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XVII. On the Anticlinal Line of the London and Hampshire 

 Basins. By P. J. Martin, Esq. 



[Concluiled from p. 39.] 

 Drift of the Denudation generally. 



THE most profitable line of study a man can take in this 

 matter, should begin at the top of the Hastings sands. 

 He should reverse my order of classification, and begin with the 

 Wealden zone, in which drift is to be found in its simplest state, 

 and proceed outwards from thence to the most complicated in 

 the valleys of the Thames and the Solent sea. In all the higher 

 districts of the Hastings sand country, on the slopes of the hills 

 which overhang the Rother and the rivulets which discharge 

 themselves by the longitudinal valleys of the Wealden district 

 eastward into the sea, and on their borders above the range of 

 modern silt, he will find the detritus I have described*, — in 

 soQie cases a slight sprinkling, in others heaped together in un- 

 mistakeable beds of diluvial drift. 



Leaving these districts, and proceeding outwards over the 

 Weald clay country, the same kind of drift will be found lying 

 in hollovvst, and being occasionally turned up by the plough, 

 concreted iuto a breccia locally called " Iron rag," and once in 

 some parts of Sussex largely smelted in the iron furnaces of that 

 county. More remotely still, the observer will find this rag 

 beginning to include angular fragments of chert ; and as he ap- 

 pi'oaches the greensand country, to this angular breccia are added 

 flints, at first in small, but soon in larger proportions. 



To a diligent observer, some other indications which may rank 

 in the order of drift, and marking the progress of denudation, 

 will attract his notice. Where the country appears to be bare of 

 drift, some debris proper to the position will turn up in ploughed 

 fields, and in woodlands lately brought into cultivation. Near 

 and immediately around the Hastings sand country these debris 

 will be isolated fragments of stone, perhaps impressed with Cypris 

 or some other characteristic fossil ; more in advance, and before 

 coming to the outcrop of that stratum, fragments of Petworth 

 marble, a little weathered or water-worn ; a little further, and 

 still in the Wealden zone, boulder-like fragments of the ironstone 

 (carr-stone) of the lower greensand will appear in like manner, 

 and so to the foot of the greensand escarpment J. 



* Phil. Mag. October 1851. 



t I have described these hollow places in the clays in my former essay 

 as havinfi; been evidently scooped out by running water in violent agitation, 

 and filled up ugain with drift, like the similar hollows in the soft sand-rock 

 of the lower greensand. 



X My intimate acquaintance with the surface of the Weald where drift 



