An EJfay on Bleaching, 249 



Tn whatever manner the oxygenated muriatic acid is pro- 

 cured, it is evident that the oxygen adheres to it only weakly; 

 an! U is on this property that The pofribility depends of pro- 

 ducing fp'eedily in manufactories that action which the 

 atmoipbere produces but (lowly, and of bleaching in a fpace 

 of time proportionally fhort. 



Oxygenated muriatic acid is produced by diftilling together 

 fulphu.-ic acid, manganefe, and muriate of foda, (common 

 fait,) and condenfing in water the acid gas which thence 

 efrapes. The apparatus and proportions of the ingredient* 

 Will be treated of when we come to fpeak of the procefTes tor 

 bleaching with this acid. 



Oxygenated Muriates, 



Notwithstanding the little affinity which fome earths and 

 alkalies have for the oxygenated muriatic acid, means are found 

 to combine them together, and to compofe fubftances called 

 oxygenated muriates. Of the earths, none but lime and mag- 

 nolia can be conveniently converted into oxy-muriates; and 

 the latter is even too dear to be employed. The oxy-muriate of 

 lime isatprefent ufed at all the bleaching-grounds of Ireland. 

 For the procefs cf preparing it we are indebted to Tennant: 

 he combines it with the oxygenated muriatic acid under the 

 gafeous or liquid form; but the latter is preferable. Lime 

 water faturated with oxygenated muriatic acid may be em- 

 ployed liquid ; or, by fuperfaturating the mixture, the earthy 

 moleculae may be precipitated to the bottom of the appara- 

 tus : if the liquor, whieh is always fureharged with oxygen- 

 ated muriatic acid, be then drawn off by means of a fyphon, 

 you will obtain a refiduum faturated with that principle, the 

 palte of which may be employed in the procefTes of bleaching. 

 This oxy-muriate, under the concrete form, is fufHcientlv 

 impregnated to form a bleaching ley when diflblved iii water. 



The 'alkalies of which fuch oxy-muriates may be formed 

 are barytes, potafh, and ftrontian. The firft and the laft are 

 -{till too rare, and their price is too high, to l'uit that ceco- 

 nomy which the procefTes for bleaching require ; but thefe 

 fubftances have begun to be discovered in France. In regard 

 to potalh, we are already acquainted with the part it acts \i\ 

 condeniing the oxygenated muriatic acid, and rendering it 

 inodorous. To obtain the fame remits with oxy-muriate of 

 lime, nothing is neceflary but to laturate it in like manner. 



The advantages obtained by thefe preparations are very 

 important. 



One is enabled to make thefe leys, and to fend to a diftancc 



thefe-nuiriatesj -which form the deterfive fubllance, without 



Vjfo > fear 



