210 



THE GEOLOGIST. 



hills, so to speak, is N.W. and S.E., with a narrow vale or channel 

 lying between, the striae will be found having the same undeviating 

 direction right across from N.E. by N. to S.W. by S. This is 

 exemplified in the hills bordering the vale of Newland, near Ulver- 

 stone, where a brook now runs from 300 to 400 feet below the heights 

 on each side. There is no question, however, but that the gill is 

 deeper than when the ice crossed it, but the striation is repeated on 

 the N.E. side down to 275 feet from the top, and at rather more than 

 125 IVet above the brook ; while it is a curious fact that this happens 

 to be about the elevation above the brook, of the lowest obtained 

 striae on the S.W. side. 



At the same time, although this is very likely to be the prevail- 

 ing tendency of striae in Furness, yet there are exceptions, and a 

 slight deviation will sometimes occur between two points within a 

 short distance of each other. Thus, on Grameswell Hill, deep 

 groovings pass from N.N.E. to S.S.W., while rather more than half 

 a mile off the striation is from E.N.E. to W.S.W. Yet neither of 

 the two striations can have any connection with the present features 

 of the locality. The gill that passes under Gameswell on the west 

 cuts directly N. and 8.,, and the rocks w T ith the latter striation are on 

 the south-eastern slope of a fell, down which small drainage depres- 

 sions pass to the E. and S.E. 



lc should be conceded, I think, to the inexperienced student, that 

 there n ay be great difficulty sometimes in selecting glacial striae out 

 of "weathered " lines of cleavage and stratification in the slate rocks. 

 The difficulty is not when they present their edges sharp, close, and 

 regular ; but when e.g. somewhat resembling the spreading leaves of 

 an opened book, they have been further worn into horizontal hollows, 

 ruts, or grooves ; and this, possibly, by the glacier passing over at 

 right angles to them, rather than parallel w T ith them, as would be at 

 first suggested. The above is only one out of other instances of de- 

 ception met with on decomposing slate rocks. It must occasionally 

 happ n that true striae may run parallel with either the cleavage or 

 bedding ; but in these doubtful cases I have uniformly abandoned 

 them, and it is m,% unlikely that g >od genuine striae, which the ex- 

 perienced geologist would have noted down, may thus have escaped. 



On the craggy heights of the moors, as well as in some places on 

 the shore, the aspect of the rocks indicate that the principal denuding 

 force has been carried ov er from the north. They generally present 

 their smoothed sides to the north or north-east, their rugged ones to 

 the opposite point: deep ruts passing up the smooth incline answer- 

 ing in point of depth to the opposition that incline had presented. 

 In some instances the edges of the cleavage planes have been so 

 shaved <ff. grooved across at right angles, and rounded, as strikingly 

 to resemble the laminated structure of a shell-hill contour. 



With regard to the form and outline of many of our hills, the 

 beautiful description given at some length by Mr. Q-eikie, of the 

 glaciation among the mountains of Scotland, might well serve for a 



