198 Dr. Richardson’s Letter on the basaltic Surface 
has here, as at Pleskin, attained the height of three hundred 
feet above the water. 
This seventh stratum, like those above it, also suffers an in- 
terruption ; for after having exhibited itself to such great advan- 
tage at Bengore, the extreme northern point of the promon- 
tory 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 perpendicularity it is 
little seen, and is finally lost over the causeway, we know not 
well how. 
Eighth Stratum, (c). 
The next stratum is of the same variety of basalt with the 
third, that is, irregular prismatic ; it is fifty-four feet thick, 
and in the views distinguished by the letter ( c ) : where it 
emerges at the south east corner of Portmoon, it is quite acces- 
sible by land, and affords the best opportunity I know for 
examining this species of basalt, as it is there very neat. 
There is little more of this stratum seen in the facade of 
Portmoon for want of perpendicularit}q but it forms the lower 
frustum of the great conical island Beanyn Daana , and the 
whole of the smaller, except the base ; it is well displayed 
over the remainder of the precipice, it forms the intermediate 
stratum between the magnificent colonnades at both Bengore 
and Pleskin, and finally is lost just over the Giant’s Causeway. 
Large globular fragments have fallen from it, and are scat- 
tered about the causeway. 
