54 



THE ILLINOIS GLACIAL LOBE. 



changes to a blue till within a few feet. A large amount of wood was 

 in the blue till near the bottom of the well, at a depth of 25 to 30 feet. 

 The wood, however, is incorporated in the till in the same manner as 

 bowlders or pebbles, and does not indicate a soil horizon. The well appar- 

 ently terminated in the Illinoian drift. 



On the plain east of this ridge a black soil (Yarmouth), which separates 

 the Illinoian sheet from the underlying drift, has been noted in wells at the 

 following depths : 



Depth to black soil ( Yarmouth) in wells on the plain near Denmark, Iowa. 



C. A. Flohrer, sec. 10, T. 69, R. 5 W 



W. Hawkins, see. 13, T. 69, E. 5 W 



E. Newton, sec. 24, T. 69, E. 5 W 



C. H. Burton estate, sec. 25, T. 69, E. 5 W 

 Thomas Saunderson, sec. 35. T. 69, E. 5 W 



Benj. Krehbiel, sec. 36, T. 69, E. 5 W 



Mr. Holstein, sec. 30, T. 69, E. 4 W 



S. Van Tnyl estate, sec. 30, T. 69, E. 4 W. 



O. B. Brackett, Denmark 



James C'onaro, Denmark 



William Blackinton, Denmark 



Dr. William Sloat, Denmark 



Public well. Denmark 



Feet. 

 725 

 715 

 725 

 720 

 720 

 720 

 725 

 715 

 700 

 700 

 700 

 700 

 700 



Feet. 

 30-32 

 16-20 

 35-40 

 30-35 

 20-22 

 35-40 

 45-48 

 35-37 

 20-26 

 19-24 

 26 



The wells at Mr. Flohrer's and Mr. Hawkins's pass through several feet 

 of ash-gray clay, apparently a subsoil, immediately below the black soil. 

 Exposures on ravines in this part of the county sustain this interpretation 

 of soil and subsoil. The Van Tuyl well has the folio wing' series of beds: 



Section in icell on 8. Van Tuyl estate, near Denmark, Iowa. 



Feet. 



Yellow silt or loess, slightly calcareous and containing a few small pebbles near base (Iowan) 7 



Brownish-yellow clay, with few pebbles and but slightly calcareous (Illinoian") 10 



Brownish-yellow till, pebbly and calcareous (Illinoian) 8 



Blue clay, with few pebbles (Illinoian) 10 



Black mucky soil, with wood (Yarmouth) 2 



Brownish-yellow till (Kansan) J9 



Hard blue till (Kansan) 6 



Limestone 4 



Total 59 



