1870.] WOOD — WEALD-TALLEY DENXTDATION. 11 



because, though composed of angular flint and Tertiary pebbles, the 

 stream that passes Willesboro', a tributary of the Stour, does not 

 reach any way near to the chalk escarpment, while pits in the Lower- 

 Cretaceous stone are close at hand. In striking contrast with this 

 Willesboro' gravel is the gravel skirting the Stour at lowest level at 

 Bucksford, less than three miles west from that at Willesboro'. 

 This low-lying gravel is entirely made np of subcretaceous material, 

 though by long search a solitary fragment of flint may be found in 

 it, derived probably from the flints scattered over the Gault surface, 

 up to which some of the rivulets running into the Stour extend ; it 

 is obviously a deposit of the Stour when flowing in greater volume 

 in the same direction as at present. But, looking at the physical 

 and geological features of this part of the Weald, can it be con- 

 tended that a similar flow at from 50 to 100 feet higher level could 

 have deposited gravel of such opposite character to this as is that 

 hard by at Willesboro' or that, about 15 miles distant, on the heights 

 at Canterbury ? 



I would, however, prefer to deal with the possibility of these 

 pebbles reaching such positions on broader grounds than the precise 

 position of the rivulets nearest to their place of occurrence ; that is, I 

 regard their position as repugnant to any introduction from the Stour 

 or Medway, in their present direction, during the course of a pre- 

 longed atmospheric or fluviatile denudation which resulted in the pro- 

 sent excavation forming the Weald, for the following reasons, viz. : — 



1st. The form and character of the great Wealden denudation 

 area (or major valley), as distinguished from the valleys proper of the 

 Wealden rivers (or minor valleys), is diametrically opposite to any 

 that can result from river-action, because, however great we concede 

 the power of that action to be, any excavation resulting from it must 

 be conterminous with the excavating agent itself (the river and its 

 tributaries), since every stream, large or small, can only deepen its 

 own proper valley, and the result cannot be any such excavation as 

 the major valley of the Weald, with its well-known contour and 

 escarpments, but only a series of valleys, or minor excavations, 

 ramifying in the directions in which the stream extends, and in some 

 degree at least coinciding Avith them ; and the longer this action is 

 continued, the deeper and more distinct must these features become. 



2nd. If flints and pebbles were derived from the Chalk escarp- 

 ment, we should look for an increase in their number as the escarp- 

 ment is approached ; but though a few angular flints are in some 

 places scattered over the surface of the Gault, the Lower-Tertiary 

 pebbles seem wholly absent from that part of the area, and from the 

 sources of the streams supposed by some to have brought them. 



3rd. The Lower-Tertiary beds yielding pebbles are far away from 

 the escarpments, and rest on the northern extremity of the chalk 

 slope and below the crests of the escarpments ; and however high 

 the level be to which we carry our imagination of the flow of the 

 Wealden rivers in past times, even if up to the level of the escarp- 

 ment-top itself, still the drainage from the Lower-Tertiary strata 

 must at all times have flowed away from the scarp, and not into the 

 Weald. There are, however, some patches of pebble-beds (of date 



