1869.] 



MACKINTOSH LANCASHIRE AND CUMBERLAND DRIFTS. 



407 



6. On the Correlation, Nature, «nf? Origin of the Drifts o/ North- 

 west Lancashire and a part of Cumberland, with Eemarks on 

 Denudation. By D. Mackintosh, Esq., F.G.S. 



Contents. 



1. Introduction. 



2. Coast-section of Drifts at Blackpool. 



a. Uppfer Botilder-clay. 



b. Middle Sand and Gravel. 



c. Eagberg " Rockery." 



d. Lower Boulder-clay and Loam. 



e. Postglacial Deposits. 



/. Origin of the Blackpool Drifts. 



3. Drifts between Lancaster and Carn- 



forth. 

 a. Derivation of Limestone Boul- 

 ders. 



4. Denudation of Drift Deposits. 



a. Origin of Lake- and Swamp- 

 basins in Drift. 

 h. Subaerial Denudation of Drift 



Deposits. 

 c. Origin of Drift Escarpments and 

 Valley- plains, 

 6. Smoothed Rock-surfaces and Drifts 

 oftheFurness peninsulai 



a. Distinction between Glaciated, 



Rain-worn, and Sea-worn 

 Rock-surfaces. 



b. Eockwork of Birkrigg Moor 



and Hampsfell. 



c. 



near 



7. 



Glaciated Rock- surfaces 



Ulverstone. 

 Lower Boulder-clay or " Pinel " 

 between Bardsea and Bay- 

 cliff. 

 Pinel and Contorted Sand and 



Gravel near Ulverstone. 

 Contorted Sand and Gravel in 

 other parts of the Furness 

 peninsula. 

 Pinel at High Levels. 

 h. Upper Boulder-clay. 

 i. Drift Capping of Dunnerholme. 

 j. Upper Boulder-clay at Barrow. 

 k. Surface Boulders. 

 I. Sections obtained by Borings 

 near Ireleth. 

 Drifts of Whicham Yalley and 



Blackcombe. 

 Direction and Derivation of the 

 Flow of Granitic Drift in North- 

 west Lancashire. 

 Connexion between Boulder-drifts 

 and Superficial Accumulations 

 at High Levels. 



d 



/. 



9 



1. Introduction. 



Are the drifts of different districts merely local variations of one 

 great formation which cannot he systematically divided? or can 

 these deposits in their more persistent features he satisfactorily syn- 

 chronized over extensive areas ? As this is a very important ques- 

 tion, and as little or no notice of any attempt to classify or correlate 

 the drifts of the north-west of England has yet been communicated 

 to this Society, the author hopes that the following account of obser- 

 vations made during prolonged visits to Blackpool, Dlverstone, and 

 Lancaster in 1868-69 may not prove unacceptable. 



2. Coast-Section of Drifts at Blackpool. 



There are perhaps few parts of England where such extensive and 

 instructive sections of distinct kinds of drift are clearly exposed as 

 in the immediate neighbourhood of Blackpool. Beyond an acquaint- 

 ance with the fact, derived from the Geological Magazine *, that Mr. 

 Binney, P.E.S., had found sea-shells in, and had written on these 

 drifts about eighteen years agof, when the triplex division of drift 



* Mr. Darbishire on " Drift-beds," vol. ii. No. 7, July 1865. 

 t Memoirs of the Lit. and Phil. Soc. of Manchester, vol. x. 



