ON THE METALS OF THE ALKALIS. 2g^ 



tnoist, formeH at length an alkaline liquid, and the mercury 



beta tne fluid. The te«denry of this amalgam to coin bi ne & has & strong 



with other metals is surprising, it combines even with iron o^e^ me[ 1 



at the instant of contact, and extends on its surface; but 



after some time the metalloid returns to the state of potash, 



and the mercury j^epurates from the iron. 



Twenty-five grains of the metalloid of potash being heatr Potas«5ium 



cd red hot in a nurrow-moulhid vessel, 4he small globules ^^'*^^** ^^^ ^^^ 



' ; " Ui a narrow 



united into larger, which l^ad a bright metallic lustre, that mouthed Tes- 



wa« a mean between that of tin ami that of silver, and were ^^^> 



very iluid. On cooling they assumed the appearance of a 



hard amalgam of tin. In the open air they became covered and afterward 



at first with a gray coat, which became blue in a greater *'*'^^'^^^*^.*^* 



r^ J ' » action of air, 



heat, and the blue colour of which grew much deeper, 



when the gray pellicle was removed from the melted matter. 

 On heating it more strongly all the colour disappeared, and and of heat. 

 the uhole assufned a silver whiteness, with a metallic lustre, 

 which became gray on cooling. A little of the fused mat- 

 ter, being brought into contact with the air, took fire, and 

 gave out a white vapour, not alkaline, which deserves exa- 

 mination. On heating it to a cherr}' red, a liquid matter 

 was produced of a yellow brown colour, and destitute of 

 metallic lustre, which gradually became of a blue green, 

 and comported itself as a siliceous compound that attracted 

 moisture from the air. Potash therefore was formed with- 

 out previous inflammation, and the metalloid of potash had 

 attacked the glass, agreeably to the experiments of Mr. 

 Davy. 



Some time ago I treated alkaline matter, from which I potassium oIj- 

 had failed to obtain metalloid, with linseed oil, according ta'"e<J by 

 to Curaudau s process*. Havuig subjected it to a very vio- .^qq^ qji, 

 lent heat, I could obtain no fluid metalloid in the receiver; 

 but in the necl> of the retort 1 found a portion in clots, 

 mixed with carbonaceous matter, weighing about two 

 drachms. On heating it, and straining it through a rag 

 under heated petroleum, 1 obtained half a drachm of liquid 

 metalloid. 



The residuijim still comported itself like the pure metal* 



^ See Jottrnal, vo\. XXIV, p. 38 • 



loid 



