VI PREFACE 



It has not been thought necessary to cite authorities on 

 which the statements in the text are based. For these and 

 for more complete discussions of most of the matters treated 

 in this book, teachers and others who may wish to pursue 

 the subject further are referred to the college text on soils 

 by Lyon, Fippin and Buckman. 



The author is especially indebted to Dr. H. O. Buckman 

 for much assistance and advice. He has contributed prac- 

 tically all of the laboratory exercises. 



Ithaca, N. Y., 

 June 1, 1917. 



