TOMPKINS COUNTY. 299 



in the dip of the rock, so that it must cover the whole of the south portion of the county. In 

 an economical point of view, the question of the Ithaca and Chemimg groups involves no con- 

 sequences of any importance whatsoever. Their interest is as regards classification, which 

 forms, as it were, the fulcrum to the lever of the human mind ; and the more firmly the 

 former is planted, the more steady are the operations of the latter, and the higher will be its 

 achievements. 



