IMPROVEMENTS IN THE CONSTRUCTION OF KILNS FOR THE PURPOSE OF BURNING ARTICLES MADE, FROM PLASTIC MATERIALS
Year: 1868

page_text: LETTERS PATENT to John Holines, of Bradford, in the County of
York, Brick Manufacturer, for the Invention of "IMPROVEMENTS IN
THE CONSTRUCTION OF KILNS FOR THE PURPOSE OF BURNING ARTICLES MADE,
FROM PLASTIC MATERIALS."
Scaled the 4th June 1869, and dated the 5th December 1868..
PROVISIONAL SPECIFICATION left by the said John Holmes at the
Office of the Commissioners of Patents, with his Petition, on the
5th December 1868.
I, JOHN HOLMES, of Bradford, in the County of York, Brick Manu-.
facturer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF KILNS FOR THE PURPOSE OF BURNING.
ARTICLES MADE FROM PLASTIC MATERIALS," to be as follows:-
The purport of my Invention is to economize labour and fuel for the
purposes named in my title. For this purpose making my kiln of
circular formation (by preference) and placing a stack or chimney in the
centre of the same, I form a flue around the bottom of such stack or
chimney, such flue communicating by means of trap doors in its outer

page_text: wall with chambers radiating around the chimney. Each of these
chambers I furnish with a separate fire-place built in the wall, forming
the outer ring or wall of the kiln. Communications are made through
the whole series of chambers by means of trap doors in the upper and
lower portions of each partition wall. Vent holes (which may be closed
at will) in the roof of the kiln in cach compartment, admit the
cscape of the gases when fire is applied to "green" goods. Each
compartment is charged with goods by a temporary aperture made in
the outer wall of the kiln. Ordinary mechanical appliances are used
for raising the trap doors.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Holmes in the Great Scal Patent Office on.
the 5th June 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, JOHN
HOLMES, of Bradford, in the County of York, Brick Manufacturer, send.
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of December, in the year
of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John Holmes, Her special
licence that I, the said John Holmes, my executors,, administrators, and
assigns, or such others as I, the said John Holmes, my executors, ad-
ministrators, 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 THE CON-
STRUCTION OF KILNS FOR THE PURPOSE OF BURNING ARTICLES MADE FROM PLASTIC
MATERIALS," upon the condition (amongst others) that I, the said John
Holmes, 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

page_text: 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 Holmes, 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 thereof, that is to say:-
My Invention relates to circular kilns, the object of my said Invention
being so to construct such kilns as to facilitate the charging and firing
thereof, and thus economize labour and fuel, and to admit of the
compartments or chambers of the kiln being used either independently
of one another or continuously, as may be required.
According to my said Invention, the said kilns are constructed as
follows: An annular smoke chamber is built around the chimney in
the centre of the kiln, and communicates with the said chimney by
means of flues formed in the wall thereof. Permanent radial division
walls are built in the kiln, which walls extend from the smoke chamber
to the outer wall of the kiln, and divide it into firing compartments or
chambers, in which the goods to be fired are placed. Flues are made
in the said division walls to connect one chamber with another, and
other flues are made in the wall of the smoke chamber to connect it
with the firing chambers, the said flues being closed as required by
means of sliding dampers. Firing holes are formed in the outer wall
of the kiln, and other holes (provided with covers) are formed in the
top of the kiln for the purpose of allowing steam to escape during the
first stage of burning goods, and inserting fuel during the last stage of
burning. Openings or wickets (large enough to admit a horse and cart)
are made in the outer wall of the kiln one to each chamber, through
which openings the goods are taken into and out of the kiln. In using
the kiln, one of the firing chambers is filled with green goods to be
burnt, and the opening through which they were introduced is walled
up and cemented, two fire holes being left in the brickwork one above
the other. The said chamber is then fired at its lower firing holes, and
the flues in its radial walls are closed, the dampers in the wall of the
smoke chamber being opened to allow the smoke to pass to the chimney,
the holes in the top of the kiln being also opened to allow the steam
from the green goods to escape. As the firing goes on these latter
holes are closed, except when used for firing. During the firing of one
chamber or compartment the next is being filled with green goods;

page_text: when this has been done the flues in the wall separating the two
chambers are opened, and the flues leading from the chamber which
was first fired to the smoke chamber are closed, the smoke chamber
flues in the chamber containing the green goods being opened. The
gases of combustion and the warm air then pass from the first chamber
containing the burnt goods into the chamber containing the green goods,
which is now fired.. The several chambers of the kiln are fired in
rotation in thic manner described. Each of the firing chambers can be
worked independently of the other chambers, or any number of them
can be fired together, or by suitably working the dampers of the kiln
the heat can be made to pass through the whole series of chambers, so
that the kiln shall have what is termed a "continuous " action.
Having now described the nature of my Invention, I will proceed to
describe the manner in which the same is to be performed, reference
heing had to the accompanying Drawing and to the letters and figures
marked thereon, that is to say:-
Figure 1 is a side elevation of a kiln constructed according to my
Invention; Figure 2 is a vertical section of the said kilu; Figure 3 is a
horizontal section of the said kiln; and Figure 4 is a plan of the said
kilu; Figures 5 and 6 represent details herein-after referred to. The
same letters indicate the same parts in all the Figures.
A is the chimney of the kiln; B is the smoke chamber; C, C, are
radial partition walls, which divide the kiln into chambers or com-
partments D, D, and are furnished with flues E', E, and dampers E, E;
F is the wall which divides the smoke chamber from the chambers D, D,
which wall is furnished with flues G¹, G', and dampers G, G; H', H',
H2, H2, are two series of fire holes formed in the outer wall I of the
kiln, which fire holes are furnished with doors and grates; J, J, are
holes formed in the top of the kiln, through which the steam from the
green goods escapes, and fuel is afterwards fed; these holes are provided
with covers j, j. K, K, are port holes, through which the state of the
goods being fired can be ascertained; L, L, are openings or entrances
through which the goods are taken into and out of the kiln; these
entrances being large enough to admit a horse and cart, the labour of
carrying the goods in and out by hand is avoided; M, M, are holes
in the top of the smoke chamber to allow of the escape of air; m, m, are
the covers of the said holes. Figure 5 is a sectional elevation of part
of the kiln, showing the arrangement of flues and dampers in the smoke

page_text: chamber. Figure 6 is a section of part of one of the division walls C of
the kiln, showing the arrangement of one of the dampers therein, and
the means by which it is worked. E is the damper, which is connected
by wires or rods e¹, e, to a screw e, which works in a female screw
formed in the plate et, and is turned by a cross handle e in one or other
direction, so as to raise or lower the damper as required.
The action of the kiln is as follows:-One of the chambers D, D, is
filled with green goods, and the opening through which they were
introduced is walled up and cemented, fire holes similar to the holes
H', H, being left in the brickwork. The said chamber is then fired
at the lower fire holes H', H. The flues E¹ are closed and the flues G¹
are opened. The gascous products of combustion pass through and
heat the goods and pass into the smoke chamber B, and thence into
the chimney A. While the goods are being dried the holes J, J, are
kept open to allow the steam to escape, but when the said goods have
become heated, fuel is fed through the said holes which are then closed.
During the firing of the said chamber the next is filled with green
goods. When this has been done the flues E' in the wall which
separates the two chambers are opened, and those of the flues G¹ which
lead from the chamber first fired to the smoke chamber B arc closed,
and those of the flues G which lead from the chamber containing the
green goods to the smoke chamber are opened. The warm air from the
first chamber now passes into the next chamber containing the green
goods, which are thus dried, and this chamber is then fired. The
several chambers D, D, of the kiln are or may be fired in rotation in the
manner described. Each of the chambers D, D, may be worked inde-
pendently of the other chambers by keeping the flues E¹, E', closed,
and the flues G, G', open. Or any number of the said chambers may
be fired together, or the whole series of chambers may be worked
continuously by opening all the flues in the partition walls, except those
in the wall at the rear of the chamber which was first fired, and closing
all the flues leading to the smoke chamber, except those in the chamber
last fired.
By the novel construction of kilns constituting my Invention, a
considerable saving of fuel and labour is effected in the firing or burning
of bricks and other goods made from plastic materials.
Having now described the nature of my Invention and the manner
in which the same is to be performed, I wish it to be understood that

page_text: I do not claim any of the parts of my improved kiln as forming
separately and apart from their combination as described any part of
my said Invention; but I claim as my said Invention constructing
circular kilns with permanent radial walls or partitions, by which the
said kilns are divided into a series of heating chambers, such chambers
being fired, partly from fire holes in the outer wall of the kiln, and partly
from holes in the top of the said kiln, and being provided with flues and
dampers, by means of which arrangement the said chambers can be
worked either separately or continuously, as described.
In witness whereof, I, the said John Holmes, have hereunto set
my hand and seal, this Third day of June, in the year of our
Lord One thousand eight hundred and sixty-nine.