1865.] The Scenery of Scotland. Ill 



glaciers which once overspread the whole of the lower grounds, as in 

 Greenland at the present day ; the newer which shows rude traces of 

 the Highlands, we are forced to leave the ocean and take to the land ; 

 and here we see agencies actually in operation, either in this or other 

 lands, which in the author's opinion are fully calculated to produce, 

 when acting throughout incalculable ages, that striking variety of 

 mountain and fell, glen and loch, which, when once seen, leaves an 

 impress on the mind never to be effaced. 



Let us now follow the author in his view of the manner in which 

 all this has been brought about. 



Starting with the assumption that the Highlands were raised from 

 the ocean in the form of a plain or table-land, with a few points or 

 lines slightly outstepping the surrounding areas, he supposes that this 

 plain would at once be subjected to atmospheric influences. Rain 

 falling on its surface would form itself into rills, which, uniting into 

 brooks, would then find their easiest way into the sea. A channel 

 once formed, however shallow, would go on increasing in width and 

 depth, and as the land continued to rise, and the action of frost, rain, 

 and stream combined in the work of scooping out and carrying away 

 solid matter, valleys would ultimately be formed, and if valleys, moun- 

 tains ; because mountains of the kind of those in Scotland, Wales, and 

 Norway, may be looked upon with much probability as portions of 

 ancient table-lands, out of which the valleys have been scooped. 



We have thus given a short outline of the views of the author 

 without going into details, which space forbids. For ourselves we 

 are disposed to go a long way in support of them ; though, perhaps, 

 not to the extent of the author himself. That rivers, and even 

 mountain torrents have the power of scooping out channels and valleys 

 of considerable depth and width -is unquestionable; but where the 

 valleys are wide, with very slightly shelving sides which bear no 

 traces of river erosion, but on the other hand preserve the smooth 

 and uniform contour which is presumably the effect of marine denuda- 

 tion, we are at a loss to conceive on what grounds atmospheric agency 

 can be called in here. The case is also strengthened if we find 

 marine stratified deposits of the Drift period occupying such fiats, as 

 is often the case. That these main valleys were formed before the 

 Drift period may be perfectly true, but we base our argument in oppo- 

 sition to the view of progressive atmospheric waste in such instances, 

 on the presence, after so long a period, of these marine deposits. 



In truth, the term " valley " is unfortunately vague, as in many 

 instances one main valley may include several minor ones, and while 

 these latter may owe their origin to one class of agencies, the former 

 may be due to another class. Thus, the greater may be of marine 

 growth, the lesser of fluviatile. A considerable portion of Mr. Geikie's 

 book is necessarily devoted to the description of the glacial phenomena 

 of Scotland in relation to its aspect, and the origin of its lochs, 

 lochans, and sea-lochs or fiords. In this field there have been many 

 fellow- workers ; amongst whom Chambers, Nicol, and Jamieson hold 

 a prominent place. He considers that there are two very distinct 

 kinds of boulder clay : the older being unstratified and due to 



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