ATOMIC WEIGHTS 111 



Stas/ applying the method used in establishing the similar ratio for 

 potassium chloride, and working with salt from six different sources, 

 found of sodium chloride equivalent to 100 parts of silver : 



54.2093 



54.2088 

 54.2070 

 54.2070 

 54.2070 

 54.2060 

 54.2076 

 54.2081 

 54.2083 

 54.2089 



Mean, 54.2078, ± .0002 



As in the case of the corresponding ratio for potassium chloride, these 

 data needed to be checked by others which took into account the solu- 

 bility of silver chloride. Such data are given in Stas' paper of 1882,^ 

 and four results are as follows : 



54.2065 

 54.20676 

 54.2091 

 54.2054 



Mean, 54.20694, ± .00045 



Corrected for a trace of silica in the sodium chloride, this mean becomes 

 54.2047, ±.00045. 



The elaborate research of Kichards and Wells ' upon this ratio, gave 

 a lower value than that found by Stas. According to Eichards and 

 Wells, the silver used by Stas probably contained occluded oxygen, and 

 his silver chloride carried down occlusions of sodium salts. The new 

 data, with vacuum weights as usual, are as follows, the last two experi- 

 ments forming a small supplementary series : 



^ OeiuTes Completes, 1, 370. 



^ Oeuvres Completes, 1, 768, 773. 



3 Publ. Carnegie Inst., Washington, No. 28, pp. 52, 56. 1905. 



