IMPROVEMENTS IN AND RELATING TO STEAM GENERATORS AND THEIR FURNACES"
Year: 1883

page_text: LETTERS PATENT to Henry Clay Bull, of Liverpool, in the County of
Lancaster for an Invention of "IMPROVEMENTS IN AND RELATING TO STEAM
GENERATORS AND THEIR FURNACES"
PROVISIONAL SPECIFICATION left by the said Henry Clay Bull at the
Office of the Commissioners of Patents on the 23rd August 1883.
HENRY CLAY BULL, of Liverpool, in the County of Lancaster
IN AND RELATING TO STEAM GENERATORS AND THEIR FURNACES
"IMPROVEMENTS
"
My Invention relates to certain improvements in boilers for generating steam
and in furnaces therefor, which furnaces are so constructed and fitted with
apparatus as to form combined gas producers and combustion chambers and are
worked on what is known as the "gas firing" principle
A boiler and furnace of the vertical type constructed according to my Invention'
and for gas firing, consists of three vessels arranged and connected together in the
following manner, namely, the vessels are arranged side by side; the central vessel
is cylindrical with semi spherical ends and the side vessels are of cylindrical form
with a portion of their shells cut away and join onto the shell of the central vessel,
the sides of which come within the cut away portion of the outside cylinders,
suitable passages as hereinafter described are formed in the shell of the central
vessel to afford communication between the central and side vessels for circulation.
The side vessels are tube filled having top and botton tube plates. An intermediate
diaphragm is provided near the top of each vessel, so as to isolate the upper portion
of the vessels and so form these portions into superheaters.
The vessels are
provided with dome tops which form uptakes to the chimney. The side vessels
are mounted over combustion chambers and an arrangement of gas producing
furnaces provided with hopper charging doors, removeable fire bars and closed
ashpits. Each side vessel has two or more furnaces according to size separated by
divisions. The upper portion of the gas producing furnace forms the combustion
chamber. Air is admitted to the combustion chambers to support combustion of
the gases generated in the furnace through pipes, or passages, which are formed in
bridges formed on the sides of the central vessel, the bridges being placed in the
1

page_text: combustion chamber of the side vessels. The gas producing furnaces are supplied
with a forced draught of steam and air under the closed grate by a suitable device
such as a Korting blower, blowing into the closed ashpit where a pressure is
maintained of about equal to 2" mercury.
The central vessel has semi spherical ends, the lower end projects below the
botton tube plates of the side vessels and the upper end projects above the upper
tube plates.
Circulating pipes and passages are provided as follows: the side vessels have
communications with the central vessel at their lower sides and at their bottoms
by pipes leading from the bridges before spoken of, and also have communication
just below the diaphragm tube plate, this communication being two and one half
times the capacity of the lower communication The central vessel is water filled
to a point about the centre of the top circulating passage, the upper portion of the
vessel being steam space and communicating with the superheaters of the side
vessels.
By the construction of a boiler as above described, I obtain a boiler of great
efficiency occupying a small space, also having a good circulation, thus preventing
the burning of tube plates and giving a great economy in the consumption of fuel.
In constructing a boiler and fire box, or furnace of the locomotive type according
to my Invention and for gas firing, I provide the fire box with an inclined water
bridge. The end of the bridge is swelled and provided with a central air passage
and a circulating tube between the bridge and the crown of the fire box. The
central air passage opens out through the shell of the boiler on each side and in
front. This central passage is provided with openings for admitting air into the
fire box. The fire box is divided below the bridge by a water division which is
swelled and provided with a central air passage, thus dividing the fire box into two
chambers, which are worked as gas producers and are provided with hopper
charging doors with a removeable arrangement of fire bars a closed ashpit and are
supplied with a forced draught of steam and air under the grate by a suitable
device such as a Korting blower, blowing into the closed ashpit at a pressure of
about 2" mercury. The closing is effected by doors placed in front of the furnace,
and the furnace bars are so positioned as to be easily withdrawn for clinkering, or
for other purposes. In operation the fire is lighted and made as in an ordinary
locomotive furnace until steam is made, when the forced draught is applied and the
thickness of the fuel on the grate is increased, thus, generating gas and working the
furnace as a gas producer and burning the gas thus generated above the bridge
which forms the combustion chamber, the combustion being made complete by the
natural inrush of air, mixing with gas as it comes through the air passages above
specified.
By the construction of a boiler and furnace of the locomotive type as above
described, I obtain a boiler worked on the gas firing principle, the gas producer
and combustion chamber being contained in the boiler and a good circulation is
produced at the same time the prevention of the burning of the furnace crown is
obtained.
In constructing a tubular boiler or furnace, or fire box of the marine type,
according to my Invention and for gas firing, I form the shell of the boiler a
cylinder, the furnace being contained in the boiler and having vertical sides similar
to a locomotive fire box, the boiler being semi cylindrical above the fire box. The
following is a description of one end of a double ended boiler, of say 16 feet
diameter having a central chamber, or uptake. The furnace, or fire box is
provided with a water bridge swelled at the end, where it is fitted with a central
air passage for supplying air into the combustion chamber. The central air
passige opens out through the shell of the boiler on each side. The fire box is
divided into four furnaces by water divisions which form communications with the
front and back of the fire box and with the bridge. These divisions of which there
are three are swelled at their upper portions in a similar manner to the bridge for
receiving central air passages for supplying air to the combustion chamber and

page_text: open out through the shell of the boiler to the front and are joined to the air
passage in the bridge by T joints. The top of the divisions are level with the top
of the bridge, the space above the bridge, namely between the level of the bridge
and the divisions and the crown of the furnace forming the combustion chamber.
The ashpit is made closed by doors and divided by three partitions, thus making
four closed spaces one under each furnace and are fitted with Korting blowers.
Each furnace is provided with a hopper charging door and an arrangement of fire
bars easy of removal. The fire tubes are in two nests; the lower nest extends from
the back plate of the furnace, combustion chamber and the central chamber, or
uptake, and the upper nest extends from the central chamber or uptake to the
front plate of the boiler, which is provided with an uptake of ordinary construction
and leads to a chimney common to both ends of the boiler.
Circulation is obtained through tubes placed between the bridge and the crown
of the furnace; being similar to that described in the description of the vertical
and locomotive types of boilers according to this Invention.
In operation the fire is lighted and made as an ordinary marine boiler furnace,
until steam is made when the forced draught is applied and the thickness of the
fuel on the grate is increased, thus generating gas and working the furnace, as gas
producers, and burning the gas generated above the bridge in the combustion
chamber, the combustion being made complete by the natural inrush of air mixing
with gas, as it comes through the air passages above specified.
By the construction of a boiler and furnace of the marine type as above described,
I obtain a boiler worked on the gas firing principle the gas producer and combustion
chamber being contained in the boiler occupying small space and having a large
amount of heating surface and giving a great economy in the consumption of fuel,
also having a good circulation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Clay Bull in the Patent Office on the 21st February 1884.
HENRY CLAY BULL, of Liverpool, in the County of Lancaster "IMPROVEMENTS
IN AND RELATING TO STEAM GENERATORS AND THEIR FURNACES
"
My Invention relates to certain improvements in boilers for generating steam
and in furnaces therefor, which furnaces are so constructed, and fitted with
apparatus as to form combined gas producers and combustion chambers and are
worked on what is known as the "gas firing" principle.
A boiler and furnace of the vertical type constructed according to my Invention
and for gas firing consists of three vessels arranged and connected together in the
following manner, namely the vessels are arranged side by side; the central vessel
is cylindrical and the side vessels are of cylindrical form and join onto the shell of
the central vessel, the sides of which come within a portion of the outside vessels,
suitable passages as hereinafter described are formed in the shell of the central
vessel to afford communication between the central and sido vessels for circulation.
The side vessels are tube filled having top and bottom tube plates. An intermedinte
diaphragm is provideded near the top of each vessel, so as to isolate the upper
portion of the vessels and so form these portions into superheaters. The vessels are
provided with dome tops which form uptakes to the chimney. The side vessels
are mounted over combustion chambers and an arrangement of gas producing
furnaces provided with hopper charging doors removeable fire bars and closed.
ashpits. The upper portion of the gas producing furnace forms the combustion
chainber. Air is admitted to the combustion chambers to support combustion of
the gases generated in the furnace through pipes, or passages, which are formed in
bridges, the bridges being placed in the combustion chamber of the side vessels.
The gas producing furnaces are supplied with a forced draught of steam and air
under the closed grate by a suitable device such as a Korting blower, blowing into
the closed ashpit where a pressure is maintained of about equal to 2" mercury.
Circulating pipes and passages are provided as follows: the side vessels have
communications with the central vessel at their lower sides, and also have
communication just below the diaphragm tube plate. The central vessel is water
filled to a point about the centre of the top circulating passage, the upper portion
of the vessel being steam space and communicating with the superheaters of the
side vessels.
By the construction of a boiler as above described I obtain a boiler of great
efficiency, occupying a small space, also having a good circulation, thus preventing
the burning of tube plates and giving a great economy in the consumption of fuel.
In constructing a boiler and fire box, or furnace of the locomotive type according
to my Invention and for gas firing I provide the fire box with a water bridge.
The bridge is provided with a central air passage. The central air passage opens
out through the shell of the boiler on each side. This central passage is provided
with openings for admitting air into the fire box. The fire box is divided below
the bridge by a water division, thus dividing the fire box into two chambers,
which are worked as gas producers and are provided with hopper charging doors
with a removeable arrangement of firo bars, a closed, ashpit, and are supplied with
a forced draught of steam and air under the grate. by a suitable device such as a
Korting Blower" blowing into the closed ashpit at a pressure of about 2" mercury.
The closing is effected by doors placed in front of the furnace and the furnace bars
are so positioned as to be easily withrawn for clinkering, or other purposes. In
operation the fire is lighted and made as in an ordinary locomotive furnace until

page_text: steam is made when the forced draught is applied and the thickness of the fuel on
the grate is increased, thus generating gas and working the furnace as a gas
producer and burning the gas thus generated above the bridge in the combustion
chamber the combustion being made complete by the natural inrush of air mixing
with gas as it comes through the air passages above specified.
By the construction of a boiler and furnace of the locomotive type, as above
described, I obtain a boiler worked on the gas firing principle, the gas producer and .
combustion chamber being contained in the boiler and a good circulation is
produced at the same time the prevention of the burning of the furnace crown is
obtained.
In constructing a tubular boiler and furnace, or fire box of the marine type
according to my Invention and for gas firing, I form the shell of the boiler a
cylinder, the furnace being contained in the boiler and having vertical sides
similar to a locomotive fire box the boiler being semi cylindrical above the fire box,
The following is a description of one end of a double ended boiler, of say 16 feet
diameter, having a central chamber, or uptake. The furnace, or fire box is
provided with a water bridge, fitted with a central air passage for supplying air
into the combustion chamber. The central air passage opens out through the shell.
of the boiler on each side. The fire box is divided into furnaces by water divisions,,
which form communications with the front and back of the fire box and with the
bridge; the space above the bridge, namely between the level of the bridge and the
divisions, and the crown of the furnace, forming the combustion chamber. The
ashpit is made closed by doors and divided by partitions, thus making closed spaces
one under each furnace and they are fitted with "Korting Blowers." Each furnace
is provided with a hopper charging door and an arrangement of fire bars easy of
removal The fire bars are in two nests; the lower nest extends from the back
plate of the furnace, combustion chamber and the central chamber, or uptake and
the upper nest extends from the central chamber, or uptake to the front plate of
the boiler, which is provided with an uptake of ordinary construction and leads to
a chimney common to both ends of the boiler.
In operation the fire is lighted and made as in an ordinary marine boiler
furnace until steam is made, when the forced draught is applied and the thickness
of the fuel on the grate is increased, thus generating gas and working the furnace,
as gas producers and burning the gas generated above the bridge in the combustion
chamber, the combustion being made complete by the natural inrush of air mixing
with gas as it comes through the air passages above specified:
By the construction of a boiler and furnace of the marine type as above
described, I obtain a boiler worked on the gas firing principle, the gas producer
and combustion chamber being contained in the boiler occupying small space and
having a large amount of heating surface and giving a great economy in the
consumption of fuel also having a good circulation.
The beforegoing being the nature of this Invention, I would have it understood
that it consists in certain improvements in boilers for generating. steam and in
furnaces therefor, which furnaces are fitted with apparatus so as to form combined
gas producers and combustion chambers, in which the coal is partially burnt under
a forced draught of air and steam and converted to gas, consisting chiefly of
carbonic oxide, the steam of the forced draught is converted to hydrogen and the
carbonic oxide and hydrogen together are ignited above the coal in the producers
by a secondary supply of free air through water jacketted supply pipes ;-thus the
boilers are worked on what is known as the gas firing principle a thorough
circulation is ensured and provision is made for precipitating and intercepting
solid matters, and the Invention is applicable to various types of boilers for
example to vertical boilers, boilers of the locomotive type, boilers of the marine
type, boilers of the Lancashire type.
To enable the Invention to be clearly understood, I will proceed to describe
more in detail how the same may be carried out into practical effect and for that

page_text: provements VIL DICUNT trenerators WHLE ENGOT PIETNUCER.
purpose I have hereunto attached nine sheets of Drawings which are inarked with
figures and letters of reference corresponding with those in the following
explanation, like letters and figures being used to denote like, or corresponding
parts throughout the views.
Figure 1 is an elevation partly in section of a boiler and furnace of the vertical
type constructed according to this Invention.
Figure 1 is a section through the line A. B. Figure 1.
Figure 1B is a plan of Figure 1.
Figuro 1º is an elevation partly in section of an alternative arrangement of
Figure 1.
Figure 1 is a section through the line A. B. Figure 1°.
Figure 1 is a section through the line C. D. Figure 1°.
Figure 1is a plan of Figure 1°
Figure 1 is a sectional elevation of a modification of Figure 1º.
Figure 1 is a plan of Figure 1°
Figure 2 is a sectional elevation of a boiler of the vertical type with this
Invention applied thereto.
Figure 2 is a side elevation of Figure 2.
Figure 2B is a section through A. B. Figure 2.
Figure 2 is a section through C. D. Figure 2.
Figure 3.is a sectional elevation ot a boiler and furnace of the locomotive type
constructed according to this Invention
Figure 34 is an end view partly in section of the back of the fire box and ashpit
Figure 3.
Figure 3 is a sectional elevation through A. B. Figure 3.
Figure 3º is a sectional elevation through C. D. Figure 3.
Figure 3 is an end view of Figure. 3.
Figure 4 is a sectional elevation of a boiler and furnace of the locomotive type,
constructed according to this Invention, being a modification of Figure 3.
Figure 4 is a section through A. B. Figure 4.
Figure 4 is an end view of Figure 4.
Figure
40 is a section through C. D. Figure 4.
Figure 4 is an outside elevation of Figure 4.
Figure 5 is an elevation partly in section of a double ended boiler and furnaces
of the marine type constructed according to this Invention.
Figure 5 is an end view of Figure 5 shown partly in section through the
line A. B. Figure 5.
Figure 6 is a sectional elevation of a boiler and furnace of the Lancashire type
according to this Invention.
Figure 64 is an end view of Figure 6 shown partly in section through the
line A. B. Figure 6.
Figure 6B is a plan of Figure 6 shown partly in section through the line C. D.
Figure 6.
Figure 6° is an elevation partly in section of the water circulating tubes and
air pipe Figure 6.
Figure CD is a side elevation of Figure 6° being taken in section through the
line A. B. Figure 6º.
The Drawings above described show examples of various. known types of boiler
and each of the examples show the application of the Improvements, which constitute
this Invention to such boilers as bereinunder described.
Reference to Figures 1, 1ª 1B
"
A boiler and furnace of the vertical type constructed according to this Invention
and for gas firing consists of three vessels A. B B' arranged constructed and
connected together in the following manner namely, the vessels are arranged side.
by side. The central vessel A is cylindrical with a semi spherical top and a flat 5
bottom supported by the vortical stays A'. The sido vessels B B₁ are each of the

page_text: same construction, namely they are of cylindrical form and butt onto and are
connected to the central vessel A, as shown in the Drawings. Passages C D E are
formed on the side of each vessel, as hereafter described to afford communication
between the central vessel A and the side vessels B B¹ for circulation of water and
for steam connection. The side vessels B B¹ are tube filled between the tube plates
F G which are positioned as shown. An intermediate diaphragm plate H is
provided near the top of each vessel B B¹ so as to isolate the upper portion of each
vessel at I and so form these portions I into superheaters. These vessels are
provided with dome tops J, which form uptakes to the chimney. The tube nest of
each side vessel B B¹ is mounted over a combustion chamber K and a gas producing
furnace L. Both the combustion chamber K. the furnace L and its ashpit O are-
water jacketted and water bottomed as shown. Each side vessel is provided with a
hopper M for charging the furnace L with fuel. These hoppers M are each.
provided with a door M' for filling in the fuel and a door, or valve M² for allowing
the fuel from the hopper M. to pass into the furnace L. The furnaces L are
provided with removeable fire bars L' and closed ashpit doors L². Each combustion
chamber K is provided with a water jacketted air supply bridge pipe N, which
passes right through the combustion chambers K and the side vessels B B¹ as
shown. The water jackets of the bridge pipes N being in communication with the
water space of the side vessels. B B¹ and a pipe N' being provided which
communicates between the water jacket of the bridge pipe N and the centre of the
vessel. Each bridge pipe N is provided with air nozzles N¹ which open from the
bridge pipe N into the combustion chamber K. The function of these bridge pipes
N is to admit air through the nozzles N¹ to support combustion of the gases (which
are given off from the gas producing furnace L) in the combustion chamber K.
The gas producing furnaces L are supplied with. a forced draught of steam and air
by a suitable device such as a Korting Blower P, which is arranged to blow
through the pipes P1 P2 into the closed ashpits O and maintain a pressure of about
equal to two inches mercury, valves P³ being provided so as to shut off the forced-
draught of either furnace L when required.
i
Circulating pipes and passages being communications between the vessels.
A and B and A and B are provided as follows. The side vessels B B communicate
with the central vessel A through the passages. C, which passages C are opposite
the tube plates F and through the passages D, which passages D are just below the
diaphragms H. The central vessel A is water filled to a point about the centre of
the communicating passage D where the steam is liberated. The upper portion of
the vessel A being steam space and communicating through the pipe. E' and
passages E with the superheaters I of the side vessels B B¹ from whence the steam.
is drawn for use.
By the construction of a vertical boiler and furnace as above described, there is
obtained a boiler of great efficiency, occupying a small space and having a thorough
circulation of the water which flows down to the bottom of the vessel A and up and
over the lip, or plate R³ and through the passages C down the passage between the
angle irons a (which passage is protected by the brick lining R¹) to the bottom of
the boiler and up round the sides of the producer L into the vessels B B₁ and
through the passages D into the vessel A into the bottom of which solid matters.
from the water precipitate and collect. Circulation of the water through the
jacket of the bridge pipe N is also ensured by the pipe N2, which communicates
with the centre of each vessel BB'
Reference to Figures 1° 1° 1° and 1 it will be seen that the bridge pipe N
shown in Figure 1 is dispensed with and the nozzles N₁ are placed in the shell of
the boiler and round the combustion chamber K. In lieu of the bridge pipe N
there is provided a central pipe N2 which is swelled out in the combustion chamber K
so as to cause a co-mingling of the gases with the air through the nozzles N¹. The
circulation of the water is as follows: the cooler water in the central chamber A
flows through the pipes, or passages. C and up. the hot sides of the producer:

page_text: furnaces Land combustion chambers K and up the central pipe N' above which is
provided a deflecting cone ba deflector plate R being also provided above the tube
plate F. These deflectors b and R cause the current of water to sweep over the
tube plate F and thereby provent the deposit of solid matter thereon. The water
then passes up and through the pipes, or passages D into the central chamber A in
which it descends and in its descent meets the coned hood R and rapidly sweeps
past the lower edge thereof and then rises slowly up round the lower edge into the
down pipe R and thence into the pipes, or passages C.
The result of the rapid
passage of the water past and over the hood R and the slow rise up and into the
down pipe R is; that all solid matter is precipitated into the bottom of the
chamber A which is away from all heat and from whence the deposit is withdrawn.
or "blown off" Cleaning doors e are provided round the boiler to provide access
to the tube plate F.
In the modification shown at Figures 1° and 1" in which Figure 1º is a sectional
elevation and Figure 1" a sectional plan of a portion of the vessel A it will be seen
that instead of the central down pipe R³ and hood R*, I substitute the four down
pipes R and hoods R².
Reference to Figures 2 24 2B 20
In its main characterists this boiler is what is known as a vertical donkey
boiler fitted with "Field" tubes. The gas producing furnace L cliarging hopper M
combustion chamber K air bridge tube N, blower P and their accessory parts as
described in reference to Figure 1. are here shown in combination with this donkey
boiler.
Reference to Figures 3, 34, 3º, 3º and 3D
A boiler and furnace of the locomotive type constructed according to this
Invention and for gas firing consists in fitting the fire box so as to form it into a
gas producer of like nature to that shown at Figure 1. The fire box is provided
with a bridge Q, and a central water diaphragm which divides the fire box into the
two gas producers L L and the combustion chamber K which are provided with
feeding hoppers M air bridge pipe N removeable fire bars L' closed ashpit doors L'
and blowing apparatus P and makes the fire box similar to the fire box of the
boiler shown at Figure 1. To ensure the circulation of the water round the fire box
the back of the gas producers Lat R¹ are lined with fire bricks and a plate Ris
provided so as to induce a downflow of water. The crown of the fire box being the
hottest. point the water will naturally be induced to circulate down from the
plate R. A baffle plate R³ is also provided to arrest and collect the sediment and
a plate R is provided to cause the water to sweep all sediment from the furnace
crown.
By the construction of a boiler and furnace of the locomotive, type as above
described there is obtained a boiler worked on the gas firing principle, the gas
producers and combustion chamber being.contained in the boiler.
Reference to Figures 4. 4A 4B 40 4D
This example illustrates this Invention as applied to a boiler of the locomotive
type, particularly suited as a boiler for torpedo boats. In construction the fire box
resembles the fire box of the boiler shown at Figure 3 namely it is provided with
a bridge Q, and a central water diaphragm R which divides the fire box into two
gas producers L L and the combustion chamber K which are provided with the
feeding hoppers M M air bridge pipe N removeable fire bars L' closed ashpit
doors L blowing apparatus P which makes the fire box similar to the fire box of
the boiler shown at Figures 3, 2, and 1.
Reference to Figures 5 5^
This example illustrates this Invention as applied to a double ended marine boiler
of return tubular nature. In construction the fire box resembles the fire box
shown at Figures 3 and 4, namely it is provided with a bridge Q and two water
diaphragms RR, which divide the fire box into three gas producers L L L and
the combustion chamber K, which are provided with the feeding hoppers M M M

page_text: air bridge pipe N.removeable fire bars L' closed ashpit doors L2 blowing apparatus P,
thus making the fire box similar to the fire box of the boiler shown at Figures 4,
3, 2. 1. In this arrangement it will be seen that by duplicating the fire box, thus
constructed and by combining such fire boxes with a return tubular arrangement
as shown at Figure 5 there is obtained a double ended boiler having very large
heating surface and suitable for marine purposes and having perfect circulation and
thorough combustion of fuel.
Reference to Figures 6, 6A 6B 6° 6º.*
This example illustrates this Invention as applied to a double flued Lancashire
Boiler. In construction the fire box is built of fire brick in a metal casing at the
end of the boiler and resembles the fire box shown at Figure 3, except that it is
not water jacketted. It is provided with a bridge Q, and a diaphragm R which
divides the fire box into two gas producers L L and the combustion chamber K
which are provided with the feeding hoppers M M air bridge pipe N removeable
fire bars L closed ashpit doors L2 blowing apparatus P, thus making the fire box
similar to the fire box of the boiler shown at Figure 3. In this case to supply the
water jacket of the bridge pipe N and to provide for the circulation of the water
in the boiler the bridge pipe Ñ is connected to the boiler at the top by the pipes N°
and at the bottom by the pipe N³ as shown in detail at Figures 6° 6º. For
clearness of explanation the air nozzles are not shown in these figures, but will be
seen on reference to the other Figures of this Drawing.
In working the system of firing, which is comprised in this Invention the fire
is lighted in the producers L of the boilers above described as in an ordinary fire
place and so maintained until steam is generated, when the ashpit doors are closed
and the forced draught of steam and air is applied, the thickness of the fuel on the
grate bars is increased to the necessary depth and the furnace is worked as a gas
producing furnace, this Invention giving a secondary combustion over the fuel in
the combustion chamber K which is supported by the natural inrush of free air
through the bridge pipe N and nozzles Ni.
Having now described this Invention, it must be understood that there is not
claimed as this Invention the use of gas produced by the partial combustion of coal
by a forced draught of steam and air for firing steam generators, as the means of
producing and applying such gas is well known.
What is claimed as this Invention is
First in a boiler for generating steam, the combination of vessels comprising a
steam generator and superheater a combined gas producer and combustion chamber
and a water vessel and steam chest, connected, arranged, constructed and operating
as herein described and shown in Figures 1 14 1B and in 1° 1° 1 1 and in 1G 1❝
of the Drawings hereto annexed.
Second In a steam generator, the combination of a vessel, or vessels B and a
water vessel, or vessels. A being connected and provided with water circulating
ducts CD and plates, or devices R2 R3 whereby circulation of the water is induced
and obtained and sediment is precipitated and intercepted in the water vessel, or
vessels A substantially as herein set forth in reference to Figures 1 1ª 1B and to
1° 1 1 1 and to 1° and 1% of the Drawings hereto annexed.
Third In a steam generator, forming the furnace thereof into a combined gas
producer and combustion chamber, the combustion of the gas generated being
supported by a secondary supply of air directly over the gas producing fire,
substantially as herein described and shown in the Drawings bereto annexed.
Fourth The combination in a steam generator, of a lining R¹ and deflector
plates R R whereby a circulation of water is induced and the surfaces of the
combustion chamber are swept by such induced circulation substantially as and for
the purposes specified.
Fifth The combination in a steam generator of a plate, or device R² and a plate,
or device R whereby the solid matters in the water are intercepted and
precipitated substantially as and for the purposes specified

page_text: Sixth In a combined gas producer and combustion chamber of the type herein
described the combination of an air supply pipe having a water jacket connected
to the water space of the boiler substantially as and for the purposes specified.
In Witness whereof, I, the said. Henry Clay Bull have hereunto set iny hand
and seal. this eighteenth day of February in the year of our Lord one thousand
eight hundred and eighty four.
HENRY, CLAY. BULL (L.S.)