12 MR. J. E. MAKE ON THE TARNS OF LAKELAND. [Feb. 1 896, 



2. Additional Notes on the Tarns of Lakeland. By J. E. Marr, 

 Esq., M.A., E.R.S., Sec.G.S. (Read November 20th, 1895.) 



The following notes form a supplement to a paper on ' The Tarns 

 of Lakeland' read before the Society in 1894. 1 I have had the 

 opportunity during the present summer of devoting more time to 

 the study of Watendlath Tarn, and have examined three other tarns 

 of some interest. 



(a) Watendlath Tarn. 



In my former paper, I stated that in the case of Watendlath 

 Tarn * a great mass of drift is plastered against the east side of the 

 valley, and may have filled the old valley.' I have since ascer- 

 tained that there is no old valley there, but that the solid rock runs 

 all round the northern, eastern, and southern ends of the tarn : 

 I furthermore stated that ' on mounting some way above the tarn 

 I saw indications of the possible existence of a moraine-filled 

 depression ' on the western side. I have now examined this de- 

 pression and satisfied myself that beneath it lies buried the old 

 valley, the stream from which ran down into Borrowdale near Ros- 

 thwaite — that is, about 3 miles south of the present junction of the 

 Watendlath valley with Rosthwaite, near Lowdore. This moraine- 

 filled depression runs close to the path from Rosthwaite to Watendlath 

 Tarn. The watershed here is about 200 feet above the surface of 

 the tarn, and, as the tarn is 46 feet deep, it requires a barrier of 

 drift over 250 feet in thickness to account for the tarn ; but, as the 

 valley is evidently a narrow one, and its course lay at right angles 

 to the direction of the ice, the occurrence of this somewhat thick 

 mass of drift presents no difficulty, and a much thicker mass has 

 been recorded in the neighbourhood filling up an old valley, as proved 

 by boring in Furness. 



Proceeding from Rosthwaite towards the tarn, the path ascends 

 by the side of a stream running from Brund Pell to a spot called 

 Birkett's Leap, where it leaves the main stream and is carried 

 parallel with a tributary descending from the lowest part of the 

 watershed. The stream from Brund Fell and the lower part of the 

 tributary stream have cut to a considerable depth between rock and 

 drift, the northern bank of the stream being composed of ruck, and 

 the southern side of drift, so that the streams appear to be gradually 

 cutting out the old valley (see fig. 1). To the east of Birkett's Leap, 



1 Quart. Journ. Geol. Soc. vol. li. (1895) p. 35. In this paper the following 



errata occur :- 



Page 39, last line, for ' Ask ' read ' Ark.' 

 „ 42, line 7 from bottom, for ' lower ' read ' southern.' 

 „ 42, line 8 from bottom, for ' upper ' read ' northern; 

 „ 44, line 7 from top, for ' east ' read * west.' 

 „ 45, line 5 from bottom, for ' east ' read ' west.' 



