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TANNIN.
183
barrel
can
be
used
for
the
same
purpose.
(For
fur-
ther
particulars
see
Filtering
Apparatus.)
Boiled
Milk
possesses
decolorizing
properties,
and
is
very
useful in
wines.
A
pint
of
boiled
milk
added
while
warm
to
a
pipe
of
red
wine,
will
discharge
the
color
completely,
rendering
it
transparent.
The
action
of
the
milk
is
mechanical
;
the
particles
of
milk,
combining
with
the
minute
particles
that
con-
stitute
the
coloring,
fall
to
the
bottom
or
subside.
TANNIN.
As
tannin
is
extensively
used
in
one
form
or
another,
viz.
as
tanning
oak
bark,
catechu,
and
terra
japonica,
for
the
bitter
and
astringent
principle
and
coloring
matter
that
it
yields,
which
is
well
adapted
to
brandies,
whiskey,
and
some
wines
it
requires
that
it
should
have
more
than
a passing
notice.
The
term
tannin
was
originally
applied
to
a
principle
existing
in
many
vegetables
having
a
very
astringent
taste,
and
the
property
of
producing
a
white,
floe-
culent
precipitate,
with
a
solution
of
gelatine
and
black
precipitate,
with
the
salts
of
the
sesquioxide
of
iron.
As
obtained,
however,
from
different
plants,
it
was
found
to
exhibit
some
difference
of
properties,
und
chemists
have
recognised
two
kinds
;
one
exist