434 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 54 



nickel. The latter was purified by distillation as nickel carbonyl, then 

 converted into oxide, and that was reduced by hydrogen in the usual 

 way. 



Mean, 78.545, ± .0061 



Hence Ki = 58.575. 



Schutzenberger's experiments,' published in 1892, were also few in 

 number. First, nickel sulphate, dehydrated at 440°, was calcined to 

 oxide. 



3..505 grm. NiSO^ gave 1.690 NiO. 48.217 per cent. 



2.0008 " 1.2561 " 48.297 



Mean, 48.257, ± .027 

 Hence Ni = 58.672. 

 Secondly, nickel oxide was reduced in hydrogen, as follows : 



1.6865 grm. NiO gave 1.3245 Ni. 78.535 per cent. 



1.2527 " .9838 " 78.533 



Mean, 78.534 



Hence ]Sri=: 58.536. 



In one experiment with cobalt oxide, 3.491 grm. gave 2.757 Co, or 

 78.975 per cent. Hence Co = 60.1. In view of the many determinations 

 of this ratio by other observers, this single estimation may be neglected. 

 The experiments on nickel sulphate, however, should be combined with 

 those of Marignac and Baubigny, giving the latter equal weight with 

 Schutzenberger's, thus : 



Marignac 48.287, ± .0675 



Baubigny 48.280, ± .027 



Schutzenberger 48.257. ± .027 



General mean 48.269, ± .018 



From this point on the determination of these atomic weights was 

 temporarily complicated by the questions raised by Kriiss as to the truly 

 elementary character of nickel and cobalt. If that which has been called 

 nickel really contains an admixture of some other hitherto unknown 

 element, then all the determinations made so far are worthless, and the 

 investigations now to be considered bear directly upon that question. 



» Compt. Rend., 114, 1149. 1892. 



