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and lastly, that the whole region was again sunk under the waters of 

 a deep ocean, in which were deposited the great formations of green- 

 sand and chalk. Continuing in the same spirit of induction, we might 

 add — that these marine deposits again became dry land, upon which 

 lived great tribes of palaeotherian animals, now become extinct — 

 that during this period were formed the lacustrine rocks of Hamp- 

 shire and of the Isle of Wight — that it was succeeded by a sudden 

 and violent convulsion, heaving on their edges the great deposits of 

 the Isles of Wight and Purbeck, and at the same time producing the 

 anticlinal axis and great longitudinal fractures, so well described in 

 this memoir. 



There can be no doubt that the same cause which upset the Isle of 

 Wight, also produced the great breaks and fissures of the Weymouth 

 district 5 and that this upheaving force (for such we must consider 

 it) came into action at a recent geological period, is proved by 

 the vertically of the lower lacustrine beds at the east end of the Isle 

 of Wight. Whether this period was contemporaneous with the last 

 elevation of the Eastern Alps may well admit of doubt : to substan- 

 tiate a fact like this, many links are yet wanting in the chain of evi- 

 dence; and England has, if I mistake not, been acted upon by far too 

 many local disturbing forces, to be ever brought rigidly within the 

 systems of the great European chains considered in the researches 

 of M. Elie de Beaumont. 



The investigation of the faults and dislocations interrupting the 

 continuity of our secondary deposits is becoming, daily, a sub- 

 ject of increasing importance ; and we are now called upon, not 

 to regard them as solitary phsenomena, but to trace them through 

 whole regions, and to examine their relations to each other. These 

 great theoretical and practical questions throw no common difficul- 

 ties in the way of a person who is beginning the study of Geology : 

 and it is especially on this account, that I regard the " Sections 

 and Views illustrative of Geological Phsenomena," recently published 

 by Mr. de la Beche, as a compendium, excellently fitted to assist the 

 progress of our science. 



Before finally quitting the subject of British secondary formations, 

 I must mention a communication by Mr. Sharpe, describing a speci- 

 men of an Ichthyosaurus found in the lias near Stratford-upon-Avon. 

 From the proportions of the vertebree, the size of the paddle, and 

 the circular or oval form of its component bones, as well as from 

 other anatomical peculiarities, the author concludes, that this ani- 

 mal belongs to a new species, for which he proposes the name of 

 Ichthyosaurus grandipes. 



Facts illustrating the structure of distant regions of the earth 

 have their value greatly enhanced by the difficulty of obtaining 

 them. Every gleaning of information on the physical history of Aus- 

 tralia or the Isles of the Pacific, will be received in this Society with 

 the deepest interest. I will not, however, detain you with any ana- 

 lysis of the paper by Mr. Cunningham on the Geology of Hunter's 

 River in New South Wales, or of that by Mr. Caldcleugh on the 



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