SOUTH-EASTERN DIVISION OF SUSSEX. 15 



Compton. Their length is between fifty and sixty miles, their greatest 

 breadth seven miles, and their mean altitude about five hundred feet 

 above the level of the sea. Their northern escarpment is in general steep 

 and abrupt, but on the south they descend by a gentle dechvity, and 

 unite almost imperceptibly with the low lands of the coast. 



From Beachy-Head to Brighton, they present an immediate barrier 

 to the sea, forming a bold and precipitous line of coast ; but proceeding 

 westerly, they extend inland in an obHque direction, and occupy the 

 centre of Western Sussex. From this circumstance, a considerable 

 difference exists in the geological relations of the eastern and western 

 divisions of the county ; the latter being characterized by a range of 

 chalk hills in the centre, with a maritime district formed of clay and 

 gravel on the south, and a weald composed of sand and clay on the 

 north. 



Throughout its whole extent this chain exhibits decisive manifestations 

 of the action of water ; not only are the ridges and summits of the hills 

 rounded and even, but their surface is every where furrowed by coombes, 

 or narrow undulating ravines ; these uniting terminate in vaUies, that inter- 

 sect the downs in a direction nearly north and south, and form extensive 

 outlets for the rivers that flow from the interior of the country into the 

 British Channel. The course of the smaller excavations or coombes is 

 exceedingly various, but their general bearing is east and west; they 

 gradually increase in breadth as they descend, and their opposite sides 

 have corresponding angles and sinuosities ; this appearance however is not 

 observable in the principal valhes. 



The chalk hills of Sussex are separated into five distinct masses, by 

 the following rivers ; viz. the Arun, the Adur, the Ouse, and the Cuckmere. 



The first is situated in Western Sussex : it rises in the forest of St. 

 Leonard, near Horsham, and taking its course to the westward for a few 

 miles, turns suddenly to the south, passes through the chalk near Arundel, 

 and falls into the sea to the west of Little Hampton. 



The Adur constitutes the western boundary of the South Downs, 

 properly so called; Hke the former, it has its origin in St. Leonard's 



