EXPERIMENT STATION. 513 



The above trade values are the figures at which, on ]\Iarch 1, 

 1886, the respective ingredients could be bought at retail for 

 cash per pound in our leading markets in the raw materials, 

 which are the regular source of supply. 



They also correspond to the average wholesale prices for the 

 six months ending March 1, plus 20 per cent in case of goods 

 for which we have wholesale quotations. The calculated values 

 obtained by the use of the above figures will lie found to agree 

 fairly with the reasonable retail prices in case of standard raw 

 materials, such as — 



Sulphate of Ammonia, Dry Ground Fish, 



Nitrate of Soda, Castor Pomace, 



Muriate of Potash, Cotton Seed, 



Sulphate of Potash, Bone, 



Dried Blood, Azotin, 

 Plain Superphosphates. 



Trade Values in Superphosphates, Special Manures and 

 Mixed Fertilizers of High Grade. 



The organic nitrogen in these classes of goods are here 

 valued at the highest figures laid down in the trade values 

 of fertilizing ingredients in raw materials, namely, 17 cents 

 per pound ; it being assumed that the organic nitrogen is de- 

 rived from the best sources, as bone, blood, animal matter, 

 or other equally good forms, and not from leather, shoddy, hair 

 or any low-priced inferior form of vegetable matter, unless the 

 contrary is ascertained. 



Insoluble phosphoric acid has been valued at 3 cents, it being 

 assumed, unless found otherwise, that it is from bone or a simi- 

 lar source, and not from rock phosphate. In this latter form 

 the insoluble phosphoric acid is worth but 2 cents per pound. 

 Potash is rated at 4^ cents per pound, if sufficient chlorine 

 is present in the fertilizer to combine with it to make 

 muriate. 



If there is more potash present than will coml)ine with the 

 chlorine, then this excess of potash will be counted as sulphate. 

 To introduce large quantities of chlorides, common salt, etc., 

 into fertilizers, claiming sulphate of potash as a constituent, is a 

 practice which, in our present state of information, will be con- 



