THE IOW AN DRIFT 



589 



thinnest. The dry upland slopes above the level of the peat, as 

 well as the dry slopes below that level, are liberally sprinkled with 

 Iowan bowlders imbedded in loam and clay and ranging up to more 

 than 12 feet in diameter. These bowlders are in themselves ade- 

 quate evidence of a glacial invasion at a time subsequent to the 

 gravel-forming phase, for they were not transported and deposited 

 by either wind or water. 



Fig. 4. — View looking north from the margin of the Doris pit, showing the young, 

 uneroded, bowlder-strewn Iowan drift plain; a very typical view in the area occupied 

 by this young drift. 



Typical examples of mound springs, easily accessible from 

 Charles Gity, and showing the stratigraphic relations of Kansan, 

 Buchanan, and Iowan deposits, occur on both sides of the railway 

 in the north half of Section 2, Township 95, Range 15. Preliminary 

 to laying a water pipe from the springy belt to the barn on the land 

 of Mr. W. E. Waller, south of the railway, a shallow well was dug 

 on the dry ground just above the peat; and this passed through 

 the cover of Iowan bowlder-bearing loam and clay, and through 

 the thinned edge of the rusty gravels, down far enough to make a 

 water-tight basin in the blue Kansan. A deeper well near the 

 barn, with 12 feet of gravel and 60 feet of blue clay, may be cited 



