54 UNIVERSITY OF MISSOURI STUDIES 



have just seen, deviate from the average, particularly in the 

 middle of the period. Now, some one might prefer to 

 conclude that we ought not to hear the tone 25 all the 

 time, but at first a tone somewhat lower than this, gradually 

 rising slightly and falling again in pitch towards the end of the 

 period. Whether we should draw this conclusion I will not 

 attempt to decide. Neither do I care to express a definite 

 opinion as to what we actually hear. Let the reader who 

 wants to know this find it out by an experiment of his own. 

 What I must point out, however, is the fact that the time inter- 

 val between two maxima is not necessarily the time between 

 two stimulations. In a provisional way, the interval be- 

 tween two maxima or between two minima or between two 

 points of inflection or between two points of any other name 

 and definition may be used thus, but let us always remember 

 that this is only a provisional, an artificially simplified method, 

 which can scarcely yield more than a rough approximation of 

 what actually happens. 



Another section of the partition moves up and down twen- 

 ty-four times during the period. The length of this section, 

 which determines the relative intensity of 

 Do we hear the tone heard, is derived from the table 



the tone 24? as being twenty-one (221 — 200). If we 



look at the time interval between the 

 successive maxima, we find this to be at the beginning of 

 the period • one hundred and forty-seven, to decrease gradually 

 to one hundred and forty-five at the maximum twenty-three, 

 to be two hundred and thirty from maximum twenty-three to 

 maximum twenty-seven (maximum twenty-five lias disappeared, 

 as seen in figure 21), and to fall again to one hundred and 

 forty-five. Here again, I will not attempt to decide what we 

 ought to expect theoretically, because we have no right to 

 deduce anything definite from a theory in a direction in which 

 this theory is as yet professedly indefinite, in which it obvious- 



