A NEW OR IMPROVED BAKING OVEN
Year: 1862

page_text: LETTERS PATENT to Paul Gondolo, of 29, Boulevart St. Martin, Paris,
in the Empire of France, Merchant, for the Invention of "A NEW OR
IMPROVED BAKING OVEN."
Sealed the 29th August 1862, and dated the 12th March 1862...
PROVISIONAL SPECIFICATION left by the said Paul Gondolo at the
Office of the Commissioners of Patents, with his Petition, on the 12th
March 1862.
I, PAUL GONDOLO, of 29,, Boulevart St. Martin, Paris, in the Empire of
France, Merchant, do hereby declare the nature of. the said Invention for
"A NEW OR. IMPROVED BAKING OVEN," to be as follows:
My Invention relates to improvements in the construction and method of
heating ovens för baking bread, biscuits, pastry, and other alimentary substances
generally. I heat the ovens by means of a metal or other retort, in which I
burn coke by preference, combustion taking place by means of the air drawn
by the furnace under the bars and by the reverberatory effect of the heating
retort. This retort, which forms the furnace, is furnished with metal flues
circulating under the oven, and communicating with an open space surrounding.
it; the oven consists of a chamber of any suitable form of brick or metal, and
completely closed so as to prevent any products of combustion or heated air
from entering, in such manner that the baking of the articles placed therein is
effected solely by contact with the heated surfaces, and by the radiation of heat.
The furnace and its flues should be entirely free of any brickwork, so as to heat
as much as possible the air which mixes with the products of combustion
dispersed around the oven. The arrangement of the flues may be varied,

page_text: fur-
they may be entirely dispensed with, their purpose being to distribute in a
uniform manner around the oven the heat and products of combustion which
escape from the furnace. Dampers are also placed at each side of the furnace
for directing heat upon the sole, or for causing it to pass off at the dome.
In order to retain the whole of the heat around the oven, I dispense with the
ordinary chimney, and thus have no draught nor entry of cold air. I however
apply a small damper in one side of the brickwork surrounding the oven to
afford an escape for the carbonic acid gas evolved in the combustion. This
small opening is made in one side as above mentioned, instead of at the upper
part as usual with chimnies in such manner, that the gas finds an exit before it
reaches the coke or other fuel, and which would extinguish it. In this manner
the little smoke there is, and a great part of the carbonic acid gas will be
drawn by the heat to the upper part. There being no draught in the
nace it consumes two-thirds less' fuel and the temperature may be raised to
a very great extent, while at same time there is no admission of cold air, nor
current for the escape' of heat. Two or more similar ovens may be superposed;
and heated by the same products of combustion, which after having circulated
under the lower oven should pass to the upper one. In order to obtain
steam to actuate mechanical kneading troughs I adapt the furnace for the
generation of steam by placing one or several heating tubes in the interior, or
they may form the sides thereof. The steam on forming passes thence into a
reservoir contained in the brickwork, having the necessary safety valves and
other adjuncts. If it is required to use steam for any products placed in the
oven, I obtain it by establishing a heating tube of any desired form at back of
the furnace having a tube for conducting' the steam into the oven, I also adapt
another tube in the brickwork for the supply of water in proportion to the
amount of steam required for the oven: "
5.
The annexed Drawings represent various arrangements of my improved
oven. Fig. 1 shows a front elevation of a double oven with a steam generator.
Fig. 2, a transverse vertical section of same on line 1, 2, Fig. 4; Fig. 3, a
longitudinal vertical section on line 3, 4; Fig. 4, a horizontal section on
line 5, 6, Fig. 2; Fig. 5 shows a front elevation of a single oven with steam
generator; Fig. 6, a vertical section of same on line 7, 8; while Fig. 7 shows
a plan of same. The same letters of reference indicate, like parts in all the
Figures seen in different positions."
a, smoke passages of the'. oven furnished at the front part with doors b,
which may be furnished with rollers c, and run in grooves, or be simply
hinged as usual; d, metal or other retort forming the furnace, in which is effected
the combustion of the coke or other fuel supplied thereto; e, f, double doors

page_text: closing the front part of the retort d; g, g, heating tubes uniting in pipe h;
these tubes are placed in retort d, and are heated by the fuel therein; i; fixed
plate of cast-iron carrying the ends of heating tubes g; j, branch flues of sheet
or cast-iron placed in an inclined position; these flues pass under the sole of
the oven and terminate in chimney k, see Figs. 1, 2, 3; 4, furnished with a
damper, the position of which may be regulated from the outside. In Figs. 5,
6, & 7, 'these flues open into the chamber surrounding the oven; l, oven,.
properly so called, consisting of a chamber formed of metal or ceramic plates';
m, lower heating chamber, separated from the upper one n by dampers o. The
latter may, as seen in Figs. 1, 2, 3, & 4, be formed of sheet or other iron
pierced with holes, sliding in a metal partition, also furnished with holes.
When the second chamber is to be heated, said dampers are placed so that
their openings shall coincide with the openings in the plates which carry them;
their position is regulated from outside by means of rods provided with handles.
In Figs. 5, 6, & 7, these dampers are hinged and worked by means of cranks
p, q, opening for the introduction of wood; wood may be burnt in this furnace
in cases where it is necessary that the articles; to be baked should receive the
direct action of the flame. r, Fig. 1, flues for the exit of the steam disengaged
from the substances being baked; they are closed by a damper s, Fig. 1, worked
from outside; t, funnel placed at the front of the oven for the exit of any
gas, flame, or other matter escaping therefrom. I also place a damper on one
side of the oven for the escape of carbonic acid gas; v; boiler, placed at x,
communicating with heating tubes g, g, by means of tube y, furnished with
safety valves 1. 2, flanges cast' on the retort, supporting a cast-iron plate,
where the heating tubes are not placed above the furnace grate; 3, plates for
deflecting heat; 4; dampers placed above the upper heating chamber n, for the
escape of the products of combustion in chamber 5, surrounding the second oven.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Paul Gondolo in the Great Seal Patent Office on the 8th
September 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PAUL
GONDOLO, of 29, Boulevart St. Martin, Paris, in the Empire of France,
Merchant, send greeting.
WHEREAS' Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth-day of March, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of

page_text: Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Paul Gondolo, Her special licence that I, the said Paul Gondolo,
my executors, administrators, and assigns, or such others as I, the said
Paul Gondolo, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "A NEW OR IMPROVED
BAKING OVEN," upon the condition (amongst others) that I, the said Paul
Gondolo, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Paul Gondolo, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
I f
My Invention relates to improvements in the construction and method
of heating ovens for baking bread, biscuits, and other alimentary substances
generally. I heat the oven by means of a metal or other retort, in which
I burn coke by preference, combustion taking place by means of the air drawn
by the furnace under the bars, and by the reverberatory effects of the heating
retort. This retort, which forms the furnace, is furnished with metal flues
circulating under the oven, and communicating with an open space surrounding
it; the oven consists of a chamber of any suitable form of brick or metal, and
completely closed so as to prevent any products of combustion or heated' air
from entering, in such manner that the baking of the articles placed therein
is effected solely by contact with the heated surfaces, and by the radiation of
heat. The furnace and its flues should be entirely free of any brickwork so
as to heat as much as possible the air which mixes with the products of com-
bustion dispersing around the oven. The arrangement of the flues may be
varied, or they may be entirely dispensed with, their purpose being to dis-
tribute in a uniform manner around the oven the heat and products of com-
bustion which escape from the furnace. Dampers are also placed at each
side of the furnace for directing the heat upon the sides, or for causing it to
pass off at the dome. In order to retain the whole of the heat around the

page_text: ..
oven, I dispense with the ordinary chimney, and thus have no draught nor
entry of cold air. I however apply small damper in one side. of the
brickwork surrounding the oven to afford an escape for the carbonic acid
gas senvolved in the combustion. This small opening is made in one side" as
above mentioned instead of at the upper part as usual with chimnies, in such
manner that the gas finds an exit before it reaches the coke or other fuel,
and which would extinguish it. In this manner the little smoke and a great
part of the carbonic acid gas will be collected by the caloric force at the
upper
part. There being no draught in the. furnace it consumes two-thirds less
fuel, and the temperature may be raised to a very great extent, while at same
time there is no admission of cold air, nor current for the escape of heat.
Two or more similar ovens may be superposed, and heated by the same
products of combustion, which after having circulated under the lower oven
should pass to the upper one. In order to obtain steam to actuate the
mechanical kneading troughs, I adapt the furnace for the generation of steam
by placing one or several heating tubes in the interior, or they may form the
sides thereof. The steam on its formation passes thence into a reservoir
contained in the brickwork, having the necessary safety valves and other
adjuncts. If it is required to use steam for any products placed in the oven,
I obtain it by establishing a heating. tube of any desired form at back of the
furnace having a tube for conducting the steam into the oven, I also adapt
another tube in the brickwork for the supply of water in proportion to the
amount of steam required for the oven.
The annexed Drawings represent various arrangements of my improved
ovens. Fig. 1 shows a front elevation of a double oven without a steam
generator; Fig. 2, a transverse vertical section of same. on line 1, 2; Fig. 3,
a longitudinal vertical section of same on line 3; 4; Fig. 4 a horizontal section
of same on line 5, 6, Fig. 2; Fig. 5 shows a front elevation of a single oven
with steam generator; Fig. 6, a vertical section of same on line 7, 8; while
Fig. 7 shows a plan of same.
The same letters of reference indicate like
parts in all the Figures seen in different positions.
a smoke passages of the oven furnished. at the front part with doors b,
which may be furnished with rollers c, and run in grooves, or. be simply
hinged as usual; d, metal or other retort forming the furnace in which
is effected the combustion of the coke or other fuel supplied thereto;
e, f, double doors closing the front part of retort d; g. 9, heating tubes,"
uniting in pipe h; these tubes are placed in retort d, and are heated by
the fuel therein; i, fixed plates of cast iron, carrying the ends of heating
tubes g; j, branch flues of sheet or cast iron, placed in an inclined

page_text: position; these flues pass under the sole of the oven, and terminate in
chimney k, see Figs. 1, 2, 3, 4, furnished with a damper, the position of which
may be regulated from the outside. In Figs. 5, 6, and 7; the flues open into
the chamber surrounding the oven; 1, oven, properly so called, consisting of a
chamber formed of metal or ceramic plates; m, lower heating chamber,
separated from the upper one n, by dampers o. The latter may as seen in
Figs. 1, 2, 3, 4, be formed of sheet or other iron pierced with holes, and
sliding in a metal partition, also furnished with holes. When the second
chamber is to be heated, said dampers are placed so that their openings
shall correspond with the openings in the plates which carry them; their
position is regulated from outside by means of rods provided with handles.
In Figs. 5, 6, & 7, these dampers are hinged and worked by means of
cranks p, q, opening for the introduction of wood; wood may be burnt in this
furnace in cases, where it is necessary that the articles to be baked should
receive the direct action of the flames; r, flues for the exit of the steam
disengaged from the substances being baked, they are closed by a damper;
8, worked from outside; t, funnel placed at the front of the oven for the exit
of any gas, flame, or other matter escaping therefrom. I also place a damper
on one side of the oven for the escape of carbonic acid gas; v, boiler placed
ata, communicating with heating tubes 9, 9, by means of tube y, furnished
with safety valves 1; 2, flanges cast on the retort supporting a cast-iron plate,
where the heating tubes are not placed above the furnace grate; 3, plates
for deflecting heat; 4, dampers placed above the upper heating chamber n,
for the escape of the products of combustion in chamber 5, surrounding the
second oven.
Having described the nature of my Invention, and the manner of per-
forming the same, I declare that what I claim as my Invention to be protected
by the herein-before in part recited Letters Patent is, the arrangement of oven
or chamber, as and for the purposes herein-before described, in which a chamber
kept surrounded by great heat without any current of air.
In witness whereof, I, the said Paul Gondolo, have hereunto set my
hand and seal, this Fifth day of September, in the year of our
Lord One thousand eight hundred and sixty-two.
PAUL GONDOLO. (L.S.)