IMPROVEMENTS IN KILNS FOR BORNING BRICKS. LIME. AND ARTICLES OF EARTHENWARE
Year: 1869

page_text: LETTERS PATENT to Jonathan Mitchell, of Bradford, in the County
of Yorkshire, Bricklayer, for the Invention of "IMPROVEMENTS IN
KILNS FOR BORNING BRICKS. LIME. AND ARTICLES OF EARTHENWARE."
"
Sealed the 8th February 1870, and dated the 16th August 1869.
PROVISIONAL SPECIFICATION left by the said Jonathan Mitchell at
the Office of the Commissioners of Patents, with his Petition, on
the 16th August 1869.
I, JONATHAN MITCHELL, of Bradford, in the County of Yorkshire,
Bricklayer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN KILNS FOR BURNING BRICKS, LIME, AND ARTICLES OF EARTHEN-
WARE," to be as follows:-
My improvements are applicable to arched kilns, and consist in a
new arrangement of flues and dampers.
In performing my Invention I make use of any convenient number
of fire-places, which may be set at equal distances along both sides of
the kiln. Between the fire-places are made dampers connected to flues
running on the outside of the kiln. I use a number of chambers in
my improved kiln, and when ready to commence burning bricks or

page_text: other articles I prefer to fill three of the chambers with the articles to be
burnt, and to make fires in the two fire-places of the first chamber, two
fire-places being provided in each chamber. At the opposite end of the
chamber to the fire-places are dampers to open and close passages leading
from the chambers to the outside flues, which flues are connected to the
chimney. The two end chambers of the kiln are connected together by a
flue running under the kiln for the purpose of conveying the fire and
heat which may have been used in the last chambers to burn fresh bricks
in the first chambers. By this system of fire-places and dampers I am
able to utilize all the heat from the furnace in a continuous manner.
Another part of my Invention consists in an arrangement of passages
and flues at the lower part of the kiln for the purpose of partially
drying green bricks. In performing this part of my Invention I
propose to make two passages the whole length of the kiln with tram-
ways in them, on which tramways are trucks; these tramways may be
connected by turntables with side lines for the purpose of conveying
the bricks into the drying chambers and also to the kiln for stacking;
these trucks may stand in the passages as long as desired. In some
cases I use separate fires with flus under these drying chambers.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Jonathan Mitchell in the Great Seal Patent Office
on the 16th February 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JONATHAN
MITCHELL, of Bradford, in the County of York, Bricklayer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of August, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Jonathan Mitchell, Her special license
that I, the said Jonathan Mitchell, my executors, administrators, and
assigns, or such others as I, the said Jonathan Mitchell, my executors,
administrators, or 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

page_text: vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
KILNS FOR BURNING BRICKS, LIME, AND ARTICLES OF EARTHENWARE," upon.
the condition (amongst others) that I, the said Jonathan Mitchell,
my executors or administrators, by an instrument in writing under my
hand and seal, 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 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 Jonathan Mitchell, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:
My said Invention relates to arched kilns, and consists in a new
combination and arrangement of the flues and dampers thereof.
In carrying out my Invention I employ any convenient number of
fire-places, which may be set at equal distances along both sides of the
kilns. Between the fire-places dampers are provided connected to flues
running on the outside of the kiln. I use a number of chambers in
my improved kiln, and when ready to commence burning bricks or
other articles I prefer to fill three of the chambers with the articles
to be burnt, and to make fires in the two fire-places of the first chamber,
two fire-places being provided in each chamber. At the opposite end
of the chambers to the fire-places are dampers to open and close passages
leading from the chambers to the outside flues, which flues are connected
to the chimney. The two end chambers of the kiln are connected
together by a flue running under the kiln for the purpose of conveying
the heat which may have been used in the last chambers to burn fresh
bricks in the first chambers. By this system of fire-places and dampers
I am able to utilize all the heat in a continuous manner.
And in order that my said Invention may be fully understood, I shall
now proceed more particularly to describe the same, and for that purpose
shall refer to the several Figures on the annexed Sheet of Drawings,
the same letters of reference indicating corresponding parts in all the
Figures.

page_text: Figure 1 of my Drawings represents a longitudinal section of my
improved kiln taken along the line 1-2, (Figures 3, 4, and 5) so as
to show the hot air flues which are built inside the side walls of
the kiln Figure 2 is a longitudinal vertical section taken along the
line 3-4, (Figures 3 and 4) shewing the several chambers, and the
central return flue which connects the first and last of the series of
chambers; Figure 3 is a horizontal section, one-half being taken along.
the line 5-6, (Figure 5) so as to shew the hot air flues, and the other
half along the lines 7-8, (Figure 5); Figure 4 is a transverse vertical
section taken along the line 9-10, (Figures 1, 2, and 3) shewing the
passages communicating with the external chimney flues; and Figure 5
is a similar view taken along the line 11-12, shewing the hot air flues.
A, A, are the external walls of the kiln, which may be of any desired
length; it is provided with an arched roof B and is sub-divided by
permanent division walls C, C, into any convenient number of chambers
(in my Drawings I have shewn six chambers numbered respectively
from 1 to 6); each chamber is provided with two fire-places a, a, one
on each side, and openings b, b, are made in the division walls for
enabling the heat and products of combustion to pass freely from one
chamber to another. These openings are provided with dampers c, c,
worked by weights and pullies from the outside of the top of the kiln
for the purpose of opening or closing the communication as required.
D, D, are lateral descending flues, two of which lead from each chamber
and carry off the smoke or vapour into the two external chimney
flues E, E, communicating directly with the chimney F. The flues D
are each provided with dampers d, d, worked from the outside, as
shewn in Figure 4, or otherwise. G, G, are lateral hot-air flues, two
of which lead from each chamber into the main hot-air flues H, H, and
also into the external chimney flues E, E, running longitudinally along
the side walls A, which flues pass forward the heat to any other
chamber, in order to dry the green bricks stacked ready for being burnt,
or to cool down the bricks in the chambers after being burnt. Any
of the chambers may be thus brought into communication through the
hot-air flues by opening the hot-air dampers e, e, provided for that
purpose and worked from the outside, as shewn in Figure 5, or other-
wise. I is a central return flue for conveying the whole or a portion of
the heat back from the last to the first chamber of the series, as shewn
by the arrows. K, K, are the side entrances to each chamber, and L, L,

page_text: are the firing holes in the roof, through which fuel in a fine state of
division is introduced into and amongst the bricks or other articles
or substances whilst being burnt. When the bricks are stacked ready
for burning in Number One chamber it is fired, and two, three, or four
dampers, as the case may be, are open so as to communicate with the
outside chimney flues to carry off the smoke and vapour, and when these
are got rid of I close these dampers again and open the two dampers c, c,
in the division wall communicating with Number Two chamber; I then
open the dampers d, d, and f, f, in this chamber, making a com-
munication thereby with the main chimney flues E, E, and close the
dampers d, e, and f in Number One chamber. When Number One
chamber is burnt off I close the two dampers c, c, in the division wall
and open the two dampers e, e, communicating with the hot-air flues
above to cool down the bricks, and pass the heat forward into another
chamber wherein are green bricks stacked for burning, and so on
alternately.
By my system of flues and dampers the heat is so beneficially applied
that it will burn off the six chambers in a week.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
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 hercin-before in part recited Letters Patent is, the combination
of the central return flue I, the hot-air flues G, H, and their dampers e
and f, the descending flues D with their dampers d, the outside chimney
flues E, and the openings 6 with their dampers c between each two
adjoining chambers of the kiln, the whole being arranged and worked
as and for the purpose herein-before described and illustrated by my
.Drawings.
In witness whereof, I, the said Jonathon Mitchell, have to this
my Specification, set my hand and seal, the Twelfth day of
February One thousand eight hundred and seventy.
JONATHAN MITCHELL. (L.S.)