THE 



AMERICAN 



JOURNAL OF SCIENCE AND ARTS. 



[SECOND SERIES.] 



Akt. XXIV. — On American Geological History: — Address be- 

 fore the American Association for the Advancement of Sci- 

 ence, August, 1855, by James D. Dana. 



[In republishing this address, the author has added various 

 notes in illustration of the text. The circumstances of the occa- 

 sion on which it was delivered precluded the introduction of 

 detailed explanations. Moreover, as the author aimed to give 

 the history of principles or the grander steps of progress in 

 American geology, rather than a full exhibition of its successive 

 discoveries, he unavoidably omitted the mention of many names 

 which are honorably associated with the science in this country. 

 Both obligations to others as well as himself and the science, have 

 therefore prompted the introduction of the notes. 



New Haven, September 10, 1856.] 



****** * 



In selecting a topic for this occasion, I have not been without 

 perplexity. Before an Association for the Advancement of 

 Science, — science in its wide range, — a discourse on the progress 

 of science in America for the past year would seem legitimate. 

 Yet it is a fact that the original memoirs in most departments, 

 published within that period, would make a very meagre list. 

 Moreover, it is too much to expect of any one to roam over others' k 

 territories, lest he ignorantly gather for you noxious weeds. I 

 have, therefore, chosen to confine myself to a single topic, that 



SECOND SERIES, VOL. XXII, NO. 66. NOV., 1866. 



39 



