XXXYI. 



STONE ON A FABM. 



THIS earth, geologists say, was once an immense 

 expanse of heated vapor, which, gradually cooling at 

 its surface, as it whirled and sped through space, con- 

 tracted and formed a crust, which we know as Rock 

 or Stone. This crust has since been broken through, 

 and tilted up into ranges of mountains and hills, by 

 the action of internal fires, by the transmutation jof 

 solid bodies into more expansive gases ; and the frag- 

 ments torn away from the sharper edges of upheaved 

 masses of granite, quartz, or sandstone, having been 

 frozen into icebergs floating, or soon to be so, have 

 been carried all over the surface of our planet, and 

 dropped upon the greater part, as those icebergs were 

 ultimately resolved, by a milder temperature, into 

 flowing water. "When the seas were afterward re- 

 duced nearly or quite to their present limits, and the 

 icebergs restricted to the frigid zones and their vicin- 

 ity, streams had to make their way down the sides of 

 the mountains and hills to the subjacent valleys and 

 plains, sweeping along not merely sand and gravel, 

 but bowlders also, of every size and form, and some- 



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