CHAP, iv.] HEARING. 1019 



( 628), that waves of sound falling on the auditory fibres 

 themselves may give rise to auditory sensations, we arrive at 

 the conception that the auditory impulses are mere copies so 

 to speak of the physical sound waves, a conception which, if 

 substantiated, would necessitate a revisal of all our views con- 

 cerning nervous impulses. 



