OF THE EARTH. 489 



actually visible, it remains to mention that revolution 

 by which they were brought to their present places. 

 Before this event, we must still suppose that the dry 

 land consisted of the primary and of a portion of the 

 inferior secondary strata only ; as it had done before 

 the elevation of that portion of the secondary strata 

 on which the terrestrial, or coal strata, were deposited. 

 By this great, and, to us, most important catastrophe, 

 the whole face of the earth must have been completely 

 changed ; far more, we may presume, than by any 

 preceding one. 



It is evident that it must have involved the whole of 

 the strata, of whatever class, from the earliest to the 

 latest of the globe. As the latest portion of the secon- 

 dary strata, then reposing in a horizontal position be- 

 neath the ocean, were raised to the surface, and in- 

 clined in the manner that we now find them, so every 

 inferior series in order, however previously inclined 

 or disturbed by former revolutions, must have again 

 been moved. Thus, even the primary strata, which 

 had been twice elevated, and, in some places at least, 

 once depressed, possibly oftener, must have been a 

 third time raised, together with all those of successive 

 ages which they bore on their surface. Thus also the 

 inferior secondary strata were a second time brought 

 up to the light of day ; and thus the coal deposits 

 were restored to those regions in which they had been 

 originally formed. However subsequently modified 

 by more recent partial revolutions, and by those ac- 

 tions of waste and deposition which are now passing 

 before our eyes, it was by this important revolution 

 that the present distribution of the surface was deter- 

 mined, in the general outline of our continents and 

 islands, the chains of mountains which give rise to our 

 rivers, and the cavities which received our lakes. 



