INVENTION OR IMPROVEMENT FOR THE MAKING OR MANUFACTURING BAR OR OTHER IRON FROM CERTAIN REFUSE SLAGS OR CINDERS PRODUCED IN THE SMELTING OF COPPER ORES AND IN THE MANUFACTURING OF COPPER
Year: 1818

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
MUSIET, of Coleford, in the County of Gloucester, Iron Master, send
greeting.
WHEREAS His present Majesty King George the Third, by His Royal
Letters Patent under the Great Seal of Great Britain, bearing date the
Eighteenth day of April now last past, did give and grant unto William Crawshay
the younger, of Cyfarthfa Iron Works, in the County of Glamorgan, Esquire,
and me, the said David Mushet, His especial licence that we, the said William
Crawshay and David Mushet, our executors, administrators, and assigns, or
such others as we, the said William Crawshay and David Mushet, our
executors, administrators, or assigns, should at any time agree with, and no
others, during the term of years therein expressed, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of
Berwick-upon-Tweed, our "INVENTION OR IMPROVEMENT FOR THE MAKING OR
MANUFACTURING BAR OR OTHER IRON FROM CERTAIN REFUSE SLAGS OR CINDERS
PRODUCED IN THE SMELTING OF COPPER ORES AND IN THE MANUFACTURING OF
COPPER;" in which said Letters Patent there is contained a proviso obliging
us, the said William Crawshay and David Mushet, by an instrument in
writing under our hands and seals, or under the hand and seal of one of us,
particularly to describe and ascertain the nature of our said Invention, and in
what manner the same is to be performed, and to cause the same to be inrolled
in His said Majesty's High Court of Chancery within two calendar months
next and immediately after the date of the said recited Letters Patent, as in
and by the same, reference being thereto had, will more fully appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
David Mushet, do hereby describe and ascertain the nature of our said Inven-
tion or improvement, and in what manner the same is to be performed, as
follows; that is to say :-
It has been long known that certain refuse slags or cinders produced in the
smelting of copper ores and in the manufacture of copper, commonly denomi-
nated ore furnace slags and metal furnace or sharp slags, do contain, along
with a portion of copper, a considerable portion of iron; but though such slags
or cinders have at different times been subjected to process for the purpose of
extracting therefrom the copper which they might contain, they have not
hitherto been operated upon for the purpose of bringing the iron contained
therein into a state fit for any of the purposes to which pig iron is applicable,
as far as it regards the manufacture of bar or other malleable or ductile iron.
The recovery of the said iron, and the bringing the same into a state fit for those
various purposes, is the object and intention of our said Invention or improve-
ment. And we have ascertained that the said slags or cinders, when properly
smelted in the blast furnace, may, by following the instructions herein-after
mentioned, and by the common and ordinary processes of refining, stamping,
puddling, balling, hammering, reheating, rolling, slitting, or other well known
processes, be converted into finer's metal, stamped iron, paddling iron, bloom
iron, bar iron, rod iron, and other sorts of malleable or ductile iron. But
inasmuch as the said refuse slags or cinders contain certain quantities or pro-
portions of copper, as above said, or other metal or metals, which, when
existing beyond a certain proportion, are injurious to the quality of the said
bar or other iron that may be extracted therefrom, we are careful to select and
arrange the said slags or cinders previously to smelting accordingly; and as we
find the quantity of copper in the said refuse slags or cinders to be more or
less, we smelt the same in the blast furnace with limestone, in the usual
method of making pig iron, and add to the said slags or cinders certain quan-
tities or proportions of iron stones, iron ores, or other substances containing
iron (increasing the quantity of the said ironstones or other substances con-
taining iron in proportion to the larger quantity of copper which may be
contained in the said slags or cinders under process, or diminishing the quantity
of the said ironstones or other substances containing iron when the said slags
or cinders contain a comparatively small quantity of copper), till we obtain a
quality of mixed fusible metal capable of being refined and worked by the
processes now in use into bar or other useful malleable or ductile iron. And
we have further ascertained, by experiment on the scale of manufacture, that
as a general rule bar or other malleable or ductile iron may be manufactured
from pig or cast iron coutaining three parts of metal produced from the said

page_text: slags or cinders and one part of cast iron produced from ironstones or other
substances containing iron, employed in mixture with the said refuse slags or
cinders. But this proportion it will be found necessary at times to vary,
according to the quantity of the copper or other metal or metals in the said
slags or cinders made use of; and under every circumstance we prefer making
the said mixed fusible metal by smelting the slags or cinders and ores and
other substances containing iron together in the blast furnace (having pro-
viously ascertained the quantities of iron in them respectively) to making a
mixed and fusible metal directly from the said slags or cinders, and then
mixing this fusible metal, when so obtained, with pig iron obtained from iron-
stones, iron ores, or other substances containing iron. And as we consider it
of advantage to introduce the said refuse slags or cinders in the blast furnace
in as small masses as may be conveniently obtained, we either reduce the same
by any mechanical power in use, or we melt the said slags or cinders in an air
or other furnace, and run them out in smaller masses; or we granulate the
same by running them, while fluid, into water. It may be proper further to
remark, that in smelting the said mixed metal (which, however, is chiefly iron)
from the said refuse slags or cinders, a larger quantity of lime is required as a
flux than in the smelting of iron directly from ironstones or other iron ores,
and that with such variety of slags as we have hitherto operated upon, we have
found that a quantity of limestone from three eighths to six eighths, by weight,
of the slags or cinders is required to reduce the metal in a proper state for the
subsequent operation, those slags which are poorest in metal requiring the
largest dose of lime or limestone.
In witness whereof, I, the said David Mushet, have hereunto set my
hand and seal, this Thirteenth day of June, in the year of our Lord