NEUTRAL ALKALINE PHOSPHATES. 



ACTION OF THE NEUTKAL PHOSPHATES OF THE ALKALIES 

 UPON CAEBONATE OF LIME. 



It is a fact that, notwithstanding the advanced state of the 

 science of chemistry, we are ignorant of some of the laws that 

 govern the relative affinities of acids for bases, and the action 

 of neutral salts upon each other. It is true such and such 

 acids are ranked according to what is termed their strength, 

 and such bases are said to be more powerful than others; still 

 from time to time facts are developing themselves that contra- 

 dict these established rules. The decomposition of the sulphate 

 of lead by certain neutral alkaline salts (Am. Jour., xlvii, 81) 

 I thought could be explained upon a known law, that when 

 there existed two acids and two bases in solution (the sulphate 

 of lead being dissolved by the salts used) the stronger acid 

 sought the stronger base, and the feebler acid had to combine 

 with the feebler base, notwithstanding being originally in com- 

 bination with an alkali. But how are we to explain the fact 

 about to be mentioned, which, so far as my information goes, 

 has not been previously observed? It is that the feeblest solu- 

 tion of the neutral phosphate of soda or potash will decompose 

 the carbonate of lime in the cold, giving rise to carbonate of soda 

 and phosphate of lime. 



This fact was first observed while analyzing the ashes of a 

 plant, which was fused with carbonate of soda, for the purpose 

 of estimating the phosphoric acid. The fused mass was thrown 

 into about four ounces of water, and digested at about 180° 

 Fah. for a couple of hours. The insoluble portion was sepa- 

 rated and treated with an acid, when to my astonishment it 

 dissolved with but a very slight effervescence; in fact, with the 

 escape of only a bubble or two of gas, the carbonate of lime 



