1858,] MUKCHISON NOETHEEN HIGHLANDS, ETC. 36l 



distance eastwards. It will be for future geologists to observe the 

 extent to which this old rock may rise to the day in the central or 

 eastern portions of the Northern Counties of Scotland. For, although 

 I have been unable to detect its reappearance in Sutherland or Eoss- 

 shire to the east of the tracts extending from the west side of Loch 

 Eriboll to Loch Assynt, it may well reappear in various parts of the 

 wild and trackless interior which I have not explored. This old 

 gneiss often occupies platforms of no great altitude, and for the most 

 part constitutes those low, rounded, bare hills which resemble in 

 outline the waves of a rolling sea. The spectator who, ascending to 

 the summit of Ben Stack (one of the loftiest points reached by the 

 old gneiss in Sutherland, and 2363 feet above the sea*), looks west- 

 ward, observes, between him and the sea of Scourie Bay, a countless 

 quantity of small lochs or tarns interspersed among the hollows of 

 this brown-clad barren and rugged waste. On descending to ex- 

 amine the lower tract, he finds the surface frequently rounded off 

 and polished like the "roches moutonnees" of the Alps ; and, obser- 

 ving numerous striae or scratches usually divergent from the central 

 mountains, and following the lines occupied by the principal lakes 

 or maritime fiords, he can have no doubt that, in the glacial period, 

 the North-west of Scotland must have been very much in the present 

 state of Greenland as described by Rink, — i. e. the central moun- 

 tains occupied by snow and ice, from which vast glaciers are pro- 

 truded to the lateral fiords or bays. 



Whether it be examined at Cape Wrath on the shores of Loch 

 Laxford, or in the bold cli£fe near Scourie opposite the Island of 

 Handa, in the Kyles of Strome or in the Bay of Loch Inver, the 

 older gneiss has everywhere the same grey homblendic basis, tra- 

 versed by many veins of bright-pink granite. In ascending from 

 the village of Loch Inver to Drum Swordalan, the geodes and veins 

 of hornblende are indeed so rife as to constitute the chief masses of 

 the rock. 



This old gneiss chiefly occupies the cliffs along the western shore 

 of the Kyle of Durness ; and in a Kttle bum adjacent to the Ferry 

 House, the rock is charged with asbestos and actinolite. 



Cambrian Red Sandstone and Conglomerate of the West Coast. — 

 The ancient gneiss (a) of the general diagram (fig. 1) is seen in 



* By the kindness of Col. James, the Superintendent of the Ordnance Survey, 

 I have been favoured with the following list of the heights of the principal 

 mountains in Sutherland, which cannot but prove useful to the readers of this 

 memoir, and those interested in the physical structure of the North-western 

 Highlands : — 



Feet. 



Ben Chbrig 3157-6 



BenHutig 13400 



Fashven 1495-7 



Cnoc Grhuibhais 975-7 



Suilven 2396-1 



Ben Stack 2363-8 



Carnstackie 2629-2 



SarwhalMore..., 2548-9 



Foinaven 2979-1 



Ben Laoghal 2505-5 



Feet. 



Ben Horn 17084 



Ben Armin 2332-3 



Ben Hie 2862-3 



Ben More in Assynt 3235-5 



Canisp 2780-2 



Ben Spionno 2535-4 



Arkle 2578-3 



Ben Hope 3040-7 



aiashven 2542-9 



Queenaig 26730 



