716 Beviews. [Oct. 



rains, torrents, and rivers, to channel out the valleys of mountainous 

 regions. "Only give me time," he says, in so many words, "and I 

 can remove mountains." Nor is it necessary to remind our readers 

 that the geologist takes as much time as he pleases whether it is given 

 to him or not. 



The earlier pages of Mr. Geikie's work contain an interesting 

 account of the rapid waste which the eastern coast of Scotland has 

 undergone within historic times. Along some parts this waste is 

 alarmingly rapid. Villages, churches, castles, farms, of whose former 

 existence there is historic record, have disappeared before the 

 ceaseless attacks of the waves, so that, contrary to the popular 

 notion, this coast is wearing away with much greater rapidity than 

 the western. The process of decay is also facilitated by the generally 

 softer nature of the rocks on the eastern coast, a considerable length 

 of which is formed of Old Eed Sandstone. On the western side, the 

 parts which are most frequently exposed to the attacks of the Atlantic 

 breakers, are composed of tough gneissose or slaty rocks, admirably 

 adapted for resisting disintegration, while the long chain of the 

 Hebrides, stretching athwart the coast, acts in some degree as a 

 natural breakwater to the mainland. 



Mr. Geikie divides the surface of the country into three physically 

 distinct regions — the Highlands, the Central Valley, and the Southern 

 Uplands — each of which he treats of separately. He considers that 

 about the commencement of the period of the Old Eed Sandstone the 

 highlands began to appear from below the sea in the form of an un- 

 dulating plain with occasional prominences. This was "a plain of 

 marine denudation." Thus far the author only recapitulates the views 

 of Murchison, Sedgwick, Nicol, and other geologists. But now arises 

 the question, How, out of such a plain, were the mountains and valleys 

 formed ? Was it by the upheaval of some special lines and the de- 

 pression of others, assisted by the action of the waves and currents as 

 the land continued to rise above the level of the sea ? Or, on the other 

 hand, has the result been brought about by atmospheric agencies? 

 Now, while admitting that the occasional displacements of the strata 

 by faults, and minor elevations and subsidences, may have had some 

 slight effect in originating lines of hill and valley, and also that the 

 sea had its due influence, the author regards the atmospheric agencies 

 as by far the most powerful. To the former view there is this serious 

 objection — that the action of the sea tends invariably to level all 

 opposing barriers, and to reduce the surface to one nearly uniform 

 plain. Nor is it conceivable that the sea could produce valleys of the 

 kind which occur in the Western Highlands, or the firths and sea-lochs 

 which pierce the coast all along its margin from Cape Wrath to the 

 Clyde. A glance at a well-shaded map (such as that which accom- 

 panies this volume) will serve to show that the sea-lochs are generally 

 continuous with the valleys or glens of the land, and that they are 

 to be considered only in the light of submerged valleys. In proof of 

 this Mr. Geikie adduces what to our mind seems conclusive evidence 

 in the fact, that they contain in some places " rock-basins." 



In seeking, then, for a cause sufficient to account for the scenery of 



