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THE
COMPLETE
PRACTICAL
DISTILLER.
quantity
of
water
of
fixed
temperature
passing
through
the
cooler
in
a
given
time.
It
is
necessary
that
the
fire
should
be
regulated
in
such
a
manner
that
the
quantity
of
vapour
produced
should
be
neither
greater
nor
less
than
that
which
at
the
same
time
may
be
condensed
by
the
application
of
cold.
The
failure
of
attention
to
this
circumstance
(particu-
larly
in
the
distillation
of
spirituous
liquors)
may
pro-
duce
the
following
inconveniences
:
—
First,
if
the
fire
is
too
violent,
a
great
quantity
of
the
condensed
vapours
will
pass
from
the
worm
into
the
external
air,
and
occa-
sion
the
loss
of
the
matter
distilled,
and
also
of
the
fuel.
Secondly,
if
the
fire
or
heat
is
diminished
too
soon,
the
condensation
will
produce
a
vacuum
in
the
worm
and
in
the
alembic,
which,
not
being
proportionably
filled
by
the
fresh
vapour,
will
admit
the
entrance
of the
external
air,
and
impede
both
operations
;
and,
lastly,
will
carry
with
it
a
part
of
the
vapours,
and
occasion
loss
of time,
and
also
of
the
matter
distilled.
To
remedy
these
defects,
and
at
the
same
time
provide
simple
and
eflPectual
means
for
indicating
the
exact
state
of
the
heat
every
instant,
an
instrument
has
been
invented
which
may
be
adapted
to
any
distillery
or
apparatus,
and
is,
in
reality,
nothing
more
than
an
application
of
known
and
practical
princi-
ples.
This
ingenious
machine
possesses
another
singular
advantage
;
namely,
that
in
intercepting the
communica-
tion
of
the
atmospheric
air,
the
products
of
the
distillation
are
more
abundant
and
perfect;
for,
in
proportion
as
the
vapours
condense,
a
vacuum
is
formed
in
that
part of
the
apparatus
into
which
the
vapours
are
drawn,
in
the
same
manner
as
by
the
pump
:
they
are
also
less
compressed