430 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 23, 



what is already known, are merely intended to stimulate to further 

 research*. 



8. Connexion between Boulder-drifts and Superficial 

 Accumulations at high Leyels. 



I have not seen any Lower Boulder- clay or pinel in the Eumess 

 peninsula at a higher level than nearly 800 feet above the sea (between 

 Ulverstone and Beckside). In the valleys and on the slopes of the 

 Coniston Old Man, I have traced it up to about 900 feet near Paddy- 

 End Copper Works, and to about 1200 feet on the Walna Sear road 

 and between it and Goat's Water. The Upper Boulder-clay of Fur- 

 ness may be traced up to at least 700 feet (above Soutergate). On 

 the Old Man I have traced a coarse rubbly clay overlying either 

 pinel or sand and gravel up to at least 1200 feet above the sea. 

 On the same mountain, rounded gravel may be found up to 1000 

 feett- In south Lancashire Mr. Hull has not been able to trace the 

 undoubted Lower Boulder-clay up to any considerable height. The 

 middle drift rises higher J, and the Upper Boulder-clay higher still, 

 while erratics may be found on the Pennine hills up to 1800 feet, 

 proving a submergence of north-central England to that extent §. 

 I believe I saw a patch of erratic Upper Boulder-clay, at least 1000 

 feet above the sea, at the entrance of the railway tunnel north of 

 Dove Holes (near Buxton), Derbyshire. But from an examination 

 of the extent to which drift deposits, with erratic stones, graduate 

 upwards into deposits with angular stones of local derivation, and 

 from a comparison of the superficial accumulations at low and high 

 levels in Lancashire and Derbyshire, I have been led to the follow- 

 ing conclusions : — 



(1) During the period of the great north and south flow of land- 

 ice, superficial detritus, either loose or closely packed, was left in 

 hollows or on the lee side of rocky projections and knolls ; but no 

 extensive and continuous spread of Boulder-clay resulted from its 

 action. 



(2) During the succeeding submergence the sea rearranged the 

 previously existing surface-detritus, and combined with land-ice in 

 giving rise to a variety of superficial phenomena of denudation and 

 deposiiion, which will require much research to decipher. 



(3) The principal part of what are called drift deposits was de- 

 rived from the waste of local rock formations, and accumulated by 

 the ordinary action of the sea. In most places, especially at a dis- 

 tance from hills, comparatively little of the finer part of drift deposits 



* The Eev. Mr. Thornber informed me that Connemara Marble (?) had been 

 foimd in the Boulder-clay at Blackpool ; and a workman once showed me a 

 specimen of Gryphma incurva he had picked up on the beach. The latter may 

 possibly have been brought to Blackpool as ballast in a vessel. 



t For an account of the drifts of the Old Man see ' Scenery of England and 

 Wales,' by the author of this paper. 



X It is well known that shell-bearing middle drift has been found in the 

 neighbourhood of Macclesfield, and on the Macclesfield and Buxton road, up to 

 1200 feet above the sea. 



§ Mem. Lit. and Phil. Soc. Manchester, vol. ii. 3rd series. 



