Geological Fotes. By G. A. Lebour, M.A., F.G.S. 527 



is true, from our centre, Elsdon, but still •within tbe prescribed 

 five miles. (2) 



Boulder Clay and its immediate product Re-assorted Boulder 

 Clay do not, fortunately for the geologist, cover much ground 

 about Elsdon. They are found, however, in patches obscuring 

 the lower slopes of the valleys, and often forming the concave 

 curve at the foot of the hills, but being generally covered with 

 grass it is only where a road cutting or a broken burn-bank ex- 

 poses the glacial beds, that the polished and scratched boulders 

 attesting their age can be seen in their stiff clay matrix. 



The Lower Carboniferous Bochs however furnish the stone frame- 

 work of the entire district. This great division, it will be re- 

 membered, has been in Northumberland, the ancient Bernicia, 

 split into two members, the Bernician above, regarded as the 

 equivalent of the Carboniferous or Mountain Limestone Series of 

 the more southern parts of England, and the Tuedian below, the 

 equivalent of the Calciferous Sandstone Series and part (at least) 

 of the Upper Old Eed Sandstone of Scotland. (3) Of these the 

 Bernician Series is alone represented in the tract of country under 

 notice, and part of that series only, viz. : the Lower Bernician. This 

 Bernician Series, both upper and lower, consists of beds very sim- 

 ilar throughout, grits and sandstone predominating (and thus 

 sufl&ciently putting such names as Carboniferous Limestone Series 

 and Mountain Limestone, out of court as actually misleading), 

 shales, some with and some without nodules of ironstone, cal- 

 careous and non-calcareous limestone in beds rarely exceeding 

 twenty feet, coals usually not thick, but not very inferior in 

 quality to those in the coal-measures proper, and underclays. 

 The general nature of these beds has been described over and 

 over again, in the most accurate manner, in the Transactions of 

 this Club, by the late Mr George Tate, F.G.S. , and need not be 

 repeated here. The term Bernician, however, is somewhat new 

 in its present application, (4) and it may be well to remind the 

 reader that the Upper Bernician is in a general way (that is 

 without a hard and fast line of division, either above or below), 

 the representative of the Yoredale Eocks, (5) and the Lower Ber- 



(2) Lebour's " Outlines of the Geology of Northumberland," p. 15. 



(3) See "Transactions of the North of England Institute of Mining and 

 Mechanical Engineers," Vol. xxv. (1875-76). 



(4) See " Geological Magazine" Decade ii., Vol. iv. (1877). 

 (6) Ibid., Decade ii., Vol. ii. (1875), p. 539. 



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