292 THE ATOMIC WEIGHTS. 



NiC^0,.3H^0. 



1. 1945 grm. gave .528 grm. CO^. 44.203 per cent. 



2.5555 " I. 12625 " 44-072 " 



3.199 " 1.408 " 44.014 " 



5.020 " 2.214 " 44.104 " 



Mean, 44.098, zh .027 



The following percentages of nickel were found in this salt 



Mean, 47.7475, =t .0213 



The following were the percentages found for cobalt: 



32.552 

 32.619 

 32.528 

 32.523 



Mean, 32.5555, zb. 0149 



In a later paper* Schneider also gives some results obtained with a 

 nickel oxalate containing but two molecules of water. This gave him 

 47.605 per cent, of CO.^, and the following percentages of nickel: 



31.4115 

 31.4038 



Mean, 31.4076, ±.0026 



The conclusion at which Schneider arrived was that the atomic weights 

 of cobalt and nickel are not identical, being about 60 and 58 respectively. 

 The percentages given above will be discussed at the end of this chapter 

 in connection with all the other data relative to the constants in ques- 

 tion. 



- The next chemist to take up the discussion of these atomic weights 

 was Marignac, in 1858. f He worked with the chlorides and sulphates 



*Poggend. Annalen, 107, 616. 



t Arch, des Sci. Phys et Nat. (nouv. serie), i, 372. 185S. 



