NICKEL AND COBALT. 17o 



chloride was also carried out. In order to avoid admixture 

 of carbon in the metallic residues,, the salts were first ignited 

 in air, and then in oxygen. Reduction by hydrogen fol- 

 lowed. The salts were in each case covered by a porous 

 septum of earthenware, through which the hydrogen dif- 

 fused, and which served to prevent the mechanical carrying 

 away of solid particles ; furthermore, heat was applied from 

 above. The results attained were very satisfactory, and 

 assign to nickel and cobalt atomic weights varying from 

 each other by about a unit; Ni being nearly 58, and Co 

 about 59. The exact figures will appear later. The cobalt 

 results agree remarkably well with those of Weselsky. The 

 following are the percentages of metal found : 



In brucia nickelocyanide. Ni,C\\.y{C.y^H.^^N.fi^^H^.ioH<^0. 



5-724 

 5-729 

 5-750 

 5-733 

 5-712 



5-729 



Mean, 5.7295, ± .0034 



In strychnia nickelocyanide, Ni^Cyy^{C ^-^^H ^^N.^^O^^.H ^.8 H ^O . 

 6.607 

 6.613 

 6.589 

 6.607 

 6.561 



6-595 



Mean, 6.595, i .005 



In brucia cobalticyanide, Co.^Cy^.^iC^-^H.^f^N'.^O^g.II^. 30 11.^0. 



3-759 

 3.720 



3-739 

 3-748 

 3-747 

 3-749 



Mean, 3.7437. ± -0036 



