220 



(2.) With regard to the action of tides in fissures : This 

 theory depends upon the question, whether there ever were any 

 considerable fissures in existence in the Cotteswolds adapted to 

 the admission of tides. I think not. The action of the sea as 

 the land rose would scarcely admit of such a state of things. 

 If the fractures had opened to any extent, they would be filled 

 with the detritus of the denuded strata, as the waves rolled 

 over the surface and ground the soft Oolite into sand. Again : 

 if during upheaval the tides acted in fissures, the upper parts of 

 the valleys, instead of being, as we find them, mere undulations 

 of the surface, would be wide and deep, and every valley should 

 commence in a ravine, and not as a gentle slope. 



In opposition to the theory of fissures, I may throw out the 

 suggestion, that those fractures of which we have evidence 

 may be attributable, not to the dislocations produced in the 

 course of upheaval, but to the strain upon the surface in 

 consequence of the subsidence of the adjacent land during the 

 glacial epoch; certainly the numerous faults in the Cotteswolds, 

 as traced on the map, generally run from East to West, and 

 this is consistent with the idea of their having been caused 

 by the great subsidence of the country northwards. Of 

 course this hypothesis militates against that of tidal action 

 in the valleys; because if the Cotteswolds were high above 

 the sea during the period of submergence, the fissures, if 

 formed as suggested, would be beyond the reach of tides. If it 

 is contended that the valleys were formed by marine agency, 

 some direct and positive evidence should be adduced in support 

 of that view of the subject. 



Considering that the evidence of marine action is in the 

 highest degree unsatisfactory, I am incHned to the opinion that 

 the formation of the valleys is the result of sub-serial denudation, 

 including springs and rivers, in combination with landsHps, and 

 to assign to the same agencies some portion of the denudation 

 of the VaUey of the Severn; and if, on investigation, it is found 

 that these causes are sufficient to accoimt for the changes which 

 have taken place in the aspect of the country, it is fair to assert 



