IMPROVEMENTS IN FURNACES AND FIRE-PLACES
Year: 1854

page_text: LETTERS PATENT to Thomas Weatherburn Dodds, of the Holmes Engine
and Railway Works, Rotherham, in the County of York, Engineer,
for the Invention of "IMPROVEMENTS IN FURNACES AND FIRE-PLACES, FOR
PROVISIONAL SPECIFICATION left by the said Thomas Weatherburn
Dodds at the Office of the Commissioners of Patents, with his Petition,
on the 24th April 1854:
I, THOMAS WEATHERBURN DODDS, of the Holmes Engine and Railway
Works, Rotherham, in the County of York, Engineer, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN FURNACES AND FIRE-PLACES,
FOR EFFECTING A MORE PERFECT COMBUSTION OF FUEL AND PREVENTION OF SMOKE,"
to be as follows:-.
This Invention relates to a peculiar construction of furnace or fire-place for
steam boilers or other purposes, whereby a more perfect combustion of fuel
with the prevention of smoke is effected, and consists in the employment of a
series of hollow bars, through which the water of the boiler (when the furnace
is applied to a steam generator or water. heater) is allowed to circulate. The
smoke or bituminous vapour of the green fuel is caused to pass through the
fuel that has been previously coked, and which is pushed forward on to the
auxiliary bars, herein-before described. Or a separate door may be employed
for feeding the auxiliary bars with coke. By this means the coked fuel takes
up, for the supporting of its combustion, the smoke and unconsumed gases
evolved from the newly supplied fuel, at the same time that a certain amount
of atmospheric air is admitted at the, front, sides, top, through .or behind the

page_text: bridge of the furnace. The "auxiliary" bars may be connected to boilers or
steam generators of any shape and form, and may either constitute a portion
of the boiler, being attached thereto, or may be simply for heating water or for
feeding. The furnace above described is applicable also to puddling furnaces
and reverberatory furnaces, and to the heating of water for warming
buildings, conservatories, &c., and may be modified to suit almost any position,
whether for land or marine boilers, or for locomotive engine boilers. The
auxiliary bars may be laid either level, at an angle, or vertical; if the latter,
the fuel may be placed between two sets of bars, the furnace being fed from
above. In locomotive engine boilers the principles herein-before described may
be carried out by placing a furnace at each end of the boiler. In the front or
smoke box furnace it is proposed to burn coal, the smoke and unconsumed
gases passing along an internal flue or flues running part of or the entire length
of the barrel of the boiler, and opening into the ash pit of the second furnace,
the auxiliary" bars of which are made hollow, with the water of the boiler
circulating through them. The fuel employed in this furnace is coke, and the
smoke and unconsumed gases from the coal furnace pass through the burning
coke, and become consumed thereby. A second flue or series of flues conducts
the heat back again along the barrel of the boiler into the smoke box. By
another arrangement the two furnaces may be contained in one fire box, the
auxiliary bars, supplied with coke from a separate. door, being placed above
the bars containing the coal, so that the whole of the products of combustion
of the coal must pass through the burning coke. A third arrangement consists
in placing the auxiliary bars at an angle, with one end resting in a water space
division piece, running transversely across the fire box. This division piece
serves to direct the products of combustion from the coals burnt in the lower
grate down through the auxiliary bars, and burning coke into the flue or flues
of the boiler, which are situated beneath them. In order to keep up the
circulation in the auxiliary bars, a water pipe or pipes may be employed, in
some cases, connected with another portion of the boiler. In puddling or other
furnaces, when applicable, air passages through vessels containing water may
-be-employed for heating the air to feed the furnace above the bars, by allowing
a natural current of air to pass through them. Auxiliary bars may be used
in all furnaces, whether for engines, puddling reverberatory furnaces, or other-
wise. By another arrangement, a coke oven, ovens, or retorts may be employed
for the purposes of partially coking the coal before being pushed forward on to
the bars; (during the coking the bituminous vapour passes over the bars,) and
is taken up in combustion by the better coked part of the same; recesses are
made for heating the air before it is admitted into the furnace.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Weatherburn Dodds in the Great Seal Patent Office
on the 24th October 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WEATHERBURN DODDS, of the Holmes Engine and Railway Works, Rotherham,
in the County of York, Engineer, send greeting.
او ...
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of April, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Weatherburn Dodds, Her special license that I, the said
Thomas Weatherburn Dodds, my executors, administrators," and assigns,
or such others as I, the said Thomas Weatherburn Dodds, 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 vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for "IMPROVEMENTS IN FURNACES AND FIRE-PLACES, FOR
EFFECTING A MORE PERFECT COMBUSTION OF FUEL AND PREVENTION OF SMOKE," upon
the condition (amongst others) that I, the said Thomas Weatherburn Dodds,
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 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 Thomas Weatherburn Dodds, 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 a peculiar construction of furnace or fire-place
for steam boilers or other purposes, whereby a more perfect combustion of fuel
with the prevention. of smoke is effected, and consists in the employment of a
series of hollow auxiliary bars, through which the water of the boiler, when
the furnace is applied to a steam generator or water heater, is allowed to
circulate. The smoke or bituminous vapour of the green fuel is caused to pass
through through the fuel that has been previously coked, and which is pushed
forward on to the auxiliary bars herein-before described; or a separate door: may

page_text: be employed for feeding the auxiliary bars with coke. By this means the coked
fuel takes up, for the supporting of its combustion, the smoke and unconsumed
gases evolved from the newly supplied fuel, at the same time that a. certain
amount of atmospheric air is admitted at the front, sides, and top, and through
or behind the bridge of the furnace. The "auxiliary" bars or furnace may be
connected to boilers or steam generators of any shape and form, and may either
constitute a portion of the boiler, being attached thereto, or may be simply for
heating water or for feeding. The furnace above described is applicable also
to puddling furnaces and reverberatory furnaces, and to the heating of water
for warming buildings, conservatories, &c., and may be modified to suit almost
any position, whether for land or marine boilers, or for locomotive engine
boilers; the auxiliary bars may be laid either level, at an angle, or vertical. In
locomotive engine boilers the principles herein-before described may be carried
out by placing a furnace at each end of the boiler. In the front or smoke
box furnace it is proposed to burn coal, the smoke and unconsumed gases
passing along an internal flue or flues running part of or the entire length of
the barrel of the boiler, and opening into the ash pit of the second furnace, the
"auxiliary" bars of which are made hollow, with the water of the boiler circu-
lating through them. The fuel employed in this furnace is coke, and the smoke
& unconsumed gases from the coal furnace pass through the burning coke, and
become consumed thereby; second flue or series of flues conducts the heat
back again along the barrel of the boiler into the smoke box. By another
arrangement the two furnaces may be contained in one fire box, the auxiliary
bars, supplied with coke from a separate door, being placed above the bars con-
taining the coal, so that the whole of the products of combustion of the coal
must pass through the burning coke. A third arrangement consists in placing
the auxiliary bars at an angle, with one end resting in a water space division
piece running transversely across the fire box. This division piece serves to
direct the products of combustion from the coals burnt in the lower grate down
through the auxiliary bars, and burning coke into the flue or flues of the boiler,
which are situated beneath them. In order to keep up the circulation in the
auxiliary bars, a water pipe or water pipes may be employed-in some cases,
connected with another portion of the boiler. In these last-described arrange-
ments only one set of bars are directly open to the atmosphere, the water bars
not being open to the atmosphere. In puddling or other furnaces, when
applicable, air passages through vessels containing water may be employed
for heating the air to feed the furnace above the bars, by allowing a natural
current of air to pass through them. Auxiliary bars may be used in all
furnaces, whether for engines, puddling, reverberatory furnaces, or otherwise.

page_text: By another arrangement, a coke oven, ovens, or retorts may be employed
for the purposes of partially coking the coal before being pushed forward on to
the bars; during the coking, the bituminous vapour passes over the bars, and
is taken up in combustion by the better coked part of the same; recesses
5 are made for heating the air before it is admitted into the furnace.
And in order that my said Invention may be more readily understood, I
shall now proceed to describe the several Figures on the Sheets of Drawings
hereunto annexed.
Fig. 1 on Sheet 1 of my Drawings represents an end or front elevation of
a cylindrical boiler with internal flue, with the fire door removed, fitted with
my apparatus for effecting a more perfect combustion of fuel and prevention
of smoke; and Fig. 2 on the same Sheet of Drawings is a corresponding
longitudinal vertical section of the same, taken through the centre line of the
boiler. The ordinary fire bars A are supported at their inner ends by the
transverse water space B, which communicates with the interior of the boiler
by the lateral passages C, C. Into the back of this water space are fitted a
series of hollow water bars D, D, which 1 term "auxiliary" bars."
This second grate, formed by the auxiliary bars, is not open directly to the
atmosphere however, the first grate alone being supplied with atmospheric
air direct. The "auxiliary "bars are placed at a slight angle from a horizontal
line, and are screwed at their upper ends into another water space E, which
opens into the boiler through the top of the fire box, as shewn more clearly
at Fig. 2. By this arrangement, it will be obvious that a constant circulation
of water will take place through the "auxiliary" bars, thereby materially
expediting the generation of steam.
The two ash pits F and G are separated by a partition, which is fitted with
a hinged door H; for the purpose of regulating the supply of air to the inner
ash pit, and to facilitate the cleaning or removal of the ashes from the same,
a number of air passages I are formed in the brickwork over the mouth of the
furnace, and the air for supplying the same enters, as shewn by the arrows,
through apertures in the furnace door, and passes through the passages I into
the furnace itself above the burning fuel on the front and auxiliary bars of the
grate. The fuel on the "auxiliary "bars has first been coked or baked on
the ordinary bars near the mouth of the furnace, and afterwards, when suffi-
ciently coked, it is pushed forward on to the inclined "auxiliary" bars to make
room for fresh green fuel to be supplied to the front portion of the grate. As the
entrances to the flues J are situated in the second ash pit beneath the auxiliary
bars, it follows, as a matter of course, that the whole of the smoke and
unconsumed gases evolved from the green fuel in the front portion of the

page_text: grate must of necessity pass over and through the incandescent mass on the
"auxiliary "bars, and become thereby thoroughly consumed before entering the
flues J of the boiler. For facilitating the cleaning of the water bars, the front of
the water space B is made to take off, by which means facility is also afforded
for repairing or removing any-of--the water bars in case of fracture. Fig. 3
on the same Sheet of Drawings represents a plan and horizontal section of the
furnace of a cylindrical boiler with external flues, fitted with coking ovens or
retorts, for coking the green fuel before entering the furnace; Fig. 4 is a
vertical longitudinal section of the furnace; and Fig. 5 is a front elevation
of the same, with the furnace doors removed from one side to shew the interior
of one of the coking ovens and furnace. On each side of the principal
entrance A to the furnace are formed two coking ovens B, B, made of fire
clay, fire stone, or other fire-resisting material, which open into the front end
of the furnace C at the sides. These ovens are filled with fresh or green fuel
through the hoppers C¹, fitted with sliding doors and inverted funnel-mouthed
passage C this fuel is allowed to coke or bake-previously to being pushed
forward into the incandescent fuel in the body of the furnace. A plentiful
supply of air is admitted by the apertures D, D, situated in the sides of the
coking ovens over the fire-place and through the bridge E. This bridge is
constructed to give a large heating surface to the air passages, which may be
made zig-zag in plan, as shewn in the detail, Fig. 6; or they may be made.
alternately in the header and stretcher courses of the brickwork, as shewn in
the detail, Fig. 7. A second bridge F is situated a short distance behind.
the first bridge, by which means the heat is more confined, and consequently
more economised, than when passing direct along the flues to the chimney.
The space between the bridges forms also a combustion chamber, wherein the
smoke and unconsumed gases are ignited and consumed.
Fig. 1 on Sheet 2 of my Drawings represents a front or end elevation
and half transverse section of an engine boiler with internal flues, shewing the
application of fire brick, fire stone, or fire clay to the dead plate and arch
thereof, for the purpose of ensuring a better coking. medium-for-the-freshly-
supplied fuel before being pushed forward into the grato bars. Fig. 2 is a
corresponding longitudinal section of the same, shewing also the mode of
admitting a current or currents of heated air between the brickwork of the
bridge and the casting which supports the same; and Fig. 3 is a plan of the
boiler, with a portion broken away to shew the internal arrangement of
the furnace. The improvements in this boiler consist in the application of a
covering A of fire brick or fire clay to the dead plate and arch, for the
pose of facilitating the coking of the fuel contained thereon, by affording a
pur-

page_text: better coking medium. Another improvement in this boiler consists in the
formation of air passages between the brickwork B of the bridge and the
casting C, such air passage or passages being supplied with hot air from
the ash pit D direct into which they open, close under the furnace bars E.
The furnace bars are arranged alternately in couples or pairs, two up and two
down, at the bridge, as shewn in the Drawing, for the purpose of varying the
thickness of the fire; a small door F is fitted at the back of the ash pit, to
enable any dust or ashes carried over the bridge into the combustion chamber
G to be removed therefrom.
Fig. 1 on Sheet 3 of my Drawings represents a longitudinal vertical
section of a locomotive boiler fitted with my improved apparatus, whereby
coal may be employed also as fuel in place of coke alone. Transversely across
the fire box is an inclined water space A, which rises up from the lower
portion of the back of the fire box to within a short distance of the front of
the same, a small space B being left to allow the smoke and gases evolved
from the coal in the grate C to pass into the upper portion of the. fire box,
and be brought in direct contact with the incandescent coke on the auxiliary
water bars D. These bars, which are not open to the atmosphere, are slightly
inclined, and are fitted at their lower ends into the upper portion of the water
space A, whilst their upper ends are fitted in to the upper portion of the back
of the fire box above the mouths of the tubes E, E. The auxiliary bars D
are supplied with coke through the upper fire door F, and the lower grate is
supplied with coal through the bottom fire door G. H is a door for the
removal of the ashes from the ash pit I; J is the flame or combustion
chamber. Should it be found necessary to reduce the size of the combustion
chamber, the top of the barrel of the boiler may be elongated and the chimney
dropped through, as shewn by the dotted lines; any number of tubes or flues
E may be employed, from one upwards. The smoke and gases arising from
the coal fire ascend through the passage or opening B, and penetrate through
the incandescent coke on the "auxiliary" bars before entering the tubes
of the boiler, and are consequently consumed or ignited before reaching the
flame chamber end of the boiler. By the aid of the inclined water bars D, a
constant circulation of boiling water and formation of globules of steam is
kept up in the boiler, thereby tending to generate the steam more rapidly
than in the ordinary locomotive boilers. Fig. 2 on the same Sheet of
Drawings represents a sectional plan of the seating of a brewing copper,
shewing the arrangement of the flues and "auxiliary" water bars herein-before
described. A are the ordinary fire bars, and B the "auxiliary" or water bars,
which may be set at an angle, as' herein-before described. These bars, as I

page_text: have before described, are not open to the atmosphere, but receive their supply
of air from the first furnace A. The coal, having been well coked on the bars A,
is pushed forward on to the "auxiliary" bars, and the smoke and gases thrown
off from the partially consumed fuel on the bars A are made to penetrate
through the incandescent fuel on the water bars before it can enter the flues.
On leaving the furnace, the flame and heated air returns along the outside of
the same by the lateral return flues C, C, and then diverges right and left into
the circular flues D, D, the two currents uniting again at the back of the
furnace at E before entering the flue F; which leads direct to the chimney.
The water bars are connected at their extremities with the pipes G, H,
communicating with the tank I at different levels; thus, a constant &
continuous circulation.of hot water goes on through the water bars and along
the.. pipes G. and Hto the tank. In place. of. the ordinary fire bars A; a fire
brick coking oven. or ovens may be substituted; occupying the whole or a
portion of the space at present taken up by the fire bars. In this oven the
fuel is coked; ás herein-before described, and, tlien pushed forward on to the
"auxiliary or water bars. Fig. 3 on the same Sheet. of Drawings represents
a longitudinal. vertical section of a double-draught puddling furnace; with-my
smoke-preventing apparatus rattached: The furnace A is supplied with coal
through the. feciling aperture B. A series of air holes C, C, are formed in the
sides of the furnace, to aid tlie combustion in the grate A... Inimediately behind
the bridge D are situated the inclined "auxiliary" water bars E, which are
fitted at their extremities into the water pipes F and G. This auxiliary fur-
nace is supplied with coke through the aperture H, and the smoke and gases
from the fire grate A must of necessity pass through the incandescent fuel on
the auxiliary bars, and be there consumed before entering the main body I of
the furnace. In place of the auxiliary" furnace being composed of hollow
water bars, it may be composed, as shewn at Figs. 4 and 5, of boiler plates
A, and short tubes B, connecting the same, through which tubes the flame
and gases is allowed to pass. These tubes may either be parallel or tapered,
and of any transverse section. Although two fires-are-shewn-in-the-Drawing
of the puddling furnace, yet the water bars may be used alone with the first or
ordinary grate, if desired, or vice versa. I may here observe, that although I
have in all cases where auxiliary bars are employed described the smoke and
unconsumed gases as passing from the coal fire, through the incandescent
fuel on the second or auxiliary grate, yet I do not claim the absolute use of a
coke fire in conjunction with a coal fire for the prevention of smoke; neither
do I claim the use of two grates for that purpose, so long as both grates are
open to the direct action of the atmosphere.

page_text: 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 I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without devi-
ating from the principles or main features of my said Invention; but what I
consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is,-
First, the general arrangement and construction of apparatus for effecting
a more perfect combustion of fuel and prevention of smoke, whether applied
to steam boiler or other furnaces, or for the purposes of heating water generally,
as herein-before described.
Second, the application and use of hollow bars or water passages, having
water constantly circulating through them in auxiliary furnaces, wherein the
bituminous and carbonaceous vapour or unconsumed products of combustion
are made to pass through the incandescent fuel contained therein, and between
the auxiliary bars or water passages supporting such fuel.
Third, the herein-before described peculiar arrangement of coke ovens of
any convenient form, and the application of the same to furnaces of all kinds,
cither with or without auxiliary bars, for the purpose of coking the coal
before being pushed on to the grate.
Fourth, the application and use of fire brick, fire stone, or fire clay, for
the purpose of covering the surface of the dead plate and arch, to afford a
better coking medium, as herein-before described.
Fifth, the admission of a current or currents of air in front of the bridge
plate and behind the brickwork of the bridge; also at the mouth of the
furnace, over the top and through the sides of the same, as herein-before
described and illustrated in Sheet 2 of the Drawings.
In witness whereof, I, the said Thomas Weatherburn Dodds, hath here-
unto set my hand and seal, the Twenty-third day of October, One
thousand eight hundred and fifty-four.
T. W. DODDS. (L.S.)