M. Serullas, 07i Hydriodide of Carbon. 299 



M. Serullas conceives that, without the concurrence of potash, 

 the simple act of dissolving chloride of iodine in alcohol is 

 not sufficient to decompose the water, and produce hydnodide 

 of carbon ; for the existence of this hydriodide is not mamtested 

 till during the saturation, beginning, probably, at the moment 

 when the iodine of the sub-chloride is set at liberty, and it is 

 onlv when the saturation is completed, that the liquor acquires 

 the Yellow colour, the saccharine taste, and the peculiar odour, 

 which distinguish the hydriodide. Saturation by pure mag- 

 nesia produces no hydriodide. This compound is solid, ot a 

 lemon-colour, and a saccharine taste, which becomes very mani- 

 fest when it is dissolved in alcohol. It crystallizes m spangles of 

 a brilliant aspect. Its smell is aromatic, approaching nearly 

 to that of saffron. Its specific gravity is nearly double that 

 of water. It is not sensibly soluble in this liquid. It dissolves 

 in 80 times its weight of alcohol of 0.825 sp. grav., at the 

 ordmary temperature; and in 25 times, at a temperature of 

 95° Fahr Seven parts of ether dissolve one of hydriodide. 



Fat and volatile oils dissolve It readily. In the latter at 

 least in the essence of lemons, it suffers an alteration; for, 

 on exposure to light, charcoal is evolved, and the iodine be- 

 comes free. Sulphuric, sulphurous, nitric, and muriatic acids 

 have no action upon it; nor has a solution of chlorine m 



Exposed to the air, at common temperatures, it disappears 

 at thTend of a certain period. Aheat of 212° Fahr volatilizes 

 h without decomposition; between 240° and 248° it enters 

 into fusion, and is soon afterwards decomposed, giving rise to 

 vapours of iodine, a deposit of very brilliant charcoal, and 

 hvdriodic acid. A portion is volatilized at the same time Ot 

 all the simple non-metallic bodies, chlorine in the state of gas, 

 is the only one which presents, with hydriodide of carbon, very 

 remarkable phenomena. , 



These two bodies scarcely come into contact before there 

 is a lively action, and sudden decomposition of the hydriodide ; 

 whence products result, whose nature varies accordmg to 



'"'T'lflhediiorine, as well as the hydriodide, are perfectly dry, 

 there is formed a chloride of iodine, some muriatic acid, and a 

 peculiar white matter containing much carbon. 

 ^ 2 If the chlorine be in excess, there is a formation of a 

 solid yellow chloride ; and one of a subchlonde in the opposite 



case. 



3 ■ When the quantity of chlorine which has been made to 

 act upon the hydnodide has been sufficient merely to produce 

 asulShloride, there is no longer found in its watery solution 

 the above white matter, but small quantities of a liquid of an 

 oily appearatvcc, which seems to grease the sides of the vessels, 



