VIU PREFACE. 



agricultural chemistry ; these are, " Praktische 

 Diingerlehre," and ^'Lantlwirthschaftliche Fiitter- 

 ungslehre." 



The best English work on agricultural chemistry 

 exists as yet only in detached papers. The 

 numerous reports containing the Eothamsted in- 

 vestigations on the chemistry of crops and 

 animals will be found chiefly in the Journal of 

 the Eoyal Agricultural Society. 



R. W. 



May, 1881. 



