60 



NATURE FOR ITS OWN SAKE 



Trans- 

 mitted 

 light. 



Sky lights 

 n the earth. 



which may, perhaps, be cleared up by some such 

 explanation as this : Glancing up at the sky our 

 eyes look inevitably into the shadows of air par- 

 ticles ; the light that comes to us is transmitted 

 through and between the particles. Glancing 

 down at the paper, we are looking into the high 

 lights of the paper instead of shadows; the 

 light is now reflected instead of transmitted. 



It is because of the coloring of the blue, and 

 the transmission of light in countless infinitesi- 

 mal points through it that we fail to appreci- 

 ate its luminosity, and yet next to the sun and 

 its reflections it is the most luminous phenom- 

 enon in the universe. It blinds the light of the 

 stars so that we fail to see them in the daytime, 

 and even the moon looks pale and wan beyond 

 it until the sun has gone down and the light 

 fades out of the atmospheric canopy. Upon 

 the earth its effect is equally apparent. The 

 snow reflects the light of the blue sky like the 

 sheet of paper ; and the white daisies of the 

 meadow, the white foam of the sea, and the sil- 

 ver flash from still waters are but reflections of 

 it. From mountain-heights at twilight one may 

 see below in the valley the thread-like river, the 

 white farm-houses, and the fields of yellow grain 

 showing like spots of light upon the shadowed 



