30 UNIVERSITY OF MISSOURI STUDIES 



justing themselves to the permanent stretching and thus los- 

 ing their tension, as all living tissues do. We shall not, of 

 course, entertain for a moment this idea of the basilar mem- 

 brane being under constant tension, since our aim is not 

 unreality, but reality. We need not, therefore, discuss any 

 further the assumption of the presence of resonators in the 

 inner ear, which falls with the above rejected, preposterous 

 assumption of a permanent tension. That the membrane is 

 capable of resistance, as it probably is, means something 

 very different from the assertion that it is under constant 

 tension, which is biologically impossible. 



The actual question before us is evidently the question 

 as to the elasticity of the partition as a whole. Now, we 



have seen that the only element of it 

 Is the partition which, according to its structure, may be 

 as a whole regarded as elastic, is the basilar mem- 



elastic? brane. This membrane, however, we have 



found to be quite a small part of the bulk 

 of the partition. If the partition is displaced by an external 

 force and, this force having ceased, is caused to return to 

 its original place by the tension which the basilar membrane 

 has just suffered, such a spontaneous return movement must 

 be greatly retarded by the bulk of inelastic tissues of the 

 partition which the membranous part of it has to drag or 

 shove along with itself. A spontaneous return of the par- 

 tition to its normal position must be therefore very slow 

 when compared with the velocity of a displacement caused 

 by a rather powerful external influence from the stirrup. 

 Let us, then, keep in mind that with respect to the elastic 

 properties of the partition there are only two alternatives : 

 Either the basilar membrane is practically inelastic ; then 

 the partition as a whole is inelastic and cannot sponta- 

 neously return to its original position after having been 

 displaced. Or the basilar membrane is elastic : then the par- 



