1910.] PUBLIC DOCUMENT — No. 31. 57 



of nitrogen per pound in this material has been 17.1 cents in 

 line tankage and 13 cents in coarse tankage. 



])i!<solved Bone. — Three samples of dissolved hone have been 

 analyzed, only 1 of which was found deticient in plant food. 

 No commercial shortages were found. The average retail cash 

 price was $20.1)7, the average valuaticm <$20.Gf) and the percent- 

 age ditl'erence 28.90. 



Dry Ground Fi'SJi. — Twenty samples of dry ground fish 

 have been examined, of which 9 were found deficient in nitro- 

 gen and only 1 in phosphoric acid. Six brands showed a com- 

 mercial shortage ranging from a few cents to $1.89 per ton. 

 The average retail cash price was $38.90, the average valua- 

 tion $30.13 and the percentage difference 7.83. Nitrogen from 

 dry iish has cost, on the average, 23.88 cents per pound. 



Wood Ashes. — Thirteen samples ' of ashes have been ana- 

 lyzed, of which 3 were found deficient in phos])horic acid and 

 in potash. Six of these samples showed, a commercial short- 

 age ranging from 32 cents to $1.10 per ton. 



(1) Nitrogen Compounds. 



Sulfate of Ammonia. — Three samples have been analyzed 

 and found well up to the guarantee. The average cost of nitro- 

 gen per pound in this form has been 17.53 cents. 



Nitrate of Soda. — Thirteen samples have been analyzed, 

 only 2 being found deficient in nitrogen. The average cost of 

 nitrogen per pound in form of nitrate of soda has been 17.11 

 cents. 



Dried Blood. — Two samples of this material were examined 

 and found deficient in nitrogen ; each contained sufficient phos- 

 ])horic acid, however, so that there was no commercial shortage. 

 The average cost of nitrogen from blood has been 25.57 cents 

 per pound. 



Castor Pomace. — Four samples of castor pomace have been 

 analyzed, 1 sample only being found deficient in nitrogen, and 

 this equivalent to $2.30 per ton. The average cost of nitrogen 

 in this form has been 23.07 cents per pound. 



Linseed Meal. — Three samples of flax meal have been tested 

 and the nitrogen guarantee has been maintained in each in- 



