PREFACE TO THE FIRST EDITION. 



The wide interest manifested in my treatise upon The 

 Ice Age in North America and its Bearing upon the An- 

 tiquity of Man (of which a third edition was issued a year 

 ago), seemed to indicate the desirability of providing for 

 the public a smaller volume discussing the broader ques- 

 tion of man's entire relation to the Glacial period in Eu- 

 rope as well as in America. When the demand for such 

 a volume became evident, I set about preparing for the 

 task by spending, first, a season in special study of the 

 lava-beds of the Pacific coast, whose relations to the Gla- 

 cial period and to man's antiquity are of such great in- 

 terest ; and, secondly, a summer in Europe, to enable me 

 to compare the facts bearing upon the subject on both 

 continents. 



Of course, the chapters of the present volume relating 

 to America cover much of the same ground gone over in 

 the previous treatise ; but the matter has been entirely re- 

 written and very much condensed, so as to give due pro- 

 portions to all parts of the subject. It will interest some 

 to know that most of the new material in this volume was 

 first wrought over in my second course of Lowell Institute 

 Lectures, given in Boston during the month of March 

 last. 



I am under great obligations to Mr. Charles Francis 

 Adams for his aid in prosecuting investigations upon the 

 Pacific coast of America ; and also to Dr. H. W. Crosskey, 



