590 



J. E. MAER AND ME. W. G. EEARNSIDES ON [Nov. 1909, 



minor streams rose somewhat to the north of the main watershedding 

 line, but the streams of Uldale, Langdale, Bowderdale, and Artle- 

 garthdale all rose upon that line. Owing to the gentleness of the 

 slope all these streams had low grades. South of the main water- 

 shedding line, on the short scarp-slope, brief steep-graded streams 

 flowed southwards to the Rawthey, namely, Hobdale, Cautley, 

 Backside, and "Wandale Becks ; and the steep side towards the Lune 

 south of Tebay was also drained by the short and steep Carling Gill 

 and Blands Gill and their tributaries. 



The early dissection of the monoclinal block-tract was produced 

 by these streams and their tributaries ; but, as the northward flowing 

 streams are near together, their tributaries are unimportant, and 



hence the ancient 



Fig.l. — Plan illustrating the drainage of Backside surface of the Silu- 



and Wandale Becks and Artlegar'thdale. rian platform is 



■ preserved on the 

 divides between the 

 streams with but 

 little change. 



Modifications of 

 the drainage are 

 due to the ten- 

 dency of the short 

 swift streams flow- 

 ing to the Lune 

 south of Tebay and 

 to the Rawthey on 

 the south of the 

 fells to cut back 

 into the watershed, 

 and to capture the 

 head waters of the 

 northward - flowing 

 streams. 



Beginning at the 

 north - west, and 

 working south - 

 wards and then 

 eastwards, we find 

 that the first important captures are made by Carling Gill. The 

 head of Tebay Gill remains intact ; but that of Ellergill next to the 

 east has been cut off, and a col connects it with Carling Gill. The 

 most striking capture, however, by Carling Gill is that of the Black 

 Force stream and of the head of Uldale. Farther south another 

 of the westward-flowing streams, Longrigg Beck, has cut off the 

 heads of two of the tributary streams of another Ellergill, which 

 flows to the Lune. A feeder of Longrigg Beck has also beheaded 

 West Grain Beck, a tributary of the northward-flowing Langdale 

 Beck, and has so produced the col known as Wind Scarth Wyke. 



Scale: 

 ?4 inch= 



[The dotted line indicates the direction of the former 

 drainage.] 



