PURCHASING PLANT-FOOD 



ignored by the purchaser who wants available 

 plant-food. 



The seventh gives the sum of the available and 

 insoluble, and should be ignored. 



The ninth is a restatement of the eighth line. 



There then remains the following guaranty : 



PHB CENT 



Nitrogen 0.82 



Available phosphoric acid 8.00 



Potash 1.00 



This is a low-grade fertilizer whose cheap char- 

 acter becomes apparent when the unnecessary 

 statements and restatements are erased. A ton 

 of it contains only 16 pounds of nitrogen, 160 

 pounds of phosphoric acid, and 20 pounds of 

 potash. 



Valuation of Fertilizers. The manufacturer 

 of a mixed fertilizer must make use of the unmixed 

 materials he finds upon the market. The prices 

 of the various plant constituents in the different 

 unmixed materials can be determined by averag- 

 ing quotations in leading markets for a given length 

 of time. The fair retail price is obtained by adding 

 about 20 per cent to the wholesale cash price. 

 The retail cash price per pound of the plant con- 

 stituents in leading markets is thus determined 

 o [193] 



