A. A. Ramsay 



291 



Total 



53-04 



53-06 



100-00 



21-15 



>1-18 



100-00 



24-02 



-f 29-02 



53-04 



Actually present 



It will be noted that 93-2 % of the total lime and 84-3 % of the total 

 phosphoric acid present have gone into solution in the first extraction. 

 The Hme extracted is 28-4 grams more than the amount necessary to 

 form CagPaOg with the P2O5 found, an amount which is nearly the same 

 as that contained in the calcium carbonate added. In the second 

 extraction the lime found is considerably more than that which would 

 be required to combine with the P2O5 found to form CagPgOg , indi- 

 cating that a considerable amount of lime has gone into solution as 

 calcium citrate. In the third extraction the amount of lime found is 

 just about the amount which would be necessary to produce dicalcic 

 phosphate (-22) with the P2O5 found. The same remark applies to the 

 amount of lime found in the fourth extraction, the lime and phosphoric 

 acid found are in the proportions in which they existin dicalcic phosphate. 



It will also be noted that here again the so-called "citrate soluble" 

 phosphoric acid has fallen from 91 % as in experiment {a) to 84-3 % of 

 the total phosphoric acid present. 



The extraction of mixtures of a higher calcium carbonate content 

 was not tested, as it was considered that in practice few phosphates 



