126 THE ATOMIC WEIGHTS. 



And for barium itself, four values are finally available, thus : 



From molecular weight BaClj Ba = 136. 271, zh .0106 



From molecular weight BaBr.^ " = 136.390, ± .0141 



From ratio (5) " = 135.600, rh .2711 



From ratio (6) " = 136.563, ± .0946 



General mean Ba = 136.315, rb .0085 



Or, if = 16, Ba = 137.354. 



In the foregoing computation all the data, good or bad, are included. 

 Some of them, as shown by the weights, practically vanish ; but others, 

 as in the chloride series, carry an undue influence. A more trustworthy 

 result can be deduced from Richards' experiments alone, which reduce 

 as follows : 



From Ag., : BaClj BaCl^ = 206.761, =h .ooSo 



From 2AgCl : BaClj " = 206.754, i .0067 



General mean BaClj = 206.755, — -OOSI 



From the bromide, as given above, Ba = 136.390, ± .0141. From the 

 value just found for the chloride, Ba =: 136.397, ±: .0109. Combining 

 the two values — 



Ba ^= 136.392, =b .0086. 



Or, if = 16, Ba = 137.434. This determination will be adopted in 

 subsequent calculations as the most probable. 



