,f 10 Preiich National Instiivte. 



The acli;>ii or the metal of the potash on the oxltlcs and 

 the inetalhc sahs, and on the eavlhy and alkahne sails, has 

 also been particularly examined bv Messrs. (Jay Lvissac 

 tnd 'I'henard. It results iVoni their inquiries, that all the 

 bodies in which we know (he presence of oxvgen are de- 

 composed by this metal ; that this dccompf)sifion almost 

 always takes place with an extrication ollightand heat ; that 

 this extrication is the more considerable in proportion as 

 the oxvgen is less condensed ; and that, consequently, this 

 might furnish a method of appreciating the degree of con- 

 densation of the oxygen in any body. 



After having operated on potasli antJ soda, by means of 

 the Voltaic pile, the charges mentioned in the early part 

 of this memoir, it was natural to endeavour to produce 

 analogous efleets on the other alkalis, and on the earths. 

 Jn short, ]\ir. Davy undertook numerous experiments, in 

 order to discover, aceordino- to his svstem, the metals of 

 bnrytes, strontian, lime, magnesia, silcx, alumine, zircon, 

 and glucine. After several fi'uitless eflbrts, he succeeded 

 in de-oxy>:;enizing the first four of these substance^, and in 

 forming amalgams of the new metals which resulted. He 

 thinks that the other four are also metallic oxides ; but 

 his experiments, as he confesses, do not prove this in a 

 satisfactory nianner. 



Another amalgam produced by an>monia was dis- 

 covered last year, at .Jena, by Dr. Sceheck. This after- 

 wards became the subject of certain researches bv 

 Messrs. Berzclius and Ponlin of Stockholm, and by 

 Mr. Davy in England : all three agree in ascertaining am- 

 monia to be a metal. In the ordinary temperaluje of the 

 atmosphere this amalgam has the consistence of butter, and 

 in the cold it crystallizes in cubes ; but the new metal has 

 not yet been obtained in a separate state. Messrs. Gay 

 I.ussac and Thenard have repeated and proved the correct- 

 ness of the above experiments. But this amalfram, which 

 had been formed by the action of the pile onfy, has been 

 produced by the French chemists by the action of the 

 metal of potash, and they have a>ceriained that a slight 

 agitation was sufficient to decompose it. By this simple 

 actit;n the mercurv once more becomes tluid, and ammonia 

 and hydrogen are liberated in the proportion of 2S to 23. 

 The mercury absorbs 141 times its volume of hydrogen 

 gas, and 88 limes ils volume of anuTjoniacal gas, in order 

 to pass to the state of amalgam : whence it results, according 

 to our authors, that in this combination the mercury in- 

 'creases about 0*0007 of its weight ; v.hereasj accordin<]: to 



Mr. 



