46 



COLOUR VISION 



870 650 625 605 590 575 555 535 520 505 490 470 

 BCD E F 



450 



430 

 G 



Fig. 



10. Normal trichromat's luminosity curves lor different intensities of light {A, B, C, 

 cto. ; A being the lowest, and // the highest intensity). Abscissae, wave-lengths of 

 the prismatic spectrum of gas light ; ordinates, an arbitrary scale. (Konig.) 



6 8 10 12 H 16 18 Id ZZ Zt, U Z8 50 32 34 36 18 4o « 44 4€ 48 50 5Z 54 56 5B 60 62 64 66 

 m 3839« 506 S8-ISS'7 6l-3 



Fig. 11. Normal trichromat's photopic luminosity curves for the fovea, macular region, 

 and 10° from the fovea. Abscissae, arbitrary scale of the prismatic spectrum of the 

 arc light, the Fraunhofer lines and some important wave-lengths bemg indicated ; 

 ordinates, arbitrary scale, the maximum luminosity being 100. (Abney.) 



