1856.] HARKNESS PERMIAN ROCKS OF SCOTLAND. 255 



Topography of the Sandstone areas. — To commence with the 

 eastern side of the county, we have, occupying the S.E. extremity, a 

 portion of the great deposit of sandstone which covers so large a sur- 

 face of Cumberland. This has the usual aspect of the deposits in the 

 latter county ; and, if we regard the sandstone of the country around 

 Carlisle as Triassic, we have no alternative but to adopt the same 

 nomenclature for this portion of the Dumfriesshire sandstones. 



This area, commencing on the Solway Frith, in the parish of Cum- 

 mertrees, and running in an E.N. E direction to the Liddle at Can- 

 nobie, I regard as Trias, and newer than the deposits to be more fully 

 alluded to. 



In the Vale of the Annan, about six miles to the north of the above- 

 mentioned area, the country is occupied by another area of sandstone, 

 to which the name of the " Corncockle area" may be applied. Whe- 

 ther this can be connected with the deposits which occur on the east 

 side of the River Annan, to the south and north of Moffat, is doubt- 

 ful ; and I am at present disposed to consider that in the higher por- 

 tion of the Vale of the Annan there are three distinct areas, viz. the 

 Corncockle, — the one which is seen in the form of a breccia in the 

 streams immediately to the E. of Moffat, and to the S.E. at Bellcraig 

 Linn, in the state of both sandstone and breccia, — and the third, filling 

 up the head of the Annan in the district called the "Marquis of 

 Annandale's Beef-tub." 



To the N.W. of the north-western extremity of the Corncockle 

 area, beyond several ridges of Lower Silurian mountains, there is 

 found another spot where the sandstone presents itself, viz. to the 

 S. of the farmhouse of Mitchell-Slack, in the course of the Capple 

 Water. The area occupied by this is very small, probably not ex- 

 ceeding half a mile, if so much, in diameter ; and the beds here have 

 a brecciated character. 



Westward from this last, we have another patch, of considerable 

 size, occupying the east side of the Nith, from the Drumlanrig tunnel 

 on the Glasgow and South-western Railway, to near Blackwood, 

 having more than six miles in a N. and S. direction ; and exceeding 

 two miles in its greatest breadth. 



To the south of this the " Dumfries area" appears, which has 

 been already described. If the higher portion of the Vale of the 

 Annan contains three areas of sandstone, we have scattered over the 

 face of Dumfriesshire seven distinct patches of this substance ; and 

 these areas are well and widely separated from each other. If the 

 higher portion of the Vale of the Annan contains only one patch, 

 then we have five areas occurring under like circumstances. 



Each of these several areas, with the exception of the one regarded 

 as Trias, and the one which appears in the course of the Glasgow 

 and South-western Railway immediately south of the tunnel (which 

 may be termed the "Thornhill area"), has so far as can be deter- 

 mined Lower Silurian rocks for its margin. The other two are sur- 

 rounded by Carboniferous rocks. 



Sandstones and breccias of an age posterior to the Carboniferous 

 are not confined in the South of Scotland to Dumfriesshire; we 



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