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THE WONDERS OF GEOLOGY. Lect. VIII. 



We now advance another stage in our eventful progress ; 

 and again we have to investigate deposits that have been 

 accumulating for innumerable ages in the profound depths 

 of seas fed, by rivers and streams charged with the detritus 

 of the countries over which they flowed, and imbedding the 

 remains of the plants and animals that existed at the period 

 of their formation. Again we shall find new forms of ex- 

 istence presented to our notice, differing from, but bearing an 

 analogy to the inhabitants of the waters which deposited the 

 marine strata of the most ancient beds previously examined, 

 yet altogether dissimilar from those of modern eras. In 

 vain may we seek for the remains of the mammalia of the 

 Tertiary periods, — of the mollusca, fishes, and reptiles of the 

 Chalk — of the colossal oviparous quadrupeds of the country 

 of the Iguanodon — of the dragon-forms of the Oolite — of 

 the fish-like lizards of the Lias — or of the tropical forests 

 of the Carboniferous system — all have disappeared ; and as 

 the traveller who ascends to the regions of eternal snow, 

 gradually loses sight of the abodes of man, and of the 

 groves and forests, till he arrives at sterile plains, where a 

 few stunted shrubs alone meet his eye ; and as he advances, 

 even these are lost, and mosses and lichens remain the only 

 vestiges of organic life ; and these too at length pass away, 

 and he enters the confines of the inorganic kingdom of 

 nature: — in like manner the geologist who penetrates the 

 secret recesses of the globe, perceives at every step of his 

 progress the existing types of animals and vegetables gra- 

 dually disappear, while the relics of other creations teem 

 around him; these in their turn vanish from his sight — 

 other new and strange niodiiications of organic structure 

 supply their place — these also fade away — traces of animal 

 and vegetable life become less and less manifest, till they 

 altogether disappear — and he descends to the primary rocks, 

 where all evidence of organization is lost, and the granite, 

 like a pall thrown over the relics of a former world, con- 



