ATOMIC WEIGHTS 315 



28.559 

 28.557 

 28.501 

 28.554 

 28.532 

 28.485 

 28.492 

 28.481 



Mean, 28.520, ± .008 



Hence Sb = 120.55. 



Immediately after tlie a|)pearance of Schneider's memoir, Eose ' pub- 

 lished the result of a single analysis of antimony trichloride, previously 

 made under his supervision by Weber. This analysis, if CI = 35.5, makes 

 Sb = 130.7, a value of no great vi^eight, but in a measure confirmatory of 

 that obtained by Schneider. 



The next research upon the atomic weight of antimony was that of 

 Dexter,' published in 1857. This chemist, having tried to determine 

 the amount of gold precipitable by a known weight of antimony, and 

 having obtained discordant results, finally resorted to the original method 

 of Berzelius. Antimony, purified with extreme care, was oxidized by 

 nitric acid, and the gain in weight was determined. From 1.5 to 3.3 

 grammes of metal were used in each experiment. The reduction of the 

 weights to a vacuum standard was neglected as being superfluous. From 

 the data obtained, we get the following percentages of Sb in Sb204 : 



79.268 

 79.272 

 79.255 

 79.266 

 79.253 

 79.271 

 79.264 

 79.260 

 79.286 

 79.274 

 79.232 

 79.395 

 79.379 



Mean, 79.283, ± .009 



Hence Sb = 122.46. 



The determinations of Dumas' were published in 1859. This chemist 



^ Poggend. Annalen, 98, 455. 1856. 

 -Poggentl. Annalen, 100, 363. 1857. 

 3 Ann. Chim. Phys. (3), 55, 175. 



