April 1, 1895.] 



KNOWLEDGE. 



91 



The Forest district is greatly faulted, which places lower 

 beds iu surface contiguity with higher in many places, and 

 so greatly diversifies the subsoils. 



The great ^^'eald ^'ale of Sussex is continuous with that 

 of Surrey, and, spreading to the west and south, forms a 

 broad area to the west of the Forest district, and extends 

 southwards and eastwards round its western end and along 

 its entire southern side. This is also a very extensive 

 area, and is altogether formed by the vast thicljness of 

 accumulated estuarine clays named the Weald Clay, which 

 here, as in Surrey, forms an undulating plain, and supports 

 abundant oak timber. The clay is variable in character 



into the English Channel. There is a considerable 

 amount of low flat laud in the river valleys, especially in 

 those of the Arun and the Ouse, which is formed of 

 Alluvium giving rich pasturage. 



The South Downs are the southern remnant of the great 

 sheet of Chalk that covered the whole area of the Weald 

 continuously with that now forming the North Downs. 

 The summit of the ridge and the southern gentle slope 

 consist, therefore, of the Upper Chalk, while the Lower 

 Chalk and the underlying Upper Greensand crop out on the 

 face of the northern steep slope or escarpment, the dip of 

 the beds being about 2° as in the North Downs, but to the 



etia<TOH 



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fa»CST OlSTHtCT 



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6 t;uitt I Upper Crreiunimt 9 Quilk t, AlltLVtt 



and is worked for both coarse brick and tile clay, and for 

 the finest terra-cotta clay, as at Ditchling Common. 

 Included in the Weald Clay are three thin beds of lime- 

 stone, one of which is called Sussex marble on account 

 of its containing abundant Paludinm, like the Purbeck 

 marble, and four beds of sands or sandstones, the lowest 

 of which constitutes the building stone known as Horsham 

 stone. 



The elevated district at the north-west of the county, 

 and curving round the west end of the Weald Yale to the 

 south, and then extending at a lower elevation to the east 

 on the north side of and roughly parallel with the South 

 Downs, is the Lower Greensand area of Sussex. This 

 formation does not form so large a proportion of the area 

 of the county as it does in Surrey, but attains almost as 

 great an elevation, for at Black Down it rises to 918 feet 

 above the level of the sea. 



All along the base of the northern steep slope or escarp- 

 ment of the South Downs there extends a series of vales 

 answering to the long valley of Holmesdale at the foot of 

 the escarpment of the North Downs, and having like it 

 a narrow outci'op of the Gault forming its bottom levels ; 

 and like it, too, separated from the Weald Clay Yale by a 

 Lower Greensand ridge, though of a less pronounced 

 character. This vale broadens where a river crosses to 

 enter the Chalk area, but the Gault is there covered by 

 Alluvium. South-west of Eye the outcrop of the Gault 

 widens considerably, as it does also in the west of the 

 county. 



The commanding range of hills, the South Downs of 

 Sussex, running from the Hampshii-e boundary to Beachy 

 Head, is about fifty-five miles in length, and attains an 

 elevation of 813 feet at Ditchling Beacon, which is 63 feet 

 less than the summit elevation of the North Downs, that 

 being 881 feet above the level of the sea. The following 

 heights above Ordnance Datum give the elevation of well- 

 known points on the range from west to east ; Treyford 

 Hill, 771 feet ; Cocking Down, 731 feet ; Duncton Down, 

 837 feet ; Bignor Hill, 738 feet : Kithurst Hill, 697 feet ; 

 Highden Hill, 667 feet ; Chanctonbury Ring, 783 feet ; 

 Cisbury Hill, 603 feet ; Truleigh Hill, 600 feet ; Devil's 

 Dyke, 697 feet ; Ditchling Beacon, 813 feet : Iford HUl, 

 610 feet ; Firle Hill, 700 feet ; Willingdon Hill, 665 

 feet ; Beachy Head, 512 feet. 



Like the North Downs, the South Downs are crossed by 

 four valleys, through which flow rivers that drain the 

 interior Wealden area. The four rivers crossing the area 

 of the South Downs are from west to east, the Arun, the 

 Adur, the Ouse and the Cuckmere, which all flow directly 



south instead of to the north. In the neighbourhood of 



Newhaven and of Seaford are outliers of Woolwich Beds 

 over the Chalk, and at Brighton there is the Temple 

 Combe deposit. The South Downs are not so extensively 

 covered at high levels with superficial deposits as are the 

 North Downs, and consequently are not so well wooded. 

 They give long stretches of beautiful sward, firm yet elastic, 

 affording magnificent walking and riding ground in the 

 purest atmosphere. They are traversed by paths, but in 

 many places so indistinct that they are easily lost, and at 

 Storrington the church bell is tolled, as in the old curfew 

 days, to guide belated travellers across the Downs. 



Although the great proportion of the area of the South 

 Downs is open grass-land, giving excellent pasture to the 

 far-famed South Down sheep, yet there are some splendidly 

 timbered parks on their slopes, for the noble parks of 

 Goodwood, Arundel, Angmering, and Stanmer are all on 

 the sunny southern slope of the South Downs. From 

 Beachy Head to Brighton the Downs form the coast, 

 giving lofty sea-cliffs ; then westwards, they leave the 

 shore-line and gradually recede from the sea, running 

 north of Cbichester to the Hampshire boundary. 



The area at the south-west of the county lying between 

 the Downs and the sea projects southwards, and forms 

 the promontory of Selsea Bill. This is the Tertiary 

 area of Sussex, the whole being formed by Eocene 

 formations though cverlaid by superficial deposits of 

 gravels, sands, and brick-earth. The Woolwich and 

 Beading Beds form the northern portion, the London 

 Clay the central, and the Middle Bagshot or Bracklesham 

 Clays the southern part. These formations are so obscured 

 by their covering of drift that the Middle Bagshots are only 

 seen at the sea-shore of Bracklesham Bay, while the beds 

 of London Clay age appear at the surface at Bognor only. 



The long coast-line of Sussex is greatly diversified in 

 elevation as it is in geological character. The low level 

 Selsea Bill at the west continues to Brighton with little 

 alteration of elevation, but thence to Beachy Head the 

 coast is bold, presenting lofty cliff's of chalk to the sea, the 

 clitl' at Biachy Head being 811 feet above sea level. From 

 Eastbourne to Hastings there is a stretch of low land 

 which is succeeded by the bolder coast of the Hastings 

 sands, with Hastings Castle at 189 feet, and Fairlight 

 coastguard station at 478 feet above sea level. The 

 alluvial flats at the mouth of the River Bother give a low 

 coast at the most eastern end of the Sussex coast-line, 

 corresponding to the west end of the county. Although 

 at some points shingle and blown sand are being 

 accumulated, at other places the coast is being vigorously 



