ACTION OF POTASSIUM ON AMMONIA. Qjf 



Is very soluble in hidrogen; but, under common circum- 

 stances, hidrogen does not seem to be absorbable by pot- 

 assium. 



When potassium is heated in hidrogen in a flint glas"s retort, or 

 even for a great length of time in a green glass retort, there is an *b- Hidrogan ab- 

 sorption of the gasj but this is independent of the presence of pot- sorbed by the 

 assium, and is owing to the action of the metallic oxides in the glass ox| des in the 



iL vj glass, 



upon the hidrogen. 



If a solid compound of hidrogen and potassium could be formed, we 

 might expect its existence in the experiment with the gun barrel, in 

 which potassium is exposed to hidrogen at almost every temperature} 

 but the metal formed in this process, when proper precautions are 

 taken to exclude carbonaceous matters, is uniform in its properties, and 

 generates, for equal quantities, equal proportions of hidrogen by the 

 action of Mater. ,, 



The general phenomena of this operation show indeed, that the so- 

 lution of potassium in hidrogen is intimately connected with the gene- 

 ral principle of the decomposition; and confirm my first idea of the ac- 

 tion of the two bodies. 



Hidrogen dissolves a large quantity of potassium by heat, but the * 

 greater portion is precipitated on cooling. The attractions which de- 

 termine the chemical change seem to be that of iron for exigen, of irort 

 for potassium, and of hidrogen for potassium ; and in experiments, in 

 which a very intehse heat is used for the production of potassium by 

 iron, I have often found, that the gas which comes over, though it has 

 passed through a tube cooled by ice, inflames spontaneously in the 

 atmosphere, and burns with a most brilliant light, which is purple at 

 the edges, and throws off a dense vapour containing potash. 



Sodium appears to be almost insoluble in hidrogen, and this seem*! Sodium neatlr 

 to be one reason why it cannot be obtained, except in very minute insoluble in 

 quantities, in the experiment with the gun barrel. hidrogen. 



Sodium, though scarcely capable of being dissolved in hidrogen 

 alone, seems to be soluble in the compound of hidrogen aud potassium. 

 liy exposing mixtures of potash aud soda to iguited iron I have ob- 

 tained some very curious alloys ; which, whether the potassium or the Curious alloys, 

 sodium was in excess, were fluid at common temperatures. The com- 

 pound containing an excess of potassium was even light than pot- 

 assium (probably from ita fluidity). AW these alloys were in the 

 highest degree inflammable. When a globule of the fluid alloy was 

 touched by a globule of mercury, they combined with a heat that 

 singed the paper upon which the experiment was made, and formed, 

 vhen cool, a solid so hird, as not to be cut by a knife. 



(To be continued in our next. J 

 Vol, XXIII.—Avgust, 1809- S On- 



