OP A FORMER WORLD. 47 



ous origin, but also to have been deposited in succession, 

 The same rock, or its equivalent, in other parts of the 

 world, would be deposited during or about the same period ; 

 but this was not the case with rocks whose positions in the 

 scale were apart from each other. To illustrate this : The 

 British chalk beds, and their foreign equivalents, were de- 

 posited during the same period ; but the upper chalk, and 

 the London clay, were deposited in succession. 



That this long series of rocks occupied numerous ages 

 in accumulating, is obvious, first, from the fact, that many 

 of them are of enormous thickness. Secondly, each group 

 required for its perfection, at least two (in many instances 

 a greater number) changes of land and water. Now judg- 

 ing from the operations of nature in the historic period, we 

 may conclude that these changes were gradual ; and if grad- 

 ual indeed many of the rocks bear internal evidence to the 

 fact who can reckon the time consumed in their forma- 

 tion? 



The second argument in favor of the antiquity of the 

 globe, is drawn from the nature of the strata, or their min- 

 eralogical character. Under this argument we do not in- 

 clude those rocks that are composed, to any extent, of or- 

 ganic remains ; their proper place is in connection with the 

 next. The rocks of which we now speak, namely, the coarse 

 and fine sandstones the beds of shale, marl, clay, slates, 

 &c., are composed of older rocks. Let us take the old red 

 sandstone as an example. The conglomerate, so largely de- 

 veloped in this system, is not a rock composed of new ma- 

 terials ; the geologist recognises the pebbles of which it is 

 almost entirely made up, as belonging to rocks lower in the 

 series. And the finer beds that accompany and overlie the 

 conglomerate, are obviously, in many instances, composed of 

 the same material ground into small particles. These illus- 

 trations apply to the whole class of rocks of which we are now 

 treating. The material of which they are composed, whether 



