ATOMIC WEIGHTS 247 



For the ratio 3Ag: Cd Hardin foimd the value 51. 876, ±.0041. Meag- 

 lia's series gives 52. 090, ±.0136. The general mean of both series com- 

 bined is 



2Ag:Cd: : 100: 51.893, ± .0039 



The determinations made by Blum ^ depended npon the conversion of 

 CdO into CdS by heating in a stream of hydrogen sulphide. His figures, 

 with vacuum weights, are given below, together with the ratio CdO : 

 CdS::100:.r.- 



CdO. CdS. Ratio. 



1.80552 2.03108 112.493 



.66349 .74617 112.461 



1.82460 2.05256 112.494 



1.88424 2.11974 112.498 



3.59206 4.04081 112.493 



4.38093 4.92095 112.464 



Mean, 112.484, ± .0046 



Hence Cd = 112.69. This ratio is not of much value. 

 For cadmium the subjoined ratios are now available. 



Bucher's single experiment upon the synthesis of the sulphate, although 

 important and interesting, cannot carry weight enough to warrant its 

 consideration in connection with the other ratios, and is therefore not 

 included. 



(1). CdO:Cd::100:87.536, ± .0002 

 (2). CdaO^rCdO: : 100: 63.966, ± .0010 

 (3). CdCA:CdS: :100:71.974, ± .0007 

 (4). CdSO,:CdS: :100:69.202, ± .0012 

 (5). 2Ag:CdCU: : 100: 84.9676, ± .0008 

 (6). 2AgCl:CdCl,: : 100: 63.9518, ± .0004 

 (7). 2Ag:CdBr,: :100:126.178, ± .0009 

 (8). 2AgBr:CdBr,::100:72.4813, ±.0005 

 (9). CdCL:Cd: :100:61.244, ± .0010 

 (10). CdBr„:Cd: : 100: 41.203, ± .0010 

 (11). 2Ag:Cd::100:51. 893, ±.0039 

 (12). Au:Cd: : 197.2: 112.461, ± .0196 

 (13). CdO : CdS :: 100: 112.484, ± .0046 



Eeducing these ratios with 



Ag =: 107.880, ± .00029 S = 32.0667, ± .00075 



CI = 35.4584, ± .0002 C = 12.0038, ± .0002 



Br = 79.9197, ± .0003 An = 197.269. ± .0030 



Thesis, University of Pennsylvania, 190S. 



