IMPROVEMENTS IN APPARATUS FOR COOKING
Year: 1880

page_text: LETTERS PATENT to Saint John Vincent Day, of Glasgow, in the County of
Lanark, North Britain, Civil Engineer, for an Invention of "IMPROVEMENTS
IN APPARATUS FOR COOKING." A communication from abroad by Daniel
MacAlpin, of Philadelphia, in the State of Pennsylvania, United States of
America
PROVISIONAL SPECIFICATION left by the said Saint John Vincent Day at
the Office of the Commissioners of Patents on the 16th October 1880.
"
SAINT JOHN VINCENT DAY, of Glasgow, in the County of Lanark, North
Britain, Civil Engineer. "IMPROVEMENTS IN APPARATUS FOR COOKING." [A com-
munication from abroad by Daniel MacAlpin, of Philadelphia, in the State of
Pennsylvania, United States of America.]
The object of the said Invention is to provide means for use with an ordinary
portable furnace, whereby the dissemination of odours due to cooking operations is
prevented and the furnace is adapted for baking.
A portable furnace of the usual construction, having above the fire-pot a flue
communicating with the stove-pipe, and having in the top plate the usual opening
for the reception of a culinary vessel, has fitted in this opening the lower end of an
outer cylindrical casing, the upper end of which is closed by a cap, the lower end
being open to the flue. To a flange surrounding the upper edge of the fire-pot is
fitted the lower end of an inner cylindrical casing open at the lower end to the fire,
and in the upper end of which is an opening communicating with the space
between itself and the outer casing, which is concentric with, but somewhat
less in diameter than, the outer casing, so that when the two casings are
applied to the furnace, the products of combustion are compelled to ascend the
chamber enclosed by the inner casing, and then to descend the annular chamber
between the two casings before they reach the flue and the discharge-pipe.
In the performance of culinary operations, such as boiling, frying, broiling, the
double casing is used for the purpose of carrying off to the chimney the odours
given off during the cooking operation, the utensil containing the food to be cooked
being enclosed by the inner casing, so that the odours are caused to ascend with
the products of combustion in the inner chamber and descend the outer annular

page_text: chamber, escaping finally through the flue and discharge-pipe to the chimney. When
the apparatus is to be used for baking, however, the pans containing the dough are
supported one above another by light frames, and the series of pans are enclosed by
another innermost casing having an annular space between its outer side and the
inner side of the before mentioned inner casing, which I will now call the second
casing. The lowest pan of the series rests upon a flanged plate to which the lower
end of the innermost casing is fitted.
A tile, or slab, of fire-brick, or other refractory material, intervenes between the
said flanged plate and a plate which is supported by feet resting upon a perforated
annular plate, the latter being also provided with feet which bear on the upper
edge of the fire-brick lining of the fire-pot.
The outer and second casings being applied so that the second casing surrounds
the innermost casing and the supporting plates, the products of combustion are
caused to ascend the annular space between the innermost and second casings,
thereby imparting a high degree of heat to the said innermost casing and to the air
contained therein before descending the annular chamber between the second and
outer casings and escaping to the chimney.
The full effect of the fresh products of combustion is utilized in heating the
innermost casing and its contents, there being very little loss of heat by radiation,
owing to the fact that the spent products of combustion descending the annular
chamber between the outer and second casings form an air-jacket, and prevent
the chilling of the inner casing by direct contact of cold air therewith.
The tile or slab of refractory material beneath the plate, upon which the lower
pan rests, prevents the imparting of such a high degree of heat to the said plate as
would cause the burning of the dough in the bottom pan of the series. *
The furnace has short feet, which are fitted into sockets in the upper. ends
of the legs of the furnace, whereby the furnace may be supported at the proper
height to render the oven readily accessible.
The cap of the outer casing and the top of the innermost casing have handles,
whereby said casings may be readily fitted into and out of position, and the inner
and second casings should be secured together, so as to form in effect one structure.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Saint John Vincent Day in the Great Seal Patent Office on the
14th April 1881.
SAINT JOHN VINCENT DAY, of Glasgow, in the County of Lanark, North
Britain, Civil Engineer. "IMPROVEMENTS IN APPARATUS FOR COOKING." A com-
munication from abroad by Daniel MacAlpin, of Philadelphin, in the State of
Pennsylvania, United States of America.
The object of the said Invention is to provide means for use with an ordinary
portable furnace, whereby the dissemination of odours due to cooking operations is
prevented, and the furnace is adapted for baking.
And in order that the said Invention may be properly understood I now proceed
more particularly to set forth the system, mode, or inanner, in or under which the
same is or may be used or practically carried into effect, reference being had to the
accompanying Drawings, and to the letters and figures marked thereon, that is to
say:-
Figure 1 is a vertical section of a portable furnace, with the improved detachable
oven applied thereto according to the said Invention; Figure 2 is a sectional plan on
the line 1, 2, Figure 1; and Figure 3 is a plan, and Figure 4 a perspective view of
details as hereinafter described.
A represents the casing, and B the fire pots of a portable furnace of the usual con-
struction, the said furnace having above the fire-pot a flue a communicating with
the stove-pipe, and having in the top plate the usual opening b, for the reception of
a culinary vessel. To this opening is fitted the lower end of a cylindrical casing D,
the upper end of which is closed by a suitable cap d, the lower end being open
to the flue a. To a flange e surrounding the upper edge of the fire-pot B is fitted
the lower end of an inner cylindrical casing E, open at its lower end to the fire,
and in the upper end of which is an opening f, communicating with the space
between itself and the outer casing, the casing E being concentric with, but some-
what less in diameter than, the casing D, so that when the two casings are applied
to the furnace, as shewn in Figure 1, the lower part of the said casing E, separating the
fire space from the flue a, the products of combustion are compelled to ascend the
chamber g, inclosed by the casing E, and then to descend the annular chamber i,
between the casings D and E, before they reach the flue a and the discharge pipe
or chimney. -
In the performance of culinary operations, such as boiling, frying, broiling, the
double casing D, E, is used for the purpose of carrying off to the chimney the
odours given off during the cooking operation, the utensil containing the food to be
cooked being inclosed by the inner casing, E, so that the odours are caused to
ascend with the products of combustion in the chamber g, and descend the annular
chamber i, escaping finally through the flue a and discharge pipe to the chimney.
When the apparatus is to be used for baking, however, the pans or receptacles con-
taining the dough are supported one above another by light frames m, and the
series of pans are inclosed by another innermost casing F, leaving an annular space
between its outerside and the innerside of the before mentioned inner casing E,
which I will now call the second casing. The lowest pan of the series (or the single
pan if but one be used) rests upon the flanged plate n, to which the lower end of
the innermost casing F is fitted.
A tile or slab p, of firebrick or other refractory material, intervenes between the
plate n and a plate 8, which is supported by feet resting upon an annular plate w,
the latter being also provided with feet w, which bear on the upper edge of the
fire-brick lining of the fire-pot B, the said feet supporting a disc plate y, between

page_text: the edge of which and the interior of the casing E the products of combustion pass,
thence passing by the opening in the plate w, into the chambers g and i, and thence
to the chimney, the outer and second casings D and E being applied, as shown in
Figure 1, so that the second casing E surrounds the innermost casing F, and the
supporting plates. The products of combustion in ascending the annular space
between the said casings E and F impart a high degree of heat to the said
casing F, and to the air contained therein before descending the annular chamber i
between the second and outer casings, and escaping to the chimney. The plates
n, w, and y, are shown in perspective in Figure 4.
The full effect of the fresh products of combustion is utilized in heating the
innermost casing F and its contents, there being very little loss of heat by radia-
tion, owing to the fact that the spent products of combustion, descending the
annular chamber i between the second and outer casings E and D, form an air-
jacket, and prevent the chilling of the inner casing F by direct contact of cold air
therewith.
The tile or slab p of refractory material prevents the imparting of such a high
degree of heat to the plate n as would cause the burning of the dough in the bottom
pan of the series.
The furnace has short feet y, which may be fitted into sockets in the upper ends
of the legs y¹ of the furnace or stove, whereby the furnace may be supported at
the proper height to render the oven readily accessible.
The cap d of the casing D and the top of the casing F have suitable handles d²,ƒ³,
whereby said casings may be readily lifted into and out of position, and the
casings D and E should be suitably secured together by bolts and distance pieces or
otherwise so as to form in effect one structure.
The top plate a³ of the stove is moveable, and can be lifted off and a ring with a
much larger opening substituted in a few seconds.
The casing D acts, as aforesaid, as a hot air jacket, and may be covered with
asbestos cloth, the wool side in and the wool felt (similar to skirt felt) on the out
side, which serves the double purpose of preventing it burning the hands when
using it and preventing the radiation of heat.
The cover d may be either made a permanent fixture or be secured so as to be
removable at pleasure, but for farmers who may wish to use the cooking apparatus
for cooking or baking all the year round, and occasionally in very cold weather to
enclose a large boiler to make hot feed to serve to their cattle, it will be well to make
the top removeable.
The inner casing F may be made as shewn in the Drawing, or it may be made in
sections, each section euclosing one and supporting the next pan.
The ovens can be made of any size to bake from a single loaf to the capacity of
a baker's oven; large ovens are raised with cords or chains passing over pulleys in
the ceiling, with counter balance weights (similar to a window sash) when desired
for convenience; the small ones also can be raised with a cord and weight passing
over a pulley.
There is no bread that can compare with that made by fermentation with yeast,
but in severely cold weather, without the necessary appliances, it has hitherto been
impossible to get it for domestic purposes. With one of these ovens and the heat
from the chimney of a coal-oil lamp (which, when required, gives light also)
fermentation can be carried on either night or day with a certainty and uniformity
at any temperature from 70 to 100 degrees that cannot be excelled.
Although I have represented a coal fire in the Drawing, yet it will be understood
that gas or other suitable fuel may be used to give the required heat, and it will
also be understood that where the innermost casing F is not used any suitable
means of supporting the food to be cooked may be employed. Although the stove
and casings are shewn of a circular figure, yet they may be of other convenient
shape in transverse section.
Having now described and particularly ascertained the nature of the said
Invention, and the system, mode, or manner in or under which the same is or may

page_text: be used or practically carried into effect, I would observe in conclusion, that what
I consider to be novel and original, and therefore claim as the Invention secured to
me by the herein before in part recited Letters Patent is,―
First. The combination with a furnace or stove having a top flue a, and
opening b, of the double casing D, E, arranged essentially as and for the purposes
herein before described with reference to the accompanying Drawings.
Second. The combination with the furnace and casings referred to in the
preceding claiming clause of the plate n, means for supporting the same within the
chamber g, and a casing F, adapted to the said plate n, and forming a baking
chamber, all essentially as herein before described with reference to the accompanying
Drawings.
Third. The use in combination with the matter claimed in the next preceding
claiming clause of a tile or slab p of refractory material, on which said plate n
rests, as and for the purpose hereinbefore described with reference to the accom-
panying Drawings.
In witness whereof, I, the said Saint John Vincent Day, have hereunto set my
band and seal, this Thirteenth day of April, in the year of our Lord One
thousand eight hundred and eighty one.