FIFTH CHAPTER. 



NITROGEN, ITS NATURE AND EFFECT. 



a CO NEAR and yet so far"— that is what the soil 

 ^ worker might truly say of nitrogen, which 

 to him is the most important, as it is the most ex- 

 pensive to procure, of all fertilizing substances. For 

 while it exists in vast and unlimited quantities, 

 surrounding our whole world in a layer many miles 

 in thickness, and forming such a large part of our 

 atmosphere that tons and tons of it are resting upon 

 each acre of ground, it is at the same time exceedingly 

 shy and modest — a blushing, bashful maiden among 

 the elements. It can only be won after hard woo- 

 ing, and it finds only few acceptable suitors among 

 its "set." It refuses to be absorbed into plant 

 structure in its single state, except in a very small 

 way when dissolved in water (this ab- 

 Eiementary sorbs only a little more than one per 

 Not AvaUabie. ^^^^ ^^ i^^ bulk), and can be induced 

 to enter plant tissue only after having 

 formed a chemical union with a congenial mate or 

 element. While the farmer need not worry about 

 a source of supply, so far as oxygen and hydrogen 

 are concerned, and usually but little so far as carbon 



