Vol. 65.] THE HOWGILL FELLS AND THEIK TOPOGRAPHY. 593 



(A) Glaciatioii of the Lowland Tracts around the 

 Howgill Triangle. 



(1) The Eavenstonedale Lowland. — Examination of Good- 

 child's map in the paper cited shows the line of the approximate 

 southern limit of the Shap Granite boulders and the eastward trend 

 of the ice which carried them. There is little doubt that these 

 boulders were kept from passing southwards by the Howgill ice 

 which was emerging from Langdale and the valleys on the east, 

 which, as far as Artlegarthdale, are filled with drift charged with 

 Howgill boulders. But Tebay Gill is filled to the head with drift 

 from the north, containing boulders of Carboniferous rock, Shap 

 apophyses, and occasional boulders of the parent Shap Granite. (One 

 actual fragment of the last-named, an inch and a half in diameter, 

 was taken from a clay-bank near the head of Tebay Gill ; and 

 a large mass, 6 feet in diameter, may be seen close to the mica-trap, 

 half a mile east of Tebay railway-station, in the stream, and many 

 others of less notable size abound in the same neighbourhood.) 

 A thermally metamorphosed mass of Tarlside rhyolite was also 

 observed. Ellergill has Carboniferous boulders a long way from 

 its mouth, and possibly all the way to its head. It will be noticed 

 that both Ellergill and Tebay Gill are short and comparatively 

 unimportant valleys, which start far north of the main water- 

 shedding line of the Eells. 



The ice which filled the Eavenstonedale depression was respon- 

 sible for the formation of the gorge through which the Sinardale 

 stream flows : the Smardale Gorge is, in fact, a marginal overflow. 

 (In a paper published in the Proceedings of the Geologists' 

 Association, vol. xx, 1907, p. 147, one of us did not accept the 

 idea of a marginal overflow from ice, but during a subsequent 

 visit was convinced by Prof. "W. M. Davis.) A similar overflow 

 occurred in a tributary valley from Sunbiggin Tarn, and another to 

 the east of Ashfell Edge ; but these have not produced any marked 

 deflection of the drainage. We are not, however, concerned with 

 marginal overflows in the present paper. 



(2) The Lune-Gorge Lowland. — That ice from the Lake 

 District flowed some way down the Lune gorge is shown by the 

 fact that boulders of Shap Granite and apophyses have been noted 

 by Prof. Hughes at the foot of Carling Gill, and boulders of the 

 apophyses have been found by us as far as Lincoln's Inn Bridge. 

 A boulder of the granite was also noted at the bridge, but may have 

 been carried down by the stream. The scarcity of these boulders 

 shows, however, that the Lune ice was diverted south-westwards, as 

 maintained by Mr. Dakyns and in the Geological Survey Memoir. 1 

 That the ice coming from the Howgill Eells (especially through the 



1 ' The Geology of the Country around Kendal, Sedbergh, Bowness, & Tebay ' 

 Mem. Geol. Surv. 1888, p. 49. 



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