494 ON THE SUCCESSIVE FORMS 



case a subdivision of the primary strata will become 

 necessary. A second elevation of the strata raised these 

 above the waters, and thus was produced the third 

 state of the Earth. 



This third world is preserved for our inspection. 

 Those which were once its only strata, are now our 

 primary ones ; and they furnished the materials for 

 those new rocks which appear in the fourth state of 

 the globe, and which were raised above the ocean by 

 a third revolution. 



By that revolution was formed the fourth world ; 

 the greater part of which still remains, forming the 

 foundation of our own, however modified by numerous 

 subsequent changes. This world included our primary, 

 and the earlier, or lower portions of our secondary 

 strata, producing, during its continuance, the coal de- 

 posits ; but the revolution which it underwent to a 

 fifth state, though probably not of a different nature 

 from the former, exhibits, to us, the marks of de- 

 pression only, without any proofs of elevation. The 

 new dry land became sea ; and the lands formerly ele- 

 vated, were, to a certain degree, or extent, lowered. 



Thus was produced a fifth world. How far it dif- 

 fered from the preceding we cannot discover, because 

 we are not certain that the last or fourth revolution 

 was an extensive one, and do not know what might 

 have remained, and what might have been elevated. 

 It is possible that it may have resembled the third, 

 that none but primary rocks formed the dry land: 

 but it is equally possible that both the primary and 

 secondary might have united to form it. 



The sixth world is that v/hich we inhabit. It is the 

 produce of a fifth revolution in the globe. To form 

 it, the depressed strata were again elevated; whatever 

 else might have occurred. Thus it contains, together 

 with its own new ones, the strata of the three preceding 



