OF THE EARTH. 493 



ceding views have unavoidably given a still more in- 

 tricate appearance to that which is an intricate subject 

 in itself, it will be convenient to the reader if I com- 

 mence these remarks with a brief summary of the con- 

 ditions of the earth which I have attempted to establish. 

 The first condition which I have inferred, was that 

 which furnished, from its rocks, the clay, sand, and 

 mica of the fragments imbedded in our primary strata, 

 because these belong to a preceding set of strata. Of 

 this Earth we can have no other visible evidence, as 

 there can be none at all for an Earth before it : and I 

 have therefore taken it as the first, though a prior one 

 might be supposed, on the obvious supposition that 

 these materials must have arisen from rocks still an- 

 terior, under similar circumstances. 



The first revolution also of which we have any evi- 

 dence, is that which elevated the materials contained 

 by the first ocean to form the rocks of a second world. 

 Of this second world, we see the fragments of the 

 strata, preserved in the conglomerates of the present 

 primary rocks, together with fragments of the granite 

 by which these were probably elevated. It is not un- 

 likely, that the very strata themselves form part of 

 our primary ones, since this can scarcely fail to be the 

 case, for the obvious reason that they could not have 

 all been destroyed, and must have been re-elevated 

 together with them at the subsequent revolution. The 

 distinction ought to consist in nonconformity of order 

 among, the present primary strata, which should thus 

 display at least two divisions. But geologists having 

 never imagined such a state of things, having never 

 yet reasoned in this very obvious manner, have never 

 sought for such distinctions. I think that I can quote 

 cases : but am averse to do it while I remain unsup- 

 ported by others : hereafter, I doubt not that it will be 

 fully established ; now that the fact is indicated and 

 the road to the investigation pointed out : in which 



