142 - ELEMENTS OF AGRICULTURE 



136. Valuation of Fertilizers. — Commercial fertili- 

 zers are talued according to the amounts of nitrogen, 

 phosphoric acid and potash they contain, and, in order 

 to protect the consumer from dishonest manufacturers, 

 most States have employed chemists whose business it 

 is to examine all fertilizers sold in their State, to see 

 if they contain what the manufacturers claim for them. 

 Each package of fertilizer sold must have printed on 

 it the amounts of nitrogen, phosphoric acid, and potash 

 it contains, so that buyers may know what they are 

 getting. Each State chemist fixes a value per pound 

 for nitrogen, phosphoric acid and potash, and with 

 them anyone may calculate the value of any commer- 

 cial fertilizer. Suppose, for instance, that nitrogen 

 is valued at 15 cents a pound; then if a fertilizer con- 

 tains 2 per cent of nitrogen its supply is worth $6.00 

 per ton. If the fertilizer contains also 8 per cent of 

 available phosphoric acid which is valued at 4 cents 

 a pound, its supply of phosphate is worth $6.40 per 

 ton. If, besides nitrogen and phosphoric acid, the fer- 

 tilizer contains 1 per cent of potash valued at 5 cents 

 a pound, its potash is worth $1.00 per ton, making a ton 

 of the fertilizer worth $13.40. 



Nitrogen, 2% of 2,000 lbs. = 40 lbs. at 15tf per lb. = $ 6 00 

 Phosphoric acid, 8% of 2,000 lbs. = 160 lbs. at 4tf per 



lb.= 6 40 



Potash, 1% of 2,000 lbs. =20 lbs. at 5tf per lb. = 1 00 



$13 40 



The valuations placed on nitrogen, phosphoric acid 

 and potash by official chemists are based upon the 



