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PROCEEDINGS OE THE GEOLOGICAL SOCIETY. [Feb. 20, 



They vary altogether from the rocks which occur to the west of 

 them ; and from their nature and position I look upon them as the 

 representatives of the true quartz-rocks. At Ballahulish they are 



Fig. 7. — Section from Glen Coe to Ballahulish. 



E.S.E. 



Glen Coe. Claichig. 



Distance 8 miles. 



W.N.W. 

 Ballahulish. 



Porphyry and Trap-rock. Quartz-rock. Limestone, Schist, 



succeeded by the dark-grey limestone, above which occurs the slate 

 of this locality, having the same direction of inclination — viz. 



§ 9. Section across the Peninsula of Ardsheal from Benivair (fig. 8). 

 — Immediately E. of the inn at Ballahulish syenite again makes its 

 appearance, and this mass of syenite extends S.W. along the coast 

 to near Ardsheal, where it becomes flanked on the coast by meta- 



Fig. 8. — Section of the Ardsheal Peninsula. Distance 3 miles. 



E. W. 

 Benivair. Lhinne Loch. 



' 1 - OVW. 



d. Schist. c. Limestone. a. Quartz-rock. * Syenite and trap-rocks. 



morphic rocks, in the form of quartz-rocks and limestone. On the 

 east of the Ardsheal peninsula the syenite is seen forming the hill of 

 Benivair, against which, on the west, there occurs a mass of quartz- 

 rocks, which, when in proximity to the syenite, contains crystals of 

 felspar, and becomes almost a porphyry. This quartz-rock, more 

 remote from the syenite, is much intersected by joints, and has the 

 stratification very indistinct ; but the lamina? incline at a very high 

 angle, N.W. This quartz-rock at Ardsheal is worked for ceramic pur- 

 poses, and is know minder the name of " china-rock" On its N.W. 

 side it becomes more distinct in its stratification, and is succeeded by 

 a grey limestone, about twelve feet in thickness. Above this lime- 

 stone the dark-grey slates are seen dipping in the same direction ; 

 but on passing over the Ardsheal peninsula, the inclination of these 

 slates becomes reversed. On the western side the quartz-rocks 

 again make their appearance, dipping under the slates ; and these 

 quartz-rocks repose against another mass of syenite, which forms 

 the extreme west of the Ardsheal peninsula. In the west portion 

 of this section no limestone is seen ; and this may either result from 

 the thinning out of the narrow limestone-band, or the limestone may 

 exist, but not be visible, from the covering up of the junctions by soil. 

 The south-east side of the Ardsheal section exhibits the arrange- 



