238 BATHYMETRICAL SURVEY OF 



of the glacial period, even the highest mountains in the Loch Maree 

 district were overridden by the ice. Some of the evidence pointing to 

 this conclusion may here be referred to. Along the top of Ben Slioch 

 (3217 feet), which, as already indicated, is composed of Torridon Sand- 

 stone, blocks of thrust Archaean gneiss, Cambrian quartzite, and 

 Moine schists are met with, all of which have been derived from the 

 east. Similar evidence is obtained on Meall Ghuibhais (2882 feet), on 

 the south side of Loch Maree. Again, in the Coulin forest, on the lofty 

 ridge running south from Sgurr Dubh (2566 feet) to Beinn Liath Mhor 

 (3034 feet), striae have been recorded pointing in a westerly direction at 

 elevations ranging from 1750 to 2000 feet. Blocks of crystalline schist 

 derived from the area east of the Moine thrust, and occasional frag- 

 ments of thrust Archaean gneiss, appear on this ridge. Further south 

 on Sgurr Ruadh, ice-markings pointing a few degrees to the north of 

 west occur at an elevation of 2500 feet. The top of Ruadh Stac (2919 

 feet), on the east side of Glen Kishorn, is finely glaciated, the striae 

 pointing W. 25 N. The summit of Meall a' Chinn Dearg (3095 feet), 

 composed chiefly of Torridon Sandstones and grits, is strewn with 

 transported blocks of Cambrian quartzite. Similar evidence might be 

 adduced regarding that part of the Applecross area which is shown in 

 the south-west corner of the map. For there, on Beinn Bhan (2936 

 feet), striae have been recorded underneath the 2750 feet contour-line 

 trending W. 13 to 20 N. Blocks of the Eastern or Moine schists 

 appear at that level, and are fairly plentiful below 2500 feet. From 

 these facts the inference seems obvious that during the maximum 

 glaciation the western part of Ross-shire must have been completely 

 overridden by ice moving in a westerly direction towards the sea. 



The westerly flow of the ice is confirmed by the transport of the 

 boulders in the drift deposits, which consist mainly of moraines in the 

 area lying to the west of the Moine schists, and these contain numerous 

 blocks of quartzose-schist and mica-schist derived from the east. 



After the disappearance of the great ice-sheet there ensued a period 

 of confluent valley glaciers. The direction of the ice-flow during this 

 later glaciation is represented on the map by feathered arrows. On 

 referring to the map, it will be seen that the prominent mountain 

 groups north and south of Loch Maree formed independent centres of 

 glaciation. In many of the valleys there is a splendid development of 

 both lateral and terminal moraines. The closing phases of the glaciation 

 of the region are indicated by the moraines encircling some of the high 

 corries, and by similar deposits resting on the 50-feet beach at the head 

 of Loch Torridon, where they have been recorded by our colleague, 

 Mr. Hinxman. 



A glance at the map will show that Loch Maree is by far the largest 

 rock basin in that district ; but as it lies along the line of a powerful 

 fault, which has given rise to a prominent feature in the topography 



