65 



In some cases the line of separation between the Lower Boulder 

 Clay and the Middle Sands and Gravels is somewhat indistinct, 

 and the two beds are partly mixed together, as shewn in Fig. 5, 

 which represents a section seen near Branthwaite edge, on the 

 Ullock and Parton Branch of the London and North Western 

 Railway. The transition from the Boulder Clay (C) to the upper- 

 most bed of coarse gravel and boulders (B) was in some parts of 

 this section so very gradual that it was impossible to say where 

 one ended and the other began. 



Imperfections, such as the above, in the tripartite arrangement 

 of the deposits, I have found most frequently on the sides of valleys 

 or on the ridge separating two valleys. Thus, from the bottom of 

 a valley where the whole three members of the series are present, 

 we may frequently, on passing up the sides of that valley, see the 

 upper clay disappear altogether, and the Middle Sands and Gravels 

 come out at the surface. Farther up again the Lower Boulder 

 Clay may be next the surface — the Middle Sands and Gravels, as 

 well as the Upper Boulder Clay, having disappeared. 



The Middle Sands and Gravel, where they present any appear- 

 ance of bedding, are often curiously contorted, both when they lie 

 next the surface and when they are covered by the Upper Boulder 

 Clay. 



It has been already mentioned that the ridges separating valleys 

 on the lower ground are often capped by either St. Bees Sandstone, 

 Permian Breccia, or Whitehaven Sandstone. When this is the 

 case, the superimposed glacial deposits are, as a rule, extremely 

 scanty, seldom exceeding five or six feet in thickness, and, so far 

 as my experience goes, they are undivided ; that is to say, they 

 are not split up like the deposits shewn in Figs, i, 2, 3, into 

 different layers, but occur as one layer only. Whether this single 

 undivided layer, which usually presents the general characters of 

 boulder clay, is the equivalent of the Upper- or of the Lower 

 boulder clay, or of both, as they occur in the valleys, I have not 

 been able to determine by observation. 



In many cases the deposits are accumulated mainly on one side 

 of a valley, as shewn in Fig. 6, which is a section taken through 



5 



