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The authors first briefly describe the general relations of the zone 

 of carboniferous limestone (surrounding the primary Cumbrian system) 

 to the central carboniferous chain, and show that this zone has been 

 separated from the central chain by a great downcast fault, described 

 in a preceding memoir. In illustration of this, Ihey give a transverse 

 section from the carboniferous limestone ridge, south of the river 

 Lowther, to the chain of Cross Fell, proving that this low limestone 

 ridge is not connected with the elevated chain, but with some dislo- 

 cated masses which appear at its base, and dip towards the valley of 

 the Eden. 



They then give a detailed account of the range of the carboniferous 

 limestone from the neighbourhood of Kirkby Stephen to Egremont. 

 Beyond the latter place, patches of limestone are also staled to occur 

 at Mousehole, Kirksancton, and Hodbarrow-Point, giving indications 

 of at least a partial extension of the carboniferous series along the 

 S.W. coast of Cumberland. Lastly, they notice the prolongation of 

 the limestone (chiefly in great detached tabular masses) through Low 

 Furness and a part of Westmoreland, till the broken zone reaches the 

 great downcast fault at the base of Ingleborough. 



They afterwards describe, in considerable detail, the sections ex- 

 hibited by the carboniferous zone between Kirkby Stephen and Egre- 

 mont, It is stated that the lower part of the carboniferous limestone 

 corresponds, on the whole, with the great scar limestone of Yorkshire; 

 but it is, here and there, more subdivided by thin beds of shale and by 

 coarse beds of sandstone. Near Hesket Newmarket two or three beds 

 of coal (some of which have been considerably worked) appear in the 

 lower part of the series, offering an analogy to the structure of the 

 central carboniferous chain on its approaching the Scotch frontier. 

 They are stated to thin off in the lange towards the west, and the 

 formation to resume its more ordinary characters. The authors then 

 give a section from the rivulet below Cieator through Bigrigg-moor, 

 by which they show, (1.) that the limestone series is there greatly di- 

 minished in its aggregate thickness ; (2.) that it contains subordinate 

 irregular beds of red haematite (now extensively worked) ; (3.) that it 

 is separated from the new red sandstone by thin bands of magnesian 

 conglomerate. 



They afterwards describe several sections in an upper division of 

 the series, intermediate between the great scar limestone and millstone 

 grit. The principal details are derived from the Westmoreland range 

 of the limestone, and from the works in the neighbourhood of Cald- 

 beck Fells. In these localities thin beds of coal alternate with the 

 shale and limestone, and have been worked to a considerable extent. 



The millstone grit is ill exhibited along the line of range; but may 

 in some places be concealed under the great accumulation of alluvial 

 matter on the confines of the new red sandstone. The great upper 

 coal formation commences near Rosley, and is greatly expanded in 

 its extension towards the west, so as to occupy the whole coast from 

 St. Bee's Head to Maryport, But all details respecting it are referred 

 to a subsequent communication. 



In the concluding portions of the paper the authors briefly notice 



