IMPROVEMENTS IN THE CONSTRUCTION OF FURNACES."
Year: 1863

page_text: LETTERS PATENT to Stephen Williamson, of Sheffield, in the County of
York, Engineer, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OF FURNACES."
PROVISIONAL SPECIFICATION left by the said Stephen Williamson at
the Office of the Commissioners of Patents, with his Petition, on the
28th February 1863.
1, STEPHEN WILLIAMSON, of Sheffield, in the County of York, Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
CONSTRUCTION OF FURNACES." to be as follows:-
My Invention applies to furnaces for steam boilers, furnaces used for the
conversion of iron into steel, and to every other kind of close furnace having
ta flue to carry away smoke or the products of combustion. The improvements
consist of an arrangement of perforated bricks and air passages, as hereafter
.described,, introduced into bridges beyond the grate bars, whereby combustion
is promoted and smoke, consumed, and in cases where applied to steam boilers
without the disadvantages which arise from bringing cold air in contact with
the hot surface of the boiler.
The mode of construction as applied to steam boiler furnaces is as follows:-
There is a bridge immediately beyond the grate bars built hollow, with an inlet

page_text: below the grate bars for the admission of air; this bridge has also two rows of
perforations, formed with bricks made for the purpose, on that side of the
bridge farthest from the fire for the escape of air intended to mingle with the
flame and smoke. At a short distance from the first bridge is a second
hollow bridge, hanging and built close up to the boiler bottom, with similar
perforations facing the former for giving out the air, which is supplied by pipes
on each side connecting the air chamber of the second bridge with that of
the first. The amount of air introduced is managed at pleasure by the
opening or closing of a door to the aperture beneath the grate bars; this door
is worked by an apparatus hereafter described. Beyond the second bridge
is a third bridge built solid; this serves the purpose only of conducting the
flame against the boiler bottom as soon as it leaves the second bridge. The
construction of other close furnaces for various purposes is carried out on the
same plan modified to suit the particular case.
The apparatus for opening and closing the air door is thus constructed:---
A small cylinder with a piston and rod is placed beneath the mouth plate of
the furnace; one end of the cylinder is open, the other is closed with a lid,
having a valve opening inwards to admit the air; and a tap to let it out at any
required rate. The piston rod projects through the lid, and the projecting part
is acted upon by a crank or tappet attached to the fire-door. When the piston
rod is pushed forward by the tappet, air enters the cylinder through the valve;
the other end of the piston rod moves the lever, which works a rod opening
the air door; as soon as the fire-doors are closed, the air which has entered
the cylinder is expelled at any required velocity through the regulating tap
by the air door acting on the rod lever.
SPECIFICATION
in pursuance of the conditions of the Letters Patent, filed
by the said Stephen Williamson in the Great Seal Patent Office on the
28th August 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1. STEPHEN
WILLIAMSON, of Sheffield, in the County of York, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of February, in the year of our
Lord One thousand eight hundred and sixty-three, in the twenty-sixth year
of Her reign, did, for Herself, Iler heirs and successors, give and grant

page_text: unto me, the said Stephen Williamson, Her special licence that I, the said
Stephen Williamson, my executors, administrators, and assigns, or such others
as I, the said Stephen Williamson, 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 "Ix.
PROVEMENTS IN THE CONSTRUCTION OF FURNACES," upon the condition (amongst
others) that I, the said Stephen Williamson, 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 Inven-
tion, 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 Stephen Williamson, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, reference being had to the Drawings hereunto annexed,
that is to say:-
My Invention applies to furnaces for steam boilers, furnaces used for the
conversion of iron into steel, and to every other kind of close furnace having
a flue to carry away smoke or the products of combustion. The improvements
consist of an arrangement of perforated bricks and air passages, as hereafter
described, introduced into bridges beyond the grate bars, whereby combustion
is promoted and smoke consumed (and in cases where applied to steam
boilers without the disadvantages which arise from bringing cold air in contact
with the hot surface of the boiler).
The mode of construction as applied to steam boiler furnaces is as follows:-
There is a bridge immediately beyond the grate bars built hollow, with an inlet
below the grate bars for the admission of air; this bridge has also two rows of
perforations (formed with bricks made for the purpose) on that side of the
bridge farthest from the fire for the escape of air intended to mingle with the
flame and smoke. At a short distance from the first bridge is a second
hollow bridge, hanging and built close up to the boiler bottom, with similar
perforations facing the former for giving out the air, which is supplied by
pipes on each side connecting the air chamber of the second bridge with that
of the first. The amount of air introduced is managed at pleasure by the
opening or closing of a door to the aperture beneath the grate bars; this door

page_text: is worked by an apparatus hereafter described. Beyond the second bridge is
a third bridge built solid; this serves the purpose only of conducting the
flame against the boiler bottom as soon as it leaves the second bridge.
Figure of the accompanying Drawings is a longitudinal section of a steam
boiler furnace constructed according to my Invention: Figure 2 is a plan of
the same with the boiler removed: Figures 3 and 4 are transverse sections
taken at the first and second bridges respectively. G is a bridge immediately
beyond the gråte bars H. built. hollow, and with an inlet I below the grate bars
for the admission of air; this bridge has also two rows of perforations J, J,
formed with bricks, by preference of the form shewn in Figure 5, on that
side which is farther from the fire for the escape of air to mingle with the
flame and smoke. K is a second hollow arched, bridge, built close up to the boiler
bottom, with perforations L, L, similar to and facing the perforations J, J, for
giving out the air, which is supplied by pipes M on each side connecting the
air chamber N of the bridge K with the air chamber of the bridge G.
The quantity of air introduced is regulated by the opening or closing of a door
to the aperture I, worked by apparatus hereafter described. P is a third
bridge built solid, which, as before stated, serves the purpose only of conducting
the flame against the boiler bottom as soon as it leaves the bridge K. The
red arrows in Figure indicate the course of the flame, and the blue arrows
the course of the air admitted at the bridges G and K. The construction of
other close furnaces for various purposes is carried out on the same plan
modified to suit the particular case. The apparatus for opening and closing
the air door is constructed as shewn in Figure 6. A small cylinder A, with a
piston and rod B, is placed beneath the mouth plate of the furnace; one end
of this cylinder is open, the other is closed with a lid, having a valve D opening
inwards to admit the air, and a tap on the pipe E to let it out at any required
rate. The piston rod projects through the lid, and the projecting part is acted
upon by a crank or tappet F attached to the fire-door. When the piston rod B
is pushed forward by the tappet, air enters the cylinder through the valve D;
the other end of the piston rod moves a lever C, which works a rod C¹, opening
the air door; as soon as the fire-doors are closed, the air which has entered the
cylinder is expelled at any required velocity through the regulating tap by the
air door acting on the rod lever in closing.
And having now described the nature of my said Invention, and in what
manner the same is to be performed. I declare that I claim as my "Improve-
ments in the Construction of Furnaces,"
First, the arrangement of perforated bricks, air chambers, and passages

page_text: introduced into bridges beyond the grate bars, substantially as herein-before
described and illustrated in the accompanying Drawings.
Second, the apparatus for regulating the admission of air below the grate
bars of furnaces, constructed and acting substantially as herein-before described
and illustrated in Figure 6 of the accompanying Drawings.
In witness whereof, I, the said Stephen Williamson, have hereunto set
my hand and seal, this Twenty-fifth day of August, One thousand
cight hundred and sixty-three.
Witnesses,
ALFRED APPLEBY.
WILLIAM CARSON.
STEPHEN
his mark. (L.S.)
WILLIAMSON.