74 THE WONDERFUL CENTURY. CUAP. ix. 



amount of this dust is well shown by the fact that, then 

 only, we can look full at the sun, even when the whole 

 sky is free from clouds and there is no apparent mist. 

 But the sun's rays then reach us after having passed, 

 first, through an enormous thickness of the higher strata 

 of the air, the minute dust of which reflects most of the 

 blue rays away from us, leaving the complementary yel- 

 low light to pass on. Then, the somewhat coarser dust 

 reflects the green rays, leaving a more orange colored 

 light to pass on; and finally some of the yellow is re- 

 flected, leaving almost pure red. But owing to the con- 

 stant presence of air currents, arranging both the dust 

 and vapor in strata of varying extent and density, and 

 of high or low clouds, which both absorb and reflect the 

 light in varying degrees, we see produced all those won- 

 drous combinations of tints and those gorgeous ever- 

 changing colors, which are a constant source of admira- 

 tion and delight to all who have the advantage of an 

 uninterrupted view to the west, and who are accustomed 

 to watch for these not unfrequent exhibitions of nature's 

 kaleidoscopic color-painting. With every change in the 

 altitude of the sun the display changes its character; and 

 most of all when it has sunk below the horizon, and, 

 owing to the more favorable angles, a larger quantity of 

 the colored light is reflected toward us. Especially 

 when there is a certain amount of cloud is this the case. 

 These, so long as the sun was above the horizon, inter- 

 cepted much of the light and color; but, when the great 

 luminary has passed away from our direct vision, his 

 light shines more directly on the under sides of all the 

 clouds and air strata of different densities; a new and 

 more brilliant light flushes the western sky, and a dis- 



