104 On the lasaltic Surface of the Counties 



pf which I have already obtained your testimony — I shall 

 venture to proceed, for I am anxious to bring into notice the 

 most complete exposure of the internal structure of a district, 

 that I have seen or read of; as there i9 little likelihood that 

 any other person will enjoy the opportunities which I have 

 had for so many years, of exploring this interesting part of 

 our coast, through a turbulent sea, and rapid tides. 



Description of the Promontory of Bengore, and its 

 Stratification. 



This promontory commences at the termination of Bush- 

 foot Strand, where the coast, the general direction of which 

 for several miles had been due east and west, turns to the 

 north-east, and, after being cut into several semi-circular bays, 

 deflects to the S.S.E. and near the old castle of Dunseverick, 

 resumes its former rectilineal and nearly eastern direction. 



The promontory occupies the interval between Dunscve- 

 rick, and the Black Rock, at the end of Bushfoot Strand, 

 about four English miles; the facades commence at Black 

 Rock, and increase in height until we reach Pleskin, where 

 the perpendicular part at the summit is 170 feet, and the 

 precipitous part from the bottom of the pillars to the sea 200. 

 As we proceed on from Pleskin to Dunseverick, the height 

 gradually abates, and is finally reduced to about 100 feet. 



In this whole space, wherever the precipice is accurately 

 perpendicular, the several strata are easily distinguished from 

 each other, but where the slightest obliquity prevails, a grassy 

 covering is formed that effectually conceals all beneath it; 

 hence the face of the precipice seems much diversified ; the 

 columnar strata in some places only exhibiting detached 

 groups of pillars, while in others they form extensive colon- 

 nades. 



I shall now state the appearances as we approach, and 

 coast the promontory from the westward, noticing in this 

 first view of the precipice, every thing that may be consi- 

 dered as general, and reserving (as I did with you) for my 

 return in the contrary direction, a detailed account of the 

 strata taken separately. 



The first circumstance, that occurs to the attentive ob- 

 server 



