of Derry and Antrim, \o? 



these strata I have nothing to do, limiting myself to those 

 alone of which the promontory is formed, and which' are 

 exhibited in its facades. 



The uppermost of these commences near half a mile to the 

 eastward of the angle, where the coast deflecting from its 

 due east and west course, turns to the north-west, and be- 

 gins to form the promontory. 



So far the course of this stratum is to appearance perfectly 

 horizontal ; for the strata all ascending to the north, the in* 

 tersection of their planes with the plane of the sea must 

 run east and west, that is, in the present case it coincides 

 with the direction of the coast. i 



But when the coast changes its direction, this coincidence 

 ceases, and the facade (that is the vertical section of the 

 coast) losing its east and west course, its strata must appear 

 to ascend towards the point it turns to ; therefore the strata 

 at Porttnoojt, and along the north-east side of the promon- 

 tory, should ascend obliquely along the facades, as they ac- 

 tually do. 



First Stratum, (m). 



The stratum I commence with forms the whole facade, 

 from its first appearance until it reaches the promontory ; it 

 consists of massive pillars rather rude, and about sixty feet 

 long, its course for half a mile (as I have stated) seems ho- 

 rizontal, but on the face of the promontory it ascends, and 

 continues to rise uniformly until it reaches the summit, 

 which it lines as far as Portmoon, on the south side of which 

 it loses some of its thickness^ then suddenly disappears and 

 vanishes from that facade, receding westward in the form of 

 a stony ridge, and is seen no more. 



Second Stratum, (It). 

 The stratum upon which the preceding rests, is red as- 

 brick, and about nine feet thick; it appears in spots and 

 patches just above high water mark, so long as the incum- 

 bent stratum continues horizontal, but when that rises ob- 

 liquely, the second ascends with it ; it is now completely 

 displayed^ and having supported the preceding in its course 



to 



