34 akt. is.-tamemasa haga. 



agnin 5 c.c. were taken out, the temperture being then 3°. The two 

 portions were each weighed and the amount of dissolved salt ascertain- 

 ed by n sulphur determination, rt was thus found that 0*l63gram of 

 salt was dissolved in 5'03 grams of its alkaline solution at 29°, and 

 that 0"027 gram was dissolved in 4'98 grams of its solution at 3°. 



Interaction of Potassium Peroxylaminesulplionate and Normal Potas- 

 sium. Sulphite — To a solution of 3.6 grams of potassium peroxylamine- 

 sulplionate, containing a very small quantity of potassium hydroxide, 

 a solution of normal potassium sulphite (neutral to Phenolphthalein) 

 was added from a burette, with constant stirring, until the violet 

 colour of the solution was entirely discharged. The change took 

 place quickly but not instantly. The quantity of sulphite required 

 was only a little more than that indicated by theory. After a short 

 interval, baryta water was added to precipitate the excess of sulphite 

 and the hvdroxylaminedisulphonate. The excess of baryta was 

 removed from the filtered solution by carbon dioxide and the filtered 

 solution evaporated so as to get out as much as possible of the 

 sparingly soluble potassium hydroxylaminetrisulphonate. Some more 

 of this salt was precipitated by adding twice the volume of alcohol and 

 leaving the mixture for some time. The total trisulphonate thus sepa- 

 rated weighed 2*268 grams, or 81*5 per cent, of the calculated quantity. 



The barium precipitate was triturated in a mortar with very 

 dilute acetic acid, added very slowly so as to avoid as far as possible 

 having any local excess of acid. When the solution had become 

 neutral to Phenolphthalein, the undissolved barium sulphite was 

 filtered off. Potassium carbonate in slight excess was added and the 

 whole left to stand for a day. Then, the solution, filtered from the 

 barium carbonate and neutralised with acetic acid, was concentrated 

 in a vacuum over sulphuric acid and mixed with twice its volume of 

 alcohol. In L 2 hours, the quantity of precipitated crystalline 2/3- 





