Intelligence and Miscellaneous Articles. 1 49 



ON PUIIE IOD1C ACID AND THE DETECTION OF THE VEGETABLE 



ALKALIES. 



M. Serullas has found 



1st, That when perchloride of iodine is mixed with water, there 

 results iodic and muriatic acid from the decomposition of the water. 



2nd, That the solid perchloride of iodine, previously slightly 

 washed with water, or still better with a solution of the perchloride, 

 when mixed with aether or concentrated alcohol, is suddenly con. 

 verted, by the elements of water, into muriatic acid, which remains 

 in solution, and very pure iodic acid, which is precipitated, on ac- 

 count of its insolubility in alcohol. 



3rd, That oxide of silver, agitated in proper quantity in a solution 

 of perchloride of iodine, seizes only the muriatic acid, leaving free 

 and pure iodic acid in solution. 



4th, That iodic acid (and the solution of perchloride of iodine, 

 on account of the iodic acid which it contains, produces the same 

 effect) combines rapidly with the vegetable alkalies, forming very 

 acid compounds with these bases, which are almost insoluble in 

 concentrated alkohol ; this aftbrds a method of discovering very 

 small quantities of these alkalies in solution in alcohol, which is a con- 

 dition in which it is easy to place them. Ann.de Chim., Sept.1830. 



PAHA-TARTARIC ACTD. 



M. Dulong communicated to the Academy of Sciences a letter 

 from M. Berzelius, relating to several chemical compounds, which 

 are perfectly similar to each other in the nature and proportion of 

 the elements of which they are composed j but are very different in 

 their physical and chemical properties. M. Berzelius has paid par- 

 ticular attention to the new acid which M. Gay-Lussac has met 

 with in tartar, and which has been called Thannic acid; M. Berzelius 

 shows that this acid, which possesses very different properties from 

 tartaric acid, gives by analysis a perfectly similar composition. It is 

 also well known that common phosphoric acid, and that which has 

 been recently calcined, and which has been called pyrophosphoric 

 acid, offer very considerable differences in their properties ; it is also 

 the same with stannic acid (deutoxide of tin), accordingly as it is 

 prepared by treating tin with nitric acid, or by decomposing the 

 deutochloride, or fuming liquor of Libavius. 



M. Berzelius, in order to connect all these observations, proposes 

 to call those bodies isomeres (of equal elements) which possess the 

 same composition, and to add the Greek preposition para to that of 

 the two bodies which occurs most rarely, and is obtained with most 

 difficulty ; thus common phosphoric acid will be termed simply 

 phosphoric acid, and the pyro-phosphoric will be termed para- phos- 

 phoric, and we shall have also tartaric acid and para-tartaric acid, 

 stannic acid and para-stannic acid. Jbwrw. de Pharm, Oct. 1830. 



ON THE CHLORIDES OF IODINE AND THE DETECTION OF THE 

 VEGETABLE ALKALIES. 



M. Serullas lately read a memoir on the above compounds before 



the 



