THE BLEACHING COMPOUNDS OF CIILORIXK. 309 



come oxichlorides, giving rise to a slight disengagement of chlorine 

 mixed with oxygen. Mercuiy is changed into red oxichloride by con- 

 tact with hypochlorite of lime. 



The recently precipitated sulphurets are immediately converted into 

 sulphates by the hypochlorites ; and these salts, as well as the hypochlo- 

 rous acid, might undoubtedly, as well as oxigenated water, serve for the 

 restoration of pictures, in which the white colour employed in painting 

 has become black by the change of carbonate of lead into sulphuret. 



The greater part of the combinations of oxygen which are not satu- 

 rated M'ith this principle, undergo the same action by the hypochlorites 

 as by hypochlorous acid itself. Thus nitric oxide is absorbed by them 

 as by the decolorizing chlorides, and converted into nitric acid. The 

 metallic protoxides are converted into peroxides, and the salts in ite are 

 con^•erted into salts in ate. It is not necessary to enumerate in detail 

 all these re-actions, which are absolutely the same, as chemists have 

 already observed, with the decolorizing chlorides. 



The comparative action of the hypochlorites and decolorizing chlo- 

 rides upon some organic matters proves, as well as the preceding facts, 

 that a perfect identity exists between these bodies. Both possess the 

 same power of destroying vegetable colours ; but for this purpose they 

 must not have excess of base ; for alkaline hypochlorite of lime and 

 tincture of litmus may remain during some hours in contact without 

 the colour being destroyed. 



It is well known with Avhat activity concentrated decolorizing chlo- 

 rides attack fabrics. The pure hypochlorites, unmixed with chlorides, 

 possess also this property in a high degree : their action upon lignin, 

 and especially upon filtering-paper, is attended with a considerable dis- 

 engagement of heat ; and as the hypochlorites are susceptible, as I have 

 already stated, of being converted by heat into chlorides and chlorates 

 with the disengagement of oxygen, the heat developed effects this con- 

 version and produces this disengagement. The paper is essentially 

 altered ; it usually becomes friable, but it is not carbonized ; and when 

 .the operation is conducted in a close vessel, so as to collect the gases, 

 it is found that little but oxygen is disengaged, mixed with a small 

 quantity of carbonic acid. But if rather a large quantity be acted 

 upon, the heat developed is more intense ; the paper then inflames, and 

 there is a production in this case, not of oxygen, but of carbonic acid. 



The experiments of M. Soubeiran and of M. Liebig have proved that 

 the decolorizing chlorides can convert alcohol into a peculiar chloride 

 of carbon. I readily convinced myself that the hypochlorites possess 

 the same property. I have not analysed the compound of chlorine and 

 carbon which is produced in this case ; but its physical properties, and 

 especially its odour, so much resemble those of the chloride of carbon 

 examined by M. Liebig, that I ha^e no doubt of their being identical. 



Vol. I — Part II. v 



