ch these facts furnish of the acetous acid
being produced by the oxygenation of wine, an experiment made by Mr
Chaptal, Professor of Chemistry at Montpellier, gives us a distinct view
of what takes place in this process. He impregnated water with about its
own bulk of carbonic acid from fermenting beer, and placed this water in
a cellar in vessels communicating with the air, and in a short time the
whole was converted into acetous acid. The carbonic acid gas procured
from beer vats in fermentation is not perfectly pure, but contains a
small quantity of alkohol in solution, wherefore water impregnated with
it contains all the materials necessary for forming the acetous acid.
The alkohol furnishes hydrogen and one portion of charcoal, the carbonic
acid furnishes oxygen and the rest of the charcoal, and the air of the
atmosphere furnishes the rest of the oxygen necessary for changing the
mixture into acetous acid. From this observation it follows, that
nothing but hydrogen is wanting to convert carbonic acid into acetous
acid; or more generally, that, by means of hydrogen, and according to
the degree of oxygenation, carbonic acid may be changed into all the
vegetable acids; and, on the contrary, that, by depriving any of the
vegetable acids of their hydrogen, they may be converted into carbonic
acid.

Although the principal facts relating to the acetous acid are well
known, yet numerical exactitude is still wanting, till furnished by more
exact experiments than any hitherto performed; wherefore I shall not
enlarge any farther upon the subject. It is sufficiently shown by what
has been said, that the constitution of all the vegetable acids and
oxyds is exactly conformable to the formation of vinegar; but farther
experiments are necessary to teach us the proportion of the constituent
elements in all these acids and oxyds. We may easily perceive, however,
that this part of chemistry, like all the rest of its divisions, makes
rapid progress towards perfection, and that it is already rendered
greatly more simple than was formerly believed.

FOOTNOTES:

[29] The word Wine, in this chapter, is used to signify the liquor
produced by the vinous fermentation, whatever vegetable substance may
have been used for obtaining it.--E.

CHAP. XVI.

_Of the Formation of Neutral Salts, and of their different Bases._

We have just seen that all the oxyds and acids from the animal and
vegetable kingdoms are formed by means of a s