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of cereals, as wheat, barley, rice, &c., or the seeds of 

 leguminous plants, we find a great difference between 

 their ashes and those which 'remain after the 

 combustion of other parts of the plant, such as 

 stalks or leaves. The ashes of the latter invariably 

 contain a large proportion of the carbonates of 

 the alkalis and alkaline earths, and consequently 

 effervesce with acids, while the fresh ashes of seeds 

 will not effervesce. On closer chemical examina- 

 tion, we find that these ashes consist of alka- 

 line phosphates which are soluble in water, and 

 of the phosphates of lime and magnesia, with a 

 little iron, which are insoluble . 



Phosphoric acid forms fully 50 per cent, of the 

 ashes of all the edible grains ; and an idea of its 

 importance can be formed when it is known that it 

 has been demonstrated by practical experiments 

 that not a grain of corn can be formed in its ab- 

 sence, and that, as a natural consequence, the quality 

 and quantity of the seed will stand in proportion 

 to the available store of this plant-food. 



Now, it is a well-known fact that phosphoric acid 

 is one of those substances the restoration of which to 

 the fields has been totally neglected in India. For 

 centuries it has been withdrawn from the soil, it 

 must be in thousands of tons ; the grains con- 

 taining it have served as food for millions of human 

 beings and animals, but the restoration of this 

 most essential requisite for all our grain crops has 



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