g t ^^ : .THE SALMON RIVERS OF SCOTLAND 



formation was practically restored. Twice, therefore, have the rivers 

 become formed and twice have our hills and valleys come into being. 

 The more recent valleys did not necessarily follow the former 

 courses ; water did not always eat down into the old channels or 

 keep to more than parts of the old channels. Ice carried great 

 masses of boulders and debris, made huge banks here and over- 

 turned obstacles there. Those causes are responsible for the fact 

 that the main watershed of the country frequently shows no 

 connection with the geological structure, wanders about, as it were, 

 in total disregard of it. 



The most northerly portion of the watershed, viz. that part which 

 is found between Cape Wrath and Knoydart, 1 "coincides pretty 

 closely with the geological strike. It then turns sharply eastward 

 to the line of the Great Glen between Lochs Lochy and Oich. The 

 other portion of the watershed shows a contrasted disregard for 

 geological structure. Sweeping round the head of the Spey valley, 

 and crossing the hills above the head of Loch Laggan, it follows a 

 curving southerly course past the west end of the Moor of Kannoch 

 and the Brae Lyon mountains to Crianlarich, thence across Ben 

 Lomond, until it traverses the great fault and enters the Midland 

 Valley. The farther course of the general watershed of the country 

 may be traced on the map over the Campsie Fells into the wide 

 Lowland Valley, whence, after skirting the south-western parts of 

 Linlithgow and Midlothian, and striking across the Pentland Hills, 

 it runs into the southern uplands between the valleys of the Clyde 

 and Tweed, crossing the Hartfell heights, from which it sweeps 

 across to the Cheviot Hills." 



A glance at the map of the watershed shows how near to the 

 Atlantic seaboard the line keeps in the north of Scotland, and how 

 impossible it is therefore that the rivers in that region can be of any 

 great size. With the first sweep eastwards of the line we have the 

 presence of the largest rivers of the Western Central Highlands, the 

 Lochy, the Spean, and the Awe. With the passage of the line into 

 the Lowlands we have the large river Clyde, still, alas, barred to 

 salmon by the pollutions of Glasgow, pollutions which, under the 

 enlightened modern treatment now in course of development, are 

 steadily diminishing. 



The eastern side of the watershed line contains the great majority 

 of the leading salmon rivers of the country, since the courses of the 

 rivers are longer, and in great measure free from natural obstruc- 



l Siv Archibald Geikie, Scenery of Scotland, p. 169. 



