1.If you look into the ear of the boy sitting next you，you will see a little tunnel leading right into the head.This tunnel leads to the most important parts of the ear，which are lodged within a mass of hard bone for protection.What we commonly call the ear is only the external ear.It is a trumpet for collecting the quicktremorsof the air，which we call “sound-waves，”and fordirecting them into the tunnel we have just mentioned.
2.This external eat is not necessary to hearing，and those who have had their ears cut off-a punishment sometimes inflicted by the Red Indians upon their enemies-can hear fairly well，though not quite so plainly as before.To many animals the outer ear is of greater service than it is to man：the horse，by turning its ears about，finds out in what direction a sound is loudest，and thus knows whence it proceeds.Notice how a horse will turn its ears towards you，if you make a noise to attract its attention.
3.Savage men also have the power of finding out the direction of sounds by moving their ears；and travellersin Australia relate how the Bushmen，squattingbynight round the camp fire，constantly turn their eyes and ears about，suspicious of every sight and sound.We have no need of being so continually on the alert，for we are not always going about in terror of our lives；and after many generations of disuse，the muscles have lost their power of movement.Most of us，however，have tiny ear muscles still left，and one or two in the class will probably be able to use them so as to cause a very slight movement of the ears.
4.You will hardly believe that，owing to the want of this power，you cannot tell，without the help of your eyes，whether a sound comes from behind or from the front.Bandage your eyes，and ask two friends to stand one in front of you and the other behind.Let one of them click two pennies together，and you will not be able to say which friend made the click.You will generally think that the sound comes from behind；for we are so accustomed to see any sounding body which is situated in front of us，that when our eyes are bandaged and we do not see it，we are deceived into thinking that it must be behind us.
5.If an insect should crawl into the tunnel of your ear，it would not be able to go very far.At a distanceof less than an inch，it would be stopped by a thin partition，called the drum of the ear.Beyond this partition there is a chamber called the middle ear ，and this communicates with the back of the throat by a long passage.
6.The middle ear contains a chain of three little bones，called，from their curious shapes，the hammer ，the anvil ，and the stirrup ；and these attach the ear drum to another drum，which closes the entrance to a third chamber，called the inner ear .This inner ear isfilled with a watery fluid.When sound-waves cause thedrum of the ear to vibrate，the motion is transmittedby the chain of bones to the inner ear，and the fluid within it vibrates in the same way.
7.This inner ear consists of some very long winding pa ssa ges in thebone of the head.Henceit is termed the labyrinth .Floating in the fluid which itcontains，we find a membrane ，called the basilar membrane，which is composed of thousands of tiny microscopic threads；and from these，thousands of nerve fibres，like white threads，pass to the brain.
8.In order to understand how it is that the brain is affected by the sound-waves，you would require to open the top of a piano and watch the piano wires.When you sing a note，one or two wires will be set in motion by the sound-waves of your voice.Stop singing and listen，and you will find that these wires have taken up the note you sang，and by their vibrations are producing a faint sound of the same pitch.If you tie a thread to one of these wires，it too will be set in motion.Thisis practicallya model of what takes place in the ear；for the tiny threads of the basilar membrane move to and fro，just like the piano wires when a sound is made.These affect the nerves，just as the piano wire affects the thread tied to it.
9.The ear is a very wonderful and complicated organ，and the work it has to do is very varied.By its help we become conscious of all the hundred sounds of the city or the country-side，from the deepest to the shrillest；and if we listen carefully to a tolling bell，we hear in every note the several blended tones that it rings forth.
Of even greater importance is the power which hearinggives to us of understanding our fellow-creatures’thoughts and wants，of listening to the voice of friend or teacher，and of developing our minds and characters by what we learn from them.
