12 Taylor, Hypoiodous Acid and Hypoiodites. 



occasion, that when boiled for one hour, 52 per cent, 

 of the bleaching power had disappeared. In another 

 experiment a sample was boiled for seven hours, and 

 then only lost 53 per cent, of its bleaching power ! 



It is evident that there are some irreconcileable dis- 

 crepancies between these results and mine. In the first 

 place, I never found any difficulty in estimating the 

 bleaching power of a solution directly, except in the case 

 where the bleaching is not permanent. Secondly, my 

 solutions gave black precipitates with cobalt ; and, in the 

 next place, every bleaching solution that I have made is 

 decomposed completely by boiling for, at most, four 

 minutes. Judging from the analogous bodies, hypo- 

 chlorites and hypobromites, and from the instability of 

 riyopiodites on merely keeping them in the dark, it is 

 inherently highly improbable that any hypoiodite could 

 stand being boiled for seven hours ! I have prepared 

 what I should call calcium hypoiodite by adding lime- 

 water to aqueous iodine, and it decomposes completely 

 when boiled for three minutes. Whether the complicated 

 method adopted by Lunge and Schoch for estimating the 

 bleaching action has anything to do with these dis- 

 crepancies I am not prepared to say, but it seems quite 

 plain that if Schonbein's solutions consist of hypoiodites, 

 then Lunge and Schoch's solution does not. I have tried 

 to repeat Lunge and Schoch's experiments, following their 

 directions, and have obtained a bleaching liquid which 

 acts practically like Schonbein's solutions ; that is, there 

 is little or no difficulty in estimating the bleaching power 

 directly, and it loses its bleaching power completely when 

 boiled for a few minutes. If, also, as I should recommend, 

 the iodine and lime are rubbed together with water, and 

 then diluted immediately, instead of, as they recommend, 

 allowing the mixture to stand for several hours, a solution 

 is obtained three or four times as strong, which gives a 



