94 UNIVERSITY OF MISSOURI STUDIES 



easier, but also contributes towards a readier comprehension 

 of the significance of the graphic representation, towards a 

 quicker reading off of the tones to be heard. 



At D we see the first section in an extreme upward position 

 since the stirrup has moved outwards and has reached a max- 

 imum velocity. At E, the first section has returned to a me- 

 dium displacement since the velocity of the stirrup has reached 

 a minimum. At the same time the second section of the par- 

 tition has moved upwards as a result of the continued outward 

 movement of the stirrup. At F we find the initial three sec- 

 tions of the partition in an extreme upward position ; for the 

 stirrup has continued to move outwards and has also reached 

 a maximum of velocity. At G all four initial sections of the 

 partition are in an upward position since the stirrup has con- 

 tinued to move outwards. But they are only in a medium 

 displacement since the velocity of the stirrup has again reach- 

 ed a minimum. 



Looking now over the four columns in figure 29, we notice 

 that the first shows an extreme upward position of this section 

 of the partition at F, a medium upward 

 De we hear position at G=A, an extreme downward 



both tones position at B, a medium downward posi- 



2 and 1? tion at C, an extreme upward position at 



D, a medium upward position at E, an ex- 

 treme upward position again at F. This section of the parti- 

 tion, therefore, has moved up and down twice during the pe- 

 riod, the second upward movement occurring between E and 

 F. It is quite probable, then, that the nerve ends located on 

 this section receive two shocks during the period. The second 

 section of the partition has an extreme upward position at F, 

 a medium upward position at G=A, an extreme downward 

 position at B, a medium downward position at C and D, 

 and a medium upward position at E. It follows that 

 this section moves up and down only once during the pe- 



