of an 1fce 



found inside of this line and between two flows 

 are called "medial" moraines. There is a 

 subdivision called " kettle " or " gravel " mo- 

 raines, which are very prominent in northern 

 Illinois and southern Wisconsin, and may be 

 said to culminate in the vicinity of Madison. 

 This moraine is a great deposit of gravelly 

 soil. Where this moraine exists the face of 

 the country is covered with " kettle holes " of 

 all sizes and shapes, and in some of them there 

 are small lakes, while others are dry. The 

 great chain of inland lakes that are found in 

 southern Wisconsin and northern Illinois were 

 formed by deposits of ice that had been cov- 

 ered by glacial drift, gravel and otherwise, 

 brought down and deposited upon these masses 

 of ice which gradually melted away, leaving a 

 depression at the points where they lay, while 

 the drift that was piled around them loomed 

 up and became the shores of the lake. This is 

 substantially Dr. Wright's theory, who studied 

 the formation of these " kettle holes " at the 

 mouth of the Muir glacier. This enthusiastic 

 glacialist has spent many summers tracing the 

 terminal moraine with its fringe along the 

 lines heretofore indicated. He is, therefore, 

 entitled to speak with authority on matters of 

 glacial action. 



The part of the country that has been 

 plowed over by these glaciers is called the gla- 

 ciated area and the rest the unglaciated. The 



