ANTIMONY. 265 



See True Atomic Weights, 1894, p. 98. Series I of Cooke, 

 highly concordant, but greatly in error, because silver lost 

 by volatilization, as Cooke found himself. He instituted the 

 third series under special conditions, avoiding such loss; 

 hence he properly rejected Series I, as we do, and retained 

 III only. The second series was also rejected, for same 

 reasons; in third series reduction took place without visible 

 glow. 



We should have stated, that Dumas and Stas operated by 

 actual synthesis, while Cooke reduced pure sulphide in a 

 current of hydrogen. 



Ag2 : Ag2 O4 S 216 : 312=0.69 231. Chg. 20 high. 

 Struve, 1851, 6 Det., 244 212; 32. Mean i low. 



Stas, 1865, 6 Det., 209 197; 12. " 28 low. 



Both series were reductions in a current of hydrogen. 

 Struve used from 5 to 12 grammes of Sulphate, Stas from 56 

 to 83 grammes. The observations of Cooke explain the 

 difference in the results. 



I do not think there will remain a single result of all the 

 much lauded work of Stas after ten years. 



Sb = 120. ANTIMONY. SCHNEIDER, 1856. 



Sa : Sba Sa =96 : 336 = 0.28 571. Chg. 16 low. 

 Schneider, 1856, 8 Det., 559 481 ; 78. Mean 51 low. 

 Cooke, 1877, ii Det., " 53 low. 



Schneider, 1880, 3 Det., 546 534; 12. " 30 low. 



Schneider reduced pure, crystallized Stibnite, from Arns- 

 berg; minute impurities of Ca Carbonate and Fe Sulphide 

 were allowed for. Cooke's work was synthetic, in wet way 

 mainly. Schneider's last value represents 120.2. 



The work is very difficult. 



While reading the final proof I received from Professor 

 Edgar F. Smith his recent determinations made by heating 

 tartar emetic, dried at 150, in a current of dry muriatic 

 acid, leaving pure potassium chloride. How the carbon is 

 disposed of, need not here be stated, except that evidently a 

 slight loss of the chloride can hardly be avoided; hence we 

 expect the analytical ratio to come out low. 



