FACTS AND INFERENCES. 295 



the bed of the ocean; from whence, at a future era, they will rise in a 

 stratified form, constituting new continents and islands. Against 

 these notions, a host of objections might be started ; but it is sufficient 

 to remark, that the peculiar character and vast thickness of some of 

 our strata, particularly the chalk and the oolite, preclude the possi- 

 bility of their having been formed by such a process. The sea receives 

 from the waste of the land, quantities of mud, sand, gravel, &c. ; 

 which it deposits in thin layers, partly on its shores, and partly in 

 the deeper parts of its bed ; but these thin layers bear no proportion 

 to the massive strata of our rocks. To produce such a series of strata 

 as exists in our district, in the way supposed, a long succession of 

 ages would be reqviisite ; and, during some of these ages, the rivers 

 behoved to send into the sea nothing but sand ; during others, nothing 

 but mud or clay; during others, nothing but materials for oolite; 

 and during others, nothing but chalky matter. One of the most 

 learned of the authors alluded to, has stated, that it would require at 

 least a century, to waste away the surface of the land to the depth 

 of one foot, and deposit it in the bottom of the ocean.* Now, if we 

 estimate the chalk strata at three hundred feet in thickness, it would 

 require, at this rate, thirty thoxisancl years, to form the chalk strata 

 only ; even supposing the ancient sea to be of no greater extent than 

 the dry land : and during this immense period, the rivers behoved to 

 convey into the ocean, where these beds were forming, nothing but 

 materials for chalk and tlint!!! It is clear, that our strata must 

 have been produced by very different means, and deposited on a far 

 grander scale. 



14. Some of the strata abound with organic remains, others 



contain few or none; and this diversity is not according to the order 



of their succession. — The beds that contain most organic remains, 



viz. the oolite and the alum shale, are neither the highest nor the 



* Playfair's Illustrations, p. 424, Note. 



