﻿MURCHISON— FLINT DRIFT OF S.E. ENGLAND. 



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where, in short, we read the same lesson, and learn that, having been 

 subjected to great dislocations, the hardest fragments of the Chalk- 

 formation have been mostly shivered into fragments and piled up in 

 heaps in one place, or poured tumultuously into cavities in another, or 

 interlaminated rudely with sand in a third. The whole tract, ranging 

 westwards by Box Grove Common, Stoney-fields, and the slopes of 

 Goodwood to the flat country north and north-west of Chichester, 

 and thence extending by Stansted Park, Aldsworth Common, and 

 Havant to the foot of Portsdown Hill and to Portsmouth, is covered 

 with similar detrital matter, including stiff clay and sand ; but with 

 these are invariably found heaps and masses of angular chalk-flints. 

 Nowhere do rounded shingle or true pebble-beds form part of this 

 rubbish, although I shall presently advert to a sample of such 

 rounded gravel which has had a very different origin and was formed 

 at a much older period. 



Those portions, for example, of the clay of Bere Forest, which are 

 also partially in situ, indicate, as at Newhaven on the east, the bottom 

 of an old tertiary trough between the chalk of the western extremity 

 of the South Downs on the north, and the chalk-outlier of Portsdown 

 Hill on the south. 



The zone of coarse flint-breccia in the south of Sussex has an east 

 and west range coincident with that of the South Downs, and through- 

 out the tract west of Arundel its northern edge is not less than six 

 miles distant from the present sea-shore. 



In some spots it rises to a certain altitude on the slope of the South 

 Downs, particularly between Slindon and Goodwood ; but its chief 

 masses have been lodged, as at Slindon Common, in the flatter ground 

 nearest to those hills, and have not been transported far from the 

 sources of their origin. 



The broad coast-flats of Little Hampton and Bognor have all 

 been more or less overspread with detritus, which, although of very 

 different value to the agriculturist, has had precisely the same origin 

 as the pure angular-flint-breccia of the hill- sides. No line of sepa- 

 ration can be drawn between the many flints with reddish clay, and 

 the few flints in copious masses of clay, loam, sand, &c. This plain of 

 rich arable land is chiefly composed of the breaking-up of the Plastic- 

 clays and sands, and of the London-clay, mixed together irregularly. 

 But these materials are interspersed with, and also slightly overspread 

 by, angular chalk-flints. Instead, however, of being dominant, as on 

 the higher slopes of the South Downs, the angular flints are much 

 more sparingly distributed through this clay or loam of the low coun- 

 try. In truth, any one who will examine the deep ditches north of 

 Bognor*, or the little portion of low cliff which is left at the west end 

 of that bathing-place f, will see that the detrital matter is exactly of 



* In justice to Lady Murchison, I must state that many years ago she detected 

 in the cuttings of the bluish drift of the fiats east of Bognor, and also near Angle- 

 sea, Gosport, many fragments of existing sea-shells in inland situations, consider- 

 ably removed from the present shore-line. 



t A careless observer might suppose that round shingle formed some part of the 

 argillaceous drift in this low cliff at Bognor. The pebbles, however, which are 

 partially seen are only external, and have been driven up by the present sea. 

 Within the mass every flint is more or less angular. 



