2O6 THE FIRST BOOK OF FARMING 



fertilizer buyers in testing the values of the brands 

 offered them on the markets. 



In the following list are given the " trade values 

 agreed upon by the Experiment Stations of Massa- 

 chusetts, Rhode Island, Connecticut, New Jersey 

 and Vermont, after a careful study of prices ruling 

 in the larger markets of the southern New England 

 and Middle States." 



Trade values of fertilizing ingredients in raw 

 materials and chemicals for 1904: 



Cents per Ib. 



Nitrogen in Nitrates 16 



Nitrogen in Ammonia Salts 



Organic Nitrogen in dry and fine ground fish, blood, 



and meat, and in mixed fertilizers 



Organic Nitrogen in fine ground bone and tankage . . 17 



Organic Nitrogen in coarse bone and tankage 12) 



Phosphoric Acid soluble in water 4j 



Phosphoric Acid soluble in ammonium citrate 4 



Phosphoric Acid in fine ground bone and tankage ... 4 



Phosphoric Acid in coarse bone and tankage 3 



Phosphoric Acid (insoluble in water and in ammonium 



citrate) in mixed fertilizer 2 



Potash as high-grade sulphate and in mixtures free 



from muriate (chloride) 



Potash as muriate 



For example, in calculating the commercial value 

 of the plant food in a fertilizer we will take the 

 formula mentioned on page 205, namely : 



Ammonia 2 to 3 per cent. 



Available Phosphoric Acid 8 to 10 " 



Total Phosphoric Acid II to 14 " 



Total Bone Phosphates 23 to 25 " 



Actual Potash 10 to 12 " 



Sulphate of Potash 18 to 2O " 



