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the Ordnance Geological Survey, assuring this Society, that having 

 during the past year, for the first time, seen the practical application 

 of the admirable meihod of field-survey which has been instituted 

 by Sir Henry De la Beche, I am convinced that it will not only act 

 directly as a great national benefit, in making more correctly known 

 the structure of the subsoil, in a manner beyond the reach of private 

 enterprise, but that it will materially tend to elevate Geology, by 

 connecting it in a permanent manner with Physical Science, 

 . Rocks of the Scottish Border.— A memoir by Mr. W, Stevenson 

 on the Geology of Berwickshire appears to me to be worthy of com- 

 mendation, from the perspicuity with which he treats a diifficult 

 subject in this his first production. In consequence of a notice in 

 the work of Mr. Hugh Miller on the Scottish Old Red Sandstone, 

 that Mr. Stevenson had discovered ichthyolites in that rock near 

 his native town of Dunse, I made an excursion thither during the last 

 summer, from the east coast of Berwickshire, which I was examining 

 in company with my friend Count Keyserling. Having visited the; 

 localities of the Old Red fossils, and made the acquaintance of Mr, 

 Stevenson, I pei-ceived that he had clearly worked out the leading 

 phsenomena of the border country, and I therefore urged hifn to 

 prepare the paper which has been I'ead before you. 



Notwithstanding the memoirs of Mr. Winch, Mr. N, Wood, and 

 Mr. Witham, on the Carboniferous rocks of Northumberland and 

 the borders, and of the excellent work of Mr. D. Milne on Berwick- 

 shire, no portion of the British Isles more required surveying, than 

 the tract on both sides of the river Tweed, from its mouth upwards. 

 The very clear section laid open by lowering the high road in its 

 descent from Belford to the town of Berwick, had, it is true, com- 

 pletely satisfied every one who had seen it, that of the Berwick- 

 shire coal-seams (seven of which are worked), some are subordi- 

 nate to the lowest beds of the mountain limestone series, and that 

 others are far below it. Having confirmed the views of Mr. Witham, 

 my fellow-traveller and myself worked out this point further, by 

 following the coast from Berwick northwards to Bourne Mouth, 

 and. by ascertaining that the coal-beds beneath the Laraberton 

 Cliffs (and others are still lower) are at considerable depths under 

 the lowest band of limestone, containing Product! and shells of 

 the carboniferous limestone ; in short, that they form part of a red 

 sandstone group, in which the plants of the Carboniferous systeni 

 prevailed. Unluckily, the regular descending sequence from these 

 lowest red coal-fields into the deposits of old red sandstone, pro» 

 perly so called, has not yet been noticed on the sea-coast, nor is it 

 probable that such passage can there be detected, owing to a great 

 dislocation which has thrown the lower carboniferous strata into a 

 vertical position against metamorphic greywacke and trappean rocks. 



Unacquainted with these coast-sections, Mr, Stevenson has, how- 

 ever, made out in the interior, and from comparatively obscure data, 

 a natural ascending succession from the nonfossiliferous slaty I'ocks 

 of the Lammermuir Hills, through the old red sandstone, to the base 

 of the productive coal-field above alluded to. The old red sand- 



