3$f2 Prepcration and HaiUtiiei of the Oxygenated Muriat of Potafj, 



alkali was employed. A given quantity of the ftrong folution of potafh appeared to pro- 

 duce more of this fait than the fame quan;;ity of a folution of pearlalh of the fame fpecific 

 gravity. - 



The remaining lixivium, on evaporation, did not yield this fait, though a muriat of 

 potafh was formed, that appeared to be confiderably oxygenated : fince, with the addition 

 of the fulphuric or muriatic acid, it became a very powerful deftroyer of vegetable colours ; 

 it would not detonate with fulphur, or inflame combullible fubltances, with acids ; it was 

 very foluble in water, much more fo than tlie muriat firft formed fiom the fame alkali. 



I may here remark, that I think the French chemifls were fight in calling the firft fait 

 the hyperoxygenated muriat, as the fait laft mentioned is certainly oxygenated in fome de- 

 gree : however, in the following experiments I fliali ufe the term oxygenated muriat, when 

 fpeaking of the fait formed during the diftiilation, and on cooling the lixivium after being 

 faturated with the gas. 



Experimetit I. One part of the oxygenated muriat of potafh required about feventeen 

 parts of water at the temperature of 60°, to diflblve it ; whilft five parts of boiling water ■ 

 diffolved two of the fait. Repeated folutions did not appear to injure, but rather to increafe, 

 its detonating property. The cryftals became much whiter ; and a quantity of the earthy 

 matter before mentioned was feparated at every frefh cryftallization. 



Experime?it 11. A quantity of this fait was put into a bottle, and placed in a fituation 

 aiuch expofed to the light : after being kept there more than twelve months, it die! not ap- 

 pear to have loft any part of its detonating property. This fa£t is contrary to Chaptal's 

 aflcrtion, that the mere imprefllon of light is fufEcient to decompofe it *. 



Experiment III. Water faturated with this fait was expofed to the light for feveral 

 months, without appearing to be at all changed. It was put into a bottle with a ground 

 Hopper and tube, to which an apparatus was adapted to receive any gas that might come 

 over ; but no gas whatever was difengaged. 



Experiment IV. Sixty grains of fait w,ere fufed by the heat of a lamp in a bottle with a 

 ground ftopper and lube. After having been kept in a fluid flate for about half an hour, I 

 found that it had loft two grains in weight, and that a fmall quantity of air was given out,, 

 which proved to be oxygenous by the teft of nitrous gas. The fait which had been melted 

 would ftill detonate with fulphur, &c. The lofs of weight was, I am inclined to think,, 

 chiefly owing to the efcape of the water of cryftallization ; for the fait when cool had loft, 

 its tranfparency. 



Experiment V. From forty grains of the fait in an earthen retort, I procured by the ap- 

 plication of heat about thirty-fix cubic inches of oxygenous gas ; the evolution of which. 

 was very rapid, and commenced as foon as the retort became flightly red. Forty grains 

 expofed in a crucible to a ftrong red heat appeared, from the mean of. two experiments, to 

 have loft about feventeen grains in weight. The remaining muriat, being afterwards 

 thrown into the fulphuric acid, produced a very ftrong fmeil of oxygenated muriatic acid j 

 from which I inferred chat the whole of the oxygen hjd not been expelled by the heat j. 

 'ji hence the oxygenated muriat of potafli may, 1 liiink, be ftatcd to contain about half its 

 ufeight of o;£ygcu in a concrete ftate. 



• Elements of Chcmiflry, i, a 50. 



Experiment- 



