332 BOARD OF AGRICULTURE. 



application, is a universally indorsed practice. The good 

 economy of applying these phosphates in a finely divided state 

 to the compost heap, has been illustrated again quite recently 

 by Prof. H. C. White, of Georgia. 



The experiments were made with a finely ground South 

 Carolina phosphate. The compost heap was prepared of 40 

 parts of earths, 34 parts of fine ground phosphate, and 31 

 parts of cotton-seed cake, and the mixture kept moist with 

 water. 



The compound was made in June, and tested in February. 

 A careful estimation proved that one-third of the phosphoric 

 acid had been rendered soluble in soil-water ; the commercial 

 value of the phosphoric acid had been increased not less than 

 46.4 per cent. It is quite safe to assume that any of the 

 above stated phosphates treated in a similar way with fresh 

 horse-manure or turf, and kept moist with urinary excretions, 

 would have given even still higher pecuniary results. 



BONE-ASH FROM SOUTH AMERICA. 



Phosphoric acid, 35.89 



Lime 44.89 



Sand, etc., 4.50 



Moisture, 7.00 



This material was guaranteed to contain 75 per cent, of 

 bone phosphate ; it contained 78.2 per cent, of that com- 

 pound. The price was stated to be $28 gold, which is rather 

 higher than we are usually asked to pay for phosphoric acid in 

 other equally valuable phosphates. The bone-ash of South 

 America, although produced in unusually large quantities, is 

 only of incidental occurrence in our markets ; for the main 

 bulk, it seems, is carried to Europe. It comes as a ballast 

 to some of our seaport towns, and furnishes an excellent mate- 

 rial for the manufacture of superphosphate. The above 

 described article consisted largely of coarse fi'agments of cal- 

 cined bones, and of a fine grayish white powder ; the latter 

 contains usually besides bone-ash some wood-ash and some 

 sand in varying proportions. 



Valuation 2)er ton of South American Bo7ie-Ash. 

 717.8 tbs. of phosphoric acid, at 4 cts. per ft., . . $28 61, currency. 



