The Childs Day | Page 9

in your skin very fast; and unless you are warmly dressed, you become chilled.
When you are chilled, you are using up, in merely trying to keep yourself warm, some of the energy that ought to be used for growing and for working. It has been found out by careful tests that children who are not warmly dressed, and particularly whose arms and legs are not warmly covered, do not grow so fast as they ought to, and more easily catch colds and other infections. So take time to put on your cap and your coat, if the weather is cold; and, if it is snowy, to button on leggings over your stockings; and then you can play as hard as you like, and run through the snow, and keep warm and rosy and comfortable.
Wool is one of the best stuffs for coats and dresses and stockings and gloves and caps, not only because it is warm, but also because it is lighter in weight than anything else you could wear that would be equally warm, and because it is porous; that is, it will let the air pass through it, and the perspiration from the body escape through it.
Don't wear any clothes so tight that you cannot run and jump and play and fling your arms and legs about freely, or so fine and stylish that you are afraid of getting them soiled by romping and tumbling.
It is best to wear fairly heavy, comfortable shoes with good thick soles; then you will not have to wear rubbers, except when it is actually pouring rain, or when there is melting snow or slush upon the ground. Felt, or buckskin, or heavy cloth makes very good "uppers" for children's shoes; but only leather makes good soles.
It is best not to wear rubbers too much, because the same waterproofness, which keeps the rain and the snow out, keeps the perspiration of your feet in, and is likely to make them damp. When they are damp, they are as easily chilled as if they had been wet through with rain or puddle water. Always take off your rubbers in the house or in school, because they are holding in not only the water of perspiration, but the poisons as well; and these will poison your entire blood, so that you soon have a headache and feel generally uncomfortable.
II. AN EARLY ROMP
The minute you are outside the door, the fresh morning air strikes your face, and you draw four or five big breaths, as if you would like to fill yourself as full as you could hold. If you have had a good night's sleep and a good breakfast, the very feel of the outdoor air will make you want to run and jump and shout and throw your arms about. This warms you up finely and gives you a good color; but if you keep it up long, you will notice that two things are happening: one, that you are breathing faster than you were before; the other, that your heart is beating harder and faster, so that you can almost feel it throbbing without putting your hand on your chest.
If you run too hard, or too far, you begin to be out of breath, and your heart thumps so hard that it almost hurts. What is your heart doing? It is pumping; it is trying to pump the blood fast out to your muscles to give them the strength to run with.
[Illustration: AN EARLY RUN IS A GOOD PREPARATION FOR THE DAY'S WORK]
Of course you have seen a pump? Perhaps some of you have to pump water every day at home. You take the handle in your hands, lift it up, then press it down, and out pours the water through the spout; and, as you keep pumping, the water spurts out every time you press the handle down. It is hard work, and your arms are soon tired; but, as you cannot drink the water while it is down in the well, you must pump to bring it up where you can reach it.
[Illustration: THE HEART-PUMP
The big tubes are the arteries and veins.]
Just so the heart pumps to keep the blood flowing round and round, through the muscles and all over the body. If you put your finger on your wrist, or on the side of your neck, you can feel a little throb, or pulse, for every spurt from your heart-pump; and that means for every heart-beat.
This heart-pump is made of muscle, and is about the size of your clenched fist. And just as you can squeeze water from a sponge or out of a bulb-syringe, by opening and shutting your hand around it, so the big heart muscle squeezes the blood out of the heart. It squeezes it out from