478 Miscellaneous Intelligence. 



it in a purer state, and in greater abundance. Chlorate of potassa 

 is to be placed in a retort, with rather a large neck, and heated 

 until the moisture is dissipated ; then, at the time when oxygen is 

 freely evolved from the salt, iodine is to be introduced by means of 

 a metallic spoon as far as the body of the retort. The vapours of 

 iodine which will be occasioned by the heat will immediately dis- 

 appear, in consequence of their combination with the oxygen of the 

 chlorate, and a strong effervescence will be perceived in the latter^ 

 occasioned by each portion of iodine with which it may combine ; 

 immediately yellow vapours will be perceived in the neck of the 

 retort, and when they redden litmus paper, and a sufficient quan- 

 tity of iodous acid has been obtained, the operation is to be 

 finished, and the acid collected, the last portion being removed by 

 a drop or two of water. 



All attempts to unite this acid with alkaline bases have failed, 

 the iodine being precipitated ; this happens equally with ammonia, 

 potassa, and soda, the attraction between the elements of the acid 

 being so weak as to allow of their complete separation on these 

 occasions. 



Oxide of Iodine was discovered in attempts to combine iodine 

 and oxygen directly together. It is to be obtained in the following 

 manner. A copper tube about two palms (20.6 inches) in length, 

 and eight lines in diameter, having one extremity terminated in a 

 screw, and the other by a small aperture about a line in diameter^ 

 was fixed upon two supports ; the contracted extremity was curved, 

 so as to permit of its introduction into the tubular of a retort, with- 

 out deranging its convenient inclination. A bladder filled with 

 oxygen gas was attached to the screw. A long spirit-lamp with 

 several wicks was placed beneath the lower part of the tube, so as, 

 when necessary, to raise it to redness. Arrangements were also 

 made for applying a lamp to the bottom of the retort, to elevate 

 its temperature, it having been found that to combine oxygen and 

 iodine, both should be at a high heat. 



The tube and the retort being heated to redness, one person 

 then presses the bladder to force heated oxygen into the retort, and 

 another introduces a spoonful of iodine through the neck of the 

 retort until it is brought under the jet of gas. The iodine is 

 quickly converted into violet vapour, which fills the retort, but this 

 soon disappears, and the retort neck becomes lined with a yellow 

 transparent substance, almost solid ; which, by the continuance of 

 the operation, becomes more fluid, and flows forward as an olea- 

 ginous liquid. If the violet vapours are too abundant, the spoon 

 is to be withdrawn for a little while, the introduction of oxygen 

 being continued ; when they have disappeared the iodine is to be 

 re-advanced. 



The substance obtained in the commencenient of this operations 

 is oxide of iodine. It is of the consistence of a solid oil, has an 

 acrid, disgusting taste, an odour similar to that of iodous acid, but 



