Questions.—How is sound made? How does it get to our ears? Tell about the vibration of sound in a log. What is said about the dying away of sound? What is this like? What is an echo? What is said about speaking in a building? What about speaking through a tube? Tell how we hear sound. Tell about the little bones in the ear. What do these bones do? Tell what the different vibrations are in hearing. What is said about the puffing of a locomotive? Why do some animals have large ears? Why are our ears so small? What animals can turn their ears different ways, and why? How is the inner part of the ear guarded? Tell what is said about the wax.
CHAPTER XIV.
THE SMELL, THE TASTE, AND THE TOUCH.
I have told you that most of what the mind knows about the world around it comes to it by the sight and the hearing. But it learns a great deal by the other senses, and these I will tell you about in this chapter.
How we smell things.
Did you ever think how it is that you smell any thing? You put a rose up to your nose, and the fragrance is pleasant to you. Now what is this fragrance? Is it something that goes up into your nose? You can not see any thing come from the rose. But in reality very fine particles come from it. They are finer than the finest powder. They float every where about in the air, and, as you breathe, they go with the air into your nostrils. Every perfume that you smell is made of such particles.
But how do you think the mind knows any thing about these particles when they come into the nose? It is in this way. In the lining of the nose are the fine ends of the nerve of smell. These ends of the branches of this nerve are so small that you can not see them. Now the fine particles that I have told you about touch these ends of the nerve, and the nerve tells the mind about them; and this is smelling.
The nose is a more extensive organ than most people think it is. There are divisions in it. These fold on each other in such a way that there is a great deal of surface in the nose, and the ends of the nerve of smell are all on this surface.
The smell of some animals.