IMPROVEMENTS IN THE MANUFACTURE OF STEEL AND IRON, AND. IN THE PREPARATION OF MATERIALS AND AGENTS AND IN APPARATUS TO BE EMPLOYED THEREIN
Year: 1868

page_text: LETTERS PATENT to James Hargreaves, of Darlington, in the
County of Durham, Analytical Chemist, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF STEEL AND IRON, AND. IN THE
PREPARATION OF MATERIALS AND AGENTS AND IN APPARATUS TO BE EMPLOYED
THEREIN."
Sealed the 5th February 1869, and dated the 6th August 1868.
i
PROVISIONAL SPECIFICATION left by the said James Hargreaves at
the Office of the Commissioners of Patents, with his Petition, on
the 6th August 1868.
I, JAMES HARGREAVES, of Darlington, in the County of Durham,
. Analytical Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF STEEL AND IRON AND IN THE
PREPARATION OF MATERIALS AND AGENTS AND IN APPARATUS TO BE EMPLOYED.
THEREIN," to be as follows:-
First. During the manufacture of steel or malleable iron from cast
iron by any of the processes in which the carbon and other impurities
are removed by the action of currents of oxygen ascending through

page_text: fused cast iron, such for instance as the Bessemer process, or where
the conversion is effected by passing oxygen gas evolved from salts
containing and capable of yielding oxygen, such as nitrates, chlorates,
chromates, and manganates, I project into the converting vessel or
other apparatus in which the cast iron is being operated upon a
current of oxygen gas or atmospheric air or other gas containing
oxygen. I inject the said oxygen or other gas containing oxygen above
the surface of the metal and slag or at a slight depth below the surface,
I prefer however to direct it downwards upon the surface of the metal
and slag; and I further prefer that the oxygen or other gas should be
heated.
Second. In the Bessemer process I heat the air used in converting
cast iron into steel previous to passing the said air below and through
the iron in the converting vessel by conveying it through a coil of pipes
heated by the hot gases evolved from the said converting vessel.
Third. (A.) when making steel or soft iron by the use of such salts
as yield oxygen, and which salts are hereafter called oxydising salts,
I employ a converting vessel of any desired shape formed with an
outlet opening in its bottom.. I close the said outlet opening by a
plate or piece of fusible metal or other suitable fusible substance, and
tamp or pack the oxydising salts thereon into a solid mass or other-
wise in any suitable manner. The molten iron is poured upon the said
oxydising salts, and when the reaction is completed the fusible metal
or substance becomes fused and allows the steel or malleable iron to
run at once into the ingot mould or elsewhere. Or (B.) I place over
the said outlet opening a thin plate of iron or other material, which
when exposed to the heat of the molten steel or iron in consequence
of the removal of the oxydising salts at first placed over it will become
melted or softened, and allow the said molten steel or iron to run out
of the converter as aforesaid. Or (C.) I provide a plug which extends
from the bottom of the said converting vessel to above the top thereof;
the said plug fits into or over the said outlet opening and serves as a
stop during the reaction of the oxydising salts. On the completion of
the reaction the steel or iron is allowed to flow out at pleasure by with-
drawing the said stop plug.
Fourth. When making steel or soft iron by the use of oxydising salts,
I employ a converting vessel which serves also as a mould. The said
converting vessel serving the double purpose as aforesaid I for brevity

page_text: hereafter call the mould converter. The said mould converter is made
of any desired form, and is lined with ganister, loam, fire-clay, or other
suitable refractory substance, or is made of fire-clay, fire-stone, or other
like substance. It is made sufficiently deep to prevent the molten iron
during conversion from being projected over the top thereof by the
action of the liberated gases, or instead of making it deep I place on
the top thereof in an inverted position another mould of the same kind.
The steel or iron is allowed to solidify in the said mould converter, at the
bottom of which as will be obvious the oxydising salts are place before
the molten cast iron is run in. When required the sides of the said
mould converter are made in two or more pieces so that they can be
separated to allow of easy removal of the ingot or other piece.
Fifth. When making steel or soft iron from cast iron by the
Bessemer or any other process in which oxygen is caused or allowed
to rise through the molten cast iron, I provide a dam or vessel to retain
or hold the cast iron as run from a blast furnace or cupola, so that
such iron can there be maintained at a high temperature until required
for the converting vessel or apparatus.
The said dam or vessel is by
"
preference made of the same form as the cavity in the bed of a
reverberatory furnace used for fusing iron, and is covered in a similar
manner. It can be made sufficiently large to contain a whole "cast"
from a blast furnace, and the said "cast can be kept at a high
temperature by flame from a fire or in the manner which is usual with
a Siemans' regenerative gas furnace.
When Siemans' regenerator is
used I prefer to employ the waste blast furnace gases as the fuel: The
molten iron is tapped from the said dam or vessel into crane or other
suitable ladles in suitable quantities for being poured into the converters,
or is run direct into the said converters.
Sixth. I make steel or soft iron from cast iron by the following
process: I run molten cast iron into the bed of a furnace in connection
with a Siemans' regenerator. I prefer that the cast iron should be run
direct from a blast furnace or cupola, and use the waste gases from a
blast furnace or cupola as fuel. I react upon the said molten cast iron
whilst it is in the bed of the furnace by means of metallic oxides, such
as oxides of iron and manganese and oxydising salts as aforesaid, or I
cause currents of oxygen or other gas containing.oxygen to react upon
the cast iron so as to remove the carbon and other impurities.
Seventh. (A) as means for withdrawing molten steel or iron from

page_text: a. reverberatory or other like furnace, I employ a tube or conduit of
fire-clay, plumbago, or other refractory substance. The said tube or
conduit is led from the bottom of the furnace bed to the outside of the
furnace, and is stopped with sand, ground coke, ground charcoal,
plumbago, or other suitable refractory substance which can be tapped
when required.
To regulate the outward flow of the steel or iron I
employ in some cases a plug or rod passed against the inner end of
the tube or conduit from outside the furnace. (B) or I close the
inner end of the said tube or conduit by a plug or valve of a refractory
substance, which by being connected to a protected rod can be opened
more or less at pleasure so as to regulate the outflow of the steel or
iron.
Eighth. When making steel or malleable iron by any of the processes
in which oxygen or gas containing oxygen is caused or allowed to pass
through molten iron, I add to the said molten iron oxide of iron, oxide
of manganese, or lime in any desired quantity; and I prefer that the
said oxides or lime should be in a highly heated condition.
Ninth. When making steel or malleable iron by the Bessemer process
or other process substantially the same, I add oxydising salts prepared
as hereafter described under this head to the converter at the time air
is being forced through the fused iron. The said salts are prepared by
being made into a solid mass or masses either by moistening and
drying, or by fusing and cooling; and I prefer to mix with the said
oxydising salts before moistening the drying or fusing and cooling oxide
of iron, oxide of manganese, or anhydrous lime to prevent the too rapid
decomposition of the solid mass or masses, and also to furnish basic sub-
stances with, which the silica acid, sulphur, and phosphorous or phos-
phoric acid may combine. The oxydising salts which I prefer to use
are the nitrate, nitrite, chromate, or manganate of soda, or the corre-
sponding salts of potassa, or any one of them.
Tenth. When making steel or malleable iron by the use of an
oxydising salt, or by oxydising salts, I proceed as follows:-I first
thoroughly dry the said salt or salts and reduce it or them to powder;
I then place the said dried powder at the bottom of the vessel to be
used as a converter, by preference having first mixed it with some inert
substance to regulate its action. The substances I prefer to use are
oxide of iron and oxide of manganese, as set forth in the Specification
of an Invention for which Letters Patent were granted to me and

page_text: Thomas Robinson on the 22nd May 1867, No. 1520. In some cases I
do not mix the whole bulk of the required oxydising salt or salts with
the metallic oxides or other inert substance, but place a layer of the
said oxides or other substance over the salt or salts to prevent too rapid
action when the molten metal is poured on the said salt or salts.
Note. I would have it understood that whenever the term "steel"
is used, refined iron or other iron of composition intermediate between
that of cast iron and malleable or soft iron is also intended, meant, and
implied, as in all cases I do not carry the reaction so far as to produce
iron in the condition commonly called steel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Hargreaves in the Great Seal Patent Office
on the 6th February 1869.
h
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
HARGREAVES, of Darlington, in the County of Durham, Analytical
Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of August, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of. Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said James Hargreaves, Her special license that
I, the said James Hargreaves, my executors, administrators, and assigns,
or such others as I, the said James Hargreaves, my executors, adminis-
trators, 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 STEEL AND IRON, AND IN THE PREPARATION OF MATERIALS AND AGENTS AND
IN APPARATUS TO BE EMPLOYED THEREIN," upon the condition (amongst others)
that I, the said James Hargreaves, 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

page_text: calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said James Hargreaves, do hereby declaro
the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and
to the
by the following statement thereof, reference being had
accompanying Sheets of Drawings, and to the figures and letters thereon,
that is to say:-
I have ascertained that phosphorous and sulphur are more readily
separated from iron where the cinder formed during the reaction contains
metallic oxides, such as those of iron, manganese, sodium, and potassium,
and the said oxides are free from combination with silicic or other acids,
and further that when the oxide of iron is in the state of proto-sesqui-
oxide or magnetic oxide the phosphorous and sulphur are more readily
removed from the metal which is being operated upon and transferred
to the slag or cinder. In the Bessemer operation for making steel as
at present conducted a very small excess of oxide of iron is formed
over and above that necessary to combine with the silicic acid (formed
by the oxidation of the silicon origininally present in the pig iron) to
form a mono-silicate of protoxide of iron. All the oxide of iron thus
combined with silicic acid is inert so far as the extraction of phosphorous
is concerned. Any oxide of iron that may be formed at the tuyeres in
the Bessemer converter is very rapidly reduced to the metallic state
while ascending though the fused carbonaceous iron, and to maintain
an excess of basic matter to combine with phosphorus or phosphoric
acid I proceed as set forth in the first and ninth parts of my said
Invention.
First. During the manufacture of steel or malleable iron by any of
the processes in which the carbon, silicon, and other impurities are
removed by the action of currents of oxygen ascending through fused
cast iron, such for instance as the Bessemer process, or where the
conversion is effected by passing oxygen or compounds thereof evolved
from salts capable of yielding oxygen by the action of heat and carbon-
aceous matter, such for example as the nitrates, chlorates, chromates,
and manganates, I project into the converting vessel or other apparatus
in which the cast iron is being operated upon by ascending currents of
oxygen or compounds thereof as aforesaid a current of oxygen gas or
atmospheric air or other compounds capable of evolving oxygen, whether

page_text: the said compound of oxygen be in a gaseous, liquid, or solid condition.
Instead of oxygen gas or atmospheric air the aforesaid compound of
oxygen may consist of nitrate of soda or nitrate of potassa, or chlorate
of soda or chlorate of potassa, or other salt which yields oxygen injected
upon the surface of the iron which is being operated upon as aforesaid
by ascending currents of oxygen. I inject the said oxygen gas or
atmospheric air or oxygen yielding salt or other compound capable of
evolving oxygen above the surface of the iron and slag being operated
upon by the ascending currents of oxygen or compounds thereof as
aforesaid or at a slight depth below the surface. I prefer however to
direct the current of oxygen or compound thereof as aforesaid downwards
upon the surface of the metal and slag; and I further prefer that the
oxygen gas or atmospheric air or oxygen yielding salt or compound
capable of evolving oxygen should be heated previous to being injected
The
upon or near the surface of the metal and slag as aforesaid.
temperature of the converter is elevated by the combustion of the
evolved carbonic oxide within the converter.
The apparatus by which I prefer to effect the first part of my Invention
in connection with the Bessemer process is set forth in Fig. 1, Sheet A.
a is the tube conveying air under pressure from the air reservoir, and
which tube for brevity and the purpose of this Specification I call the
oxydising tube; it is protected from the intense heat of the evolved
gases by a covering tube of plumbago 6 or other refractory substance.
The said tube a is serrated or roughened on the outside, and the covering
tube of plumbago b is also serrated or roughened on the inside, and
the small space which remains between a and b is rammed hard with
moist fire-clay, and then gradually dried and heated to dull redness
to expel the last trace of water, when the tube is ready for use. The
said tube a with the plumbago covering tube b is attached to the pipe c
provided with swivel joints d, and these parts are supported by a chain e
and pulley f, so that the whole can be taken out of the way at or near
the conclusion of the decarburizing operation. g is a pipe for conveying
air from the reservoir under pressure; h, valve for regulating the flow of
air. If necessary I place a coil of pipe close to c, whereby by the evolved
hot waste gases from the converter the air may be heated before being
injected upon or near the surface of the metal in the converter.
•
The method by which I prefer to effect the first part of my said
Invention in connection with those processes in which the decarburization

page_text: or purification of the iron is effected by the action of oxygen evolved
from oxydising salts, such as nitrates, chlorates, chromates, and manga-
nates, is set forth in Fig. 2. a¹, converting vessel; 6', layer of oxidising
salt; c', molten iron; d', opening in the side of the converter through
which are passed two pipes e¹. The said opening d¹ is stopped up with
clay or loam to prevent the metal from running out during ebulition
caused by the action of the oxidising salt. Air is forced through the
pipes e' at a high pressure during the said ebulition.
Second. When cast iron containing a small proportion of carbon is
used in the Bessemer process the temperature of the metal at the end
of the operation is too low to admit of casting good solid ingots. To
assist in the elevation of the temperature of the metal I heat the air
used in decarburising cast iron and converting it into steel previous to
passing the said air below or through the iron in the converting vessel
by conveying the said air through a coil of pipes heated by the hot
gases evolved from the said converting vessel, or I heat the said air by
other means, substantially the same.
The apparatus by which I prefer to carry the second part of my
Invention into effect is also illustrated by Fig. 1. i denotes the trunnion
through which air is admitted from the blowing engine. A pipe j is
led therefrom to a coil k placed in an outlet aperture 1; the said
aperture is lined with loam or other refractory substance. The coil of
pipe is continued by a descending pipe m to the air chest n, and the
air admitted passes through the twyeres o into the converter through
amongst the molten metal. The air in its passage through the coil k is
highly heated by the escaping hot waste gases.
Third. (A.) when making steel or soft iron by the use of such salts
as yeild oxygen, such for example as nitrates, chlorates, chromates, and
manganates, and which said salts I for the purpose of this Specifica-
tion call oxidising salts, I employ a converting vessel of any desired or
convenient shape; the said vessel is formed with an outlet in its bottom.
I close the said outlet or opening by a plate or piece of fusible metal or
other suitable fusible substance, and tamp or pack the said oxidising
salt or salts thereon into a solid mass, or otherwise in any suitable manner.
The molten iron is poured upon the said oxidising salts, and when the
reaction is completed the fusible metal or other suitable fusible substance
becomes fused in consequence of the removal of the covering of oxidising

page_text: salt and allows the malleable iron or steel to run at once into an
ingot mould or other suitable receptacle. But that this part of
my said Invention may be better understood I have illustrated by
Fig. 3, which is a vertical section, the lower part of a converting
vessel. a³, the converting vessel; be, fusible plug, which may consist
of fused and solidified carbonate of soda or other substance which is
not injurious to the steel; c, the oxidising salt; d, molten iron.
Or (B.) I place over the said outlet opening a thin plate of iron or other
material which when exposed to the heat of molten steel or iron in
consequence of the removal of the oxidising salts at first placed over
the said plate the said plate will become melted or softened and allow
the said steel or iron to run out of the converter in the same manner as
when a fusible plug is used. This part of my said Invention is shewn
on the Drawings by Fig. 4, also a vertical section. es, thin plate of
iron; f, the oxidising salt; g2, the melted iron. Or (C.) I provide a plug
suitably protected by a coating of fire-clay, loam, or other refractory
substance; which said plug extends from the bottom of the converting
vessel to the top thereof. The lower end of the said plug fits into or over
the outlet or opening in the bottom of the said converter, and the said
plug is put into its place before the oxidising salts are packed in a solid
state.or otherwise at the bottom of the said converting vessel, and serves
to stop any outlet of fused metal at the bottom of the said converting
vessel during and after the reaction of the said oxidising salts. After
the completion of the aforesaid reaction and the slag has had time to
,separate from the fused steel or soft iron the aforesaid iron or steel is
allowed to flow out at pleasure by withdrawing the said plug. But
that this part of my said Invention may be better understood a vertical
section of a converting vessel with a suitable refractory lining is
delineated by Fig. 5 on the Drawings. h³, the stop plug; 2, oxidising
salt; j, fused iron; ³, lever for raising the plug h; 1, outlet; m³,
opening at the top of the converter to pour in the metal and allow the
evolved gases to escape; n³, cramps by which the cover of the con-
verting vessel is held in its place; o³, supports of the converter.
Fourth. When making steel or soft iron by the use of oxydising salts
such as aforesaid 'I employ a converting vessel which serves as a mould,
and which for brevity and the purpose of this Specification I call a
mould converter. The said mould converter is made of any desired form,
and is lined with ganister, loam, fire-clay, or other suitable refractory

page_text: substance, or is made of fire-brick, fire-stone, or other like refractory sub-
stance. The said mould converter is made sufficiently deep to prevent
the molten iron and steel from being projected over the top thereof by the
action of the liberated gases; or instead of making the mould converted
of great depth I place on the top of the said mould converter another
vessel of the same kind, so as to furnish the required additional space;
or I place over the top of the said mould converter a vessel open at the
bottom and closed at the top, with the exception of a hole or passage to
allow the exit of the evolved gases. The said oxidising salt or any of
them are placed at the bottom of the said mould converter, and the fused
iron is then poured upon the said oxidising salt or oxidising salts.
The
evolved oxygen from the said oxidising salt or oxidising salts effects the
conversion of the said cast iron into steel or malleable iron, and when,
the aforesaid conversion of the said cast iron into steel or soft iron is
effected as aforesaid the said steel or soft iron runs into the lower part
of the said mould converter, where the said steel or soft iron solidifies
into an ingot or casting. When required the sides of the said mould
converter are so made that they can be separated to allow the said ingot
or casting to be easily removed.
One of the forms of apparatus which I employ under this part of
my Invention is fully illustrated by Figs. 6, 7, 8, and 9 on Sheet A
of the Drawings. Fig. 6 is a vertical section; Figs. 7 and 8, views in
side elevation; and Fig. 9 a top or plan view. In all these views like
letters denote the same parts.
The mould converter proper is here shewn made of two side pieces 6³,
and a bottom piece c³; d, hood or expanded part with hood cover e³;
f3, mouth of hood. All these parts are delineated so that bolts and nuts
or cramps can be employed for connecting them together. It will be
obvious however any convenient mechanical couplers or fasteners can
be used, the object being to allow of easy separation and fitting together.
g3, lugs for lifting off the hood; h³, oxidising salt or salts; ³, fused metal.
The oxidising salt or salts as will be obvious is or are placed at the
bottom of the aforesaid mould converter, the hood is then fixed or fastened
on the top thereof by the cramps or other fasteners, and the metal
poured through the mouth f³. When the action of the oxidising salt
commences, and it will do so at once, a part of the metal during
ebulition is forced into the hood d³, and the evolved gases make their
escape at the mouth f³. When the reaction is completed the fused

page_text: steel or soft iron settles in the lower part, from which when solidified it
is extracted by taking the converter to pieces. I prepare the ingot
mould for use by coating the internal surface of it with loam or other
refractory substance, and I employ for this purpose a block of wood or
other material of less diameter than the inside of the converter. Between
the said block and the iron shell I ram in the said loam or other material
then withdraw the block and put the mould converter in a stove to dry,
when dry it is ready for use. The hood and hood cover aforesaid after
being used on, the top of one mould converter proper are removed in
one piece. to another, and affixed thereto and again used while hot.
The joint between the hood and the mould converter is made good by a
layer of loam between the flanges of the said hood and mould converter
proper. I would have it distinctly understood that I do not confine
myself to any particular form of mould converter or means of connect-
ing the parts thereof so long as the vessel serves the double purpose of
a converter and ingot mould.
Fifth. When making steel or soft iron by the Bessemer or any
other process in which oxygen is allowed to rise through the
molten cast iron I provide a dam or vessel to retain or hold the
cast iron as run from a blast furnace or cupola, so that such iron can
there be maintained at a high temperature until required for the con-
verting vessel or apparatus, and also allow the metal to be sampled or
The said dam or vessel is by
submitted to preliminary treatment.
preference made of the same form as the cavity in the bed of a
reverberatory furnace used for fusing iron and is covered in a similar
manner; it may be made sufficiently large to contain a whole "cast"
from a blast furnace, and the said "cast" can be kept at a high
temperature by flame from a fire as in the ordinary manner, or in the
When
manner which is usual in the Siemens' regenerative furnace.
Siemens' regenerative furnace is used I prefer to employ the waste blast
furnace or cupola gases as the fuel, and as the blast furnace gas or
cupola gas is already heated I prefer to use regenerators for the air
only, but use regenerators for both the air and gas if the gas is of so low
a temperature as to require it. The molten iron is tapped from the said
dam or vessel into crane or other suitable ladles in suitable quantities for
being poured into the said converter.
"That this part of my said invention may be clearly understood in
detail, I have attached. two Sheets of Drawings marked B and C.

page_text: Fig. 9 is a longitudinal vertical section at the line A, B; Fig. 10, a
transverse section at the line C, D; Fig. 11, a front longitudinal elevation
of the base of the regenerators; and Fig. 12 a plan. Like letters denote
the same parts in all these views.
a, cupola or blast furnace; b, runner to convey fused iron from the
cupola to the dam of the gas furnace; c', bed of gas furnace; d', passage
to convey carbonic oxide from the cupola to the gas furnace; e', slits
to convey gases from the cupola to the furnace; f', point of com-
bustion of gas and hot air from regenerator; g*, passage from regenerator
to furnace; h, regenerator; i, ³, and j, j, two openings. These
openings are divided into two parts by plates ', which form the tops
of the flues. The upper parts of the said openings communicate with
the atmosphere, and the lower parts with the chimney flue. m, dampers
which balance each other over pulleys n', n³. One of the dampers is
shewn lowered, and the other raised. Air enters the regenerator at
the side where the damper is lowered, and the waste gases from the gas
furnace enter the flue on the side on which the damper is raised. By
raising and lowering the damper alternately at intervals the direction.
of the air current is reversed. o, o, balance dampers to regulate the
The carbonic oxide or cupola gas is
passage of gas from the cupola.
admitted to the furnace at the side on which either of the dampers o, o³,
is raised, and such carbonic oxide is admitted as aforesaid at f, where
combustion takes place. The metal is tapped from the blast furnace,
and passes along the runner b* into the bed of the gas furnace c', where
it is kept at a high temperature and sampled or subjected to any
preliminary treatment previous to being run into the converter, where
the carbon, silicon, and other impurities are removed by the action of
currents of oxygen as aforesaid.
Sixth. I make steel or soft iron from cast iron by the following
process: I run molten cast iron into the bed of a furnace in connection
with a Siemens' regenerator. I prefer that the cast iron should be run
direct from a blast furnace or cupola, and I use the waste gases from a
blast furnace or cupola as fuel. I react upon the said molten cast iron
whilst it is in the bed of the furnace by means of metallic oxides, such
as oxides of iron and manganese, and oxidising salts as aforesaid, or I 3
cause currents of oxygen or other gas containing oxygen to react upon
the cast iron so as to remove the carbon and other impurities.

page_text: In carrying this part of my Invention into operation I proceed in the
manner and with the furnace and apparatus described in the above fifth
part, but instead of running the molten cast iron from the bed of the
gas furnace into a separate converter I react upon the said cast iron
by means of metallic oxides, such as oxide of iron and manganese,
oxidising salts, or currents of oxygen or other gas containing oxygen, or
either of them, to remove the carbon, silicon, and other impurities.
whilst the molten metal remains in the bed of the furnace.
Seventh. (A.) as means for withdrawing molten steel or iron from a
reverberatory or other like furnace, I employ a tube or conduit of
fire-clay, plumbago, or other suitable refractory substance. The said
tube or conduit extends from the bottom of the furnace bed to the
outside of the furnace, and the said tube or conduit is stopped with
sand, ground coke, ground charcoal, or other suitable refractory sub-
stance. When the furnace is required to be tapped the said sand, ground
coke, ground charcoal, or other refractory substance is forced or pushed
out. (B) to regulate the outward flow of the steel or iron I employ in
some cases a plug or rod passed against the inner end of the tube or
conduit from outside the furnace; or I close the inner end of the said
tube or conduit by a plug or valve of a refractory substance, which by
being connected to a protected rod can be opened more or less at
pleasure, so as to regulate the outflow of the steel or iron.
This part
of my said Invention will be better understood by referring to Figs. 9
and 10. p, the outlet or conduit; q', the plug to regulate the flow
of the melted iron or steel; r³, guides which hold the stopper in its
place; stopper. The aforesaid conduit p' may be stopped with any
suitable refractory substance as aforesaid, and when it is required to let
out the fused metal the stopper t is withdrawn, when the aforesaid
refractory substance drops out or is easily removed, and the metal flows
through the said outlet or conduit. The flow of the fused iron or steel
may be regulated by the plug q', which can be controlled by a person at
the top of the furnace; or a plug can be inserted at the furnace door u
to regulate the outflow.
Eighth. When making steel or malleable iron by any of the processes
in which gas containing oxygen evolved from oxidising salts is used
and caused or allowed to rise through the molten metal, I add to the
said molten metal oxide of iron, oxide of manganese, or lime in any

page_text: desired quantity, and I prefer that the said oxides of iron or manganese
should be in a highly heated or fused condition.
In carrying this part of my Invention into effect I take a converting
vessel of any suitable shape and tamp or pack the required oxidising
salts into the bottom thereof. I then pour in the molten cast iron, and
at the same time or immediately thereafter add the oxide of iron, oxide
of manganese, or lime.
When operating on ordinary mottled pig iron
to produce tough iron of a speedy nature, by this part of my Invention I
use for every hundredweight of melted iron about two pounds of nitrate
of soda and about sixty pounds of fused oxide of iron. When the iron
to be operated upon contains a large proportion of sulphur I prefer to
employ oxide of manganese and lime with the said oxide of iron, but it
will be obvious the proportions of the materials must be varied to suit
the character of the metal being heated and the quality of the product
desired.
I would have it distinctly understood that this part of my Invention
does not extend to the use of the said oxides of iron and manganese and
lime when currents of atmospheric air are forced through or into molten
cast iron.
Ninth. When making steel or malleable iron, by the Bessemer process
or other process substantially the same I add oxidising salts prepared
as hereafter described under this head to the converter at the time air is
being forced through the fused iron. The said salts are prepared by
being made into a solid mass or masses either by moistening the said
salts or any of them and then drying, or by fusing the said salts or any
of them and then cooling; and I prefer to mix with the said oxidising
salts before moistening and drying or fusing and cooling oxide of iron,
oxide of manganese, or anhydrous lime to prevent the too rapid decom-
position of the solid mass or masses, and also to furnish basic substances
with which the silicic acid, sulphur, and phosphorous or phosphoric acid
may combine, and in other respects react on the iron by reason of the
evolution of oxygen, as set forth in the first part of my said Invention.
The oxidising salts which I prefer to use are the nitrate, nitrite, chromate,
or manganate of soda, or the corresponding salts of potassa, or any
of them.
Tenth. When making steel or malleable iron by the use of an
oxidising salt or by oxidising salts I proceed as follows:-I first
thoroughly dry the said salt or salts, and reduce it or them to fine

page_text: powder. I then place the said dried powder at the bottom of the vessel
to be used as a converter, by preference having first mixed it with some
inert substance to regulate its action. The substances I prefer to use
are oxide of iron and oxide of manganese, as set forth in the Specifica-
tion of an Invention for which Letters Patent were granted to me and
Thomas Robinson on the 22nd May 1867, No. 1520. In some cases I
do not mix the whole bulk of the required oxidising salt or salts with
the metallic oxides or other inert substance, but place a layer of the said
oxides or other substance or mixture of oxidising salts with other sub-
stance over the salt or salts to prevent too rapid action when the molten
metal is poured on the said oxidising salt or salts.
Note. I would have it understood that wherever the term "steel" is
used, refined iron or other iron of composition intermediate between that
of cast iron and malleable or soft iron is also intended, meant, and
implied, as I do not in all cases carry the reaction of oxidising agents so
far as to produce iron in the condition commonly called steel.
And now having described the nature of my said Invention, and
particularly set forth to the best of my ability how the same is carried
into effect in practice, I claim the several improvements herein described
for the purposes set forth.
In witness whereof, I, the said James Hargreaves, have hereunto
set my hand and seal, this Fourth day of February, in the
year of our Lord One thousand eight hundred and sixty-nine.
5 Witness,
JOHN T. KING.
JAMES HARGREAVES. (L.S.)