IMPROVE. MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN THE CONSTRUCTION AND LINING OF REVOLVING FURNACES, AND IN APPARATUS CONNECTED THEREWITH.
Year: 1873

page_text: LETTERS PATENT to Thomas Russell Crampton, of No. 4, Victoria
Street, in the City of Westminster, for the Invention of "IMPROVE.
MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN THE CONSTRUCTION
AND LINING OF REVOLVING FURNACES, AND IN APPARATUS CONNECTED
THEREWITH.
"
Sealed the 6th January 1874, and dated the 12th November 1873.
PROVISIONAL SPECIFICATION left by the said Thomas Russell
Crampton at the Office of the Commissioners of Patents, with his
Petition, on the 12th November 1873.
I, THOMAS RUSSELL CRAMPTON, of No. 4, Victoria Street, in the City
of Westminster, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN THE CON-
STRUCTION AND LINING OF REVOLVING FURNACES, AND IN APPARATUS CONNECTED
THEREWITH," to be as follows :-
These improvements relate partly to a new and improved mode of
constructing and arranging revolving furnaces which are heated by the
combustion of powdered fuel mixed with air,

page_text: My improved furnaces will be found suitable for being used as
puddling furnaces and also as heating furnaces for reheating iron and
steel, or they may be used for making wrought iron and steel direct
from cast iron or from iron ores, or for other purposes.
My present improvements are in part based upon those respectively
described in the Specifications of my former Patents, dated December
3rd, 1869, and March 28th, 1872.
In the Specification of the former are described various modifications
of fixed furnaces, in that of the latter are described various modifications
of revolving furnaces.
My present improvements consist chiefly in so constructing revolving
furnaces heated by powdered fuel and air that a single revolving
chamber may be employed both as a combustion chamber and working
chamber, the air and fuel being injected at the flue or outlet end, thereby
enabling a simpler construction of furnace to be used, and great 1
economy in the use of fuel to be effected; or a revolving combustion
chamber may also be similarly supplied with air and fuel at the outlet
end, and the products be chiefly utilized outside of the combustion
chamber.
]
My improvements also relate to an improved mode of lining and 2
working revolving furnaces so as to make them available for making iron
and steel direct from the ore, and for reheating as well as for puddling
and other purposes, and also to an improved mode of arranging several
furnaces when it is intended to work them together or in relation to
one another.
I make my revolving furnace of any convenient form and line it with
suitable refractory material, and cause it to revolve on rollers or other
bearings; one end is by preference closed and the other end is open and
covered with a movable flue piece connecting the furnace with a
chimney, which flue piece may have an opening covered with a door
sufficiently large to work the furnace without moving the flue piece for
that purpose.
The furnace is heated by a mixture of powdered fuel and air injected
into the flue end either through pipes passing through the centre on
which the flue piece swings, or through adjustable or fixed pipes which
are capable of being removed from the front when the flue piece or door
is moved aside and accession to the furnace is desired.
2

page_text: In some cases also the pipes are arranged so that on the removal of
the flue or door the pipes may be allowed to remain, permitting the air
and fuel to be injected into the furnace when the flue piece or door is
removed.
The air and powdered fuel may be directed on to the material under
treatment, or away from it, as desired; or the furnaces may be made
capable of being removed from the flue piece and the injecting pipes
arranged accordingly. The furnaces are surrounded by a water casing,
as described in my said former Patent, granted to me on the 28th day of
March 1872.
In puddling iron where the furnace is continuously revolved during a
portion of the process, the furnace lining (which when composed of oxide
of iron is reduced during the process, and the cinder formed is drawn off
from time to time at the tap hole provided for the purpose) is as hereto-
fore repaired with fresh oxide. I now propose to use such revolving
furnaces for reheating iron and steel, in which case the furnace is not
revolved during the reheating process; and I repair or renew the lining
chiefly by means of the oxide formed during the reheating process in the
following manner:-The interior surface of the lining I prefer to be
made with any convenient number of flat sides, say four.
When the work requires a dry bottom tap holes or other convenient
outlets are provided at each flat side to enable the liquid oxide to run
out from the furnace as soon as formed from whichever side may happen
to be downwards, which oxide after the material under treatment has
been withdrawn is replaced into the furnace, or so much of it as
required with or without additional oxide, and is allowed to set or cool
on that side of the lining which requires to be repaired, the furnace
being turned so as to bring that side downwards; or to avoid running
off the oxide as quickly as it is formed the furnace may be turned so
as somewhat to incline the bottom and allow the liquid oxide as it is
formed to flow away from the work under treatment.
When a wet bottom is to be used the bed of the furnace may be hori-
zontal, and the liquid oxide allowed to remain in the furnace, and if
necessary new oxide added.

page_text: arched form and repaired with the oxide formed in the furnace, or with
other oxide, in the manner just described. This mode of working a
reheating furnace enables the use of the ordinary fire-bricks commonly
employed to be dispensed with, the lining being kept repaired, partly or
wholly, by the oxide of iron produced in the furnace itself.
Furnaces capable of being revolved, as described, and which are used
for reheating and such like purposes without being revolved during
such operations, whether, heated by means of powdered fuel, or by
gases, or in other ways, may be lined or have their linings repaired or
renoverated, in the manner above described.
I also propose to employ revolving furnaces lined with oxide of iron,
as herein-before described, and heated by powdered fuel and air, or
otherwise heated for making iron and steel direct from the ore.
In cases where a number of revolving furnaces are to be heated by
streams of air and powdered fuel, and are to be supplied with air from
blowing apparatus, I range the furnaces radially to and around a central
point at which is erected the apparatus for grinding the fuel to powder,
and also an air reservoir into which air is forced by suitable forcing
apparatus. The furnaces are placed with their open ends outwards, and
the pipes for introducing the streams of air mixed with fuel are led to
each furnace from the central air reservoir; and close up to this
reservoir a continuous stream of powdered fuel from a common coal dust
chamber is supplied by feeders to the ends of the pipes. The powdered
fuel mixed with air is thus conveyed directly or nearly so to each furnace
from their respective chambers. The coal may be elevated to the top of
the building and run into the pulverizing apparatus, from which it
descends into a central chamber round which the several feeders are
placed, and in which is a stirrer to force the coal to all the feeders. The
feeders to any of the furnaces can at any time be put out of action, and
the supply of air from the reservoir to the pipes leading to such furnaces
can also be simultaneously regulated or cut off.
In some cases the coal may be pulverized in other positions and con-
veyed by screws or other means to the central coal chamber.
Revolving furnaces heated by air and powdered fuel introduced at the
exit end of the furnace may be provided with suitable apertures or
spaces for the admission of the air and fuel between the revolving
chamber and apparatus in which the heat is to be utilized; such furnaces

page_text: may thus be used for heating steam boilers or for other purposes, the
heated gases from the revolving furnace being led away by flues or other
channels to wherever the heat is to be utilized.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Russell Crampton in the Great Seal
Patent Office on the 12th May 1874.
:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
RUSSELL CRAMPTON, of No. 4, Victoria Street, in the City of West-
minster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of November, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Thomas Russell Crampton,
Her special license that I, the said Thomas Russell Crampton, my
executors, administrators, and assigns, or such others as I, the said
Thomas Russell Crampton, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and.
lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN THE MANUFACTURE OF IRON
AND STEEL, AND IN THE CONSTRUCTION AND LINING OF REVOLVING Furnaces, and
IN APPARATUS CONNECTED THEREWITH,' upon the condition (amongst others)
that I, the said Thomas Russell Crampton, my executors or admini-
strators; by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to.
be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
"
NOW KNOW VE that T the said Thomas Russell Crampton do

page_text: the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, that is to say :-
These improvements relate partly to a new and improved mode of
constructing and arranging revolving furnaces which are heated by the
combustion of powdered fuel mixed with air.
My improved furnaces will be found suitable for being used as
puddling furnaces, and also as heating furnaces for reheating iron
and steel; or they may be used for making wrought iron and puddled
steel direct from cast iron, or from iron ores, or for making cast steel,
or for melting or other purposes.
My present improvements are in part based upon those respectively
described in the Specifications of my former Patents, dated December 3rd,
1869, and March 28th, 1872.
In the Specification of the former are described various modifications
of fixed furnaces, and the manner by which powdered fuel and air
are injected at one end into such furnaces, the products of combustion
returning at or near the same end. In that of the latter are described
various modifications of revolving furnaces and the mode of cooling
them.
By my present improvements I so construct revolving furnaces that
a single revolving chamber may form both the gas-producing chamber,
the combustion chamber, and the working or utilizing chamber, the
chamber being lined with a refractory substance suitable to the material
under treatment, and being heated by powdered fuel and air. The
fuel and air is injected at the flue or outlet end, passes through the
opening into the furnace, and the products of combustion return through
the same opening into the chimney, thereby enabling a simple con-
struction of furnace to be used, and great economy in the use of fuel
to be effected. Or a revolving combustion chamber may also be similarly
supplied with air and fuel at the outlet end, and the products be utilized
outside of the combustion chamber.
I also form the lining and work revolving furnaces so as to make
them available for reheating as well as for puddling and other purposes.
When it is intended to work several furnaces together, or in relation
to one another, I combine them and the apparatus for feeding them
into a system, as is herein-after described.

page_text: I make my revolving furnace of any convenient form, and line it
with suitable refractory material, and cause it to revolve by any
ordinary means on rollers or other bearings; one end is by preference
closed, and the other end is open. The fuel enters and the products
of combustion make their exit through this same opening which is
covered with a movable flue piece connecting the furnace with a
chimney, the flue piece may have an opening covered with a door
sufficiently large to work the furnace without moving the flue piece
for that purpose.
The furnace is heated by a mixture of powdered fuel and the pro-
portionate quantity of cold or hot air injected into the flue end at
such a velocity that the streams of fuel and air will reach the further.
end of the chamber and return, thereby allowing ample time for the
generation of gases and their perfect combustion, the velocity also
being such as to prevent the incoming current on entering the furnace
being deflected by the return currents. The entrance is effected either
through a pipe or pipes passing through the centre on which the flue
piece may be caused to swing, or through adjustable or fixed pipes
which are capable of being removed (with or without the flue piece)
from the front of the furnace when the flue piece or door is moved
aside, and access to the furnace is desired.
In some cases also the pipes are arranged so that on the removal of
the flue or door the pipes may be allowed to remain, permitting the
air and fuel to be injected into and keeping hot the furnace when the
flue piece or door is removed. Under ordinary circumstances the lining
of the furnace retains sufficient heat to ignite the fuel after discharging
and recharging the furnace, especially if the fuel contains much volatile
combustible matter, as does ordinary bituminous coal.
The air and powdered fuel conveying pipes are so constructed as to
allow of the fuel and air being directed on to the material under
treatment or away from it as desired; or the furnaces may be made
capable of being removed from the flue piece and the injecting pipes
arranged accordingly. The furnaces are by preference cooled by means
of water in the manner described in the Specification of my said former
Patent granted to me on the 28th day of March 1872.
In puddling iron where the furnace is continuously revolved during a
portion of the process the furnace lining is as heretofore repaired with

page_text: fresh oxide; when such lining is composed of oxide of iron it is reduced
or partly melted during the process, and the liquid formed is drawn off
from time to time at the tap hole provided for the purpose.
I use for
reheating iron or steel such revolving furnaces heated by air and
powdered fuel injected into them through the outlet end as previously
described. In this case the furnace is not revolved during the reheating
process, and I use for repairing and renewing the lining the oxide
formed during the reheating process. The interior surface of the lining
I prefer to be made with any convenient number of flat sides, say three
or five.
When the work requires a dry bottom tap holes or other convenient
outlets are provided at each flat side to enable the liquid oxide to run
out from the furnace as soon as formed from whichever side may happen
to be downward, the bottom being inclined slightly towards the tap
holes or outlets for that purpose. This oxide after the material under
treatment has been withdrawn is replaced in a melted or solid state in
the furnace, or so much of it as is required, with or without additional
oxide, and is allowed to set or cool on that side of the lining which
requires to be repaired, the furnace being turned so as to bring that side
downwards. The side thus repaired and levelled forms the sole or bed
of the furnace to receive upon it the piles of pieces of iron or steel next
to be reheated. The furnace having been charged fuel and air duly
proportioned are blown in until the heat required for rolling, hammering,
or otherwise working the metal is obtained; or if it is desired not to
run off from the furnace, the liquid oxide as quickly as it is formed, the
furnace may be turned so as somewhat to incline the bottom and allow
the liquid oxide as it is formed to flow away from the work under
treatment and accumulate on the lower side, and the oxide is tapped off
when required.
When a liquid oxide bottom is to be used the bed of the furnace may
be horizontal, and the liquid oxide formed in the furnace allowed to
remain (or so much of it as is required), and if necessary new oxide
added. After the material under treatment has been withdrawn the
other beds or sides are repaired by turning the furnace round, so as to
bring the bed or side required to be repaired into the lowest position.
The liquid oxide is then introduced and allowed to cool on them, either
alone or with the addition of fresh oxide, care being taken that the
bottom is as smooth and even as possible. Thus by allowing the melted

page_text: oxide of iron to flow to a level surface in the chamber and then to set I
obtain a flat bed to receive the metal to be reheated, and in this way
and by turning the vessel between the heats I renew any part of the
lining which requires repair.
When it is desired to add fresh oxide to that already in the furnace
the fresh oxide may be introduced in a solid state if there be sufficient
melted oxide in the furnace to run over it to form a level surface.
In some cases solid oxide may be thrown in, and if necessary be
wholly or partly melted so as to form a level bed.
In order to have a supply of melted oxide when required I store the
oxide tapped out of the furnace in a large vessel, in which it will keep
melted for a long time beneath the solid shell which forms on the
surface.
In some cases one flat side only may be used on which the material to
be reheated is placed, the other portion of the interior of the furnace
being of an arched or other convenient form, and the furnace is turned,
and the lining is then repaired with the oxide formed in the furnace or
with other oxide in the manner just described. This new mode of
treating and working a reheating furnace enables the use of the ordinary
fire-bricks commonly employed to be dispensed with, the lining being
kept repaired partly or wholly by renewing it as often as may be
necessary with oxide of iron produced from the oxidisation of the iron
or steel under treatment and from the remelting of the oxide lining in
the furnace itself. The surplus oxide which is not required for the
lining may be used for puddling purposes, for which it is peculiarly
applicable, it being free from the impurities caused by the melting and
mixing of the argillaceous or silicious matters of which ordinary furnaces
are chiefly constructed.
Furnaces capable of being revolved as described, and which are used
for reheating, while stationary may by treating them in the manner
above described have their linings repaired or renewed whether they be
heated by means of powdered fuel or by gases generated in other
chambers or in other ways.
I also employ revolving furnaces lined with oxide of iron, as herein-
before described, or lined with other suitable materials, such furnaces
being heated by powdered fuel and air in the manner herein-before

page_text: mentioned for making iron and puddled steel direct from the ore by any
of the well known methods of manufacture.
In cases where a number of revolving furnaces are to be heated by
streams of air and powdered fuel, and are to be supplied with air from
blowing apparatus, I range the furnaces or pipes radially to and around
a central or common point, at or near which is or may be erected the
apparatus for grinding the fuel to powder; and also an air reservoir,
into which air is forced by suitable forcing apparatus. The furnaces are
placed with their open ends outwards. The pipes for introducing the
streams of air mixed with fuel are led to each furnace from the central
or common air reservoir, and close up to this reservoir a continuous
stream of powdered fuel from a common chamber is supplied by feeders
to the ends of the pipes, and injected into them by means of the air
according to the injecting process commonly adopted by me and well
known.
In some cases the fuel may be forced by screw or other apparatus into
the air-injecting pipe, and so be introduced into the furnace, or other
means of introduction may be employed.
The powdered fuel and air are conveyed directly or nearly so to each
furnace from the central or common chambers. The fuel may be
elevated to the top of the building and run into the pulverizing apparatus,
from which it descends into a central or common chamber, around or
upon which the several feeders are placed, and in which is a stirrer or
stirrers to force the coal to all the feeders. The quantity of fuel fed
can be regulated at will, or the supply of fuel to any one of the furnaces
can be stopped by putting the feeding machine out of action, and the
supply of air from the reservoir to the pipes leading to such furnaces
can also be simultaneously regulated or cut off.
The fuel may be pulverized in other positions and conveyed by screws
or other means to the central fuel chamber, or in some cases the common
air and fuel chambers may be placed away from the centre of the
furnaces.
Revolving furnaces lined with bricks or other suitable materials
heated by air and powdered fuel introduced at or near the exit end of
the furnace may be provided with suitable apertures or spaces for the
admission of the air and fuel between the revolving chamber and
apparatus in which the heat is to be utilized, or the air and fuel may be

page_text: caused to pass through a space before ariving at the revolving portion,
the products returning through such space. Furnaces so constructed
and worked may be used for heating steam boilers or for other purposes,
the heated gases from the revolving furnace being led away by flues or
other channels to the place where the heat is to be utilized.
Det Figures 1, 3, 4, 5, 0.
A is a single revolving chamber which is caused to rotate by any
well-known means, and so that the speed can be adjusted to any velocity
up to, say 15 revolutions per minute; B is the refractory lining;
C, C, the wheels on which it revolves; D, the movable flue piece lined
with suitable refractory material capable of being removed when access
to the furnace is required; d, d, are screws for keeping the flue against
the furnace; other convenient means may be employed for that purpose.
E shews by dotted lines the flue piece removed, but the same may be
allowed to remain in front of the furnace if a sufficiently large door is
provided at its end similar to an ordinary furnace door; F is a long
opening in the movable flue piece through which the air and fuel are
injected; f, f, are several small doors for covering any portion of the
opening F when required; G, the adjustable injecting pipe (one or more
may be used) the end of which can be raised or lowered for conveying
the fuel and air into the furnace in such direction as may be desired;
g, g, are several divisions in the bend for the purpose of preventing the
fuel and air separating through the fuel running alone on the outside of
the bend.
H shews by dotted lines the adjustable pipe removed from the front
of the furnace when access to it is required.
Any other mode of arranging the pipe or pipes for injection of fuel
and air, as for instance the following, may be adopted,—
1. See Figure 11. By passing the injecting pipe through the centre
on which the flue piece is made to swing, the pipe may move with the
flue piece or may remain in front of the furnace for the purpose of
injecting fuel and air as before described.
2. See Figure 12. By placing the injecting pipe over the furnace but
not in the centre on which the flue piece is made to swing, the pipe.

page_text: to be moved with or without the flue piece, for the purposes as before
described.
3. See Figure 13. By fixing a portion of the injecting pipe upon the
flue piece the remaining portion to be fixed upon the chimney or
otherwise, the pipes butt together and form a joint when the flue piece 5
is in its place, this joint being broken when the flue piece is removed.
4. See Figure 14. By making a portion of the injecting pipe movable
by a hinge or by other means, the pipe to be entirely independent of the
flue piece and fixed to the chimney or otherwise.
5. See Figure 15. By injecting the air and fuel direct into the 1
chamber without passing through the flue piece by providing a suitable
hole on the outside of the flue piece, through which the injecting pipe.
can be introduced.
.
Any other mode of removing the injecting pipe from the front of the
furnace when access to the same is required may be adopted. 8 (see ]
Figure 4) is a feeder for pulverised fuel, the fuel falls from the feeder
in regulated quantities into the induced current produced by the
injection of a jet of air V into a larger pipe G, through which it is
conveyed to the furnace; I is the opening or passage through
which the products of combustion are conveyed from the movable 2
flue piece into the chimney, or to where they may be required to be
utilized.
The manner in which the water is introduced into the casing is as
follows: In rear of the furnace a double-way cock L is fixed revolving
with the furnace, the shell M of the cock being a fixture. Through an a
opening m in this cock the water pipe passes into the pipe O, and is
discharged at or near the flue end at P. The water returns through the
casing and makes its exit through the other opening n in the cock
similar to that described in the previous Patent granted to me 28th
March 1872.
It is important that any air entering the casing of the furnace,
together with the water, should be discharged without requiring any
special attention to this point. For this purpose I have devised the
following arrangement:-I employ a radial outlet pipe R carried to the
extreme inside of the casing at T which revolves with the furnace chamber
and carries off the heated water and also provides an escape for the air.

page_text: The escape of air can take place each time that by the rotation of the
furnace the pipe R is brought into an upright position. During the
time the furnace remains stationary or at any time when convenient,
this air may be discharged through small cocks placed on the outside of
the furnace; J, is a ring attached to the furnace casing; J¹, is a ring
attached to the flue piece casing, which rings form a wearing joint
between the furnace and flue piece. The inside of these rings is in
contact with the water circulating through the respective casings; these
rings may be removed and renewed when necessary; or I use an
independent hollow wearing ring in two pieces, attached to or connected
with the revolving furnace casing (see Figures 2 and 2*), and water is
made to circulate through this [ring. For this purpose I carry the
pipe O before mentioned out of the casing and connect the end of it
with the two half rings before mentioned at v, v. The water after
passing through the half rings passes into the water casing at x, x, and
through it and the pipe R out at the opening n in the cock L as before
described. This ring may be in one or more pieces, the water com-
munications being suitably arranged, regulating handles may be placed
near the flue piece communicating with the engine driving the rotary
furnace and the gear for regulating or stopping entirely the supply of
air and fuel.
Figures 7 and 8 shew the application of rotary combustion chambers
as above described in which the fuel is injected from the open end, the
products of combustion returning through the same opening and passing
into a passage or chamber, there to be utilized. To elucidate this
application of revolving chambers, they are shewn here applied to steam
boilers.
Figure 7 shews a mode of injecting the fuel and air by means of the
pipe or pipes L introduced at or near the mouth of the revolving com-
bustion chamber J, through a suitable opening or openings in the.
boiler K, the direction of the currents being shewn by arrows.
Figure 8 shews another mode of injecting fuel and air by means of a
pipe or pipes O at some distance from the mouth of the revolving
combustion chamber M, the streams of air and fuel traversing the
space
P in the boiler N. After passing into and out of the revolving
chamber, they return through the same space P on their passage to the
chimney, the direction of the currents being shewn by arrows.

page_text: Figures 9 and 10 shew an arrangement in which a number of
revolving furnaces are placed round a central fuel and air reservoir,
from which they are supplied with fuel and air by means of injecting
pipes.
A, A, are the furnaces, say eight in number; B, B, the movable t
flues; C, C, the chimneys; E, is the air reservoir supplied with air by a
fan F ; H is the fuel reservoir supplied with fuel by the screw I.
From the air reservoir a number of jets of air regulated by valves, one
or more to each furnace, issue into one or more larger pipes D, D, and
the fuel is taken in at the point of injection, where it is delivered in 1
measured quantities by the fuel feeding machines G, G, the long.
pipes D, D, conveying the mixture to the furnaces.
The pipes D, D, at or near the furnaces are constructed so that by a
joint d they can be removed from the front of the furnace when
necessary, while a second joint & allows the nozzle of the pipe to be 1
lowered or raised at the will of the operator.
Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood, that I do
not claim generally the well known separate parts employed by me in
the construction of my improved furnace, such for instance as the 2
apparatus for injecting air or fuel or the movable flue piece, as such
parts were well known at the date of these Letters Patent, and it is
only when combined and arranged as herein described that they form
parts of my present Invention; I claim,-
1. The construction and use of furnaces having a single revolving 2
chamber heated by the injection of fuel and air and serving as a gas
producing chamber, also as a combustion chamber, and also as a working
or utilizing chamber, substantially as herein described.
2. The improved method of conducting the process of re-heating iron
or steel to prepare it for being rolled, hammered, or otherwise worked,
by using a furnace having a working chamber which is stationary while
the re-heating is going on, but is capable [of being revolved, and by
lining that chamber with oxide of iron, and by turning the chamber
partly round between the heats, so as to allow of the repair of the lining
substantially as herein described.
3

page_text: 3. The construction and use of furnaces with a revolving gas pro-
ducing and combustion chamber combined with a steam boiler or other
apparatus in which the heat is utilized, fuel and air being injected into
the combustion chamber at one end, and the products issuing from the
chamber at the same end and passing into the heating space of the
boiler or other apparatus, substantially as described.
4. The arrangements for supplying a number of furnaces with air
and powdered fuel from a common source, substantially as described.
5. The combination with the revolving chamber of a furnace of a
separate hollow wearing ring fixed to and revolving with the chamber,
and having water circulating through it, substantially as described.
6. The construction and use of furnaces having revolving chambers
and flue pieces provided with wearing rings, constructed substantially as
described in respect to Figure 5 of the Drawings.
7. The combination of a rotating furnace chamber with a pipe or
pipes through which air and fuel are injected into such chamber in such
manner that the said air and fuel on entering the rotating chamber is
caused to pass through the flue by which the products of combustion
escape from the rotating chamber, substantially as described.
In witness whereof, I, the said Thomas Russell Crampton, have
hereunto set my hand and seal, this Twelfth day of May, in
the year of our Lord One thousand eight hundred and seventy-
four.