238 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 54 



In the third set of determinations cadmium oxalate was transformed 

 to sulphide by heating in H.S, giving the ratio CdCoO^ : CdS : : 100 : a;; 



CdC,0,. 

 1.57092 

 1.73G54 

 2.19276 

 1.24337 

 1.18743 

 1.54038 

 1.38905 

 2.03562 

 2.03781 

 1.91840 



CdS. 

 1.13065 

 1.24979 

 1.57825 



.89492 



.85463 

 1.10858 



.99974 

 1.46517 

 1.46658 

 1.38075 



Per cent. CdS. 

 71.972 

 71973 

 71.974 

 71.974 

 71.975 

 71.968 

 71.976 

 71.979 

 71.970 

 71.971 



Hence Cd = 111.61. Mean, 71.973, ± .0007 



This work of Partridge was presently discussed by Clarke/ with ref- 

 erence to the concordance of the data, and it was shown that the three 

 ratios determined could be discussed algebraically, giving values for the 

 atomic weights of Cd, S and C when = 16. These values are — 



Cd =111.7850 

 C = 11.9958 

 S = 32.0002 



and are independent of all antecedent values except that assumed for 

 the standard, oxygen, 



Morse and Jones,^ starting with cadmium purified by fractional distil- 

 lation in vacuo, adopted two methods for their determinations. Pirst, 

 they effected the s}mthesis of the oxide from known weights of metal 

 by dissolving the latter in nitric acid, evaporating to dryness, and subse- 

 quent ignition of the product. The oxide thus obtained was thought 

 to be completely free from oxides of nitrogen. The weighings, which are 

 given below, were made in tared crucibles. The third column gives the 

 percentage of Cd in CdO : 



Cd taken. CdO found. Per cent. Cd. 



1.77891 2.03288 87.507 



1.82492 2.08544 87.508 



1.74688 1.99626 87.507 



1..57000 1.79418 87.505 



1.98481 2.26820 87.506 



2.27297 2,59751 87.504 



1,75695 2.00775 87.508 



1.70028 1.94305 87.505 



1.92237 2.19679 87.508 



1.92081 2.19502 87.508 



Hence Cd = 112.068. 



Mean, 87.5066, ± .00032 



> Amer. Chem. Journ., 13, 34. 1S91. 

 ^.\mer. Chem. Journ., 14, 261. 1S92. 



