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115. FERTILIZERS. 



TARIFF OF PRICES OF COMMERCIAL FERTILIZERS. 



e. In 1857, A. Stockhardt, of Tharand, published a 

 tariff of prices of commercial fertilizers, with the aid of 

 whicli, in a very simple manner, the cost of the mannre 

 could bo compared with its real value ; in this tariff, the 

 estimation of the money value of each of the three im- 

 portant constituents of these fertilizers in general, was 

 based upon the price that would have to be paid for it in 

 other and also commercial forms, containing a known and 

 often guaranteed proportion of tlie substance. The per 

 cent composition of a fertilizer being known, the pur- 

 chaser could then tell, on consulting the tariff, whether he 

 was required to pay any more for the number of pounds of 

 nitrogen or pliosphoric acid in 100 pounds of the article 

 lie was buying, than he would have to pay for the same 

 number of pounds of nitrogen in the form of sulphate of 

 ammonia, from the gas-works, for example, or of phos- 

 phoric acid in tlie bone-black of the sugar refiners. 



A greatly improved form of this tariff, which was put 

 out by Stockhardt in 1866 ( Chemische Ackersmann, 1866, 



