1S6 On some new anahj ileal Researches 



-that it was comljincd at the surFacc with phosphorus, and 

 gave phosphureited hydrogen by itsopcraiion ii|)on water. 



I endeav'o'.nedj by repcatcdlv distilling the fluid i'rom po- 

 tassium in a close vessel, to iVcc it from phosphorus, and 

 in this way I succeeded in depriving it ot a considerable 

 quantity of this substance. 



I inlroduccd ten or twelve drops of the liquid, which had 

 been thus treated, into a f^mall plate glass fetort, conlain- 

 ing six grains of potassium ; the retort was exhausted after 

 having been twice lilled with liydrogen, the li()uid was made 

 to boil, and the retort kept warm till the whole had dis- 

 appeared as clastic vapour. The potassium was then heated 

 by the point of a spirit.lainp ; it liad scarcely melted, when 

 it burst into a most brilliant flame, as splendid as tliat of 

 phosphorus in oxygen gas, and the reiort was destroyed by 

 the rapidily of combusTion. 



In other trials made upon smaller quantities after various 

 failures, I was at last able to obtain the results ; there was 

 no proof of the evolution of any permanent clastic fluid 

 during the operation. A solid mass remained of a greenish 

 colour at the surface, but- dark gray in the interior. It was 

 extremely inflammable, and often burnt spontaneously 

 when exposed to air ; when thrown upon water, it produced 

 a violent explosion, wi.th a smell like that of phosphuretted 

 hydrogen. In the residuum of its combustion there was 

 found muriate of potash, and phosphate of potash. 



I endeavoured to perform this experiment in an iron tube, 

 hoping that if the muriatic acid was decomposed in the 

 process, its inflammable element, potassium and phospho- 

 rus, might be separated from each other by a high degree 

 of heat; but in the first part of the operation the action 

 was so intense, as to produce a destruction of the apparatus, 

 and the stop-cock was separated from the uibe witk a loud 

 detonation. 



I heated potassium in the vapour of the compound of 

 xnuriatic and phosj)horic acid ; but in this case the in- 

 flammation was still more intense, and in all the experi- 

 ments that I have hitherto tried, the gla^s vessels have been 

 either fused or broken ; the solid residuum has however ap- 

 peared to be of the same kind as that I have just described. 



The results of the operation of the sulphuretted com- 

 pounds containing muriatic acid free from water upon po- 

 tassium, are still more extraordinary than those of the phos- 

 phuretted compounds. 



When a piece of potassium is introduced into the sub- 

 SlaiKC that distils over during the action of healed sulphur 



upon 



