THE USE OF MANURES. 



59 



phates. An analysis of South Carolina phosphate 

 shows it to contain 



Per cent. 



Moisture 7.79 



Organic matter and water of combination 4.60 



Silica 10.35 



Calcium carbonate 8.20 



Tricalcium phosphate 61.89 



Earthy and alkaline salts 7.17 



Total 100.00 



133. Hundreds of tons of cattle and buffalo bones 

 are brought from the Western Plains, and are either 

 used in the form of ground bones, or first converted 

 into superphosphate. The following mean of many 

 analyses of superphosphates, taken from " Phosphates 

 of Commerce," by Jones, will show their general 

 composition : 



Per cent. 



Moisture I4-5O 



Organic and volatile matter 12.91 



Monocalcium phosphate, or superphosphate *. . 17.30 



Tricalcium, or bone phosphate 4.16 



Calcium sulphate 47-78 



Alkaline salts 0.15 



Sand 3.20 



Total loo.oo 



* Equal to 27.08 per cent, of bone phosphate rendered sol- 

 able. " Monocalcium phosphate," in the above statement, is 

 sometimes called " biphosphate of lime." It is, according to 

 the modern chemical nomenclature, tetrahydrogen calcium di 

 phosphate. 



