﻿Vol. 64.] ME. H. BTJET OK THE EIVBR WET. 323 



to Tilford, but also by a remnant of the old obseqnent river-bed, still 

 traceable on the right bank from Tilford up to about the mouth of 

 the Bourne, and exhibiting, as we might expect, a steeper gradient 

 than the present river. Traces, too, of the old consequent river 

 are to be found on this side, but they will be discussed in § III. 



Two points in connection with the old river-bed between the 

 Wey and the Blackwater must be dealt with briefly before we leave 

 the subject. 



(1) It has already been mentioned that Lower Greensand frag- 

 ments are less common in the gravels lying in this pass (' Water 

 Lane/ etc.) than in the older gravels on the Fox Hills. The explana- 

 tion of this is simple : the latter (nearly 400 feet above Ordnance- 

 datum) received their supply direct from Hindhead by way of the 

 consequent river ; but the gravels of Water Lane (about 250 feet) 

 were laid down long after the capture of the consequent river, and 

 their Hythe-Bed pebbles therefore were only derived at second hand 

 from the older gravels bordering the Farnham Yalley. 



(2) In the preliminary description of this region it was seen 

 that a stretch of nearly level ground separated the Blackwater 

 from the edge of the steep bank which bounds the Farnham 

 Yalley on each side of Bourne Mill. It might be expected from its 

 origin that most of this old river-bed would drain towards the 

 Blackwater ; but such is not the case. The actual turning-point, 

 so far as I can ascertain, is at a spot to the east of Weybourne 

 House, marked 247 feet on the 6-inch Ordnance-Survey map, 

 about 1500 yards from the Farnham River, and half that distance 

 from the Blackwater. It happens that this point is close to, if 

 not on, the line of fault, as mapped by the officers of the Geological 

 Survey ; and it is, therefore, just possible that some slight earth- 

 movement has taken place here in recent times. Perhaps, however, 

 it is more probable that this is a case of ' aggrading ' — the Black- 

 water, which comes down from Hungry Hill almost at right angles 

 to the plain, having deposited so much sediment as to dam back 

 the drainage of the marshy land to the south. In either case a 

 very small alteration of level would be sufficient to give rise to the 

 present conditions. 



III. The Paljsolithic Geavels of Faenham. 



The high ground between the Tilford and Farnham Eivers, from 

 the Blacknest Valley (opposite Bentley) in the west to the Waverley 

 Valley in the east, is readily divided, as the map shows ( PI. XXXVI) 

 into a western or Alice-Holt area and three parallel ridges ; but 

 there are good grounds for believing that these ridges have been 

 only recently separated, and that the whole must be regarded as 

 the dissected remnant of an old plateau of river-origin. Only one 

 small patch in the north-western corner of Alice Holt rises above 

 the 400-foot contour, but almost the whole of the ground shown 

 on the map as being above 300 is, in fact, more than 350 feet above 

 Ordnance-datum. The plateau shows, especially along the northern 



