ATOMIC WEIGHTS 



91 



Ag. AgBr. Ratio. 



6.56765 11.43300 74.080 



4.83238 8.41206 74.077 



4.90354 8.53642 ^ 74.087 



5.65813 ■ 9.85008 * 74.087 



5.82600 10.14206 74.083 



3.61478 6.29271 74.083 



5.18711 9.02959 74.077 



3.94042 6.85968 74.085 



4.51250 7.85571 74.088 



3.61736 6.29740 74.088 



4.79620 8.34915 74.078 



3.59319 6.25569 74.098 



5.72G41 9.96840 74.078 



Mean, 74.084, ± .0011 



The incidental determinations of the silver-bromine ratio now com- 

 bine thus: 



Thorpe and Laurie, Au series 74.062, ± .0143 



Richards and Marigold, U series 74.073, ± .0027 



Richards and Baxter, Co series 74.074, ± .0033 



Richards, Ba series 74.075, ± .0029 



Richards and Cushman, Ni series 74.080, ±: .0030 



Archibald, Rb series 74.080, ± .0040 



Richards and Archibald, Cs series 74.081, ± .0017 



Thorpe, Ti series 74,082, ± .0176 



Baxter, Hines and Prevert, Cd series 74.084, ± .0010 



Baxter and Hines, Mn series 74.084, ± .0011 



General mean 74.082, dz .0006 



Several indirect determinations of the silver bromine ratio, as in the 

 case of the chlorides, are deducible from analyses of metallic bromides.' 

 In Cooke's determinations of the atomic weight of antimony, the 

 ratios are as follows: 



3Ag:SbBr3: : 100: 111.114, ± .0014 

 3AgBr:SbBr3: : 100: 63.830, ±: .008 



Hence Ag : Br : : 100 : 74.078, ± .0219. 



From Huntington's analyses of cadmium bromide we have- — 



2Ag:CdBr„: : 100: 126.076, ± .0052 

 2AgBr:CdBr,: : 100: 72.4216, ± .0028 



Hence Ag : Br : : 100 : 74.086, ± .0098. 



The work of Eichards on strontium bromide gives — 



2Ag:SrBr„: : 100: 114.689, ± .0012 

 2AgBr:SrBn: : 100: 65.884, ± .0006 



Hence Ag : Br : : 100 : 74.077, ± .0024. 



^ For details, see later sections of this work, on Sb, Cd, Sr, Zn, Cd, Fe, etc. 



