286 THE ATOMIC WEIGHTS. 



16.0029 g'"f"- M'lSO^ gave 9.2228 Mn.S = 57.632 per cent. 

 16.3191 " 9.4048 " 57-631 



15.9307 " 9.1817 " 57-634 " 



15.8441 " 9-1315 " 57.634 " 



16.2783 " 9-3819 " 57-635 " 



17.0874 " 9-8477 " 57-633 " 



Mean, 57.633, ± .0004 

 von Hauer found, 57.608, ±: .0080 



Hence the general mean is identical with Weeren's to the tliird deci- 

 mal place, which is unaffected by combination with von Hauer's data. 

 We have now to consider the following ratios for manganese: 



(i.) 2AgCl : MnClj : : 100 : 41.924, dr .0150 



(2.) 2Ag : MnCl2 : : loo : 58.321, zh .0010 



(3.) H.p : Mn^O, : : 100 : 1255.82, ± .340 



(4.) 2CO2 : Mn : : lOO : 61.3943, rt .0122 



(5.) AgMnO^ : Ag + MnO : : 100 : 78.835, ± .0174 



(6.) KBr : AgMnO^ : : 100 : 190.584, =t .0062 



(7.) MnSO^ : MnO : : 100 : 47.004, =h .0006 



(8.) MnSO^ : MnS : : 100 : 57.633, dt .0004 



Computing with the subjoined preliminar}^ data — 



O = 15.879, it .0003 K = 38.817,^.0051 



Ag = 107.108, zb .0031 C ^ 1 1.920, ± .0004 



CI ^ 35.179, ± .0048 S = 31.828, i .0015 



Br = 79.344, ± .0062 AgCl ^ 142.287, zfc .0037 



these ratios reduce as follows : 



First, for the molecular weight of manganese chloride, two values are 

 deducible. 



From (1) MnCl^^ 124.996, zh .0428 



From (2) " = 124.933, zfc .0042 



General mean MnCl^ =■ 124.934, zfc .0042 



Hence Mn = 54.576, ± .0075. 



For manganese there are seven indejjendent values, as follows : 



From molecular weight MnCl.^ Mn = 54.576, zfc .0075 



From (3) " =53.667, zfc .0203 



From (4) " = 53-633, ± -0107 



From (5) " =54.450, ±.15" 



From (6) " = 54-572, ± .0173 



From (7) " = 54.601, zfc .0018 



From (8) " = 54-575, ± -0022 



General mean Mn = 54.571, zfc .0013 



If = 16, this becomes Mn = 54.987. 



In this case five of the separate values are well in accord, and the re- 

 jection of the two aberrant values, which have high probable errors, is 



