MANURES. 1C9 



In the foregoing remarks on the subject of mineral 

 manures, I have endeavored to point out such a 

 course as would result in the "greatest good to tin- 

 greatest number," and consequently, have neglected 

 much which might discourage the farmer with tin- 

 idea, that the whole system of scientific agriculture 

 is too expensive for his adoption. Still, while I have 

 confined my remarks to the more simple improve- 

 ments on the present system of management, I 

 would say briefly, that no manuring can 1 xtridly 

 economical that is not based on a knowledge of the re- 

 quirements of the soil and of the crops t and of the 

 best means of supplying them, together with t/<c most 

 m.-i'itpuloua care of every ounce qf evaporating <>r sol- 

 'tille manure made on the farm, and a return of the 

 earthy matters sold off in produce. 



CHAPTER X. 



ATMOSPHERIC FERTILIZERS. 



IT is not common to regard the gases in the at- 

 mosphere in the light of manures, but they are the 

 most important manures we have, as they are the 

 original source of more than nine-tenths of the entire 

 production of our fields. Indeed, they are almost the 

 only organic manure ever received by the uncultiva- 

 ted parts of the earth, as well as by a large portion of 



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