88 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 54 



for silver and chlorine. In his work on titaninm bromide, intended to 



determine the atomic weight of titanium, Thorpe ' gives the following 

 equivalent weights of silver and silver bromide : 



Ag. AgBr. Ratio. 



3.66122 6.375391 74.133 



5.55097 9.663901 74.094 



8.17645 14.227716 . 74.008 



7.83493 13.639956 74.092 



Mean, 74.082, ± .0176 



Thorpe and Laurie ° compared gold with silver and silver bromide, 

 and give equivalent weights as follows : 



Ag. AgBr. Ratio. 



3.38451 5.89199 74.087 



2.60896 4.54261 74.113 



2.28830 3.98288 74.054 



2.26415 3.94309 74.153 



1.97147 3.43015 73.989 



2.01292 3.50207 73.980 



2.50334 4.35736 74.062 



2.93608 5.11045 74.057 



Mean, 74.062, ± .0143 



In Richards' ' memoir upon the atomic weight of barium, the sub- 

 joined vacuum weights of Ag and AgBr are given as equivalent to each 



other. Two additional determinations are rejected by Eichards as in- 

 accurate : 



Ag. AgBr. Ratio. 



1.71323 2.98230 74.075 



2.13584 3.71809 74.081 



1.52921 2.66191 74.071 



2.11740 3.68615 74.089 



1.72276 2.99868 74.063 



1.34175 2.33530 74.049 



4.11360 7.16120 74.086 



2.56010 4.45670 74.083 



2.51415 4.37669 74.082 



Mean, 74.075, ± .0029 



From the analyses of nickel bromide, by Richards and Cushman," the 

 following figures are derived. These, and all the subsequent series, repre- 

 sent vacuum weights : 



Mourn. Chem. Soc, 47, 126. 1885. 

 '■^ Journ. Chem. Soc, 51, 565. 1887. 

 s Proc. Amer. .\cad., 28, 1. 1893. 

 ••Proc. Amer. Acad., 33, 97. 1897. 



