, acts on gold merely
in virtue of the oxy-muriatic acid which it contains.

Sulphur, volatile oils, and many other substances, will burn in the same
manner in oxy-muriatic acid gas; but I have not prepared a sufficient
quantity of it, to show you the combustion of all these bodies.

CAROLINE.

There are several jars of the gas yet remaining.

MRS. B.

We must reserve these for future experiments. The oxy-muriatic acid does
not, like other acids, redden the blue vegetable colours; but it totally
destroys any colour, and turns all vegetables perfectly white. Let us
collect some vegetable substances to put into this glass, which is full
of gas.

EMILY.

Here is a sprig of myrtle--

CAROLINE.

And here some coloured paper--

MRS. B.

We shall also put in this piece of scarlet riband, and a rose--

EMILY.

Their colours begin to fade immediately! But how does the gas produce
this effect?

MRS. B.

The oxygen combines with the colouring matter of these substances, and
destroys it; that is to say, destroys the property which these colours
had of reflecting only one kind of rays, and renders them capable of
reflecting them all, which, you know, will make them appear white. Old
prints may be cleaned by this acid, for the paper will be whitened
without injury to the impression, as printer's ink is made of materials
(oil and lamp black) which are not acted upon by acids.

This property of the oxy-muriatic acid has lately been employed in
manufactures in a variety of bleaching processes; but for these purposes
the gas must be dissolved in water, as the acid is thus rendered much
milder and less powerful in its effects; for, in a gaseous state, it
would destroy the texture, as well as the colour of the substance
submitted to its action.

CAROLINE.

Look at the things which we put into the gas; they have now entirely
lost their colour!

MRS. B.

The effect of the acid is almost completed; and, if we were to examine
the quantity that remains, we should find it to consist chiefly of
muriatic acid.

The oxy-muriatic acid has been used to purify the air in fever hospitals
and prisons, as it burns and destroys putrid effluvia of every kind. The
infection of the small-pox is likewise destroyed by this gas, and matter
that has been submitted to its influence will no longer generate that
disorder.

CAROLINE.

Indeed, I think the remedy must be nearly as bad as the disease; the
oxy-muriatic acid has such a