346 Expmments on a solid Compound 



ordinary temperature of the atmosphere. As soon as the eu- 

 chlorine conies in contact with the iodine, there is an immediate 

 action, its colour changes to bright orange, and a liquid is 

 formed. VVlien the euchlorine is in sufficient quantity, a white 

 substance likewise appears. By the application of a gentle heat, 

 the orange compound of chlorine and iodine may be made to 

 rise in vapour : and the compound of oxygen and iodine re- 

 mains. 



When this compound is required to be dry, the euchlorine 

 should be passed through dry muriate of lime (calcane) before 

 it is admitted to the iodine. The apparatus that I have em- 

 ployed for producing the substance is a curved bent tube, in the 

 form of an inverted L (q), closed at one end, the closed leg of 

 the tube being fongest, and which serves as a retort for genera- 

 ting the gas f a thin long-necked glass receiver for containing 

 the iodine, and a curved tube of smaller diameter than the first, 

 and cemented or ground into it for conveying the gas into the 

 receiver. The muriate of lime is placed in some dry paper in 

 the upper part of the large curved tube ; and to produce the 

 substance from 40 grains of iodine, 100 gi'ains of the hyperoxy- 

 muriate should be used, and four times the quantity of solution 

 of muriatic acid of specific gravity about 1*005; a very small 

 spirit lamp should be employed to generate the gas ; and to 

 prevent explosions, the heat should be applied with great care, 

 and only to the bottom of the tube. 



The compound of oxygen and iodine when entirely freed by 

 heat from the compound of oxygen and chlorine, appears as a 

 white semi-transparent solid; it has no smell, but a strong 

 astringent sour taste. Its specific gravity is considerable, for it 

 rapidly sinks in sulphuric acid. When heated strongly, it de- 

 composes, undergoing fusion at the moment, and is entirely 

 converted into gaseous matter and iodine, leaving no residuum 

 whatever. 



It requires for its entire decomposition a heat which is rather 

 below the boiling point of oHve oil, and there seems to be little 

 or no increase of temperature in the process. 



Its nature is proved both by analysis and synthesis ; for when 

 euchlorine acts upon iodine, the volatile substance produced has 

 all the characters of the body produced by the immediate action 

 of chlorine on iodine; and when the compound I am describing 

 is decomposed in a pneumatic apparatus, the gas formed is found 

 to be pure oxygen, and the solid sublimate produced is pure 

 iodine. 



I endeavoured to determine the proportions of the elements 

 in the compound, by decomposing it in glass tubes carefully 

 weighed, and ascertaining the loss of weight of the tube, and 



the 



