48 CHEMICAL FERTILIZERS; AND LIME 



cts. per Ib. 



Nitrogen in ammonia salts 16 



Nitrogen in nitrates 16 



Organic nitrogen in dry and fine-ground fish, meat and blood and 



mixed fertilizers 20 



Organic nitrogen in fine-ground bone and tankage 20 



Organic nitrogen in coarse bone and tankage 15 



Phosphoric acid, water-soluble 4^ 



Phosphoric acid citrate, soluble (reverted) 4 



Phosphoric acid in fine-ground fish, bone and tankage .... 4 



Phosphoric acid in cottonseed meal, castor-pomace and ashes . 33^ 



Phosphoric acid in coarse fish, bone and tankage 3^ 



Phosphoric acid in mixed fertilizers, insoluble in ammonium citrate 



or water 2 



Potash as high-grade sulfate, in forms free from muriates (chlo- 

 rides), in ashes, etc 5 



Potash in muriate 4^ 



Valuation and cost of fertilizers. 



The total cost (to the farmer) of a ton of commercial fertilizer may 

 be regarded as consisting of the following elements: (1) Retail cash 

 cost, in the market, of unmixed trade materials ; (2) cost of mixing ; 

 (3) cost of transportation; (4) storage, commissions to agents and 

 dealers, selling on long credit, bad debts, etc. While the total cost of a 

 fertilizer is made up of several different elements, a commercial valua- 

 tion includes only the first of the elements entering into the total cost, 

 that is, the retail cash cost in the market of unmixed raw materials. 



Valuation, and agricultural value. 



The agricultural value of a fertilizer depends upon its crop-producing 

 power. A commercial valuation does not necessarily have any relation 

 to crop-producing value on a given farm. For a particular soil and 

 crop, a fertilizer of comparatively low commercial valuation may have 

 a higher agricultural value; while, for another crop on the same soil, 

 or the same crop on another soil, the reverse might be true. 



Rule for calculating approximate commercial valuation of mixed ferti- 

 lizers on basis of trade-values for 1910. 



Multiply the percentage of nitrogen by 4.0. 

 Multiply the percentage of available phosphoric acid by 0.8. 

 Multiply the percentage of insoluble phosphoric acid (total minus 

 available) by 0.4. 



Multiply the percentage of potash by 1.0. 



