IMPROVEMENTS IN FURNACES
Year: 1882

page_text: LETTERS PATENT to William Morgan-Brown, Patent Agent of 38 Southampton
Buildings, London, for an Invention of "IMPROVEMENTS IN FURNACES." A
communication from abroad by Alexander C. Felton, of Warwick, County of
Franklin, Massachusetts, United States of America.
PROVISIONAL SPECIFICATION left by the said William Morgan-Brown at
the Office of the Commissioners of Patents on the 7th February 1882.
WILLIAM MORGAN-BROWN Patent Agent of 38 Southampton Buildings London,
"IMPROVEMENTS IN FURNACES." [A communication from abroad by Alexander"
C. Felton, of Warwick, County of Franklin, Massachusetts, United States of
America.]
This Invention relates to furnaces and has for its objects to prevent the formation
of clinkers on the furnace walls and to produce more perfect combustion of the
fuel.
The Invention is in this instance described as applicable to a reverberatory
furnace such as is commonly used for smelting, puddling and similar metallurgical
or chemical operations but it is also applicable to furnaces used for other purposes
as for example generating steam.
Furnaces of this class have been heretofore commonly constructed with a
substantially horizontal grating forming the bottom of the fire chamber from
which arise vertical walls of fire brick or other refractory material which con-
stitute the sides of the said chamber the draught or air for combustion passing
into the said fire chamber to combine with the fuel therein through the said
bottom grating.
In furnaces of such construction clinkers form on the heated side walls adhering
firmly thereto and gradually aggregating soon form a solid mass extending into
the mass of fuel above the grate and obstruct the draught or clog the furnace so
that it ceases to operate properly whereupon the fire has to be dumped or removed
and the said mass of clinker to be forcibly broken from the walls to clear the
furnace.

page_text: This clearing operation besides consuming much time and labor causes a
considerable waste of fuel owing to the heat lost in the process of removing the
fire and clinkers and the heat which is consumed in raising the temperature of the
furnace and ore chambers or boilers or equivalent and is consequently diverted from
performing its proper function of reducing ore evaporating water or attaining other
desired results.
This Invention consists in the fuel supporting grating of a furnace and the fire
chamber having its side walls inclined inward and upward from the edges of the
said grating towards the middle of the furnace to reduce the pressure of the fuel
against the side walls and thereby prevent the adhesion of clinker material
thereto.
Also in the combination of the upwardly extending gratings at the sides of a
furnace with side dampers to control the draught or flow of air through the said
gratings.
Also in the employment in a furnace provided with upwardly extended side
gratings of side dampers to control the draught through the said gratings and
damper operating mechanism to move all the said dampers simultaneously.
Also in the bearing bar of the furnace grate having two ribs each to support the
ends of adjoining sections of grate bars, and provided with notches to insure the
proper spacing of the said bars, combined with grate bars, having notches to
engage and be held in place by the said notched ribs.
Also in removable side bars of a furnace grating bevelled at their ends to enable
them to be readily removed from their supports.
Also in the combination in a furnace of the bottom or floor grating with upright
gratings the bars of which are tapered from end to end in their thickness measured
parallel with the walls of the furnace that they constitute to afford a variable
amount of space for the passage of air between them.
-Also-in-a-series of bars connected together to form a continuous grating and
strung or mounted at one end upon a rod-pivoted-and-supported on a suitable
bearing bar, combined with a removable support for the end of the said bars
whereby the entire connected grating may be permitted to turn on the pivoted rod
to remove the fire or fuel from the furnace.
Also in the following elements of a furnace in combination, a bottom or floor
grate, upright gratings on all sides thereof, a perforated refractory liuing above
the said upright gratings: and a continuous air passage behind the said upright
grating and refractory lining.
Also in the main bearing bar of a grate provided with notched wings and a
series of grate bars with perforated lugs and rods passed there through one rod
being supported in the said wings and sustaining one end of the said bars
combined with a removeable hook or support for the other end thereof.
Also in the combination of the floor or bottom grating and vertical gratings
extended upwards therefrom with a water back surrounding the fire chamber above
the said vertical gratings.
Also in the combination with the bottom or floor grating of a water back
consisting of a series of tubes surrounding or lining the wall of the furnace at the
sides of the said grating and provided with air spaces between them, gradually
diminishing in size towards the upper part of the furnace.
Also in the combination with the bottom or floor grating of the water back
consisting of a series of vertical tubes surrounding the furnace and a continuous
chamber connected with the upper ends thereof spaces being left behind and
between the said pipes for the adinission of air to the fuel.
By providing air space or draught passages on all sides of the furnace extending
above the main body of the fuel a supply of heated air is afforded to unite with
the gaseous products of combustion and thus cause the furnace to operate as what
is known as a smoke and gas consuming furnace.
The formation of clinkers is reduced by making the side walls of the furnace
incline inward above the grating instead of vertical, such construction reducing the

page_text: pressure of the incandescent fuel against the said walls and preventing the clinker
from adhering thereto in any considerable quantity it breaking away by its own
weight before a sufficient amount collects to seriously clog the furnace.
The upwardly extended portion of the grating may be supported at its upper
end and have a free space behind it or on the side away from the fuel, or the bars
may rest against the masonry of the sido walls, in which case they should have a
long and narrow cross section in order to produce air channels between the said
bars of considerable width measured from the fuel supporting face of the grate-bars
to the face thereof resting against the masonry.
The dampers employed to control the admission of air to the vertical gratings
may be dispensed with.
The vertical or upright grate bars are made tapering or broader at their upper
than at their lower ends so as to reduce the space for admission of air between
them towards the upper part of the furnace, as experiment has shown that such
distribution of the air or draft produces excellent results.
The furnace lining above the said vertical grates may be provided with
numerous small air passages.
The floor grating is so constructed that it may be readily lowered or turned
aside as a whole or in large sections to permit the withdrawal of the fuel without
necessitating the removal and replacing the separate grate bars.
In some cases the upper part of the lining of the furnace above the upright
grating may be made as a water back, a constant circulation of water being kept
up therein and the walls of the furnace are thus kept cool and clinkers offectually
prevented from forming.
The water back may be made either as a continuous chamber surrounding the
fire chamber and lining the furnace where exposed to the action of the fuel or it
may consist of a series of a horizontal pipes surrounding the furnace above the
upright grating, and having an air space behind them and spaces between them for
the passage of air into the fire, and instead of the vertical or upright grate bars,
tubes may be employed at the sides of the fire chamber connected with the main
water back and arranged for the circulation of water through them.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Morgan-Brown in the Great Seal Patent Office on the
5th August 1882.
WILLIAM MORGAN-BROWN Patent Agent of 38 Southampton Buildings London.
"IMPROVEMENTS IN FURNACES." A communication from abroad by Alexander
C. Felton of Warwick County of Franklin Massachusetts United States of
America.
This Invention relates to furnaces and has for its objects to prevent the formation
of clinkers on the furnace walls and to produce more perfect combustion of the
fuel.
The Invention is in this instance a reverberatory furnace such as is commonly
used for smelting, puddling and similar metallurgical or chemical operations, but
it is also applicable to furnaces used for other purpose, as for example, generating
steam.
Furnaces of this class have been heretofore commonly constructed with a
substantially horizontal grating forming the bottom of the fire chamber, from
which arise vertical walls of fire brick or other refractory material which
constitute the sides of the said chamber, the draught or air for combustion passing
into the said fire-chamber to combine with the fuel therein through the said bottom
grating.
In-furnaces-of such construction clinkers form on the heated side walls
adhering firmly thereto, and gradually aggregating-soon_form_a solid mass
extending into the mass of fuel above the grate and obstruct the draught or clog
the furnace so that it ceases to operate properly, whereupon the fire has to be
dumped or removed and the said mass of clinker to be forcibly broken from the
walls to clear the furnace.
&
This clearing operation besides consuming much time and labor causes
considerable waste of fuel owing to the heat lost in the process of removing the
fire and clinkers, and the heat which is consumed in raising the temperature of the
furnace and ore chambers, or boilers, or equivalent and is consequently diverted
from performing its proper function of reducing ore, evaporating water or attaining
other desired results.
This Invention consists in the fuel supporting grating of a furnace, and the fire
chamber having its side walls inclined inward and upward from the edges of the
said grating towards the middle of the furnace to reduce the pressure of the fuel
against the side walls, and thereby prevent the adhesion of clinker material
thereto.
Also in the combination of the upwardly extending gratings at the sides of a
furnace with side dampers to control the draught or flow of air through the said
gratings.
Also in the employment in a furnace, provided with upwardly extended side
gratings of side dampers to control the draught through the said gratings, and
damper operating mechanism to move all the said dampers simultaneously.
Also in the bearing bar of the furnace grate having two ribs each to support
the ends of adjoining sections of grate bars, and provided with notches to insure
the proper spacing of the said bars, combined with grate bars having notches to
engage and be held in place by the said notched ribs.
Also in removeable side bars of a furnace grating bevelled at their ends to enable
them to be readily removed from their supports.
Also in the combination in a furnace of the bottom or floor grating, with

page_text: upright gratings the bars of which are tapered from end to end in their thickness
measured parallel with the walls of the furnace that they constitute to afford a
variable amount of space for the passage of air between them.
Also in a series of bars connected together to form a continuous grating and
strung or mounted at one end upon a rod pivoted and supported on a suitable
bearing bar, combined with a removable support for the other end of the said bars
whereby the entire connected grating may be permitted to turn on the pivoted rod
to remove the fire or fuel from the furnace.
Also in the following elements of a furnace in combination: a bottom or floor
grate, upright gratings on all sides thereof; a perforated refractory lining above
the said upright gratings; and a continuous air passage behind the said upright
grating and refractory lining.
Also in the main bearing bar, of a grate provided with notched wings, and a
series of grate bars with perforated lugs and rods passed there through, one rod
being supported in the said wings, and sustaining one end of the said bars, combined
with a removeable hook or support for the other end thereof.
Also in the combination of the floor or bottom grating and vertical gratings
extended upward therefrom, with a water back surrounding the fire chamber above
the said vertical gratings.
Also in the combination with the bottom or floor grating, of a water back
consisting of a series of tubes surrounding or lining the wall of the furnace at the
sides of the said grating, and provided with air spaces between them, gradually
diminishing in size towards the upper part of the furnace.
Also in the combination with the bottom or floor grating, of the water back
consisting of a series of vertical tubes surrounding the furnace and a continuous
chamber connected with the upper ends thereof, spaces being left behind and
between the said pipes for the admission of air to the fuel.
By providing air space or draught passages on all sides of the furnace extending
above the main body of the fuel a supply of heated air is afforded to unite with
the gaseous products of combustion and thus cause the furnace to operate as what
is known as a smoke and gas consuming furnace.
The formation of clinkers is reduced by making the side walls of the furnace
incline inward above the grating instead of vertical, such construction reducing
the pressure of the incandescent fuel ngainst the said walls and preventing
the clinker from adhering thereto in any considerable quantity, it breaking away
by its own weight before a sufficient amount collects to seriously clog the
furnace.
The upwardly extended portion of the grating may be supported at its upper
end and have a free space behind it or on the side away from the fuel, or the bars
may rest against the masonry of the side walls, in which case they should have a
long and narrow cross section in order to produce air channels between the said
bars of considerable width measured from the fuel supporting face of the grate-bars
to the face thereof resting against the masonry.
The dampers employed to control the admission of air to the vertical gratings
may be dispensed with.
The vertical or upright grate bars are made tapering or broader at their upper
than at their lower ends so as to reduce the space for admission of air between
them towards the upper part of the furnace, as experiment has shown that such
distribution of the air or draft produces excellent results.
The furnace lining above the said vertical grates may be provided with numerous
small air passages.
The floor grating is so constructed that it may be readily lowered or turned
aside as a whole or in large sections to permit the withdrawal of the fuel without
necessitating the removal and replacing the separate grate bars.
In some cases the upper part of the lining of the furnace above the upright
grating may be made as a water back, a constant circulation of water being kept

page_text: up therein and the walls of the furnace are thus kept cool and clinkers effectually
prevented from forming.
The water back may be made either as a continuous chamber surrounding the
fire chamber and lining the furnace where exposed to the action of the fuel or it
may consist of a series of horizontal pipes surrounding the furnace above the
upright grating, and having an air space behind them and spaces between for
the passage of air into the fire, and instead of the vertical or upright grate bars,
tubes may be employed at the sides of the fire chamber connected with the main
water back and arranged for the circulation of water through them.
Figure 1 is a central longitudinal section of a furnace constructed in accordance
with this Invention, the side gratings having a free air space behind them controlled
by side dampers. Figure 2, a transverse section thereof on line x-x Figure 1 a
portion of the bottom grate bars being removed. Figure 3 a perspective diagram
showing the damper operating mechanism. Figure 4 a longitudinal section in
which the side dampers are dispensed with, the bottom grating made in sections
hinged or pivoted for dumping, and the refractory portion of the side wall above
the vertical grating is perforated for the admission of air. Figure 5 a transverse
section of a furnace in which the gratings are similar to those shown in Figure 4
but a water back is employed above the vertical gratings. Figure 6 a longitudinal
section showing another form of water back consisting of horizontal tubes. Figure 7
a modification showing still another form of water back in which the vertical grate
bars are replaced by tubes. Figure 8 a horizontal section on a smaller scale of the
furnace shown in Figures 6 and 7, and Figures 9 and 10, modifications of the
vertical grating to be referred to.
The fire chamber a provided with a fuel supplying opening b and the ash pit c
may be of any suitable shape and dimensions.
As herein shown the side walls d e are of masonry provided with an external
...plate fof iron.
The main horizontal grating g Figures 1 and 2 is supported on bearing-bars-h-
resting on piers i of masonry at the ends of the ash pit.
The grating or portion of the fire chamber constructed to allow the free passago
of air is extended upward at the sides of the fire chamber a nearly to the top of
the portion to be occupied by the fuel, the front and rear portions of the grate
being shown in Figure 1 as formed of curved bars j, resting at one end on the
bearing bars h and extending therefrom a short distance horizontally to form with
the grate g the bottom of the fire chamber after which they curve upward and are
shown in Figures 1 and 2 and are supported at their upper ends on a bar kextended
across the furnace and supported in the side walls d e.
It will be seen that the grate bars j at the front and rear of the furnace form a
portion of the bottom of the furnace and the bearing bars h are placed in a
favorable position to sustain the weight of the fuel.
The side bars at the ends of the furnaces might be made similar to the ones j
at the front and rear by arranging suitable bearing bars across between the
transverse bars h but it is more convenient to let the bars g and j occupy the whole
width of the furnace to form the entire bottom thereof while the bars merely.
extend upward to form the end sides, they being supported at their lower ends
on suitable bearing bars m, resting in slots 2 in the bars h and being held in
position at their upper ends by entering a slot 3 in the iron support for the
masonry.
The upper portion of the fire chamber a above the side gratings ; l, is made of
suitable refractory material it being supported on suitable projecting ledges n in
the metal plates forming the external covering of the furnace.
The interior bounding surface of this portion of the fire-chamber is in the form
shown in Figures 1 and 2 inclined inwards on all sides as shown at 5 to thus
reduce the pressure of the fuel resting against it and thereby prevent the adhesion
of the clicker material thereto, and the aggregation or formation of a mass of
clinkers thereon.

page_text: The air in passing between the grate bars j and l´at the sides of the furnace as
indicated by the arrows thereon retains the said bars at a much lower temperature
than the side walls of the furnaces as usually constructed, and thus greatly reduces the
tendency of clinker material to form and adhere, while this construction also affords
an opportunity to introduce a poker or similar instrument to dislodge and break
up any clinker which may happen to form, without necessitating the removal of
the fire and bottom grating as in the furnaces of common construction.
The air in passing upward and inward through the side bars; and 1 becomes
heated and entering near the top of the mass of fuel unites with the gaseous
products of the imperfect combustion which has taken place in the main body of
the fuel, thus making the furnace a smoke and gas consumer.
In order to control the amount of air entering at the sides and near the top of
the fuel, suitable dampers p, p², p³, p³, are provided, pivoted at 6 at their upper edges
so as to hang down near the side gratings jl.
These dampers are controlled by suitable mechanism to operate them all simul-
taneously and when swung in as shown in dotted lines, admit the minimum
amount of air which then has to pass longitudinally through the space between
the bars.
When hanging vertical as shown in full lines the air is permitted to pass trans-
versely through the space between the bars throughout their entire length and by
causing the dampers to incline away from grate a still more free passage for the
air is produced.
The movement of the dampers p, ?'', p², p³, to and from the side gratings j l is
accomplished in the following manner.
A rod (see Figures 2 and 3) provided at one end with a handle r² and arranged
to move longitudinally has at its other end an upwardly projecting arm ³ which
engages the damper p to swing it on its pivot 6 toward or from the grating as
the handle is pulled out from or pushed in towards the furnace.
"
The rod is connected at 7 near its handle and with one end of a lever 1
pivoted at 8 and connected at its other end with the damper p' which is thus
given an equal movement with the one p, but in the opposite direction so that
both the dampers p, p¹, approach or recede from their adjacent grating simul-
taneously.
The rod r is also connected at 9 with a three-armed lever & pivoted at 10 to turn
in a horizontal plane.
One arm of the said levers is provided with a vertical bar 8¹ to engage the
damper p and other arm thereof is connected with a rod 8' extended across the
furnace and provided with a vertical bar 8³ to engage the damper p³ and as all
three of the arms of the lever 3 are of equal length the movement of the bars 8' 8'
will be in opposite directions and equal in extent to the movement of the rod r so
that a single movement of the said rod r, as for example in the direction of the
arrow Figure 3 will cause a simultaneous movement of all the dampers towards
their respective side gratings as indicated by the arrows Figure 3 while a move-
inent of the said rod r in the opposite direction will cause all the dampers to swing
away from their respective gratings.
The bottom grate bars may be of any usual construction and as shown in Figures 1
and 2 are provided with notches 11 to engage the bearing bars h which are them-
selves notched as shown at 12 Figure 2 to ensure the proper spacing between the
bars.
The bars are formed of two ribs 13, 14, tied together at intervals by web
pieces 15, the said ribs being far enough apart to leave a space between the
opposite ends of the different series of bars as the ones marked g resting on one
rib 13 and those marked; on the other rib 14 thus preventing the burning of the
said bars.
Instead of using the side grate bars jl shown in Figures 1 and 2 in connection
with the dampers n' m² m³ the hare 21 or 11 7 shown in Figures 9 and 10 may be

page_text: used having their vertical portions resting against the side walls the outline of which
is indicated in these Figures by the dotted lines.
The bars should be and all the grate bars should preferably be made of a
sectional shape similar to that shown at g in Figure 2 thus leaving narrow longitudinal
passages between the said bars and the wall behind them for the passage of the air
as indicated by the arrows:-
The grate bars are provided with a slot 16 at their upper end to engage a flange
or projection 17 which is provided therefor on the supporting ledge n, and the said
bars are supported at their lower ends on a suitable bearing bar u against which
the bars also rest.
When desired to remove the fire from furnaces of this kind of usual construction it
is customary to remove a sufficient number of grate bars from the bottom to allow
of the passage of the fuel.
In my improved furnace this is preferably done by removing the side bars j or
or their ends being suitably bevelled as shown at 20 to enable them to be
readily removed.
The said bars are first pushed inward at their upper ends towards the furnace
after which by slightly raising them their lower ends may be disengaged from the
bearing bars h.
Studs 25 may be used on the grate-bars to insure the proper spacing thereof.
In the modification illustrated in 'Figures 4, 5, and 7 the grate bars g¹ g² of the
floor grating are provided with perforated lugs g³ near their extremities, through
which are inserted rods, fs, by which the said grate bars are held together, the
rods f being supported in notches 30 formed in the upper portion of projecting
wings on the main bearing bar h¹ extended across the middle of the furnace the
said wings forming the support for one end of said grate bars and enabling them all
to be turned upon the said rods ƒ² as a hinge.
The other end of the grate bars g in the rear portion of the furnace is supported
on a bearing bar as there generally-will-be-no-necessity for moving these grate
bars.
One or more of the grate bars g¹ in the front portion of the furnace extend forward
beyond the end of the rest of the grate bars as shown at 31, and are supported
by suitable links or hooks to which access can be had through small doors in the
front of the ash pit to enable the said hooks to be disengaged from the said grate-
bars and thus allow the whole front portion of the grate bars g' to swing down to
the position shown in dotted lines Figure 4 to permit the fuel to fall into the ash
pit.
A sufficient number of the bars g' are supported on the hooks is to properly
sustain the weight of the fuel above, and the rest of the bars receive their support
from these through the rod f' which thus performs the function of a bearing bar.
If desired the bars g' at the rear of the furnace may be supported similarly to
those at the front, but this will not usually be advantageous.
The side dampers are in this construction dispensed with and the vertical bars 1³
are made tapering, being thicker at the top than at the bottom so that the air spaces
35 between them are broader at the bottom than at the top and a gradually decreasing
amount of air is admitted towards the top of the fire.
As shown in Figure 4 the side walls m³ of the furnace above the vertical grate
bars are made of refractory material and provided with small perforations 36 for
the admission of air through them into the fire, the said perforated passages being
connected with an air space 37 left between the said refractory material and the
masonry of the furnace, in continuation of the space 38 behind the vertical grate
bars the said space 37 decreasing in width from its bottom to its top.
In Figures 5, 6, 7 and 8 above the vertical grating 6 in place of the refractory
lining shown in the other Figuros, is a water back w supported in the masonry of
the furnace, it having an inlet tube 40 for cold water at one end and an outlet
tube 41 at the other end, the water being caused to traverse the entire length of the
water back.

page_text: One of these tubes will usually be connected with a boiler located above the
furnace and heated by the products of combustion escaping therefrom, such arrange-
ment being now common in works for smelting and treating ores, the steam
generated in the said boilers being employed for actuating the machinery of the
works.
The feed water for the boilers may pass through the water back w on its
way to the boiler, or the pipes 40, 41, may be connected with the boiler and
properly arranged to insure circulation in the said water-back.
In Figure 6 the water back is shown as consisting of a series of pipes, spaces 42,
being left between the said pipes for the admission of air to the furnace and with
this construction the water back may be extended down to the horizontal or floor
grating, the upright grating being dispensed with, and air spaces 43, would then
be left behind the pipes, between them and the masonry of the furnace, and the
spaces between the pipes would be made narrower in the upper part of the furnaces
to admit a gradually decreasing supply of air towards the top of the fire as
described in connection with the upright gratings of Figures 4 and 5.
In some instances it will be desirable to combine the water-back and vertical
grating as shown in Figure 7, a series of pipes connecting an upper chamber w
surrounding the upper portion of the fire chamber with a lower chamber w² located
at or near the edge of the floor grating.
In this construction the said pipes will be preferably larger at their upper
than at their lower end to control the admission of air in a similar manner to the
tapering grate bars shown in Figure 4.
The chamber w Figure 5 has its inner face next the fuel curved or inclined
outward from the bottom to the top so that the air entering along its lower edge
will have to be diffused through the body of fuel lying against the said chamber
instead of passing by the edge thereof.
Having now described and particularly set forth the nature of the said Invention
and the manner of carrying the same into effect I would have it understood that
what I claim is :-
1. In a furnace, the fuel supporting grating, and the fire chamber having its side
walls inclined inward and upward from the edges of the said grating to reduce the
pressure of the fuel against the side walls, and thereby prevent the adhesion of
clinker material thereto, substantially as and for the purpose set forth.
2. In a furnace the upwardly extending gratings at the sides thereof and side
dampers to control the draught or flow of air through the said gratings, as and for
the
purpose described.
3. In a furnace, provided with upwardly extended side gratings, side dampers to
control the draught through the said gratings, and damper operating mechanism to
move all the said dampers simultaneously, substantially as described.
4. In a furnace grate the bearing bar having two ribs each to support the ends
of adjoining sections of grate bars, and provided with notches to insure the proper
spacing of the said bars, combined with grate bars having notches to engage and
be held in place by the said notched ribs substantially as described.
5. In a furnace, the removable side bars bevelled at their ends to enable them
to be readily removed from their supports, substantially as described.
6. In a furnace the combination of the bottom or floor grating, with upright
gratings, the bars of which are tapered from end to end in their thickness measured
parallel with tho walls of the furnace that they constitute to afford a variable
amount of space for the passage of air between them; as and for the purpose set
forth.
7. In a furnace, the grating consisting of a series of bars, connected together to
form a continuous grating and strung or mounted at one end upon a rod pivoted
and supported on a suitable bearing bar, combined with a removable support for
the other end of the said bars whereby the entire connected grating may be
permitted to turn on the pivoted rod to remove the fire or fuel from the furnace,
substantially as described.

page_text: 8. In a furnace the following elements in combination, the bottom or floor grate,
the upright gratings on all sides thereof; the perforated refractory lining above the
said upright gratings; and a continuous air passage behind the said upright grating
and refractory lining, substantially as described.
9. The main bearing bar provided with notched wings, and a series of grate bars
with perforated lugs and rods passed therethrough, one rod being supported in the
said wings, and sustaining one end of the said bars combined with a removable
hook or support for the other end thereof, substantially as described.
10. In a furnace the combination with the floor or bottom grating and vertical
gratings extended upward therefrom, of a water back surrounding the fire chamber
above the said vertical gratings, substantially as and for the purpose described.
11. In a furnace the combination with the bottom or floor grating, of a water
back consisting of a series of tubes surrounding or living the wall of the furnace at
the sides of the said grating and provided with air spaces between them, gradually
diminishing in size towards the upper part of the furnace substantially as
described.
12. The combination with the bottom or floor grating, of the water back con-
sisting of a series of vertical tubes surrounding the furnace and a continuous
chamber connected with the upper ends thereof, spaces being left behind and
between the said pipes for the admission of air to the fuel, substantially as and for
the purpose described.
In witness whereof I the said William Morgan-Brown have hereunto set
my hand and seal this fifth day of August in the year of our Lord One
thousand eight hundred and eighty two.