12 ART. 13. T. HAG A : 



which resisted hydrolysis at 150°C,, was not determined, owing to loss 

 during the analysis. These results will be discussed later (p. 15). 



The Quantity of Sulphur Dioxide which enters into Reaction 

 with Bihenzenesulphohydfoxylamine : — This was only roughly esti- 

 mated in two experiments and in the following manner. Diben- 

 zenesulphohydroxylamine was dissolved in about six times its 

 weight of approximatly ninety per cent alcohol and treated with 

 sulphur dioxide, until the increase in weight was about four-fifths 

 of the weight of the oxime taken. After leaving the whole in a well 

 stoppered bottle for two days, the excess of sulphur dioxide was 

 blowni ofP by a current of air passed through the liquid. In the 

 one experiment, the total sulphur iu the solutiou was determined 

 as sulphate by evaporating off the alcohol, oxidising the residue 

 by means of strong nitric acid and fusing the mass with potassium 

 hydroxide and nitre. In the other experiment this was done by 

 neutralising the solution with potassium hydroxide, evaporating 

 the whole to complete dryness, reducing the residue to fine powder, 

 mixing it wdtli about eight times its weight of dry sodium 

 carbonate in a platinum crucible, and roasting it very gradually 

 with a layer of dry sodium carbonate placed over the mixture. 

 In both cases, all the sulphur was converted into the alkali 

 sulphate. This was precipitated as barium sulphate and weighed. 

 The results were practically identical. By subtracting the sulphur 

 of dibeuzeuesulphohydroxylamine from the total sulphur thus 

 found the quantity of sulphur dioxide fixed by the reaction was 

 estimated. The result showed that, even when the sulphuric 

 acid due to the aerial oxidation of sulphur dioxide was included, 

 its quantity was decidedly less than corresponds to one molecule 

 of it for every molecule of tlie dibenzenesulphohydroxylamine 

 reduced, it being only 82.6 per cent of the calculated quantity. 



I 



