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IOWA ACADEMY OF SCIENCE 
Figure 2. — Map showing the parallel, vertical walls of the Mississippi river, 
and the normally developed salients and sinuosities of the Turkey river. 
Figure 3. — View below McGregor, Iowa, showing sloughs and low islands 
occupying the greater part of the flat bottom of the Mississippi gorge, with the 
vertical, rocky cliffs of the Wisconsin side dimly seen in the distance. 
