AN IMPROVEMENT IN THE MANUFACTURE OF CAST STEEL
Year: 1859

page_text: LETTERS PATENT to Robert Mushet, of Coleford, in the County of
Gloucester, Metallurgist, for the Invention of "AN IMPROVEMENT IN THE
MANUFACTURE OF CAST STEEL."
Sealed the 27th October 1859, and dated the 3rd May 1859.
PROVISIONAL SPECIFICATION left by the said Robert Mushet at the
Office of the Commissioners of Patents, with his Petition, on the
3rd May 1859.
I, ROBERT MUSHET, of Coleford, in the County of Gloucester, Metallurgist,
do hereby declare the nature of the said Invention for "AN IMPROVEMENT IN
THE MANUFACTURE OF CAST STEEL," to be as follows:-
My Invention consists in producing a superior quality of cast steel by
melting malleable iron, together with carbonaceous matter and ores, or oxydes
of titanium, or titaniferous iron ores, or titanic acid, or deoxydized titaniferous
iron ore.
I prefer to carry my Invention into effect in the manner herein-after
explained, but I do not limit myself thereto, as the method of carrying my
Invention into effect may be varied without departing from the nature of my
said Invention.

page_text: I introduce the malleable iron, carbonaceous matter and ore, or oxide of
titanium or titaniferous iron ore, or deoxidized titaniferous iron ore into a
melting pot or crucible, such as is ordinarily used by steel melters, and which
said pot or crucible is placed in an ordinary steel melting furnace. I heat the
said substances together in the melting pot, until the titanium is reduced and
the iron is melted, and I then pour the steel thus produced into suitable moulds.
In carrying my Invention into practice I use any of the ores of titanium,
such as rutile, brookite, ilmenite, anatase, or schorlomite, or titaniferous iron
ores, such as "iserine;" or I use titanic acid separated by any convenient
process from the ores of titanium, or obtained from any, other source. I prefer
to use such ores of titanium or titaniferous iron ores as are the most free
from sulphur, phosphorous, and other impurities, such as silica.
The titaniferous iron ores may be deoxidized before use by heating them in
close chambers in contact with carbonaceous matter, or other deoxidizing
reducing agent, and when thus prepared, may be used in my process in place
of the raw ore. I prepare the ores of titanium, titaniferous iron ores, or
titanic acid, or deoxydized titaniferous iron ores for my process by stamping.
crushing, or otherwise reducing them to the state of a fine powder, and this
powder I mix with carbonaceous matter in the proportion of one part by
weight of the powdered ore of titanium, titaniferous iron ore, or titanic acid,
to from one to two parts by weight of carbonaceous matter. The carbonaceous
matter which I prefer to use is common pitch or resin; this I melt in an
iron pot or kettle, and to every twenty pounds of the pitch or resin I add,
when the pitch or resin is melted, from ten pounds to twenty pounds of the
pulverized ore of titanium, titaniferous iron ore, or titanic acid, and stir the
mixture with a rod or stick, so as to blend and thoroughly incorporate the
ingredients. I then pour out the mixture upon a cold pavement or flagstone,
which may be moistened to prevent the pitch or resin from adhering to it;
when cold, the mixture or compound may be broken up into pieces for use.
When deoxydized titaniferous iron ore is employed, one half of the above
quantities of pitch or resin will suffice; but I do not confine myself to these
proportions, though I find they answer very well, and more especially the first
proportion which I have given; other carbonaceous matter may be used in
place of pitch or resin, but I have found these substances to be very well
adapted to my purpose. The carbonaceous matter which I prefer to use in
addition to the pitch or resin mixed with the pulverized ore of titanium,
titaniferous iron ore, titanic acid, or deoxidized titaniferous iron ore, in order
to convert the malleable iron into cast steel is dry charcoal (oak charcoal is

page_text: preferable) broken into small pieces, from about the size of a pea to that of
a nut.
.
I prepare the malleable iron by cutting it up by means of shears, or in any
other convenient manner, into small pieces of a size suitable for packing
closely into the melting pots. To every forty pounds of the malleable iron I
add a quantity of the before-mentioned compound of pitch or resin, and
titanium ore, titaniferous iron ore, titanic acid, or deoxydized titaniferous iron
ore amounting to from two ounces to one pound, and a quantity of charcoal
amounting to from four ounces to twelve ounces, observing, that when I add
four ounces only of charcoal to forty pounds of malleable iron, the steel
obtained will be very soft, and such as is termed semi-steel, or homogeneous
metal. When I add eight ounces of charcoal to forty pounds of malleable
iron, the steel obtained will be possessed of a moderate degree of hardness;
and when I add twelve ounces of charcoal to forty pounds of malleable iron,
the resulting steel will be very hard; so that by varying the proportion of
charcoal the degree of hardness produced in the steel may always be regulated.
But I do not claim as of my said Invention the melting of wrought or
malleable iron with charcoal to produce cast steel. Neither do I claim as of
my said Invention the use of iron ore or oxide of iron introduced into the
melting pot along with the materials to be melted into steel.
.
The wrought or malleable iron which I prefer to make use of is good
charcoal bar iron, but other kinds of malleable iron may be advantageously
used, in order to obtain by my method a cheaper quality of cast steel, namely,
bar iron or malleable iron which has been manufactured with coke fuel,
malleable iron which has been obtained by decarbonizing pig iron, by forcing
air through it whilst in a molten state, or malleable iron obtained by de-
oxidizing ores of iron, or any mixtures of these varieties of malleable iron
which it may be found desirable to make use of.
I introduce the malleable iron, the charcoal, and the before-mentioned
compound of resin or pitch and titanium ore, titaniferous iron ores, or titanic
acid, or deoxydized titaniferous iron ore into a melting pot or crucible placed
in a suitable melting furnace, and I heat the malleable iron, the charcoal, and
the before-mentioned compound therein until the mixture is melted, I then
pour the cast steel into ingot or other moulds in the usual manner.
I do not confine myself to the proportions which I have here given, but I'
find in practice that they yield most of the different qualities of cast steel-
required in commerce, and produce excellent results.
The pots or crucibles which I prefer to use, and the furnaces in which they.
}

page_text: are placed and heated, are such as are generally used by manufacturers of
cast steel. "Iserine," which is a titaniferous iron ore, contains about ten per
centum of titanic acid, and about eighty-six per centum of oxides of iron, and
I find it an excellent ore to use for my process.
The essence of my Invention consists in heating and melting malleable or
wrought iron with ore of titanium, titaniferous iron ore, titanic acid, or
deoxydized titaniferous iron ore, and carbonaceous matter, in order to produce
by the fusion together of these substances an improved quality of cast steel.
In carrying my Invention into practice, oxyde of manganese, or oxyde of
manganese with carbonaceous matter may likewise be added to the steel in
the melting pot; but such an addition forms no part of my said Invention.
Scrap steel may likewise be added, but such addition forms no part of my
claim, neither is it essential to the success of my process.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Mushet in the Great Seal Patent Office on the
1st November 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
MUSHET, of Coleford, in the County of Gloucester, Metallurgist, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of May, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Robert Mushet, Her special licence that I, the said
Robert Mushet, my executors, administrators, and assigns, or such others
as I, the said Robert Mushet, 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 "AN IM-
PROVEMENT IN THE MANUFACTURE OF CAST STEEL," upon the condition (amongst
others) that I, the said Robert Mushet, 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

page_text: in the Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Mushet, 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 fol-
lowing statement thereof, that is to say :-
My Invention consists in producing a superior quality of cast steel by
melting malleable iron together with carbonaceous matter and ores or oxides
of titanium, or titaniferous iron ores, or titanic acid, or deoxydized titaniferous
iron ores.
I prefer to carry my Invention into effect in the manner herein-after
explained, but I do not limit myself thereto, as the method of carrying my
Invention into effect may be varied without departing from the nature of my
Invention.
I introduce the malleable iron, carbonaceous matter, and ore or oxide of
titanium or titaniferous iron ore, or deoxidized titaniferous iron ore into a
melting pot or crucible, such as is ordinarily used by steel melters, and which
said pot or crucible is placed in an ordinary steel melting furnace. I heat the
said substances together in the melting pot until the titanium is reduced, and
the iron is melted and alloyed with the titanium, and I then pour the steel
thus produced into suitable moulds.
In carrying my Invention into practice I use any of the ores of titanium,
such as rutile, brookite, ilmenite, anatase, or schorlomite, or titaniferous iron
ores, such as iserine or other titaniferous iron ores, which, though they exist in
abundance, have not been classified by mineralogists; or I use titanic acid,
separated by any convenient process from the ores of titanium, or obtained
from any other source. I prefer to use such ores of titanium or titaniferous
iron ores as are for the most part free from sulphur, phosphorous, and other
impurities, such as silica.
The titaniferous iron ores may be deoxidized before use by heating them in
close chambers in contact with carbonaceous matter or other deoxydizing or
reducing agent, and when thus prepared the said ores may be further prepared
for use in my process by stamping, crushing, or otherwise reducing the said
titaniferous iron ores to the state of a fine powder, and this powder I mix with
carbonaceous matter in the proportion of one part by weight of the powdered
ore of titanium, titaniferous iron ore, or titanic acid to from one to two parts
by weight of carbonaceous matter. The carbonaceous matter which I prefer
to use is common pitch or resin. This I melt in an iron pot or kettle, and to

page_text: every twenty pounds of the said pitch or resin I add, when the pitch or resin
is melted, from ten pounds to twenty pounds of the pulverized ore of titanium,
titaniferous iron ore, or titanic acid, and I stir the mixture with a rod or stick
so as to blend and thoroughly incorporate the ingredients; I then pour out
the mixture upon a cold pavement or flagstone, which may be moistened to
prevent the pitch or resin from adhering to it. When cold the mixture or
compound may be broken up into pieces for use. When deoxydized titaniferous
iron ore is employed, one half or less than one half of the last described pro-
portion of pitch or resin will suffice in mixture with the said deoxydized
titaniferous iron ore; but I do not limit myself to these proportions, though I
find they answer very well. Other carbonaceous matter may be used in place
of pitch or resin, but I have found these substances to be very well adapted to
my purpose. In addition to pitch or resin, or other carbonaceous matter
mixed with the pulverized ore of titanium, titaniferous iron ore, titanic acid, or
deoxidized titaniferous iron ore, 1 sometimes prefer to employ a further pro-
portion of carbonaceous matter, in order to convert the malleable iron during
fusion into cast steel, and for this purpose I use dry charcoal (oak charcoal is
preferable) broken into small pieces from about the size of a pea to that of
a nut.
A
I prepare the malleable iron by cutting it up by means of shears, or in any
other convenient manner, into small pieces of a size suitable for packing
closely into the melting pots. To every forty pounds of the malleable iron
thus prepared I add a quantity of the before-mentioned compound of pitch or
resin and titanium ore, amounting to from two ounces to one pound, and a
quantity of charcoal amounting to from four ounces to twelve ounces, observing
that when I add four ounces only of charcoal to forty pounds of malleable iron
the steel obtained will be very soft, and such as is termed semi-steel or homo-
geneous metal. When I add eight ounces of charcoal to forty pounds of
malleable iron the steel obtained will be possessed of a moderate degree of hard-
ness; and when I add twelve ounces of charcoal to forty pounds of malleable
iron the resulting steel will be very hard, so that by varying the proportion
of charcoal the degree of hardness produced in the steel may always be
regulated.
But I do not claim as of my said Invention the melting of wrought or
malleable iron with charcoal to produce cast steel apart from the use of titanic
compounds; neither do I claim as of my said Invention the use of iron ore or
oxide of iron introduced into the melting pot along with the materials to be
melted into steel. I sometimes melt bar or malleable iron with the compound

page_text: of pitch or resin, and titanic acid or ore of titanium, and without any addi-
tional quantity of carbonaceous matter, in order to produce a strong and
tenacious kind of semi-steel, and in this case I proceed as follows:-To forty
pounds of good charcoal or other bar iron cut into pieces of a size suitable for
packing into the melting pots I add one pound of the compound of pitch and
ore of titanium, which I have herein-before described.. I introduce the said bar
iron and the said compound into a melting pot or crucible placed in an ordi-
nary steel melting furnace, and I beat the iron and the said compound therein
until the titanium is reduced, and the iron is melted and alloyed with it. I
then withdraw the melting pot from the furnace, and pour the metal or semi-
steel produced into an ingot or other suitable mould prepared for the purpose.
The wrought or malleable iron which I prefer to make use of in practising
my Invention is good charcoal bar iron, such, for instance, as Swedish or
Russian charcoal bar iron, but other kinds of malleable iron may be advan-
tageously used in order to obtain by my method a cheaper quality of cast steel,
namely, bar iron or malleable iron of superior quality, which has been manu-
factured with coke fuel, malleable iron which has been obtained by decar-
bonizing pig iron by forcing air through it whilst in a molten state, or
malleable iron obtained by deoxidizing ores of iron, or any mixtures of these
varieties of malleable iron which it may be found desirable to make use of,
and in each case I introduce the malleable iron, the charcoal, and the before-
mentioned compound of resin or pitch, and titanium ore, titaniferous iron ore,
or titanic acid, or deoxydized titaniferous iron ore into a melting pot or
crucible placed in a suitable melting furnace, and I heat the malleable iron,
the charcoal, and the before-mentioned compound therein until the mixture is
melted. I then pour the cast steel thus obtained into ingot or other moulds
in the usual manner.
The pots or crucibles which I prefer to use, and the furnaces in which they
are placed and heated, are such as are generally used by manufacturers of
cast steel.
Iserine," which is a titaniferous iron ore containing about ten
per centum of titanic acid, and about eighty-six per centum of oxides of iron
I find to be an excellent ore to use for my process. Ilmenite, likewise, which
is a mineral composed of titanic acid and oxides of iron in about equal pro-
portions, produces excellent results when used for my process.
The essence of my Invention consists in melting malleable or wrought iron
with ore of titanium, titaniferous iron ore, titanic acid, or deoxidized tita-
niferous iron ore and carbonaceous matter, in order to produce by the fusion
together of these substances an improved quality of cast steel.

page_text: In carrying my Invention into practice oxide of manganese, or oxide of
manganese with carbonaceous matter, may likewise be added to the steel in
the melting pot, but such an addition forms no part of my said Invention.
Scrap steel may likewise be added, but such addition forms no part of my
Invention, neither is essential to the success of my process.
In witness whereof, I, the said Robert Mushet, have hereunto set my
hand and seal, this Twenty-fourth day of October, in the year of our
Lord One thousand eight hundred and fifty-nine.
Witnesses,
EDWP.. M. MUSHET,
Coleford, Gloucestershire.
BROOKLYN MUSHET,
Coleford, Gloucestershire.
ROBT MUSHET. (L.S.)