on the Salts usually called Hyperoxyrmirlates, ^V. 429 



compound, and I hope soon to have the means of making a de- 

 oisive experiment on tni? subject. 



It appears that this uew sul)stance, thorgh it contains four 

 proportions of oxygen, is not an acid ; and hence it is probable, 

 that tlie acid fluid compomid of oxygen, cldorine, and Vv-ater, 

 whicli M, Gay Lussac calls chloric acid, o'.ves its acid powers to 

 combined hydrogen, and that it is analogous to the other hyper- 

 oxvmuriatcs, which arc triple compounds of inflammable bases, 

 chlorine, and oxygen, in which the base and the chlorine deter- 

 mine the character of the compound. Muriate of potassa 

 (potassaae) is a perfectly neutral body; and when six proportions 

 of oxygen are added to it, it still remains neutral. Muriatic 

 acid (chlorine and hydrogen) is a strong acid ; and according to 

 the relation above stated, it ought not to lose its acid powers by 

 the addition of six proportions of oxygen. Till a pure combi- 

 nation of chlorine and oxygen is obtained, possessed of acid pro- 

 perties, we have no right to say that chlorine is capable of 

 being acidified by oxygen, and that an acid compound exists in 

 the hyperoxymuriates. We know that chlorine is capable of 

 being converted into an acid by hydrogen, and, as I mentioned 

 in my last paper, where this princi])le exists its energies ought 

 not to be overlooked; and all the new facts confirm an opinion 

 which I have more than once before submitted to the considera- 

 tioa of fche Society, namely, that acidity does not depend upon 

 any peculiar elementary substance^ but upon ptculiar combina- 

 tions of various substances. 



Rome, Feb. 15, 1815. 



Note. 



Since my return to Englaiul, I liave mndc some further investigations on 

 oxyiodine, on the ox\iof)cs, and on the deep yellow gas. The portable ap- 

 paratus which I employed in Italy, enabled ine to operate only on very 

 minute quantities of oxyiodinc; 1 have lately made my experiments on a 

 larger scale. 



Thir'teen grains of owiodine dccompoised by Iieat, alTurdcd 9 25 cubical 

 inches of oxygen: and 48 grains of oxypotassanie or oxyiode of potassium 

 yielded when decomposed by heat 31 cubical inches of oxygen gas: and 

 30 grains of potassame or iode of potassium (a portion of The salt so de- 

 composed) afforded by treatment with nitric acid IT'S grains of dry nitre. 

 These results give the number 246 as the number representing iodine, and 

 prove that oxyiodine consists of one proportion of iodine and five of oxy- 

 gen ; and that the oxyiodes contain six proportions of oxygen. 



The deep-yellow gas when mixed with chlorine in the proportion of 2 to 

 3, or even of 2 to 2, deprives it of the power of acting upon Dutch fr)il, 

 though one of chlorine when mixed with two of comtnon air still burns 

 this substance. Hence it appears probable, that the deep-coloured gas 

 and chlorine hat'e a chemical action on each other, and tliat euchlorine i» 

 not a Kimple mixture of them. I hope soon to be able to present to the 

 Society some new results on this subject. 



London, June 12, 1815. 



LXXX. New 



