PART I. CHAPTER V. 



01 



Land has been raised, not the sea lowered. 



CHAPTER V. 



ELEVATION OF STRATA ABOVE THE SEA — HORIZONTAL AND INCLINED ♦ 

 STRATIFICATION. 



Why the elevated position of marine strata should be referred to the rising up 

 of the land, not to the going down of the sea — Upheaval of extensive masses of 

 horizontal strata — Inclined and vertical stratification — Anticlinal and synclinal 

 lines — Examples of bent strata in east of Scotland — Theory of folding by lateral 

 movement — Dip and strike — Structure of the Jura's»-Rocks broken by flexure — 

 Inverted position of disturbed strata — Unconformable stratification — Fractures 

 of strata — Polished surfaces — Faults — Appearance of repeated alternations pro- 

 duced by them — Origin of great faults. 



Land has been raised, not the sea lowered. — It has been 

 already stated that the aqueous rocks contaiaing marine fossils 

 extend over wide continental tracts, and are seen in mountain 

 chains, rising to great heights above the level of the sea. Hence 

 it follows that what is now dry land was once under water. But 

 if we admit this conclusion, we must imagine either that there has 

 been a general lowering of the waters of the ocean, or that the 

 solid rocks, once covered by water, have been raised up bodily 

 out of the sea, and have thus become dry land. The earlier 

 geologists, finding themselves reduced to this alternative, em- 

 braced the former opinion, assuming that the ocean was origin- 

 ally universal, and had gradually sunk down to its actual level, 

 so that the present islands and continents were left dry. It 

 seemed to them far easier to conceive that the water had gone 

 down, than that solid land had risen upwards into its present 

 position. It was, however, impossible to invent any satisfactory 

 hypothesis to explain the disappearance of so enormous a body 

 of water throughout the globe, it being necessary to infer that 

 the ocean had once stood at whatever height marine shells were 

 detected. It moreover appeared clear, as the science of Geology 

 advanced, that certain spaces on the globe had been alternately 

 sea, then land, then estuary, then sea again, and, lastly, once 

 more habitable land, having remained in each of these states for 

 considerable periods. In order to account for such phenomena, 

 without admitting any movement of the land itself, we are 

 required to imagine several retreats and returns of the ocean ; 

 and even then our theory applies merely to cases where the 

 marine strata composing the dry land are horizontal, leaving 



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