110 On the basaltic Surface of the Co?mties 



appear in a desultory way on the summit of the precipice, 

 wherever it is of sufficient height to receive them, always 

 preserving their usual thickness, their characters, and their 

 order ; so that a person master of the order I am detailing, 

 as he approaches a rising point of the precipice, can tell its 

 strata, and their order, before he is near enough to distill* 

 guish them. 



Seventh Stratum, (d). 



The rude and massive pillars of the sixth stratum pass into 

 the neater, and much longer columns of the seventh, without 

 interrupting the solidity or continuity of the material ; exact- 

 ly as a down-held hand appears to separate into fingers. The 

 thickness of this stratum, that is the length of the pillars of 

 which it is formed, is fifty -four feet ; it is marked {d) in the 

 two views, and in its passage across the face of the precipice, 

 displays more beautiful colonnades than any of the others. 



This seventh stratum emerges from the beach immediately 

 behind the south-east point of Portrnoon, and where it first 

 shows itself in that bay, has its lower edge raised only a few 

 feet above the water ; it forms the upper frustum of the 

 larger of the two conical islands, ascends obliquely along 

 the face of Portrnoon, and continues to rise until it com- 

 poses the upper range in the beautiful facade, properly called 

 Bengore Head. This is probably the most magnificent of all, 

 its convexity towards the sea producing a fine effect. The 

 lower edc;e of this stratum, that is the line forming the base 

 of its pillars, has here, as at Pleskin, attained the height of 

 three hundred feet above the water. 



The seventh stratum, like those above it, also suffers an 

 interruption; for after having exhibited itself to such great 

 advantage at Bengore, the extreme northern point of the 

 promontory lowers, and this stratum disappears for about 

 one-third of a mile ; as the promontory rises, it is resumed 

 again in great beauty at Pleskin, and is interrupted no more; 

 we scarcely ever lose sight of it until we reach Port Noffer 

 (the next bay to the Causeway) ; here, for want of perpen- 

 dicularity it is little seen, and is finally lost over the cause- 

 way, we know not well how. 



Eighth 



