MOTHER: Yes; and since the brain is such an important part of the body, it is put in the strongest room of all. It sometimes becomes ill if not used right, so we should learn how to keep it well. The worst sickness in the world is mind sickness, and it is hardest to cure. The brain has six coverings in all. The outside coverings are the hair and scalp, or skin. Then we find the strong bones, fitted closely together with saw-teeth edges. Inside the bones the brain has three coverings: first, a tough, strong skin; then a very thin covering, hardly thicker than a spider’s web; and the third is made up of many little blood-vessels, which feed the brain. AMY: I wish we could see how the brain looks, mother. PERCY: I have seen brains at the butcher shops. Do ours look like that? MOTHER: Yes, quite the same. You have all seen the marrow in the bones. The brain looks some like that, too. It is made of jelly-like matter, and seems to be all crumpled up, so it is full of ridges and creases, as you see in this picture. It is said a baby’s brain is quite smooth, but the more a person thinks, the more ridges and furrows his brain will have and the deeper they are. A frog’s brain is smooth, like this. [Illustration: _The brain is full of ridges and creases._] [Illustration: “_A frog’s brain is smooth._”] ELMER: But I don’t see how the brain thinks. MOTHER: That is one of the things we can never understand. God gave men life, and when we are alive we think. “In Him we live, and move, and have our being,” and to be able to think is one of the best gifts that comes with life. It is the life God gives us which makes the body-house worth more than the most costly palace in the world. If we look carefully into the brain, we see that the outside is gray, and the inside is white. Wise men tell us this matter is made of cells, called nerve cells, or brain cells. The gray matter tells the muscles what to do, and the white part sends the orders to all parts of the body through the nerves. ELMER: Have we more than one brain, mother? MOTHER: I might say no, and yes. It is really one, and yet it is in several parts. One is the big brain, which is found above the ears in the top of the head. It is with this part we think and reason. Then there is a little brain, in the back part of the head under the large brain. It is about as big as a medium-sized orange. Each brain has two parts, a right and left half, so we really have two brains. It might be said we are “left brained” when we are “right handed,” for the right hand is ruled by the left half of the brain. AMY: How large is the brain, mother?