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E. DIVEKS AXb T. HAGA 



and the solution largely diluted. In the cold, barium nitrate in bare 

 excess, precipitates 4o per cent, of the sulphur as (very impure) 

 sulphate and sulphite, the estimation being based ou the quantity of 

 barium nitrate used, not upon that of the precipitate. When from 

 the acidified solution sulphur dioxideis rapidly blown out by a current 

 of air, the precipitate, obtained by bare excess of barium nitrate, shows 

 by its weight, after purification, that 12^ per cent, of the sulphur is 

 obtained as sulphate. But whether sulphur dioxide has been expelled 

 or not, and whether the solution is alkaline, neutral, or acid, the 

 standing with more barium nitrate gives much more sulphate, aud, 

 after removal of amidosulphonic acid by mercuric nitrate, still more 

 barium sulphate slowly deposits. The sulphate later precipitated is 

 not formed by hydrolysis of some compound, for that would be ac- 

 companied with acidification, whereas a neutral solution depositing 

 sulphate remains neutral. The difficulties due to the presence of 

 amidosulphonate, as well as sulphite, are, no doubt, not insuperable, 

 but, for the present, we are not prepared with a closely approximate 

 determination of the quantity of sulphate present. We can assert that 

 it is produced in a quantity between the limits of 12 and 20 per cent, 

 of the total sulphur, an important fact enough. 



Sulphite. — We have measured by iodine the sulphite formed in 

 the reduction of the nitrososulphate, and found it equal to 31 per cent, 

 of the sulphur. The actual determination gave no difficulty, but the 

 previous neutralisation with so much dilute sulphuric acid as was 

 necessary, and the other unavoidable slight exposure to air in preparing 

 the solution, must have reduced the quantity of sulphite, and it would 

 he unjustifiable refinement to assert more than that about one-third of 

 the sulphur becomes sulphite. Hydrazine acts slowly upon iodine 

 solution, but the solution used for the determination had been deprived 

 of all hydrazine by prolonged treatment with the amalgam. Accord- 



