ATOMIC WEIGHTS 



95 



Ag. 



4.6240 

 6.39978 



Agl. 



10.0634 

 13.92913 



Ratio. 



117.6340 

 117.6502 



Mean, 117.6421, ± .0054 



Koethner and Aeuer/ who also studied what might be called the Laden- 

 burg ratio, succeeded in proving the occlusion of silver nitrate by silver 

 iodide, to which allusion has already been made. They effected two 

 syntheses of silver iodide, however, avoiding this error, and by two 

 methods. First, silver iodide was precipitated from solution with pure 

 hydriodic acid. Secondly, silver was directly combined with iodine, by 

 heating in a stream of iodine vapor. The two syntheses are subjoined, 

 with the ratio stated in the form Ag : Agl, and the weights corrected to 

 a vacuum : 



Mean, 217.6413, ± .0045 



The very thorough and careful experiments by Baxter " fall into several 

 series, and represent several distinct methods of procedure. First, pure 

 silver was converted into nitrate, and precipitated by a solution of am- 

 monium iodide in presence of an excess of ammonia. All weighings in 

 Baxter's experiments were reduced to a vacuum standard, and various 

 minor corrections were applied, concerning which the original memoirs 

 must be consulted. Two series of determinations are given, as follows : 



Ag. 

 5.23123 

 3.57039 

 4.60798 

 4.52467 

 4.66256 



Freliminary Series. 



.0059 



' Liebig's Annalen, 337, 123. 1904. 



=^Two memoirs. First, Proc. Amer. Acad., 40, 419. 1904. Second, ibid., 41, 73. 1905. 



