CHAPTER IV 



THE PLACING OF SOIL MATERIAL (Continued) 

 II. GLACIAL OR ICE-LAID DEPOSITS 



THE glaciers and ice sheets of former times covered extensive 

 areas with deposits of material that may be divided into morainal, 

 intermorainal, drunilins, kames, and eskers. During the glacial 

 period, practically all of North America north of the Ohio and 

 Missouri Rivers, amounting to 4,000,000 square miles, was covered 

 with an ice sheet (Fig. 32) that had gradually pushed southward 



Fia. 32. Front of Chenega Glacier compared with Washington Monument, 550 feet high. 



(Lawrence Martin.) 



"" ' ; 7 

 . v " 



S5fe._- ;,j 



~* 



.,* "<*f.-.*'--v'-;! 



Fio. 33. Very stony and gravelly phase of glacial drift near Whitewater, Wisconsin 



(King.) 



41 



