October, 1923] fertilizer inspection, 1923 5 



ing 4 per cent, of nitrogen has four units of nitrogen or 80 

 pounds per ton. 



Prices of Plmit Foods. It is impossible to give ac- 

 curate figures for the cost of the different plant foods be- 

 cause the cost of mixing, bagging, freight and the manu- 

 facturers' and dealers' profits vary with the quantity pur- 

 chased, distance shipped and number of persons through 

 whose hands the material has passed. It is possible, how- 

 ever, to obtain figures which are sufficiently accurate for 

 use in comparing the relative values of fertilizers. 



The average cost of acid phosphate containing 16 per 

 cent, of phosphoric acid was $32.60 per ton. One ton con- 

 tained 0.16 times 2,000 pounds or 320 pounds of available 

 phosphoric acid. The cost per pound was $32.60 divided 

 by 320 or approximately 0.102 and one unit of available 

 phosphoric acid cost 20 times 0.102 or approximately $2.04. 



The average cost of muriate of potash containing 50.0 

 per cent, of water soluble potash was $50.00 per ton. One 

 ton contained 0.50 times 2,000 pounds or 1,000 pounds of 

 potash. The cost per pound was $50.00 divided by 1,000 

 or $0.05 and one unit of water soluble potash cost 20 times 

 0.05 or $1.00. 



The average cost of nitrate of soda containing 15 

 per cent, nitrogen was $71.80 per ton. One ton contained 

 0.15 times 2,000 or 300 pounds of nitrogen; this made the 

 cost price per unit 20 times $0.24 or $4.80. The average 

 cost of tankage was $62.50 per ton and it contained an aver- 

 age of 5.50 per cent, of nitrogen and 4.63 per cent, available 

 phosphoric acid. The value of the 4.63 units of phosphoric 

 acid was 4.63 times $2.04 or $9.45, making the nitrogen 

 cost $62.50 minus $9.45 or $53.05. The cost per unit of 

 nitrogen was $53.05 divided by 5.50 or $9.65 and the cost 

 per pound of nitrogen $0,482. If we assume that our com- 

 plete fertilizers contain both forms of nitrogen, we can 

 approximate an average and use the values of $0.36 per 

 pound and $7.20 per unit for nitrogen of complete fertili- 

 zers. These figures will not give the price at which fertil- 



