RASAY. GEOLOGY. 243 



account of the regular bearing of the strata that imme- 

 diately follow it, we should have expected to find an un- 

 interrupted mass of sandstone. On the eastern side of the 

 island it appears to be disposed in beds of considerable 

 regularity, conforming to the sandstone, lying with their 

 elevated edges, as nearly as could be ascertained, in the 

 direction of N. by W., and dipping E. by N. The angle 

 may be taken on an average at 40. I do not speak with 

 confidence respecting the direction of the gneiss, since it 

 does not appear to be disposed with that linear exactness 

 so remarkable in Sky, nor, as in that island, to run with 

 the same parallel nicety to the sandstone. On the con- 

 trary, in many places, and particularly towards the nor- 

 thern extremity of the island, its position becomes uncer- 

 tain and irregular as in Rona. 



Having given a sufficient description of the mineral 

 characters of this rock when speaking of Rona, with 

 which Rasay is geologically continuous, I shall here 

 content myself with barely mentioning that, in addition 

 to those, it exhibits various alternations of hornblende 

 schist and of the various compounds which have already 

 so often fallen under review in describing the westernmost 

 chain of islands. 



The red sandstone, commencing where the gneiss 

 terminates, is disposed, as far as its boundary is con- 

 cerned, in the same linear direction, with the exceptions 

 already noticed ; that line being nearly N. by W. : but 

 the nature of the ground, which often prevents the 

 elevated edges from being seen, prevents also the con- 

 tact from being ascertained. The direction of the strata 

 follows that of the boundary, and appears, throughout 

 the whole space occupied by this rock, to be N. by W., 

 although in some places it seems to become occa- 

 sionally N. and N.N.W.; variations, if they really exist, 

 arising in all probability from those undulations to which 

 strata are so often subject. It exhibits the same regularity 

 on the western as on the eastern side of the island ; and, 



