282 The Evolution of Optics 



54 Red. 



140 Orange-red. 



80 Orange. 



114 Orange-yellow. 



54 Yellow. 



206 Greenish-yellow. 



121 Yellowish-green. 



134 Green and Blue-green. 



32 Cyan-blue. 



40 Cyan. 



20 Ultramarine and blue- violet. 



5 Violet. 



1,000 

 Condensing the intermediates with the principals, we have : 



Bed colors 194 



Golden colors 454 



Green colors .255 



Blue colors 97 



1,000 " 



The explanation of such a grouping of light- waves is taken 

 to be due to the fact that, among the color stimuli which 

 the eye has received, the golden stimuli have largely predomi- 

 nated. The ordinary diffused daylight is slightly yellowish, 

 and obscuration, as from a turbid atmosphere, increases this 

 hue. The rising and the setting sun floods the earth with 

 golden light ; again, the yellow light of fire has, since the 

 first dawn of civilization, played a most important place in 

 man's history. By fire-worship, by burnt-offerings in almost 

 any form of religious belief, the golden firelight has im- 

 pressed itself on man's attention. 



The next most important class is that of the greens 

 which are abundantly present in nature, being the pre- 

 dominant color in vegetation. 



The next class is that of the reds, where we meet with a 

 very interesting and important fact. Were any of us asked, 

 "Which is the strongest color?" I think we would reply, 

 " Red," unless we had looked into the matter a little critical- 

 ly, and we would be surprised to find that red is not a color 

 of high luminous power, nor can the feeling of the striking 

 and important nature of red be due to the fact that the 

 quantity of the red stimulus in nature has been powerful 

 enough to give it this exalted place in our estimation. 



The explanation of this fact Dr. Gould finds to be 



