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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



[Feb. 20, 



Earn head, this same gneiss also makes its appearance, dipping in 

 the same direction at an angle of 20° ; and at the bridge, about a 

 mile north of Loch Earn head, a hard trap occurs, from which the 



Eig. 2. — Section from Loch Earn to Loch Tay. Distance 6 miles, 

 s. N. 

 Dall. Glen Ogle. Larigellie Loch. Dochart River. 



Limestone 



* Trap-rocks. 



metamorphic strata seem to derive the E.S.E. inclination. On the 

 north side of this mass of trap, which is much intersected by quartz- 

 veins, a reversed dip is seen and N.W. inclinations obtain. 



Along Glen Ogle, the gneiss, which is micaceous, is only slightly 

 inclined, and has quartz-veins running along the lines of stratifi- 

 cation. At Larigellie Loch, a small lake near the water-shed of 

 Glen Ogle, the E.S.E. dips become most prevalent; and these con- 

 tinue to the shepherd's cottage, where limestone again occurs, 

 dipping at an angle of about 40° E.S.E. This limestone is seen along 

 the course of the Larigellie Burn, where it becomes flattened ; and 

 at the bridge, where the high road crosses this stream, about a mile 

 and a half from Killin, another mass of trap makes its appearance. 

 In the arrangement of the strata in the section between Loch Earn 

 and Loch Tay, we have a mass of limestone near Loch Earn which 

 underlies the gneissose rocks, and near Loch Tay gneissose rocks 

 are seen, superimposed also in limestone. This limestone, as seen 

 in the Larigellie Burn, seems to form a rounded anticlinal; for, 

 immediately on its north side, we have gneissose rocks amply deve- 

 loped in the Biver Dochart, and these dip N.W. at an angle of 20°. 



§ 4. Sections from Loch Tay to Glen Lyon (fig. 3). — The rocks just 

 referred to, as seen in the Dochart, also appear on the road from 



Fig. 3. — Section from Loch Tay to Glen Lyon. Distance 9 miles, 

 s. n. 



Loch Tay. Loch-a-Larich. Glen Lyon. 



d. Gneiss. 



c. Limestone. 



a. Quartz-rock. 



'■ a f 

 f. Fault. 



d 



Killin to Lochie Bridge, and for a short distance along the road to 

 the eastward, having the same N.W. inclination. About half a 

 mile east of Lochie Bridge strata of limestone occur, having thin 

 bands of rotten gneiss interstratified ; the limestone is also thin- 

 bedded. These limestones dip N.N.W. at 60°. At Mornish, 

 about two miles east from Killin, similar limestones also occur. 

 They have, however, a gneissose aspect, and are greatly con- 

 torted ; but still the prevailing dip (N.N.W.) of this portion of 



