THE BOORS. 161 



the tympanum, they will produce inflamma- 

 tion ; and in the end, perhaps, cause deafness 

 or death. 



I wish I had room to tell you more about 

 this cavity of the ear, and indeed about the 

 whole organ of hearing ; for it is a curious 

 organ. But all I can say now, is a few words 

 about the labyrinth. 



This is a large cavity still deeper in the 

 head than the foregoing, and, if possible, still 

 morevcurious in its structure. 



The middle part of the cavity is called the 

 vestibule. It is somewhat oval in shape. At 

 one end of it are three tubes, each of which is 

 so bent or curved as to form almost a circle. 

 They open into the vestibule, and are called 

 semi-circular canals. 



At the other end of the vestibule is a tube 

 of a conical shape, but resembling, on its out- 

 side, the shell of a snail. It is called the 

 cochlea. This also opens into the vestibule. 



The little bones of the ear are connected 



with the ear drum on one side, and with the 



parts of the labyrinth just described on the 



other. The labyrinth, in all its parts, is most 



14* 



