at Pounceford, in Sussex, 603 



of the land itself, or by subsidence in the level of the ocean, 

 has long been matter of the most fiery dispute amongst geo- 

 logists, many of whom suppose that the chalk, though not the 

 slightest vestige of it is found in the alluvium of the hills and 

 valleys of the central and forest ridge of the Wealden, formerly 

 " covered the whole space in which the inferior strata are 

 now exposed." This assumption Conybeare pronounces " to 

 be highly rash," " though," adds he, " the truncated form 

 of its escarpment evidently shows it to have once extended 

 much further than at present." ( Outlines of Geology of England 

 and Wales, p. 144.) Lyell, however, in his beautiful Prin- 

 ciples of Geology, — a work pronounced by men of all parties 

 (for among geologists, to their shame be it spoken, party 

 spirit runs as high as amongst politicians) to be the most elo- 

 quent, comprehensive, and truly philosophical outline of the 

 science ever published in the English or any language, — adopts 

 this theory to its full extent; observing, that, though he never 

 traversed " the wide space which separates the North and 

 South Downs, without desiring to escape from the conclusions 

 expressed as to the original continuity of the upper secondary 

 formations over the anticlinal axis of the Weald, yet he was 

 invariably brought back again to the opinion that the chalk 

 was originally continuous, on a more deliberate review of the 

 whole phenomena." (p. 190.) The hypothesis, however, pro- 

 posed by the reviewer of Ly ell's work in the Quarterly, 

 appears to me so far more probable and intelligible, that I 

 insert it below, lis a conclusion to this imperfect sketch. It, 

 at all events, does away with a great deal of theoretical reason- 

 ing, never very interesting to beginners, and has simplicity, if 

 nothing else, to recommend it. I think it right, however, to 

 premise, that both Mr. Bakewell [Introduction to Geology, 

 p. 291.) and De La Beche [Manual of Geology, p. 307.)? high 

 authorities on such a subject, appear to coincide with Mr, 

 Lyell's views. 



" Why is it necessary to suppose the chalk to have at any 

 time extended over this part of Europe? Why are we not 

 at liberty to suppose that the Weald clay and Hastings sands 

 had been elevated above the sea before the deposition of the 

 chalk, and formed a ridgy island in that sea? These latter 

 beds must have been formed above the sea level, since they 

 contain only organic remains of land and freshwater animals 

 and plants. If it must be admitted that they subsequently 

 sunk in some degree, so as to allow the marine formation of 

 the green-saud to overlap their edges, at least it is not neces- 

 sary to suppose such an amount of subsidence as would have 

 clothed their whole surface with the entire thickness of the 



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