﻿MURCHISON — FLINT DRIFT OF S.E. ENGLAND. 



397 



Station, Kemp Town. This fact, which proves 

 that the coast-line underwent an oscillation 

 of 40 feet at so recent a period, in a space 

 of two miles, will, it seems to me, account 

 satisfactorily for the tumultuous accumula- 

 tions which followed, and particularly for 

 the sudden transport of the angular flint-drift 

 above the beach so affected ; the overlying 

 blue clay, yellow clay or brick-earth, and 

 the heaps of flint being all, according to my 

 view, parts of the drift which were succes- 

 sively accumulated along the shore, in one 

 and the same period, which terminated with 

 great violence. 



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VOL. VII. PART I. 



Another new feature of interest has been 

 added to the descriptive geology of the en- 

 virons of Brighton by a recent excavation 

 for brick-earth on the north side of Furze 

 Hill (Wick), which proves that this spot of 

 high ground, the property of Baron de Gold- 

 smid, to which the western part of the town 

 is now extending, is composed of Plastic-clay 

 in situ, and not of the re-aggregated drift- 

 clay just described, which so prevails in the 

 flat grounds along the Sussex coast. I had 

 doubts on this point (see p. 367), and they 

 have been removed by visiting the new cut- 

 s' c3 tings accompanied by Mr. JohnCarrickMoore 

 and Mr. D. Sharpe. From 15 to 20 feet of 

 mottled plastic-clay with courses (one of 

 which is 3 feet thick) of black bituminous 

 earth, in parts a lignite, have been clearly ex- 

 posed. This clay differs essentially from the 

 drift-clay that has been derived from it, in 

 containing no fragments of flint or chalk, 

 and is therefore of superior value for the 

 manufacture of bricks. It contains yellow 

 decomposing iron-pyrites, which gives origin 

 to a mineral water, having the same acrid 

 taste as that of Alum Bay in the Isle of 

 1 1 Wight ; and there is little doubt that the 

 1 u Ba adjacent saline chalybeate of Wick owes its 

 chief properties to the same stratum. Nu- 

 merous openings of the surface for the 

 foundations of new houses, around this hill 

 of plastic-clay, expose either the chalk with 

 flints, or that rock covered by a few feet of 

 re-aggregated stiff loam with some coarse 

 unrolled flints mixed up in it. This mass 

 of Flastic-clay is, therefore, as complete an 



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