S04 
SELECTED ARTICLES. 
to neutralize the chlorine, the chloride may be decomposed as 
fast as it is produced, owing to the insolubility of the oxcihlo- 
ride which will be precipitated, while hypochlorous acid re- 
taining a small quantity of oxide of mercury, or rather mixed 
with a little undecomposed chloride of oxide, will remain in 
solution. Hence it is evident that a solution of this chloride, 
sufficiently strong to undergo spontaneous decomposition, 
should furnish an acid much more concentrated than can be 
obtained from the chlorides of potassa and soda which are not 
susceptible of a similar decomposition. 
The bleaching chlorides of the oxides of zinc and cop- 
per, prepared by saturating chlorine with the hydrated ox- 
ides of these metals, suspended in water, as indicated by Grou- 
velle, give by distillation the same products as the chloride of 
oxide of mercury, which renders it probable that the reaction 
in all these cases is the same. 
Owing to the great solubility of the chlorides of the oxides 
of zinc and mercury, the salts of these oxides are not precipi- 
tated by the neutral chlorides of the oxides of the first section, 
as are the other metallic salts of the last four sections; hence 
an excellent way of ascertaining whether a solution of potassa 
or soda is saturated with chlorine, is to try if it is precipitated 
by a solution of corrosive sublimate. 
Balard considers the bleaching and oxidizing powers pos- 
sessed in common by the hypochlorites and chlorides of ox- 
ides as a strong proof of their identity. They both convert 
the recently precipitated sulphurets into sulphates, and may 
be substituted for peroxide of hydrogen in restoring the co- 
lours of paintings; but the chlorites produce the same effects, 
and yet they cannot be confounded with the chlorides of ox- 
ides. 
The action of nitrate of silver on the chlorides of oxides, 
has been adduced in support of Berzelius' theory of their com- 
position; on mixing the two solutions, chloride of silver is 
precipitated, and the liquid above it bleaches powerfully for a 
few moments; it soon, however, becomes troubled, owing to 
