598 BE. J. E. MAKE AND MR. W. G. EEABNSIDES ON [jSibv. I9O9, 



successive diversion by delta -growth of the downward tributaries 

 of beheaded streams (however beheaded) must be a common 

 feature, and we shall deal with another case in our district. 



Cases of these delta-watersheds are described under the name of 

 ' corroms ' by Prof. P. F. Kendall & Mr. E. B. Bailey in tbeir account 

 of ' The Glaciation of East Lothian South of the Garleton Hills.' J 



Eig. 3. — The corrom : Blalceiliwaite Bottom, looking east. 



[The stream to the south of the corrom flows into the Spout.] 



The old head of the valley below TTlgill Bigg is well glaciated, 

 there being a Glacial combe there. Some of the ice possibly went 

 over the col between Bleagill Head and Taffergill into the combe at 

 the head of Churn Gill ; but the main part went down the old 

 Uldale Valley, though apparently it produced but little erosive 

 effect, except in the combe at its head, depositing, however, a con- 

 siderable amount of drift in the valley. 



The lower part of Uldale, discharging northwards, will be 

 described in its proper place. 



South of Carling Gill is Eair Mile Beck, rising in two 

 tributaries on the west side of Eell Head. The valley is a 

 U-shaped valley, and its tributaries are also U-shaped, a small 

 corrie-moraine occurring at the base of a small combe at the head 



1 Trans. Boy. Soc. Edin. vol. xlvi (1907-1908) p. 25. 



