Dr. FiTTON on the Strata below the Chalk. 143 



on the south by almost rectilinear escarpments, projecting successively be- 

 yond the narrow and comparatively regular line of the previous outcrop, 

 on the east*. The breaks between these steps coincide with the gorges of 

 the Mole and the Wev; a fact in favour of the hypothesis which ascribes the 

 formation of these gorges to transverse fissures. 1. — The first of these tracts 

 of sand lies between Leith Hill and the opening cut across the sands towards 

 Guildford, by the south-eastern branch of the Weyf, in which the Surrey 

 and Sussex canal has been dug. Its southern verge extends from Leith Hill, 

 through Holdenbury Hill, to Bearland and Stroud-Green, with a mean 

 breadth from the chalk of about 3^ miles. 2. — The next step projects about 

 3 miles further south, with an average breadth of about 6 miles ; and its 

 escarpment is nearly parallel to the Hog's-back throughout the greater part 

 of its length, from the Telegraph Hill, south of Hascombe, to Emily Farm, 

 a little east of the centre of a line from Hindhead to Thursley. The anticlinal 

 line, hereafter mentioned, along the top of Grayshot Down, may perhaps be 

 the continuation of a ridge^ or saddle, of which the beds rising towards 

 Hascombe are the remaining northern portion, the southern slope having 

 been carried away by denudation j;. 3. — The sands on the north of the valley 

 between Ludgershall and Harting-combe, may possibly be considered as a 

 third step in these parallel outcrops, though much less regular than the two 

 just mentioned : the lofty summit of Blackdown, at its eastern extremity, 

 is standing out like a promontory, about two miles beyond the other parts of 

 the escarpment on the south of Hindhead. It is impossible not to connect 

 these appearances with the general action of the force by which the whole of 

 this country has been upheaved; all the features coinciding with the hypo- 

 thesis of its elevation on a line or lines parallel to the axis of the forest 

 ridge. 



(55.) Dorking to Leith Hill, ^c. — ^The tract between Leith Hill and 

 Guildford affords nothing particularly deserving of notice, except the great 

 height (993 feet) to which the outcrop of the lower green-sand rises, at the 

 point on which the tower is placed. The space included between the escarp- 



* To understand the structure of this country, the reader ought to have before him a map on a 

 much larger scale than that in Plate IX,, as Mr. Greenough's Map of England ;— or the eighth 

 sheet of the Ordnance Survey, — which, however, is by no means equal, in correct representation 

 of the surface, to the more recent portions of that work. 



•}■ This stream has no name in the Ordnance map. 



X Another anticlinal line, but in a direction oblique to that here mentioned, is indicated by the 

 line of heights which runs from Milford, through Godalming, and thence by Unsted and Sum- 

 mersbury to Western Street, near Albury ; the strata on the south-east of this line, near Godal- 

 ming, dipping at a'small angle to the south-east, obliquely from the range of the Chalk Downs. 



