<}4 ACTION OF POTASSIUM ON SALTS AND OXIDES. 



copper, Yellow and brown oxides of copper. Vivid inflammation. 



arsenic, White oxide of arsenic. Inflammation. 



cobalt, Black oxide of cobalt. Like the preceding. 



antimony, Volatile oxide of antimony. Inflammation, but less vivid 



than with the oxides of copper. 



Oxide of antimony at a maximum. Very vivid inflam- 

 mation. 

 tin, Oxide of tin at a maximum. Very vivid inflammation. 



Putty of tin. Inflammation, but less vivid than the pre- 

 ceding, 

 iron, Red oxide of iron. Very slight inflammation. 



Black oxide. No inflammation, but reduction of the 



manganese, 



bismuth, 

 zinc, 

 nickel, 

 and chrome. 



Fyrophorus. 



Action of po- 

 tassium on 

 earths. 



Siliceous flu- 

 oric gas. 



Decomposes 

 all substances 

 containing 

 oxigen, 



and indicates 

 its condensa- 

 tion. 



Oxides of manganese at a maximum. Very vivid inflam- 

 metion. 



Oxide at a minimum. No inflammation. 



Yellow oxide of bismuth. Vivid inflammation. 



White oxide of zinc. Reduction without inflammation. 



Gray oxide of nickel. Pretty vivid inflammation. 



Green oxide of chrome. No inflammation : production 

 of a blackish matter, which, when completely cooled, and 

 afterward exposed to the air, takes fire as an excellent pyro- 

 phorus, and becomes yellow. This matter is a combination 

 of potash and oxide of chrome, which in the air changes to 

 chvomate of potash. 



We likewise tried the action of the metal of potash on 

 earths, and particularly on zircon, silex, yttiia, and barytes, 

 and found, that it was evidently altered by all these; but 

 as we do not yet well know the cause of this alteration, we 

 shall not here enter into any particulars respecting it. We 

 fhall only say, it appears to us very probable, that the phe- 

 nomena observed in burning the metal of potash in silicious 

 fluoric gas are in no respect owing to the silex. 



Be this as it may, it follows from all the preceding facts, 

 that every substance, in which the presence of oxigen is 

 hitherto known, is decomposed by the metal of potash : that 

 almost all these decompositions take place with extrication 

 of light and heat: that move is disengaged in proportion as 

 the oxigen is less condensed : and. that consequently they 



afford 



