CHAPTER XI.
OF THE ROOM FOR DISTILLATION.

We have hitherto considered the liquor as containing only principles
upon which the air has no action, and from which it can only extract
some watery vapors; and, in fact, all those principles contained in
the liquor are fixed. The action of the fire may concentrate, but not
volatilize them.[Pg 27]

The liquor is now changed by the fermentation; it contains no longer
the same principles, but has acquired those which it had not, which
are volatile, and evaporate easily. They must therefore be managed
carefully, in order not to lose the fruits of an already tedious
labor. The spirit already created in the fermented liquor, must be
collected by the distillation; but in transporting it to the still,
the action of the external air must be carefully avoided, as it would
cause the evaporation of some of the spirit. A pump to empty the
hogsheads, and covered pipes to conduct the liquor into the still, is
what has been found to answer that purpose. A good distilling
apparatus is undoubtedly the most important part of a distillery. It
must unite solidity, perfection in its joints, economy of fuel,
rapidity of distillation, to the faculty of concentrating the spirit.
Such are the ends I have proposed to myself in the following
apparatus.

The usual shape of stills is defective; they are too deep, and do not
present enough of surface for their contents. They require a violent
fire to bring them to ebullition; the liquor at bottom burns before it
is warm at the top.

My still is made upon different principles, and composed of two
pieces, viz. the kettle, and its lid. The kettle, forming a long
square, is like the kettle of infusion, already described, and only
differs from it in being one foot deeper. The lid is in shape like an
ancient bed tester; that is to say, its four corners rise into a sharp
angle, and come to support a circle 16 inches diameter, bearing a
vertical collar of about two inches. This collar comes to the middle
of the kettle, and is elevated about 4 feet from the bottom. The lid
is fas[Pg 28]tened to the kettle. The collar receives a pewter cap, to
which is joined a pipe of the same metal, the diameter of which
decreases progressively to a little less than 3 inches: this pipe, the
direction of which is almost horizontal, is 5 feet long.

My still, thus constructed, is established upon a furnace like that of
the infusion room. I observe that the side walls are only raised to
the half of the height of the kettle. A vertical pipe is placed on the
side opposite to the pewter one, and serves to fill up the still: it
is almost at the height of the fastening of the lid, but a little
above. On the same side, on a level with the bottom, is a pipe of
discharge, passing across the furnace: this pipe must project enough
to help to receive or to direct the fluid residue of the distillation;
its diameter must be such as to operate a prompt discharge of the
still.
OF THE URNS.

These are copper vessels, thus called from their resembling those
funeral vases of the ancients. Mine have a bottom of about 18 inches
diameter; they are two feet high, have a bulge of 6 inches near the
top, and then draw in to form an overture of about 8 inches.

On one side, towards the top, there is a copper pipe 2 inches
diameter, projecting externally 2 or 3 inches, and bent in an elbow:
it enters the internal part of the urn, and descends towards the
bottom, without touching it; there it is only a slight curve, and
remains open.

The external part of that pipe is fitted to receive the pewter pipe of
the still; they are made so as to enter into one another, and must fit
exactly. The round opening at the top of the urn receives a cap with a
pewter pipe, made like that of the still. It is likewise five[Pg 29]
feet long, and its size in proportion to the opening: this goes and
joins itself to the second urn, as the still does to the first. The
pipe of this second goes to a third, and the pipe of this last to the
worm. The three urns bear each a small pipe of discharge towards the
bottom.

This apparatus must be made with the greatest care. Neither the
joints, the different pipes of communication, nor the nailings, must
leave the smallest passage to the vapors. The workman must pay the
greatest attention to his work, and the distiller must lute exactly
all the parts of the apparatus that are susceptible of it: he must be
the more careful as to luting it, as this operation is only performed
once a week, when the apparatus is cleaned. At the moment of the
distillation, the master or his foreman must carefully observe whether
there is any waste of vapors, and remedy it instantly. The still and
urns ought to be well tinned.
CHAPTER XII.
EFFECTS OF THIS APPARATUS.

Although the still might contain 400 gallons, there must be only 200
gallons put into it: the rest remaining empty, the vapors develops
themselves, and rise. In that state, the vinous liquor is about one
foot deep, on a surface of 20 feet squa hence two advantages—the
first, that being so shallow, it requires but little fuel to boil; the
second, that the extent of surface gives rise to a rapid evaporation,
which accelerates the work. This acceleration is such, that six
distillations might be obtained in one day. The spirit contained in
the vinous liquor rises in vapors to the lid of the still,[Pg 30]
there find the cap and its pipe, through which they escape into the
first urn, by the side pipe above described, which conducts them to
the bottom, where they are condensed immediately.

But the vapors, continuing to come into the urn, heat it
progressively: the spirituous liquor that it contains rises anew into
vapors, escapes through the cap and pipe, and arrives into the second
urn, where it is condensed as in the first. Here again, the same cause
produces the same effect: the affluence of the heat drawn with the
vapors, carries them successively into the third urn, and from thence
into the worm, which condenses them by the effects of the cold water
in which it is immersed.

The urns, receiving no other heat than that which the vapors coming
out of the still can transmit to them, raise the spirit; the water, at
least the greatest part of it, remains at the bottom: hence, what runs
from the worm is alcohol; that is, spirit at 35°. It is easily
understood how the vapors coming out of the still are rectified in the
urns, and that three successive rectifications bring the spirit to a
high degree of concentration: it gets lower only when the vinous
liquor draws towards the end of the distillation. As soon as it yields
no more spirit, the fire is stopped, and the still is emptied in order
to fill it up again, to begin a new distillation.

Each time that the vinous liquor is renewed in the still, the water
contained in the urns must be emptied, through the pipes of discharge
at the bottom.

Metals are conductors of the caloric. The heat accumulated in the
still, rises to the cap, from whence it runs into the urns: with this
difference—that the pewter, of which the cap and pipes are made,
transmits less[Pg 31] caloric than copper, because it is less dense:
and that bodies are only heated in reason of their density.

However, a great deal of heat is still communicated to the worm, and
heats the water in which it is immersed. I diminish this inconvenience
by putting a wooden pipe between the worm and the pipe of the third
urn. Wood being a bad conductor of caloric, produces a solution of
continuity, or interruption between the metals. The wood of this pipe
must be soft and porous, and not apt to work by the action of the
fi however, to avoid its splitting, I wrap it up in two or three
doubles of good paper, well pasted, and dried slowly. This pipe is one
foot long, and hollowed in its length, so as to receive the pewter
pipe of the third urn at one end, and to enter the worm at the other;
thereby the worm is not as hot, since it only receives the heat of the
vapors which it condenses.

Notwithstanding all these precautions, it heats the water in which it
is immersed after a length of time; and whatever care may be taken to
renew it, all the vapors are not condensed, and this occasions a loss
of spirit. I obviate this accident, by adding a second worm to the
first: they communicate by means of a wooden pipe like the above. The
effect of this second worm, rather smaller than the first, is such,
that the water in which it is plunged remains cold, while that of the
first must be renewed very often. By these means, no portion of vapors
escape condensation. The liquor running from the worm is received into
a small barrel, care being taken that it may not lose by the contact
of the air producing evaporation.