Bone Manures 



Bone Meals and Bone Dust without undergoing 

 any further treatment. Their relative values depend 

 upon the fineness with which they are ground. We 

 have quoted elsewhere the analysis of badly ground 

 bones given as manure and found twenty years 

 afterwards without having suffered any change or 

 yielded any of their fertilising matter. Honestly, 

 they are of very little value as manure ; also they 

 are much adulterated with neutral materials such 

 as sand, bricks, cinders, etc. 



The Bone ]\Ieals obtained from the East Indies 

 and the River Plate are of about the same value 

 as the home production. 



Steamed Bone Flour. — In steamed bone flour 

 the bones have been treated with steam, partially 

 extracting the nitrogenous organic matter for the 

 purpose of making glue. The bones, themselves very 

 brittle, are reduced to an exceedingly fine powder. 

 As a rule they contain more phosphates than green 

 bones, sometimes from 60 per cent, to 70 per cent, 

 and less nitrogenous organic matter, of which there 

 is about I per cent. They are better worth buying 

 by the unit than bone meal, because there is less 

 demand for them ; nevertheless, they are a better 

 manure. 



Fermented Bones. — Sometimes pounded bones 

 are fermented. For this purpose they are put into 

 a heap where they heat, and from time to time horse 

 urine is poured over them. After some weeks they 

 become disintegrated. A good deal of nitrogen has 

 been lost during the heating and fermenting pro- 

 cesses, but the phosphates have become more 

 assimilable. 



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