462 Analyses of Books. [Dec. 



to account for the seeming anomaly from some changes which have 

 taken place in the position of these rocks in consequence of a 

 catastrophe posterior to their formation. They are not more 

 extraordinary than the nature and position of some of the floetz 

 rocks described by Mr. Webster in the Isle of Wight. Such 

 rare deviations ought not to be considered as overturning the 

 general order which the rocks follow with respect to their order. 



Werner's transition rocks certainly are entitled to attention in 

 consequence of their very peculiar nature. His arrangement, 

 whether accurate or not, has been attended with the advantage 

 of calling the attention of geologists to these rocks. We find 

 them always grouped together. They sometimes contain fossil 

 remains of animals and vegetables, and sometimes not. In the 

 former case, as far as my own observations go, they are asso- 

 ciated with floetz rocks ; in the latter case, with primitive rocks. 

 Grey wacke, which constitutes the most striking and characte- 

 ristic of the transition rocks, differs a good deal in its appearance, 

 and I have been for some time of opinion that two distinct 

 rocks have been confounded together under the same name. I 

 believe that a greywacke exists to which the epithet primitive 

 may be applied, as it never contains fossils, or alternates with 

 rocks that contain fossils ; while there is another variety that 

 associates with floetz rocks, and contains fossils. It alone is 

 entitled to the epithet transition, or floetz, if our author chooses 

 to discard the term transition altogether. 



I agree with our author that Werner's term transition implies 

 an absurdity. Werner, or his pupils (I know not which), 

 attempted a great deal too much when they undertook to detail 

 the order of the formation of all the rocks constituting the crust 

 of the earth. Indeed their repeated inundations and retreats of 

 the waters may be considered as perfectly on a par with Burnet's 

 account of the antediluvian world, and the effects of the deluge. 

 All we know about the rocks composing the crust of the earth 

 is, that some are destitute of fossils, while others contain them. 

 The first are original rocks, about the formation of which it 

 seems folly to speculate. The second set must have been formed 

 after the earth was inhabited by animals and vegetables ; though, 

 as human remains have not been observed in them, probably 

 before the existence of man. Unless we suppose, as has been 

 done, that the secondary rocks were formed by a deluge, and 

 that after this deluge, sea and dry land changed places ; so that 

 the antediluvians and all their works were buried under the 

 bottom of our present ocean. The secondary rocks are formed 

 of the debris of the primitive, ard lie over them, except in some 

 rare cases, to be accounted for by earthquakes or other similar 

 catastrophes. To suppose a set of rocks formed while the 

 earth was passing from a state of not being capable of support- 

 ing animals and vegetables to a state capable of supporting them 

 is, to saytheleastof it, a most whimsical and unhkely supposition. 



