﻿MURCHISON — FLINT DRIFT OF S.E. ENGLAND. 



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tain altitude on the outward slopes of the South Downs. Thus, Dr. 

 Mantell had observed them at Copperas Gap, a short distance inland 

 of Shoreham. I have also to thank the same author for informing 

 me that many years ago Mr. Hennah discovered the bones of Elephant 

 and Stag in one of the cavities of the chalk towards the higher por- 

 tion of the Downs, and there also mixed up with fractured flints and 

 stiff ochreous clay. This fact is of value in enabling us to identify 

 the breccia of Brighton and Kemp Town cliffs with much at least of 

 the wide-spread debris which lies at higher levels on the slopes of the 

 South Downs. 



At the western end of Brighton, near the shore, the drift differs 

 somewhat both in its matrix and position from what has been de- 

 scribed east of Kemp Town. Patches and coverings of angular chalk - 

 flints are also to be seen, but the chalk is nowhere visible, except in 

 excavations, and even the bottom or shingle-bed has only been reached 

 near the sea. In the low tract between Brunswick Terrace and 

 Hove, an unstratified angular-flint-breccia, of from 8 to 10 feet in 

 thickness, being removed, beds of reddish-brown clay, occasionally 

 mottled, and in the lower part blue, resting upon sands, have been 

 cut into to a depth of nearly 30 feet, for the manufacture of bricks. 

 On a first inspection, geologists might doubt whether these were 

 really strata of the age of the Plastic and London clays in situ, so 

 completely is the mineral character identical ; whilst their eroded 

 upper surface, on which the chief mass of the flint-breccia is placed, 

 would seem to separate the two deposits. But both these signs are 

 fallacious ; for in the very heart of these clays and sands I found frag- 

 ments of Mytilus edulis and other sea-shells of existing species with 

 their colours preserved, and among them three or four perfect specimens 

 of Littorina littoralis, — a shell whose form and strength enabled it to 

 withstand violence. And although masses of coarse breccia, similar 

 to that which overlies, are not visible beneath, still thin and irregular 

 layers of finely and sharply fractured flints occur here and there in 

 the clays, with small fragments also of chalk. In following these 

 brick- earth clays to Shoreham, they are found to rest (where wells 

 have been sunk) on a coarse flint-rubble*. 



It thus follows, that this detrital deposit of Brighton, however di- 

 versified in aspect, and whether it be called Combe Rock, Elephant 

 Bed, or Brick Earth, pertains to one and the same group, and is refer- 

 able to so very modern a geological era, that the sea-shells now living 

 then prevailed, although the great land-animals which also then lived 

 have long ceased to inhabit our country. The presence of the sea- 

 shells in this coast-portion of the drift is, I believe, solely due to the 

 broken materials having been washed down into a nook or depression 

 then occupied by the sea. At higher levels they are never found. 



Those of my geological friends who have hitherto considered this 

 coarse breccia to have been formed somewhat in the same manner as 

 a sea-beach, must therefore excuse rne when I differ from them in 



* Fossil bones of quadrupeds have recently been found low down in this brick- 

 earth of Hove and Shoreham, associated with broken sea-shells of existing species. 



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