1887.] 439 [Upham. 



entire distance. Considered in a broad view, this central part of 

 the state may be described as a low plateau, elevated a few hun- 

 dred feet above lake Superior on the east and the Red river valley 

 on the west. In most portions it is only slightly undulating or 

 rolling, but these smooth tracts alternate with belts of knolly and 

 hilly drift, the recessional moraines of the ice-sheet, which com- 

 monly rise 50 to 100 feet, and in the Leaf Hills 100 to 350 feet, 

 above the adjoining country. The bed-rocks are nearly every- 

 where concealed by the drift-deposits, into which the streams have 

 not eroded deep valleys, their work of this kind being mostly lim- 

 ited to the removal of .part of their glacial flood-plains. The up- 

 per portions of the Mississippi and of its chief tributaries, and all 

 the smaller streams throughout this region, flow in many places 

 through lakes which they have not yet filled with silt nor drained 

 by cutting down their outlets. At Little Falls the glacial flood- 

 plain of the Mississippi is about three miles wide, reaching two 

 miles east, and one mile west from the river. Its elevation is 25 

 to 30 feet above the river at the head of the rapids, which have a 

 descent of seven feet. The Mississippi here flows over an outcrop 

 of Huronian slate, and the same formation is also exposed by the 

 Little Elk river near its mouth, on the west side of the Mississippi 

 three miles north of Little Falls. Veins of white quartz occur in 

 the slate at both these localities, and were doubtless the source of 

 that used by man here in the glacial period for the manufacture of 

 his quartz implements. 



The locality and section of the modified drift, where these worked 

 fragments of quartz were found by Miss Babbitt, and the account 

 of their discovery, are best told in her own words from her paper 

 read before the anthropological section of the American Associa- 

 tion for the Advancement of Science at its Minneapolis meeting 

 in 1883. I quote as follows : 



"Rudely worked quartzes had previously been discovered here by the 

 state geologist of Minnesota, Prof. N. H. Winchell, by whom they had 

 been described and figured in the state geological report lor 1877. . . 



. . The find reported by Prof. Winchell consists of chipped objects 

 of a class generally ascribed to what is called the rude stone age. Of 

 these many appear to be mere refuse, while others are regarded as finished 

 and unfinished implements. The Winchell specimens have been assigned, 

 upon geological ground, to a prehistoric era antedating that of the mound- 

 building races, and reaching back to a time when the drift material of 

 the terrace-plain was just receiving its final superficial deposit. It is 



