146 AGRICULTURE 



on the other phosphatic and nitrogenous 

 manures just mentioned. 



Steamed bone flour generally contains 

 about 60 per cent, of phosphates and Ij per 

 cent, of nitrogen, and, utilizing unit values 

 as above, the price per ton works out 

 at 4, 12s 6d., a price, however, that is 

 distinctly below the market rate. 



In the case of dissolved bones, a greater 

 or less percentage of the phosphate has been 

 rendered soluble by the use of sulphuric 

 acid, and converted into the same " soluble 

 phosphate 5: as that in superphosphate of 

 lime. Assuming that the dissolved bones 

 contain 15 per cent, of soluble and 20 per 

 cent, of insoluble phosphates, together with 

 3 per cent, of nitrogen, we can value the 

 soluble phosphate at Is. lOd. the unit- 

 value already applied to superphosphate of 

 lime and the insoluble phosphate at Is. 3d. 

 the unit-value for basic slag while the 

 nitrogen may be valued at 11s. 8d., as in 

 sulphate of ammonia. Using these figures 

 we arrive at a total price per ton of 4, 7s. 6d., 

 a figure, however, which is lower than that 

 at which pure dissolved bones can generally 

 be purchased. As a matter of fact the 

 unit-values of the constituents of dissolved 

 bones are more likely to be 2s. 9d. for the 



