THE SENSES 149 



Mke a sounding box to make it plainer and more distinct. 

 The inner ear is the real ear. Some animals, like fish, 

 have only an inner ear. 



297. The Eustachian tube. The middle ear is filled 

 with air. From it a tube, called the Eustachian tube, ex- 

 tends to the back part of the nose. When you blow your 

 nose hard, you can force air up the tube. This makes 

 your ears feel full, and you become partly deaf. When 

 you have a cold, the tube may become stopped, and then 

 your ear rings and feels as if you had blown air up the 

 tube. If it stays stopped, you may become deaf. 



Sometimes a cold in the throat extends up the tube and 

 into the middle ear. Then you have an earache, and per- 

 haps your ear may discharge matter like that from your 

 throat. Throat trouble is the most common cause of ear- 

 ache and deafness in children. If a child breathes through 

 his mouth or has too large tonsils or anything growing 

 in the back part of his nose, he is very liable to have ear- 

 ache or deafness. So it is very important for you to have 

 your nose and throat in good order if you would have good 

 hearing. Scarlet fever often causes deafness, because the 

 inflammation of the throat extends up the tube to the ears. 



298. Dull children. Sometimes children get throat 

 trouble and earache before they can talk. Then they 

 grow up slightly deaf, but neither they, nor their parents, 

 nor their teachers know it. Such children cannot hear 

 well when spoken to, and so seem to be dull and careless. 

 Often they are punished for not attending to their work. 

 This is very unjust to the child. Every child that seems 

 inattentive or slow in obeying should have his hearing 

 tested. Hold a watch to his ear and see if he can hear 

 it as far away as you can. 



299. Care of the ears. Boxing the ears may burst the 



