136 PHYSIOLOGY FOR XTKSKS 



over to conveying sound waves. A part of this nerve 

 is distributed to the semicircular canals and, apparently, 

 conducts sensation to that part of the cerebellum which 

 aids in maintaining equilibrium. They are not the only 

 nerve fibers which convey impulses necessary for this 

 function, but are important paths for such stimuli. 

 The auditory canal, which is nearly an inch in length, 



Fig. 33. Semidiagrammatic section through the right ear (Czermak); G, 

 external auditory meatus; T, membrana tympani; P, tympanic cavity or 

 middle ear with the auditory ossicles stretching across it and the Kustachian 

 tube (J3) entering it; o, oval window; r, round window; B, semicircular 

 canals; 5", cochlea; Vt, upper canal of cochlea; Pt, lower canal of cochlea. 

 (From llowell's Physiology.) 



is the site of the accumulation of that mixture of the 

 secretion of the sebaceous glands with worn-out cells 

 which we call "ear wax." It is often present in amounts 

 sufficient to impair acuteness of hearing and must IK- 

 softened and removed, a duty frequently falling upon 

 the nurse. 



That our sense of the location and distance from which 

 sounds come is not very acute, is a matter of common 



