22 



Phenomena in various parts of America, As 

 Geology had, in a manner, grown out of Mi- 

 neralogy, it was to be expected that the or- 

 der and arrangement of rocks and mountain 

 masses should have almost exclusively oc- 

 cupied our attention. Hence the nature 

 and extent of that portion of the globe, con- 

 sisting of loose sand and gravel, or what is 

 technically called alluvion, has been much 

 neglected. Hitherto these had been consi- 

 dered as occasioned solely by deposits from 

 the ocean and rivers, and much ingenuity has 

 been exercised to explain many appearances 

 which could scarcely have depended on such 

 comparatively trifling causes. The attention 

 of Mr. Hayden was long since directed to 

 the vastness of this formation in the United 

 States, and as early as 1817, he commenced 

 a personal examination of this immense de- 

 posit, which extends over twenty degrees 

 of longitude. In his endeavours to account 

 for its origin, he has satisfactorily separated 

 it from the alluvial, distinguished it by the 

 epithet ternary^ and is entitled to the merit of 

 having anticipated the important distinction 

 recently established by the European geolo- 

 gists, in regard to this formation. In con- 



