392 Intelligence and Miscellaneous Articles. 



concentrated and diluted, and his success has surpassed his expecta- 

 tions. It has, he alleges, effected a speedy cure in cases of caries, of 

 cancer, and of carcinomatous ulcers. 



M. Schweigger-Seidel has made a comparative examination of kre- 

 osote, and the aqua Binelli, from which he has come to the conclusion, 

 that the fundamental base of this hemostatic liquor is kreosote, of 

 which it is only an excessively weak solution. — Edin. Med. and Surg. 

 Journ. 



ON IODOUS ACID. — BY SIG. L. SEMENTINI. 



In a Letter addressed to E. Dakiell, Esq., Secretary of the Royal 



Institution. 



Naples, 20th April, 1833. 

 Sir, — After a long silence, occasioned by ill health, I beg to trouble 

 you with a few scientific observations, which I will thank you not only 

 to make public, but to favour me also with the opinion of the Royal 

 Institution upon their value. 



The many difficulties which I experienced whenever I endeavoured 

 to obtain directly the iodous acid, have induced me to change my 

 method, and I have undertaken another series of experiments and 

 reasonings, of which the following is the result. 



Considering that nitrous acid is nothing else than nitric acid plus 

 nitrous gas, it struck me, by analogy, that an acid, which might pro- 

 perly be called iodous acid, would be the result of a combination of 

 iodic acid with the oxide of iodine, which I had already discovered. 

 Having effected this combination, I obtained from it a liquid of an 

 amber yellow colour, which, when preserved in close vessels, continues 

 to retain the same colour; but which, when in contact with atmo- 

 spherical air, gradually loses its colour, the oxide of iodine being dis- 

 sipated in the same way as when nitrous acid, in contact with air, is 

 discoloured by the volatilizing of the oxide of nitrogen. This com- 

 bination does not take effect in all proportions, but in definite quan- 

 tities, because, if an excess of oxide of iodine be added, this is decom- 

 posed, and the iodine is precipitated. 



This phenomenon can only, I think, be explained by admitting, 

 that when the dose of oxide of iodine is of sufficient strength, the 

 iodous acid, which is immediately formed, decomposes such oxide, 

 depriving it of its oxygen, and is itself again converted into iodic acid ; 

 and, in truth, during the precipitation of the iodine, the liquid is dis- 

 coloured, again losing its yellow colour. This fact appears to me to be a 

 strong proof of the intimate union which takes place between the two 

 compound substances, — each of them evidently acting energetically 

 upon the other. 



This acid, which I call iodous acid, has been made by me by com- 

 bining about one hundred parts of solid iodic acid dissolved in water, 

 with three parts of oxide of iodine, of the greatest density. 



Although the analogy between nitrous acid and iodous acid would 

 imply that this last would not form iodites, as the nitrous acid only 

 forms nitrates, and not nitrites, I combined it with highly saturated 

 ammonia : the union took place without the disengagement and pre- 



