MECHANICS OF THE INNER EAR 



77 



certainty, the third produces the tone 4, the fourth the tone 

 2, and the fifth the tone 1. 



The fluid quantity for the tone 9 is measured, as we found 

 above, by the relative number nine. Now, let us, for exam- 

 ple, assume that this means an equal number of fluid 

 units in our table. We then read off the corresponding par- 

 tition length as being 24.11 units. The fluid quantity for the 

 uncertain tone was measured as two units. But now, we can- 

 not simply read off from the table the number of partition 

 units corresponding to two; for the partition section making 



TONE INTENSITIES IN THE COMBINATION 4 AND 9 



room for these two fluid units is not an initial section. We 

 must read off, therefore, the value corresponding to eleven 

 fluid units (26.42) and subtract from this the value correspond- 

 ing to nine fluid units (24.11). We thus see that the length 

 of the partition section about the tone of which we could not 

 come to a decision is 2.31 units. The fluid quantity for the 

 tone 4 was measured as twenty-two. But here again we can- 

 not simply read off the length of the partition section pro- 

 ducing this tone, because this section is not an initial section. 

 We must read off the values for 9-+ 2+22=3 3 and for 9+2=11 

 and subtract the latter from the former. These values are 

 42.28 and 26.42. The length of that section of the partition 



