IN THE MUD OF THE LEVANT. 7 



may be compared to crystallization, but is of a 

 coarser nature, and essentially different from it."* 



Thus we are manifestly approximating to the 

 early conceptions of Linnseus and Buffon, who, if 

 the above views are correct, were not far in error 

 in the general principle which they advocated, viz., 

 the organic origin of limestone rocks, — though 

 they were completely in the dark as to the facts 

 by which the correctness of their hypothesis was 

 to be ultimately tested and proved. 



In most geological questions, we are only safe 

 in our generalizations, so long as we test our 

 explanation of the phenomena presented in the 

 crust of the globe, by the eflFects of active agencies 

 now operating upon its surface. Fuschel laid the 

 foundation of a glorious truth when he declared, 

 that " the earth has always presented phenomena 

 similar to those of the present day."f It is a vital 

 error to regard the world as having been the theatre 

 of agencies which have long since ceased to act. 

 Overwhelmedbythe evidences ofmighty forces and 

 indefinite periods, we are in danger of forgetting 



* Observations on the Organic Composition of Chalk and 

 Chalk Marl.— Mag. Natural History, 1841, p. 305. 

 f Delabeches's Geol. Manual, p. 193. 



