368 PROCEEDINGS OP THE AMERICAN ACADEMY. 



of color can be used in connection with the one described, in the manner 

 shown in the following diagram : — 



As we increase the number and variety of tones to be kept all at 

 equal intervals of equal contrasts, all in perfect rhythm and balance, 

 the problem of consistency, which is the problem of art, becomes more 

 and more difficult. 



There is a possible objection to the system of color-values or tones 

 which I have described. In the spectrum the colors are all equally 

 intense. They differ only in value or luminosity. In the system just 

 described this equality of intensity is ignored, and as to the luminosities, 

 if they are observed on the hot side of the spectrum, they are ignored on 

 the cold side, and if they are observed on the cold side they are ignored 

 on the hot side. A different arrangement of values and colors is pos- 

 sible. If we distribute our range of light into five registers, — a register 

 of half-tones, a register of lights, a register of darks, a register of high 

 lights, and a register of extreme darks, — we can consider each one of 

 these five registers as a potential spectrum, and we can arrange the colors 

 in each register according to their several values or luminosities and have 

 them all equally intense. The increase or diminution of intensities is 

 not, then, from color to color but from register to register. In the scale 

 of five registers, the middle one will be the register of greatest intensities. 

 Tiie registers above it and below it will be registers of less and of least 

 intensity. This system is described in the following diagram : — 



