148 Correspondence of 



suh-eiunrVme, or iodine simply oxygenated, the euiodine being 

 considered as hyperoxygcnnted. The combinations which this 

 body contracts with the acids are analogous to tho'-e which it 

 contracts with water. It is probable that the light will se- 

 p.irate the oxygen horn it, as well froni the sulveniodine as from 

 tile iodine, and will leave the two acids as it were with analogous 

 engagements to the fluorico-boric, carbonico-muriatic gases, 

 &:c. These compounds are yery curious. What has been 

 hitherto regarded as insulated tui.hlorine, is in the same way 

 only oxygenated chlorine, the euchlorine being hvperoxygenated 

 chlorine. The dry acid in this compound is at all times free 

 enough, by its subsolution by the acid of the oxygen, to unite 

 with the oxiduiate of mercury, without adding to its degree of 

 oxidation. 



I am informed that Sir Humphry Davy has undertaken a la- 

 borious incpiirv into the de-hydrogenation of the fluoric acid into 

 fluorine, availing himself of iodine with this view. I shall ven- 

 ture to predict that his researches will be fruitless. I have made 

 many experiments with the same view, but I never perceived the 

 slightest prospect of succeeding. The fluoric acid is not oxy- 

 genable into fliiorine, and it is not jjcrhaps any more hydrogen- 

 able into fiiior ; but it will rather be the latter than the former, 

 since already it ))refers the most feeble reduced metals to those 

 most strongly oxidated. Gold, platina, &c. separate it from 

 lime: it is upon those compounds of dry fluoric acid and upon 

 reduced metals, or upon the metallo-flnors, that all attempts 

 must be made to deiiydrogenate this acid. But according to my 

 first results, there are formed /?t^//?ei' very much hypercomposed 

 of metal, and from which the fluor does not appear separable. 

 We nmst find out a metal not susceptible of Jli/urisalinn, and 

 it would be fortumite if we could find it among the volatile me- 

 tals, at least if the fluor be not volatile, and then act on the 

 mctailo fluor of this metal, made red hot by means of a stream 

 of hydroi^cn gas. It is singular that the hydrargyro-fluor is not, 

 any more than the two hydrargyro- mures, or hydrargvro-chlores, 

 volatile in the fire. If there existed a metal nearly inoxidable, 

 we might expect that its fiuoiic would be given up to the oxy- 

 gen, the metal remaining untouched, and then the fluorine will 

 be produced. With the fiuors of ordinary metals, the metal is 

 oxidated, and dry fluatc results from its combination with the 

 Jliioric. I call fluoric the dry fluoric acid, or fluoric acid gas 

 without any water; Jluorine when it is freed from oxygen; and 

 ^Tio/f when freed from hydrogen; and dry Jiuales when freed 

 from their oxides. This dry acid has no insulated existence, any 

 moie than the muriatic, iodic, sulphuric, azotic, &c. It is a 



body 



