106 MR. T. LEIGHTON ON THE LOWEK [May 1 895, 



section in Abinger Lane. It is not contended that the whole thick- 

 ness given to all the beds of this collated section was ever regularly 

 superimposed at any one place. I am of opinion that the beds of 

 Leith Hill show thickening of deep-water deposits to the south ; 

 nevertheless, whilst there is nothing to show that the whole 60 feet 

 of the upper beds may not have existed at the tower before denu- 

 dation, there is some evidence that the massive chert-beds decrease 

 very much in thickness to the north. 



In many places there is evidence that the whole of the beds of 

 Leith Hill incline west as well as north : this is clearly brought out, 

 however, by a comparison of levels about the parallel N. 51° 12' 30'. 

 At Damphurst Hollow, the top of Local Group 2 crops out here- 

 abouts close under the 500-foot contour ; in Wotton Lane to the 

 west the 400-foot contour must lie about 50 feet down in the 

 cherts (a fall of 50 feet), but in Baikes Lane at 380 O.D. we must 

 be much higher up in that series, if not at the junction with the 

 Bargates (a fall of 20 feet). Between the first and second of these 

 places the beds are no doubt affected by the north-and-south fault 

 at Abinger Bottom, although that lies a little to the south ; but 

 there does not appear to be any such disturbance between the 

 second and third. This rise of lower beds on the east of Leith Hill 

 lends a special interest to the section at Boar Hill, where at 560 O.D. 

 a cutting has recently been made towards the field-path leading to 

 Collickmoor Farm. The beds show a high dip arched over to the 

 west, and contain sandy cherts above, then beds of the massive 

 greensand 2 to 3 feet thick, with beds of soft sandstone, loose sand, 

 and thin clays, in bedded layers below. 



The sandy area of the Lower Greensand immediately north-east 

 of Leith Hill is sufficiently described eastward, as far as and including 

 the sections along the Horsham Boad, in the paper by Mr. Boulger 

 and myself already referred to. An interesting fact has come to 

 my knowledge this autumn, however, through a slip in the sandpit 

 at the 300-foot contour on the Horsham Boad, Section (C) of that 

 paper. 1 I was able, by means of this slip, to reach the top of the 

 section, where I found a well-developed bed of grit with pebbles 

 (the usual lydites, quartz, etc.) in a dark sandy matrix, which I 

 think there is little doubt must be the bed mentioned by F. Brew 

 on p. 134 of the Weald Memoir as having been useful to him in 

 mapping the base of the Folkestone Series hereabouts. This is an 

 extremely interesting discovery, because in our paper the base of 

 the Folkestone Series was drawn here upon altogether different 

 evidence. This bed has, I believe, been taken as the base of the 

 upper member of the Lower Greensand by all recent writers ; and 

 particular attention is drawn to it now, because it corresponds so 

 exactly with the bed at the same position in the series in the junc- 

 tion-pit in Abinger Lane, 2 and because it will be referred to 

 again later on. A bed of grit with similar pebbles occurs some feet 



1 Proc. Geol. Assoc, vol. xiii. (1892) p. 6. 



2 Ibid, p. 1(56 ; Quart. Journ. Geol. Soc. vol. 1. (1894) p. 729. 



