440 PSYCHOLOGY. 



" If we wish to begin to observe overtones, it is advisable, just 

 before the sound whieh is to be analyzed, to sound very softly the note 

 of which we are in search. . . . The piano and harmonium are well 

 fitted for this use, as both give overtones that are strong. Strike upon 

 the piano tirst the g' [of a certain musical example previously given in 

 the textj; then, when its vibrations have objectively ceased, strike 

 powerfully the note c, in whose sound g' is the third overtone, and keep 

 your attention steadily bent upon the pitch of the just heard g' ; you 

 will now hear this tone sounding in the midst of the c. ... If you 

 place the resonator which corresponds to a certain overtone, for ex- 

 ample g' of the sound c, against your ear, and then make the note c 

 «ound, you will hear g' much strengtliened by the resonator. . . . This 

 strengthening by the resonator can be used to make the naked ear 

 attentive to the sound whieh it is to catch. For when the resonator 

 is gradually removed, the g' grows weaker ; but the attention, once 

 directed to it, holds it now more easily fast, and the observer hears the 

 tone g' now in the natural unaltered sound of the note with his unaided 

 ear." * 



Wiiudt, coinmentiug ou experiences of this sort, says 

 that 



'' on carefully observing, one will always find that one tries first to 

 recall the image in memory of the tone to be heard, and that then one 

 hears it in the total sound. The same thing is to be noticed in weak or 

 fugitive visual impressions. Illuminate a drawing by electric sparks 

 separated by considerable intervals, and after the first, and often after 

 the second and third spark, hardly anything will be recognized. But 

 the confused image is held fast in memory ; each successive illumination 

 completes it ; and so at last we attain to a clearer perception. The 

 primary motive to this inward activity proceeds usually from the outer 

 impression itself. We hear a sound in which, from certain associations, 

 we suspect a certain overtone ; the next thing is to recall the overtone 

 in memory ; and finally we catch it in the sound we hear. Or perhaps 

 we see some mineral substance we have met before ; the impression 

 awakens the memory-image, which again more or less completely melts 

 with the impression itself. In this way every idea takes a certain time 

 to penetrate to the focus of consciousness. And during this time we 

 always find in our.selves the peculiar feeling of attention. . . . The 

 phenomena show that an adaptation of attention to the impression takes 

 place. The surprise which unexpected impressions give us is due essen- 

 tially to the fact that our attention, at the moment when the impression 

 occurs, is not accommodated for it. The accommodation itself is of the 

 double sort, relating as it does to the intensity as well as to the quality 

 of the stimulus. Different qualities of impression require disparate 



* Helmholtz: Tonempfindungen, 3d ed. 85-9 (Engl, tr., 2d ed. 50, 51 ; 

 see also pp. 60-1). 



