56 MANURES I 



Relative Manurial Value of Different Manures. 



Average of several authorities. 



Nitrogen in ammonium sulphate, guano, etc. 100 



Do. sodium nitrate ... 98 



Do. fish guano, meat meal, etc. ... 81 



Do. bone meal, horn meal, etc. ... 77 



Do. farm-yard manure 56 



Phosphoric acid in superphosphate 100 



Do. guano 92 



Do. bone meal ... 88 



Do. medium meal 64 



Do. coarse meal 40 



Do. basic slag 33 



Do. farm-yard manure 33 



Potash in sulphate ... .. 100 



Do. chloride (muriate) 82 



Nitrogen, phosphoric acid, and potash are the only three sub- 

 stances which require to be applied in ordinary manuring and 

 most manures are valuable only in proportion to the amounts 

 of these they contain ; while manurial experiments usually 

 resolve themselves into testing the effect of the various com- 

 mercial compounds and mixtures of these three bodies on 

 different soils. The other mineral foods required by plants 

 exist in superabundance in the great majority of soils. 



Amount of 

 Nitrogen (N) 



Do! 



Do. 

 Ammonia (NH 8 ) 



Do. 



Do. 



Do. 



Do. 

 Potash (anhydrous) 



Useful Factors. 



Multiplied Gives corresponding 



by 



Do. 

 Do. 

 Do. 



(K 2 0). 



1-214 



4-714 



6-25 



6-071 



0-824 



3822 



3-147 



3-706 



5-0 



1-85 



1-585 

 2-149 

 7-4 



amount of 



Ammonia. 



Ammonium sulphate. 

 Albuminoid matter. 

 Sodium nitrate. 

 Nitrogen. 



Ammonium sulphate. 

 Do. chloride. 



Nitric acid. 

 Sodium nitrate. 

 Potassium sulphate. 



Do. 



Do. 



Kainit. 



chloride, 

 nitrate. 



