By and by the clock strikes eight or nine, and your mother says, “Children, time to go to bed!”

Sometimes you will have just come to the interesting point in the story, and would give anything to go on and finish it. But often you will be just nodding over your book, or beginning to wonder why the story is not quite so interesting as it was, or why the lines seem to be running into one another, and the book inclined to swing up and bump your nose.

If you have had a lively, busy, happy day, you are quite sleepy enough to be ready for bed—that is, if you could drop into it with all your clothes on, without all the bother and fuss of undressing. So you pull yourself together bravely and answer, “All right, mother,” and say “Good night” to everybody, and upstairs you go.

Of course, you must take off your clothes, because you would find them most uncomfortable to sleep in. Besides, the little pores all over your skin have been pouring out perspiration all day long; and a great deal of this has been caught by your clothes, just as it is caught by the bedclothes while you sleep.

So it is a good thing to take off your clothes, and let your skin be well aired and cooled. Don’t leave your clothes all in a heap on the floor just where you happen to shed them, but hang them up over the back of a chair or on pegs, so that the air can blow through them all night long and sweeten and clean and dry them. Clothes that are worn continuously become sour with perspiration, and for this same reason your mother gives you regularly, once or twice a week, clean underwear and clean shirts or dresses.

After you have undressed for bed, wash your face and neck and hands; and if you have a nice warm room or bathroom, take a quick splash, or sponge bath, all over, before you put on your nightgown. This will wash away from your skin everything that the perspiration has been leaving on it all day long, as well as any dust, or dirt, that may have got on it during the day.

If the room is not warm enough for you to do this, it is a good thing for you to strip to your waist and then to swing your arms about, much as you did in the morning, only not quite so long, and to rub your arms and neck and shoulders all over with your hands. This gives them an air bath, and rubs off any of the little scales of skin that may be ready to be shed, and gives you a sort of dry wash, which is next best to a wet one.

Then, when you have put on your nightdress, give your hair a thorough brushing. This is the best time of the day to do it. Dust, smoke, soot, and germs have been blowing into your hair all day long, and a thoroughly good brushing will not only get these out of it before they have had time to work their way in and lodge on the scalp, but will keep the hair bright and healthy.

Before you get into bed, give your nails a quick scrub with a nail brush and hot water and soap, and go over them with a blunt-pointed nail cleaner, cleaning out any dirt that may be under their edges, and rounding off any ragged or broken points with the file. Once a week or so, when you take your hot bath, it is a good thing to go over your toe nails in the same way, trimming them and cleaning them. Remember, however, not to round off your toe nails at the corners, but to leave them square, as in this way you will prevent them from ingrowing under the pressure of your shoes.

There is one thing that you should be very sure of before you get into bed, and that is that your teeth are as clean as it is possible for you to make them. If you attended to this also directly after supper, so much the better; for just as it is important to clean the dishes and knives and forks that you have been using, so it is important to thoroughly clean the ivory knives and forks that grow in your mouth. Talk about being “born with a silver spoon in your mouth”! You were born with something much prettier and far more valuable.

Even though your teeth make a firm and even line in front and on their cutting edges, yet there are many little gaps and spaces between their roots, where bits of food can stick. If these scraps of food are not thoroughly and carefully removed after each meal, the warmth and moisture in the mouth makes them begin to decay. The acids from this decay will be likely not only to upset your stomach and digestion, but to act upon the glassy coating of your teeth. After a little while, spots will begin to form on the surface of your teeth; they will lose their bright, shiny, pearly look; the acids will eat further into the teeth, and very soon there will be holes, or cavities.

Though your teeth are very hard and glassy looking on the surface, they are much softer and chalkier inside; this glassy coating covers only the crown, or free part, of the tooth, which you can see. It leaves the softer inside part of the tooth bare just at the edge of the gums, and particularly between the roots of the teeth, where little scraps of food lodge and decay. When the acids that are formed by the decaying food have eaten away a good deal of the inside of the tooth, the hard, shiny surface is left just like a thin shell; and one day you happen to bite down upon a piece of bone in your food, or try to crack a nut with your teeth, and “crack” goes this brittle shell of your hollow tooth.

Right in the middle of each tooth is a tiny hollow, or cavity, filled with a soft, living pulp containing one or two very sensitive nerves; and when the decay has eaten into the tooth far enough to reach this nerve pulp, it makes it ache, and then you have toothache.

The one and only thing that is necessary in order to avoid all this decay and breaking away of your teeth, and throbbing toothache, is to keep the surface of your teeth, and particularly the sides where they are next one another, clean and smooth and unbroken. And all that is needed to keep your teeth perfectly clean and smooth is to use your toothbrush thoroughly after every meal and at bedtime; and then, if there are any little scraps of food between the teeth that have not been brushed away, to pick them out gently with a quill toothpick, or take a piece of silk or linen thread, push it up between the teeth, and gently saw backward and forward until you have cleaned out the space between the roots. You should take at least three to five minutes after every meal and before you go to bed at night to brush your teeth; and you should brush not only your teeth, but the whole surface of your gums close up to where they join the lips.

It is almost as important to keep your gums pink and hard and healthy as it is to keep your teeth clean; and the same thorough brushing will do both. If the gums are perfectly healthy, they will come well down over the roots of the teeth, and keep them safely covered right down to where the glassy outer coating begins, and so leave no gap where the acids of decay can attack the teeth. Be sure to brush your teeth, not merely straight backward and forward, but up and down and round and round as well, both to clean out thoroughly all the grooves and openings between them and to brush the gums well down over the teeth.

It may seem strange, but one of the best ways to keep your teeth from growing crooked and irregular is to keep your nose clear and healthy, so that you can breathe through it freely at all times, both day and night. Crooked jaws and irregular teeth are more often caused by mouth breathing than by any other one thing.

You can see why it is best to be careful not to get grit or dirt or bits of bone in your food, and not to crack nuts or hard candy with your teeth. If you do, you may crack or scratch the delicate glassy coating of your teeth. But, on the other hand, it is a good thing to give the teeth plenty to do, and particularly to eat the crusts of bread, and some of the tougher parts of meat, and parched corn or other grains, and to eat celery, apples, and other foods that take a great deal of chewing. The teeth are like everything else in the body—they need plenty of vigorous work in order to keep them healthy.

Be very careful, though, to keep out of your mouth anything that might possibly crack or scratch the glassy coating, such as pins, pennies, pieces of wire, or slate pencils. It is best not even to try to bite off threads or pieces of string. There is, of course, another reason for not putting pencils and pennies and such things into your mouth: they may have dirt, or germs, on them and infect you with disease or at least upset your digestion.

II. THE LAND OF NOD

Now you are all ready for bed; and the white pillow and the nice, clean sheets and the warm blankets look very good to you, and you are ready to go to the “Land of Nod.”

You need not be afraid of the cold at night. Open your bedroom windows. Have plenty of light-weight, warm covers; then the cold breezes won’t hurt you, but will make you strong. Just think how many hours you are in bed,—nearly half of your life,—and you need fresh, moving air all the time. Be sure to open your windows from the top as well as from the bottom. You know why: your breath is warm so that it floats and rises like smoke; and if you open the window only at the bottom, this bad air, which rises to the top of the room, can’t get out. It is best to have windows on two sides of a bedroom, so that the air can be kept moving through it all night long. If you don’t breathe fresh air while you sleep, you will feel dull and stupid in the morning and perhaps have a headache.

So run your window shades right up to the top and throw your curtains, or shutters, back, as well as open the windows. If you don’t, the fresh air cannot blow through the room properly. Even if this does let more light or noise into the room, this is of no importance whatever compared with abundance of fresh air. If you have played long enough out of doors in the daytime and have eaten a good supper and not stayed up too late, you will sleep soundly without being bothered at all by either lights or noises coming in through the windows. And no matter how cold or how light it is, don’t put your head under the bedclothes. Why?

It is best for you to close your mouth while you are going to sleep, and breathe through your nose, so that the air will be properly purified and warmed before it reaches your lungs. If you can’t do this, your mother can perhaps give you something to wash out your nose, so that you can breathe freely. If that does not help, you had better see a doctor, and he will find some way to clear your head so that you can use your nose comfortably.

Suppose you take a pencil and paper and write down all you did yesterday. Wasn’t it enough to make you tired and sleepy and want a chance to rest? Even while you sleep, your heart keeps beating, and you don’t stop breathing, of course. But your muscles are quiet, and your food tube rests. Your brain rests, too,—better in sleep than at any other time,—so that when morning comes you are as “lively as a cricket” and quite ready for the new day.

Yet even in sleep your brain does not stop working entirely, but goes on receiving messages from the stomach and the skin and the memory, and mixing them up together in the strangest fashion, so that you dream, as you say. You ought not to dream very much if you are perfectly well; but as long as your dreams are pleasant or amusing, you need not pay any attention to them. But if you have had bad dreams, or you dream so hard all night long that you don’t feel rested in the morning, then you had better speak to your mother about it, and let her see what is the matter with your digestion or your nerves, or take you to a doctor. Bad dreams are always a sign of ill health and are a very disagreeable thing, from which there is no need that you should suffer any more than from headache or indigestion or colic. Dreams, of course, do not mean or foretell anything whatever, except simply how bad, or good, the state of your digestion and your nerves is.

Now, how much time should you spend in bed? Well, I think at your age nearly half the time. Ten or eleven hours of sleep make you ready for all the hours of work and play, and you don’t become cross and tired half so easily if you have plenty of sleep. Though you are lying so quietly, you are not by any means wasting your time, for you probably are growing faster when you are asleep than when awake. Babies, who are growing very fast, you know, sleep nearly all the time.

So after you have opened all the windows wide, put out the light and jump into bed and lie down for a good night’s rest without thinking about anything except how comfortable the bed feels when you are tired.