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on the Atlantic coast. The only alluvial rocks that 

 are found in this district, are those of sand stone, 

 which are evidently the results of an alluvial forma- 

 tion. 



In alluvial deposites, in almost every country, are 

 likewise found, immense quantities of animal remains, 

 though in a state very different from those which are 

 found in secondary formations. 



I have remarked, that secondary formations are, ge- 

 nerally, the results of a natural operation, or in other 

 words, they are natural deposites from water, proba- 

 bly, in a state of perfect tranquillity. And that allu- 

 vial formations are the results of accidental operations ; 

 for in almost all instances, they are amassed and form- 

 ed by the operations of currents, which have been pro- 

 duced by natural or accidental causes. 



I have also remarked that a great difference exists, 

 not only in their texture and composition, but in the 

 process of their formation. 



This is so striking, that while it constitutes a dis- 

 tinctive characteristick between the two formations, it 

 affords an interesting subject of inquiry, as to the prin- 

 ciples, by which secondary and alluvial rocks, and the 

 animal and vegetable substances therein contained, 

 were solidified ; and also, the difference of time requir- 

 ed in their productions. 



It is, I believe, a prevailing opinion with many, that 

 almost all secondary rocks, as well as those of the pri- 

 mitive kind, must have required a long and tedious 

 process in their formation, by precipitations, crystali- 



