IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND FOR OTHER PURPOSES
Year: 1869

page_text: LETTERS PATENT to John Hill, of Wolverhampton, in the County
of Stafford, Ironfounder, for the Invention of "IMPROVEMENTS IN
FURNACES FOR STEAM BOILERS AND FOR OTHER PURPOSES."
Sealed the 19th November 1869, and dated the 12th June 1869.
PROVISIONAL SPECIFICATION left by the said John Hill at the Office
of the Commissioners of Patents, with his Petition, on the 12th
June 1869.
I, JOHN HILL, of Wolverhampton, in the County of Stafford, Iron-
founder, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND FOR OTHER PURPOSES,"
to be as follows:-
My Invention consists in constructing and arranging in the manner
herein-after described the parts of furnaces for steam boilers and for
other purposes, whereby the volatile or gaseous matters driven off from
the coal or other fuel are effectually and economically burned, and the
formation of smoke prevented.

page_text: I will describe my Invention as applied to a steam boiler furnace. I
make the bridge of the furnace hollow, the said bridge opening into a
chamber beneath it at the back of the ash-pit, the said chamber having
a door in front. Any dust or ash accumulating in the hollow
bridge and chamber may be removed by opening the said door. I make
the fire-bars hollow and open at both ends, the front ends being fixed in
holes in a dead plate at the front of the furnace, or being supported in
any other convenient support, and the rear or back ends of the said
hollow bars opening into the chamber in communication with the hollow
bridge. When the furnace is in work air passes through the hollow fire-
bars from the front of the furnace into the chamber beneath the hollow
bridge, and from thence through the said hollow bridge so as to mix with
the volatile combustible matter passing over the said bridge, which volatile
combustible matter coming in contact with the said air takes fire, and
burns without the formation of smoke. The air by its passage through
the hollow fire-bars becomes highly heated, and consequently effects the
combustion of the gaseous matter more effectually than cold air. The
said hollow bridge is open at top, and delivers the hot air in a thin sheet
or broad stream. In order to control the quantity of air passing. through
the hollow fire-bars to the bridge, a flap or damper may be fixed at the
front of the dead plate, by raising or lowering which flap or damper the
quantity of air entering the bridge may be regulated. The fire-bars may
be made of cast or wrought iron, and be either cylindrical in figure or
made of a tapering or wedge shape or other shape in cross section.
Although my Invention is especially applicable to furnaces for steam
boilers, yet my said Invention is also applicable to annealing and
puddling furnaces, and generally to all furnaces having bridges.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Hill in the Great Seal Patent Office on the
3rd December 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HILL, of Wolverhampton, in the County of Stafford, Ironfounder, send
greeting.
WHEREAS Her. most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of June, in the year of

page_text: our Lord One. thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Hill, Her special licence that
I, the said John Hill, my executors, administrators, and assigns, or such
others as I, the said John Hill, 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 FURNACES FOR STEAM BOILERS
AND FOR OTHER PURPOSES," upon the condition (amongst others) that I,
the said John Hill, 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 Hill, 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 consists in constructing and arranging in the manner
herein-after described the parts of furnaces for steam boilers. and for
other purposes, whereby the volatile or gaseous matters driven off from
the coal or other fuel are effectually and economically burned, and the
formation of smoke prevented.
I will describe my Invention as applied to a steam boiler furnace. I
make the bridge of the furnace hollow, the said bridge opening into a
chamber beneath it at the back of the ash-pit, the said chamber having a
door in front. Any dust or ash accumulating in the hollow bridge and
chamber may be removed by opening the said door. I make the fire-
bars hollow and open at both ends, the front ends being fixed in holes in
a dead plate or bearer at the front of the furnace, or being supported in
any other convenient support, and the rear or back ends of the said
hollow bars opening into the chamber in communication with the
hollow bridge. When the furnace is in work air passes through the
hollow fire-bars from the front of the furnace into the chamber beneath

page_text: the hollow bridge, and from thence through the said hollow bridge so as
to mix with the volatile combustible matter passing over the said
bridge, which volatile combustible matter coming in contact with the
said air takes fire, and burns without the formation of smoke. The air
by its passage through the hollow fire-bars becomes highly heated, and
consequently effects the combustion of the gaseous matter more
effectually than cold air. The said hollow bridge is open at top, and
delivers the hot air in a thin sheet or broad stream. In order to control
the quantity of air passing through the hollow fire-bars to the bridge,
a flap or damper may be fixed at the front of the dead plate, by raising
or lowering which flap or damper the quantity of air entering the
bridge may be regulated. The fire-bars may be made of cast or wrought
iron, and be either cylindrical in figure ar made of a tapering or wedge
shape or other shape in cross section.
Although my Invention is especially applicable to furnaces for steam
boilers, yet my said Invention is also applicable to annealing and
puddling furnaces, and generally to all furnaces having bridges.
Having explained the nature of my Invention, I will proceed to
describe, with reference to the accompanying Drawing, the manner in
which the same is to be performed.
Figure 1 represents in longitudinal vertical section, and Figure 2 in
horizontal section, a portion of a steam boiler the furnace of which is
constructed and arranged according to my Invention, and Figure 3 is a
transverse vertical section of the same taken through the line of
Figure 1; Figure 4 represents one of the bearers on a larger scale used
for connecting the fire-bars when two or more lengths are employed.
The same letters of reference are employed. to indicate the same parts in
each Figure.
a is the furnace or fire-place of the boiler, and 6 is the ash-pit, c is the
hollow bridge, and d is the chamber beneath the said hollow bridge,
e, e, are the hollow or tubular fire-bars of the furnace of a nearly wedge.
shape in cross section and open at both ends. The front ends of the
said fire-bars e are fixed in holes, in the bearer or dead plate fat the
front of the furnace a, and the rear or back ends of the said hollow
bars e are supported by the tubular bearer g, the said tubular bearer g
opening into the chamber d, in communication with the hollow bridge c.
The air when the furnace is in work, passes through the hollow fire-
bars e from the front of the furnace, and becomes heated thereby. The

page_text: said heated air on leaving the fire-bars enters the chamber d, and from
thence escapes through the hollow bridge c. The highly heated air thus
conveyed to the bridge passes out at the top of the said bridge by the
longitudinal opening c², in the form of a thin sheet or broad stream as
indicated by the arrows, and by mixing with the volatile combustible
matter passing over the said bridge effects the burning of the said
volatile matter without the formation of smoke. A flap or damper may
be fixed at the front of the bearer or dead plate f, for controlling the
quantity of air entering the bridge by the hollow fire-bars c. The front
of the chamber d is kept closed during the working of the furnace by
the door h (see Figure 1), hinged at 2, and connected with the said door
by the jointed rod i, is a platform or receiver k capable of turning on the
joint or centre k³. Upon this platform any dust or ash passing through
the hollow bridge c, accumulates. In order to remove the dust or ash
from the said platform the handle and rod connected with the door h
are pushed inwards. The bottom of the chamber d is thereby opened
by the falling back of the door h, and the platform k is made to take the
inclined position indicated in dotted lines in Figure 1. The dust or ash
on the said platform is thereby made to pass through the bottom of the
open chamber d into the ash-pit 6 from which it is removed in the
ordinary way.
Instead of making the hollow fire-bars e in one piece as represented,
they may he made in two or more pieces. In this case other bearers
of the kind represented in Figure 4 are used in the furnace in addition
to those represented in Figures 1, 2, and 3, into which additional
bearers the ends of the short hollow fire-bars are fitted, and by which
they are supported.
In applying my Invention to furnaces having bridges other than
steam boiler furnaces, I construct and arrange or combine the parts
substantially as herein-before described and illustrated in the accom-
panying Drawing, such changes only being made as are necessary to
fit them to the particular construction of furnace with which they are to
be used.
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 I
do not limit myself to the precise details herein described and
illustrated, as the same may be varied without departing from the nature
of my Invention; but I claim as my Invention the improvements in

page_text: furnaces for steam boilers and for other purposes herein-before described
and illustrated in the accompanying Drawing, that is to say, the con-
struction and arrangement or combination of the hollow or tubular
fire-bars, heated air receiving chamber, and hollow bridge, substantially as
described and illustrated for the purpose of effectually burning the
volatile or gaseous matter driven off from the coal or other fuel used, and
for preventing the formation of smoke.
In witness whereof, I, the said John Hill, have hereunto set my
hand and seal, this Thirtieth day of November, in the year of
our Lord One thousand eight hundred and sixty-nine.
Witness,
GEORGE SHAW.
JOHN HILL. (L.S.)