AN IMPROVEMENT IN CERTAIN COOKING APPARATUS
Year: 1825

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, The
Honorable WILLIAM ERSKINE COCHRANE, of Regent Street, in the County of
Middlesex, send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing
date at Westminster, the Eighth day of November, One thousand eight
hundred and twenty-five, in the sixth year of His reign, did, for Himself, His
heirs and successors, give and grant, unto me, .the said William Erskine
Cochrane, His especial licence that I, the said William Erskine Cochrane,
my, exors, adñiors, and assigns, or such others as I, the said William Erskino.
Cochrane, my exors, admors, or assigns, should at any time agree with, and
no others, from time to time and at all times during the term of years
therein expressed, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "AN IMPROVEMENT IN CERTAIN COOKING APPARATUS;" in which
said Letters Patent is contained a proviso, obliging me, the, said William
Erskine Cochrane, by an instrument in writing, under my hand and seal,
particularly to, describe and ascertain the nature of my said Invention, and in
what manner the same is to be performed, and to cause the same to be inrolled
in His Majesty's High Court, of Chancery within six calendar months next
and immediately after, the date of the said recited Letters Patent, as in
and by the same, referenco, being thereunto had, will more fully and at
large.anncar

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Erskine Cochrane, do hereby declare the nature of my said Invention,
and in what manner the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof (that is to say):-
My improvement in certain cooking apparatus consists in applying tho
flamo of a lamp, or the flames of lamps, to the purpose of heating an oven
or roasting apparatus for baking or roasting meat or other articles of food.
The said oven or roasting apparatus is made of thin metal plate in a cylindrical
or oval or other suitable form, having a door at one end to open in order
to introduce into or take out of the oven or roaster the meat or other articles
intended to be cooked therein, but when the door is shut, the oven or roaster
is closed at all parts excepting only certain small apertures or openings to let
out the steam arising from the meat or other articles which are to be cooked
in the oven or roaster, and other apertures provided with regulators to admit
fresh air into the same, in such manner and in such quantity as the process of
roasting is found to require. The said oven or roaster is surrounded with and
included within an external case made of metal or of any other fit material,
"but so much larger than the oven or roaster as to leave a narrow space or
cavity.all round between the external surface of the oven or roaster and the
case within which it is contained, in order that the said space or cavity may
receive a current of flame, heated air, and smoke by which the oven or roaster
is to be heated; and a suitable passage or fluc or chimney is provided at the.
upper or highest part of the said space or cavity so as to convey the smoke.
and unconsumed air away from the same, in order to cause a continual
current of such flame, smoke, and heated air to pass through the said space
around the oven or roaster.
-'
And thus far the apparatus is similar to the ovens or roasting apparatus now.
in use, but instead of making a fire of coals or of wood or other fuel upon
a fire grate, and conveying the flame, smoke, and heated air from that fire into
the space around the oven or roaster in order to heat the same, my improve-
ment is to apply a lamp'or, lamps: beneath the same in such manner that the
flame or flames of such lamp or lamps shall give heat to the oven or roaster,
and that all the smoke and heated air proceeding from such lamp or lamps
shall pass into and occupy the space or cavity around the oven or roaster, so as
to heat the same on all sides except at the part occupied by the door thereof;
and the flame or flames of the said lamp or lamps which are applied beneath.
the said oven or roaster must be so enclosed within the external case which
surrounds the same as that all the smoke and heated air proceeding from the.

page_text: fame or flames of such lamp or lamps must of necessity enter into and pass
through the space around the oven or roaster in order to heat the same, and
suitable apertures or openings must be provided at or near the flame or flames
of the lamp or lamps, in order to admit fresh air in currents so directed as to
blow or strike directly upon such flame or flames, and thereby to excite a
complete combustion, and to heat such part of the said air as is not consumed
by that combustion; and the external case must be so formed as to prevent the
entrance of any other air except such as shall be directed upon and through
the flame or flames as aforesaid, in order to maintain and excite the combustion
thereof. For the more complete explanation of the manner of carrying into
effect my said improvements in certain cooking apparatus I have hereunto
annexed a Drawing, representing a portable oven or roasting apparatus which
is heated by a lamp, according to my said improvement.
Fig. 1 is a perspective view of the apparatus to shew the external form
thereof; Fig. 2 is a transverse section; and Fig. 3, a longitudinal section.
The same letters of reference are used to denote the same parts in all the
Figures. A, A, is the oven or roaster, made of thin metallic plate in a
cylindrical or oval form; B is the closed end thereof; and C, the door which
closes up the front end; a, a, the hinges; and b, the catch to fasten the door..
The meat which is to be roasted or cooked is placed in a dish at the lower
part of the oven or roaster; and shelves may be fixed within the oven at d, d,
or e, in order to support any other articles which are required to be cooked
at the same time. D, D, E, is the external case which surrounds the oven or
roaster, and is of a similar form thereto, but so much larger as to leave a
narrow space all round between the two, and also between the flat ends B
and E, Figure 3; a projecting rim or flange c is formed round the front end
of the oven so as to fit into and fill up the end of the external case D, D, in
order to enclose the space between the two, and the edge or margin of the
door C applies to and fits against that projecting rim c. F is the lamp, which
is placed beneath the oven or roaster in order to heat the same; G is an:
inverted cone, the base of which is joined to the external case D, D; and the
burner of the lamp is fitted to the lower part of the cone, so as that all tho
heated air and smoke which proceeds from the flame of the lamp shall be..
conveyed up through the cone into the space between the external case
D, D, E, and the oven or roaster A, A, B,. so as to heat the same; and H is.
the chimney or exit passage from the top of the external case, to convey.away
the smoke and heated air after it has passed through the space which
Surrounds the oven or roaster; i, Figure 3, is a small tube which, proceeds
from the end B of the oven or roaster at the upper part thereof, and

page_text: passes through the end E of the external case, the extreme end of the tube i
being open to allow the escape of the escape of the steam or vapour which
arises from the meat or other articles which are to be cooked. I, Figuro 1,
is a small turning regulator, which is fitted in the door C of the oven or
roaster, and has four holes to admit fresh air into the lower parts of the same,
in order to facilitate the roasting of the meat; and by turning the regulator
those holes can be partially or completely closed, so as to regulate or stop the
passage of air through them. The lamp F is of that kind which is called an
argand burner, with a cylindrical wick to produce a circular ring of flame,
which is supplied by two currents of fresh air, one passing withinside of that
ring of flame and the other on the outside thereof.
Fig. 4 is a section of the lamp on a larger scale than the other Figures.
,, is the reservoir for the oil, tallow, coca-nut oil, or dripping, or other
inflammable matter with which the combustion and flame of the lamp is
maintained. This reservoir is a shallow circular vessel with the burner
situated in the centre of it; k is a hole to introduce the oil or melted tallow
or dripping, with a screw stopper to close it up. The lamp F is suspended in
its place beneath the apparatus by means of two spring clips a, a, which rise up
from each side of the reservoir K, and have pins at their upper ends to enter
into holes made in small brackets, which are fastened to and project down
from the under side of the external case D; the force of the springs a, a, is
sufficient to keep the pins in their places, but by pulling the two knobs f,f,
apart, the springs may be bent outwards so much as to withdraw the pins from
the holes in the brackets, and then the lamp may be removed from the appa-
ratus in order to trim the wick. 7, Figs. 1 and 3, is a tube which is fixed
horizontally beneath the external case D, and is directed to the flame of the
lamp, so that being opened at the front end the flame may be seen through
that tube, in order to observe if it burns properly; but at other times the front
end of the tube g is closed by a stopper; h, h, and I, 1, Fig. 4, are the two
tubes which are fixed concentrically one within the other, leaving a space
between them to receive the cylindrical cotton wick of the lamp in the usual
manner of argand lamps; n is the cylindrical ferrule or short tube to which
the wick is attached, and which is fitted to the internal tube 7, 7, so as to slide
up and down thereupon, and a pin projects inwards from the said ferrule to
enter into a spiral groove which is formed around the outside of the tube 1, 1,
in such manner that when the ferrule is turned round it will be raised or
Iwered; m, n, is the turning tube, which is lodged in the space between the
two concentre tubes h, h, and 7, 1, and receives the cotton wick and its ferrule n
within it; a pin projects out from the outside of the said ferrule, and is

page_text: received into an upright slot or opening, which is cut out in one side of the
turning tube m, in order that it may turn the ferrule and the wick round;
o, o, is a ring, which is fixed upon the upper end of the turning tube m, m,
by means of three arms or radii p, p, which project outwards and serve as
handles to turn the tube m round, in order to adjust the height of the wick,
for the ferrule n being turned round at the same time as the tube m, the afore-
said pin and spiral groove will cause the ferrule n to move up or down, and
the cotton wick moving with it may thus be adjusted in height, so that the top
edge thereof will stand up out of the space between the two concentric tubes
h, h, and I, I, to a suitable height to cause the flame to burn properly. The
upper part or raised rim of the ring o, o, is adapted to fit into the lower orifice
of the cone G (which is fixed at the lower part of the enternal case D, D, of
the oven or roaster), so as to allow the ring o, o, to turn; but to prevent the
passage of air an annular space or aperture, g, g, Fig. 4, is left open between
the under side of the ring o, o, and the top edge of the turning tube m, m, in
order to admit a current of fresh air to the outside of the ring of flame,
and that aperture, being formed as is represented in Fig. 4, will concentrate
the current of air around the flame. The passage through the interior of the
tube 1, 1, is open for the admission of air into the interior of the ring of flame;
and is a small conical button of metal fixed on the top of a wire which
stands up in the centre of the tube 1, 1, and the button r occupies so much of
the opening of the tube 1, l, as to contract the passage thereof to a narrow
annular opening, which being formed as represented in the section Fig. 4 will
give a divergent direction to the current of air which passes through the
opening, so as to project it upon the flame. The said lamp may be supplied
with oil or other suitable inflammable liquids, or with tallow, or with the
collected fat or dripping which proceeds from meat in roasting. The oil or
other liquid which is contained in the large reservoir K has free passage
through suitable holes in the tube h, h, into the space between the two con-
centric tubes h, h, and I, 1, in which the wick is contained, and the wick is
always supplied or immersed in the liquid; when tallow, or dripping, or cocoa-
nut oil, or other similar substance is used, the same must be melted and
poured into the reservoir K through the opening k when in fluid state; when
the lamp is lighted the heat of the flame will communicate sufficient warmth
to the reservoir K to melt the tallow, cocoa-nut oil, or dripping, and keep the
same in such a fluid state as to flow into the space l, l, h, h, in which the wick
is contained. In order to light the lamp when the tallow, cocoa-nut oil, or
dripping contained in the reservoir is cold and stiff, a small quantity of fluid
oil must be poured in at an opening & into a small internal reservoir contained

page_text: within the large one K, and that fluid oil will pass through small holes at the
upper part of the tube h, h, so as to flow around the wick and keep up
the combustion, until such time as the tallow, cocoa-nut oil, or dripping shall
become fluid by the heat of the flame. The said internal reservoir is only a.
narrow space included between two small partitions, which extend from the
circumference of the reservoir K to the tube h, h, 'in the centre thereof; and
the said partitions are joined to the top or cover of the reservoir K, but do not
descend to touch the lower part or bottom thereof, so that the oil which is
poured into the internal reservoir at s must rest upon the tallow, cocoa-nut oil,
or dripping which is at the bottom of the principal reservoir, but when the
śame is melted the fluid oil in the internal reservoir will mix therewith. The
said portable oven or cooking apparatus is supported upon four legs L, which
may stand upon a table, but when it is used on board ship it may be suspected
from the ceiling by four chains hooked into eyes, which are fastened to the
upper part of the external case at t, t. M are the handles, by which the whole
apparatus may be lifted; N are two small cases to hold plates and dishes at
the outside of the external case D, D, of the apparatus, so that they will be
warmed by the heat thereof. Note.-The external case may if thought
desirable be covered over with wood' or with matting, or other non-conducting
covering, to prevent loss of heat by communication to the air. To make the
apparatus portable the legs L are moveable, and can be taken-off-by-with--
drawing four keys, two of which are shewn at v, Fig. 1 and 3. The two plato
warmers N can be unhooked by only lifting them up; the lamp can be removed
as before stated, and all the parts thus separated may be packed within the
oven or roaster, the shelves d, d, e, being drawn out and turned up edgeways
to make room. The oven or roaster A, A, B, may be withdrawn out of its
external case D; D, E; in order to remove any soot- which may lodge in the
space between them; and the dimensions of the said apparatus may be known
by measuring the Drawing according to the scale thereupon, but the
dimension and the form of the parts may be greatly varied at the discretion
of the workman who is to construct the same, without departing from the
nature of my improvement. The particular construction of the burner for
the lamp herein-before described may be varied, and any other suitable kind
of lamp may be used instead of an argand burner, if preferred. Fig. 5 is a
section of a burner for a gas lamp, which may be applied to my approved
apparatus instead of the lamp before described; h, h, and 1, l, are two
concentric tubes united together and leaving a space between them for the
gass, which is introduced into that space by a branched tube k, k; and the
gass issues through several small holes at the upper part of the
space between

page_text: the tubes h, h, and 1, l; these holes being arranged in a circle will form a ring
of flame like that of an argand burner; and in the same manner the currents
of fresh air are admitted beneath the ring o, o, to the outside of the flame,
and also around the central button r, to supply the inside of the flame and
produce the same effect, as herein-before described. The burner is supported
by screwing its screw p into the nozzle of a tube or gas pipe, through which
the supply of gas is conveyed, and which must have a cock in it to regulate
the rate of the eflux of the gas; this nozzle and pipe must be so fixed in and
beneath a table or bench as that the burner shall stand up to a sufficient
height therefrom, in order that when the portable oven or cooking apparatus
is placed with it four legs upon that table (so as to stand over the burner),
the ring o, o, thereof shall enter into the lower orifice of the cone G.
In witness whereof, I, the said William Erskine Cochrane, have here-
unto set my hand and seal, this Eighth day of May, in the year of
our Lord One thousand eight hundred and twenty-six.
WILLIAM ERSKINE (L.8.) COCHRANE.
AND BE IT REMEMBERED, that on the Eighth day of May, in the year
of our Lord 1826, the aforesaid William Erskine Cochrane came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Eighth day of May, in the year of our Lord One thousand
eight hundred and twenty-six.