MECHANICS OF THE INNER EAR 93 



Let us return to the theoretical analysis of the whole 



curve in figure 26. From A to C the stirrup moves inwards, 



pushing down a certain length of the parti- 



„, . tion. The initial part of this length, how- 



The successive r 



positions of the ever, begins a slow upward movement as 

 partition corres- soon as the velocity of the stirrup begins 

 ponding to to decrease, at B. The same part moves 



figure 26 up more quickly when, at C, the stirrup 



reverses its movement and begins to pull 

 it upward. We therefore see at B in figure 29- the initial two 

 sections in an extreme downward position. At C, we see them 



A i. ■ — 



B { y >--- 



C ^ -- 



PL U , — 



£t j - , — 



n 1 - - 



c .... 



Fig. 29. The combination 1 and 2. Compare figure 26 



only in a medium downward position, and at the same time 

 we find the following two sections of the partition in a similar 

 downward position since the stirrup has continued, from B to 

 C, to move inwards. It is plain that to take into account, in 

 our graphic representation, only two kinds of displacements in 

 either direction, an extreme and a medium one, is again an ar- 

 tificial simplification, introduced merely to suit our momentary 

 needs, in spite of the fact that thus we lose sight of some of the 

 details of the movement. Actually, the movement probably 

 occurs rather in the form of figure 28. But the simplification 

 used in figure 29 not only renders the drawing of the figure 



