276 ZINC. 



When Professor E. F. Smith, in 1899, (Journal American 

 Chemical Society, 1899, p. 1022), concludes, " it is evident 

 " that no reliable atomic mass determinations can be made 

 u by the oxidation of metallic tungsten " we may agree, if 

 he means the atomic "weight, we have really used reduction 

 results, only. 



But his reason stated looks very insufficient; (1. c., p. 

 1022). We need only put it into plain form, in milli- 

 grammes. We find a loss of i.o per process, a round and 

 it is no doubt due to the oxidation part of the round. 



For these and other reasons we must decline to con- 

 sider the work of Smith and his students of any value in 

 comparison to the work summarized in our first group, done 

 by known and proved masters. 



There is one other reason, which I have not stated, and 

 which others cannot as fully appreciate as I have learned to 

 do. It is the high praise from Clarke, see page 259 

 (extremely low probable error) ; p. 260. (P. and S. vastly 

 outweighs everything else) ; p. 263 (work in Smith's labora- 

 tory dominates all the rest). 



Knowing, by long experience, that Clarke's opinion, 

 being based on a false formalism, is not only worthless, but 

 invariably on the side of error, I see this, my opinion, 

 most strikingly verified in this instance. 



If there is a case in which this author of weighing and 

 judging chemical work is right (Clarke), I should be 

 delighted to have it pointed out to me. 



Zn = 65. ZINC. AXEL ERDMANN, 1844. 



Zn : Zn Orrr 65 : 81 =0.80 247. Change 24 high. 

 Jacquelin, 1842: 



Wet way, 4 Det., 570 524; 46. Mean 296 high. 

 Axel Erdmann, 1844; 



Dry way, 4 Det, 274 247; 27. " 13 high. 

 Morse and Burton, 1888: 



15 Det., 320 305; 15. u 65 high. 

 Recent work on absorption of oxygen by the oxide, has 

 not been sufficiently studied, not having had access to the 

 details. 



