Bone Manures 



Generally there is no need to fear this loss. Super- 

 phosphate is the phosphate manure for catch crops. 

 The quantities manufactured annually show that 

 it is in general use. It ought to be used more 

 often than mineral phosphates and compound 

 manures, which still occupy too important a place. 

 For the value of phosphoric acid the unit type is 

 that of superphosphates. 



Bone Manures. 



Bone manures are thought more of in England 

 than in any other country. They have been in 

 use a long time, and are sold in every conceivable 

 form ; merely more or less finely broken, fermented, 

 steamed, distilled, incinerated, transformed into 

 superphosphates, with their own phosphates pre- 

 cipitated, and so on. Because of the great demand 

 for them their price is quite high enough, higher 

 perhaps than is justified by the quantity and quality 

 of their fertilising elements. In fact, seeing that 

 products of higher value and cheaper price per unit 

 are now on the market, they ought not to occupy 

 the position they have held so long. 



Providing they have not undergone any chemical 

 transformation, bones form a slow manure, the 

 effect of which is felt for many years, one, more- 

 over, which is not subjected to any loss. 



When they first came into use they were rouglily 

 ground, without any cleaning ; later on they were 

 ground more finely and eventually they were fer- 

 mented by putting them into heaps and watering 

 them with urine, in order that the nitrogenous 

 organic matter they contained should be made 



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