86 



THE DESEKT 



Sand- 

 storms. 



Reflections 

 upon sky. 



in the dramatic sand-storm a veritable sand- 

 fog which often turns half the heavens into a 

 luminous red, and makes the sun look like a 

 round ball of fire. 



The dust-particle in itself is sufficient to ac- 

 count for the warmth of coloring in the desert 

 air sufficient in itself to produce the pink, yel- 

 low, and lilac hazes. And yet I am tempted to 

 suggest some other causes. It is not easy to 

 prove that a reflection may be thrown upward 

 upon the air by the yellow face of the desert 

 beneath it a reflection similar to that produced 

 by a fire upon a night sky yet I believe there 

 is something of the desert's air-coloring derived 

 from that source. Nor is it easy to prove that 

 a reflection is cast by blue, pink, and yellow 

 skies, upon the lower air-strata, yet certain 

 effects shown in the mirage (the water illu- 

 sion, for instance, which seems only the reflec- 

 tion of the sky from heated air) seem to suggest 

 it. And if we put together other casual obser- 

 vations they will make argument toward the 

 same goal. For instance, the common blue 

 haze that we may see any day in the moun- 

 tains, is always deepest in the early morning 

 when the blue sky over it is deepest. At noon 

 when the sky turns gray -blue the haze turns 



