EXPERIMENT STATION. 705 



agricultural chemists charged with the examination of com- 

 mercial fertilizers, cannot otherwise but benefit, ultimately, 

 both farmers and manufacturers. 



The market reports of centres of trade in New England, 

 New York and New Jersey, aside from consultations with 

 leading manufacturers of fertilizers, furnish the necessary 

 information regarding the current trade value of fertilizing 

 ingredients. The subsequent statement of cash values in 

 the retail trade is obtained by taking the average of the 

 wholesale quotations in New York and Boston, during the 

 six months preceding March 1, 1887, and increasing them 

 by twenty per cent., to cover expense for sales, credits, etc. 



These trade values, except those for phosphoric acid, 

 soluble in ammonium-citrate, were agreed upon by the Ex- 

 periment Stations of Massachusetts, Connecticut and New 

 Jersey, for use in their several States for the present season. 



Teade Values of Fertilizing Ingredients in Raw 

 Materials and Chemicals. 



1887. 

 Cents per round. 



Nitrogen in nitrates, 16 



Nitrogen in ammoniates, 17^ 



Organic niti'ogen in dried and fine-ground fish, .... 17^ 

 Organic nitrogen in Peruvian guano, blood, meat, azotin, ammo- 

 nite, and castor jjomace, 17J 



Organic niti'ogen in fine-ground bone and tankage, ... 10 



Organic nitrogen in fine medium bone and tanlvage, ... 14 



Organic nitrogen in medium bone and tankage, .... 12 



Organic nitrogen in coarse medium bone and tankage, . . 10 



Organic matter in coarse bone, horn shavings, hair and fish scrajDs, 8 



Phosphoi'ic acid, soluble in water, 8 



Phosphoric acid, soluble in ammonia citrate,* .... 7^ 

 Phosphoric acid, insoluble, in dry, fine-groimd fish, in fish bone 



and tankage, 7 



Phosphoric acid, insoluble, in fine, medium bone and tankage, . 6 



Phosphoric acid in medium bone and tankage, .... 5 



Phosphoric acid in coarse medium bone and tankage, ... 4 



Phosphoric acid in coarse bone and tankage, .... 3 



Phosphoi-ic acid in fine-ground rock phosphate, .... 2 



Potash as sulphate, in compounds free from chlorine, ... 5^ 



Potash as kainite, 4J 



Potash as muriate, 4J 



♦Dissolved from two grams of phosphate, ungroimd, by 100 c.c. neutral solution 

 of ammonium citrate, sp gr. 1.09, in 30 minutes, at 65 deg. C, with agitation once in 

 five minutes, commonly called "reverted " or " backgone " phosphoric acid. 



