RASAY. GEOLOGY. 245 



this with the former red sandstone, as a portion of a line 

 extending round the east side of the island, the remainder 

 of which, to the southward, will be immediately described. 

 In this respect it becomes interesting, as it might other- 

 wise remain a doubt incapable of solution, whether the 

 northern and southern red sandstone of Rasay were parts 

 of the same deposit ; and, consequently, what relation 

 the northern portion bore to the more distant rocks of the 

 same nature to which I have already alluded. 



The extent and position of the last and southern division 

 of this rock are also marked on the map, where it is seen 

 lying opposite to the neighbouring shore of Scalpa. The 

 line of direction here undergoes a change, becoming more 

 easterly and appearing to lie about N. E. by E. ; although, 

 from the imperfect manner in which it is displayed, this 

 cannot be precisely ascertained. If it be as here stated, 

 it approaches more nearly to the direction of the same 

 rock on the shore of Scalpa, the line of bearing being 

 there N. E. half E. Considering the proximity of these 

 coasts, and the continuous extent of this rock to the 

 southward, it is probable that, on both, it belongs to a 

 common deposit ; and that these detached portions are 

 connected by a regular succession of beds in those parts 

 of the surface which are invisible by reason of the inter- 

 vening sea. It must nevertheless be remarked, that while 

 the dip of this sandstone in Rasay is uniformly towards 

 the west, it varies in Scalpa ; a circumstance however 

 which will not invalidate that conjecture, as in Sky, the 

 same rock is subject to frequent and even sudden reversals 

 of position. To extend the analogy between this southern 

 portion of sandstone and the two already described, I may 

 add, that, like these, it is immediately followed by the 

 same strata of white sandstone. 



In recurring to the differences of direction of the strata 

 in these three portions, it will be seen that they amount 

 to six points of the compass, or upwards of 60. If 



