HISTOEICAL GEOLOGY 73 



inclination. He also conceived the idea of urging a more thor- 

 ough survey of his own State ; hence he resigned his commission 

 and returned home. The effort for a resurvey of Massachusetts 

 was successful, and he was recommissioned to do the work. The 

 results appeared in 1841 and 1844." 



Oliver P. Hubbard was assistant to Silliman in 1831- 

 1836, and then up to 1866 taught chemistry, mineralogy, 

 and geology at Dartmouth College. James G. Percival 

 was graduated at Yale in 1815, and in 1835 he and C. U. 

 Shepard of Amherst College were appointed state geol- 

 ogists of Connecticut. Their report was issued in 1842. 



James Dwight Dana (1813-1895) was undoubtedly the 

 ablest of all of Silliman 's students. Graduated at Yale 

 in 1833, he spent fifteen months in the United States 

 Navy as instructor in mathematics, cruising off France, 

 Italy, Greece, and Turkey. In 1836 he was assistant to 

 Silliman, and in 1837, at the age of twenty-four years, 

 he published his widely used System of Mineralogy. 

 Two years later Dana joined the Wilkes Exploring Expe- 

 dition as mineralogist, returning to America in 1842 ; his 

 geological results of this expedition were published in 

 1849. In 1863, during the Bebellion, he published his 

 Manual of Geology, and through four editions it 

 remained for forty years the standard text-book for 

 American geologists. 



First American Geological Society. The founding in 

 1807 of the Geological Society of London, the parent of 

 geological societies, undoubtedly had its stimulating 

 effect on Silliman, and with his marked organizing ability 

 he began to think of forming an American society of the 

 same kind. This he brought about the year following 

 the appearance of the Journal, that is, in 1819. The 

 American Geological Society, begun in 1819 (1, 442, 

 1819), was terminated in 1830 (17, 202, 1830). The first 

 meeting (September 6, 1819) and all the subsequent ones 

 were held in the cabinet of Yale College. The brief 

 records of the doings of this society are printed in vol- 

 umes 1, 10, 15, and 18 of the Journal. Silliman was the 

 attraction at the meetings, surrounded by his mineral 

 cabinet, and he gave "the true scientific dress to all the 

 naked mineralogical subjects" discussed. 



