THE NEW FERTILIZATION. 107 



and makes composts and plows under green growth and buys 

 commercial fertilizers. He knows that four-fifths of the at- 

 mosphere which submerges his fields is pure nitrogen, but 

 he knows also that his plants can no more live upon this nitro- 

 gen than a man could quench his thirst from the waters which 

 surrounded him if he were in the midst of the sea. With 

 suitable apparatus, by distillation, purification, etc., this water 

 might be made drinkable, but it could not be used in the state 

 in which it first presented itself. And the plant, though sur- 

 rounded by such an immense quantity of the very element 



CHAPTER III., FIG. 26. ONE HUNDRED BUSHELS OF CORN TO THE ACRE IN 



PENNSYLVANIA. 



which is essential to its life, will die unless this element has 

 been put through a process which will convert it into avaiU 

 able plant food. Once the nitrogen has been worked over 

 by the subtle chemistry of Nature, the growing plant feeds 

 upon it with avidity and thrives luxuriantly; but nitrogen in 

 its native state as we find it in the atmosphere is practically 

 valueless to vegetation. On this account great quantities of 

 nitrogenous material nitrogen in combination manures, 

 composts, and fertilizers of various kinds are annually hauled 

 to the fields and deposited upon them. The nitrate deposits 

 of distant parts, as the guano beds of Chili, have been ex- 



