DETONATION OF THE OXY-MURIATS. 
451 
which soon exhaufts the strength of the gas. Attempts have also been 
made to bleach rags for paper. The methods employed are frequently 
to wet the matter to be bleached, by dipping it into water, while it is 
at the ſame time exposed to the vapour of the acid; or water which 
has been made to absorb some of the vapour is applied to it; or it 
is steeped in a solution of fixed alkali, or in lime-water, which has ab 
forbed some of the vapour. Such solutions are found to have the 
bleaching power, although the acid be saturated with alkali. 
Different methods are employed by different manufacturers, accord 
ing to their notions of their respective efficacy; and each manufacturer 
has his nostrum, which is a secret. At present, none of them, I believe, 
use the simple oxygenated acid, which was formerly prepared for them, 
as a ſteep. The ſmell which it occaſions is abominable, and cannot be 
cleared from the hands for many days. The workmen therefore will 
not submit to it. They either uſe the vapour procured by Berthollet's 
proceſs, with alternate dippings into water, —the whole of which ope 
ration is performed in a close chamber by the intervention of machi 
nery; or, more commonly, they employ solutions of alkali impregnated 
with the vapour. A chemist in Glaſgow has made a great improve 
ment upon the whole proceſs, by employing lime instead of alkali. 
He thereby prepares the drug in a very concentrated, and even a solid 
state. 
Mr. Berthollet's trials to combine this volatile acid with fixed alkali 
have also produced some other surprising discoveries. Observing how 
much the oxyd itself was dispoſed to give out its oxygen to inflam 
mable substances, and how loosely it is combined in the acid over 
charged with it, while this acid ſtill retains its relation to alkalis, he 
tried the effect of the neutral salts produced by it. When the oxy 
genated muriat of potash is ground in a mortar with sulphur, small 
explosions happen under the pestle, which affect the hand of the opera 
tor like an electric shock; and if hastily ground, with strong pressure, 
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