86 



Beck and Carwinley Burn. A farm called Grainhead stands on the 

 north side of the Burn, above Prior Rigg and Hethergrove,and below 

 Fieldhead. The unconformity may be seen in the stream where 

 it bounds the field south-east of the Grainhead farm buildings, and 

 is a little above the bridge. There is breccia at the Permian base, 

 and the brick-red beds are seen to rest on Carboniferous rocks of 

 various colours, which dip at a much higher angle. 



In this, which may be called the Border district, misapprehension 

 as to the true affinities of the various red or reddish-tinted rocks 

 has led, as in the Wigton district, to an undue enlargement of the 

 Permian boundary. This may be seen on comparing the map 

 attached to Mr. Gibsone's paper on the Border districts of Cum- 

 berland* with the remarks I have made as to the real amount of 

 Permian ground on the Esk and Liddel. Thus : in Mr. Gibsone's 

 map the Permian boundary line crosses the Esk about three-quarters 

 of a mile north of Canobie church. But, as I have already 

 remarked, the church stands on Carboniferous rock, the boundary 

 crossing the river at least half a mile south of the church. Again, 

 on the Liddel, Mr. Gibsone places the boundary line a mile and a 

 half, or thereabouts, higher up the stream than the presence of 

 brick-red rocks would justify him in doing. But in the Wigton 

 district so much larger is the amount of territory improperly 

 annexed to the Permian formation than on the Border, that the 

 importance of the true colour-test near Wigton is worth showing 

 by means of a sketch map illustrating the older and the newer 

 views. For this purpose I give the boundaries of the Carboniferous 

 and Permian rocks south of Wigton, as they appear in the sketch 

 map appended to Matthias Dunn's paper, and also as they are 

 drawn in that illustrating my paper on the Carlisle Basin, already 

 referred to. 



I trust, in conclusion, that sufficient evidence has been given to 

 prove my case that brick-red is the characteristic Permian red, and 

 that purple-grey and pinkish rocks, being invariably found to be 

 Carboniferous where there is plenty of evidence besides that of 

 colour, may fairly be presumed to be Carboniferous where colour 

 * North Eng. Inst. Min. Eng., vol. xi. 



