On the Combinations of [July, 



Article II. 



Farther Observations and Experiments on the Combinations of 

 Oxymuriatic Acid with Lime. By John Dalton. 



In my essay on the oxymuriate of lime (inserted in Vol. I. 

 No. I. of ihe Annals,) I gave my opinion that the muriate of 

 lime found in the oxvmuriate of commerce was accidental, and 

 not essential to the salt. I have lately been favoured with a 

 specimen of oxvmuriate of lime, immediately after its forma- 

 tion, by Dr. Henry. Oxymuriatic acid gas was passed through 

 a vessel containing a portion of water into another vessel con- 

 taining hydrate of lime, in the proportion of three parts lime to 

 one of water nearly: this was continued till the hydrate was 

 saturated. On the oxvmuriate thus prepared I made a few 

 i u-riments, which afforded me additional and satisfactory infor- 

 mation on the subject ; particularly as they confirm the opinion 

 that muriate of lime is not essential to the constitution of the 

 oxy muriate. 



E cper 1. — To 100 grains of the salt were added 1000 grains 

 of water; after due agitation and filtration, a liquid was ob- 

 tained of the sp. gr. 1*041 • a residuum of 21 grains, dried in 

 100, was also obtained; this, treated with test nitric acid, indi- 

 cates 16" grains of lime. One-fifth of the former liquid (1'041) 

 was treated with test carbonate of soda, and boiled • it threw 

 down o griins of carbonate of lime, equal to 4*5 of lime. Hence 

 th-i whole solution contained 22 grains of lime, of which 2 grains 

 muse have existed iu the solution, as in lime-water, and have been 

 borrowed of the precipitated lime. It appears, then, that 20 

 glairs of lime were held in solution by acid, and 18 precipitated, 

 of wl ich 2 were again taken up by the water of the solution. 

 Th^ total lime, then, in 100 grains of the dry oxymuriate was 

 38 .rains. This was confirmed by treating 20 grains of the dry 

 sa. with sulphuric acid, by which 181 grains of sulphate of lime 

 were obtained, which correspond to 38i grains percent, of lime. 



Thus, then, it appears, that the above specimen gives nearly 

 the same total of lime as that analysed in my former paper ; but 

 it contains more soluble matter, as is shown by the greater sp. gr. 

 of Ihe s , ut ion. 



Exper. 2. — It was found that 100 measures of the solution, 

 rOil, required 56 of test green sulphate of iron (1*149) to 

 annihilate the oxymuriatic acid. The calculation from this being 

 made as in my former, gives 23 grains of oxymuriatic acid in 

 luO of the dry salt. This acid would be in combination with 

 10 grains of lime ; but from the preceding experiment it seem? 



