734 



LIGHT ABSORPTION BY PIGMENTS IN VIVO 



CHAP. 22 



a yellowish-green tinge, as compared with the bluish-green color of water 

 as such. Figure 22.55 shows the spectral composition of light in different 

 depths of the Mediterranean on a clear day according to Seybold (1934). 



100 



360 



680 720 



440 520 600 

 WAVE LENGTH, m^ 



Fig. 22.54. Absorption curve of pure 

 water (a = specific absorption coefficient). 

 S, Sawyer (1931). A, Aschkinass (1895). 



400 500 600 700 



WAVE LENGTH, m/i 



Fig. 22.55. Energy distribution under 

 1-50 m. water (after Seybold 1934). 



Table 22.X 



Spectral Composition of Light under Water" 

 Italics indicate position of maximum of transmission. 



A. transmission by a five meter thick layer* 



IXlfl 



Water 



700 



650 



600 



550 



500 



450 



400 



B. SPECTRAL COMPOSITION OF LIGHT IN DIFFERENT DEPTHS'' 



Depth 



Per cent 



350 



Red 



Orange 



Yellow 



Green 



Blue 



Violet 



" For more information, see e. g., Schmidt (1908), Knudsen (1922), Hulburt (1928), 

 Atkins (1932) and the book by Dorsey (1940). * Shelford (1929). ' Trout Lake, Wis- 

 consin, according to Manning, Juday and Wolf (1938). 



