84 Proceedhi/is. 



Nutfield and Bletchingley. The members assembled at Mill 

 Street, near the arch of the Brighton Eailway, proceeding 

 down Mill Street to the brook here crossed by a bridge ; this 

 stream is one of the sources of the Eiver Mole, the most 

 northern and most eastern of the feeders ; it di-ains the valley 

 lying between the Chalk range and the Lower Greensand 

 range. This valley extends from north to south about two 

 miles, and from east to west about four miles ; and the brook 

 is the only outlet for the drainage of that district. There are 

 evidences that at no very distant period the lower part of the 

 valley was frequently under water, and it is exceedingly pro- 

 bable that at some more distant time it was the bed of a lake. 

 A superficial clay is found lying on the Gault Clay, forming 

 the substratum of a considerable part of the valley, and 

 covering also on its south side the Lower Greensand forma- 

 tion; of this superficial bed of clay, bricks are largely made. 

 Leaving the brook, and passmg under the South Eastern 

 Eailway, the road ascends the south side of the Lower 

 Greensand range. Here we note one of the deep sandy lanes 

 which abound in the Greensand series, and which form a 

 very picturesque feature iu the scenery of the neighbourhood 

 and of this geological series wherever it extends. No satis- 

 factory explanation has been given, so far as the writer 

 knows, as to tlie formation of these deep lanes, often rocky 

 as well as sandy ; that they are partly water-worn is probable 

 from the fact that in most cases the roadway is not a gradual 

 incline, but is much steeper in the middle of the ascent than 

 towards the top or near the bottom. It seems as if a rush of 

 water had swept the loose soil from the upper part, the 

 current being stronger about midway, and deposited the soil 

 at the bottom, so lessening there the sharpness of the descent. 

 After quitting the deep lane, the road runs eastwards on the 

 side of the hill, the view south being very extensive and 

 beautiful, overlooking the Weald, and reaching to the line of 

 hills once covered with extensive forests, of which remains 

 exist in Ashdown, Tilgate, and St. Leonard's Forests. Con- 

 tinuing east, the road descends somewhat to a level of 

 the Wealden, but on the left or north of the road the 



