PEROXYLAMINESULPHOS \ ES AND BYDROXYLAMINETRI8ULPHONATES. 23 



similar as he asserts. Secondly, certain striking contrasts may be 

 observed in the chemical character of the two solutions. Potassium 

 peroxylaminesulphonate is produced by the action of lead peroxide 

 and is not attacked by it, whereas the coloured acid solution is at 

 once oxidised by lead peroxide. Conversely, whilst this acid solution 

 is indifferent towards sulphur dioxide and produced by it, potassium 

 peroxylaminesulphonate is at once changed by this reagent. 



Then, again, it has not proved to be possible to convert 

 potassium peroxylaminesulphonate into this violet acid solution or to 

 effect the opposite change. Mr. S. Sekiguchi, a Post-graduate of 

 this University, has kindly carried out some experiments in this 

 direction. Making the mixtures very gradually and keeping them 

 • ■«»Id by ice and salt, he has poured the solution, prepared from 

 nitrososulphuric acid and sulphur dioxide in sulphuric acid, into a 

 solution of potassium hydroxide ; and, on the other hand, an aqueous 

 solution of potassium peroxylaminesulphonate into some concentrated 

 sulphuric acid ; in both cases, an almost immediate disappearance of 

 the violet colour results. In the former case, too, the alkaline 

 solution was evaporated and crystallised, without finding any of the 

 hvdroxylaminetrisulphonate which would result from the decomposi- 

 tion of peroxylaminesulphonic acid and might, to some extent, in 

 accordance with its usual stability, escape decomposition. 



Details of Experiment*. 

 The Exhaustive Action of Lead Peroxide ou Hydroxylaminesuiphonates. 

 2 3-normal potassium hydroxylaminedisulphonate was boiled 

 with excess of lead peroxide in about 15 times its weight of water, 

 containing from 1/5 to 2/5 of a molecule of potassium hydroxide, 

 until the solution had again h scome colourless. To the cold filtrate, 

 just enough barium acetate was added, to precipitate all sulphate 



