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of the strata immediately adjoining ; and to go a step further, 

 we arrive at the conclusion that the folding back of this 

 immense mass of rock and the consequent lateral pressure pro- 

 duced have caused that remarkable overlapping of the strata 

 in the interior of the basin which I have already described. 



The view here advanced will be greatly strengthened, and 

 we shall be led to certain useful practical deductions from it, 

 by a consideration of the following circumstances. If we ex- 

 amine Mr. Saunders' geological map of the neighbourhood we 

 shall find that where, as at Ashwick, the angle of inclination 

 in the limestone is not more than from 40 to 50 degrees, the 

 coal measures opposite have their true northern dip ; but that 

 when we proceed a little farther eastward to Stoke Lane, where 

 tbe inclination of the limestone has increased to 70 or 80 

 degrees we find simultaneously mth it the abnormal southern 

 dip. It will also be observed that if at the point where the 

 contrary dip sets in, a line at right angles with the range of 

 the Mendips is extended into the interior of the coal basin, it 

 will intersect the western termination of the overlap fault so 

 far as at present known. If, then, the western termination of 

 the overlap, the folded coal measures, and the highly inclined 

 limestones so nearly coincide, is it not a strong argument in 

 favour of one common origin, and is it not fair to assume that 

 by observing the inclination of the limestone to the eastward 

 we may ascertain approximately the eastern termination of 

 the overlap and the folded strata of which we are at present 

 in ignorance ? High angles prevail in the Mendips until we 

 reach the eastern side of Mells Park, and it is to be expected 

 that to that point the disturbances alluded to will hold good, 

 but after passing the village of Mells the inclination rapidly 

 decreases to 50 degrees. Near that point therefore we may 

 expect the strata to recover their legitimate dip, and at right 

 angles to it in the interior of the basin we may hope to dis- 

 cover the eastern termination of the overlap fault. 



