CLEANLINESS OF THE SKIN.

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12. It is not sufficient to follow the example of too many boys and girls, and I am afraid children of an older growth—merely to put a little water on their hands and faces; many children would like to run off to school without doing even that: but that part of our bodies covered by clothing must be kept clean, as well as our faces and hands, if we wish to preserve our health, our life, and happiness.

13. All children can do this themselves, without troubling their parents; and if they will do it, I can assure them that they will each have a longer life and more enjoyment; for if the particles are suffered to remain on the skin we cannot breathe so well, and of course would soon become diseased.

14. If the windows of a house should never be washed, they would soon become nearly useless, and would give us very little light or pleasure. If the paint and shingles were never repaired, the house would soon fall to decay, and be unfit for us to live in; so it would be as bad, and even worse for our house—that is, our body-if we did not repair or clean what has been called the shingles of our house, that is, the skin. The nails and hair are appendages to the skin; the nails are formed by little layers of thin skin, and serve to protect the ends of the fingers.

15. The hair is for a covering to the skull, each hair having a little bulb or root which has a nerve of sensation. Some say that the coloring matter is contained in

12. Will it not be sufficient to wash our hands and faces only? What depends on the cleanliness of the skin? 13. Who can relieve parents of this trouble? What will be the good results? 14. How can we apply the principle to the windows and paint of a house? What are the nails and hair called? 15. What purpose does the hair serve?

this little bulb; others, that it passes through the little tube in each hair. Sometimes the root decays, and then again the skin becomes diseased. In either case the hair falls off, and is dead, or has no life.

15. Has the hair any nerves? Where is its coloring matter? When does the hair fall off?

CHAPTER IV.

THE HEART AND LUNGS.

1. I WILL now tell you, children, about this curious heart of ours. You will recollect that you learned in my first lesson, that our food made blood. Suppose, then, we had bones, muscles, ligaments, skin, and stomach, but no vessel or receptacle to receive the blood when it was made.

2. Life, under such circumstances, could no more be sustained, than a steamboat could sail through the water of a thousand little streams, if it were not collected together in a river or bed of water. The heart is a double organ, and lies in the middle of the chest, with the point inclining to the left side, which gave rise to the idea that it was situated there.

The letter a is the left ventricle; b, is the right ventricle; c, e, f, is the great artery that proceeds from the left ventricle; g, h, i, are arteries that proceed from the great artery; k, is the artery that goes from the right ventricle to the lungs; 7, 7, are branches of the artery going to the two sides of the lungs, which carry the blood there; m, m, the veins which bring the blood back from the lungs to the left side of the heart; n, is the right auricle; o and p, are the ascending and descend

What is the subject of chapter fourth? 1. What do we need beside skin, bones, muscles, and blood? 2. What would be the result if there was no receptacle for the blood? Describe the heart and its situation. Explain the cut.

ing veins, which meet and form the right auricle; p represents the veins from the liver, spleen, and bowels; s, is the left artery, one which nourishes the heart.

3. The heart has four divisions: two to receive the blood after it is made from the food, called auricles; and two others, called ventricles, to send it to the several stations where it is most needed.

4. After the blood comes to the heart from the veins. it is necessary to send it to the lungs before it is fit for For this purpose there are muscles in the heart which contract and force it out to the lungs.

use.

3. How many divisions has the heart? What are they called? What is the office of the auricles? What is the office of the ventricles? 4. Where is the blood, that comes to the heart from the veins, sent? How is this accomplished?

5

5. Motion is of two kinds: voluntary and involuntary. That is voluntary, which is performed by means of the bones, muscles, and tendons, and is influenced by the will or mind.

Involuntary motion is that produced by organs not connected with the bones, but which possess muscular fibres; as, for instance, the stomach, which is a hollow muscle, and digests its food without the knowledge of the mind.

6. The heart is also a hollow muscle, which contracts and expands, to receive and send out the blood when necessary. It is protected by a bag called the pericardium, which is made of strong and rough materials. This case holds a very little water; just enough to permit the heart to move freely and easily, and is placed between the lungs.

water.

7. The lungs fill all that cavity in the chest, not occupied by the heart, and are composed of blood and airvessels. They are so light that they would float in the They are sometimes called bellows, because they contain so much air. They appear like the branches of a tree, and extend each side of the heart. When we take in a breath of air, we inhale it; when we throw out a breath we exhale it.

8. We inhale it, to change the color of, and to purify

5. What are the two kinds of motion? What is voluntary motion? What is involuntary motion? What is an example of involuntary motion? 6. How is the heart enabled to receive and send out the blood? By what is the heart protected? What does this case contain, and for what purpose? Where is the heart situated? Of what are the lungs composed? Where are the lungs situated? What is said of their weight? What are they sometimes called? What do they resemble in appearance? What is meant by inhalation? What is meant by exhalation? 8. What is the use of inhalation? What is the use of exhalation?