in different chemical Processes on Pluor Spar. g(J^ 



/ interior contained a white crystalline mass, but there was no 



• appearance of fluid.* A poHshed brass tube, cooled by means 

 of ice, was held over the aperture of the platina tube, and it 

 was gently heated till the salt began to sublime, but no mois- 

 ture was found condensed in the cold tube of brass. 



This experiment is unfavourable to the idea, that the liquid 

 fluoric acid contains water ; and the following result is likewise 

 unfavourable to the idea that it consists of an inflammable 

 basis united to oxygen. Solid and perfectly dry fluate of am- 

 monia was introduced into a tray of platina, with about an 

 equal quantity of potassium, and the tray was heated in a small 

 tube of glass connected with a mercurial apparatus. A violent 

 action took place, gas was disengaged with great violence, 

 which remained for some time clouded ; the application of heat 

 was continued till the tube was red : it was then suffered to 

 cool, and the results examined. Much white matter, which 

 proved to be fluate of potassa, had been carried by the violence 

 of the action out of the tray of platina into the glass tube ; 

 and a little potassium had subhmed in the tube. The tray 

 contained a considerable portion of potassium, and a saline 

 matter, which had all the characters of fluate of potassa. The 

 gas disengaged, consisted of ammonia and hydrogen, to each 

 other in volume nearly as two to one ; but the experiment 

 cannot be considered as decisive on this point, as no particular 

 precautions had been taken to dry the mercury. 



• It is necessary that pure liquid fluoric acid, i. e. that which has the lowest $p«. 

 cific gravity, be used for this experiment. The first time that I made it, I obtained 

 moisture, owing to my having formed the hydro-fluoric acid by means of sulphuric 

 acid that had not been previously boiled, and which must have contained more than 

 ORC proportion of water. 



