BOOK OF NATURE LAID OPEN. 177 



ation to the sun, and the dift'erent modifications under 

 which they reflect his light. The various appear- 

 ances and fantastic figures they assume, probably 

 proceed from their loose and voluble texture, revolv- 

 ing into any form by the force or activity of the winds, 

 or by the electricity contained in their substance. 



But, of all the celestial appearances we can behold, 

 what can be compared to the beauty of the rainbow? 

 What a majestic and stupendous arch does this won- 

 derful phenomenon present to our view, and how 

 beautifully is it tinged in regular order, by all the 

 primogenml colours in nature ! 



Yet, this gorgeous arch is instantaneously erected, 

 and at no expense : the commission is sent forth, and 

 it springs into existence, merely by the operation of 

 the sunbeams on the watery particles that float in the 

 atmosphere The rainbow, it must be observed, is 

 always seen in an opposite direction from the sun, 

 and that it is occasioned by the reflection and refrac- 

 tion of his rays, at a certain angle or distance from 

 the eye of the spectator, must be evident to every 

 person who has tried the experiment of the silly boy 

 in the fable, and gone in pursuit of the treasures at 

 the end of it. 



Sometimes, too, we have lunar rainbows; but 

 these shine with inferior lustre ; and what more can 

 we expect from the reflected light of a body, such 

 as the moon that shines itself by reflection? Halos 

 are supposed to be occasioned by the refraction of the 

 light of the sun or moon on. the frozen particles that 

 surround them in frosty weather; and what are called 



