The Chemistry of Garden Crops 



the mineral substances in the soil and renders them available as 

 plant food. When vegetable refuse is burned, the nitrogen one of 

 the costliest constituents is dissipated and lost. But by burying 

 the refuse the soil gets back a proportion of the organic nitrogen it 

 surrendered and something over in the way of soluble phosphatic 

 and potassic salts ; and as this organic nitrogen assumes ultimately 

 the form of nitric acid, it can be assimilated by the growing plant, to 

 the great benefit of whatever crop may occupy the ground. 



The practical conclusion is, that in the treatment of the soil a 

 skilful gardener will endeavour to promote its fertility by affording 

 the natural influences of rain, frost and sun full opportunity of libe- 

 rating the constituents that are locked up in the staple ; by restoring 

 in the form of refuse as much as possible of what the soil has parted 

 with in vegetation ; and by the addition of such fertilising agents as 

 are adapted to rectify the natural deficiencies of the soil. Thus, 

 instead of following a process of exhaustion, the resources of the 

 garden may be annually augmented. 



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