HISTORICAL SKETCH. 99 



1864, Whittleiey.] 



at Winkelmann's, near New Ulm, with the gypsiferous deposits in the valley 

 of the Des Moines. 



9. Regards the Coteau des Prairies as made by a broad synclinal in 

 the quartzyte outcropping at Redstone, and illustrates it by a diagram.* 



CHARLES WHITTLESEY IN NORTHERN MINNESOTA. 



Mr. Whittlesey, who had been employed on the survey of Dr. Owen, made 

 further examinations in the state for private parties in 1859 and 1864, and his 

 geological notes, with illustrations, were printed at Cleveland. Ohio, in 1866, 

 by order of the legislature of Minnesota. This little pamphlet contains much 

 information concerning the northern part of the state, not to be found in 

 any earlier publication. His ascent of the Big Fork river was made in com- 

 pany with Dr. Norwood, when engaged on the survey of Dr. Owen, in Sep- 

 tember, 1848, and his description of that stream has but little that is not 

 found in the report of Norwood. 



Mr. Whittlesey was the first to make observations on the drift-deposits 

 under the guide of any adequate conception or theory of their origin. Dr. 

 Owen's survey ignored this subject entirely, or incidentally grouped the 

 phenomena under the head of "agricultural capabilities'',! while Mr. Eames 

 was too much engaged in a mineral hunt to give them any consideration, 

 except as impediments to "prospecting." Whittlesey's grouping of "glacial 

 etchings" proves the direction of the glacial movement in the northern part 

 of the state to have been from the northeast, and he unhesitatingly ascribes 

 all the phenomena in North America to the agency of glaciers, placing the 

 southern limit of the movement in New Jersey, northern Pennsylvania, 

 Ohio, Indiana, Illinois, Wisconsin and lowa.J The correctness of this 

 early prognostication has been strikingly J verified by late explorations in 

 several of the states named. He could see no reason to suppose that any 

 changes of level of the country have taken place since the era of the drift. 



*Jt is singular that this theoretical explanation of the Coteau should have been incorporated on the late geological 

 map of the United States, by Profs. Hitchcock and Blake, accompanying the ninth trailed States census report, rather 

 than the positive statements of all other observers who have crossed it, to the effect that no rocky outcrops are to be 

 found If the Huronian rocks underlie the Coteau, they would certainly appear at the surface at a great many places. 

 Prof. Hind visited this ridge near the 49th parallel ; so did Dr. Owen ; Mr. Featherstonhaugh had described it; Keating 

 had given us information concerning it ; Nicollet'g opinions were on record. These all testify that it is made up of drift. 

 Probably the basis rock is Cretaceous, as that formation appears on both sides in the adjoining streams. The examina- 

 tions of the survey have established the "erratic" nature of the whole range. Compare KvUeiins of the Minnesota Acad 

 my. Vol. I. p. 100. 



tCompare Owen's description of the "southern confines of the Coteau." Introduction, pp. ixxv. and zixvi. 



{Compare Fresh-water glacial drift of the Northwatem slates. Smithsonian Corttribttliom, May, 1864. 



