290. . HOME-MADE SUPERPHOSPHATE. 



Sent on for examination, from Marblehead, Mass. 



Per Cent. 

 Moisture at 100° C, 26.03 



Total phosplioric acid, 12.78 



Soluble " " 10.87 



Reverted " " 0.59 



Insoluble " " 1.32 



Insoluble matter, 16.04 



Valuation, per ton of 2,000 lbs. : $21.04. 



The article was obtained, according to a communication received, 

 by treating one thousand pounds of fine-ground South Carolina rock 

 phosphate with six hundred pounds of sulphuric acid of 66° B., specific 

 gravity, diluted previously with an equal volume of water. As the 

 mixture thus produced remains, for some time, more moist than 

 desirable, it is recommended to use equal weights of acid and water. 



291. FINE 



Moisture at 100" C, 

 Total phosphoric acid, 

 Reverted " " 



Insoluble " " 



Nitrogen, 

 Insoluble matter. 



Valuation per 2,000 lbs. : $43.27 $44.96 



The valuation of ground bones varies, somewhat, on account of 

 differences in their mechanical condition. The majority of these arti- 

 cles are at present of a very advantageous form. 



292. L. B. Darling's Fine Ground Bones. Collected of J. H. 



Fairbanks, Fitchburg, Mass. 



Guaranteed composition : phosphoric acid, 22 to 25 per 

 cent. ; bone phosphate, 52 to 55 per cent. ; nitrogen, 3.5 to 

 4.5 per cent, (equivalent to ammonia, 4 to 5 per cent,). 



293. Belknap & Co.'s Pure Ground Bones. Collected of J. & J. 



A. Rice, Worcester, Mass. 



Guaranteed composition: bone phosphate, 56 to 80 per 

 cent. ; phosphoric acid, 24 to 38 per cent. ; nitrogen, 4.41 

 per cent, (equivalent to ammonia, 5.35 per cent). 



