﻿Vol. 64.] ME. H. BUEY ON THE EIVEE WET. 329' 



It will be seen that tlie valley-system in the Chalk round Alton 

 is complex, and presents several features by no means easy to 

 understand. The district is knov^n to present a number of sub- 

 sidiary folds, ^ and when these are worked out in detail they will 

 probably throw light on the river-system ; at present, however, they 

 are not, so far as 1 can gather, sufficiently well known to be of much 

 assistance. Eut although we are unable to follow all the steps in 

 the evolution of this system, we may perhaps allow ourselves some 

 speculation as to its most salient feature — the connection with the 

 AVealden area. It will, I tliink, be evident from the foregoing de- 

 scription, and it is still more obvious on the ground itself, that this 

 valley-system was established at a very early period, when the 

 Chalk spread much farther to the east than at present, and that its 

 connection with the Wealden area is clearly secondary ; but where, 

 then, did it discharge its waters before this connection was made? 

 The first suggestion that presents itself, as a possible working hypo- 

 thesis, is that the Tisted Stream is the remnant of an old consequent 

 river, which joined the Whitewater by way of the Golden Pot, and 

 was afterwards captured by the Earnham River, which we will 

 regard for the present as a subsequent river belonging to the 

 Wealden area. It will be worth while to examine in some detail 

 the various propositions involved in this hypothesis. 



(1) Is the Tisted Stream the remnant of a consequent 

 river ? — The main water-parting in the western area of the Weald 

 is formed by the Petersfield anticline. In it one of the western 

 branches of the Wey (Deadwater) rises not far from Liphook, while 

 it is easy to trace its connection with those branches of the Eother 

 which join that river at Iping and Selham. The westernmost 

 branch of the Eother, it is true, appears to be an exception, since 

 it reaches almost as far north as Selbourne ; but I do not believe 

 that this represents its primitive position. The way in which it 

 follows the soft beds of the Lower Greensand round the curved end 

 of the Wealden dome suggests strongly that its presence north of 

 the anticline is due to a modern encroachment, assisted possibly by 

 the beds having been already levelled by the river to which 

 Woolmer Pond belongs. Anyone who visits the district will see 

 that it is still encroaching, and that it is likely at no very distant 

 date to capture Woolmer Pond itself. 



This view is borne out by a study of the Chalk district im- 

 mediately to the west of Petersfield ; for here we find the Meon 

 River rising in the anticline and flowing southwards, while our 

 Tisted Yalley starts from a point only a little to the north of this 

 line. It is therefore very unlikely that there should be, in so 

 narrow an area, separate lines of water-parting for this branch of 

 the Rother and the rivers on either side of it. 



Farther west again, although the Petersfield anticline is still 

 traceable, it is no longer dominant ; and the Rivers Itchen, Test, 

 and Avon, in a gradually lengthening series, take their origin in 



^ ' The Cretaceous Rocks of Britain— The Upper Chalk of England ' Mem. 

 Geol. Surv. rol. iii (1904) p. 183. 



