DRIFT-STAGES OF THE DARENT VALLET. 141 



lies on the watershed *, and, though related to the Darent Valley, 

 cannot be referred to that river in its present form t- He observes 

 also that it is quite certain that the gravels of the Darent Valley 

 westward of Westerham have a distinct relation to that of Limps- 

 field (0^9. clt. p. 193). In this I quite agree, but I would extend 

 the relation considerably beyond these limits ; for, although the de- 

 tached outliers lower down the valley are affected by local conditions, 

 their general characters are alike. 



It is in this older and wider floor, of which only few portions 

 now remain, that the present valley-channel has been excavated. 

 One of these remaining portions caps Farley Hill, near Westerham, 

 two miles east of Limpsfield Common, and a short way north of 

 the course of the Darent (fig. 6, p. 139). 



The bed of gravel there is not so thick as at Limpsfield, and, like 

 it, is unstratified or very rudely bedded, and consists essentially of 

 angular and subangular flints with Tertiary flint-pebbles, but the 

 latter are in less proportion. Fragments of iron- sandstone from the 

 Lower Greensand are common, with a few rare specimens of Lower- 

 Greensand grit and of pieces of Tertiary conglomerate. There are 

 no organic remains, nor have any flint implements been hitherto 

 found, but there has been no long and sustained search like that 

 Mr. Bell has made at Limpsfield J. The difference of level between 

 the two beds is 51 feet, which gives to the old river- channel a 

 gradient of 25 feet to the mile. 



On the opposite side of the Darent, in the grounds of Squerryes 

 Court, and at a similar level (478 feet) there are traces of the same 

 gravel. These outliers are on a level of 116 feet above that of the 

 present stream of the Darent. Mr. Topley describes another small 

 outlier on the roadside E. of Squerryes Court and at about the same 

 level, and one on Moorhouse Common, between Limpsfield and 

 "Westerham, at the height of 485 feet §. 



From Farley Hill no high ground breaks the view for a distance 

 of five miles down the centre of the valley. The few patches of the 

 high-level gravel are all on the south side of the valley, and lie 

 on the slope of the Lower-Greensand hills. One is to be seen 

 in a small pit in the south-east corner of the grounds of Brastead 

 Park |j,2| miles from Westerham, and at a height of about 430 feet 

 above sea-level. The gravel is very similar to that on Farley 

 Common, but is more sandy and with more Lower-Greensand 

 debris, including large blocks of Iron-sandstone, and some fragments 



* On the east branch of the Darent Valley there are analogous but more 

 obscure remnants of gravel on the watershed at West Yaldham and on the 

 north slopes of Oldbury (see PI. VI., fig. 1, and p. 143). 



t For Mr. Topley 's discussion on this question, see ' Geology of the Weald, 

 pp. 289, 297, 298. He thinks the original river must have taken its course 

 farther to the W. or S.W. than now. 



J Froua this hill one has an excellent view down the valley, showing the 

 relation which this gravel bears to the Darent, to the Chalk Downs, and to the 

 Lower-Greensand range. 



§ ' Geology of the Weald,' p. 194. 



II Oi?. ciY. pp. 191, 192. 



Q. J. G. S. No. 186. L 



