MOTHER: Only about an inch, and it seems quite like a tunnel dug in a rock, only this is made in bone instead of stone. At the end there is a round curtain, which is drawn close and tight, like the head of a drum, so nothing but sound can get through. PERCY: But what I would like to know is how the sound can get inside. MOTHER: Oh, there is nothing hard about that! It may seem quite like a fairy story, but all it has to do is to knock, and then it is on the other side. HELEN: How strange! And what does it find there? [Illustration: Ear bones] MOTHER: Things you would never expect to see, I am sure: First, a hammer, that strikes with its handle end on the curtain, or ear-drum, as soon as sound gives a knock, and with the other end it strikes a little anvil, and the anvil kicks against a tiny stirrup. Here is a picture of them. They are all made of bone. ELMER: Well, this beats anything we have heard yet. MOTHER: I don’t wonder you say so; for the wisest men, who have studied the body-house for years, say the ear is one of the most wonderful parts of the body. When boys or girls have two drums, two hammers, two anvils, and two stirrups in their heads, it is no wonder that it takes plenty of noise to make them happy. It makes me think of two little fellows I saw playing with a toy engine a few days ago. They had their mother’s knitting-needles in the smoke-stack, and as they dragged the toy over the floor, it made a fine jingle. The mother, however, wished to talk with a lady friend, and asked them to take out the needles, so they would not disturb her. “But it won’t make any n-o-i-s-e then,” said the older boy in a whining tone. I suppose the noise was a delight to all the tiny hammers and anvils in his ears; and it is much the same with every boy. But I forgot to tell you that there is a way to reach the inside of the ear without going through the ear-drum. AMY: Please tell us how. MOTHER: By going the same way that air takes to go to the lungs; you will find a little door just before you come to the music room, which leads to the ear. PERCY: But why should there be _two_ passages to get to the inside? MOTHER: For the very good reason that air is so heavy; if it should press against the ear-drum, it would break it, unless there was something to press just as much against the other side. So some nice, warm air goes up from the throat, and as it is just as heavy as the air outside, it makes the weight alike on both sides. I once heard of a girl who was asked how air could get inside of the drum of the ear, and she said, “Through the _other_ ear.” Her mates in school all laughed at such a thoughtless answer. You will now know better than to make such a statement if the question were asked you. PERCY: But I would like to know what else a sound finds in the ear besides hammers, anvils, and stirrups.