138 



trying it. But both bone-dust and superphos- 

 phate are now prepared in Bombay by the Western 

 India Chemical Works Company, and can be obtain- 

 ed from them, I believe, at Es. 60 per ton for 

 bone-dust and Es. 80 for superphosphate. 



Another source of phosphoric acid is available to 

 the Indian agriculturist, namely, the deposits of 

 fossil-bones, the remains of bygone animal genera- 

 tions, which have been discovered in several parts of 

 India. These coprolites, as they are termed, contain 

 a vast store of phosphoric acid, and will become 

 very important in course of time when their agricul- 

 tural value will be duly recognized. 



Fossil-bones, even when finely divided, are 

 very little acted upon by the usual solvents of 

 earthy phosphates, and therefore require to be 

 converted into Superphosphate before being applied 

 to the land. 



It has been shown that the chief mineral plant 

 constituent lost by the soil of India has been 

 phosphoric acid. The system of manuring with 

 the ashes of grass, straw, leaves, and similar matter, 

 has always restored to the soil a small quantity of 

 potash, lime, silica, and magnesia ; but the store of 

 phosphoric acid has been continuously reduced year 

 by year,partly by the total non-utilization of human 

 refuse, partly by the custom of using dried dung 

 as fuel a practice which has for centuries deprived 

 the soil of one of its most legitimate manures. 



