IMPROVEMENTS IN GAS COOKING STOVES
Year: 1868

page_text: LETTERS PATENT to Charles de Berguc, of No. 10, Strand, in the
City of Westminster, Engineer, for the Invention of "IMPROVEMENTS
IN GAS COOKING STOVES."
Sealed the 12th March 1869, and dated the 15th September 1868.
PROVISIONAL SPECIFICATION left. by the said Charles de Bergue at
the Office of the Commissioners of Patents, with his Petition, on
the 15th September 1868.
I, CHARLES DE BERGUE, of No. 10, Strand, in the City of Westminster,
Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN GAS COOKING STOVES," to be as follows:-
The Invention consists in constructing gas cooking stoves with a
combustion chamber so separate or distinct from cooking chamber as
that grease or droppings from the latter may not fall into it, and so
arranged with regard to the admission or entry into it of flame and air
as that the flame may enter in a number of separate jets or otherwise
surrounded by air with the object of as nearly as may be obtaining
perfect combustion and a current of highly heated air (free from smoke,

page_text: smell, and taste of gas) through and from combustion chamber laterally
into cooking chamber, the latter having a grid within it, and its top or
roof being made of a hollow curved form to reveberate or deflect the
heat on to upper surface of grid (or whatever may lie thereon,) the
grid lying in one of two positions, namely, either in a horizontal position
or nearly so, and about level with bottom edge of the mouth of
combustion chamber where the said mouth opens into cooking chamber,
in which case the heat will pass over grid and act chiefly upon the
upper surface or otherwise, the grid lying in an inclined position in the
cooking chamber with upper end near to top of said mouth at the said
opening, in which case the heat will act chiefly upon the under surface,
but so much as passes through or over grid will be deflected upon the
upper surface, and the direct straight line of current from the said
mouth to the "bridge" herein-after mentioned will lie through or cross
the grid when in such inclined position; and in either case the bottom
of edge of deflecting roof at the part farthest from combustion chamber
being made somewhat lower or below the level of the top of the said
mouth (or otherwise) and forming "bridge" under which the current
of heated air must pass off or away from the stove. And a removeable
pan being placed in cooking chamber beneath the grid to collect the
grease or droppings and to form a closed bottom to the cooking
chamber.
And the means by which the Invention may be carried into effect
is as follows:-The combustion chamber may be inside of or ontside or
partly inside and partly outside of case of cooking chamber, and may
be a curved passage way for heated air and of rectangular section
tapering and widening from a narrow width at position of gas jets or
flame to exit, or mouth, or entry into cooking chamber. The grid may be
(and the term is to be understood herein as including) bars, spikes,
hooks, box, dish, or any holder or support for the meat or article to be
cooked. The lower end of grid or end farthest away from combustion
chamber may be at a short distance immediately or nearly so under
lowest portion of curved roof. A top cover to casing may be used, and
in and through the flue thus constituted between this and upper
surface of deflecting roof the heated air may pass to exit through the
casing, and such top cover may form a "hot plate" for cooking or
heating, and may have removable lids or covers to openings therein
intended for saucepans or other vessels fitted to or placed over them.
When the moveable pan is used (as it may be) as a holder or support

page_text: for article to be cooked without bars, grating, or hooks above it, it is or
becomes a "grid" within the definition of the term as herein-before
explained.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles de Bergue in the Great Seal Patent
Office on the 15th March 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
DE BERGUE, of No. 10, Strand, in the City of Westminster, Engineer,
send greeting.
"
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of September, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Charles de Bergue, Her special licence
that I, the said Charles de Bergue, my executors, administrators,
and assigns, or such others as I, the said Charles de Bergue,
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,
usc, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN GAS COOKING STOVES," upon the condition (amongst
others) that I, the said Charles de Bergue, my executors or adminis-
trators, 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 per-
formed, 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 I, the said Charles de Bergue, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, that is to say :-
The Invention consists in constructing gas cooking stoves with a
combustion chamber so separate or distinct from cooking chamber as

page_text: that grease or droppings from the latter may not fall into it, and so
arranged with regard to the admission or entry into it of flame and air
as that the flame may enter in a number of separate jets (or otherwise)
surrounded by air with the object of as nearly as may be obtaining
perfect combustion and a current of highly heated air (free from smoke,
smell, and taste of gas) through and from combustion chamber laterally
into cooking chamber, the latter having a grid within it, and its top or
roof being made of a hollow curved form to reverberate or deflect the
heat on to upper surface of grid (or whatever may lie thereon), the grid
lying in one of two positions, namely, either in a horizontal position or
nearly so, and about level with bottom edge of the mouth of combustion
chamber, where the said mouth opens into cooking chamber, in which
case the heat will pass over grid and act chicfly upon the upper surface
or otherwise, the grid lying in an inclined position in the cooking
chamber with upper end near to top of said mouth at the said opening;
in which case the heat will act chiefly upon the under surface, but so
much as passes through or over grid will be deflected upon the upper
surface, and the direct straight line of current from the said mouth to
the "bridge" herein-after mentioned will lic through or across the grid.
when in such inclined position. And in either case the bottom of edge
of deflecting roof at the part farthest from combustion chamber being
made somewhat lower or below the level of the top of the said mouth (or
otherwise) and forming "bridge" under which the current of heated air
must pass off or away from the stove; and a removeable pan being
placed in cooking chamber beneath the grid to collet the grease or
droppings and to form a closed bottom to the cooking chamber.
The accompanying Drawings illustrate the manner in which the said
Invention is to be and may be performed.
Figure 1 is a vertical section and Figure 2 external front elevation
of improved stove constructed with improved separate combustion
chamber, and in such a manner as to comply with both of the alterna-
tives above set forth as respects the horizontal and inclined positions of
the grid, the inclined position being that represented; Figure 3 is a
horizontal section or plan view with top cover, curved roof, and doors
removed.
a is a light cast-iron case or box supporting and containing the entire
apparatus, for which purpose it is as represented cast with lugs or
fittings to receive and hold the several parts in their proper places;

page_text: b, b, are handles for lifting the stove; and c, top cover to same herein-
after referred to; d, d, are doors on front of case for insertion and
removal of pan and grid and articles to be cooked; e, in Figure 1, is the
combustion chamber which as represented is placed entirely within the
casc, although it might and may (if desired) be so shaped as to extend
partly outside of same; it is for convenience formed by the space
between two cast-iron pieces or plates e* and e³ extending across the
apparatus, and specially curved or shaped and disposed to constitute a
curved passage way (for the heated air) of rectangular section tapering
and widening from a narrow width at entry of gas jets or flame at e³ to
exit or mouth, or entry e into cooking chamber f. Figure 4 is a
detached cross section of the plates e* and e* (separated,) and Figure 5,
longitudinal elevation of them (together), the. plate e being shewn as
partly broken off or removed. From these Figures it will be seen that
the plate ex has flanges at the ends which serve to support it and
determine its proper position in the case by fitting against the projections
a*, a*, and which (flanges) are so curved or shaped on the front edge as
to afford a support to the plate e. The combustion chamber is thus
perfectly distinct and separate from the cooking chamber. g is the grid
or support for articles to be cooked, and is a grease pan on which it
rests, the two being removeable either together or separately on opening
the doors d, d; a' is a grooved fitting cast on the case, and e³ another
grooved fitting on the plate e³, and in these the pan h slides. This
method of fitting effectually makes the pan to serve as a closed bottom
to cooking chamber, that is to say, closing the draft into the cooking
chamber otherwise than through the combustion chamber; h* is handle
of pan.
The grid is formed at one end with long feet g*, g*, the
bottom ends of which rest in small holes in the top edge of the pan made
for their reception, and with shorter feet 93, 9³, presented upwards; it
is constructed of wrought-iron bars (or they may be of cast iron) tinned
all over, and with frame so shaped and the feet so disposed that it may
lie either in the inclined position shewn in the Figures 1 and 3 and also
in the corresponding detached Figure 6 (shewing pan, grid, and roof), or
being turned upside down may lie in a horizontal position or nearly so,
the two long feet g*, g*, with which it is furnished being then presented
upwards as scen (one of them) in the detached transverse section 7 and
in dotted lines in the Figure 1. is the curved reverberating roof which
is reversible end for end, so as to occupy one or other of the intended two
positions by full and dotted lines shewn in the Figure 1, and also by the

page_text: Figures 6 and 7 respectively to correspond with the inclined and
horizontal positions of the grid respectively; /* is a flange on the back of
the curved roof; as, a³, are lugs or projections cast on the inner sides
of the case for supporting one end of reverberating roof, the other
end resting on the upper edge of the plate e*. When the grid is
inclined its upper end lies at about the height of the top edge of
the mouth e* of the combustion chamber, where it opens into cooking
chamber, in which case the heat will act chiefly upon the under surface;
but so much as passes through or over grid will (by the roof) be deflected
upon the upper surface, and the direct line of current from the said mouth
to the bridge at h* will be through or across the grid, the bridge being
formed by one end or edge of the reversible roof; and when the grid is
placed in the horizontal position it is about level with the bottom of the
said mouth of the combustion chamber, in which case the heat will pass
over grid and act chiefly upon the upper surface. The lower end of grid
or end farthest from combustion chamber is placed at a short distance
from and nearly under the bridge at h*. m is removeable gas pipe
pierced with jet holes kept facing the mouth of combustion chamber
at e³ by its bent form and the manner in which it is supported in holes
in the case at a', a', and lug at a³. m* is tap with nozzle for receiving
the end of a flexible gas supply pipe. Beneath the doors d, which do
not completely close the bottom of the opening in front of case is the
inlet for air, and thence the current passes through the combustion and
cooking chambers and under the bridge, and thence over the curved
reverberating roof and between it and the top cover c to opening or
outlet at c* (see Figure 1), the said cover forming a "hot plate" for
cooking or heating, and if desired having one or more removeable lids or
covers to openings therein intended for saucepans or other vessels, which
may be fitted to or placed over them. I would remark that the materials
above specificd are not essential, but that these may be varied; the
case may be of wrought iron and the plates ex, e, forming the com-
bustion chamber, as also the curved roof 7, and the grease pan h, which
it is intended to make of enamelled cast iron, may if preferred be made
of glazed earthenware; and the grid which is of wrought iron may be
made of cast iron. Also that the meaning of the term "grid" as herein
employed is to be understood (so far as not inconsistent with the context)
as including bars, spikes, hooks, box, dish, or any holder or support
for meat or article to cooked; and that the stove may be constructed
without bars, grating, or hooks above the grease pan, in which case the

page_text: said pan may if desired support or hold the meat or article to be cooked.
And it is to be understood that the Invention embraces any form of
gas cooking stove, in which the combustion and cooking chambers are
separate or distinct, as defined in the earlier part of this Specification,
without of necessity including the combination of the deflecting roof,
the grid, and the grease pan, or any or all of them, as herein.set forth
and described.
In illustration of the same intended varieties in the construction two
further Figures or Diagrams are shewn in the Drawing, both repre-
senting circular and upright stones, which, though drawn to a small
scale, are intended more especially for cooking more or larger articles at
one time than the stove firstly described.
Figure 8 is a half elevation and half section of stove suitable for
roasting. Any suitable means of supporting the meat being adopted,
and the grid shewn may be omitted or supplied, in which latter case it
may serve to support the articles to be cooked. The case, which may be
of either wrought or cast iron, is formed with an annular combustion
chamber e completely around it, excepting such few interruptions of the
continuity as are requisite to support the upper upon or over the lower
portion. Or the said chamber need not necessarily extend completely
around the stove, but may if wished be formed at intervals only. p is an
inclined guard plate on the interior, the more effectually to prevent
grease from dropping or spurting into the combustion chamber.
Figure 9 is a sectional view of a stove somewhat similar to the last,
but fitted up with a number of grids or shelves, and intended more
especially as an oven for baking. The shelves may revolve to bring any
part opposite to a door in the case. The jets of gas flame are in this
Figure shewn as presented upwards, instead of laterally as in Figure 8,
and in each Figure the form of the combustion chamber is adapted
accordingly. In Figure 9 a series of guards p are represented, the lower
ones, which may become much heated, shielding the top guard from
such excessive heat, so as to prevent charring or burning any grease
which may fall upon the top guard.
In conclusion, I would remark generally with respect to the Invention
that the gas instead of being supplied to the stove through perforations
or holes in the side of a pipe, may be supplied through separate little
tubular jets jutting out from the supply pipe, or through a continuous
slit or opening to produce a continuous flat flame, or perforations or

page_text: holes if adopted may be placed so close as to produce a continuous flame,
or the gas may be made to enter in any convenient way provided it be
well surrounded by air at the entry, so as to ensure as nearly as may be
its complete and perfect combustion.
In witness whereof, I, the said Charles de Bergue, have hereunto 5
set my hand and seal, this Twelfth day of March, in the year
of our Lord One thousand eight hundred and sixty-nine.