290 



DIVERS & HAGA; REDUCTION' OF XITROSOSULPHATES. 



memory of Pélouze. In the year 1800, thirty-five years before 

 Pélouze published his work on these salts, Davy made known that, 

 apparently, a combination of nitrous oxide with potash was obtainable 

 by subjecting a mixture of potassium-hydroxide and sulphite, 

 in the solid state, to the prolonged action of nitric oxide, dis- 

 solving the product in water, crystallising out potassium sulphate, 

 and evaporating the mother liquor to dryness. The residue was a 

 mass, which, when heated, yielded about a fourth of its weight of pure 

 nitrous oxide. There can be no doubt that he had obtained potassium 

 nitrososulphate, but there can be no doubt, also, that he did not know 

 it, did not isolate the salt, and that he thought the product to be 

 potassium hyponitrite, formed from nascent nitrous oxide, the nitric 

 oxide taken having been deoxidised by the sulphite. It was Davy's 

 observation that led Pélouze to investigate what the action really was, 

 and to the discovery of the nitrososulphates ; but that is all that Davy 

 had to do with the discovery. 



