1855.] MARTIN — DRIFT-DEPOSITS OF WEST SUSSEX. 135 



troughs of tertiary deposits. Eastward from the Forest of Bere the 

 tertiaries of the northern synclinal have been much denuded, and 

 are mixed up with an enormous quantity of drift, to he hereafter 

 described. They emerge again from this drift, and appear in con- 

 siderable force in the high grounds between Chichester and Arundel, 

 in Eastergate, Walburton, and Binsted. East of the Arun, again, 

 they expand into the woody districts of Angmering, Clapham, and 

 Castle Goring in the rear of High Down, where a great mass of 

 eocene gravel has long been worked out for economical purposes. 

 The southern synclinal is occupied by the well-known Bognor beds 

 and the Bracklesham eocene ; and these and the London Clay, or 

 its equivalent, form the basis of all the flat country south of Chi- 

 chester, called the Manhood. I do not think that the Bracklesham 

 beds have any inland outcrop ; but the London Clay is extensively 

 exposed in Siddlesham, Birdham, and the north part of West Witti- 

 ring. Wells in the last-mentioned parish have furnished me with 

 the geodes or septaria of the London Clay ; but I have not been 

 able to pick up any fossils from the same. The cement-stone is also 

 dredged up in the adjoining part of Chichester Harbour. Wells and 

 excavations in the southern part of Birdham and in Earnly furnish 

 a fawn-coloured micaceous sand — perhaps the Thanet Sands. 



This will suffice to prove that the basis of all the plain south of 

 Chichester is the stratified beds which assimilate to those which 

 occupy the valley of the Thames. A great deal of drift reigns para- 

 mount over all ; and the most interesting part of this material is the 

 deposit to be found south of Siddlesham, — consisting of loam or 

 brick-earth, extensive beds both of rounded gravel and angular flints, 

 the former much predominating, with large boulders of granite and 

 other crystalline rocks ; the whole exhibiting much of the hetero- 

 geneous and tumultuary character of the boulder-drifts of the eastern 

 counties. 



The high grounds of Selsey are entirely composed of these de- 

 posits. Extensive shingle-beds spread in all directions through the 

 eminence on which the village of Selsey stands, which eminence 

 rises 25 or 30 feet above the sea ; and they are carried on eastward 

 about the church, and on into the flat called the Harbour, a branch 

 of Pagham Harbour, producing there a remarkable phsenomenon 

 called the " Hushing Pool," described by the county historians as 

 amongst the most remarkable natural curiosities of this district*. 

 The boulder-drift dies out as we come north from Selsey, though 

 there is good reason to believe that it was once spread over all the 

 district, for large masses lie here and there over the parishes of Bird- 

 ham, Siddlesham, and Hunston, or are occasionally brought to light 

 by the plough f. 



North of Hunston and Donnington, and of all the chalk-anti- 



* It is simply the bubbling and hissing produced by the disengagement of the 

 air from the gravel before the incoming tide. 



t The font of Yapton Church is of granite, which, if not found on the spot, 

 was most probably not brought from any great distance, as the fonts of this 

 country are mostly of Purbeck marble. 



