ROCKS OE THE NORTHERN HIGHLANDS. 383 



high-dipping gneiss, with its overlying green grit, is, by powerful 

 lateral pressure, bent over onto the younger formation. An outlier 

 of the quartzite forms a thin sheet sloping down the south-eastern 

 side of Scounan, corresponding to the patch on the Eagle Rock. 

 These outliers are, of course, the " Upper " Quartzite of authors. 



Section across Coniveall. — As the last section shows us how the 

 Quartzite is brought under the Hebridean, the present one* explains 

 the mode in which the Ben More Grit is thrown onto the Quartzite 



Fig. 6. — Section across Coniveall. (Scale 2 inches to 1 mile.) 



S.W. N.B. 



Brebag. The Balloch. Coniyeall. 



series. High up on Coniveall, as already described, the grit rests hori- 

 zontally upon the gneiss, Following the former towards the west, 

 the beds are observed to gradually rise in dip for some distance in 

 that direction : this fact was independently observed by Mr. Bailey 

 in 1881. Then they bend right over, and plunge down the precipice 

 which overhangs the Balloch. I could not descend the cliff far ; but 

 T was able to trace the beds down for some hundreds of feet with 

 a glass. The upper part of the curve, however, was easily observed ; 

 and the rock was hammered over (No. 94, p. 417). Coming down to 

 the Balloch, to the point vertically under, we find the whole thing- 

 reversed. Green and red grit, in broken masses, passes under gneiss 

 dipping E.N.E. at 70°-80°. All the rocks are much disturbed and 

 crushed; but the main facts are clear. This gneiss is a part of the same 

 spur-like mass which underlies the grit above. The grit is thus seen 

 to form a broken fold overthrown to the west, and enclosing a core of 

 gneiss. On the west side of the pass the Assynt series,- as we have 

 seen, dips towards the gneiss and grit. We can now more fully 

 estimate the difficulties of Murchison's statement that the limestone 

 of the Balloch passes below the " Upper Quartzite" of Ben More. 



This and the preceding section are mutually illustrative. The 

 quartzite in both sections is identical, being continuous in sheets from 



* Compare this section with the description of the western scarp in my 

 observations on the structure of the Assynt mountains. The western and 

 south-western escarpments are on opposite sides of the fault. 



