The Atomic Weight of Japanese Tellurium. 



By 

 Masumi Chikashige, Rigakushi, 



College of Science, Imperial University. 



The atomic weight of tellurium has been determined by Berzelins 

 (1833), von Hauer (1857), Wills (1879), Brauner (1883 ; 1889), and 

 Staudenmaier (1895). Berzelius gave it as 128*3 (0 = 16). Stauden- 

 maier has only reduced it to 127*6. Brauner had also obtained this 

 number, that is, 127*64, by determining the quantity of bromine in 

 the tetrabromide ; but in other ways, which he could not admit to be 

 naccurate, he obtained widely varying numbers for the atomic weight. 

 To explain these variations, he assumed that what passes for the element 

 tellurium is a mixture or compound. The number, 125, which since 

 1884 has been generally accepted as the atomic weight of tellurium, 

 was suggested by Mendeleeff, but was adopted on the grounds of 

 Brauner's determinations (partly by faulty methods, as he has since 

 ascertained) published in 1883 in Russia. A paper by him, on the 

 atomic weight of tellurium, which appeared last year in the Journal 

 of the (London) Chemical Society, supplies no new data. It throws no 

 light upon the causes of the varying results he had previously obtained 

 by different methods, but apparently contains the admission from him 

 at last that, so far as can be determined by known methods, the 

 atomic weight of tellurium is 127*64 (127*7 in vacuo). 



The object of the research described in the present communica- 

 tion to this Journal has been, not to add one more to the above 



