464 



movement of the pointer), as well as the time during which the current remains 

 closed. The moment when the circuit is made is the moment when the observer 

 imitates the tap, i. e. when he announces the moment at which he apprehends 

 the sound stimulus; the time of the electric current represents the duration of 

 auditory sensation. It is obvious that we can hardly expect absolute precision in 

 this report, but important conclusions may be drawn from it with certainty, as 

 already appears from the subjoined short portions of some curves. 



The middle curve shows the reproduction of the auditory sensation of the 

 observer, the upper one is an illustration of the stimulus itself. This stimulus 

 consisted of a series of ticks given by an electrical hammer. The moment the 

 regularly moving hammer touches the layer, thereby eliciting the sound-stimulus 

 can readily be registered electrically in the same way as the taps given by the 

 observer. The bottom curve shows the time in '/^j seconds: 



Fig. 1. 



I. Falling 2-rhythm — — 



II. Rising 2-rhythm ~- — 



III. Falling S-rhythm —• 



IV. Amhybrachic 3-rhythm s_^ — ^ 



We have measured the intervals of time between the records of the moments 

 at which the observer announces the perception of the auditory stimulus. 



The results of the measurements are given in the annexed 

 tables : 



