THE FRESH- WATER LOCHS OF SCOTLAND. 287 



Regarding the lines of displacement in the Conon basin, one of the 

 most important is that just referred to, which skirts the base of the Black 

 Isle, and is prolonged north-east to Tarbat Ness, whereby this straight 

 feature has been determined. The great fault that traverses Loch 

 Maree and Glen Docharty passes south-east by Ledgown, thence across 

 the watershed by Carn Chaorainn to Loch Beannachan in the basin if 

 the Meig. Another powerful dislocation, nearly at right angles to the 

 course of the Loch Maree fault, has determined the north-north-east 

 direction of the Meig valley between Inbhir-Chaorainn and Milton 

 of Strathconon, and stretches south-west up Glen Chaorainn in the 

 direction of Loch Monar, and north-north-east to the head of Loch 

 Luichart. 



During the period of extreme glaciation it would appear that the 

 ice-shed lay some distance to the east of the existing watershed in part 

 of the Conon basin, for boulders of foliated granite or augen gneiss, 

 from one or other of the masses near Inchbae, have been carried west- 

 ward into the valley of Loch Broom, to Inverlael, and nearly as far as 

 Ullapool. Their distribution in an eastward direction is no less 

 remarkable, for they have been traced as erratics across the Black 

 Isle and the Moray firth to the plain of Moray and the low grounds of 

 Banff shire. The boulder clay of the north part of the Black Isle 

 contains numerous blocks of this well-known rock, which were probably 

 dispersed during the greatest extension of the ice. Such evidence is in 

 harmony with that obtained in the Assynt district, where blocks of the 

 eastern schists have been carried from the plateau of the Moine schists, 

 east of the existing watershed, to higher elevations to the west, formed 

 of Cambrian strata. In view of these facts, it seems probable that 

 during one stage of the glacial period the Conon basin must have been 

 buried under an ice-sheet that overtopped the highest hills, the move- 

 ment of which was largely independent of the physical features of the 

 region. 



During the period of confluent glaciers that ensued, the great 

 mountain groups formed more or less independent centres of dispersion. 

 Indeed, many of the striae, the disposition of the moraines, and the 

 distribution of the carried blocks furnish evidence relating to this 

 phase of glaciation. In the Fannich mountains a range running east 

 and west for about 7 miles, and whose main peaks rise above 3000 feet 

 ice-markings were found on the southern slopes at elevations between 

 2250 and 2500 feet trending south-south-east. Striae pointing in a 

 similar direction occur at various points on the ridge between Loch 

 Fannich and Strath Bran, thus showing that at one period the Fannich 

 ice must have crossed that loch into the Bran valley. Again, during 

 this later glaciation, ice crossed the watersheds from Glen Fhiodaig 

 and from Strath Conon into the valley of the Bran, and after uniting 

 with the glaciers from Fannich and the Blackwater, passed eastwards 



