the oxygenated muriatic Acid. 303 
sible, when the truth may be established by experi- 
ment; and as I thought the matter of sufficient im- 
portance, I made the following experiments on the 
subject. 
I beg leave to premise, that in all these experi- 
ments, I made use of one and the same acid, which 
was kept ina bottle with a ground-glass stopper, 
and secured from the influence of light. The 
manner in which I made the experiments was sim- 
ply this. I weighed, first of all, a bottle filled with 
the colouring substance which I meant to employ : 
I then weighed, in a large and perfectly colourless 
bottle, half an ounce of the acid, to which I imme- 
diately, but very gradually, added of the colouring 
substance contained in the former bottle, till the 
acid ceased to destroy any more of its colour. The 
bottle with the colouring substance was then weigh- 
ed again, and the difference between its present and 
original weight was noted. ‘The same method was 
observed in all the experiments. 
'-EXPERIMENT I. 
To half an ounce of oxygenated muriatic acid, I 
added a solution of indigo in acetous acid,* drop by 
’ * It has been usual to estimate the strength of the oxy-: 
genated muriatic acid by a solution of indigo in sulphuric 
acid. This method was inadmissible in these experiments _ 
on the comparative strength of the bleaching liquor, with 
and without alkali; because the sulphuric acid would have 
decomposed the muriat of potash, and thercby produced 
