MOTHER: And though one-eighth of the body is blood, yet it will _all_ pass through the heart in about the same time. HELEN: How wonderful! But I don’t see how all these little things in the blood, called cor´pus-cles, can get through the tiny, hair-like veins, which are so small. MOTHER: We can learn a useful lesson from them, and you would be pleased, I know, to watch them, if they were only large enough so you could. They seem to know just what they want to do, and where they ought to go. When the little veins are too small for more than one to go in at a time, they do not push or crowd one another. One row waits as politely as can be till the others have passed in, and then they follow. How wonderful it is to think of this river of life flowing round and round, and we feel nothing of it but the gentle tap, tap of the heart as it sends it bounding through every part of the body! Should it stop, we would die; for “the blood is the life.” PERCY: But how did people find out that the blood goes around as it does? MOTHER: A doctor in England, named Harvey, first discovered it. Before his time people thought air went around through the body in the arteries. Men have studied the subject since Dr. Harvey lived, and they keep learning more about it all the time. AMY: Does water go into the blood, mother? MOTHER: Yes; it very quickly finds its way there, and it is the same with strong drinks, such as beer and whisky. It only takes a very few minutes for anything we drink to get into the blood stream. The walls of the veins and arteries are governed by the nerves of our telephone system. They let just the right amount of blood flow through them all the time. When alcohol gets into the blood, it puts the nerves to sleep, and so too much blood goes into the little veins. You know a man who drinks has a red face. If he drinks a long time, his nose gets so red that it is called a “rum blossom.” This is because so much blood goes to his nose that it becomes large and red. Alcohol also makes the walls of the arteries weak, so they sometimes burst open and the person dies. Now that we have learned a few things about the blood, we must be careful what we give this care-taker of the body to eat. We have learned very little of what there is to know, and as you grow older I hope you will study and learn more. THE BATHROOM HELEN: I have been thinking of what you said about the blood being washed every time it made a trip to any part of the body. Where is the bath room in the body-house, mother? MOTHER: It is a large double room, and it is found in the top part of the trunk, each side of the heart. PERCY: Why, I thought that was where the lungs are. MOTHER: So it is; and it is in them that the blood is made clean after every journey it takes through the body. AMY: But is there water in the lungs in which to wash the blood?