Vol. 62.] ANNIYEESARY ADDBESS OF THE PRESIDENT. CV 



shatter-belts in which the geological structure of the shattered 

 rock is seen, occur on mountain-sides. I may mention as examples 

 Tilberthwaite Gill, in the Coniston Pells, of which the upper part 

 has been excavated owing to glacial diversion ; the streams on 

 either side of Wrynose and Hardknott Passes, occupying parts of 

 a great belt the trend of which has been previously noted ; the 

 stream behind the cottage at Blea Tarn, Little Langdale ; that of 

 Rossett Gill, of Ruddy Gill, of the stream entering Sty-Head Tarn, 

 and of Aaron Slack, occupying parts of another of the great belts ; 

 Peers Gill on Lingmell ; and those which course down the hill to 

 the east of Watendlath Tarn. Some of these have already been 

 noticed ; they are but samples of hundreds scattered through the 

 district. 



In the larger valleys, save where glacial diversion has occurred, 

 as above described, it is usually difficult to obtain direct evidence 

 of the existence of shatter-belts, owing to the covering of alluvium 

 which at present exists along considerable portions of their courses. 

 In many cases, however, the shatter-belts which are seen on cols, 

 and down the slopes, if continued along the main valleys, would 

 run along the portions of those valleys that are marked by their 

 straightness, and may often be traced up another hillside at the 

 farther end of such a straight portion. Let us take some instances. 



The shatter-belt seen on either side of the col of Dunmail Raise 

 runs in a direction marked by the straight portion of the Thirl- 

 mere valley on the north and of the Vale of Grasmere on the south. 

 Each of these valleys when leaving this belt loses this straightness, 

 the Thirlmere valley where the river passes into the Yale of 

 St. John (probably owing to glacial diversion), and the Grasmere 

 Valley where the stream flows from Grasmere to Rydal (perhaps 

 owing to capture of the stream, which once continued along the 

 shatter-belt to Elterwater, by a strike-stream working back along 

 the softer rock of the slate-band between Ambleside and Rydal). 



In Great Langdale, the valley below the Dungeon-Gill Hotels 

 is formed by the coalescence of two upland valleys : Oxendale, 

 which is continuous with Crinkle Gill, worked along a shatter-belt 

 on the side of Crinkle Crags, and Mickleden which is worked along 

 one of the three great shatter-belts previously noted. On the line 

 of Mickleden at its upper end this belt is seen in Rossett Gill, and 

 at the lower end it leaves the valley and crosses the col between 

 Great and Little Langdales. 



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