122 



THE DESEET 



Horses and 

 cattle in 

 mirage. 



Illusion of 



rising 



buttgs. 



high up in the air with the legs of the horses 

 twenty feet long and the wagon as large as a 

 cabin. The stilted antelope "forty feet high 

 and npside down" is as seldom seen in the 

 sky as upon the earth ; bnt desert cattle in 

 bunches of half a dozen will sometimes walk 

 about on the aerial ceiling in a very astonishing 

 way. 



Yet these, too, are infrequent appearances. 

 Nor is the illusion of buttes rising from the 

 plain in front of you often seen. It happens 

 only when there are buttes at one side or the 

 other, and, I presume, this mirage is caused by 

 the bending of the light-rays to the right or left. 

 It presents certainly a very beautiful effect. 

 The buttes rise up from the ground, first one 

 and then another, until there is a range of them 

 that holds the appearance of reality perhaps for 

 hours, and then gradually fades out like a stere- 

 opticon picture — the bases going first and the 

 tops gradually melting into the sky. When 

 seen at sunset against a yellow sky the effect is 

 magnificent. The buttes, even in illusion, take 

 on a wonderful blue hue (the complementary 

 color of yellow), and they seem to drift upon the 

 sky as upon an open sea. 



The bending of the light-rays to either side 



