172 G. 0. Smith — Government Geological Surveys. 



national, political, and economic considerations led nat- 

 urally to the demand for a more exact knowledge of the 

 vast national domain in the "West. Geography and geol- 

 ogy are so closely related that Mr. Emmons's distinction 

 of the two periods is useful only with the limitations 

 inferentially set by himself — namely, that while geologic 

 investigation entered into most of the explorations of the 

 earlier period, the geologist was regarded as only an 

 accessory in these exploring expeditions; on the other 

 hand, in the later surveys the topographic work was 

 developed because it was essential to the geologic 

 investigations. 



The year 1818 was a notable one in American geology, 

 first of all in the appearance of the American Journal of 

 Science, itself so perfect a vehicle for geological thought 

 that, as is so well stated by Dr. G. P. Merrill, "a perusal 

 of the numbers from the date of issue down to the present 

 time will alone afford a fair idea of the gradual progress 

 of American geology.' ' The beginning of publications 

 on New England geology appeared that year in Edward 

 Hitchcock's first paper on the Connecticut Valley (1, 105, 

 1818) and the Danas' (S. L. and J. F.) detailed geologic 

 and mineralogic description of Boston and vicinity; and 

 the " Index" of Amos Eaton (noticed in this Journal, 1, 

 69) was the first of that long list of notable contributions 

 to American stratigraphy that are to be credited to the 

 New York geologists. 



In the present discussion, too, the year 1918 can be 

 regarded as in a way the centennial of Government geo- 

 logic surveys, for it was in 1818 that Henry R. School- 

 craft began his trip to the Mississippi Valley — perhaps 

 the first geologic reconnaissance into the West — and it 

 was his work in the lead region which served to make him 

 a member of the Cass expedition sent out by the Secre- 

 tary of War in 1820 to examine the metallic wealth of the 

 Lake Superior region. The earlier Government explora- 

 tions of Lewis and Clark, in 1803-7, and of Pike, in 1805-7, 

 were so exclusively geographic that geologic work under 

 Federal auspices must be regarded as beginning with 

 Schoolcraft and with Edwin James, the geologist of the 

 expedition of Major Long in 1819-20 to the Rocky Moun- 

 tains. Both these observers published reports that are 

 valuable as contributions to the knowledge of little- 

 known regions. 



