504 PSYCHOLOGY. 



sense-impression. The image seems to welcome its own 

 mate from out of tiie compound, and to heighten the feel- 

 ing thereof ; whereas it dampens and o})poses the feeling of 

 the other constituents ; and thus the compound becomes 

 broken for our consciousness into parts. 



All the facts cited in Chapter XI, to prove that attention 

 involves inward reproduction, go to prove this point as 

 well. In looking for any object in a room, for a book in a 

 library, for example, we detect it the more readily if, in 

 addition to merely knowing its name, etc., we carry in our 

 mind a distinc^. image of its appearance. The assafoetida 

 in ' Worcester,:'hire sauce ' is not obvious to anyone who 

 has not tasted assafoetida per sc. In a ' cold ' color an 

 artist would never be able to analyze out the pervasive 

 presence of blue, unless he had previously made acquaint- 

 ance with the color blue by itself. All the colors we ac- 

 tually experience are mixtures. Even the purest primaries 

 alwaj'S come to us with some Avhite. Absolutely pure red 

 or green or violet is never experienced, and so can never 

 be discerned in the so-called primaries with which we have 

 to deal : the latter consequently jiass for pure. — The reader 

 will remember how an overtone can only be attended to in 

 the midst of its consorts in the voice of a musical instru- 

 ment, by Lounding it previously alone. The imagination, 

 being then full of it, hears the like of it in the compound 

 tone. Helmholtz, whose account of this observation we 

 formerly quoted, goes on to explain the difficulty of the 

 case in a way which beautifully corroborates the point I 

 now seek to prove. He says : 



" The ultimate simple elements of the sensation of tone, simple tones 

 themselves, are rarely heard alone. Even those instruments by which 

 they can he produced (as tuning-forks before resonance-chambers), 

 when strongly excited, give rise to weak harmonic upper part ials, partly 

 within and partly without the ear. . . . Hence the opportunities are 

 very scanty for impressing on our memory an exact and sure image of 

 these simple elementary tones. But if the constituents are only indefi- 

 nitely and vaguely known, the analysis of their sura into thera must 

 be correspondingly uncertain. If we do not know with certainty how 

 much of the musical tone under consideration is to be attributed to its 

 prime, we cannot but be uncertain as to what belongs to the partials. 

 Consequently we must begin by making the individual elements which 



