Beliaviour of Chemical Compounds. 281 



In the investigation of the powdered solid salts simulta- 

 neously with the solution of the ferric nitrate in the flat glass 

 vessel, there was obtained for 



G. M. «. 



Potassium chromicyanide 0*5 11 2800 42-7 



„ ferricyanide O'GOG 1120 15*4 



Ferric nitrate .* 0-918 1105 100*0 



Potassium chromisulphocyanide 0*2525 2825 41*1 



Solution ofnormal ferric chloride 0*1226 3095 100*0 



According to this the magnetism of the chromium in the 

 potassium chromicyanide (42*7) and in the potassium chromi- 

 sulphocyanide (41*1) is nearly the same as that of the rest of 

 the chromic-oxide salts (41*9) ; there is no such diminution of 

 it to be perceived as that which is conditioned by the atomic 

 grouping belonging to the ferricyanide. We should hence be 

 justified in considering the potassium chromicyanide and 

 chromisulphocyanide simple double salts in which chromium 

 possesses quite the same properties as in solution of chromic 

 chloride, for instance, &c. 



17. Of great interest is the magnetic deportment of a series 

 of ammoniacal com2?oimds of cobalt, nickel, chromium, and cop- 

 per. As is known, chemically the so-called ammonio-cobalt 

 salts behave differently from the ordinary salts of cobalt ; and 

 one is inclined to assume that in them the cobalt occupies the 

 place of a part of the hydrogen of the ammonium. Other 

 ammoniacal compounds of cobalt, e. g. the double salt am- 

 monio-cobaltous sulphate &c., on the contrary, range them- 

 selves perfectly with the ordinary cobalt-salts. The same dif- 

 ferences are shown also in the magnetic behaviour of the 

 various cobalt compounds ; and the latter is accordingly 

 adapted, in doubtful cases, to decide concerning their consti- 

 tution. 



Nearly the same molecular magnetism is possessed by the 

 double salts ammonio-cobaltous sulphate &c., and by the am- 

 moniacal compounds obtained by passing gaseous ammonia 

 over anhydrous cobaltous sulphate, cobaltic chloride, &c., as 

 by the ordinary oxygen and haloid salts of cobalt. Thus, after 

 deducting the magnetism of the glass tilled with water, retain- 

 ing the previous notation, there was found: — 



G. M. oc. 



CoS04 + (NH4)oS04 + 6aq ... 0*4678 Co 86*6 73*0 



C0SO4 + 6NH3 0*1439 Co 22*3 64-7 



Normal ferric chloride 0*1226 Fe 30*9 100 



More or less deviating from this is the behaviour of those 



