author's preface. xi 



to gather harvests from it for future generations, but even 

 to permit the present to share in its benefits. 



Then would Germany follow the example of England, 

 by encouraging and supporting chemical investigations on 

 agricultural subjects, by erecting chemical laboratories to 

 meet the present demands of this profession, and by estab- 

 lishing chemical councils and lecturers for agricultural as- 

 sociations, etc., etc. May Germany soon follow England 

 in these wise steps for the support and prosperity of her 

 agriculture ! 



The subjects I have treated of in these Lectures are here 

 offered to the public, at the repeated request of many of my 

 hearers. I cannot help feeling strongly, however, how diffi- 

 cult it i3 to communicate in print the interest excited by 

 word of mouth, and how much more incomplete this en- 

 deavor must be in a science which requires experiments for 

 its elucidation, the full description of which would lead 

 too far from my real object. But this cannot be helped. 

 To be plain and intelligible to the non^chemical agricul- 

 turist is my chief aim. 



The chemist by profession will perhaps find many repe- 

 titions, which I have made in order to be clear, — many 

 expressions unscientific or trivial, which to me seem pop- 

 ular and simple. 



All these and many other objections will not disturb me, 

 if only the agriculturist does not complain that the Lectures 

 are too theoretical, too learned, or unintelligible. If the 

 h 



