IMPROVEMENTS IN FURNACES, FIRE-PLACES, AND STOVES
Year: 1874

page_text: LETTERS PATENT to Charles Edward Bainbridge, of Middleton-in-
Teesdale, in the County of Durham, Superintendent of Lead
Smelting Works, and William Pinkney, of Eggleston, in the
County of Durham, Engineer & Superintendent of Saw Mills,
for the Invention of "IMPROVEMENTS IN FURNACES, FIRE-PLACES, AND
STOVES."
Scaled the 14th August 1874, and dated the 17th June 1874.
PROVISIONAL SPECIFICATION left by the said Charles Edward Bain-
bridge and William Pinkney at the Office of the Commissioners
of Patents, with their Petition, on the 17th June 1874.
We, CHARLES EDWARD BAINBRIDGE, of Middleton-in-Teesdale, in
the County of Durham, Superintendent of Lead Smelting Works, and
WILLIAM PINKNEY, of Eggleston, in the County of Durham, Engineer
& Superintendent of Saw Mills, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN FURNACES, FIRE-PLACES, AND STOVES,"
to be as follows:-
Our Invention relates to metallurgical and other furnaces used for
manufacturing purposes, the furnaces of stationary, marine, and loco-

page_text: motive steam boilers, and to cooking and heating stoves and fire-places,
and consists in the arrangements herein-after described, whereby the air
used to support combustion is heated on its way to the furnace or fire-
place and is caused to pass down through the fire instead of being
admitted cold and allowed to pass up through the fire according to
ordinary practice.
According to our Invention we make the fire-bars hollow, and cause
the air to pass through them into a flue or heating chamber and thence
down through the fuel, the ash-pit being closed and the necessary down-
ward draught being caused by an inverted fire-bridge, by which
arrangement we consume the smoke and economise the fuel.
In constructing a puddling or other similar metallurgical furnace
according to our Invention we fix therein the hollow fire-bars herein-
before referred to, which open at one end into the external atmosphere
and at the other into a flue communicating with a heating chamber or
heating chambers constructed between the inner and outer walls of the
fire-place, in which chamber or chambers the air is further heated, and
from which it passes through holes in the upper part of the inner wall
or walls into the fire-place, at the back or sides of which we construct
an inverted fire-bridge, descending from the roof of the said fire-place
to within such a distance of the fire-bars as to cause the heated air to
pass down through the said fire on its way to the said bridge, by which
means perfect combustion is secured, the ash-pit being closed by a door
in order to prevent air from passing up between the bars. After passing
under the said inverted bridge the hot air and gases pass over a fire-
bridge of the usual construction, and thence through the furnace to the
chimney. Openings are made in the walls of the heating chamber
aforesaid in order to admit to the fire any quantity of air which may be
required in addition to that admitted through the fire-bars, the said
openings being closed as required by means of dampers.
In constructing cupola furnaces we omit the fire-bars and surround
the wall of the furnace with an iron or other casing, between which and
the said wall we leave a space, into which we admit air direct from the
external atmosphere through the holes in the said casing. From this
casing the heated air passes into the furnace through holes in the upper
part of the wall and down through the fuel and charge in the said
furnace, and passes out through side flues in the lower part of the said
furnace into ascending flues leading to the chimney. The said side

page_text: flues (which act like so many inverted fire-bridges) are provided with
doors for the purpose of cleaning them. The furnace is constructed with
a feed door at its upper part and a discharge door at its lower part. By
this arrangement the processes of melting and separating can generally
be carried on without the mechanical appliances ordinarily used for
creating a blast, but where the substance operated upon is of a very
refractory nature a blast may be forced into the furnace through blast
pipes, the nozzles of which are inserted in the holes, which would
otherwise be used for the direct admission of air.
We construct lime kilns as above described with reference to cupola
furnaces, but fix at the bottom of the kiln fire-bars, under which we
construct an ash-pit extending out in front to admit air during the
kindling of the kiln, which being effected the ash-pit is closed.
In constructing the furnaces of ordinary egg-ended steam boilers and
of evaporating and crystallizing pans according to our Invention we fix
therein hollow fire-bars, the fore ends of which are open to the external
atmosphere. Their rear ends open into transverse flues or hollow fire-
bridges, which communicate with side flues or heating chambers formed
between the outer walls of the furnace and the inner walls or lining,
through openings in the upper part of which inner walls the air which
has been heated during its passage through the fire-bars and heating
chambers aforesaid passes into the furnace, at the back of which is an
inverted bridge of the kind herein-before described. The ash-pit .is
closed by an air-tight door. By this means the hot air is caused to pass
down through the fire on its way to the fire-bridge aforesaid, under which
it passes to the flash flue.
In constructing a Cornish boiler (i.c., a boiler having the furnace in
an inner tube or shell) according to our Invention we fix therein the
hollow fire-bars aforesaid, the forc ends of which are open to the external
atmosphere, their rear ends opening into a hollow fire bridge at the
back of the furnace over which the hot air and gases pass on their way
through the inner tube of the boiler. This bridge communicates with a
side flue at cach side, the fore ends of which flues open into an air
heating chamber constructed around the fire hole, the upper part of the
inner side of which chamber is pierced with holes through which the hot
air passes down into the furnace. The inverted fire bridge is constructed
between the fire space and the hollow bridge herein-before described,
A 2

page_text: and rests at each side on the aforesaid side flues, leaving a small space
between its under side and the fire-bars for the passage of the hot air,
the ash-pit being closed. The air for the support of combustion passes
through the fire-bars, hollow bridge, and flues aforesaid to the heating
chamber, from the upper part of which it descends into and through the
fire on its way to and under the inverted fire-bridge, whence it passes
over the hollow fire-bridge into the inner tube or shell of the boiler.
Where the internal flue of the boiler is less than 22 feet in diameter
the furnace should be constructed outside the boiler, as herein-before
described with reference to an egg-ended boiler, and in any case this 1
latter plan may be adopted.
In constructing the furnaces of locomotive and portable engines
according to our Invention we prefer to use solid fire-bars, and construct
in the interior of the fire-box and at each side thereof flues or air heating
chambers, the lower ends of which are open to the external atmosphere 1
and wider at the ends facing towards the front of engine, their upper
ends opening into a transverse flue above the fire hole, which flue is
pierced with openings through which the heated air passes down into
the furnace, in which we construct an inverted fire-bridge, which may
be either made of ganister brick, by which means an ordinary locomotive
or other fire-box boiler may be altered according to our principle at a
small cost, or a hollow inverted fire-bridge made of copper or iron boiler
plate may be used, such bridge communicating with the water space
between the outer and inner sides of the fire-box. This bridge descends
to within a few inches of the fire-bars, so that the hot air issuing from
the heating flues is caused to pass down through the fire and under the
said bridge before entering the boiler tubes, the ash-pan being closed by
an air-tight door. The air-heating flues may be provided with slides or
dampers for regulating the draught.
The furnaces of marine steam boilers may be constructed according to
our Invention essentially as herein-before described with reference to the
furnaces of locomotive boilers.
In constructing stoves for heating and cooking purposes according to
our Invention we can fix therein the hollow fire-bars herein-before
referred to, the rear ends of which open into a hot air chamber, from
which the hot air may be conducted by flues to any point at which it is
required, whether for the warming of rooms, greenhouses, drying closets,

page_text: or otherwise. At each side of the front plate we construct air-heating
flues, which open into a transverse flue over the fire hole through holes
in the inner side of which flue the hot air passes down into the fire-place.
The inverted fire-bridge is built across the stove at the middle thereof.so
as virtually to divide it into two compartments, the first of which is the
fire-place herein-before referred to, the second constituting a receiving
chamber, over which is a hot plate, and at the sides are or may be
constructed an oven and a boiler respectively, which are heated by side
flues from the said receiving chamber, which flues open into the
chimney. The several flues are provided with dampers for cutting off
or regulating the draught as required. The stove has three doors, viz.,
the fire hole door, a door for heating flat irons and other articles, and
the ash-pit door..
In applying our Invention to cooking and heating stoves with open
fire-places we arrange the hollow fire-bars and the hot air chamber as
described with reference to the arrangement herein-before last described.
The ash-pit is closed by doors. Below the fire-place is a drawer, in
which the said hollow fire-bars are fixed. In the said drawer are
openings, through which the flame and heat from the fire pass into a
chamber or chambers formed at the sides and back of the fire-place,
which chamber or chambers is or are covered by hot plates, and com-
municates or communicate by means of flues provided with dampers
with other flues passing to the chimney and around the oven and boiler.
Solid fire-bars may be used in this arrangement instead of hollow bars
where it is not convenient to use the heated air as before mentioned.
The hot air from the hot air chamber may be conveyed by flues to any
point desirable provided the outlet is at a higher level than the inlet.
Instead of allowing the waste heat to pass into the chimney of the room
in which the stove is situated it may be used for warming another room
on the opposite side of the wall by conducting the said waste heat
through the wall into the fire-place of the latter room, and there passing
it through clinkers, or any material of a similar character, after which it
may be allowed to escape up the chimney.
In constructing stoves to be used solely for heating we make them
with an external casing for heating the air, which when so heated is
allowed to pass into the hot air flue to be disseminated as required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles Edward Bainbridge and William Pinkney
in the Great Seal Patent Office on the 17th December 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wе, CHARLES
EDWARD BAINBRIDGE, of Middleton-in-Teesdale, in the County of
Durham, Superintendent of Lead Smelting Works, and WILLIAM
PINKNEY, of Eggleston, in the County of Durham, Engineer and
Superintendent of Saw Mills, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Seventeenth day of June, in the
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto us, the said Charles Edward Bainbridge
and William Pinkney, Her special license that we, the said Charles
Edward Bainbridge and William Pinkney, our executors, administrators,
and assigns, or such others as we, the said Charles Edward Bain-
bridge and William Pinkney, our 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, FIRE-PLACES,
AND STOVES," upon the condition (amongst others) that we, the said
Charles Edward Bainbridge and William Pinkney, our executors or
administrators, by an instrument in writing under our or their hands
and seals, or under the hand and seal of one of us or them, should par-
ticularly 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 we, the said Charles Edward Bainbridge and
William Pinkney, 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 :-
Our Invention relates to metallurgical and other furnaces used for

page_text: manufacturing purposes, the furnaces of stationary, marine, and loco.
motive steam boilers, and to cooking and heating stoves and fire-places.
According to some arrangements of our Invention we make the fire-
bars hollow and cause the air for the support of combustion to pass
through them into flues or heating chambers, and thence down through
the fuel, the ash-pit being closed and the necessary downward draught
being caused by an inverted fire-bridge or its equivalent, by which
arrangement we consume the smoke and economize the fuel.
According to the other arrangements of our Invention we cause the air
for the support of combustion to pass direct to the heating chamber or
to the fuel.
In constructing a puddling or other like metallurgical furnace
according to our Invention we fix therein the hollow fire-bars, herein-
before referred to, which at one end communicate with the external
atmosphere and at the other end open into a heating chamber, which
communicates with another heating chamber or other heating chambers
formed within the side wall or walls of the fire-place, in which chamber.
or chambers the air is further heated, and from which it passes through
holes in the upper part into the fire-place, at the back or side of which.
we construct an inverted fire-bridge, which descends from the roof of
the said fire-place to within such a distance of the fire-bars as to cause
the heated air to pass down through the said fire on its way to the said
bridge, by which means perfect combustion is secured, the ash-pit being
closed by a door in order to prevent air from passing up between the
bars. After passing under the said inverted bridge the hot air and
gases pass over a fire-bridge of the usual construction, and thence:
through the furnace to the chimney. Openings are made in the walls
of the side heating chamber aforesaid in order to admit to the fire any.
quantity of air which may be required in addition to that admitted
through the fire-bars, the said openings being closed as required by
means of dampers.
Figures 1 and 2 represent in vertical section and horizontal section.
respectively part of a metallurgical furnace constructed according to
our Invention. The vertical section is taken on the line 1, 2, Figure 2, .
and the horizontal section is taken on the line 3, 4, Figure 1. A, A, are
the hollow fire-bars; B, B', are heating chambers formed in the side
wall of the furnace; 6', 6', are holes forming the communication between":
-

page_text: the chamber B' and the fire-place; C is the inverted fire-bridge; D is a
fire-bridge of the usual construction; 6², 62, are openings by which air
may be admitted direct from the exterior of the furnace to the chamber
B' is a damper for regulating the quantity of air so passing; E is a
door by which the ash-pit is closed.
The action of the furnace is as follows:-Air for the support of com-
bustion passes through the hollow fire-bars A into the chamber B,
becoming heated in its passage; thence it passes into the chamber B',
where it is further heated, and from which it passes through the openings
b', b', on to and through the fuel in the fire-place, whence the hot air
and gases pass under the inverted fire-bridge C and over the ordinary
fire-bridge D to the chimney (not shown in the Drawings). Air is
prevented from passing up in the ordinary manner between the bars into
the fire-place by means of the door E, which closes the ash-pit. When
the amount of air passing through the fire-bars A is insufficient for the
support of combustion air may be admitted direct into the heating
chamber through the openings 62, 62. The course of the air and gases
in the arrangement of furnace illustrated in Figures 1 and 2 (as in each
of the other arrangements illustrated), is indicated by arrows.
In constructing lime kilns according to our Invention we close the
communication between the interior of the kiln and the chimney by
means of a roof, and partly surround the wall of the kiln with curved
plates, between which and the said wall we leave spaces, into which we
admit air direct from the external atmosphere through holes in the said.
plates. In the upper part of the wall of the furnace we make holes,
through which the heated air passes from the spaces aforesaid down
through the fuel and charge in the kiln, the said air thence passing out
through side flues in the lower part of the said kiln into ascending flues
which enter the chimney above the roof of the kiln. The said side
flues, each of which acts like the openings under the inverted fire-
bridge, described and illustrated with reference to Figures 1 and 2, are
provided with doors, by which access may be obtained to them for the
purpose of cleaning them. The usual feed door is made at the upper
part of the kiln and a discharge door at the lower part. The ash-pit is
closed by a door. An opening is made in the roof of the kiln, through
which direct communication with the chimney is established while the
fire is being lighted, the air being then allowed to enter the kiln by the

page_text: ash-pit, the door of which is at this time opened. After the fire has
been lighted the said door and the opening in the roof are closed.
Figure 3 is an elevation, and Figure 4 is a horizontal section, and
Figures 5 and 6 are vertical sections of a lime kiln, showing the appli-
cation of our Invention thereto. The section, Figure 4, is taken on the
line 5, 6, Figure 3; the section, Figure 5, is taken on the line 7, 8,
Figure 4; and the section, Figure 6, is taken on the line 8, 9, Figure 4.
A is the wall of the kiln, the communication of which with the chimney
(part of which is shown at B) we close by means of the roof C;
D, D, are the iron plates aforesaid surrounding those parts of the wall A
which lie between the flues c¹, e¹;-d', d', are the holes in the plates D, D;
a', a', are the holes in the wall A of the furnace; E, E, are the side
flues, and e¹, e¹, are the ascending flues; e¹², e², are doors closing.
apertures e, e, in the said ascending flues e, e¹, through which
apertures access may be obtained for cleaning the flues. c¹ is the feed
hole, and a is the discharge door; c² is the opening in the roof C, which
is closed when the furnace is in action by means of a damper consisting.
of a block of fire-clay F affixed by an iron frame f¹ to a rod ƒ³, by.
which the said damper can be slidden as required; G, G, are the fire-bars,
and 9' is the ash-pit door. When the fire is lighted and the opening c³
and the ash-pit door g' are closed the air for the support of combustion
enters the spaces enclosed between the plates D and the wall A through
the holes d¹ in the said plates. In passing through the said spaces the
air becomes heated and passes into the kiln through the holes a¹ in the
wall A. The air then descends through the fuel and charge in the
furnace and passes out through the side flues E, E, in the ascending
flues e¹, e¹, and so into the chimney B.
Instead of building the chimney over the kiln it may be built on a
separate foundation at any convenient point, in which case the
ascending flues communicate with a horizontal or inclined flue leading
to the said chimney.
In applying our Invention to the furnaces of evaporating and
crystallizing pans and of ordinary egg-ended steam boilers we fix in
such furnaces hollow fire-bars, the fore ends of which are open to the
external atmosphere, their rear ends opening into transverse flues or
hollow fire-bridges, which communicate with side flucs or heating
chambers formed between the fire-brick lining and the outer brick.

page_text: casing of the fire-place. In the said fire-brick lining we make openings
through which the air after passing through the fire-bars and heating
chambers aforesaid passes into the furnace, at the back of which is an
inverted fire-bridge of the kind herein-before described. The ash-pit is
closed by an air-tight door. By these means the hot air is caused to
pass down through the fire on its way to the fire-bridge aforesaid, under
which it passes to the flash flue.
Figure 7 is a vertical section (taken on the line 9, 10, Figure 8), and
Figure 8 is a horizontal section (taken on the line 10, 11, Figure 7),
showing the application of our Invention to the furnace of a crystallizing
pan. A, A, are the hollow fire-bars; B is the transverse flue or hollow
fire-bridge which is made of cast iron; c¹, c¹, are the side flues or
heating chambers formed in the brickwork C at the sides of the furnace,
with which flucs or chambers the said fire-bridge B communicates at its
ends; c, c, are holes formed in those portions of the brickwork C
which divide the heating chambers from the fire-place; D is the
inverted fire-bridge, and E is the ash-pit door; F is the firing door, and
G is the stoking door; c³, c³, are apertures by which cold air may be
admitted to the heating chambers c¹, c¹; c, c², are dampers by means of
which the said apertures may be closed or partly closed as required.
When the furnace is in action air enters the hollow bars A, A, and
passes through them into the hollow bridge B, thence into the heating
chambers c¹, c', and through the holes c², c², into the fire-place, through
the fuel, under the inverted bridge D, over the fire-bridge B into the
flash flue, and thence by the ordinary flues into the chimney. In this
arrangement the fire-place is larger at the back than at the front, the
object being to prevent obstruction to the passage of the flame and heat
into the furnace which might otherwise occur, owing to the inverted
fire-bridge being built across the fire-place. The said arrangement is
applicable in all cases where the passage of the flame and gases would
otherwise be impeded by the narrowness of the opening under the
inverted fire-bridge.
Figure 9 is a vertical section (taken on the line 11, 12, Figure 10),
and Figure 10 is a sectional plan (taken on the line 12, 13, Figure 9),
showing the application of our Invention to evaporating pans.
Figure 11 is a front elevation, Figure 12 is a vertical longitudinal
section taken on the line 13, 14, Figure 11, and Figure 13 is a transverse.

page_text: section taken on the line 14, 15, Figure 12, showing the application of
our Invention to the furnace of an ordinary egg-ended steam boiler.
The several parts of the furnaces illustrated in Figures 9, 10, 11, 12,
and 13 being marked with the same letters and figures of reference as
those used for similar parts already described with reference to Figures 7
and 8 we do not consider it necessary to repeat the description.
In applying our Invention to a Cornish boiler (i.e. a boiler having the
furnace in an inner tube or shell), we fix therein the hollow fire-bars
aforesaid, the fore ends of which are open to the external atmosphere,
their rear ends opening into a hollow fire-bridge at the back of the
furnace, over which the hot air and gases pass on their way through
the inner tube of the boiler. This bridge communicates at each end
with a side flue, the fore ends of which flues open into an air-heating
chamber constructed around the fire-hole, the upper part of the inner
side of which chamber is pierced with holes through which the hot air
passes down into the furnace. The inverted fire-bridge is constructed
between the fire space and the hollow bridge herein-before described,
and rests at each side on the aforesaid side flues, a space being left
between its under side and the fire-bars for the passage of the hot air.
The ash-pit is closed. This arrangement of our Invention is illustrated
in Figures 14, 15, and 16, Figure 14 being a front elevation,
Figure 15, a longitudinal section taken on the line 15, 16, Figure 14,
and Figure 10, a transverse section taken on the line 16, 17, Figure 15.
A, A, are the hollow fire-bars supported by bearers a¹, a¹; B is the
hollow fire-bridge; C, C, are the side flues, which we prefer to cast in
one piece with the said hollow bridge B; is a covering of ganister
brick which protects the cast iron from the action of the fire; D is the
air-heating chamber with which the side flues C, C, communicate.
This chamber is formed around the fire-door between the plate d' which
closes the end of the inner tube of the boiler and the lining d² of the said
plate; d³, d³, are the holes in the said lining, through which holes the
heated air passes from the chamber D; E (see Figure 15) is the inverted
fire bridge, which is made of ganister brick and is supported on the side
flues C, C. A space is left between the under side of the bridge E and
the fire-bars A, A, for the passage of flame and heated air from the
fire. d is the stoking door; d is the fire-door; de is a ventilator in
the said door by means of which and the stoking door d' air may, when
necessary, be admitted direct to the furnace; F is a door by which air

page_text: is prevented from entering the ash-pit. Air for the support of com-
bustion passes through the fire-bars A, A, hollow bridge B and
flues C, C, to the heating chamber D, whence it passes by the
holes d³, d³, to the fire-place and through the. fire under the inverted
bridge E and over the hollow fire-bridge B into and through the boiler
flues to the chimney. When the amount of air passing through the
fire-bars is insufficient the stoking door d and the ventilator de may bc
opened, thereby admitting air direct to the fire.
Instead of arranging the furnaces in Cornish boilers, as herein-before
described, they may be constructed outside the boilers, as illustrated in
Figures 17 and 18, in which the several parts are marked with the same
letters of reference as the corresponding parts in Figures 1 and 2, the
description of which Figures applies here also. Figure 17 is a section
on the line 17, 18, Figure 18; and Figure 18 is a section on the line 18,
19, Figure 17. This arrangement, which is equally applicable to boilers
having a single internal tube and to boilers having several internal tubes,
should always be adopted where the diameter of the internal fluc is less
than 2 feet.
The furnaces of marine steam boilers may be constructed according to
our Invention, essentially as herein-before described with respect to the
furnaces of Cornish boilers. Figure 19 is a vertical section taken on the
line 19, 20, Figure 20, and Figure 20 is a vertical section taken on the
line 21, 22, Figure 19, of a marine boiler to the furnace of which our
Invention is applied. In these Figures the same parts are indicated by
the same letters, as in Figures 14, 15, and 16, the description of which
Figures applies here also.
In applying our Invention to the furnaces of locomotive and portable
engines we prefer to use solid fire-bars, and we arrange in the interior of
the fire-box a flue; the ends of which are open to the external atmosphere,
and are affixed to the lower part of the fire-box, to the roof and sides of
which the intermediate portions of the said flue are affixed, that portion
of the said flue which is affixed to the roof being pierced with holes,
through which the heated air passes down into the furnace in which we
construct an inverted fire bridge. This bridge descends to within a
short distance of the fire-bars, so that the hot air issuing from the air
heating flue is caused to pass down through the fire and under the said
bridge before entering the boiler tubes, the ash-pan being closed by an

page_text: air-tight door.
This application of our Invention is illustrated in
Figures 21 and 22 of the accompaying Drawings. Figure 21 is a
transverse section of the fire-box of a locomotive engine, the section
being taken on the line 23, 24, Figure 22; and Figure 22 is a longi-
tudinal section of the fire-hox and part of the boiler taken on the
line 25, 26, Figure 21. A is the air heating flue or tube, the ends (one
of which is shewn at a, Figure 22) being enlarged and open to the
external atmosphere; a², a², are the holes in that part of the said flue or
tube which is affixed to the roof of the fire-box; B is the inverted fire
bridge which may be made of ganister brick, by using which an
ordinary locomotive or other fire-box may be altered according to our
Invention at a small cost. Or a hollow inverted fire bridge made of
copper or iron boiler plate may be used, such bridge communicating
with the water space around the fire-box. C is the door or flap by
which air is prevented from entering the ash-pan. Air for the support
of combustion enters the flue A at a¹, and passes out of the said flue at
the holes a², a². The said air (which is heated in its passage through
the flue A) then passes down through the fire and under the bridge B to
the boiler flues. We prefer that the open ends of the flue A should.
face in the direction in which the engine is moving; therefore when our
Invention is applied to an engine, which is required to run either end
forward, we connect to the said flue near each end thereof a short branch
flue, as indicated in dotted lines in Figure 22, and we provide the open
ends of the said flue and branch flues with valves, by means of which air
may be admitted from either direction, and the draught may be regu-
lated as required. Additional air may be admitted if necessary through
the fire-hole or through holes in the fire-hole door.
In constructing stoves for heating and cooking purposes according
to our Invention we fix therein either hollow or solid fire-bars.
When we use hollow bars we form at the back of the stove a chamber
into which the rear ends of the hollow bars open, and from which
the hot air, passing in through the said hollow bars, may be conducted
by flues to any point at which it is required, whether for the warming
of rooms, greenhouses, drying closets, or otherwise. At each side of
the front plate we construct air-heating flues which open into a
transverse flue over the fire-hole, through holes in the inner side of
which flue the hot air passes down into the fire-place. The inverted
fire-bridge is built across the stove at the middle thereof so as virtually

page_text: to divide it into two compartments, the first of which is the fire-place
herein-before referred to, and the second constitutes a receiving chamber
over which is a hot plate, and at the sides are or may be constructed
an oven and a boiler which are heated by side flues from the said
receiving chamber, which flues open into the chimney. The several
flues are provided with dampers for cutting off or regulating the draught
as required. The stove has three doors, viz., the fire-hole door, a door
for heating flat irons and other articles, and the ash-pit door.
Figure 23 is a front elevation (partly in section) of a stove con-
structed according to our Invention, and Figure 24 is a section of
the said stove taken on the line 29, 30, Figure 23. A, A, are the
hollow firc-bars; B is the chamber into which their rear ends
open; b¹ is a pipe by which the heated air may be conveyed from
the chamber B to the place where it is required; C is the front
plate; c', c¹, are the side air-heating flues; and c² is the transverse
air-heating flue; c³, c³, are holes in the latter flue. These flues c¹, c',
and care shewn in section taken on the line 27, 28, Figure 24;
cis the fire-hole door; c is a door or flap which when opened
rests on brackets c, c, so as to form a shelf for supporting flat irons
or other articles while being heated; c' is the door by which the 2
ash-pit is closed; E is the fire-place into which the hot air passes
from the transverse flue c²; F is the inverted fire-bridge which is
built across the stove%3B G is the receiving chamber, and 9 is the
hot plate; H is the oven, and I is the boiler; J is the chimney;
h¹ and are the flues leading from the receiving chamber G to the 2
chimney J, by which flues heat is conveyed to the said oven and
boiler; is a flue which communicates between the receiving
chamber G and the chimney J; g³, h², and 12 are dampers by which
the draught through the flues G, H, and I may be cut off or regulated
as required. The sides and fire-bridge of the stove are made of fire- 3
clay.
In addition to the air-heating flues c¹, c², other air-heating flues
or chambers may be formed at the sides of the fire-place, through
which chambers air for the support of combustion passes into the
said fire-place by the holes indicated by the dotted circles in Figure 24. 3
In constructing cooking and heating stoves with open fire-places
according to our Invention we arrange the hollow fire-bars and the hot-

page_text: air chamber, as described with reference to the arrangement herein-
before last described. The ash-pit is closed by doors. Below the fire-
place is a drawer in which the said hollow fire-bars are fixed. In the
sides of the said drawer are openings through which the flame and heat
from the fire pass into a chamber or chambers formed at the sides and
back of the fire-place, which chamber or chambers is or are covered by
hot plates, and communicates or communicate by means of flues
provided with dampers with other flues passing to the chimney and
around the oven and boiler. This arrangement is illustrated in
Figures 25, 26, and 27 of the accompanying Drawings, Figure 25 being
a front elevation of the stove; Figure 26, a horizontal section; and
Figure 27, a vertical section of parts of the said stove, the said sections
being taken respectively on the lines 31, 32, and 33, 34, Figure 25.
A, A, are the hollow fire-bars; B is the hot-air chamber; C is the ash-
pit, which is closed by a door or plate c²; D is the fire-place; E is a
drawer in which the bars A, A, are fixed. In the sides of this drawer,
which forms the bottom of the fire-place, are openings e¹, e¹. F is the
chamber formed at the back and sides of the fire-place D, with which
fire-place the said chamber communicates by means of the said
openings e¹, e¹, in the drawer E; G is the oven; H is the boiler; I is the
chimney; g', h¹, are the flues which lead from the chamber F around
the oven and boiler respectively and terminate in the chimney; f¹‚ƒ³, are
flues which lead directly from the chamber F to the chimney; f³ is a
flap covering an opening, through which any vapour or smoke which
does not pass through the fire passes into the chimney; g², h², f³,ƒ³, aro
dampers by which the draught in the respective flues may be regulated;
f is the hot plate covering the chamber F. Air for the support of
combustion enters the fire-place D at the uncovered front and top
thereof, and passes down through the fuel. It then passes through the
holes c¹, e, in the drawer E into the chamber F, the said holes' e¹, e¹,
acting like inverted fire bridges. From the chamber F the hot air and
gases pass into the flues g¹³, h', f¹, f, and so to the chimney. The hot
air from the hot-air chamber B may be conveyed by flues to any point
desirable, provided the outlet is at a higher level than the inlet. Where
the hot air is not required to be so used the hot-air chamber may be
dispensed with and solid fire-bars used instead of hollow bars.
Where the fire-place is required only to warm the room in which it
is sot the oven. and hoilor and the hollow fire-bars and chamber B

page_text: may be dispensed with, the inverted fire bridge (formed by the sides and
back of the fire-place), the closed ash-pit, and the flues f¹, f, only
being retained. Figure 28 is a
Figure 28 is a transverse section taken on the
line 35, 36, Figure 29; and Figure 29 is a longitudinal section taken
on the line 37, 38, Figure 28 showing the said arrangement thus
modified. a is the fire-place, the sides and back of which descend to
within a short distance of the bars forming the bottom thereof; 6 is the
chamber formed at the back and sides of the fire-place; c¹, c¹, are the
side flues which lead from the said chamber 6 to the chimney d; c² is a
damper by which the draught through the said flues c¹, c', may be
regulated as required; e is a moveable plate by which the ash-pit is
closed; is a flap by which direct communication between the fire-
place and the chimney may be established when necessary. The action
of this arrangement is similar to that of the arrangement herein-before
last described and illustrated in Figures 25, 26, and 27, i.c., the air
enters the fire-place at the front and top and passes down through the
fuel and under the sides and back of the fire-place into the chamber b,
whence it passes through the flues c¹, c³, into the chimney d.
In constructing stoves to be used solely for heating we arrange the
hollow fire-bars, the air heating flues, and the inverted fire-bridge, as
herein-before described, and we make the said stoves with an external
casing for heating the air, which when so heated is allowed to pass
cither into the room in which the stove is placed or into the hot-air flue
to be disseminated as required.
Figure 30 is a front clevation; Figure 31 is a section taken on the
line 39, 40; Figure 30 and Figure 32 is a section taken on the line
41, 42, Figure 31, of a heating stove constructed as above described.
a, a, are the hollow fire-bars; b is the transverse heating flue; c, c, are
the side heating flues; d, is an air casing which we term the saddle,
which casing forms the sides and roof of the fire-place, the said sides
acting like inverted fire-bridges; e¹ is a front air heating chamber, into
which air enters at the lower part, which is open. Air passes from the
said casing to the fire-place through holes, one of which is shown at c²,
Figure 31. The flues c, c, and the casing d, communicate with the said
front air heating chamber e¹; f is the chimney; g¹ is the outer
casing; 9², 9, 9³, g³, are holes in the said outer casing, and h¹ is a
chamber formed therein at the back of the fire-place, which chamber
communicates with the "saddle" d. is a flue by which the hot air

page_text: •
from the chamber * and "saddle" & may be conveyed where required;
i is the ash-pit door. Air enters the stove by the hollow fire-bars a, a,
and the front air heating chamber e¹. The air entering by the fire-bars
passes through the flues b, c, into the front chamber e', where the
current divides, part passing through the holes into the fire-place,
thence under the sides of the "saddle" d to the outside thereof, and so
into the chimney f, and part passing through the "saddle d and
chamber h¹ to the flue 3. The front casing e¹ is open at bottom so as
to admit air which mingles with and takes the same course or courses
as the air from the fire-bars and heating flues.
"
Air enters the outer casing g' by the holes and leaves it by the
holes g³ becoming heated in its passage. The room in which the stove
is set is heated partly by the air passing through the said outer casing
and partly by heat radiated from the said stove.
1
Having now described the nature of our Invention, and the manner.
in which the same is to be performed, we wish it to be understood that
we do not limit ourselves to the precise details herein-before described,
as the same may be varied without departing from the nature of our
said Invention, neither do we claim any of such details separately, but
we claim as our Invention,-
Firstly. The improvements in furnaces herein-before described and
illustrated in Figures 1, 2, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
and 20 of the accompanying Drawings, that is to say, constructing the
furnace with hollow fire-bars, air heating flues or chambers, an inverted
fire-bridge, and an ash-pit door, which parts are so arranged relatively to
one another that the air used for the support of combustion shall be
caused to pass first through the said hollow fire-bars, then through the
said air heating flues and chambers, thence into the fire-place, and down
through the fire, essentially as described.
Secondly. The improvements in lime kilns herein-before described and
illustrated in Figures 3, 4, 5, and 6 of the accompanying Drawings, that
is to say, constructing such kilns with roofs to divide the body of thie
kiln from the chimney, and with air heating spaces or chambers leading.
into the upper part of the kiln, and with exit flues, the lower ends of
which act as inverted fire-bridges, which flucs lead from the lower part!
of the kiln to the chimney, the air heating chambers and exit flucs
being so arranged that the air used for the support of combustion shall>

page_text: be heated on its way to and shall pass down through the fuel and charge
in the kiln, essentially as described.
Thirdly. The improvements in the furnaces of locomotive engines
herein-before described and illustrated in Figures 21 and 22 of the
accompanying Drawings, that is to say, applying to the interior of the
furnace an air heating flue and an inverted fire-bridge, and closing the
'ash pan by a door or flap so as to heat the air used for the support of
combustion, and cause it to pass down through the fire, essentially as
described.
•
· Fourthly. The improvements in heating and cooking stoves herein-
before described and illustrated in Figures 23 and 24 of the accompany-
ing Drawings, that is to say, constructing the stove with air heating
flues or chambers, an inverted fire-bridge, a combustion chamber, ash-
pit, and other doors and flues passing under, over, or around an oven and
boiler, the construction and relative arrangement of the parts being such
that the air used for the support of combustion shall be caused to pass
through the said heating flues and thence down through the fire,
essentially as described, the said stove being furnished either with solid
fire-bars or with hollow fire-bars leading to an exit fluc as represented.
Fifthly. The improvements in open ranges herein-before described and
illustrated in Figures 25, 26, and 27 of the accompanying Drawings,
that is to say, constructing the fire-places of such ranges with openings.
which act as inverted fire-bridges, and communicate with a chamber,
from which flues lead to the chimney and around an oven and boiler,
the ash-pit being closed and the construction and relative arrangement
of the parts being such that the air used for the support of combustion
shall be caused to pass down through the fire, essentially as described,
the said ranges being furnished either with solid fire-bars or with hollow
fire-bars leading to an exit flue, as represented.
Sixthly. The modification herein-before described and illustrated in
Figures 28 and 29 of the accompanying Drawings of the arrangement
referred to in our fifth claim, that is to say, making open fire-places for
warming with openings in the lower parts of the sides and backs thereof,
so that such sides and backs shall act as inverted fire-bridges, under
which the gaseous products of combustion pass to flues leading to the a
chimney, the ash-pit being closed as and for the purpose described.

page_text: Seventhly. The improvements in stoves for heating herein-before
described and illustrated in Figures 30, 31, and 32 of the accompanying
Drawings, that is to say, constructing such stoves with hollow fire-bars
and air-heating flues and casings or chambers, and closing the ash-pits,
the construction and relative arrangement of the parts being such that
the air used for the support of combustion shall be heated on its way to
the fire, and shall pass down through it, and thence to the chimney,
heating on its way from the fire to the said chimney the air passing
through the outer casings or chambers, essentially as described.
In witness whereof, we, the said Charles Edward Bainbridge and
William Pinkney, have hereunto set our hands and seals, this
Fifteenth day of December, in the year of our Lord One
thousand eight hundred and seventy-four.
Witness to this
signature,
CHARLES EDWARD BAINBRIDGE. (L.S.)
JOSEPH PATTINSON.
Witness to this
signature,
WILLIAM PINKNEY.
THOMAS STODDART.
(L.S.)