1872.] 



TIDBEMAN- ICE-SHFET EST NOETH LANCASHIRE ETC. 



479 



Clitheroe Distnct. — These last have a general agreement with a 

 scratched " roche moutonnee" on Twiston Moor, on the north-easterly 

 extension of the ridge which culminates in Pendle Hill. It is a com- 

 plete parallel to those on Bowland Knotts before mentioned ; for the 

 scratches are running across the range and not from the summit of 

 Pendle, the highest ground in the neighbourhood. Also the scratches 

 here and those on Bowland Knotts are almost in the same straight 

 line. A proof will be given under the next head that these scratches 

 were formed by ice coming from the north rather than from the south. 



In the gorge of the Calder, which cuts across the Pendle range at 

 Whalley, is a very fine large " roche moutonnee " well scratched. It 

 shows pretty clearly by its form that the ice was going up the course 

 of the present river (or southward), not down it (or northward) . This 

 rock, as shown by the drift sections on both sides of the ravine, was 

 well covered uj) by a good thicknesss of Till, and above that again by 

 forty feet of the "middle sands and gravel;" so that it must have 

 been worked by the ice of the land-ice period, not by icebergs, coast- 

 ice, or ice-foot — nor yet by later glaciers ; for in that case those later 

 deposits would have been ploughed out. It will be seen, if we put 

 together the scratches in the neighbourhood of Pendle, that to the 

 north of it they appear to be deflected by that eminence, and that to 

 the south they would seem to be coalescing again. I can conceive 

 its being quite possible that the ice-sheet went quite over Pendle ; 

 but even then the base of the ice-stream would be influenced in its 

 course by the slopes of the ground, and some such ett'ect as that 

 noticed would be produced. 



Close to the south bank of the Eibble, at the junction of Starling 

 Brook, about two miles above Ribchester, are some scratches trending 



Fig. 1. — Diagram sJwiving the proportion of Ice-scratches running in 



different directions in North Lancashire Sfc. 

 W. E- 



S. 8° W., whereas the valley is running W.S.W. I do not think 

 these can be referred to later glaciers ; they would rather seem to 



