DOMAIN XI. DECOMPOSED. 



limestone ; many of them are not much 

 vvorn, and cannot have travelled far from 

 ;he rock in which they were originally con- 

 fined. It seems certain, therefore, that 

 liey are the debris of limestone strata, now 

 entirely decomposed, that once lay above 

 he strata, which at present form the base 

 >f this elevated plain, and probably cover- 

 ed them to a considerable height. This 

 xplanation carries the greater probability 

 ith it, that any other way of accounting 

 >r the fact in question, as the travelling 

 f the gravel from higher grounds, or the 

 nmersion of the surface under the sea, 

 ill imply changes in the face of the coun- 

 y, incomparably greater than are here 

 ipposed. Our hypothesis seems to give 

 minimum of all the kinds of change 

 lat can possibly account for the pheno- 

 menon. 



" The same remarks may be made on 

 le high plain of Blackdown, which the 

 >ad passes over in going from Exeter to 

 westward. The flints there are disse- 



