328 SMITHSONIAN IMISCELLANEOUS COLLECTIONS VOL. 54 



BISMUTH. 



Early in tlie last century the combining weight of bismuth was approxi- 

 mately fixed through the experiments of Lagerhjelm.' Effecting the 

 direct union of bismuth and sulphur, he found that ten parts of the metal 

 yield the following quantities of trisulphide: 



12.2520 

 12.2065 

 12.2230 

 12.2465 



Mean. 12.2320 



Hence Bi = 215 in round numbers, a value now known to be much too 

 high. Lagerhjelm also oxidized bismuth with nitric acid, and, after igni- 

 tion, weighed the trioxide thus formed. Ten parts of metal gave the 

 following quantities of BioOg : 



11.1382 



11.1275 



Mean, 11.13285 



Hence Bi = 211.85, a figure still too high. 



In 1851 the subject of the atomic weight of bismuth was taken up by 

 Schneider,^ who, like Lagerhjelm, studied the oxidation of the metal 

 with nitric acid. The work was executed with a variety of experimental 

 refinements, by means of which every error due to possible loss of mate- 

 rial was carefully avoided. For full details the original paper must be 

 consulted; there is only room in these pages for the actual results, as 

 follows. The figures represent the percentages of Bi in BuO^ : 



89.652 

 89.682 

 89.644 

 89.634 

 89.656 

 89.666 

 89.655 

 89.653 



Mean, 89.6552, ± .0034 

 Hence Bi = 208.05. 



' Annals of Philosophy, 4, 358. 1S14. Adopted by Berzelius 

 - Poggend. Annalen, S2, 303. 1851. 



