A NEW METALLIC ALLOY
Year: 1860

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of 166, Buchanan Street, in the
City of Glasgow, North Britain, Gentleman, for the Invention of "A
NEW METALLIC ALLOY."-A communication from abroad by Messieurs
Charles Noel and Company, of Paris, in the Empire of France,
Metallurgists.
Sealed the 4th October 1860, and dated the 5th April 1860.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 5th April 1860.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North Britain,
Gentleman, do hereby declare the nature of the said Invention for * A NEW
METALLIC ALLOY," a communication from abroad by Messieurs Charles Noel.
and Company, of Paris, in the Empire of France, Metallurgists, to be as
follows:-
This Invention relates to the production or manufacture of a new metallic
alloy, which is easily melted, and when cast forms a species of cast steel,

page_text: capable of being substituted for ordinary steel, and consequently when used in
the construction of machinery obviating to a great extent the use of forgings.
The principal bases of this alloy are wrought iron and cast iron, the proportions
of which are varied according to the degree of hardness required. To the
bases above mentioned are added oxidised iron ore, free from sulphur, 5
manganese, nitrate of potash, and chlorhydrate of ammonia. These various
ingredients may be used in various combinations and proportions, according to
the required degree of hardness of the alloy to be produced.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on the
5th October 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, and
of 166, Buchanan Street, in the City of Glasgow, North Britain, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of April, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-third year of Her
reign, did, for Herself, Her beirs and successors, give and grant unto
me, the said John Henry Johnson, Her special license that I, the said
John Henry Johnson, my executors, administrators, and assigns, or such
others as I, the said John Henry Johnson, my executors, administrators, or
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 "A NEW METALLIC ALLOY," a communication from abroad by Messieurs
Charles Noel and Company, of Paris, in the Empire of France, Metallurgists,
upon the condition (amongst others) that I, the said John Henry Johnson,
by an instrument in writing under my hand and seal, 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.

page_text: NOW KNOW YE, that I, the said John Henry Johnson, 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, that is to say:-
The said Invention relates to the production of a metallic alloy which has
the properties of cast steel, which rendering it capable of being substituted for
ordinary steel, and as its cost is much reduced, it may be applied in all cases
where expensive forging work is now employed. The bases of this alloy are
wrought iron and cast iron of any quality, melted together in suitable propor-
tions, to give to the alloy so obtained the desired amount of carbon, according
to the degree of hardness required in the alloy. In relation to steel it is well
known that wrought iron contains less carbon, and pig iron an excess of
carbon. Now, by alloying with the wrought iron (which is in a sub-car-
bonized state) just so much pig metal (which is in a super-carbonized state) as
will give to the alloy the per-centage of carbon required to make cast steel of
any desired degree of hardness (the free carbon and impurities being extracted
as herein-after described), a product will be obtained having all the properties
of cast steel with the other advantages herein-before mentioned. The greater
the proportion of pig metal employed the harder will be the alloy, and vice
versa. I have found in practice that fifteen per cent.. of pig metal will
produce in my soft alloy twenty-five per cent., a good medium quantity, and
so on, care being taken to vary these proportions in accordance with the more
or less carbonized state of the wrought iron, as it is obvious that a highly
carbonized iron will require less pig metal than a less carbonized variety to
produce an alloy of a given degree of hardness.
In preparing this alloy according to my Invention, I take any iron without
regard to its state of purity, and after ascertaining the extent of its impurities,
I introduce into the crucible or melting pot a combination of certain chemicals
herein-after referred to, which by their affinity for the impurities will extract
them, and leave the metal pure.
The production of the alloy and the requisite purification of the iron are
effected at one operation in an ordinary furnace and melting pots, and the
use of cementing furnaces is entirely dispensed with.
Although the foulest iron may be employed, yet as this necessitates the use
of a large charge of chemicals, which would tend to destroy the melting pots,
I prefer to use an ordinarily clean English, Scotch, or Welch iron, such as
can be bought, say, at about eight pounds per ton, and grey pig metal of the
like description, at, say, about three pounds per ton. I should, however,
recommend a highly carbonized iron, as it melts more easily, but when such

page_text: cannot be obtained, the fusing may be assisted by the addition of a small
quantity of charcoal. The wrought iron to be melted is now cut up into
suitable pieces, and the pig metal broken up so as to be easily introduced into
the crucible or melting pot, the proportions of each being varied according to
the carbon they contain, and the hardness of the alloy required, as herein-
before described. It will be found advantageous in practice to add the pig
metal (having previously heated it) to the wrought iron after the first furnace
charge has burnt down, as the pig metal fuses more rapidly than the wrought
iron. When the alloy has assumed the state of dough or become a pasty mass,
the requisite purifying chemicals and fluxes may be added. The combination
of chemicals which I propose to use consists of oxide of manganese, sesqui-
oxide of iron or mineral oxide, well purified from sulphur, sal ammoniac, and
nitrate of potash, in suitable proportions, varying with the more or less impure
state of the iron. For such iron as I have herein-before mentioned as being
most suitable, the following proportions will be found to answer for a crucible
containing forty pounds of alloy; say, half a pound of oxide of manganese, a
quarter of a pound of oxide of iron, and three ounces each of sal ammoniac
and nitrate of potash. In treating very impure iron, these quantities may be
doubled, but for the finer sorts of iron four ounces of each of the oxides and
two and a half ounces of each of the salts will be found sufficient. According
to the nature of the impurities so will the above proportions be varied, as, for
example, as the iron contains more or less of earthy matters, so will the
proportion of oxide of iron be increased or diminished, the same remark
applying equally to the salts in relation to the quantity of phosphorous, sulphur,
and other similar impurities contained in the iron. If desired, a small
quantity of the metallic oxides, or other well-known chemicals which are
believed to produce beneficial results, may be added to the alloy, but I have
found in practice that their presence is not necessary.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion that what I consider to be novel and
original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent, is,-
First, the production of an alloy having the properties of cast steel by
melting together wrought iron and pig metal of any quality, and in suitable
proportions, in an ordinary crucible, wherein the processes of melting, con-
verting, and purifying the substance under treatment are effected at one
operation, as herein-before described.
Second, the application and use to and in the production of alloys composed

page_text: of wrought iron and pig metal of a combination of the oxides of manganese
and of iron with sal ammoniac and nitrate of potash for the purpose herein-
before described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, this Fifth day of October, One thousand eight
hundred and sixty.
J. HENRY JOHNSON. (L.S.)
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