THE SPECIAL SENSES. 143 



Unlike the eyes, each ear is independent of the other, and 

 can receive different impressions at the same time. 



In some of the lower animals the outer ear is movable. 

 This enables them to turn it in the direction of the sound, 

 a valuable means of protection to wild animals who prey 

 upon each other. 



22. Hygiene Of the Ear. The essential part of the ear 

 being deeply seated and away from outward influence, this 

 organ is not subject to injuries and derangements to the same 

 extent as the eyes. Still, the ear may become affected, and 

 the hearing impaired, or even destroyed. Deafness in one 

 ear is by no means uncommon. Temporary deafness may 

 result from the closing of the canal by a collection of wax. 

 In attempting to remove this with a pin or a hard-pointed 

 substance of any kind, there is danger of injury to the 

 drum. The safest way is to drop in a few drops of warm 

 sweet oil, and afterwards gently syringe out with warm water. 

 An insect sometimes gets into the canal, causing a good deal 

 of pain. It can generally be drowned with warm water, or 

 killed with a few drops of oil, and then washed out. Cold 

 water should not be allowed to run into the ear, and a cold 

 wind blowing against the ear may affect the sensitive nerve, 

 causing "ear-ache." A closing up of the tube leading into 

 the throat, from a cold or other inflamed condition of the 

 throat, may produce temporary deafness. 



23. The Sense Of Touch. The sense of touch is 

 distributed all over the body. The skin everywhere is 

 endowed with sensibility. But in certain parts, as the tip 

 of the tongue and fingers, the sense of feeling or touch is 

 developed to a high degree. Touch is, to a large extent, an 

 educated sense. It begins to develop in infancy. There is 

 no special nerve of touch, but in the fingers the little papillae 

 mentioned in connection with the skin have each a special 

 nerve ending, a sort of touch corpuscle. 



