

': ''.: 



PREFACE. 



The three papers here presented form but portions of a single 

 investigation systematically planned to throw new light upon 

 important problems in soil management, and the full signifi- 

 cance of them,, as parts of a whole, can only be seen by consid- 

 ering them in connection with the three papers from which 

 they have been severed in that they were not allowed to appear 

 as Departmental publications. 



It is believed that the subjects of the six papers, and the data 

 presented in them, merit adequate discussion but this was with- 

 held to avoid, as far as possible, antagonizing the published 

 views of the Bureau and the three papers are presented here as 

 they were originally submitted. 



In addition to these statements it is due the writer and his 

 associates in this investigation to say that the data presented 

 have lost very much of fullness and value through changes in 

 plan, made in. the midst of the investigation but over which we 

 had no control. 



F. H. KIXG. 



Madison, Wis., Aug. 18, 1901. 



