126 On Sir H. Davy's Theory of [Au«. 



to the attractions between the chlorine and the manganese, and 

 between the hydrogen and the oxygen; which, together with 

 the disposition of the chlorine to assume the elastic form, must 

 be conceived sufficient to overcome the attractions between the 

 manganese and the oxygen, and between the chlorine and the 

 hydrogen. To this explanation, however, besides the gratuitous- 

 assumption that chlorine attracts the manganese more strongly 

 than oxygen does, it is absolutely indispensable that hydrogen 

 should attract oxygen more strongly than it attracts chlorine : 

 yet, as is remarked by an anonymous correspondent of Mr. 

 Nicholson,* Sir H. Davy afterwards infers that the attraction 

 between chlorine and hydrogen is the more powerful. t 



2. Of the Action of strong liquid Muriatic Acid on Hyper-oxy- 



muriate of Potash. 



It may be well to take a brief view of the formation of this 

 salt, before proceeding to consider the process for obtaining 

 oxymuriatic gas from it. 



If a stream of oxymuriatic gas be passed through a solution of 

 potash, it undergoes a change ; in consequence of which we find 

 in the liquid the two salts known by the names of muriate and 

 hyper-oxymuriate of potash. According to the old theory, this 

 change consists in the extrication of oxygen from part of the 

 oxymuriatic gas, and the absorption of this oxygen by the 

 remaining portion. On Sir H. Davy's principles, the most 

 direct explanation is, that part of the chlorine decomposes a 

 portion of the water, forming muriatic acid by union with its 

 hydrogen, while the rest of the gas, uniting with the oxygen of 

 this portion of water, gives rise to hyper-oxymuriatic, or, as it 

 would almost require to be called, chloric acid. To this expla- 

 nation it were needless to urge any objection, as Sir H. Davy 

 does not give it his sanction. He holds the salt known by the 

 name of hyper-oxymuriate of potash to be composed of a gas, 

 which he has called euchlorine, united to peroxide of potassium. 

 The merits of this opinion I shall have occasion to discuss in the 

 sequel. 



Another idea has been started witli regard to the nature of this 

 salt by Mr. Crane, % who holds it to be composed of chlorine, 

 water, and the unknown base of the alkali. If, however, water 

 be the source of all the oxygen which may be procured by heat 

 from the salt in question, that compound must exist in it in the 

 proportion of at least 44'SS3 grs. to 100 grs. 3 and the hydrogen 



* Nicholson's Jouftial, vol. xxviii. p. 360. 



+ Phil. Trans 1911, p. 158. Sec also p. 29 of the same vol. where these 

 opposite modifications of affinity are successively reasoned on in two successive 

 paragraphs. 



i Nicholson's Journal, vol. xxix. p. 44$ &c. 



