135 



the greatest effect on stiff, clayey, or marshy soils. The 

 permanent improvement of the soil effected by lime, and 

 its effects upon different crops. The action of lime on soil 

 and plant. 



THE importance of phosphoric acid as an essen- 

 tial and predominating constituent in the seed of all 

 our grain crops, has' been jamply discussed in pre- 

 vious pages, and will doubtless be fully recognized. 

 Any substance which contains this mineral acid in 

 appreciable quantities, must, therefore, be consi- 

 dered a most valuable manure, and specially adapted 

 for India's soil, which, by the existing system of 

 agriculture, has lost more of this constituent than 

 of any other. 



Bones, the frame -work of human beings as well 

 as of animals, are the chief source of phosphoric 

 acid available to the agriculturist. Their com- 

 position varies within certain limits, but the 

 following table given by Dr. Thomson represents a 

 fair average constitution : 



Heum of a Heum of Vertebrae of 



Sheep. an Ox. a Haddock. 



Organic Matter 43-3 48'5 39'5 



Phosphate of Lime 60'6 45'2 56' 1 



Carbonate of Lime 4'5 6'1 3'6 



Magnesia 0*9 0'2 0'8 



Soda 0-3 0-2 0'8 



Potash 0-2 0-1 0-8 



99-8 100-3 100-8 



The great value of bones, then, as powerful 

 fertilizers is evident from the above, and their use 



