AN IMPROVED COOKING APPARATUS. PRODUCING A SAVING OF FUEL AND TIME
Year: 1857

page_text: LETTERS PATENT to Joseph François Maire, of No. 36, Rue de l'Echiquier,
Paris, in the Empire of France, for the Invention of "AN IMPROVED
COOKING APPARATUS. PRODUCING A SAVING OF FUEL AND TIME."
PROVISIONAL SPECIFICATION left by the said Joseph François Maire:
at the Office of the Commissioners of Patents, with his Petition, on the
20th March 1857..
I, JOSEPH FRANÇOIS MAIRE, of No. 36, Rue de l'Echiquier, Paris, in the-
Empire of France, do hereby declare the nature of the said Invention for
"AN IMPROVED COOKING APPARATUS, PRODUCING A SAVING OF FUEL AND TIME," to be
as follows; and consists in placing the food or aliments to be prepared in a
proper cooking vessel, having a tight-fitting or "autoclave" digester lid
provided with a safety valve. The vessel being placed on the fire, is taken off
as soon as the safety valve rises at a pressure regulated beforehand. The
vessel is then placed in a heat-preserving case, having double sides & bottom,
the space between being filled with bad heat-conducting materials, such as
coal dust, wool, hair. A double lid similarly provided is used to cover the
case, so that the cooking vessel being thus inclosed, the heat is preserved;
and the cooking of aliments continues after the vessel is removed from the
fire.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph François Maire in the Great Seal Patent Office on
the 19th September 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPHI
FRANÇOIS MAIRE, of No. 36, Rue de l'Echiquier, Paris, in the Empire of
France, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of March, in the year of our
Lord One thousand eight hundred and fifty-seven, in the twentieth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Joseph François Maire, Her special licence that I, the said Joseph
François Maire, my executors, administrators, and assigns, or such others as
I, the said Joseph François Maire, 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
inake, use, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "AN IMPROVED
COOKING APPARATUS, PRODUCING A SAVING OF FUEL AND TIME," upon the condition
(amongst others) that I, the said Joseph François Maire, 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 Joseph François Maire, 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:-
My Invention consists in putting the food to be prepared for eating with
'water and suitable condiments in a cooking vessel of the digester kind. This
vessel being placed upon the fire, the temperature is raised as high as two
atmospheres pressure, or about 121 degrees centigrade, which is shown by a
suitable valve fitted on the lid of the vessel. At the moment the valve begins
to raise and the steam escapes, I take the vessel from the fire & put it in a
double wrapper case made of any suitable thin material, but I prefer using
pasteboard; this case is provided with a double bottom, and the space between
the double wrappers and bottoms is filled with any material bad conductor of
caloric, such as powdered charcoal, sawdust, woollen, cotton, hair of animals,

page_text: feathers, or any other like substance suitably prepared. The bad-conducting
material, either powdered, fibrous, or any other, is introduced into the empty
space, and compressed therein, so as to leave.the least possible interstices, then
a double top lid filled with the same bad-conducting material is placed over
the case, so that the cooking vessel is completely wrapped up over, under,
and around with materials that will not suffer the heat to escape, and that the
caloric that has been produced when the vessel was upon the.fire.is.concentrated
in that vessel tightly shut up, & the cooking of the aliment will.be completed
away from the fire.
This effect of coction and cooking can last during 5 or 6 hours, .and.even
more, according to the size of the vessel, the thickness of the stratum of the
material bad conductor of heat, and of the degree of conductiveness of the
said material. The out casing, which I prefer making in pasteboard, but:which
could be made in any other suitable material, can be placed itself in a wooden
or metal box, to be carried far-off with great easiness even in travelling in a
carriage or wagon.
In order to have my Invention better understood, I annex a Sheet of
Drawing to show the mode of enclosing the cooking. vessel in its casing.
2°
Fig. 1 shows a vertical section made in the middle of a cooking.metallic
vessel fitted in its casing; Fig. 2 is the plan of the same with the lid.of.the
casing taken away. The lid of the digester A. is made fast with three
keys c, c, c, seen full size, Fig. 5 &-7; the said-keys have a small bit i, .which
slides through a groove of the hole a, Fig. 5. This Fig. shows the upper flange
of the vessel A. When the lid B is laid upon the vessel, and the holes bored
through, their respective flanges are in the right position, the keys are inserted
in and turned half round, so that the bits i come at the position shewn, Fig. 5,
and the lid is held fast, and the vessel is in the condition of a digester, viz., it
is capable of keeping the steam raised as high as the sides can resist without
bursting. The lid B is provided with a valve v, kept down by a spring
pressed by the screwed button 6; the spring is of a stiffness capable of
balancing the inward pressure exerted by the steam on the valve v.
A ring
h inserted through the button b.is for the purpose of lifting the lid up.
The vessel A after receiving the food to be cooked is provided with its lid and
placed over the fire till the valve rises, when it is taken out and put into the
casing C, D, made as previously stated with pasteboard, and filled with a
material bad conductor of caloric, either wool, hair, feathers, &c., the said
material being maintained inside by a casing of cloth or stuff of any kind, and
a lid E filled with the same material is put upon the casing C, D, where the
cooking keeps going on till it is completed by the confined heat.

page_text: The Figs. 3 & 4 show the vertical section and plan of a similar apparatus,
the cooking vessel A of which is made of clay, or any pottery suited for
cooking purposes; the lid B is made fast by means of a rope or string c, c, c,
which passes through a, a. A ring i, i, made of soft material, such as felt,
cloth, india-rubber, is placed between the flanges of the vessel and its lid, to
make it steam-tight. The vessel, Fig. 1, may be provided with a similar fitting.
The earthen vessels cannot be provided with valves; then to know when
the heat is sufficient, some drops of water are poured over the lid, and if it
vaporates instantly with a slight noise the vessel is taken out to be placed in
its casing.
My Invention can be applied not only to the cooking of victuals, but also
to any industry where the coction of substances of any kind is required,
as well as the preserving of heat in liquids.
The nature of my Invention being now described, and in what manner the
same is to be performed, I would have it understood that I do not mean to
confine myself to the precise forms, dimensions, and arrangements shewn and
described, neither do I claim separately as my Invention any of the parts
described when applied for other purposes; but what I claim as my Invention
is, to complete the cooking of food or coction of any other substance by
placing a suitable cooking vessel or digester containing the food or other
substance after its removal from the fire into a double wrapper casing filled
with material bad conductor of calorie, as it is described & illustrated on the
annexed Drawings.
In witness whereof, I, the said Joseph François Maire, have hereunto
set my hand and seal, this 18th day of September, in the year of our
Lord 1857.
Signed and sealed in the presence of
L. D'AUBREVILLE, C.E.,
Rue de l'Echiquier, 36.
J. F. MAIRE. (L.S.)