302 J. E. Marr— Studies in Lal-eJand. 



At the northern end of the old lake, the Caldevv cuts through a 

 narrow gorge hollowed out of the Eycott volcanic rocks to a depth 

 of about twenty feet.i The top of this gorge is somewhat lower than 

 the top of the drift bar at the south end of the old lake. 



It seems clear that in pre-GIacial times a low watershed, between 

 ■what are now the upper waters of the Caldew and the present lower 

 (and principal) part of the river, existed at Linewath, and that the 

 present upper waters of the Caldew then drained into the Glendera- 

 mackin; that during the Glacial period the terminal moraine of the 

 Helvellyn ice-lobe blocked the present upper part of the Caldew, 

 separating it from the Glenderaraackin and forming the lake, and 

 that this lake has been destroyed, partly by silting up and giving 

 rise to Mosedale,^ Bowscale, and White Mosses on its site, and 

 partly by the cutting down of the stream at the outlet of the lake, 

 forming the little gorge at Linewath. The diversion of the river 

 would add an additional ten miles to the length of the Caldew. 



(c) Minor Moraines in the GlenderamacTcin Drainage Area. 



At the south end of Bannerdale Crags, and almost half-a-mile 

 south-east of Bannerdale lead mine, a small ci'escentic moraine 

 occurs at the bottom of a " comb." A stream section shows the 

 moraine-stuff to consist of gravelly clay, with numerous subangular 

 striated blocks of Skiddaw Slate. A similar moraine is seen at the 

 foot of Scales Tarn (ST). The stream from the tarn has cut a 

 section in a very stiff clay with many scratched boulders of Skiddaw 

 Slate. It is clear that this moraine has caused the formation of 

 Scales Tarn, which is neither a rock basin nor due to blocking by 

 snow-slope screes. At the time of my visit this year, on April 7th, 

 the tarn was still frozen over. 



A very pretty crescentic moraine noticed by Clifton Ward occurs 

 beneath Wolf Crags (W) at the north end of the Helvellyn Range. 

 It is known as Barberry Rigg, and its two ends are a little more 

 than half-a-mile apart in a straight line.- In places it is about 

 40 feet high, and must at one time have given rise to a tarn, now 

 occupied by a peat moss. A gorge about 30 feet deep, cut through 

 it, shows that it is a true moraine, in which a few scratched stones 

 occur amongst the subangular blocks which fill it, though, owing to 

 the nature of the rocks, one cannot expect many scratches to be 

 preserved. Before the formation of the gorge the tarn must have 

 been over 20 feet deep, and probably considerably deeper, as a good 

 deal of deposit has taken place in it. Mr. Clifton Ward alludes to it 

 in the Geological Survey Memoir " On the Northern part of the 

 English Lake District," pp. 90 and 98. He remarks, on p. 98, that 

 " the glaciers crept down to the level of the sea, sometimes forming 

 moraines just at the sea-margin, as was the case beneath Wolf Crag, 

 Matterdale Common, when the land stood 1,400 feet below its 

 present level." He gives no reasons for the view that this moraine 

 was formed at the sea-level, and though I devoted a considerable 



1 Yet another Mosedale. 



^ See 6-inch map, geologically coloured. 



