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wild, and picturesque, and the botanist, than it will the geologist. 

 Still there is the slate to study; the whole walk is upon slate ; and 

 the many changes in its mineral character, the effects of former sea 

 action upon it, as shown in the ancient cliff, which in some places 

 advances boldly on the shore, and in others retires inland, and as 

 compared with the like action on the sandstone, will form interesting 

 subjects of inquiry. Abrupt changes in dip will be noticed in the 

 slate, at the north side of Glen Catacol. With the exception of a few 

 singular inversions, due, probably, to dikes, it maintains a pretty 

 uniform dip and inclination, 40 E. of S. at about 40, till we approach 

 Glen Catacol, north of which an anticlinal seems to occur, owing to 

 an advance of the granite in the direction of the bay. On one 

 side the slate rises up towards the granite, as if thrown off from it, 

 the dip being 65 W. of N. at 53; on the other it dips E. and S.E., 

 at about 30 to 40. But this dip is not maintained ; it is some- 

 times directed towards the granite, in other places, " end on " to it, 

 or southward, and in others again off the nucleus, or nearly west; 

 but there is never exhibited that mantling stratification around the 

 nucleus which is usually seen in granite tracts. 



It is only on this extreme north-western border of the slate tract 

 that the micaceous character which prevails in Cantire is assumed 

 by the slate. Near the Free Church, which stands on a lovely 

 picturesque spot in North Thundergay, a fine mica slate, banded 

 with quartz, occurs ; east of this there is much chlorite slate, and 

 one mile west of it, near the secluded burying-ground, blue argil- 

 laceous slate, mixed with the chloritic variety. But generally 

 there is on this side a greater tendency to the micaceous character. 

 On the Imochair shore, and towards Dugarry, the ordinary character 

 has become again established. There are comparatively few dikes 

 on this coast. A little east of the Free Church there are two, each 

 of which appears to bifurcate. On the Penrioch shore a great bed 

 of greenstone, 100 feet broad, occurs. We did not notice a single 

 bed either of porphyry or claystone. Many boulders of granite 

 occur; northwards they are of the coarse-grained variety, but of 

 both varieties on the South Thundergay and Penrioch shores. A 

 few were estimated at as much as twenty to thirty tons weight. 



As the coast from South Thundergay southward, is somewhat 

 monotonous, we would recommend the tourist, if the day be clear 

 and steady, and he has had an early start, to diverge inland at South 

 Thundergay, visit the lovely and secluded corrie and tarn, called 

 Corrie-an-Lachan (hollow of the lake), ascend Ben-Varen from the 

 north, pass along its eastern ridge, and descend upon lorsa water- 



