1912.] PUBLIC DOCUMENT — No. 31. 53 



centage difference 5.10. Two of the brands analyzed showed a 

 commercial shortage of 50 cents or over a ton. 



Eighteen samples of tankage have been analyzed. Three 

 were found deficient in nitrogen and 5 in phosphoric acid. The 

 average retail cash price per ton was $34.14, the average valua- 

 tion per ton $32.69, and the percentage difference 4.43. Nitro- 

 gen in fine tankage has cost on the average 20.89 cents ; nitrogen 

 in coarse tankage has cost 15.G5 cents per pound. Three sam- 

 ples have shown a commercial shortage of over 50 cents per ton. 



Twenty-two samples of dry ground fish have been examined. 

 Three were found deficient in nitrogen and 2 in phosphoric 

 acid. The average retail cash price per ton was $41.90, the 

 average valuation $42.71, and the percentage difference in ex- 

 cess 1.93. Nitrogen from dry ground fish has cost on the aver- 

 age 22.56 cents per pound. None of the brands showed a 

 commercial shortage of over 50 cents per ton. 



(1) Nitrogen Compounds. — Three samples of sulfate of 

 ammonia have been analyzed and found well up to the guaran- 

 tee. The average cost of a pound of nitrogen in this form has 

 been 16.78 cents. 



Twenty-three samples of nitrate of soda have been analyzed 

 and 3 were found deficient in nitrogen. The average cost of 

 nitrogen in this form has been 16.19 cents per pound. 



Four samples of dried blood have been examined which, with 

 one exception, showed overruns in nitrogen. The pound of ni- 

 trogen from blood has cost 23.29 cents. 



Four samples of castor pomace have been analyzed. The 

 average cost of nitrogen in this form has been 26.11 cents per 

 pound. 



Twenty-three samples of cottonseed meal have been exam- 

 ined, all of which were purchased as a nitrogen source for 

 tobacco. Nitrogen from this source has cost on the average 

 23.08 cents per pound. Six samples have shown a nitrogen 

 deficiency which has, in 3 cases, amounted to 50 cents or more 

 per ton. 



(2) Potash Compounds. — Twenty-one samples of high 

 grade sulfate of potash have been examined, and the potash 

 guarantee was maintained in all but one instance. The pound 



