strange that, with only two cords, we can make nearly all
tones made by the piano, which has so many!
MOTHER: That shows how much better God can make anything than men
can. Perhaps the violin is more like the voice; for it can make more
tones on fewer cords; but, though it can be made to produce very sweet
sounds, it can not be compared to a trained voice, which can speak
words and make music at the same time.
HELEN: I’m glad I can talk and sing.
MOTHER: The voice is a gift of God. How we pity a person who is dumb!
Every one should learn to speak in a clear, gentle voice. A harsh
word wounds the one to whom it is spoken; and the tone often strikes
deeper than the words. We have all felt soothed and comforted by kind,
pleasant words. All who can should learn to sing.
“If you have a pleasant thought,
Sing it, sing it;
Like the birdies in their sport,
Sing it from the heart.”
“It is not so much what you say,
As the manner in which you say it;
It is not so much the language you use,
As the _tones_ in which you convey it.
“‘Come here,’ I sharply said,
And the baby cowered and wept;
‘Come here,’ I cooed, and he looked and smiled,
And straight to my lap he crept.
“The words may be mild and fair,
And the tones may pierce like a dart;
The words may be soft as the summer air,
And the tones may break the heart.
“For words but come from the mind,
And grow by study and art;
But the tones leap forth from the inner self,
And reveal the state of the heart.
“Whether you know it or not,
Whether you mean or care--
Gentleness, kindness, love, and hate,
Envy, and anger are there.
“Then, would you quarrels avoid,
And in peace and love rejoice,
Keep anger not only out of your words,
But keep it out of your voice.”
THE HEARING PASSAGE
MOTHER: While we have but one voice room, we have two hearing rooms or
passages, and they are the most wonderful of any you ever did see. One
is placed on each side of the head.
ELMER: Those are the ears, I know. Please let us send a sound through
them, mother, and you tell us what it finds.
MOTHER: Very well; and we will suppose this sound has eyes as well as a
tongue, and it will tell us what it sees. Now listen:—
All sounds are made of such tiny waves, so very, very small, that you
can never see them, yet they are something like those you see when you
throw a stone into the pond. The first thing a sound finds when it
wishes to visit the master of the body-house, is a pretty porch just
outside of the passage made for it to enter.
AMY: What does it look like?
[Illustration: “_Something like a shell._”]
MOTHER: Something like a shell, and it is a pretty, pale pink color. I
suppose it was made this shape so it can catch and hold sound; for I
have seen some people living in old houses put up their hand to make
the porch larger so they could hear better.
PERCY: I have often seen grandfather do that, but I never knew why
before.
MOTHER: Each sound finds a little door, which always stands open, and,
though it is very small, the sound finds no trouble to get inside. This
part of the passage is covered with sticky yellow wax, which is there
to keep out anything which should try to go in except different kinds
of sounds.
ELMER: How long is the passage?
MOTHER: Only about an inch, and it seems quite like a tunnel dug in a
rock, only this is made in bone instead of stone. At the end there is a
round curtain, which is drawn close and tight, like the head of a drum,
so nothing but sound can get through.
PERCY: But what I would like to know is how the sound can get inside.
MOTHER: Oh, there is nothing hard about that! It may seem quite like a
fairy story, but all it has to do is to knock, and then it is on the
other side.
HELEN: How strange! And what does it find there?
[Illustration: Ear bones]
MOTHER: Things you would never expect to see, I am sure: First, a
hammer, that strikes with its handle end on the curtain, or ear-drum,
as soon as sound gives a knock, and with the other end it strikes a
little anvil, and the anvil kicks against a tiny stirrup. Here is a
picture of them. They are all made of bone.
ELMER: Well, this beats anything we have heard yet.