168 Charles Maclaren, Esq., on G luovtd and Striated Rocks 



ridges of the mountains northward, led me, at first, to think 

 that the protuberances and salient points of the former had 

 been ground off by icebergs. I had then no data in my pos- 

 session, authorising me to conclude that glacieis ever attained 

 the depth of 2400 feet, necessary to cover the ridge on the 

 west side of Loch Lomond ; but the objection on this ground 

 is now removed. The able French geologist named (M. 

 Martins), has found traces of an ancient glacier on the Alps, 

 758 metres (2468 English feet) above the bottom of the 

 valley which contained it. There is no difficulty now, there- 

 fore, in admitting, that a glacier might abrade the surfaces 

 of the highest of these ridges. 



Loch Eck — Arrow 6. — The rocks on the two sides of this 

 Joch are smoothed and rounded off in a manner so conspi- 

 cuous, that it cannot fail to strike the most careless ob- 

 server. In a hasty journey through it, I saw no striae ; but 

 the coarse surface of the slate is ill fitted to shew them. 

 Dome- shaped rocks, however, with one side rough, clearly 

 shew that the abrading agent moved in the same direction 

 as at Gareloch, — namely, SSE. 



Loch Fine — Arrow 5. — I found some distinct groovings on 

 the beach at St Catherines, opposite Inverary. Their bear- 

 ing v,as conformable to that of the loch, or about SSW. 

 It is worth remarking that thei'e is a bifurcation here, caused 

 by the meeting of two valleys, in the form of Y, like that 

 which occurs at the junction of Loch Long and Loch Goil. 



Loch A7ve — Arrow 4. — Smoothed rocks of gneiss are 

 numerous at the foot of the hill of Stobacherachrun, on the 

 north side of the loch, and many of the islets in it seem to 

 be low, abraded domes. On the south side of the loch, about 

 a mile west from Dalmally Inn, there are two little hills on 

 the right and left sides of the road, which exhibit the crag- 

 and-tail form, on a small scale, in a position the reverse of 

 that we are accustomed to. The east side of each is laid 

 bare and smoothed, \v'hile a mass of stones and soil covers 

 the west side. On the face of the hill lying on the left or 

 south side of the road, I found a few grooves, which pointed 

 ENE. and WSW. Taken in connection with the crag- 

 and-tail, they indicate that the abrasion and grooving were 



