A HISTORY OF KENT 



that the uppermost portion of the Folkestone Sands should be classed 

 with the Gault,^ 



In their prolongation inland the stony bands of the Folkestone 

 Beds soon disappear, so that to the westward of Saltwood the division 

 consists for some distance almost entirely of sharp ' false-bedded ' sands 

 with irregular lines of ironstone. West of the Medway however, near 

 Ightham, the sands again include impersistent masses of extremely hard 

 glauconitic siliceous stone ('Ightham Stone' or 'Firestone'), and a 

 similar rock was found in the much attenuated Folkestone Beds passed 

 through in the colliery sinkings at Dover. 



The coarser sand-grains of the deposit are frequently extremely 

 well-rounded and polished, as though by long-continued attrition in the 

 shifting sandbanks of the current-swept sea floor, and these smooth- 

 worn grains are particularly noticeable in the band containing the 

 phosphatic nodules near the top of the sands. This band probably 

 marks a falling off in the supply of sandy material as the waters became 

 deeper and the shore-line more distant, and foreshadows the approach of 

 the conditions under which the Gault was afterwards deposited. Where 

 unmodified by ' superficial ' accumulations, the Folkestone Beds make a 

 thin sterile soil, and such tracts are only partly cultivated. 



SELBORNIAN 



Gau/t— With the deepening and expansion of the sea basin the 

 sand-bearing currents ceased to reach the district, and only the finer 

 muddy material sank through the quiet waters to this part of the sea- 

 floor. This sediment accumulated to form the Gault, a more or less 

 calcareous clay, in which are embedded the beautifully preserved shells 

 and other remains of marine organisms of the period that gladden the 

 heart of the collector who examines the famous section exposed on the 

 coast at East Wear Bay near Folkestone. For the splendour and variety 

 of its fossils this locality is unrivalled in Kent and is scarcely equalled 

 elsewhere in the British Islands. 



They include many species of Ammonites, Hamites and other allied 

 cephalopods, with Nautilus and Belemnites ; bivalve and univalve shells 

 in abundance and of wide variety ; crustaceans of several kinds ; small 

 corals ; many foraminifera ; the teeth and bones of fish and reptiles ; 

 and a few plant remains.^ 



Many of the shells still possess their original pearly iridescence, 

 and can be separated from the soft clayey matrix with all their delicate 

 markings and ornamentations intact. Being usually impregnated with iron 

 pyrites however, they decay rapidly when exposed to the weather, so that 

 it is only in freshly-cut sections on the shore or at the foot of the cliff 

 that they can be obtained in good condition. They are more abundant 



' For recent discussion of this point, with description of the 'zone of Am. mammillalus' at 

 Folicestone, see Mem. Geol. Survey, 'The Cretaceous Rocks of Great Britain,' i. 43, 73. 



2 The reptilian and fish remains of the Gault are described in the context : see article ' Palsonto- 

 logy,' P- 3'- 



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