170 THE ATOMIC WEIGHTS. 



We now have six ratios involving the atomic weight of mercury, as 

 follows : 



(i.) Per cent, of Hg in HgO, 92.595, .0003 



(2.) Per cent, of Hg in HgS, 86.2127, =b .0027 



(3.) Per cent, of Hg in HgCl a> 73.826, .0011 



(4.) Per cent, of Hg in HgBr 2 , 55.556, .0012 



(5.) Per cent, of Hg in HgC 2 N 2 , 79.339, .0004 



(6.) 2Ag : Hg : : 100 : 92.660, .0051 



The calculations involve the following values : 



O = 15.879, -.0003 Br=r 79.344, .0062 



Ag= 107.108, .0031 S =31.828, .0015 



Cl = 35.179, .0048 C = 11.920, .0004 



N = 13.935, .0021 



Hence the values for mercury are 



From (I) Hg = 198.557, .0084 



From (2) " = 199.027, H= .0406 



From (3) " = 198.482, .0285 



From (4) " = 198.364,^.0170 



From (5) 198.568, .0170 



From (6) " = 198.493, .0124 



General mean Hg = 198.532, db .0059 



If 0= 16, Hg = 200.045. 



But according to Hardin the value derived from the analyses of mer- 

 curic oxide is untrustworthy. Rejecting this, and also the abnormally 

 high -result from the sulphide series, the general mean of the four re- 

 maining values is 



Hg = 198.491, .0083, 



or, with = 16, Hg = 200.004. These figures seem to be the best for 

 the atomic weight of mercury. 



