LIST OF ILLUSTRATIONS 



Page 

 Optical Principle of Ultra Microscope 43 



A Small Anticline in a Post-Glacial Valley Insert 96-97 



A Fold in Portage Flaggs in Lake Cliff Insert 96-97 



A Fault Showing Brecciated Zone, with Upturned Beds Insert 98-99 



An Asymmetrical Fold Deforming the Surface of Forty-Foot 



Terrace Insert 98-99 



Map Showing by Oblique Lines the Area of Main Loess Distribution 



in Illinois 103 



Map of Canton Quadrangle, Fulton Co., Illinois, Showing Slopes 



of Illinois Drift Surface at Time Loess was Laid Down Upon It 111 



Moraine-like Hills of Loess Bordering Iowan Drift Margin in Tama 



County, Iowa Insert 100-101 



Bluff of Loess along Mississippi River in Calhoun County, Illinois 



Insert 112-113 



Thermostat for Heating Seeds 134 



