56 



EXPERIMENT STATION. 



[Jan. 



The analyses were made in accordance with methods adopted 

 by the Association of Official Agricultural Chemists. The 

 analysis of a composite sample was made whenever possible, 

 and in instances where such an analysis has shown a brand to be 

 seriously deficient in one or more elements, a new portion was 

 drawn from each original sample collected and a separate analy- 

 sis made. This was done to determine whether the shortage 

 was confined to one sample or whether it was general in case 

 of that particular brand. 



Twelve samples of lava fertilizer, so called, were analyzed. 

 Although these materials have not been offered for sale in 

 Massachusetts, considerable literature concerning them has 

 been circulated, and it was thought best to have representative 

 samples examined and the results published. 



Thirty-two more analyses \vere made than during the pre- 

 vious year. 



Trade Values of Fertilizing Ingredienis. 

 The following table of trade values of fertilizer ingredients 

 was used. It was adopted by the experiment stations of l^ew 

 England, New Jersey and Isew York at a meeting held in 

 March, 1910. For purposes of comparison the 1009 schedule is 

 also given. 



Cents per Pound. 



Nitrogen: — 

 In ammonia salts, ........... 



In nitrates, ............ 



Organic nitiogen in dry and fine ground fish, meat, blood, and in high- 

 grade mixed fertilizers, ......... 



Organic nitrogen in fine ' bone and tankage, ..... 



Organic nitrogen in coarse ' bone and tankage, ..... 



Phosphoric acid: — 

 Soluble in water, . . . . . . . 



Soluble in neutral citrate of ammonia solution (reverted phosphoric 

 acid),^ ............ 



In fine ' bone and tankage, . . . . . • . 



In coarse ' bone and tankage, ........ 



In cottonseed meal, linseed meal, castor pomace and ashes, . 



Insoluble in neutral citrate of ammonia solution (in mixed fertilizers), 



Potash: — 

 As sulfate, free from chlorides, ........ 



As muriate (chlorides), .......... 



As carbonate, ............ 



> Fine and medium bone and tankage are separated by a sieve having circular openings one- 

 fiftieth of an inch in diameter. Valuations of these materials are based upon degree of fineness 

 as well as upon composition. 



* Dissolved by a neutral solution of ammonium citrate; specific gravity 1 09 in accordance 

 with method adopted by the Association of Official Agricultural Chemists. 



