Dr. J. L. Smith on Neutral Alkaline Phosphates. 97 



Art. X. — (1.) Action of Solutions of the Neutral Phosphates of 

 the Alkalies upon the Carbonate of Lime, and some other in- 

 soluble Carbonates ; (2.) Source of Fluorine in Fossil Bones ; 

 (3.) Composition of the Marl from Ashley River, S. C, with 

 an extract from a letter written by Prof Bailey of West Point; 

 (4.) Existence of the Oxide of Cobalt in South Carolina ; by 

 J. Lawrence Smith, M. D. 



I. Action of Solutions of the Neutral Phosphates of the Alkalies 

 upon the Carbonate of Lime, ^"c. 



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

 ence of chemistry, we are ignorant of some of the laws that gov- 

 ern the relative affinities of acids for bases, and the action of neu- 

 tral 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 contradict these established 

 rules. The decomposition of the sulphate of lead by certain neu- 

 tral alkaline salts, (Am. Journ. xlvii, 81,) I thought could be ex- 

 plained 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, notwith- 

 standing being originally in combination 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 solution 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° Fahr. for 

 a couple of hours ; the insoluble portion was separated, and treat- 

 ed with an acid, when to my astonishment it dissolved with but 

 a very slight effervescence, in fact with the escape of only a bub- 

 ble or two of gas, the carbonate of lime expected not being pres- 

 ent. It was known that this circumstance could not arise from a 

 want of decomposition of the original matter, as it was kept fused 



Vol. XLViii, No. 1.— Oct.-Dec. 1844. 13 



