1 00 Mr. Grove on some Electro-Nitrosnirets. 



5' 



electrolysis differed somewhat from that of zinc ; with the latter 

 metal the solution was during the whole time perfectly trans- 

 parent, and no precipitate formed ; with cadmium, after a 

 short time, the hydrated oxide was precipitated by the ammonia 

 formed at the cathode ; but the portions of this precipitate 

 contiguous to the cathode, being redissolved by excess of 

 ammonia, were revived by the voltaic current ; the sponge 

 formed very rapidly; its growth could be distinctly seen; it was 

 of a very dark leaden gray approaching to black, and resem- 

 bled very closely the mercurio-ammoniacal amalgam ; it had 

 not the semi-crystalline appearance of the zinc sponge, but 

 when pressed between glass had a leaden lustre and very 

 much the appearance of an amalgam; if left in the solution, it 

 was observed to contract and acquire a lighter shade of co- 

 lour, most probably from the reaction of dissolved chlorine ; 

 the portions to be examined were, therefore, removed in- 

 stantly and plunged into distilled water. The specific gravity 

 was 4-8, analysed in the same way with the product from zinc ; 

 four experiments gave of permanent gas, 



Cubic inches. 



1 0'25 



2 0-18 



3 0*20 



4 0-20 



4)-83 



Mean .... -207 

 This gas, however, when examined, proved to contain no 

 hydrogen ; the residue in the tube was of a yellowish green 

 colour mixed with globules of distilled cadmium. 



Copper subjected to similar electrolysis produced a bright 

 blue transparent solution, in which, at the cathode, grew a 

 beautiful purple or rather chocolate-coloured coagulum ; this 

 frequently, but not always, floated upon the liquid ; its specific 

 gravity was 5*9. Five grains, when heated, gave of permanent 

 o-as. Cubic inches. 



0-13 



o-io 



0*09 

 0-11 



4) '43 



•107 

 This gas also contained no hydrogen, but was wholly nitrogen; 



