176 MR. W. J. LEWIS ABBOTT ON THE [May 1 894, 



Green, by which, time their upturned edges are cut through, thus 

 exposing the underlying Hythe Beds, estimated not to exceed 

 100 feet. The latter are also much denuded, and a few hundred 

 yards east of the section are cut through to the underlying Ather- 

 field Clay, the thickuess of which is estimated at 27 feet. Both the 

 last-named beds appear on the face of the escarpment, where the 

 Atherfield Clay is underlain by the Weald Clay. 



The altitude at which the Shode now rises is 400 feet, and its level 

 at Plaxtol is about 150 feet, the high ground on the summit of the 

 banks of the valley at Shingle Hill being 550 feet higher : conse- 

 quently, allowing the full thickness, 127 feet, for the Hythe Beds 

 and Atherfield Clay, the stream ought to flow for the most part in the 

 Weald Clay, and by the time it reaches Plaxtol it ought to have high 

 clay-banks, exposing 423 feet of Wealden Beds. Such, however, is by 

 no means the case. Fig. 2 (p. 174) shows a section from Shingle Hill, 

 through Plaxtol to Hurst Wood, between figs. 8 and 4 of Prof. Prest- 

 wich. 1 Here the stream is seen, at 150 feet O.D., to have only just 

 entered the Weald Clay, and one also notices that the high towering 

 sides of its valley are composed almost entirely of ' Kentish Bag,' 

 which extends to an altitude of 700 feet, although the deposit is 

 only 100 feet thick. Moreover the Mote stream is seen to cut quite 

 through the Hythe Beds at an altitude of nearly 400 feet, thus 

 showing that the valley, iustead of being one of simple erosion, is 

 for the most part one of depression. 



If we take a section along the Shode Valley (see fig. 3, p. 175) we 

 find that such a depression really has taken place, approximately, 

 from Plaxtol in a N.N.W. direction to below St. Clare. To this 

 depression the yielding Gault Clay lent itself by forward progression, 

 at right angles to the depression, by which the outcrop of the Gault 

 is nearly doubled in width, as shown in the Geological Survey map 

 of the district (Sheet 6), The Folkestone Beds, when made up of loose 

 sand, also lent themselves to the stretch, but when more compact 

 they cracked ; the limestones of the Hythe Beds, on the other hand, 

 became very much fissured. 



For the purposes of this paper it is not necessary to enter 

 further into the earlier geological history of the valley ; of this, with 

 the anthropological succession in the district, I hope to treat fully 

 on another occasion. The exact date at which the depression took 

 place has little, if any, chronometric value in connexion with the 

 contents of the fissure : whether it was in the early stage of the 

 Holmesdale Valley, when the Bag had 250 feet of Gault and Folke- 

 stone Beds above it, or whether it was after the river had actually 

 pierced the former beds, is uncertain. One time-recorder remains, 

 and that is, the amount by which the river has lowered its channel 

 since its debris- charged waters first gained egress into the fissures, 

 till the time when they were no longer able to do so. 



An examination of the existing features of the surrounding 

 country indicates that the Shode when it first entered the Hythe 



1 Op. supra cit. p. 272. 



