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 A HISTORY OF SUSSEX On referring to the geological map of Sussex the reader will notice that it is coloured various tints, which form belts extending east and west throughout the county. These belts represent the strata coming to the surface, or ' cropping out,' as it is termed, in succession, the oldest appearing towards the north-east and the newest towards the south and south-west. The cross-sections appended to the map will better explain this peculiarity. The geological structure of the county consists essentially of one big wave, with its crest near Battle, Horsham and Haslemere, and its parallel trough extending east and west under the English Channel a few miles south of the coast. Minor ripples or undulations somewhat modify the perfect regularity of the big wave on which they ride ; but they are comparatively unimportant, for while the height of the domi- nant wave, measured from crest to trough, is fully 4,000 feet, the minor ripples do not exceed 600 feet. The oldest rocks known within the county are the Jurassic deposits met with in the ' Sub-Wealden Boring,' a trial boring made in the year 1874 to explore the unknown deep-seated strata and to ascertain whether coal could be found within a workable depth. The most ancient strata exposed at the surface are those met with near Battle, where the crest of the high wave has been planed down so as to lay bare layers which else- where are only to be found far below the sea-level. To the neighbour- hood of Battle therefore geologists turned their attention when it was proposed to attempt to reach Coal Measures by boring through the Secondary formations. It was naturally thought that the lower in the series it was possible to commence, the less the thickness to be penetrated before Coal Measures or other Paleozoic rocks were reached. The experimental boring at Limekiln Wood in the parish of Mountfield however proved to be a failure, its main result being to show an enor- mous and quite unexpected thickening of some of the Jurassic clays, so that at 1,905 feet from the surface the boring was still in Oxford Clay, with no sign of a change and perhaps several thousand feet of Secondary strata still to penetrate. The small size of the cores obtained makes it difficult to say much about the lower strata, though sufficient fossils were discovered to prove the age of certain beds. Divisions however shade into each other in such a way, and the characters of the rocks are so diffisrent from the nearest outcrops, a hundred miles distant, that there is still some diffisrence of opinion as to the exact limits of each formation. In the following notes the grouping used by Mr. H. B. Woodward has been adhered to.' The lowest strata reached consist of 100 feet or so of dark shale, with a I 5 foot bed of limestone. In these shales were found specimens of A?}imonites chaimisscti, proving them to belong to the Oxford Clay. Next follow about 240 feet of more or less calcareous and sandy strata, with Rbynchonella piiiguis, a fossil characteristic of the Corallian rocks of ' 'Jurassic Rocks of Britain,' v. 345-7, Mnii. Gcol. Surra (1895) ; sec .ilso H. Willett, Record of the Sub-lVcalden Exploration (8vo, Brighton, 1878) ; and W. Topley, 'Geology of the Weald,' Mem. Gcol. Survey (1875). 4