Geological Society of London. 387 



plains, -while the valley-gravels of the district have afforded mam- 

 malian bones and teeth of the usual species. Flint implements 

 have been found at Bournemouth at 120 feet above the sea, at 

 Lymington, near Southampton, at 80 and 150 fefet, and also along 

 the shore between Southampton Water and Gosport, at 35 feet above 

 the sea, from gravel forming part of the covering of the tabular 

 surface, and unconnected with the river- valleys. 



The gravel capping the cliffs of the south coast of the Isle of 

 Wight, in which the remains of Elephas primigenius have been 

 found near Brook and Grange, was probably deposited in the same 

 river-basin as the mammaliferous gravel of Freshwater ; and the cut- 

 ting back of the coast-line by the sea has given the tributaries of a. 

 river which flowed by Freshwater northwards to the Solent a direct 

 outfall to the sea ; and the streams thus intercepted at a high level, 

 under the changed condition of flow, have originated the Chines. 



The gravel clifi" of the Foreland, at the eastern end of the Isle of 

 Wight, consists principally of raised shingle, which towards the 

 south thins out, and is overlain by a thick deposit of brick-earth, a 

 continuation of which caps the cliffs up to the Chalk, and in which 

 a flint implement was found by the author at 85 feet above the sea. 



General Considerations. — The marine gravel, with granite boul- 

 ders covering the south of Sussex, is continued westward by the 

 gravel with similar boulders covering Portsea Island ; and this again 

 by the Hill-head gravels, with large blocks of Sarsen stone, these 

 lower gravels being bordered on the south by the raised shingle de- 

 posits of the Isle of Wight, and on the north by the higher marine 

 gravels of Avisford, Waterbeach, and Bourne, from which the lower 

 gravel is divided by a well-marked step, extending beyond Ports- 

 down Hill to Titchfield, and traceable on the west of Southampton 

 Water. The Hill-head gravels are considered to be an estuarine 

 deposit, of the same age as the marine gravels of Sussex, and the 

 low level gravels of the river-valleys ; they are supposed to have 

 been formed when the Isle of Wight was still joined to the main- 

 land, and all the rivers now reaching the sea by Poole Harbour, 

 Christchurch Harbour, Southampton Water, etc., were affluents of a 

 river communicating with an estuary opening to the sea in the 

 direction of Spithead. 



The gravels lying above the step, such as those of Avisford and 

 Waterbeach, Titchfield Common, Beaulieu Heath, and Bournemouth, 

 are looked upon as equivalent in position and age to the high-level 

 valley gravels. 



The level of the gravels on the highest parts of the table-lands 

 is such as to indicate an age far greater than that of the highest 

 gravels of the river- valleys ; but the uniform surface from the 400- 

 feet level downwards points to a long continuance of similar con- 

 ditions, during which the gravel from the highest levels to that of 

 the Bournemouth cliffs was deposited. The area that can with any 

 probability be assigned to the catchment basin of a river such as 

 that which has been before alluded to, is only three-quarters of the 

 basin of the Thames above Hampton, within which it is difficult to 



