548 



REPORT OF NATIONAL MUSEUM, 1904. 



by county maps, though no geological map of the State in its entirety 

 was furnished. A colored section across the State from Greencastle 

 to Terre Haute accompanied the report for 1869. 



Cox was assisted during the entire or a part of the time b} r Frank H. 

 Bradley, Rufus Haymond, G. M. Levette, B. C. Hobbs, R. B. Warder, 

 W.*W. Borden, M. N. Elrod, John Collett, and E. S. 

 fndiana? r i869-i879. Mclntire, the fossil flora being described by Leo Les- 

 quereux and the fauna of Wyandotte Cave by E. D. 

 Cope. Zoological and botanical subjects were treated by D. S. Jordan, 

 J. M. Coulter, and J. Schenk. 



These reports as a whole contained little new or impressive. In the 

 eighth, which was the most comprehensive thus far issued, Cox him- 

 self culled attention to the fact that the geological history of the State 

 "appears tame and devoid of the marvelous interest which attaches to 

 many other regions, and that there is not a single true fault or upward 



or downward break or displacement of the 

 strata thus far discovered.'"' The oldest 

 rocks of the State were found in the south- 

 ern portion, extending from the Ohio River 

 near the mouth of Fourteen Mile Creek to 

 the eastern boundary line. These are the 

 so-called Hudson River rocks of Hall, which 

 Cox correlated with SaU'orcl's Nashville 

 group, and which Worthen and Meek had 

 included under the name of Cincinnati 

 group. He regarded the Silurian strata as 

 uplifted, not by a local disturbance, but " by 

 an elevating force that acted very slowly 

 and extending over the entire central area 

 of the United States. " The seat of greatest 

 force, he thought, however, was not limited to southwestern Ohio, 

 but was to be looked for in Kentucl^y. 



Cox accepted the general theory of glacial drift as at present under- 

 stood, and conceived that the climatic changes might be due to the 

 relative position of land and water, possibly a change in the course of 

 the Gulf Stream. He could find no evidence of a subsidence of the 

 land to terminate the glacial period, nor could he find in Ohio, Indi- 

 ana, or Illinois anything to militate against the commencement of a 

 glacial period in Tertiary times and its continuation — 

 until brought to a close by its own erosive force, aided by atmospheric and meteoro- 

 logical conditions. By these combined agencies acting through time the mountain 

 home of the glacier was cut down and a general leveling of the land took place. 



This suggestion that the glacial epoch worked out its own destruc- 

 tion through a process of leveling, whereby the altitudes which gave 

 it birth were so far reduced that glaciers could no longer exist, is 

 unique and, so far as the present writer is aware, original with Cox. 



Fig. 83. — Edward 'flavors Cox. 



