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CHAPTER XIII. 



ON THE SUSSEX BEDS, OR WEALDEN, CONTAINING REMAINS OF LAND 

 PLANTS, AND AMPHIBIOUS AND FRESH-WATER ANIMALS. 



Extent of the Sussex Beds. — Their Geological Position and Mineral Characters. 

 — Remarkable Organic Remains of enormous Lizards and Plants, analogous to 

 those of Tropical Climates found in the Sussex Beds. — Supposed Appearance 

 of the Country when these Animals flourished. — Petvvorth Limestone. — Hast- 

 ings' Sand and Weald Clay. — The Wealden Beds formerly furnished the great- 

 est Part of the Iron manufactured in England. — Mr. Mantell's Enumeration of 

 the Species of Terrestrial and Fiesh Water Fossil Remains in the Wealden 

 Beds. — Observations on the Wealden Beds, and the Change from Marine to 

 - Fresh Water Formations. 



In an elementary treatise on Geology, it is desirable to present to 

 the view of the reader, not the geology of a single country, but that 

 of the whole globe, as far as it has been ascertained. In certain 

 countries, particular formations occupy a considerable extent, and are 

 of great thickness ; in other countries, similar formations are often 

 wanting altogether, or the beds are so thin as scarcely to excite no- 

 tice. The secondary strata cover more than one half of England, and 

 hence the English geologist might be suspected of bestowing upon 

 them too great a portion of his attention ; but a more accurate exam- 

 ination of other countries has fully proved, that many of the British 

 strata, which were formerly believed to be of very limited extent, 

 are spread over a great part of Europe, and preserve the same order 

 of succession as in our own island : — a description of these strata is 

 therefore an essential part of general geology. The formations of 

 the magnesian limestone, the red marie, the lias, the oolites, and 

 the chalk, have risen into geological importance within the last fifteen 

 years ; and the reproach cast upon South Britain by our neighbors 

 on the other side of the Tweed, namely, " that there was little or 

 nothing in England worth the attention of a geologist," has lost all 

 its force. The beds of sand and clay, that intervene between the 

 upper oolites and the chalk, were, however, still more recently re- 

 garded as unworthy of particular notice, but the labours of Mr. 

 Mantell and of Dr. Filton have made us acquainted with facts re- 

 specting these earthy and sandy deposits, which are scarcely ex- 

 ceeded in interest, by any discoveries in the lower strata. 



The beds which are about to be described as the Wealden, be- 

 cause they occur principally in the Wealds of Kent and Sussex, are 

 supposed to rest on the upper beds of oolite in these counties : they 

 dip under the chalk hills by which they are every where surrounded, 

 except on the east, where they are cut off by the sea. The oolite 

 below, and the beds of chalk and green sand above, are admitted to 



