170 LUNGA. GEOLOGY. 



which lie here buried from view beneath the sea, are 

 also composed of clay slate. This opinion is confirmed 

 by the nature of the intermediate islets and rocks ; 

 which were examined for that purpose. If, either meri- 

 dian lines, or lines on the N. E. by N. rhumb, under 

 which the directions of the strata are all included, be 

 drawn through the several rocks and islands in this 

 sound, it will be seen that the mutual distances of these, 

 on the parallels, scarcely amount to a quarter of a mile 

 in the former case, while in the latter they are nearly 

 coincident. It will also be found that Eilan na gaun, 

 situated near the northern end of the largest division of 

 Lunga, consists entirely of clay slate ; and that the same 

 rock constitutes Balnahua, Blada, an unnamed island to 

 the south of these, and the Isles na kiran which occupy 

 the western shore of Luing. The ridgy forms of the 

 sunk rocks in the intermediate channels, are equally in- 

 dicative of a corresponding composition, and give as 

 complete an insight into the structure of the submarine 

 land as can be expected under similar circumstances ; 

 while they are sufficient to prove a regular sequence 

 from east to west, of the rocks which occur on each 

 side of the chasm formed by the strait of Luing. 



