94 HATCH EXPERIMENT STATION. [Jan. 



was given a half cent higher valuation than in the previous 

 year. 



The above trade values are, as in years past, based on the 

 market cost, during the six months preceding March, 1901, 

 of standard raw materials which enter largely into the manu- 

 facture of commercial fertilizers found in our markets. The 

 following is a partial list of such materials : — 



Sulfate of ammonia. 

 Azotine. 



Cotton-seed meal. 

 Linseed meal. 

 Bone and tankage. 

 Nitrate of soda. 

 Dried blood. 

 Castor i^omace. 

 Dry ground fish. 

 Dry ground meat. 



Dissolved bones. 



Acid phosphate. 



Refuse bone-black. 



Ground phosphate rock. 



High-grade sulfate of potash. 



Sulfate of potash and magnesia. 



Muriate of potash. 



Kainit. 



Sylvinite. 



Crude saltpetre. 



In order to use the table of trade values in calculating 

 the approximate value of a fertilizer, calculate the value of 

 each of the tliree essential elements of plant food — nitro- 

 gen, phosphoric acid and potassium oxide (including the 

 different forms of each wherever different forms are recog- 

 nized in the table) — in one hundred pounds of the ferti- 

 lizer, and multiply each product by twenty, to raise it to a 

 ton basis. The sum of these values will give the total 

 value of the fertilizer per ton at the principal places of dis- 

 tribution. An example will suffice to show how this calcu- 

 lation is made : — 



Analysis of Fertilizer {^Per Cent., or Pounds in One Hundred 

 Pounds of Fertilizer) . 



Nitrogen, 4 



Soluble phosphoric acid, 8 



Reverted phosphoric acid, 4 



Insoluble phosphoric acid, 2 



Potassium oxide (as sulfate) , . . , . . .10 



