AND FRESH-WATER FORMATIONS. 333 



thing depends. The mysteries have been created by 

 Geologists who had formed no conception of such a 

 cause, and who had never extended their Geology 

 beyond the upper strata and their remains ; disturbing 

 alike themselves and their readers, by vague notions 

 which they could not even express, and tormenting 

 themselves with their own visions. 



