Part 21

HELEN: But, mother, I have heard girls say that their dresses were not a bit tight, when I am almost sure they were.

MOTHER: The only safe way is not to wear corsets or tight bands at all, and the clothing should be so loose that it will not compress the body when one draws a deep, full breath.

PERCY: I should think there was enough sickness in the world without people eating, drinking, and dressing to make themselves ill.

MOTHER: Many people do not know that it is what they do that makes them ill. They think people must be sick sometimes, and they do not study to know how to care for themselves in such a way that they may keep well. For this reason I wish you to learn how to care for the holy temple of your body while you are children, and we must also do all we can to help others by living right ourselves.

A PUMPING ENGINE

MOTHER: When we visited the water-works what did you admire most of all the things you saw, Elmer?

ELMER: The great engines that kept pumping all the time and never stopped to rest. How strange it seemed to think that they pump enough water for all the people in this great city! The houses on the hillsides as well as those on low ground have all they need.

MOTHER: But you would hardly think the house we live in has the most wondrous little pumping engine you ever saw, would you? Day and night it pumps “the river of life,” as the blood has been called, to every part of the body. If it should once stop, we would die, and the body-house could never be used again.

HELEN: Do you mean the heart, mother?

MOTHER: Yes. Can you tell me where your heart is?

AMY: I can. It is on my left side.

MOTHER: Not quite right, little girl. The lower point is felt on the left side, it is true; but most of the heart is higher up and nearer the center of your body. Who can tell how large it is?

PERCY: About the size of the fist of the person in whom it is found.

AMY: Then the baby’s heart is about as big as his dear little hand.

MOTHER: Can you describe its shape?

HELEN: I think it is something like that of a pear or a strawberry, with the small end down.

MOTHER: Here is a picture that will help us in learning its shape. I think I have not yet told you that the trunk of the body is divided into two large rooms. There is a partition running crosswise, called the di´a-phragm (di´a-fram). This gives us a large upper room, where we find the engine and bath room. The kitchen, eating room, store room, and waste rooms are in the lower part of the trunk, below the di´a-phragm. But we want to talk about the heart now. We have found about how large it is and what it is shaped like; let us next take a peep inside and learn, if we can, how it does its work.

ELMER: Didn’t you tell us once that the heart was made of muscles?

MOTHER: Yes; the outside walls are made of little strong muscles, and the inside is hollow. It is divided into four rooms. Each has its own name, but we will not try to learn them now. There is a wall reaching from top to bottom, and as it has no door, nothing can pass through from one side to the other. Then there are cross walls, or partitions, with folding doors in them, so there is an up-stairs and down-stairs room on each side. There are big pipes, or tubes, leading in or out from each room. They are called veins, or ar´ter-ies. The veins carry the blood to the heart, while the arteries carry it away.

HELEN: But, mother, what makes the heart beat?

MOTHER: I thought that would be about the first thing you would wish to know, and I will explain the best I can. When the muscles which make up the heart draw together, the rooms inside become small, and the blood in them is squeezed out. When the muscles slacken, the rooms become larger, and the blood rushes in and fills them again. So the blood keeps coming in and going out of the heart all the time, and it causes it to make the movement which we call beating.

AMY: How fast does it beat?

MOTHER: In very little children it beats from one hundred and twenty to one hundred and forty times a minute. In grown people it beats sixty or seventy times, and when the body-house has grown old and feeble, it beats slower still. Percy, you may run up and down stairs and then tell us if you see any difference in your heart-beats.

PERCY: I believe they are twice as many as they were when I was sitting still.

MOTHER: Hardly as many as that, but the heart beats much more quickly. Can you think of anything else that makes the action of the heart faster?

HELEN: When I was frightened this morning I could hear my heart go thump, thump, and I am sure it seemed to be in a hurry.

MOTHER: Yes; moving quickly, fright, anger, or joy makes this busy pump work more quickly. Sadness and grief cause it to work slowly. It beats faster when we are standing than when we sit still, and the motion is slower when we lie down than when we are sitting.

ELMER: Why did the doctor put his finger on my wrist when I was sick, mother?