IMPROVEMENTS IN THE MANUFACTURE OF CAST STEEL AND IN THE RE-MANUFACTURE OF OLD STEEL
Year: 1860

page_text: LETTERS PATENT to Charles Cowper, of No. 20, Southampton Buildings,
Chancery Lane, in the County of Middlesex, Patent Agent, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF CAST STEEL AND IN
THE RE-MANUFACTURE OF OLD STEEL."-A communication from abroad by
Louis Jules Duhesme, Henri Catherine Camille de Ruolz, and Anselme
Louis Marie de Fontenay, all residing at Paris, in France.
Sealed the 7th February 1861, and dated the 7th September 1860.
PROVISIONAL SPECIFICATION left by the said Charles Cowper at the
Office of the Commissioners of Patents, with his Petition, on the 7th
September 1860.
I, CHARLES COWPER, of No. 20, Southampton Buildings, Chancery Lane,
in the County of Middlesex, Patent Agent, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF CAST STEEL AND
IN THE RE-MANUFACTURE OF OLD STEEL," to be as follows:-
In making cast steel according to this Invention, certain mixtures of
wrought iron, cast iron, oxide of iron, old steel, and ferrocyanide of potassium,
or ferricyanide of potassium, or some of them, are to be employed. The ferro-
cyanide of potassium is commonly known as yellow prussiate of potash, while
the ferricyanide of potassium is commonly known as red prussiate of potash.
The corresponding sodium salts may be substituted for the potassium salts.
Thus, one mixture consists of 700 parts by weight of wrought iron, 200 parts.
of white cast iron, 100 parts of oxide of iron, and 8 parts of red prussiate of
potash. A second mixture consists of 500 parts of old steel, such as old files,
tools, or springs, 500 parts of wrought iron, and 14 parts of red prussiate of
potash. A third mixture consists of 350 parts of old steel, 350 parts of

page_text: wrought iron, 200 parts of white cast iron, 100 parts of oxide of iron, and
7 parts of red prussiate of potash. A fourth mixture consists of 1,000 parts
of wrought iron, 75 parts of oxide of iron, and 28 parts of red prussiate of
potash or ferricyanide of potassium.
If the yellow prussiate of potash is employed, a quantity double that
indicated for the red prussiate should be used; but the red prussiate is con-
sidered to be preferable. Refined iron or fine metal may be advantageously
substituted for the cast iron, using a double quantity without altering the
proportion of prussiate. The cast iron should be white, and it is advantageous
to employ two or more different sorts or qualities, one of which should contain
manganese. The cast iron is to be broken up into small fragments. The
wrought iron ought to be in pieces as small as possible; and it is advantageous
to employ two or more varieties, but of a similar quality. The mixture of
fibrous and granular irons should be avoided. Granular iron of good quality
is to be preferred. The old steel ought to be of good quality, and in small
fragments.
Another mixture consists of 1,000 parts of old steel, such as old files, tools,
and springs, with 10 parts of red prussiate of potash, or 20 parts of yellow
prussiate of potash.
The above proportions are given as examples, but they admit of modifi-
cation. Instead of the prussiates, materials capable of producing or liberating
them may be substituted. The aforesaid materials being intimately mixed
together are heated in covered crucibles until they are completely melted, and
the resulting cast steel is poured out as usual. Plumbago or graphite
crucibles, or the ordinary crucibles used for melting steel, inay be employed.
In using graphite crucibles it is well to increase the proportion of prussiate a
little after the crucibles have been used two or three times. The melting
furnace may be heated by very pure coke, to which about a tenth part of wood
charcoal may be added with advantage.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by Edward Alfred Cowper, of 354, Great George Street, West-
minster, and Richard Anthony Thompson, of 1, Hornton Villas, Ken-
sington, Executors of the last Will and Testament of the said Charles
Cowper, deceased, in the Great Seal Patent Office on the 6th March
1861
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by Edward Alfred Cowper, of 354, Great George Street, West-
minster, and Richard Anthony Thompson, of 1, Hornton Villas, Ken-
sington, Executors of the last Will and Testament of the said Charles
Cowper, deceased, in the Great Seal Patent Office on the 6th March
1861
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, EDWARD
ALFRED COWPER, of 35, Great George Street, Westminster, and RICHARD

page_text: ANTHONY THOMPSON, of 1, Hornton Villas, Kensington, Executors of the last
Will and Testament of CHARLES COWPER, of No. 20, Southampton Buildings,
Chancery Lane, in the County of Middlesex, Patent Agent, who departed
this life on or about the Twenty-third day of December, One thousand eight
hundred and sixty, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of September in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto the said
Charles Cowper, Her special licence that he, the said Charles Cowper, his
executors, administrators, and assigns, or such others as he, the said Charles
Cowper, his 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 CAST STEEL AND IN THE RE-MANUFACTURE OF OLD STEEL," a
communication to him from abroad by Louis Jules Duhesme, Henri Catherine
Camille de Ruolz, and Anselme Louis Marie de Fontenay, all residing at
Paris, in France, upon the condition (amongst others) that he, the said
Charles Cowper, his executors or administrators, by an instrument in writing
under our or their hands and seals, or under the hand and seal of one of us or
them, should particularly describe and ascertain the nature of the said Inven-
tion, 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 we, the said Edward Alfred Cowper and Richard
Anthony Thompson, as such executors as aforesaid, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
The improvements consist in mixing certain proportions of either the whole
or some of the following ingredients, namely, wrought iron, cast iron, oxide of
iron, and old steel with either ferricyanide of potassium, commonly known as
red prussiate of potash, or with ferrocyanide of potassium, commonly known
as yellow prussiate of potash, acting as reagent, some of these mixtures being
intended for the manufacture of cast steel, and others being intended for the
remanufacture of old steel.

page_text: Thus, for the manufacture of cast steel, one mixture employed consists of-
Wrought iron
White cast iron
Oxyde of iron
700 parts by weight.
-
200 ditto
ditto.
-
100 ditto
ditto.
Red prussiate of potash
A second mixture consists of
Old steel (old files, tools, or springs)
Wrought iron
-
Red prussiate of potash
A third mixture consists of-
Old steel
Wrought iron
White cast iron
Oxide of iron
Red prussiate of potash
A fourth mixture consists of-
Wrought iron
Oxyde of iron
Red prussiate of potash
-
8 ditto ditto.
500 parts by weight.
500 ditto
14 ditto ditto.
ditto.
350 parts by weight.
350 ditto ditto.
200 ditto ditto.
100 ditto ditto.
7 ditto ditto.
1,000 parts by weight.
75 ditto
28 ditto
ditto.
ditto.
If yellow prussiate of potash is employed instead of the red prussiate
potash in the mixtures herein-before described, double the quantity indicate
for the red prussiate of potash is used; but the latter is preferred as giving
more decided reaction, and also on account of its containing no water
crystallization. Refined iron or fine metal may be advantageously substituted fo
the cast iron in the first and third mixtures, in which case the quantity of fin
metal employed must be double that indicated for the cast iron, without alterin
he proportions of red prussiate of potash. The cast iron employed should b
white, and of at least two qualities, one of which should contain manganes
It is to be first broken up into small fragments. The wrought iron shoul
be in the smallest possible fragments, and it should be avoided to use granula
with fibrous iron. Granular iron of a good quality is preferred. The old stee
should be of a good quality, and introduced into the mixture in small pieces.
For the remanufacture of old steel, one mixture employed consists of―
Old steel, such as old files, tools or springs 1,000 parts by weight.
Red prussiate of potash
-
Another mixture consists of -
10 ditto ditto.

page_text: The use of red prussiate of potash is preferred to that of the yellow prussiate
of potash, as giving a more decided reaction, and containing no water of
crystallization.
In operating the manufacture of cast steel, as also the remanufacture of
old steel, according to this Invention, the above mixtures have to be melted
down in crucibles, the ingredients having been previously mixed as completely
as possible. The old steel, as also the wrought and cast iron, should first be
broken into small pieces, and the prussiate of potash should be well distributed
throughout the mass. The operations take place in a common air furnace,
for which a very pure coke is employed, mixed with a tenth part of wood
charcoal. The crucibles must be kept hermetically closed until complete
fusion of the metals ensues, and the fire must be managed with the usual
precautions. The same description of crucibles is employed as is generally
used for the smelting of steel. Those of plumbago are preferred, but if these
are used it is well to increase slightly the proportion of prussiate of potash
after the crucibles have been employed for two successive smeltings.
Having now described the nature of the said Invention, and in what
manner the same is to be performed, we wish it to be distinctly understood
that what we claim is, the use of all such mixtures as berein-before described
for the manufacture of cast steel, or for the remanufacture of old steel, wherein
either red prussiate of potash or yellow prussiate of potash, or their constituents,
are used as reagents.
In witness whereof, we, the said Edward Alfred Cowper and Richard
Anthony Thompson, have hereunto set our hands and seals, this Fifth
day of March, in the year of our Lord One thousand eight hundred
and sixty-one.
EDWARD ALFRED COWPER. (L.S.)
RICHARD A. THOMPSON.
(L.S.)