ANTIMONY. 199 



3.2838 grm. SbBrj gave 5.1398 grm. AgBr. 63.890 



2.3589 " 3-6959 " 63.S25 



1.3323 " 2.0863 " 63.859 



2.6974 " 4-2285 " 63.791 



Mean, 63.830, d= .008 



The iodide of antimony was prepared like the bromide, 

 and analyzed in the same way. At first, discordant results 

 were obtained, due to the presence of oxyiodide in the iodide 

 studied. The impurity, however, was removed by sublim- 

 ing the iodide in an atmosphere of dry carbon dioxide. 

 With this purer material; seven estimations of iodine were 

 made, giving, if Ag = 108 and I = 127, a value for anti- 

 mony of Sb = 120. Reduced to a uniform standard, Cooke's 

 weighings give the following quantities of Sbig proportional 

 to 100 parts of silver iodide : 



1. 1877 grm. Sblj gave 1.6727 grm. Agl. 71.005 



.023 



Although Cooke's work was practically conclusive, as 

 between the rival values for antimony, his results were 

 severely criticized by Kessler,* who, evidently, had read 

 Cooke's paper in a very careless way. On the other hand, 

 Schneider published in Poggendorff's Annalen a friendly 

 review of the new determinations, which so splendidly vin- 

 dicated his own accuracy. In reply to Kessler, Cooke un- 

 dertook still another series of experiments with antimony 

 bromide,t and obtained absolute confirmation of his pre- 

 vious results. To a solution of antimony bromide was 

 added a solution containing a known weight of silver not 

 ■quite sufficient to precipitate all the bromine. The excess 



*Berichtecl. Deutsch. Chem. GeselL, 12, 1044. 1879. 



f Amer. Jouni. Sci. and Arts, May, 1880. Bcrichte, 13, 951. 



