Chap. V 1 



THE EAR. 



having the same direction as the petrous bone. The 

 external meatus, the promontory, the cochlea, and the 

 internal meatus lie nearly in the same line. The 

 canal has a vertical curve about its middle, with the 



Fi<*. 12. Section through the external Meatus, Middle Ear, and 

 Eustachiau Tube (Tillanx). 



, External auditory mentiis ; 6, tympanum ; e, EiiBtaeliian tnho ; d, internal 

 auditory mcatus ; e, cochlea ;/, Mticlea ; <j, lucinbrana tympani; ft, -ijl.ihl 

 process. 



convexity upwards. To straighten the canal for the 

 introduction of specula and other instruments, the 

 pinna should be drawn upwards and a little outwards 

 and backwards. The osseous part, forms a little more 

 than one-half of the txibe, and is narrower than the 

 cartilaginous part. 



Jn the infant at one year, a third only of the 



