ON THE EARTH'S HISTORY 



moved from the rocks of England and Wales in one year. 

 That is equivalent to a general lowering of the surface 

 of the country, by chemical solution alone, at the rate 

 of one foot in 13,000 years. That is not much, it may 

 seem ; but in a million years, which is not a long period 

 in geological time, half the present towns of England 

 would be sunk under water by this cause alone. 



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