ON FLUOR 15 



mass, which only was in weight the sixth part of the fixed 

 alkali dissolved; did not change the colour of syrup of 

 violets, but precipitated lime-water. The liquid above this 

 precipitate was a solution of pure alkali in water. The 

 same salt likewise precipitated the solutions both of 

 muriated lime and vitriolated magnesia. The precipitate 

 obtained from the lime-water and solution of muriated lime 

 was regenerated fluor. 



The gelatinous solution of fixed alkali in fluor acid was 

 well edulcorated, dried, and exposed to the fire in a close- 

 covered crucible. It melted without any ebullition. I then 

 took it out and powdered it. The taste was caustic. 

 Exposed in a cellar, it deliquesced, and showed itself in 

 every respect to resemble the liquor silicum. 



SECTION XXVIII. 



With mineral alkali, fluor acid yielded exactly the same 

 products as with the vegetable. 



SECTION XXIX. 



Volatile alkali dissolved in fluor acid likewise formed 

 a jelly, which, when it was separated from the liquid, and 

 well edulcorated, I found to be real siliceous earth. The 

 supernatant liquid had a taste resembling that of the 

 vitriolated volatile alkali, and yielded crystals, though indeed 

 very small, with which I tried the following experiments : 



(a) By sublimation, I at first obtained a little volatile 

 alkali, and afterwards sal ammoniac, of a taste rather acid. 



(5) Upon distillation, with a mixture of powdered chalk 

 and water, all the volatile alkali came over immediately. 



