IMPROVEMENTS IN CONSTRUCTING AND ARRANGING OVENS SUITABLE FOR BAKING BREAD
Year: 1858

page_text: Sealed the 25th March 1859, and dated the 19th October 1858.
PROVISIONAL SPECIFICATION left by the said John Grant at the
Office of the Commissioners of Patents, with his Petition, on the 19th
October 1858.
I, JOHN GRANT, of Hyde Park Street, in the County of Middlesex, Captain
late Royal Artillery, do hereby declare the nature of the Invention for
"IMPROVEMENTS IN CONSTRUCTING AND ARRANGING OVENS SUITABLE FOR BAKING
BREAD," to be as follows:-
This Invention has for its object improvements in constructing and arranging
ovens suitable for baking bread for military and other purposes. For this
purpose two furnaces are constructed, one opposite to the other, and the heat
from the furnaces passes into a chamber between the two furnaces, and in this
chamber are placed two, four, or a greater number of ovens, (but four is the
number which I prefer), and they are arranged in such a manner as to leave
spaces or passages between the ovens, and the end and top and bottom of the
chamber, and also between the ovens themselves, so that the products of
combustion from the furnaces in passing to the flue which leads from the top
of the chamber, come in contact with three of the sides and with the top and

page_text: bottom of each of the ovens. The ovens are constructed of wrought-iron
plate, and are furnished with a double door in front; they slide into their
places in the chamber, and rest on bars suitably placed, and they are also
furnished with flanges, and these are secured by bolts to the frames which
form the sides of the oven chamber. In order that the parts of the ovens
which the heat first strikes may not be thereby injured, I so arrange the
furnaces that the fire bars are some distance removed from the oven chamber,
and in the spaces so obtained I arrange boilers or kettles for heating water or
for cooking.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Graut in the Great Seal Patent Office on the 19th
April 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GRANT, of Hyde Park Street, in the County of Middlesex, Captain late Royal
Artillery, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of October, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Grant, Her special licence that I, the said John Grant,
my executors, administrators, and assigns, or such others as I, the said
John Grant, 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,
use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
IMPROVEMENTS IN CONSTRUCTING AND ARRANGING OVENS SUITABLE FOR BAKING
BREAD," upon the condition (amongst others) that I, the said John
Grant, 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 John Grant, do hereby declare
the nature of the said Invention, and in what manner the same is to be

page_text: performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
This Invention has for its object improvements in constructing and arranging
ovens suitable for baking bread for military and other purposes. For this
purpose two furnaces are constructed, one opposite to the other, and the heat
from these furnaces passes into a chamber between the two furnaces, and in this
chamber are placed two, four, or a greater number of ovens, (but four is the
number which I prefer,) and they are arranged in such a manner as to leave
spaces or passages between the ovens and the end and top and bottom of the
chamber, and also between the ovens themselves, so that the products of
combustion from the furnaces in passing to the flue which leads from the top
of the chamber, come in contact with three of the sides, and with the top and
bottom of each of the ovens. The ovens are constructed of wrought-iron
plate, and are furnished with a double door in front; they slide into their
places in the chamber, and rest on bars suitably placed, and they are also
furnished with flanges, and these are secured by bolts to the frames which
form the sides of the oven chamber. In order that the parts of the ovens
which the heat first strikes may not be thereby injured, I so arrange the
furnaces that the fire bars are some distance removed from the oven chamber,
and in the spaces so obtained I arrange boilers or kettles for heating water or
for cooking.
And in order that my said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the Drawings hereunto
annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a side view of ovens constructed and arranged in the manner
I prefer in carrying out my Invention; Figure 2 is a longitudinal section;
Figure 3 is a horizontal section taken at the line A, B, Figure 2; and Figure
4 is a transverse section taken at the line C, D, Figure 2, of the same.
A, A, are two furnaces, one at each end; an end view of one of these furnaces
is shewn at Figure 5; they consist of the following parts-a, a, are two side
walls of brickwork, lined interiorly with fire tile or other suitable material,
which are tied together by the binding bars b; c, c, are cast-iron plates which
form the top of one of the furnaces A, and serve as a hot plate to receive
boiling kettles; the top of the other furnace is formed by a close boiler c',
which is furnished with a cock for drawing off the water as required; into the
brickwork of the side walls a, a, of each of the furnaces are built two bars d and
e, on which the ends of the fire bars rest; the front bars d, d, also support the

page_text: door plates ff; under the fire bars of each of the furnaces is formed a sunk
stoke hole g. The heat from the furnaces passes into the chamber B, and the
flues from the furnaces as they enter the chamber are furnished with dampers
h, h, by means of which the draft of the furnaces may be regulated, as may be
required. The chamber B is built in brickwork; it is arched over at the top,
and open at the sides; into these openings are built the plates i, i, which carry
the oven doors, j: the ovens k, k, are of wrought iron, and fit into openings
in the plates i, and a small flange formed at the front of each oven is secured
to this plate by screws; 1, 1, are bars supported from the bottom of the
chamber B, and which serve to carry the backs of the ovens. It will be seen
that a space is left all round between the walls of the chamber B and the
ovens, and also between the ovens and the bottom and top of this chamber.
These spaces serve as flues, as do also the spaces m, m, between the ovens;
the bottom of the chamber B is inclined as is shewn, for the purpose of
causing an equal distribution of the heat in these flues. Through the top of
the chamber B is an opening n into the chimney above, and a soot door is
placed immediately above to facilitate the cleaning the flues between the ovens,
and for sweeping the chimney. To afford ready access to the side flues
openings o, o, are left in the sill plates p, p, and when the covers are removed
from these openings, a brush may readily be passed through these side flues;
2 is a damper for regulating the draft between the chamber B and the
chimney, r, are pipes passing from the ovens into the flues to allow the
escape of heat and vapour when necessary; they are furnished with valves
worked with handles from the exterior. It is evident that the number of
ovens in the chamber B may be increased if it be desired, but four is the
number I prefer.
In witness whereof, I, the said John Grant, have hereunto set my hand
and seal, this Nineteenth day of April, in the year of our Lord One
thousand eight hundred and fifty-nine.
Witness,
FRED. HARRIS.
JOHN GRANT. (L.S.)