J 



20 Feather s!on}iaugh''s Geological Report. 



and its members are deemed to have been deposited at an epoch 

 peculiar to themselves, and separated from any other epoch 

 by a period of time of some duration. If the existing surface 

 of the earth should at any future era be entombed, with the 

 zoological and botanical bodies constituting the present order 

 of nature, by new sedimentary deposites brought there, as the 

 existing ones apparently have been, and a new order of things 

 were to commence consequent to the repose after such an 

 event, having some affinities for the preceding one, yet pos- 

 sessing organic bodies not belonging to it, such sedimentary 

 deposites would, according to the received language in geolo- 

 gy, be called a new formation. This hypothetical state of 

 things is thought to have been often repeated in the ancient 

 state of the planet. It is proper also to remaik^ that, although 

 the members of this column preserve an invariable succession 

 to each other, yet it frequently happens that, in various parts 

 of the world, many of them are wanting. These deficiencies in 

 the localities, where they are observed, are to be attributed 

 either to the inaction of the causes to which the beds owe 

 their origin, or to other causes, through the agency of which 

 they have disappeared. Sometimes, indeed, the deficiency is 

 only apparent, the strata being so much altered in appearance 

 from the contiguity of intrusive rocks, as to assume another 

 character. Wherever any of the strata are found, however, 

 the order of their succession is constant, like the alphabetic 

 order of letters, B in America being never found above A, 

 whilst A in China, or in any other part of the world, is always 

 found above all the other letters, and never under any of 

 them. The intrusive rocks are of course excluded from this 

 statement. Where A (and the same may be said of any other 

 letter) is found contiguously overlying G, or any other bed, 

 in such instances the intervening beds are deficient, from 

 some of the causes before alluded to. 



By such inductive steps are we awakened to a sense of 

 those truths which geology teaches, and come to perceive 

 that the general arrangement of the beds composing the su- 



