CHAPTER V. 



OF THE MUTUAL ACTION OF THE ORGANIC AND INORGANIC 

 ELEMENTS OF SOIL. 



128. In agriculture, little and seemingly unimportant dis- 

 coveries are valuable. Nothing is to be despised, which 

 may lead to a rational and true theory of agriculture ; this 

 only can lead to successful practice. Practice, founded on 

 sound principles, can be taught only by a knowledge of the 

 manner how the elements of soil affect each other, and veg- 

 etation. This knowledge cannot be obtained without the 

 application of theoretical opinions. The opinions of merely 

 scientific men, may be wholly theoretical ; but what is 

 science 1 



It is, -says Davy, " refined common sense, the substitution 

 of rational practice, for unsound prejudice." 



In no department of human industry is there so great a 

 demand for the union of theory and practice, as in agricul- 

 ture. The book farmer and the practical farmer, must now 

 shake hands. They have been too long wrestling, and trying 

 to get each other down, at arm's length, and now grappling 

 in side hug, they find the closer the embrace, the longer 

 they stand. So it should be ; theory and practice should 

 mutually support each other. 



129. The theoretical and the practical farmer aim at one 

 common object. The latter is employing certain means to 

 effect certain ends ; the former unfolds the laws of nature, 



(101) 



