218 AN ANALYSIS 



nate of soda. It was also to be presumed, that there would be 

 mixed with it any sulphate or carbonate of lime deposited du- 

 ring the evaporation. It was therefore re-dissolved in water. 

 There remained undissolved a residue, which, when thorough- 

 ly dried, weighed 22.6 grains. The salt was again procured 

 by evaporation, but it was still not perfectly pure. Its dilute 

 solution gave a milkiness with carbonate of soda ; and oxalate 

 of ammonia and muriate of barytes rendered it turbid, indica- 

 ting the presence either of a little muriate of lime with sul- 

 phate of soda, or magnesia, or of sulphate of lime with a por- 

 tion of sulphate or muriate of magnesia. The whole was re- 

 dissolved in distilled water, a powder similar in appearance to 

 the insoluble residue of the former solution, remained undis- 

 solved, which, when thoroughly dried, weighed 10.3 grains. 

 To the clear solution a portion of alcohol was added, not suffi- 

 cient to cause any precipitation of muriate of soda ; it produ- 

 ced a slight turbid appearance, and after some hours a powder 

 had subsided, which, after being washed with water, was 

 tasteless : it weighed 1.5 grains. The muriate of soda, obtain- 

 ed by evaporation, weighed, when dried, 718 grains. Being 

 still not entirely pure, it was reserved for another operation. 



E. The insoluble residues collected in the preceding opera- 

 tions being put together, were submitted to the action of alco- 

 hol, acidulated with muriatic acid, to remove any carbonate of 

 lime, or of magnesia. Effervescence was excited ; the liquor 

 being poured off, and the insoluble residue of sulphate of lime 

 being washed with a little water, weighed, after exposure to a 

 heat nearly equal to ignition, 26.3 grains. The alcoholic so- 

 lution, with the addition of the small portion of water with 

 which the sulphate of lime had been washed, afforded, by eva- 

 poration, a matter which entered readily into fusion, and 

 which, treated with sulphuric acid, gave 5.6 of sulphate, equi- 

 valent 



