No. I.] THE VERTEBRATE EAR. 293 



" analysis " in connection with it is not only useless but mislead- 

 ing, since there can be no analysis of the discrete waves when 

 each produces its own effect, no matter what has gone before or 

 is to succeed it. That this term " compound wave " is generally 

 understood in a different sense, the following quotation from 

 Foster clearly proves. 



Foster (1891, 92) says on this subject {loc. cit. p. 1211): 

 " The vibrations of a musical sound as they pass through the 

 air or other medium are not discrete ; the vibrations corre- 

 sponding to the fundamental tone and overtones do not travel 

 as so many separate waves ; they all together form one complex 

 disturbance of the medium ; and it is as one composite wave 

 that sound falls on the membrana tympani, and passing through 

 the auditory meatus, breaks on the terminations of the auditory 

 nerve. And when two or more musical sounds are heard at the 

 same time, the same fusion of the waves occurs. Since we can 

 distinguish several tones reaching our ear at the same time, it 

 is clear that we must possess in oily minds or in our ears [italics 

 mine] some means of analyzing these composite waves of sound 

 which fall on our acoustic organs, and of sorting out their con- 

 stituent vibrations." Our author, then, continues with an ex- 

 planation of how the strings of a piano analyze the compound 

 note of the human voice into its component simple tones, say- 

 ing, "The note sung reaches the strings as a complex wave 

 [italics mine], but these strings are able to analyze the wave 

 into its constituent vibrations, each string taking up those vibra- 

 tions, and those vibrations only, which belong to the tone given 

 forth by itself when struck." The following opinion is equally 

 decisive of the sense of the term analysis as used by physiolo- 

 gists : " The cochlea of the ear resembles a series of differen- 

 tially toned resonators, an analyzing apparatus which works in 

 strict accordance with Fourier's law, and practically solves the 

 problem in this simple manner. The organ of 440 vibrations 

 selects the fundamental tone, that of 440 x 2 the first harmonic, 

 that of 440 X 3 the second, and so on. Further, each sympa- 

 thetic apparatus vibrates with an intensity corresponding with 

 the intensity of the harmonics of the note produced ; and in this 

 manner the whole note is analyzed into a number of simple 

 tones, in a manner as perfect as any we can conceive. 



"After this process of analysis, however, there follows a 



