AN ENGLISH SHIRE. 179 



From the great central boss of the chalk system in 

 Salisbury Plain, two long cretaceous horns or projections 

 run out to eastward towards the Channel and the 

 German Sea. These two horns, separated by the deep 

 valley of the Weald, are known as the North and South 

 Downs respectively. The first great spur or ridge passes 

 through the heart of Surrey, and then forms the backbone 

 of Kent, expanding into a fan at its eastward extremity, 

 where it topples over abruptly into the sea in the sheer 

 bluffs which sweep round in a huge arc from the North 

 Foreland in the Isle of Thanet, to Shakespeare's Cliff 

 at Dover. The second or southernmost range, that of 

 the South Downs, parts company from the main boss in 

 Hampshire, and runs eastward in a narrower but bolder 

 line, till the Channel cuts short its progress in the water- 

 worn precipice of Beachy Head. Between these two 

 ranges of Downs lies the low forest region of the Weald, 

 and between the South Downs and the sea stretches a 

 long but very narrow strip of lowland, beginning at 

 Chichester, and ending where the chalk cliffs first meet 

 the shore beside the new Aquarium and Chain Pier at 

 Brighton. Thus the whole of Sussex consists of three 

 well-marked parallel belts : the low coast-line on the 

 south-west, the high chalk Downs in the centre, and the 

 Weald district on the north and north-west. As these 

 three belts determine the whole history and very existence 

 of Sussex as an English shire, I shall make no apology 

 for treating their origin here in some rapid detail. 



The oldest geological formation w T ith which we have 

 to deal in Sussex (to any considerable extent) is the 

 Wealden : so that our inquiry need not go any farther 



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