29 / 230
CONTINUOUS
DISTILLATION.
29
hol.
when
the
spirit
is
required
to
be
of
great
strength.
This
rectification
is
effected
in
the
following
way
:
The
vapours
condensed
by
the
condenser
Q
I
pass
through
the
tube
hj
into
the
refrigerator,
when
they
are
sufficiently
rich
;
but,
if
this
is
not
the
case,
they
may,
by
means
of
the
retrograding
pipes
g
i
and
g
j,
be
brought
back,
whole
or
only
in
part,
to
the
rectifier;
there
they
meet
with
obstacles
in
their
fall
similar
to
those
opposed
to
the
falling
of
wine
in
the
column.
These
low
wines
undergo
thus
an
analysis
similar
to
that
which
the
wine
undergoes
in
the
column
;
that
is
to
say,
that
these
low
wines
arrive
in
the
rectifiers
much
richer
in
alcohol
than
the
wine
that
is
worked,
and
that
they
leave
this
part
of
the
apparatus
in
a
state
of
rich-
ness
about
equal
to
that
of the
vinous
vapours.
Thus
it
is
evident
that
these
low
wines
have
been
deprived
of
their
alcohol
in
favour
of
the
spirituous
vapours
by
which
they
have been
analyzed.
It
is
thus
that,
by
means
of
the
rectifier
and
of
the
retrograding
pipes,
the
strength
of
the
spirits
may
be
regulated.
It
has
already
been
seen
with
what
art
and
ingenuity
this
apparatus
has
been
con-
structed,
and
how
successfully
it
fulfils
the
principles
that
have
been
established
on
the
art
of
distillation.
In
fact,
those
vapours
that
are
the
most
watery
are
always
in
contact
with
the
weakest
part
of
the
wine
;
and
reci-
procally,
those
that
are
charged
with
the
greatest
quantity
of
alcohol,
when
they
are
to
be
rendered
richer,
are
always
in
contact
with
the
richest
liquid.
Thus
every
thing
con-
curs
to
deprive
the
wine
of
its
alcohol
without
ever
ren-
dering
it
richer
itself,
and
to
dephlegm
the
vapours without
ever
mixing
them
with
liquids
poorer
in
alcohol
than
3*