]?I<;RTILrzl5R INSPECTION. 53 



material of good quality) of an amount of nitrogen, phosphoric 

 acid and potash equal to that contained in one ton of the fer- 

 tilizer. Plaster, lime, stable manure and nearly all of the less 

 expensive fertilizers have variable prices, which bear no close 

 relation to their chemical composition, but guanos, superphos- 

 phates, and similar articles, for which $20 to $45 per ton are 

 paid, depend for their trade value exclusively on the sub- 

 stances, nitrogen, phosphoric acid and potash, which are com- 

 paratively costly and steady in price. The trade-value per 

 pound of these ingredients is reckoned from the current market 

 prices of the standard articles which furnish them to commerce. 

 The consumer, in estimating the reasonable price to pay for 

 high-grade fertilizers, should add to the trade-value of the 

 above-named ingredients a suitable margin for the expenses of 

 manufacture, etc., and for the convenience or other advantage 

 incidental to their use. 



trade; vaIvUe;s 01!" i^e^rtilizing ingre;die;nts. 



Cents 

 per ponnd 



Nitrogen in nitrates 17 



in ammonia salts 17^ 



Organic nitrogen in dry and fine ground fish, meat and 



blood,, and in mixed fertilizers. . 18^ 



in fine bone and tankage 18 



in coarse bone and tankage 13 



Phosphoric acid, water-soluble 45^ 



citrate-soluble 4 



of fine ground bone and tankage. ... 4 



of coarse bone and tankage 3 



of cotten seed meal, castor pomace, 



and ashes 4 



of mixed fertilizers, if insoluble in 



ammonium citrate 2 



Potash as high grade sulphate and in forms free from 



muriate (or chlorides) _. 5 



as muriate 4^ 



as carbonate 8 



A rule for calculating the commercial valuation of mixed fer- 

 tilizers is given on page 64. 



The results of the analyses of the manufacturers' samples of 

 fertilizers are given on the pages which follow. 



