UTILIZATION OF BONES. 107 



To get bones into an available form for manuring 



garden and field crops, there are a variety of ways 



open to us. The simplest of these is 



m^rof Bones", burning. Of course, this process de- 

 prives the bones of their organic (ni- 

 trogenous) matter, so that in the ash of bones we 

 have nothing left but their mineral constituents, 

 chiefly phosphate of lime, with perhaps a trace of 

 potash ; but this plant food is in a condition which 

 fits it for use, more or less immediate, by plants. 

 My own favorite way (burning in the heap of rub- 

 bish) has already been fully described in Fourteenth 

 Chapter. Bones burned in a furnace or stove where 

 wood is used for fuel add largely to tiie value of the 

 wood ashes as a fertilizer, by adding their own 

 phosphoric acid to that already there, and to the 

 rich store of potash. 



Another way in which we can make bones avail- 

 able for plant food is by mixing them, after having 

 been broken into small pieces by grinding or pound- 

 ing, with fresh horse manure, and piling this up to 

 come to a lively fermentation. This treatment 

 softens them. It saves all their elements of plant 

 food, and is a good way for the average farmer. 



A third way of making bones available for manure 

 is by exposure to the chemical action of unleached 

 wood ashes. They should be broken up as finely as 

 possible, and put in alternate layers with the ashes 

 in a barrel or hogshead, packed down quite solid, 

 in a similar way as you would set a leach. Then 

 pour on water or still better the rich liquid dipped 

 up from the barnyard until the whole mass is 

 moistened clear down to the bottom. Leave in this 

 condition, occasionally putting on a little more 

 water to keep the mass moist all the time, until the 



