300 THE ATOMIC WEIGHTS. 



Parpureo-cobalt chloride, C 



Salt. Co. Percent. Co. 



9472 .2233 23.575 



.8903 .2100 23.587 



.6084 .1435 23.586 



.6561 .1547 23.579 



.6988 .1647 23.569 



.7010 .1653 23.581 



Mean, 23.5795, .0019 

 The last series may be combined with Sommaruga's, thus : 



Sommaruga 23.817, .006 



Lee 23.5795, .0019 



General mean 23.6045, .0018 



Baubigny's * determinations of the atomic weight of nickel are limited 

 to two experiments upon the calcination of nickel sulphate, and his data 

 are as follows : 



6.2605 grm. NiSO 4 gave 3.9225 NiO. 48.279 per cent. 



4.4935 " 2.1695 " 48.281 



Mean, 48.280 



Zimmermann's work, published after his death by Krtiss and Alibe- 

 goff,f was based, like Russell's, upon the reduction of cobalt and nickel 

 oxides in hydrogen. The materials used were purified with great care, 

 and the results were as follows: 



* Compt. Rend., 97, 951. 1883. 

 f Ann. der Chem., 232, 324. 1886. 



