A HISTORY OF SURREY 



are followed westward ; so that in Surrey there is some doubt as to their 

 identification, and it is only in the tract between Reigate and Oxtead 

 that the middle division, or Sandgate group, is recognized on the 

 Geological Survey maps, though Mr. Meyer believes that it can be iden- 

 tified also in the west of the county. 1 



In Kent the lowest of these divisions, the Hythe Beds, is character- 

 ized by irregular bands and concretions of sandy limestone or ' Kentish 

 Rag,' often associated with layers of chert formed by the concentration 

 of silica derived from sponge-spicules, but in eastern Surrey it consists, 

 for the most part, of unconsolidated slightly loamy sand, with only occa- 

 sional nodular induration. These characters are modified, however, west 

 of Dorking, where the belt occupied by the Lower Greensand suddenly 

 expands from a breadth of less than a mile to nearly four miles, again 

 increasing to over six miles west of Guildford, under the influence of a 

 subsidiary fold of the strata which will be subsequently described. Some 

 parts of the division here become indurated into cherty sandstone ; and 

 in the Guildford district a hard calcareous sandstone or grit known as 

 4 Bargate Stone,' resting on pebbly sands, is developed in the upper 

 part, and this part contains, among other fossils, the teeth and scales 

 of many extinct genera of fish. Sponge-spicules may generally be 

 detected in the cherts, and the decay of such spicules appears to have 

 supplied the siliceous cement by which the sands are indurated. 2 This 

 lateral change in the composition of the beds is strongly reflected in the 

 physical features of the country; for while between Reigate and Dorking, 

 where the Lower Greensand includes very little hard material, its out- 

 crop forms a comparatively low broken terrace dominated by the Chalk 

 escarpment, it rises both eastward and westward into a bold hill-range 

 which on the west is higher than the Chalk Downs, with its culminating 

 points at Leith Hill (967 feet) and at Hind Head (894 feet) making the 

 highest ground in the county. 



In the district east of Reigate, where the Sandgate Beds of the 

 Lower Greensand have been recognized as a separate division, they consist 

 of alternations of soft sandstone with clayey material and fuller's earth, 

 having a total thickness near Nutfield of 40 feet or more. The fullers' 

 earth of this district is of considerable economic importance, having been 

 extensively worked from an early date for use in the preparing and 

 cleansing of cloth, and latterly for export to America for use in the 

 dehydrating of cottonseed-oil and other vegetable oils, which it is said can 

 then be used for adulterating lard. The demand for the former purpose 

 had gradually dwindled, but the new use for the material has given a 

 fresh lease of life to the industry. 



The upper division, or Folkestone Beds, is persistent in character 



1 'On the Lower Greensand of Godalming,' Proc. Geol. Assoc., sup. to vol. i., 1868 ; 

 see also T. Leighton, 'The Lower Greensand above the Atherfield Clay of East Surrey,' 

 Quart. Journ. Geol. Soc., vol. li. (1895) pp. 101-123, which contains full references to pre- 

 vious literature of the subject. 



* See Dr. G. J. Hinde, Phil. Trans., vol. clxxvi. (1885) p. 403. 



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