182 /iN ENGLISH SII/h'E. 



of the sea, we ought now to find the whole country a flat 

 and level table-land, covered over its entire surface with 

 a uniform coat of Tertiary deposits. On digging or 

 boring below these, we ought to come upon the chalk, 

 and below the chalk again, with its cretaceous congeners 

 the greensand or the gault, we ought to meet the Weald 

 clay and the Hastings sand. Wherever a seaward cliff 

 exhibited a section for our observation, we ought to find 

 these same strata all exposed in regular order — the sand- 

 stone at the bottom, the clay above it, the broad belt of 

 chalk halfway up, and the Tertiary muds and rubbles at 

 the top. But in the county as we actually find it, we 

 get a very different state of things. Here, the surface at 

 sea-level is composed of London clay ; there, a great 

 mound of chalk rises into a swelling down ; and yonder, 

 once more, a steep escarpment leads us down into a 

 broad lowland of the Weald. The causes which have 

 led to this arrangement of surface and conformation 

 must now be considered with necessary brevity. 



The North and South Downs, with all the country 

 between them, form part of a great fold or outward bulge 

 of the strata above enumerated, having its centre about 

 the middle line of the Forest Eidge. Imagine these 

 strata bent or pushed upward by an internal upheaving 

 force acting along that line, and you will get a rough 

 picture of the original circumstances which have led to 

 the existing arrangement of the county. You would 

 then have, instead of a flat table-land, as supposed 

 above, a great curved mountain slope, with its centre on 

 top of the Forest Eidge. This gentle slope would rise 

 from the sea between Chichester and a point south of 



