46 



COLOUR VISION 



3-8- 



36- 



34- 



3-2 



3-0 



2-8- 



2-6- 



2-4- 



2-2 



2-0 



1-8 



1-6 



1-4 



1-2 



1-0 



08 



0-0 



0-4 



0-2 



.Light intensities H 



': S. 

 \ V 





G 

 F 

 E 

 D 

 C 

 B 

 A 



870650625605590575 555 535 520 505 490 

 BCD E F 



470 



450 



430 

 G 



Fig 



10. Normal fcrichromat's luminosity curves for different intensities of light (A, B, C, 

 etc. ; 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 



14 16 18 20 ZZ 

 2M 



26 28 30 32 34 36 IS 40 



38.J9-8 



44 4 48 SO II 54 56 58 60 62 64 66 



506 59- 1 59 -761-3 



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 Fraunhot'er lines and some important wave-lengths being indicated ; 

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



