﻿Yol. 64.] JIE. H. BTJET ON THE EIVEK WEY. 319 



Blacknesfc Stream. The more important branch of Section lY, 

 onl}' a portion of which is shown in PI. XXXYl, rises in a deep 

 valley in the Lower Greensand between Blackdown and Hindhead 

 (from both of which it receives contributions), and flows at first 

 nearly due west to Liphook : there it turns north-westwards, and, 

 after being joined by a stream (marked as 'Deadwater' on the 

 Ordnance-Survey map) which receives the drainage of Woolmer 

 Pond, and of a large flat area to the west of Hindhead, it turns 

 north-eastwards to join the main trunk of Section lY not far from 

 Headley. It will be referred to later on as the Headley 

 Stream. 



Section Yisa short obsequent stream joining Section YI to 

 Section III at Tilford, which is thus the meeting-place of three 

 sections (III, lY, and Y). For convenience it may be called the 

 Waverley River, from the Abbey founded on its banks; but 

 there is no need to describe it here. 



Section Y I is another longitudinal river, parallel to Section lY, 

 but running close to the base of the Chalk escarpment. It follows 

 a very straight course from Alton to a mile east of Parnham, 

 where it joins Section Y almost at right angles ; but its continua- 

 tions above Alton are too complex to be described here. Both 

 this and Section lY are marked in the maps as the River Wey ; 

 but for the sake of clearness they will be referred to in this paper 

 as the Parnham and Tilford Rivers respectively. 



II. The Relation of the "VVey to the Blackwatee. 

 (Map, p. 320.) 



The former extension southwards of the River Blackwater is 

 recognized by Prof. W. M. Davis,^ but all that he says is that * the 

 Wey has recently taken ofi" the head of the Blackwater.' An attempt 

 will here be made to show some of the details of the process by 

 which this result was brought about, though unfortunately, owing 

 to the softness of the strata, but few definite traces of earlier stages 

 can now be found. The Parnham River, where it curves round into 

 the Waverley Yalley, is just 200 feet above O.D. This curve is 

 bounded on the north by a steep bank 50 to 70 feet high, and when 

 we have surmounted this, we find ourselves, after traversing a space 

 of almost level ground, slowly descending into the Blackwater Yalley. 

 The total width of the gap in the Chalk escarpment, which thus 

 forms a col between the two rivers, is, at the 300-foot level, 

 about 2 miles, but almost in the centre of the gap a mound of 

 Chalk rises to 295 feet, and thus divides it into two valleys (east 

 and west), each about 50 feet deep, and nearly a mile in width. 

 It is the western of these two valleys which lies opposite the bend 

 of the Farnham River (see Map, p. 320). A small stream, coming 

 down from Hungry Hill in an easterly direction, runs to the 

 bottom of this valley, and then, about opposite the Chalk mound, 

 turns abruptly southwards, and descends through a short ravine 



1 Geogr. Jouvn. toI. t (1895) p. 146. 

 a J. G. S. No. 254. Y 



