of Berry and Antrim. 201 



less than a mile ; but when we find at Port-moon a succession 

 of three strata with the same inclination, in the same order, 

 of the same thickness each, and with the same strong cha- 

 racteristic marks that distinguished the three interrupted, at 

 the depression ; above all, when we find the strata they rest 

 upon continuous (at least with very trifling interruptions) 

 for the same extent ; I think we. can scarcely entertain a 

 doubt that this interval between the corresponding parts, 

 though so m;ich greater than any of the preceding, is, like 

 then), but an interruption, and that these strata -were once 

 continuous from the depression to Portmoon, 



The same style of induction would establish the quondam 

 continuity of all the strata in the face of Bengore promon- 

 tory, for here the strata are so distinctly marked that we 

 know each of them when we find it again after any inter- 

 ruption. 



In the rest of our precipices and facades, the similarity of 

 the strata deprives us of this advantage; yet in their smaller 

 interruptions, the eye, by tracing the rectilineal course of 

 the strata, and so connecting the separated parts, can esta- 

 blish their former continuity : while in the greater intervals 

 we must rest our proof on analogy alone. 



That we may be entitled to carry this style of induction 

 into the interior of our basaltic area, and to apply the same 

 reasoning to enable us to form a similar decision upon the 

 more stupendous interruptions of our strata, which I have 

 already enumerated, it becomes necessary to explain the geo- 

 logical construction of our area, — the strata of which it is 

 formed — their arrangement — and their inclinations. 



An extensive limestone stratum, white as chalk, and about 

 two hundred feet thick, seems to form the base of the whole 

 district I limit myself to : upon this, accumulations of rec- 

 tilineal and parallel basaltic strata, are heaped up to most 

 unequal heights. 



This great calcareous stratum seems not to be an accurate 

 plane, but rather to resemble a bason, as every where at its 

 periphery it dips to the interior ; yet the plane of its section 

 has a slight ascent to the southward : a recollection of these 

 circumstances will enable us to account for every appearance 



this 



