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Account of American Editions of Fo-
reign Publications.
Art. III.
Essays, Political, Economical, and
Philosophical. By Benjamin Count
Rumford. The first American,
from the third London Edition.
[Continued from p.64, and concluded.]
THE sequel of this essay treats
of various subjects, some cu-
rious and philosophical, and some
of practical importance. We shall
dismiss this publication with the
following particulars.
To facilitate an important change
in the mode of feeding the numerous
objects of charity who were shut up
in the House of Industry, in Dub-
―140―
lin our author constructed a per-
petual oven.
In the centre of a cylindrical
mass of brick-work, about eight
feet in diameter, which occupies
the middle of a large room on the
ground floor, he constructed a
small circular closed fire-place for
burning either wood, peat, turf, or
coals. The diameter of the fire-
place is about eleven inches, the
grate being placed about ten inches
above the floor, and the top of the
fire-place is contracted to about
four inches. Immediately above
this narrow throat, six separate ca-
nals (each furnished with a damper,
by means of which its opening can
be contracted more or less, or en-
tirely closed) go off horizontally,
by which the flame is conducted in-
to six separate sets of flues, under
six large plates of cast iron, which
form the bottoms of six ovens on
the same level, and joining each
other by their sides, which are con-
cealed in the cylindrical mass of
the brick-work: Each of these
plates of cast iron being in the form
of an equilateral triangle, they all
unite in the centre of the cylindrical
mass of brick-work, consequently,
the two sides of each unite in a
point at the bottom of it, forming
an angle of sixty degrees.
The flame, after circulating un-
der the bottoms of these ovens,
rises up in two canals concealed in
the front wall of each oven, and
situated on the right and left of its
mouth, and after circulating again
in similar flues on the upper flat
surface of another triangular plate
of cast iron, which forms the top of
the oven, goes off upwards by a ca-
nal furnished with a damper into a
hollow place, situated on the top of
the cylindrical mass of the brick-
work, from which it passes off in a
horizontal iron tube, about seven
inches in diameter, suspended near
the ceiling of the room, into a chim-
ney situated on one side of the room.
These six ovens, which are con-
tiguous to each other in this mass
of brick-work, are united by their
sides by thin walls made of tiles
about one and an half inches thick,
and ten inches square, placed edge-
wise; and each oven having its se-
parate canal furnished with a regis-
ter, communicating with the fire-
place, any one or more of them may
be heated without heating the others,
or the heat may be turned off from
one of them to the other in conti-
nual succession; and, by managing
matters properly, the process of bak-
ing may be uninterrupted. As soon
as the bread is drawn out of one of
the ovens, the fire may immediate-
ly be turned under it, to heat it
again, while that from under which
the fire is taken is filled with un-
baked loaves, and closed up.
A principal object which he had
in view in constructing this oven,
was to prevent the great loss of heat
which is occasioned in large ovens,
by keeping the mouth of the oven
open for so considerable a length of
time as is necessary for putting in,
and drawing out the bread. As one
of these small ovens contains only
five large loaves, or cakes, it may
be charged, or the bread, when
baked, may be drawn, in a mo-
ment; and during this time, the
other five ovens are kept closed,
and consequently are not losing heat;
one of them is heating, while the
other four are filled with bread in
different stages of the process of
baking.
“When constructed,” continues
the author, “this oven, though I
had no doubt of its being perfectly
well calculated for the use for
which it was principally designed,
—baking oaten cakes, which are
commonly baked on heated iron
plates,—yet I was by no means
sure it would answer for baking
common bread in large thick loaves.
I had not made the experiment.
And though I could not conceive
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that any thing more could be neces-
sary in the process of baking than
heat,—and here I was absolutely
master of every degree of it that
could possibly be wanted, and
could even regulate the succession
of different degrees of it at pleasure,
—I thought it probable that some
particular management might be
required in baking bread in these
metalic ovens, a knowledge of
which could only be acquired by
experience.
What served to strengthen these
suspicions, was a discovery which
had accidentally been made by the
cook of the Military Academy. In
the course of his experiments, he
found that my roaster is admirably
well calculated for baking pies,
puddings, and pastry of all kinds;
provided, however, that the fire be
managed in a certain way; for,
when the fire is managed in the
same manner in which it ought to
be managed in roasting meat, pies
and pastry will absolutely be spoiled.
After repeated failures and disap-
pointments, and after having lost
all hopes of ever being able to suc-
ceed in his attempts, the cook, by
mere accident, as he assured me,
discovered the important secret; and
important he certainly considers it
to be, and feels no small degree of
satisfation, not to say pride, in hav-
ing been so fortunate as to make
the discovery. He must pardon me
if I take the liberty, even without
his permission, to publish it to the
world for the good of mankind.
“The roaster must be well heated
before the pies or pastry are put into it,
and the blowers must never be quite
closed during the process.
“I have lately found that by using
similar precautions, bread may be
perfectly well baked in metalic
ovens, similar to that in the House
of Industry in Dublin.
“Thinking it more than proba-
ble that means might be devised for
managing the heat in such a man-
ner as to perform that process in
ovens constructed on these princi-
ples, and heated from without; and
conceiving that not only a great
saving of fuel, but also several
other very important advantages,
could not fail to be derived from
that discovery, on my return to
Munich from England, in August
last, I immediately set about mak-
ing experiments, with a view to
the investigation of that subject;
and I have so far succeeded in them,
that for these last four months my
table has been supplied entirely
with bread baked in my own house,
by my cook, in an oven construct-
ed of thin sheet-iron, which is
heated (like my roasters) from with-
out;—and I will venture to add,
that I never tasted better bread. All
those who have eaten of it have
unanimously expressed the same
opinion of it. It is very light, most
thoroughly baked without being
too much dried, and I think re-
markably well tasted. The loaves,
which ware made small in order that
they may have a greater proportion
of crust (which, when the bread is
baked in this way, is singularly
delicate), are placed in the oven on
circular plates of thin sheet-iron,
raised about an inch on slender
iron feet. Were the loaf placed on
the bottom of the oven, the under
crust would presently be burnt to a
coal, and the bread spoiled. A
precaution absolutely necessary in
baking bread in the manner here
recommended, is to leave a passage
for the steam generated in the pro-
cess of baking to escape. This
may be done either by constructing
a steam-chimney for that purpose,
furnished with a damper; or simply
by making a register in the door of
the oven.
“I cannot help expressing a wish
that what I have here advanced, may
induce others, especially bakers, who
may find their own advantage in the
prosecution of these interesting and
―142―
important investigations, to turn
their attention to them.
“How exceedingly useful would
my roasters be, and ovens con-
structed on the principles here re-
commended, on shipboard! I have
had frequent opportunities of seeing
how difficult it is, in bad weather, to
cook at sea; and it is easy to imagine
how much it would contribute to
the comfort of seafaring people,
especially at times when they are
exposed to the greatest fatigues and
hardship, to enable them to have
their tables well supplied with warm
victuals.
“In order that the motion of the
vessel might not derange any part
of the apparatus used in the process
of cooking at sea in my roasters,
the form of the roaster should be
that of a perfect cylinder, and the
dripping-pan in which the meat is
placed, should be a longitudinal
section of another cylinder, less in
diameter than the roaster by about
an inch, and suspended on two
pivots in the axis of the roaster, in
such a manner that the dripping-
pan may swing freely in the roaster,
without touching its sides. The
roaster should be placed in the
brick-work, with its axis in the di-
rection of the length of the ship;
and, to prevent the gravy from
being thrown out of the dripping-
pan when the vessel pitches, its hol-
low cavity should be divided into a
number of compartments, by parti-
tions running across it from side to
side.
“The cottage fire-place which I
fitted up as a model, in the court-
yard of the house of the Dublin so-
ciety, was not quite finished when
I left Ireland; but an idea may be
formed, from what was done, of the
general principles on which such
fire-places may be constructed. On
each side of the open chimney fire-
place, (which being small, was
built in the middle of one much
larger, which was constructed to
represent a large open fire-place,
such as are now general in cot-
tages) I fitted up an iron pot on a
peculiar construction, and design-
ed for the use of a poor family in
cooking their victuals. This pot
is nearly of a cylindrical form, about
sixteen inches in diameter, and
eight inches deep: and under its
bottom, which is quite flat, there
is a thin spiral projection, which
was cast with the pot, and serves
instead of feet to it; the turns of
which, when the pot is set down
on a flat surface, form a spiral flue,
in which the flame circulates under
the bottom of the pot. This pro-
jection, which is near half an inch
thick where it is united with the
bottom of the pot, and less than a
quarter of an inch below where its
lower edge rests on the ground, is
about four inches wide, or rather
deep. This projection was made
tapering, in order to its being more
easily cast. To defend the outside
of this pot from the cold air, the
pot is inclosed in a cylinder of thin
sheet-iron, equal in diameter to the
extreme width of the pot at its brim,
just as high as the depth of the pot
and of its spiral flues taken together.
The pot is fastened to this cylin-
drical case by being driven into it
with force, a rim in the form of a
flat hoop, about an inch and an
half deep, and a little tapering, be-
ing cast on the outside of the pot at
its brim, the external surface of
which was fitted exactly into the
top of this cylinder. This projec-
tion is useful, not only in uniting
the pot to its cylindrical case, but
also to keep this cylindrical case at
some small distance from the sides
of the pot, by which means the
heat is more effectually confined.
“To be able to move about this
pot from place to place, it has two
handles which are riveted to the
outside of its cylindrical case; and
it is provided with a wooden co-
ver.”
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