Intelligence and Miscellaneous Articles. 85 



ACTION OF IODINE ON CERTAIN SALTS. BY M. FILHOL. 



Several years since M. Berthemot produced, for the first time, a 

 compound of iodine and lead possessing a fine blue colour ; it was 

 mentioned rather later by M. Denot, and it has been more recently 

 examined by M. Durand. 



In order to determine its chemical composition, M. Filhol first 

 examined that of the solutions which are used in forming it ; this 

 included the action exerted by iodine on carbonates ; the results 

 showed that iodine acting in the cold upon the alkaline carbonates, 

 forms bicarbonate of the base, an iodide and iodate. 



By the action of a solution of bi-iodide of potassium upon a solu- 

 tion of acetate of lead, a violet-red coloured precipitate was formed, 

 which was very unstable ; when heated to 230° F. it loses 9.Q-&Q 

 per cent., or 1 equivalent of iodine, and leaves a residue of PPb. 

 -j-PbO. If care be taken not to heat the compound to above 230°, 

 the residue is of a fine green colour ; but if the temperature be raised 

 to 266° or 284°, the green colour is lost, and it becomes of a pale 

 yellow without losing a trace of iodine. The composition of the 

 red powder is such, that it may be considered as formed of bi-iodide 

 of lead combined with oxide of lead (2P + Pb) + PbO, or as formed 

 of I-Pb + JsPbO. 



When treated with excess of acetic acid this powder is decom- 

 posed ; iodine separates, some oxide of lead combines with the acetic 

 acid, and the residue is a new oxi-iodide of lead composed of 2P 

 -1-PbO. 



M. Filhol states that this red powder is one of the constituents 

 of the blue compound, and that it may be produced by mixing the 

 red powder while moist with nascent carbonate of lead ; or, which is 

 better, by employing a solution which produces both at the same 

 time ; the blue powder constitutes a compound of a new class, and 

 the author proposes for it the name of iodo-carbonate of lead : it is 

 obtained of a very fine colour by precipitating a solution of acetate 

 of lead, with one formed of 1 proportion of bi-iodide of potassium 

 and 4 of carbonate of potash. 



The analysis of the blue compound gave the following as its for- 

 mula : r-Pb + PPbO+4(C02PbO). 



[The atomic weight of iodine in the above notice is, we believe, 

 only half of that assigned to it in England. — Edit.] 



Jonrn. dePharm. ct de Ch., Decerabre 1844. 



ON A NEW COMPOUND OF SULPHUR, CHLORINE AND OXYGEN. 



M. Millon, in attempting several years ago to combine a larger 

 proportion of chlorine with sulphur than had been previously done, 

 remarked the formation of a crystalline compound which he supposed 

 to consist entirely of sulphur and chlorine. But on reproducing this 

 substance repeatedly, the author found that it was obtained in pro- 

 portion to the excess of chlorine and the smallness of the moisture 

 which it contained. 



From the period of this discovery, he suspected the presence of 

 oxygen : by adopting a peculiar mode of preparation the product 



