﻿92 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



[Dec. 5, 



30° N., but below decreases to 15° or 20°, and the beds are broken 

 and irregular. Lower down, the burn tumbles over a thick mass of 



Pig. 5. — Section near Emboli House. 

 w. a E. 



d. Limestone. c 2 . Fucoid-beds. 



c x - Quartzite. c 1 . Quartzite. 



a. Mica- and talc-slate, with granitoid veins. 



quartzite, very indistinctly stratified, but apparently dipping at 66°, 

 to S. 10° E., and resting on the red fucoid-beds (c 2 ) dipping at 50°, 

 to E. 20°-30° N. Below tbem is a bed of hard reddish quartzite 

 (c*) dipping 35°, to E. 20° S. ; and further down the common dark 

 bluish-grey limestone, much fissured and contorted, but with a dip 

 of about 68°, to E. 30° S. The limestone appears to form all the 

 under part of the hill and the low ground to the loch. In this 

 place the quartzite appears to rest on the limestone and dip below 

 the mica-slate, but the succession of the groups shows clearly that 

 this is the result of an upheaval and inversion of the strata. The 

 regular order in the whole north-west of Scotland, from Durness to 

 Loch Keeshorn, is quartzite (c 1 ), fucoid-beds (<r), and limestone (d) ; 

 and we must either admit this inversion, or make the improbable 

 assumption that the succession of the deposits has been completely 

 reversed in the space of a few hundred yards, and only in this very 

 limited zone along the declivity of this ridge. 



The same relation of the beds is seen near the Ault-na-harrow 

 road, though, from the more powerful intrusion of the igneous rock, 

 the strata are more irregular in dip and more highly contorted near 

 the line of junction. The quartzite is so compact as to resemble 

 calcedony, and shows no marks of bedding. The fucoid-beds and 

 limestone are in some places nearly vertical, in others more horizon- 

 tal. The fine-grained talcose mica-slates also, which near* the 

 quartzite and intrusive rock dip at 35° and 30°, to E. 60° S., further 

 east dip at 10° or 5°, to E. or E. 15° S. Over the hill, towards 

 Loch Hope, the dip becomes even lower, so that the undulations of 

 the strata cause them in many places to dip to the west. 



Overlying Red Sandstone and Quartzite of Tongue. — Another 

 proof of the true succession of the formations in the north of 

 Sutherland appears in the vicinity of Tongue, about eight or ten 



