IMPROVEMENTS IN GAS COOKING APPARATUS
Year: 1873

page_text: LETTERS PATENT to Thomas Peacock, of Wood Green, in the County
of Middlesex, Gentleman, and John Chapman Peacock, of Finsbury
Park Road, in the same County, Gentleman, for the Invention of
T
"
PROVISIONAL SPECIFICATION left by the said Thomas Peacock and
John Chapman Peacock at the Office of the Commissioners of
Patents, with their Petition, on the 8th November 1873.
We, THOMAS PEACOCK, of Wood Green, in the County of Middlesex,
Gentleman, and JOHN CHAPMAN PEACOCK, of Finsbury Park Road, in
the same County, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN GAS COOKING APPARATUS," to be as
follows:-
The object of this Invention is to economize the heat derived from the
combustion of gas and thereby to render it more efficient than heretofore
for the cooking of viands, whether by the baking or boiling process. To
this end we make the walls of the oven, and also the top and bottom

page_text: thereof of such a thickness and of such materials as will retard or
prevent the radiation of heat generated within the oven; and we so
ventilate the oven as to ensure the retention at the upper part thereof of
a comparatively quiescent heated atmosphere.
The like result we attain, and by equivalent means, in heating the 5
kettles or saucepans placed on the top of the stove.
The oven we form with an inner lining of sheet iron and with an
outer casing of wood or iron (but preferably of wood), leaving a space
between the casing and the lining, say from one to three inches. This
space we fill with dry powdered lime or other suitable non-conducting 1
material.
When the oven is provided with a swing door for giving access to the
interior we construct the door after the manner of the walls of the
oven.
The oven may when desired be divided horizontally by a removeable 1
shelf or shelves into two or more compartments, which shelves will have
openings in them to allow of the heat ascending from below, but they
will be provided with slides or valves for closing these openings.
The oven we fit with a false bottom of a depth somewhat short of the
depth of the oven, and in rear thereof we place the gas burner, which 2
may be a straight tube with a series of jets. The pipe leading thereto
will rest upon brackets projecting from one side of the oven and leading
out below the door, or the gas pipe may pass through the oven wall.
The door we propose to make somewhat shorter than the opening, which
it covers in order to permit of the free access of air to the space below 2
the false bottom, which air is required for supporting combustion within
the oven.
To give ventilation to the oven we prefer so to shape the lower part
of the door that when closed there will be a gap between it and the side
walls of the oven, and this gap we propose to close by swing shutters. ¿
A similar arrangement will also serve for closing the opening through
which air is admitted to the gas burner.
In place of this arrangement for ventilating the oven the door may be
fitted with a double slide valve at its lower end, and it may fit like an
ordinary door to the front wall of the oven. The heat absorbed by the a
walls of the oven will allow of the completion of the cooking being

page_text: effected without the use of the gas. When however the gas is turned off
the oven must be closely shut to prevent the admission of cold air
thereto or the escape of hot air therefrom.
For heating kettles or saucepans we use any ordinary or approved
burners, which rest on the top plate of the stove. Each burner we
surround with a cylinder, through the lower part of which air is drawn
to support combustion, and concentric therewith we place a cylindrical
or it may be an oval support for the saucepan or kettle. This support is
made by preference of metal, and has openings at its lower end for the
passage of air to the burner and the escape of the gases of combustion
therefrom. This support for the saucepan or kettle is jacketed like the
oven at its upper part, and it is so shaped and proportioned that the
saucepan or kettle will fit snugly therein, and thus prevent the escape
upwards of the heat from the burner. In order the more effectually to
secure this end we jacket the lid of the saucepan or kettle, giving it a
filling of powdered lime or other bad conductor of heat.
In some cases instead of providing the oven with a swing door we
propose to gain access to the oven by giving it a moveable bottom
supported by counterweights. In this case the gas burner may be fitted
to the moveable bottom.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Peacock and John Chapman Peacock in
the Great Seal Patent Office on the 8th May 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
PEACOCK, of Wood Green, in the County of Middlesex, Gentleman,
and JOHN CHAPMAN PEACOCK, of Finsbury Park Road, in the same
County, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of November, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said Thomas Peacock and John Chapman
Peacock, Her special licence that we, the said Thomas Peacock and John
Chapman Peacock, our executors, administrators, and assigns, or such

page_text: others as we, the said Thomas Peacock and John Ohapman Peacock, our
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 5
Ireland, the Channel Islands, and Isle of Man, an Invention for "Iм-
PROVEMENTS IN GAS COOKING APPARATUS," upon the condition (amongst
others) that we, the said Thomas Peacock and John Chapman Peacock,
our executors or administrators, by an instrument in writing under our,
or their, or one of their hands and seals, should particularly describe and 1
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
Scal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that we, the said Thomas Peacock and John Chapman 1
Peacock, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The object of this Invention is to economize the heat derived from the
combustion of gas, and thereby to render it more efficient than hereto- 2
fore for the cooking of viands. To this end we make the walls of the
oven, and also the top and bottom thereof, of such a thickness and of
such materials as will retard or prevent the radiation of heat generated
within the oven, and we so ventilate the oven by an exact regulation of
its air supply and by drawing off the products of combustion at the 2
lowest possible level as to ensure the retention at the upper part of the
oven of a comparatively quiescent heated atmosphere.
The like result we attain, and by equivalent means, in heating the
kettles and saucepans placed on the top of the stove or by independent
apparatus placed at any convenient position in the kitchen or room.
The oven we form with an inner lining, preferably of sheet iron, which
may be either tinned, galvanized, or enamelled, and with an outer casing
of wood or iron (but preferably of wood) leaving the space between the
casing and lining, say from one to three inches. This space we fill with
dry powdered lime or other suitable non-conducting material.
When the oven is provided with a swing door, which is the usual
method of construction for giving access to the interior, it is constructed
after the manner of the walls of the oven.

page_text: Under one arrangement we cause the heated air with the effluvia of
the cooking to pass up the chimney or through a tube into the open air,
and under this arrangement the gas burner is placed on the door, the air
to support combustion is passed to the burner under the door, and an
opening is made at the back of the oven so as to allow the products of
combustion to pass out and to ensure the utmost economy of heat. This
opening is placed low down in the oven, and the products are passed up
and over the surface of the back of the oven by doubling the back and
leaving an air space of the width of the back of the oven, and of from
one to three inches in depth. The products of combustion are gathered
up by a suitable contraction of the form of this air space which leads
into a tube, which is made to pass into the chimney of the room or into
the open air.
The oven may, when desired, be divided horizontally by a movable
shelf or shelves into two or more compartments, which shelves have
openings in them suitably graduated or adjusted to allow the heated air
so to ascend from below as to produce in each compartment an equal
temperature, or they may be provided with slides or valves for regulating
these openings so as to vary the proportionate temperature of the different
compartments. Or the shelves may be made of wire to allow of free
circulation of the heated air and serve as gridirons for the meat to be
placed upon.
When for simplicity and cheapness of construction it is not desired to
ventilate into the chimney of the room the oven is fitted with a false
bottom with a space between it and the back of the oven, and in this
space we place the gas burner, which may be a movable tube with a
series of holes or jets bent to a right angle and resting loosely upon
.brackets projecting from one side of the oven and leading out below the
door, which does not come down so low as the false bottom, or the gas
pipe may pass through the oven wall, or the false bottom is dispensed
with by supplying the burner with air direct through the bottom of the
oven.
The products of combustion pass out in front under the door through
a space left between the door and the false bottom. This form of oven
we also make with the gas pipe on the door and the exit at the back.
In all forms of the oven the gaps or openings in the door or outer
casing which permit of the passage of the products of combustion

page_text: outwards, are closed at will by swing or sliding shutters or valves. A
similar arrangement also serves for closing the openings through which
air is admitted to the gas burners, or the door may cover the whole of
the front of the oven, and may be fitted with a double slide valve at its
lower end.
When the gas is turned off and the valves are shut the heat absorbed
by the walls of the oven will allow of the completion of the cooking
· being effected without the further use of the gas.
When the openings for the exit of the products are closed so as to
prevent any circulation of air then the oven can be used as an ice safe,
and in hot weather meat can be kept fresh by a small quantity of ice
being placed on the top gridiron with a dripping pan placed under it
until the meat is required to be cooked.
In heating the contents of kettles or saucepans any ordinary or
approved burners may be used, and may be attached to the top of the
stove, or may be fixed inside the air tube of each jacket. The jackets
are made of various sizes separate from but to fit the various kettles or
saucepans, and are removable (with or without the gas burners) from the
stove.
The jacket which forms a support for the saucepan or kettle is formed
externally of a cylindrical or oval tube of metal, in the centre of which is
placed a smaller cylinder or air tube enclosing the burner. The burner is
placed a little below the top of this cylinder, which is placed at a suitable
distance from the bottom of the saucepan. The air tubo is raised about
an inch from the level of the bottom of the outer tube and is held in
position by a metal diaphragm which extends from its bottom edge to
the outer tube. It is supplied with air by holes in the outer tube. In
the latter, immediately above the diaphragm, are exit holes for the pro-
ducts of combustion. The lime or non-conducting material is packed
between the outer tube and another tube which is joined to it inside
above the exit holes, and tapers therefrom conically to the top, forming
the immediate support in which the saucepan fits snugly, preventing the
escape upwards of the heat from the burner. The space for the non-
conducting materials thus increases in thickness up to the top. The inner
tube is carried up a little higher than the outer tube, and is connected with
it by sheet metal which slants slightly from the inner tube to the outer, so
as to throw off the boiling over of the pot. The kettle or saucepans being
formed as usual with parallel sides the heated air circulates not only

page_text: over the bottom but all round the sides of the saucepan or kettle, finally
passing out below the level of the gas burner through openings made in
the outer jacket as before described.
The lids of the saucepans or kettles are jacketed with a filling of
powdered lime or other bad conductor of heat.
The kettle for heating water for tea making and such like purposes is
made so that the lid used for the saucepans will suit it also. To allow
of a spout being inserted without unduly leaving the side of the kettle
unprotected by the jacket, and also to allow the water to be poured out
without any spilling, the kettle has half (more or less) of the opening
for the lid closed by a diaphragm thus
Ө
and this diaphragm
is sloped upwards towards the rim of the kettle, so as to allow space
under it for a flat spout. The lid is made with one side of its bottom or
lower jacketed part sloped to fit this diaphragm.
As the delicate lambent flame of the ordinary air and gas burner
cannot be brought (by turning down the gas) to a very low point
without going out, we construct our burners for the combustion of
mixed gas and air thus:-Against the wire guaze top of the air and gas
burner and in the centre we bring up from the bottom a small cylinder,
only one inch in diameter, into which we pass another gas pipe with
regulating cock. The flame from the whole of the gauze surface pro-
ceeding from the double gas supply can be thus used for the boiling up,
and the larger supply being turned off the simmering or slow boiling
can be continued by means of the small central flame, which being con-
centrated in position does not run about the guaze surface or go out.
The result of this arrangement is a very great economy of gas in keeping
the pot boiling.
When we do not burn mixed air and gas, we use concentric ring
burners, the holes in which are appropriately graduated in size according
to their position, and the supply of gas regulated so as to ensure a per-
fectly uniform height to all the various flames, and the impossibility of
their smoking under any ordinary pressure.

page_text: Figure 4, sectional view of stand, with kettle therein.
Figure 5, side elevation of apparatus, with stand and kettle in its
place on top of same.
Figure 6 shows by diagram how the gas burners are fixed at the
back of the apparatus.
A represents external casing; B, internal casing, composed of by
preference any suitable metal; C, packing of material, herein-before
described, which is packed between the internal and external casing,
as shewn in Figure 3. The packing need not extend further than
within six inches from the bottom of the cooking chamber. The gas
jets D are fitted to the door E (such door having internal and external
casing, with packing as the body of the apparatus) and are enclosed
in a case F open at the top. The space between the outer and inner
casings of the door for about six inches from the bottom is not packed,
and is open to exterior air at the bottom. Through this channel, and
through holes G in the internal casing of the door, the air to support
combustion is conveyed to the gas jets D, and the heated products
circulate all round the oven and finally make their exit, cooling as
'they descend through holes H into the flue I to chimney J.
The back of the apparatus is, as will be seen (in Fig. 3) formed with
a double casing, with a space I between them; such forming the flue,
as before explained.
The gas to the jets is conveyed by a suitable pipe, but we prefer to
fit to our apparatus an arrangement of pipes K. The pipe K¹ is for
the inlet of gas, the outlets being fitted with taps K". The boiling
apparatus is shewn in Figure 4. The interior between the outer case
and the inner conical case being packed with material, as before
described. The holes M. are for the exit of products; N aro gas burners;
O, kettle,
In Figure 6 the fresh air travels to the burners through the space
formed between the bottom a and the false bottom 6 of the oven, and
after circulating through the oven passes out through the opening c
left under the door of the apparatus. This form is made of same
character as that shewn in Figure 3.

page_text: Having now particularly described and ascertained the nature of
our said Invention, and in what manner the same may be performed
or put in practice, we hereby declare that we claim the Invention
of improvements in gas cooking apparatus, as herein-before set
forth and described, wherein the following are novel and important
features:-
The general form, construction, and arrangement of cooking stove
and boiling apparatus, with their combination of non-conducting
casings, the mode of introduction and regulation of supply of gas,
and the system of regulated withdrawal of the products of combustion
from the lowest part of the cooking space.
The special construction of concentric burners for the combustion
of air and gas.
The packing of the lids of the saucepans.
The form and construction of the kettle for boiling water.
It being understood that we do not limit ourselves to the precise
details of construction or arrangement provided, the important features
of our Invention are substantially adopted.
In witness whereof, we, the said Thomas Peacock and John
Chapman Peacock, have hereunto set our hands and seals, this
Sixth day of May, in the year of our Lord One thousand eight
hundred and seventy-four.
THOMAS PEACOCK.
(L.S.)
JOHN CHAPMAN PEACOCK. (L.S.)
5 Witness,
0
T. MORGAN,
Secretary,
Inventors' Patent Right Association, Limited,
21, Cockspur Street.,
S. W.