ON FLUOR 



SECTION IX. 



The remaining residuum of the former distillation, after 

 being perfectly edulcorated by means of distilled water, was 

 boiled repeatedly with rain-water, until seven cans of water 

 were used, whereby everything soluble in water was dissolved, 

 since nothing was precipitated from the last water employed, 

 by adding alkali of tartar. The mass now remaining was 

 one-fourth of the whole employed. It was reduced to fine 

 powder, and calcined with acid of vitriol to dryness. In the 

 beginning of this operation, a quantity of corrosive vapours 

 were separated from the mass, which at the same time 

 swelled considerably. After the vessel was cooled, I reduced 

 the mass to a very fine powder, boiled it in pure water, and 

 found it entirely dissolved. On part of this solution I 

 poured some caustic volatile alkali, which produced no 

 precipitation ; but, by means of alkali of tartar, true cal- 

 careous earth was precipitated. A can of the liquor, from 

 which the precipitation was obtained, yielded upon evapora- 

 tion vitriolated vegetable alkali. The alkali at the same 

 time decomposed an earthy salt (selenite), which was 

 dissolved in the water. The remaining fourth part, not 

 soluble in water, was powder of fiuor undecomposed. 



SECTION X. 



Fluor, therefore, consists principally of calcareous earth, 

 saturated with a peculiar acid ; the nature of which we 

 shall investigate hereafter. Pure clay, or, as it is gener- 

 ally called, earth of alum, and iron seem to be acci- 

 dental ingredients. The following experiments will prove 

 this synthetically. 



