Year: 1872

CDeHnlSlTl vi u DFop vi NlHcsdT.


To the popular mind there are many
"ways that are dark" in the ordinary
operations of nature, and very deep
mystery hangs over the changes and move
ments which occur spontaneously in some
of the most common substances. The fact
that sweet substances like sugar and mo-
lasses are capable of changing into sour
vinegar, IN a few weeks, without any
special human Interference, is perhaps as
great mystery as any which is forced
upon the attention. Whilst it is observed
that there are many solids and liquids in
common use, of sweet or agreeable taste,
which rapidly become sour, it is also no.
ticed that no sour substances ever become
sweet, uuless it may be in the case of the
Juices of some fruit which change during
the process OF ripeniug. Vinegar once
formed from sugar never goes back again
to the saccharine state ;all further changes
are downward toward the inorganic con-
dition. If we add sugar to the liquid, it
does not impart to it taste ofpuro sweet
ness, and it remains distinct body, hav-
ing nc ofinites for the acid with which it
is incorporated. 1t is not surprising that
sugar should be pleasing to the sense of
taste, and be regarded as luxury among
all nations but that vinegar, having pre-
cisely the opposite influence upou the
gastatory nerves, should be freely used
i'll connection with food substances, and
held to be an almost indispensable condi-
meDt, is a matter not a little perplexiug.
1t is clear that the appetite for acid sub
stances is a natural one, and thar vinegar,
like sugar, is capable not only of gratify-
ing the sense of taste. but of meeting cer-
tain wants or conditions Of the system
which are essential to health.


!


The use Of vinegar among the ancients
was very common, and its antiquity is SO
great that it is impossible to learn when
it was first employed. From the writings
of NJ oses we know that the Israeites
used it freely, and among the Eastern ma
tions vinegar, as a condiment and cos.
metic, was highly esteemed. In the entire
absence of chemical knowledge, the fcrma-
ton of the acid from saccharine liquids
must have greatly puzzled the old philoso-
pliers of Greece and Rome, and we have
no doubt they often shook their wise
heads, and stroked their boards, as they
watched with intense interest the fermen-
tative changes which resulted in the pro-
ducticn of the acid. We must not, how
ever. boast extravagantly Of our modern
chemical science, since there are some
points in the wonderful process Of acetous
fermentation which arc not yet quite sat
isfactorily cleared up. But the practical
details and chemical changes that are con.
nected with the formation of acetic acid
are well understood. with the exception
of its production when wood is subjected
to distilation, and this series of reactions
have had much light thrown upon them
by recent investigations.


! Vinegar must be regarded as the most
interesting of all the organic acids not ex.
cepting the malic. Its industrial uses are
very numerous, as under the proper name
of acetic acid it is employed to form many
compounds Of the highest Importance in
the arts. 1t exists ready formed in the
sap Of nearly all plants, and probably in
some of the liquids dependent on the ami
NAL economy, but the quantity is very
small. In the artificial production Of
vinegar it is necessary that alcohol anoth.
er very remarkable organic product, be
present in the liquid, as it is by the oxi.
dation of this agent that the acid is pro-
duced. The series of changes which oc.
cur when sweet liquids are transformed
over into vinegar are ola complex nature,
and somewhat difficult of being made
plain TO the general reader, but we will
endeavor In as brief and comprehensive
manner as possible to point out these
changes.


In order that the acid may be formed,
there are two Preventative processes nee
essary; first the vinous, by which alcobo