AMERICAN 



Journal uf Science anlr ^tts. 



[THIRD SERIES.] 



Art. I. — On the Quaternary, or Post-tertiary, of the New Raven 

 Region; by James D. Dana.* 



I. The Glacial bea an era of Glaciers, and not of Icebergs. 



Agassiz and Guyot, who were long among the most active of 

 Alpine explorers, found on their arrival in New England only 

 the effects of glaciers. But American geologists are still divi- 

 ded in opinion, and some of the most eminent have pronounced 

 in favor of icebergs. 



The region of New Haven is exceedingly well situated for 

 settling the question, not only as regards its immediate vicinity, 

 but for the whole interior of New England. For in the first 

 place, the region is a wide and open area at the southern termi- 

 nation of the Connecticut Valley ; f and this valley is the great 

 central valley of New England, includmg the larger part of its 

 surface outside of Maine, the Green Mountains making its west- 

 ern border, and the White Mountains and the height of land 

 southward, its eastern. Then secondly, the valley has a north- 



* The principal facts relating to the New Ffaven Quaternary, which I propose to 

 bring out in the article here begun, are included in a paper by the author on the 

 Geology of the New Haven region, published recently 1 



(ILoft 



f The Connecticut Valley has a general course from north to south, varying 

 little from S. 9° W. It is occupied by the Triassic (or Triassico-Jurassic) Red 

 sandstone formation from New Haven to northern Massachusetts, and this indicates 

 the position which it had in the Mesozoic era. The Connecticut river leaves the 

 valley at Middletown, taking there a 

 rocks of the eastern half of Connect 



