240 



THE GEOLOGIST. 



the European new red sandstone. The elevation of the 

 chief part of the great belt of metamorphic rocks on the 

 S.E. side of the chain is referred to the same great move- 

 ment. In conclusion, the authors remark that an incompa- 

 rably greater change in the physical geography of North 

 America, and perhaps of the globe, seems to have occurred 

 at the close of the Carboniferous epoch than at any previous 

 or subsequent period ; and they consider these changes, and 

 the effect produced by them on the organic world, as afford- 

 ing some of the highest subjects of geological investigation. 



Mr. Murchison confirmed the views given by the authors 

 of the paper, of the great break in the series of geological 

 deposits which occurs between the Palaeozoic rocks and 

 later deposits 5 the coincidence in the direction of some 

 great chains in Europe and America, belonging to the same 

 geological period, was very striking. He was not prepared 

 to give any opinion upon Professor Rogers' undulatory 

 theory. 



Sir H. T. De la Beche described the general character of 

 anticlinal and synclinal lines, and stated, that whilst con- 

 tortions of the strata sometimes assumed the character of 

 mountain chains, at other times they occupied large tracts 

 of low ground, as in the comparatively flat country of South 

 Wales. He then made some observations on the space 

 occupied by masses of rock over certain areas ; the older 

 rocks of England, {{flattened, would occupy a much greater 

 space than at present ; and the area of the Alps and Jura 

 would be greatly extended if all their contortions were 

 spread out. The phenomena described in the Appalachian 

 chain, so far as small differences in the direction of the 

 anticlinals were concerned, did not at all aflfect the brilliant 

 theory proposed by M. Elie de Beaumont ; the object of the 

 geologist was to trace the correspondence in the direction 

 of the great lines of elevation, and in this broad view the 



