PEEFATORY I^OTE. 



A LARGE portion of the facts peitainiug to the lakes of North America, 

 ])reseiited in this Ijook, were gleaned by the writer during thirteen years' 

 geological work for the National Government, and are recorded principal- 

 ly in the publications of the U. S. Geological Survey. The facilities for 

 exploration afforded by my connection with Government surveys enabled 

 me to visit various parts of the United States, inclusive of Alaska, and to 

 observe many phases in the topographical development of our continent. 



The publications of the U. S. Geological Survey, and of several State 

 surveys, also contain the records of observations by others, relating to 

 the subject here treated, which have been freely used. It is hoped that 

 this popular presentation of a small part of the results of the various 

 surveys referred to will serve to direct attention to the rich and varied 

 store of information contained in the reports of mj colleagues and fellow- 

 workers. 



Besides the publications of official surveys, many papers relating to 

 the subject here discussed have appeared in journals, proceedings of 

 scientific societies, etc., to which references may be found in footnotes in 

 this volume. 



The origin of lake basins and tlie history of the great cycles in the 



development of the relief of tlie land to which they pertain, have been 



discuss»tl especially by Professor W. ^I. Davis, of Harvard University. 



Professor Davis has also read the manuscript of this book and kindly 



given me the benefit of his criticisms and suggestions. 



I. ('. \l. 



