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not yet sufficienthj known. 161 



fhosphoric acid, diluted the mixture with distilled water, 

 and exposed it to distillation over a lamp. 



The fluid which passed over had not the smallest taste of 

 Acid, and produced no action on lacmus paper. As soon 

 as crystals began to be formed, the distillation was ended. 

 There were separated 45 grains of a salt which possessed 

 all the properties of muriate of barytes. 



By repeated distillation of the remaining acid fluid, which 

 had a verj- perceptible taste of phosphoric acid, I again ob- 

 tained by degrees the two gros of muriate of barytes, and as 

 little altered as the phosphoric acid w hich I had employed 

 for this experiment. 



My conjecture was still further confirmed by the follow- 

 ing experiments : 



1st. The solution of an ounce of muriate of barytes was 

 4iiixed with half an ounce of concentrated phosphoric acid, 

 by sufficiently diluting it with distilled water. 



' 2d. I evaporated the mixture in a glass capsule till it ap- 

 jicared dry on cooling. At the end of the operation a great 

 quantity of pungent muriatic vapours were disengaged. 



3d. The saline mass, which had a very acid taste, was 

 Kvashed with alcohol till the fluid no longer turned lacmus 

 )apcr red,, and until the salt was entirely freed from the ad- 

 lering acid. 



4th. The washed salt, when dissolved in distilled water, 

 gave a precipitate^ which when washed and dried weighed 

 'iO grains. 



5th. To ascertain the nature of this precipitate, which 

 <}iad no saline taste, and which made a noise under the teeth 

 like an earth, I boiled it with 30 grains of the carbonate of 

 ,<oda, and then edulcorated the liquor. 



6th. It dissolved completely in muriatic acid with very 

 flltllc efltTVcsccncc, and when mixed with sulphuric acid 

 ^gavc an abundant precipitate. 



7lh. The spirit of wine (3) which had taken up the salt 

 .ndhciing to the acid was distilled in a retort till the resi- 

 duum liad acquired the consistence of a syrup. 



Stli. Tlic result of the distillation, when a solution of 

 silver was dropped into it, showed traces of a little free 

 ^eid. 



f)th. The acid in the retort, which had a very perceptible 

 laste of phosphoric acid, was no longer impure by muriatic 

 iicid. Jt rendered lime water exceedingly turbid, and in 

 weight aniountod to three gros and thirty grains. 



]()ih. Tin saline solution (l) gave, after crystallization, 

 Voj.. X\ 11. >wo. tiC. L .seven 



A 



