The Physiography of the Region of Chicago (Fryxell)

The Physiography of the Region of Chicago (Chicago: University of Chicago press, c1927), by Fritiof Fryxell, contrib. by University of Chicago Local Community Research Committee and Chicago Commonwealth Club (stable link)
New Online Books
http://onlinebooks.library.upenn.edu/webbin/book//lookupid?key=olbp68719