Vol. 65.] IN THE NEIGHBOURHOOD OE ESKDALE. 57 



in the small gorge at the head of the cascade, about 10 yards below 

 the point where a small tributary joins the stream on its left bank. 

 Close to the junction the granite is white with a greenish tinge, is 

 extremely fine-grained, and contains 96-16 per cent, of silica. 

 Some 10 yards farther from the margin it assumes a pink colour, 

 and is similar in texture to the finer specimens from Robin Gill. 

 Specimens of the actual junction were collected, and a junction- 

 breccia, consisting of fragments of Borrowdale lava in a granite- 

 matrix, occurred as boulders in the bed of the stream. 



In Oliver Gill the junction occurs at about 1150 feet, the actual 

 contact being obscured by boulders. The granite and the Borrowdale 

 rocks may, however, be traced to within 15 yards of each other, the 

 former showing marginal features. From Oliver Gill the boundary 

 rises considerably, and on Blaebury How is at a height of 1350 feet. 

 The granite is fine-grained and white ; the fine-grained pink variety 

 comes in farther from the margin and extends down to 1150 feet, 

 gradually passing into the normal granite at lower levels. 



The edge of the granite now passes along the flanks of Great 

 How and gradually assumes a lower level, until at Whinscales 

 Sheepfold, near the head of Brockshaw Beck, it is at a height of 

 1200 feet. At this point the junction dips at an angle of about 

 45° eastwards. The marginal zone is unusually narrow at this 

 point, the rock in contact with the granite being a bedded ash. 

 There is a well-marked junction -breccia here, the fragments of 

 Borrowdale Ash between the granite-veins being remarkably 

 angular and showing no signs of absorption (100 & 101). 1 



Stony Tarn lies in a hollow in the Borrowdale rocks, the granite- 

 boundary sweeping round to the south-west of it, and being cut 

 off by a fault at Peelplace Noddle. Between Peelplace Noddle and 

 the River Esk the country is much faulted, the faults carrying 

 some haematite, being marked on the Survey-maps as metalliferous 

 veins, and rendering the boundary somewhat intricate. 



The most noteworthy features in this area are the j unction - 

 breccia, which is developed on a large scale near Whin Crag (131 & 

 132), and the junction near the confluence of Scale Gill with the Esk. 

 At the latter place the granite is somewhat coarse to within a few 

 feet of the margin, and consists of quartz and felspar, the quartz- 

 masses in some cases attaining several inches in diameter. Close 

 to the margin it becomes finer in texture, and is bounded by a layer 

 of almost pure quartz (108J : this is in contact with the Borrowdales, 

 which are much altered (see p. 68). The junction dips at a high 

 though variable angle south-eastwards. 



The boundary passes thence by Whahouse Bridge, and crosses to 

 the southern (left) bank of the Esk, but is not well seen until Force 

 Gill is reached, where it is at 450 feet above sea-level, thus having 

 fallen some 900 feet from its highest point on Blaeberry How. 



1 These numerals within parentheses indicate, throughout the paper, the 

 numbers of the localities on the Author's MS. maps and of the corresponding 

 rock-specimens and microscopic slides, all deposited in the Museum of the 

 Geological Department of the University of Leeds. 



