THE GREAT MIRROR 



70 



again, at different intensities, into pronounced 

 tones. Thus on warm summer days, in tropical 

 regions, the air over the sea at sunrise will 

 be pale blue; at noon, if the heat continues, it 

 will show a trembling dancing gas-blue; and 

 by three of the afternoon perhaps it is rosy 

 blue or opalescent — something that shimmers 

 and changes like mother-of-pearl. 



Given such an atmosphere above a smooth 

 water surface and the inevitable result is that 

 supreme beauty of reflection — the opal sea. 

 The sea not only reflects the air, but its very 

 surface seems to be changed by it into an opal- 

 escent transparency; just as the sky overhead 

 is modified by it into something that looks like 

 blue seen through opalescent glasses. Other 

 atmospheres, more or less color-laden, that lie 

 above the sea are as clearly reflected but per- 

 haps not as readily noticed. The silver gray 

 that comes with mist or fog is so common that 

 we hardly see its effect at all; and the deep 

 purple that comes with twilight — so deep that 

 you can see it, looking out the darkening cir- 

 cle of the ship's cabin windows, as a block of 

 indigo — is again overlooked because of its fre- 

 quency. But the gas-blue which comes with 

 great heat puts a very remarkable face upon 

 the sea, and the opalescence is so splendidly 



Color in 

 the tropica. 



The opal 

 sea. 



Silver grays 

 and twi- 

 light pur- 

 ples. 



