AN IMPROVED PROCESS FOR HARDENING MALLEABLE AND NON-MALLEABLE CAST IRON
Year: 1865

page_text: LETTERS PATENT to William Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for
the Invention of "AN IMPROVED PROCESS FOR HARDENING MALLEABLE AND
NON-MALLEABLE CAST IRON."-A communication from abroad by Thomas
Henry Jenkins, of the City and State of New York, in the United
States of America.
Sealed the 9th January 1866, and dated the 17th November 1865.
PROVISIONAL SPECIFICATION left by the said William Edward Newton,
at the Office of the Commissioners of Patents, with his Petition, on
the 17th November 1865.
I, WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Civil Engineer, do hereby declare the
nature of the said Invention for "AN IMPROVED PROCESS FOR HARDENING
MALLEABLE AND NON-MALLEABLE CAST IRON," to be as follows:-
The object of this Invention is to render malleable and non-malleable
cast iron tough and hard as hardened steel, so that it may be used for
many of the purposes for which steel has heretofore been employed. The
pieces of iron to be hardened (of whatever shape and size, and either
rough or after they have been filed and smoothed) are heated to a
temperature known as cherry red, and hammered to compact the metal.
After this they are heated again to a cherry-red heat, and then taken out

page_text: of the fire; a pulverized preparation composed of seven parts by weight
of prussiate of potash and one part by weight of charcoal is sprinkled on
the surface. The iron is put in the fire again until this composition
disappears, but taking care to raise the temperature again to a cherry-red
heat; it is then plunged in a liquid bath composed of about twenty-eight
gallons of water, eight pounds of oil of vitriol, forty-four ounces of sal-
ammoniac, twenty ounces of glauber salts, and thirty ounces of common
or table salt. When taken from this solution it will be found that the iron
has become very tough and hard, and sufficiently hard for axes, hatchets,
and tools of that class. For the shares and other parts of ploughs, and
for other articles that require to be hard, but in which a keen cutting edge
is not necessary, prussiate of potash may be dispensed with.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Edward Newton in the Great Seal Patent
Office on the 16th May 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventeenth day of November, in the year
of our Lord One thousand eight hundred and sixty-five, in the twenty-
ninth year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Edward Newton, Her special licence, that
I, the said William Edward Newton, my executors, administrators, and
assigns, or such others as I, the said William Edward Newton, 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 IMPROVED PROCESS FOR
HARDENING MALLEABLE AND NON-MALLEABLE CAST IRON," being a communi-
cation from abroad, upon the condition (amongst others) that I, the said
William Edward Newton, 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

page_text: 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 I, the said William Edward Newton, 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):-
What is termed in the arts malleable iron is cast iron which by a well-
known process is rendered comparatively malleable, that is to say, it loses
the brittleness which is one of the characteristics of cast iron, and it may
be bent and hammered, although not to the same extent as wrought iron,
and it can be filed and turned with comparative facility. The object
of the present Invention is to render malleable and non-malleable cast iron
tough and hard as hardened steel, so that it may be used for many of the
purposes for which steel has heretofore been employed and at much less
cost. To this end the pieces of iron to be hardened (of whatever shape
and size, and either rough or after they have been filed and smoothed), are
heated to about a cherry-red temperature, and are then hammered to
compact the metal.
After this they are heated again to a cherry-red heat,
and then taken out of the fire. A pulverized preparation composed of
seven parts by weight of prussiate of potash and one part by weight of
charcoal is then sprinkled on the surface. The iron is then put in the fire
again until this composition disappears, but taking care to raise the
temperature again to a cherry-red heat. The iron is then plunged in a
liquid bath composed of about twenty-eight gallons of water, eight pounds
of oil of vitriol, forty-four ounces of sal ammoniac, twenty ounces of
glauber salts, and thirty ounces of common or table salt. The quantity to
be used will of course depend on the size of the articles to be hardened.
When taken from this solution it will be found that the iron has become
very tough and hard, and sufficiently hard for axes, hatchets, and tools of
that class. For the shares and other parts of ploughs, and for other articles
that require to be hard, but in which a keen cutting edge is not necessary,
the prussiate of potash may be dispensed with.
Having now described the Invention of an improved process for hardening
malleable and non-malleable cast iron, as communicated to me by my foreign
correspondent, and having explained the manner of carrying the same into
effect, I claim as the Invention secured to me by Letters Patent as aforesaid,
the process herein set forth and described for hardening malleable and
non-malleable cast iron by plunging it while at or about a cherry-red heat
in a chemical solution as herein described. And I also claim in combination

page_text: with and preparatory to the hardening in a solution as herein described, the
treatment of the iron in a heated state with a composition of prussiate of
potash and charcoal as herein described.
In witness whereof, I, the said William Edward Newton, have hereunto
my hand and seal, this Fourteenth day of May, in the year of
our Lord One thousand eight hundred and sixty-six.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)