AND THEIE FUNCTIONS. 183 



Suidas, Tlieophrastus called it to ^loufxov, usually translated 

 the transolfacient. In a somewhat similar way, Aristotle 

 seems to have believed that air had a quality, to which 

 he gave no distinctive name, enabling the air to transmit 

 sound.* Theophrastus is said to have given to this quality 

 the name to ^inx^i, usually translated the trans-sonant. 



By reference to some of the main structures of the ear, 

 Aristotle gives a more practical explanation of the act of 

 hearing. He says, in effect, that the motion of sound is com- 

 municated through the air to the ear, the air acting like a 

 body which is ctw£%£j, or made up of matter without any 

 intervening spaces. The air then transmits its motion to 

 the air enclosed within the coiled passage of the inner ear 

 by the tympanum. t 



The ear is able to discriminate clearly different motions 

 transmitted through the air, Aristotle says, because the air 

 within it is normally at rest or nearly so.t In a similar 

 way, he believed that the other sense organs were normally 

 in what may be called a neutral or balanced condition 

 (^£(TOT)75), with respect to the influences by which they were 

 excited. § 



He does not say much about the anatomy of the ear. 

 After confuting a strange belief of Alcmeeon that goats 

 breathe through their ears, he says that the outer ear is 

 formed of flesh and cartilage, that the internal ear is of coiled 

 form, and that there is no duct from the ear to the brain, 

 but one to the chamber of the mouth. || This seems to show 

 that he was aware of the existence of what is now known as 

 the Eustachian canal, afterwards rediscovered by Eustachius 

 of Salerno (1500-74). 



He knew that dolphins, fishes, and many other aquatic 

 animals could hear, but says that they had no evident 

 organs of hearing.^ The existence of the internal ears of 

 these animals seems to have escaped his notice (although 

 he knew of the existence of otoliths in fishes), and nowhere 

 does he explain the manner in which they heard. 



Aristotle says that some people, dwelling near the sea, 

 asserted that fishes could hear better than other animals, 

 and that those fishes which could hear best were the grey 

 mullet, bass, and certain fishes called Chremps, Chromis, 



■■■■ De Anima, ii, c. 7, il'M. t Ibid. ii. c. 8, 4196 and 420a. 



I Ibid. ii. c. 8, 420a. § Ibid. ii. c. 11, 424a. 



il H. A. i. c. 9, s. 1. IT Ibid. iv. c. 8, ss. 5-9, ii. c. 9, s. 6, 



