Drift. i?=Rock. 



Vol. 52.] MR. J. E. MARK ON THE TARNS OF LAKELAND. 13 



the tributary crosses to the southern side of the drift-filled depression, 

 and east of this the rock lies on the southern, the drift on the northern 

 bank. At the top of the pass, the path is on the northern border of 

 the drift-filled depression, which is readily traceable towards the tarn. 

 Some way below the top of the pass on the Watendlath side, a stream 

 called Bowdergate Gill runs along the depression, and has cut a 

 ravine in it, which is well wooded towards the tarn. In some places 

 this ravine is about 

 50 feet deep, and is cut 

 entirely through drift, 

 with drift forming the 

 bed of the stream. 



It may be noted that 

 on looking towards the 

 eastern side of Borrow- 

 dale from below Ros- 

 thwaite, the col above- 

 mentioned is the only 

 place where solid rock is 

 not visible against the 

 sky-line for a distance of about 2 miles, and it is also the lowest 

 portion of the sky-line in this space. 



There are indications of an old terrace some way above the 

 present surface of the tarn, which are most clearly seen on the 

 eastern and southern sides. This probably marks the original 

 height of the old col between the former Watendlath and Lowdore 

 valleys, which would form the exit of the lake after the stoppage of 

 the narrow Watendlath-Hostkwaite gorge, the rocky ravine just below 

 the tarn having since been deepened to the extent indicated by the 

 difference of level between the present surface of the tarn and the 

 summit of the old terrace. 



{b) Hard Tarn, Helvellyn. 



In his paper on * The Glaciation of the Southern Part of the 

 Lake-District and the Glacial Origin of the Lake Basins of Cumber- 

 land and Westmoreland,' l Clifton Ward remarks (p. 161) : — ' Just 

 below and south of Nethermost Pike, Helvellyn, in Euthwaite Cove, 

 is Hard Tarn, 150 feet by less than 100 in size ; it is very shallow, 

 so that one can see the rocky nature of its bed and sides, and mark 

 how the ice-scratches pass beneath the water from one side to the 

 other.' Owing to the above statement and to the small size of the 

 tarn, which might well be a rock-basin, even if the other tarns of 

 the district are only drift-dammed, I was particularly anxious to 

 see this lakelet, but was prevented by bad weather in former years. 

 This year I had an opportunity of examining it. The pond lies on 

 a dip-slope of some ash-beds having a gentle inclination towards a 

 steep escarpment-cliff above, which is surmounted by another dip- 



1 Quart. Journ. Geol. Soc. vol. xxxi. (1875) p. 152. 



