Du We Hear Sound? 5 



subjective physiological fact that the ear i>icks up a 

 droi)ped vibration in high frequencies up to 1 /250th of a 

 second. This eliminates any feature which includes the 

 element of inertia. The phonograph and ear mechanism 

 therefore become very dissimilar. K we are to agree 

 that an ear cannot operate under the requirements of 

 an indirect activation it is not unlikely that all theories 

 based on this premise are also erroneous. This not only 

 accounts for the variations in interpretation of the end- 

 organ function but it also makes their discussion unnec- 

 essarJ^ 



The assumption that we do hear sound is much more 

 satisfactory from a biological view point. It falls in 

 line with the activating factors which operate other 

 sense organs. One does not assume that the retinal cells 

 are indirectly activated by a radiant heat reflected from 

 the choroid merely because the choroid is black. One 

 does not construct thermo-sensitive organs out of rods 

 and cones to explain why they face what a])pears to be 

 the wrong way and why they touch the pigment layer. 

 One regards the eye-ball as a reasonably light-proof 

 space exce})t to the energies entering the pupil. One 

 searches, as Parker has done, for an explanation of the 

 inverted retina and finds it in the comparative anatomy. 

 We may therefore assume that the inner ear occupies a 

 reasonably sound-proof si)ace except for the energies nor- 

 mally entering through the footplate. We may also 

 search for the explanation of the refined histology of the 

 end-organ in the pattern u])on which it is developed 

 rather than in terms of functional requirements. 



Over a hundred years ago before the histology of the 

 end-organ had been reported by Corti, men thought seri- 

 ously on this problem. Carlisle in 1805 made far reach- 

 ing deductions on the basis of comparative aiuitomy. 

 Later in the forties the great anatomist and ])hysiologist 

 Johannes Mueller }»erformed experiments which formu- 



