328 APPLIED PHYSIOLOGY 



Deafness due to a stoppage of the Eustachian tube is the most com- 

 mon form. It often can be relieved by opening the tube by swallow- 

 ing. By blowing the nose hard with the nose and mouth closed and at 

 the same time puffing out the cheeks and swallowing, one can almost 

 always force air through the tube into the ear and thus relieve the deaf- 

 ness. This should be done several times a day. 



Sometimes an inflammation extends from the pharynx up the Eusta- 

 chian tube and sets up an inflammation in the middle ear like that in 

 the throat. Mucus and matter then collect in the middle ear and 

 press upon the ear drum, causing a severe earache. If the tube does 

 not open, the membrane may burst and allow the matter to run out of 

 the ear. 



598. A running ear should be kept clean by cleansing it with warm 

 boiled water as often as the matter collects. Sometimes in running ears, 

 the disease eats away the bones and produces inflammation of the brain. 

 For this reason running ears are always dangerous. 



Some drugs may produce a ringing in the ears and partial deafness. 

 Quinine, which is taken for malaria, and salicylic acid, which is taken for 

 rheumatism, may cause it, but the effects pass off within a few hours. 



Boxing the ears suddenly compresses air against the drum mem- 

 brane, producing pain and sometimes even bursting the membrane. 

 Loud reports, as of cannon, cause such extensive and painful vibra- 

 tions of the membrane that deafness may result. 



599. Early in life a child may become deaf, and yet no 

 one may be aware of the trouble. Then the child is appar- 

 ently inattentive and does not answer when spoken to. 

 At school the teacher may ascribe his lack of attention to 

 carelessness or ill temper. In consequence, the child re- 

 ceives unjust punishment. The hearing of every dull and 

 inattentive child should be examined. 



600. The outer ear. Outside of the drum membrane 

 is a passage to the air about an inch in length and one 

 quarter of an inch in diameter, formed partly of bone and 

 partly of flesh. Around its opening is a shell-shaped fold 

 of flesh which, together with the passage, is called the 

 outer ear. Connected with it are rudimentary muscles 



