IMPROVE- MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN APPARATUS EMPLOYED IN SUCH MANUFACTURES
Year: 1865

page_text: LETTERS PATENT to Henry Bessemer, of Queen Street Place, New
Cannon Street, in the City of London, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN APPARATUS EMPLOYED
IN SUCH MANUFACTURES,"
Sealed the 27th April 1866, and dated the 3rd November 1865.
PROVISIONAL SPECIFICATION left by the said Henry Bessemer at the
Office of the Commissioners of Patents, with bis Petition, on the 3rd
November 186.
I, HENRY BESSEMER, of Queen Street Place, New Cannon Street, in the
City of London, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN APPARATUS
EMPLOYED IN SUCH MANUFACTURES," to be as follows:-
My present Invention relates, firstly to the treatment and purifying of
molten iron after it leaves the blast furnace and before solidification takes
place, and also in the treatment and purifying of pig-iron and cast-iron
scraps. Either of these qualities or kinds of iron may be refined in a'
finery or "running-in furnace," or in a "running-out furnace" in the
ordinary manner, by blasts of air and the employment of mill scale or
other fluxes in the most approved manner, using good or purified coke as
fuel. The metal so treated may be carried in ladles or other vessels
Price 8d 1

page_text: mounted on wheels to the furnaces, where it is to be further treated; or
it may be conveyed there in gutters or channels while still retaining the
fluid state, or the finery metal may be run into flat plates as commonly
practised. Either of the three distinctive qualities of metal herein firstly
named may, however, be employed in the second or puddling process
without having undergone the "finery process" above described; but
when crude molten iron from the blast furnace is to be puddled or treated
in a manner analagous to puddling for the purposes of my present
Invention, I prefer to convey it to the puddling furnace in ladles mounted
on wheels, so that it may be conveyed there in a fluid state; but when
pig iron, cast scrap iron, or finers' plate metal is to be treated in the
puddling furnace I prefer to melt the metal in a cupola furnace prior to
running it into the puddling furnace. For this purpose I prefer to employ
what is known as Ireland's upper tuyere furnace; or, if it be preferred,
the pig iron, the cast-iron scrap, or the refined plate metal may be employed
in an unfused state, and be melted in the puddling furnace where they are
to be further treated. The puddling furnace employed for the purposes
of my Invention I prefer to make of much larger dimensions than those
usually employed, and I also prefer to heat the same with gaseous fuel,
although a good flaming coal may be employed in lieu thereof. This
furnace is to be mounted on axes placed either above or below the hearth
of the furnace (but I prefer them below), so that an oscillating motion
may be given to it by means of cranks or eccentrics; the furnace may also
be provided with means for giving it a further motion on its axes than is
given to it during the process, in order more easily to discharge the
contents therefrom; when desired, the rods or rabbles, if any be employed
to further agitate and divide the metal, may be introduced through suitable
openings in the sides of the furnace, and their outer ends be so supported
on a joint or pin that the motion of the furnace will make them stir or
move the metal in a similar manner to that effected by the movement of
the rabble to and fro in ordinary fixed puddling furnaces; the rods or
rabbles employed may also be more or less operated upon and worked by
manual power if desired, or so altered in position by mechanical means as
to further assist in turning over and working or puddling the charge of
metal; the bottom or hearth of the furnace may be prepared after the
manner employed in ordinary puddling furnaces, and the lining of such
furnace be prepaired or "fettled" from time to time with red or titaniferous
iron ore,
"bull dog," or other suitable material. The bottom may be
convex, concave, or flat, with the angles rounded out so as to prevent

page_text: accumulations there of the materials under operation. Any desirable or
ordinary flux may be employed, such as "mill scale," red ore, common
salt, or oxide of manganese, as in the ordinary puddling process.
The
pipes which convey cold or heated air and gases to either or both ends of
the furnace and the chimney, or the lower part thereof, may be made to
oscillate with the furnace, and in those cases where solid fuel is con-
sumed the fire-grate (if one be used) or the fire-chamber into which a
blast of air is conveyed for keeping up combustion when no grate is
employed may be made to oscillate with the furnace, or the fire-grate or
chamber and also the chimney may be fixed and the puddling furnace or
chamber be made to oscillate between them. And here I would observe
that I prefer to place such improved puddling furnace at such a level that
the fluid metal to be operated upon therein may be run into it from the
furnaces wherein such metal is melted; it may be found preferable, when
first agitating or puddling the fluid metal in such furnace, to make the
furnace move through a less space and at a less speed than when the
metal assumes a less fluid condition by rendering the eccentric or crank
pin which gives motion to the furnace adjustable; the use of the rods or
rabbles may also be in the first place omitted; when however solid metal,
pigs, or plate metal is treated in such furnace the motion of the furnace
need not take place until the metal has run or has fallen down in a fluid
or granular or semi-fluid condition. There are three conditions under
which the impure metal treated in such furnace may be withdrawn there-
from for the purpose of being converted into cast steel; viz., in a fluid or
weak fluid state, in a pasty or more or less concrete or granular form, or
in the state of puddle balls; the metal in either of these stages may be
mixed with molten grey iron and be converted in the usual way by what
is generally known as the Bessemer iron or steel process, or the metal
so puddled or partially puddled may be allowed to fall out of the puddling
furnace into water, or be allowed to cool gradually and be afterwards put
into a ladle or furnace or into the converting vessel with molten iron, or it
may before such conversion be first recarbonized in the manner herein-
after described; but when it is intended to recarbonize the puddled metal
prior to its conversion into steel or malleable iron by the Bessemer process,
the metal from the puddling furnace may be allowed to fall in between a
pair of rolls (kept cool with water) placed horizontally so that the puddled
metal may be more or less separated from the adhering slags and solidified
and formed into flat cakes or other convenient forms, so as to offer a large
surface to the action of the gases in the carbonizing furnace; it will be.

page_text: obvious that such rolled or flattened pieces may be piled and formed into
bars or plates in the manufacture of ordinary wrought iron, and also that
the puddling furnace herein-before described may be employed in the manu-
facture of puddled iron of the ordinary kind, and that the balling up of the
metal may in such cases be effected more or less by manual labour, either
through the ends of the furnace when moved beyond its ordinary position
or throngh suitable openings or doors formed in the side of the furnace.
I have shewn how crude or impure iron may be in part purified and refined
by puddling or partially puddling such metal, but in such purifying process
it looses nearly the whole of its carbon and passes more or less into the
solid state, and in that condition is not suitable for final purification by the
Bessemer process unless it be mixed with a molten carburet of iron; I
therefore in most cases prefer to submit such puddled or partially puddled
metal, whether in the granulated state or more or less in the condition of
puddle balls, or in the flattened or squeezed condition to the action of car-
bonic oxide gas at a very high temperature, whereby the metal will absorb
enough carbon to form it into "white iron," and so carbonized it may be
readily melted and be used alone or in combination with rich No. 1 grey
pig iron (or other iron), and be converted into steel or into malleable iron
by the Bessemer process.
It will be found useful to put a small quantity
of good grey pig iron along with the puddled metal into the recarbonizing
furnace, and any steel scraps or broken ladle skulls or other waste pieces of
Bessemer iron or steel may be so treated in the carbonizing furnace alone
or mixed with other iron. For the purpose of carbonizing the puddled metal
or steel scraps, I prefer to use a small blast furnace or a tall cupola furnace
in which a good pure coke or prepared peat or other fuel as free as possible
from sulphur is employed, or a furnace similar to a reverberatory furnace
may be employed, in which carbonic oxide is consumed in lieu of solid
fuel, and which gas may be employed in such excess as will both carbonize
and afterwards fuse the puddled metal.. I also prefer to employ carbonic
oxide gas
in a highly heated state in addition to solid fuel to assist in
carbonizing and fusing the metal when employing the small blast furnace
or cupola furnace before referred to.
Although I prefer to employ the puddling apparatus herein-after
described for the purpose of purifying iron and rendering it more suitable
for conversion into malleable iron or steel by the Bessemer process, it will
nevertheless be obvious that crude or impure iron may for such purposes
be treated by the ordinary process of puddling by hand labor, or by any
mechanical means of puddling that may be found to answer the desired

page_text: object, without departing from the nature of my Invention in so far as
relates to the production of an improved quality of iron for conversion into
malleable iron or steel by the Bessemer process.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Bessemer in the Great Seal Patent Office on
the 3rd May 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
BESSEMER, of Queen Street Place, Cannon Street West, in the City of London,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of November, in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Henry Bessemer, Her special licence that I, the
said Henry Bessemer, my executors, administrators, and assigns, or such
others as I, the said Henry Bessemer, 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 APPARATUS EMPLOYED IN SUCH MANUFACTURES," upon the condition (amongst
others) that I, the said Henry Bessemer, my executors or administrators,
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 YE, that I, the said Henry, Bessemer, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
My present Invention relates, firstly, to the treatment and purifying of
molten iron after it leaves the blast furnace and before solidification takes
place, and also in the treatment and purifying of pig-irou and cast-iron
scraps. Either of these qualities or kinds of iron may be refined in a finery

page_text: "
or running-in furnace," or in a "running-out furnace," in the ordinary
manner by blasts of air and the employment of mill scale or other fluxes
in the most approved manuer, using good or purified coke as fuel. The
metal so treated may be carried in ladles or other vessels mounted on
wheels to the furnaces where it is to be further treated, or it may be
conveyed there in gutters or channels while still retaining the fluid state,
or the finery metal may be run into flat plates as commonly practised.
Either of the three distinctive qualities or conditions of metal herein
firstly named, that is, molten iron after it leaves the blast furnace and
before solidification takes place, and pig-iron and cast-iron scraps may,
however, be employed in the second or puddling process without having
undergone the ordinary "finery process" above described or referred to,
but when crude molten iron from the blast furnace is to be puddled or
treated in a manner analogous to puddling for the purposes of my present
Invention, I prefer to convey it to the puddling furnace in ladles mounted
on wheels, so that it may be conveyed there in a fluid state. But when
pig iron, cast scrap iron, or finers' plate metal is to be treated in the
puddling furnace, I prefer to melt the metal in a cupola furnace prior to
running it into the puddling furnace. For this purpose I prefer to
employ what is known as "Ireland's upper tuyere furnace," and which is a
modification of the ordinary ironfounders' cupola furnace, having several
tuyeres at a higher level than those generally employed in such furnaces,
and is thereby rendered capable of fusing iron both rapidly and econo-
mically; or if it be preferred, the pig iron, the cast-iron scrap, or the
refined plate metal may be employed in an unfused state and be melted
in the puddling furnace, where they are to be further treated. The
puddling furnace employed for the purposes of my invention I prefer to
make of much larger dimensions than those usually employed, and I also
prefer to heat the same with gaseous fuel although a good flaming coal
may be employed in lieu thereof. This furnace is to be mounted on axes
placed either above or below the hearth of the furnace (but I prefer them
below), so that an oscillating motion may be given to it by means of cranks
or eccentrics; the furnace may also be provided with means for giving it
a further motion on its axes than is given to it during the process, in order
more easily to discharge the contents therefrom when desired. The rods
or rabbles, if any be employed to further agitate and divide the metal, may
be introduced through suitable openings in the sides of the furnace, and
their outer ends be so supported on a joint or pin that the motion of the
furnace will make them stir or move the metal in a similar manner to

page_text: that effected by the movement of the rabble to and fro in ordinary fixed
puddling furnaces; the rods or rabbles employed may also be more or less
operated upon and worked by manual power, if desired, or so altered in
position by mechanical means as to further assist in turning over and
working or puddling the charge of metal; but although I have described
how the metal under treatnient may be worked by rods or "rabbles"
during the puddling process, I desire it to be understood that their
employment is by no means indispensable in that operation, since the violent
agitation of the metal caused by the reciprocating motion of the puddling
chamber when moved quickly will in most cases be found sufficient for
the purposes of my Invention. The bottom or hearth of the furnace may
be prepared after the manner employed in ordinary puddling furnaces,
and the lining of such furnace be repaired or "fettled" from time to time
with red ore, titaniferous iron ore, "bull dog," or other suitable material,
in a manner well understood; the bottom may be couvex, concave, or flat,
with the angles rounded out so as to prevent accumulations there of the
materials under operation; any desirable or ordinary flux may be employed,
such as "mill scale," red ore, common salt, chloride of calcium, oxide of
manganese, or metallic manganese alloyed with a carburet of iron or other
matters employed in the ordinary puddling process. The pipes which
convey cold or heated air and gases to either or both ends of the furnace,
and the chimney, or the lower part thereof, may be made to oscillate
with the puddling furnace; or the fire-grate or fire-chamber, and also the
chimney when they are employed, may be fixed, and the puddling furnace
or chamber be made to oscillate between them. And in order that the
general plan and construction of the puddling furnace which I prefer to
employ for the purposes of my Invention may be fully understood, I have
shown the same in several Figures on the annexed sheet of Drawings, where
Figure 1 is a side elevatiou, Figure 2 an end elevation, Figure 3 a vertical
longitudinal section, Figure 4 a cross section, and Figure 5 a horizontal
section on the line A, B, of Figure 3. The puddling chamber a is made
by preference of stout "boiler-plate," and is lined on the inside with
fire-bricks, fire-stone, "ganister," "bull dog," or other refractory material,
such as now employed for similar purposes. The interior cavity thus
formed is bounded on all sides more or less by curved lines, so as to
present no corners or acute internal angles in which the matters under
treatment may solidify or fill up; beneath the floor plates 6 two strong
pedestals care secured to the masonry or foundation; the pedestals c
support the axis d on which the whole apparatus oscillates; in the central

page_text: part of this axis a strong piece of iron framing e is firmly keyed, the lower
part of the frame supporting the counterbalance weight f, and the upper
end of it supporting the central part of the puddling chamber a; at each
end of the axis d large flanges are formed, to which are bolted the plate
iron tubular passages g, g; these passages are lined with suitably formed
fire-lumps or other refractory materials, and communicate at their lower
ends with the fixed passages h, h, by means of a circular joint, on the
outside of which rings or hoops are fitted so as to keep an air-tight joint
(or nearly so) between the fixed passages h, h, and the oscillating passages
9. g. These passages 9, 9, are continued upwards through the ends of
the puddling chamber at g', and are then directed at an angle downward,
as shown at g, g; each of the passages g and h, before described, are for
the purpose of conveying gas or gaseous products into or out of the
puddling chamber a, and there are also other passages of a like character
i and k, for the conveyance of air into the puddling chamber, and which
last-named passages need not be lined with fire-brick or other similar
material unless very highly heated air is to be passed through them.
In employing carbonic oxide gas mixed more or less with carburetted
hydrogen such as is produced by the slow combustion of coal, coke, or
other fuel in a close chamber, and generally employed in ",
gas furnaces,"
I desire it to be understood that the said gases may for the purposes of my
Invention be employed either at the temperature which they acquire in the
process of their formation, or such gases may be highly heated by passing
them through hot iron pipes after the manner of heating "hot blast," and
the atmospheric air used for their combustion may also be used at the
ordinary temperature, or it may be heated in any convenient manner prior
to its being conveyed into the puddling chamber. I also desire it to be
understood that the air and gases for combustion may be all admitted at
one end of the puddling chamber, and the products of combustion and
other vapours arising from the materials under operation may be alloved
to pass off at the other end throughout the whole time of operating on a
charge of metal, or the gases may be made to enter and flow off from each
end of the puddling chamber alternately at short intervals, as may be found
most suitable for keeping up a regular and powerful heat in the puddling
chamber; but in lieu of heating the air or gases in the mode described it
will be understood that the heating of the said air and gases before under-
going combustion in my improved puddling furnace may be effected by the
method now employed, and well known as "Siemen's regenerative gas
furnaces," and to which mode of heating air and gases I lay no claim.

page_text: Whenever the puddling chamber a requires to be relined it may be un-
bolted from the upper flange of the frame e, and at the same time
the flanges m which connect the passages formed at each end of the pud-
dling chamber with that portion of the said passages that are attached to
the axis d may also be unbolted, when the puddling chamber may be
removed by a crane from the other part of the apparatus and placed on a
truck for conveyance to a convenient place for repairs; in the meantime a
duplicate chamber may be bolted on to the apparatus and the operations
resumed. The motion of the apparatus may be produced by a crank (not
shown in the Drawings), but which may be attached to one end of the con-
necting rod n, so that the rotation of the crank shaft will produce a constant
reciprocating motion of the apparatus on its axis d, the counterbalance
weight serving to render the oscillating motion of the apparatus more
regular and uniform; the crank actuating these puddling machines should
have upon it a fly wheel the better to regulate its motion. In working this
apparatus I prefer first to thoroughly heat the interior of the chamber a by
the admission of gases by the passages g and h at one end of the apparatus,
and also the admission of air through one of the passages i and k, the air
ascending to the highest part of the apparatus will find an exit through a
long slit or a series of nozzles at *; the air I prefer to be under slight
pressure, such as a fan blast, so that it may carry the gases from the passage
g2 down upon the hearth, and along it to the exit passages at the other end.
The metal, if in a fluid state, may then be admitted through a small open-
ing p in the upper side of the puddling chamber, but if the metal to be
operated on be in form of pig, plate, or scrap metal it may be introduced
at the door or opening on one side of the hearth, where also any fluxes
or matters intended to act chemically on the impure metal may be intro-
duced. The opening r may then be stopped up securely by a luting of
fire-clay on a lump of fire-brick, a bar of iron or other convenient con-
trivance being employed for keeping it firmly in place. As soon as the
metal is in a fused state the apparatus may be put in motion, the effect of
which will be to powerfully agitate the metal, which will leap up the curved
sides of the chamber and fall over in a more or less divided state among
the fluxes or purifying agents at every alternate motion of the apparatus;
meanwhile the combustion of gases may go on and keep up the tempera-
ture of the metal to the desired extent; in this application of gaseous
great facility is afforded for rendering the flame oxydizing or nonoxydizing
as may be desired, by regulating the admission of air and gas by a suitable
valve in the pipes or passages through which they pass to the furnace.
fuel

page_text: Thus when it is desired to act chemically on the fused carburet of iron for
a lengthened period by means of the fluxes present the quantity of air
admittted should be less than is required for the perfect combustion of the
gas, whereby a nonoxydizing flame will be produced and the metal under
treatment will retain for a lengthened period the greater part of the carbon
originally combined therewith; and on the other hand, a more rapid decar-
bonization of the metal may be effected when desired by admitting air in
excess of the quantity required for the combustion of the gas supplied to
the furnace. The employment of gas as fuel also admits of a rapid or a
gradual change of temperature at the will of the operator, and is therefore
well adapted for the process of puddling where changes of temperature
are required, as is well understood.
In the Sheet of Drawings hereunto annexed I have shown in Figure 5
the sides of the puddling chamber a made straight for some distance and
curved at each end, but the withdrawal or running out of the charge of
metal from the door or opening will be facilitated if the entire sides of
the puddling chamber be curved as shown at Figure 6, which is a horizontal
section of a puddling chamber on a smaller scale. It is probable that the
different manner in which some kinds of iron behave in the puddling
process may render other changes of form desirable in order to operate
upon them to the greatest advantage; for example, the bottom of the
chamber may be made flat or nearly so, as shown in cross section at Figure
7, or it may be raised more or less in the centre, as shown in cross section
at Figure 8, so likewise the oval form of section shown in Figure 4 may
be made to approach more to the circular form without departing from the
principle on which the puddling chamber is made to operate by its back-
ward and forward motion on the metal; and here I would observe that I
prefer to place such improved puddling furnace at such a level that the
fluid metal to be operated upon therein may be run into it from the furnaces
wherein such metal is melted. For this purpose several such puddling
furnaces should be placed as near to the tap hole of the blast furnace as
convenient, so that a common gutter may serve for their supply, but in
those cases where it would be inconvenient to place the puddling furnaces
sufficiently near to the blast furnace to receive their supply of fluid iron by
means of a gutter, the metal may be conveyed to them in ladles or vessels
mounted on wheels, and be thus moved on rails to a greater distance from
the balst furnace; in such cases I should prefer to make a valvular opening
in the bottom of the ladles similar to that generally employed in the
Bessemer process, but which modes of conveying the metal is not claimed.

page_text: by me as part of the Invention desired to be secured by these Letters
Patent.
In carrying my improved mode of puddling or purifying iron into
practical operation it may be found preferable when first agitating or
puddling the fluid metal in such furnace to make the furnace move through
a less space and at a less speed than when the metal assumes a less fluid
condition by rendering the eccentric or crank pin which gives motion to
the furnace adjustable, by sliding in a dovetailed joint in a manner well
understood and employed in planing, slotting, and other machines, for the
purpose of regulating the length of stroke of the reciprocating parts of
such machines, or the alteration of the length of stroke of the puddling
machine may be effected in any other convenient way. It will be under-
stood that the use of the rods or rabbles may also be omitted in the first
place or entirely omitted; when however solid metal pigs or plate metal is
treated in such furnace the motion of the furnace need not take place
until the metal has run or has fallen down in a fluid or granular or semi-
fluid condition. There are two conditions under which the impure metal
treated in such furnace may be withdrawn therefrom for the purpose of
being converted into cast steel, viz., in a pasty or more or less concrete or
granular form, or in the state of puddle balls; the metal in either of these
stages or conditions may be mixed with molten grey iron, and be converted
in the usual way by what is generally known as the Bessemer iron or steel
process, or the metal so puddled or partially puddled may be allowed to
fall out of the puddling furnace into water, or be allowed to cool gradually
and be afterwards put into a ladle or furnace or into the converting vessel
with molten iron, or it may before such conversion be first recarbonized in
the manner herein after described; but when it is intended to recarbonize
the puddled metal prior to its conversion into steel or malleable iron by the
Bessemer process, the metal from the puddling furnace may be put into
the recarbonizing furnace in a loose granular state, or in the form of
puddle balls more or less coherent; it is preferred to break up the metal
more or less at that stage of the puddling process when it forms itself into
balls, so as to facilitate the removal of them in small pieces through the
opening of the puddling chamber; one or more openings may also be
made in the ends of the puddling chamber for the purpose of introducing
a bar or hook for dividing the metal when it begins to form into lumps,
such openings being secured by a stopper during the early stages of the
process; or in order to extrude the greater portion of the slags or fluxes
prior to recarbonization the granular or imperfectly balled metal may be

page_text: allowed to fall in between a pair of rolls (kept cool with water).
A pair
of rolls suitable for this purpose is shown in vertical section at Figure 9,
and in plan at Figure 10, on the annexed Sheet of Drawings; the axes
and body of the rolls are cast hollow for the passage of water through
them, suitable stuffing boxes being provided to facilitate the ingress and
egress of the water; other portions of water may also be applied in
jets externally to the lower sides of the rolls as they revolve; one
roll is made with deep end flanges, and the other roll fits in between
them, thus forming a stop at each end, and consequently a cavity or
hopper into which the granular metal and slags are allowed to fall
from the puddling chamber. Instead of bringing these rolls together
with screws in the ordinary manner it will be preferable to force them
together with a weighted lever or other yielding force as adopted in bone
mills and in other cases where rolls are required to compress or crush sub-
stances of irregular hardness or thickness; these rolls are placed horizontally,
so that the puddled metal may be more or less separated from the adhering
slags and solidified and formed into flat cakes or other convenient forme, so
as to offer a large surface to the action of the gases in the carbonizing
furnace; it will be obvious that such rolled or flattened pieces may be
piled and formed into bars or plates in the manufacture of ordinary
wrought iron, and also that the puddling furnace herein-before described
may be employed in the manufacture of puddled iron of the ordinary kind,
and that the balling up of the metal may in such cases be effected more or
less by manual labour, either through the ends of the furnace when moved
beyond its ordinary position or through suitable openings or doors formed
in the side of the furnace. I have shown how crude or impure iron may
be in part purified and refined by puddling or partially puddling such
metal, but in such purifying process it loses nearly the whole of its carbon,
and passes more or less into the solid state, and in that condition is not
suitable for final purification by the Bessemer process unless it be mixed
with a molten carburet of iron. I therefore, in most cases, prefer to submit
such puddled or partially puddled metal, whether in the granulated state
or more or less in the condition of puddle balls, or in the flattened or
squeezed condition, to the action of carbonic oxide gas at a very high
temperature, whereby the metal will absorb enough carbon to form it into
"white iron," and so carbonized it may be readily melted and be used
alone or in combination with rich No. 1 grey pig iron (or other iron) and
be converted into steel or into malleable iron by the Bessemer process; it
will be found useful to put a small quantity of good grey pig iron along

page_text: with the puddled metal into the recarbonizing furnace, and any steel scraps
or broken ladle skulls, or other waste pieces of Bessemer iron or steel, may
be so treated in the carbonizing furnace alone or mixed with other iron
For the purpose of carbonizing the puddled metal or steel scraps, I prefer
to use a small blast furnace or a tall cupola furnace in which a good pure
coke or prepared or other fuel as free as possible from sulphur is employed,
or a furnace similar to a reverberatory furnace may be employed in which
carbonic oxide is consumed in lieu of solid fuel, and which gas may be
employed in such excess as will both carbonize and afterwards fuse the
puddled metal.
I also prefer to employ carbonic oxide gas in a highly
heated state in addition to solid fuel to assist in carbonizing and fusing the
metal when employing the small blast furnace or cupola furnace before
referred to. The gas forced into the blast or cupola furnace, when required
chiefly for carbonizing the metal, should be introduced at a higher level
than the tuyeres which supply blast for the combustion of the coke or
other fuel; but when gas is employed with a view to keep up or increase
the heat of the metal it should be forced downward at an angle on to the
surface of the metal, and in such position that air from the blast tuyeres
may become mixed and combined therewith, so as to produce a powerful
heating flame; the gas, however, by preference being used in such excess
as to prevent oxydation and loss of metal. Although I prefer to employ
the puddling apparatus herein-before described for the purpose of purifying
iron and rendering it more suitable for recarbonization and subsequent
conversion into malleable iron or steel by the Bessemer process, it will
nevertheless be obvious that the crude or impure iron may for such purposes
be treated by the ordinary process of puddling by hand labour, or by any
mechanical means of puddling that may be found to answer the desired
object, and may be then recarbonized in the manner herein-before described
and melted into a carburet of iron without departing from the nature of my
Invention in so far as relates to the production of an improved carburet of
iron for conversion into malleable iron or steel by the Bessemer process.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I am aware that it
has been proposed to act on fluid iron in a puddling furnace, and to transfer
the same whilst still in a fluid state into a converting vessel such as is used
in the Bessemer process; and I mention this in order to state that I make
no claim thereto, and I have found in experiment and practice that such
treatment of fluid iron does not produce a satisfactory result, and that it is
necessary to conduct the process of puddling beyond the fluid state of the

page_text: iron, and to cause it to assume the pasty or granular state in order that the
fluxes may act fully thereon before conveying the puddled or partially
puddled iron into the converting vessel of the Bessemer process.
Firstly, I claim the combined operations of melting in a cupola furnace
finery iron," pig iron, or cast scrap iron, alone or in combination, and the
puddling or partial puddling of such molten metal by mechanical means or
by hand labour, and its conversion (in combination with a grey carburet of
iron) into malleable iron or steel by the Bessemer process.
Secondly, I claim the puddling or partial puddling, as herein described,
of "finery iron," pig iron, or cast scrap iron, and its fusion in or admixture
with molten crude iron or remelted pig iron for the purpose of rendering
the same more suitable for conversion into malleable iron or steel by the
Bessemer process.
Thirdly, I claim puddling or partially puddling iron in an oscillating
puddling chamber heated by gaseous fuel.
Fourthly, I claim the method herein described of conveying gaseous fuel
and atmospheric air to puddling furnaces, and the exit of the products of
combustion therefrom by means of oscillating pipes or passages.
Fifthly, I claim the agitation of molten carburet of iron with suitable
purifying fluxes or matters in an oscillating furnace heated by gaseous
fuel preparatory to the conversion of such carburet of iron (alone or in
combination with another portion of carburet of iron not so treated) into
steel or into malleable iron.
Sixthly, I claim melting by means of gaseous fuel "finery iron," pig
iron, or cast-iron scraps in an oscillating furnace, prior to the purification
of such metal by the action of fluxes thereon.
Seventhly, I claim the pressing or consolidating of granulated or puddled
or partially puddled iron by the action of rolls in the manner herein-before
described.
Eighthly, I claim the employment of the oscillating gas puddling furnace
herein-before described, for the purpose of manufacturing ordinary
puddled or wrought iron.
Ninthly, I claim the recarbonization and fusion of puddled or partially
puddled iron in a cupola or blast furnace, such iron being (either in a
granulated state, or in the condition of puddle balls, or in a more or less
squeezed or compressed state,) and the employment of such fused metal
alone or mixed with other portions of carburet of iron for conversion into
malleable iron or steel by the Bessemer process.
Tenthly, I claim the recarbonization and fusion of puddled or partially

page_text: puddled unwrought iron in a reverberatory gas furnace, either alone or in
combination with pig or other carburet of iron.
Eleventhly, I claim the employment of carbonic oxide gas in addition to
coke or other solid fuel in blast or cupola furnaces employed in recarbonizing
and melting puddled or partially puddled iron and scraps or skulls of
Bessemer iron or steel.
In witness whereof I, the said Henry Bessemer have hereunto set my
hand and seal, this Third day of May, in the year of our Lord One
thousand eight hundred and sixty-six.
HENRY BESSEMER. (L.S.)