124 FERTILITY AND FERTILIZER HINTS 



How Obtained. — To give an idea of how these trade values are 

 obtained we may presume that the wholesale price of sulphate 

 of ammonia for the six months preceding March ist averaged 

 $56.80 per ton, or 14.2 cents a pound for the nitrogen. A cer- 

 tain amount, usually 20 per cent, is added to this wholesale price 

 to cover the cost of handling, insurance, etc., which would raise 

 the price to $68 i^er ton, which would be the retail or commercial 

 value of ammonium sulphate. The nitrogen then would be 

 represented as carrying a commercial or trade value of 17 cents 

 a pound. The trade values on all other fertilizer materials are 

 calculated in the same way as described for sulphate of ammonia. 



A Discussion of the Table of Trade Values. — A study of the 

 table is interesting. It shows that valuations are given for 

 nitrogen as nitrate, as ammonia and as organic nitrogen. The 

 trade values for organic nitrogen are also different depending 

 upon the source. Soluble phosphoric acid is valued higher than 

 reverted phosphoric acid and there is also a trade value for in- 

 soluble phosphoric acid. In some states there is no distinction 

 made between soluble and reverted phosphoric acid in trade 

 valuation and the insoluble phosphoric is often not considered at 

 all. The bone products in the foregoing table are valued on their 

 degree of fineness ; the finer bone-meals command higher market 

 prices than those that are coarse as is shown in the trade valua- 

 tions of nitrogen and phosphoric acid. The potash as sulphate 

 carries a higher trade value than potash as chloride, but this is 

 to be expected because sulphate of potash costs more to manu- 

 facture than muriate of potash. There are many fertilizer 

 materials not included in the above table. Those included in 

 the table are high class products commonly used in New England 

 and New Jersey. 



How to Calculate the Commercial Value of a Fertilizer. — Let us 

 suppose a chemist analyzes a mixed fertilizer and finds its com- 

 position to be as follows : 



