IMPROVEMENTS IN KITUTO AND IN BURNING BRICKS AND SUCH LIKE ARTICLES
Year: 1873

page_text: LETTERS PATENT to William Frederick Beart, of Godmanchester, in
the County of Huntingdon, for the Invention of "IMPROVEMENTS IN
KITUTO AND IN BURNING BRICKS AND SUCH LIKE ARTICLES.”
"
PROVISIONAL SPECIFICATION left by the said William Frederick
Beart at the Office of the Commissioners of Patents, with his
Petition, on the 5th November 1878.
I, WILLIAM FREDERICK BEART, of Godmanchester, in the County of
Huntingdon, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN KILNS, AND IN BURNING BRICKS AND SUCH LIKE ARTICLES,"
to be as follows :-
This Invention has for its object improvements in kilns, and in
burning bricks and such like articles.
In the burning of bricks a great economy of fuel is effected by the
use of the kiln known as the Hoffmann kiln. In this kiln the fuel is
dropped down amongst the bricks through holes in the roof or arch, and
the heat resulting from its burning is passed on from the compartments

page_text: of the kiln in which the burning is taking place into other compartments
in which green bricks are set. The air to support combustion also is
passed amongst the bricks which have been already burnt and is so
highly heated before it reaches the burning compartment.
Although such kilns succeed well where the clay is of an open nature
so that the moisture can freely escape from it great difficulty is
experienced in burning in such kilns the best description of bricks, such
as are made of ganet clay or clay of a close and dense nature. The high
and moist heat to which the green bricks are exposed causes them to
break and crack; and besides, even when the bricks are burnt sound the
color is not good. Now according to my Invention I obviate these
disadvantages whilst still obtaining much of the economy of the Hoffmann
kiln.
I operate in the following manner :-I construct the kiln in the same
way as the Hoffmann kiln is usually constructed so that it can be
divided into separate compartments by movable partitions and so that
fuel can be introduced by holes in the roof or arch; and in addition I
provide a small furnace or fire-hole for each compartment of the kiln; it
is formed beneath the floor of the compartment, from side to side of which
the fire-bars extend. The heat issues by holes formed in the floor.
When the green goods have been set a small fire is lighted in the
furnace or fire-hole of the compartment, and the goods are gradually
dried and "tanned" for several days, during which time the door of the
furnace or fire-hole may be kept open to allow air to enter freely, and it
is not till this drying and tanning process is complete that the waste
heat from the burning is allowed to come upon the goods.
The drying and tanning being complete the furnace or fire-hole of the
compartment is bricked up, and the partition which separates the com-
partment from the part of the kiln where the burning is going on is
removed, and then the further heating and burning of the bricks or other
articles is accomplished as in the Hoffmann kiln.
At the end of the burning process I sometimes renew the fire in the
furnace or fire-hole with the object of improving the color of the goods.
These fire-holes or furnaces are also of great use in starting the kiln. At
the present time great inconvenience results when the Hoffmann kiln ;
cannot be kept regularly supplied with goods. If the kiln is let out

page_text: there is much trouble in again starting it, whereas my improved kiln
can be let out whenever desired without inconvenience or much waste
of fuel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Frederick Beart, in the Great Seal Patent
Office on the 5th May 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
FREDERICK BEART, of Godmanchester, in the County of Huntingdon,
send greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Fifth day of November, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Frederick Beart, Her
special license that I, the said William Frederick Beart, executors,
administrators, and assigns, or such others as I, the said William
Frederick Beart, 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 KILNS, AND IN BURNING BRICKS AND SUCH LIKE ARTICLES,"
upon the condition (amongst others) that I, the said William Frederick
Beart, my executors or administrators, by an instrument in 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 William Frederick Beart, 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 :-
In burning bricks and other such like articles fuel is economised by
using kilns such as are known as "Hoffman" kilns. In these kilns

page_text: the heat escaping from the part of the kiln where fuel is being burnt
and where the bricks are most highly heated is carried on and caused to
partially burn other bricks before it escapes into the flues.
Now the objects of my Invention are whilst obtaining much of the
economy of the ordinary Hoffmann kiln to burn bricks of the best
quality made from dense close clay without causing them to crack,
warp, or become unsound, and without spoiling their color. In order to
burn such bricks sound, in place of turning the high and
the kiln on to them when in a green state I first “tan or slowly dry
them by gentle fires. Afterwards they may safely be exposed to the
heat from the burning compartments of the kiln.
"
moist heat of
In order to preserve the color of the bricks it is necessary to expose
them to the action of flame after the highest temperature of burning has
been attained, and this I do by means of the same fires which I employ
to "tan" the bricks.
In the annexed Drawings I show a plan in section and an horizontal
section of a portion of a Hoffman kiln having combined with it firc-
places extending across beneath the bottom or floor.
a, a, are the main walls and arched roof of the kiln; a', a', the holes
called "potholes" in the roof for throwing down small coal amongst
the bricks (or other articles) which are being burnt; b is the main flue
of the kiln leading to the chimney c; d, d, are the branch flues leading
to the different compartments of the kiln, and each provided with a
valve & which can be opened or closed; e, e, are grooves in the main
walls which receive the movable "portcullis " by which the body of the
kiln is separated into a series of chambers. These parts are all arranged
as is usual in Hoffman kilns. Or in place of the portcullis partitions
permanent partitions of brickwork with passages in them at both top
and bottom which can be opened or closed by slides may be used. ƒ,ƒ,
are the cross walls beneath the floor of the kiln to form the fire-places ; into
these walls bearing bars f¹, f, are built, and these support fire-bars ƒ³,ƒ³;
arches f³, ƒ³, are built over to enclose the fire-places, and these have
spaces between them for the escape of the flame and products of com-
bustion into the kiln; over the arches a level floor of fire-brick is laid
leaving numerous openings ff, for the fire to ascend into the kiln ;
the front of each fire-place can be closed by doors fitted both over and
under the fire-bars so that these fire-places can be closed up at pleasure

page_text: in such a way that little or no air can enter by this route into the kiln.
A little moist clay may be used in order more effectually to exclude air.
g is one of the fire-doors, it is cast with projections upon it to receive
clay so that it may not become excessively heated; h, h, are stoke holes
excavated beneath the ground line.
In working the kiln after the green bricks have been set in one of the
chambers fires are lighted in the fire-places of this chamber, whilst it is
divided off from the chambers where the burning is going on. Small
slow fires are kept up for two or three days and so the bricks are slowly
dried and warmed. Then the chamber is opened to the adjacent chamber
so that the heat of the kiln may pass through it on its way to the
chimney; this continues until the bricks are red hot and then small coal
is introduced as usual by the holes a¹ until the full heat required is
obtained; meanwhile the heat from this compartment is carried on to
other compartments containing "tanned" bricks. When the burning is
complete, or nearly so, the fires are made up again in the fire-places of
the chamber and they are urged so as to produce a flame which plays over
the hot bricks and whitens them. At this time I prefer that the com-
munication with the next chamber containing bricks which have been
already burnt and whitened should be closed, as the bricks will not be
thoroughly whitened if the draft from the cooling bricks be allowed to
pass amongst them. This it is true involves some waste of heat, but the
improved quality more then compensates for this loss, or the loss may
be avoided by providing the kiln with other flues by which hot air from
any compartment may be led away to drying floors and utilized in
preparing the bricks for the kiln.
In place of introducing small coal by "pot holes" at the top all the
fuel necessary for burning the bricks may be burnt on the fire-places
beneath the floor of the kiln, but this would increase the expense, as
small coal will not burn well on the fire-grates.
In straight kilns where access can be had to both sides there may be
fire-doors on both sides and the fires may be separated in the middle, the
fires still being within the main walls of the kiln.
Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood that what I
claim is, the combination with kilns such as are known as Hoffman's
kilns, or kilns in which the heat is brought forward, as herein described,

page_text: of fire-places within the kiln and extending across the floor of the kiln,
substantially as described.
I also claim the process of burning bricks or other articles in a kiln
such as is known as Hoffman's kiln so as to preserve the color by the
successive operations of submitting the bricks or other articles to the
heat brought forward from other compartments of the kiln, then to the
further heat developed by the combustion of fuel dropt amongst them
from the top of the kiln, and finally to the action of flame from a
separate fire provided at the bottom of the kiln, substantially as
described.
In witness whereof, I, the said William Frederick Beart, have
hereunto set my hand and seal, this Fourth day of May, in the
year of our Lord One thousand eight hundred and seventy-four.