302 AVERS. [Vol. VI . 



possible variation in wave length of sonorous vibrations, any 

 more than we receive a distinct series of specific visual im- 

 pulses for every possible wave length of luminous vibrations. 

 In each case we probably have a number of primary sensations 

 from the various mingling of which, in different proportions, 

 our varied complex sensations arise ; the difference between 

 the eye and the ear being that whereas in the former the num- 

 ber of the primary sensations appears to be limited to three or 

 at least six, in the latter, thanks to the organ of Corti, the 

 number is very large : what the exact number is we cannot at 

 present tell." There could be no genuine analysis unless the 

 ear did in some way respond to each vibration in wave length, 

 and from the anatomy of the cochlear sense organs this is very 

 probably the case. The manner in which this is carried out 

 has already been indicated. 



There is, however, on further consideration, another set of 

 conditions which probably affect the appreciation of sound ; viz. 

 the state of the sensorium into which the sound waves enter. 

 This state is determined by previous and present sensations 

 not from the ear alone, but from other sense organs as well, and 

 is sufficient to determine the ultimate sensation due to a given 

 stimulation by sound waves. This is, however, a subject of 

 great obscurity and difficulty, but it should not be left uncon- 

 sidered in any discussion of the qualities and conditions of 

 psychical audition. These phenomena belong to the still un- 

 known borderland between the external tone-generating physi- 

 cal universe and the internal psycho-physiological tone-perceiving 

 apparatus, — the auditory hair and ganglion cells of the audi- 

 tory centres with their numerous connections with other appa- 

 ratuses of the brain. There is a gradation of phonomena from 

 the purely physical and external to the purely subjective or 

 internal auditory sensations. The latter are not primarily' 

 dependent upon the former, and include phenomena of subjec- 

 tive music by mental effort and all involuntary subjective tone 

 perceptions. As an example of the latter class of phenomena 

 I give the following personal experience. I had been riding all 

 night on the cars and was engaged in reading the morning 

 paper, and as I sat but a few seats from the car door and facing 

 it, I could hear distinctly the slamming of the door as trainmen 

 passed in and out. As I had lost the night's rest, the quiet 



