178 



New Phenomena in Chemistry. 



harder and more brittle than any of the preceding are 

 often readily oxidized. This combination action separates 

 the alloys of mercury from all other alloys, so far as we 

 now understand them; for, as I have already shown, 

 instead of the mercury always losing power as a metal 

 solvent in proportion as it becomes alloyed — it shows a 

 preference, — and when combined with portions of the 

 readily oxidizable metals, becomes more active and indeed 

 almost ferocious in its appetite for the metals and alloys 

 that are of a highly electro-negative character; while if 

 alloyed with sufficient gold or silver in the first instance, it 

 appears satisfied, phlegmatic and indifferent to further 

 metallic food. Experiments which I have made demon- 

 strate that cyanide of potassium does not answer as well as 

 the amalgams of the alkaline metals, in effecting the union 

 of mercury with electro-negative metals, as some have 

 asserted. Its solution is indeed not more effective than 

 aqua-ammonia in producing such results, and what efficacy 

 either of these solutions possess, may be attributed to their 

 cleansing the surface of the metal to be amalgamated. 



It now becomes evident that the separation of metals 

 into the two classes is incorrect, as we have here, as in 

 every other general classification in science, no absolute 

 division, but merely extremes and means; the true mean 

 being difficult to determine. The reactions of these amal- 

 gams of the electro-positive metals with those metals 

 which are relatively electro-negative, are very instructive. 

 They tend to prove that all the amalgams subsequently 

 formed are the results of electrical action, to induce which 

 we have only to place a particle of iron in contact with 

 potassium amalgam and with water. In an instant we 

 have a voltaic battery in active operation ; the amalga- 

 mated potassium forming the "zincode," while the iron is 

 the electro-negative element of the battery. Of the metals 



