IMPROVEMENTS IN THE MANUFACTURE OF STEEL
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF STEEL." A communication from abroad by William
Fields, of Wilmington, in the County of New Castle, State of Delaware,
United States of America.
Sealed the 8th August 1876, and dated the 9th March 1876.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 9th March 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
IMPROVEMENTS IN THE MANUFACTURE OF STEEL."
"1
This Invention consists in the combinations of chemical compounds herein-after
described, one of which is first mixed with the iron in the boiling or puddling
furnace while in a thoroughly molten state, and thoroughly incorporated with it by
stirring for decarbonizing, desulphurizing, and dephosphorizing the iron, after which
the furnace is closed for a few moments to allow the escape of the disengaged
sulphur, phosphorus, and carbon, when it is again opened and the second compound
is put in and quickly stirred into the molten mass of cinder and iron, after which the
damper is kept open a sufficient time to recarbonize and alloy the iron, and thus
form steel of any desired quality.
To nine hundred and fifty pounds of pig iron made from charcoal or anthracite
and fifty pounds of franklinite iron I put in for removing the sulphur, phosphorus,
and other impurities (the iron being in a molten state in the boiling or puddling
furnace) half a pound of litharge, half a pound of sal soda, half a pound of sal
ammoniac, half a pound of saltpetre, half gallon of fine charcoal, and stir well for
two or three minutes to work off the impurities. Then for the second compound I
put in four pounds chromate of iron, one pound black oxide of manganese, one pound
antimony, one pound wolfram, one pound sal ammoniac, one pound litharge, and
two pounds York ore, and stir well; hammer two or more balls together, then heat
again, and roll into rails or other articles.
I do not confine myself to the exact proportions of the several chemicals men-
tioned for this reason that it depends upon the quality of the iron used as to whether

page_text: the proportions should be greater or smaller than above stated, or whether it is
necessary to use all of them to obtain the result. This must depend upon the
For instance,
operator, who is supposed to know the quality of the iron he uses.
when the iron is very poor and difficult to fuse, I should use the franklinite in
greater proportion, also more of the sal ammoniac and more of the chromate of iron,
according to circumstances.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the 9th
August 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
"IMPROVEMENTS IN THE MANUFACTURE OF STEEL." A communi-
cation from abroad by William Fields, of Wilmington, in the County of New
Castle, and State of Delaware, United States of America.
This Invention consists in the combinations of chemical compounds herein-after
described, one of which is first mixed with the iron in the boiling or puddling
furnace while in a thoroughly molten state, and thoroughly incorporated with it by
the stirring, for decarbonizing, desulphurizing, and dephosphorizing the iron, after
which the furnace is closed for a few moments to allow the escape of the disengaged
sulphur, phosphorus, and carbon, when it is again opened, and the second compound
is put in and quickly stirred into the molten mass of cinder and iron, after which
the damper is kept open a sufficient time to recarbonize and alloy the iron, and thus
form steel of any desired quality.
To nine hundred and fifty pounds of pig iron made from charcoal or anthracite
and fifty pounds of franklinite iron I put in for removing the sulphur, phosphorus,
and other impurities, the iron being in a molten state in the boiling or puddling
furnace, half a pound of litharge, half a pound of sal soda, half a pound of sal
ammoniac, half a pound of saltpetre, half gallon fine charcoal, and stir well for two
or three minutes to work off the impurities. Then for the second compound I put
in four pounds chromate of iron, one pound black oxyde of manganese, one pound
antimony, one pound wolfram, one pound sal ammoniac, one pound litharge, and two
pounds York ore, and stir well, hammer two or more balls together, then heat again,
and roll into rails or other articles.
I do not confine myself to the exact proportions of the several chemicals men-
tioned for this reason, that it depends upon the quality of the iron used as to whether
the proportions should be greater or smaller than above stated, or whether it is
necessary to use all of them to obtain the result. This must depend upon the
For instance,
operator, who is supposed to know the quality of the iron he uses."
when the iron is very poor and diflicult to fuse, I should use the franklinite in
greater proportion, also more of the sal ammoniae, and more of the chromate of iron,
according to circumstances,
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is,-
First. The process of treating iron during the puddling or boiling process for the
purpose of converting it into steel with a chemical compound composed of the
ingredients herein-before first named in the manner substantially as and for the
purpose set forth, the saine being the compound first used in the process.
Second. The process of treating iron for the purpose of converting it into steel
during the puddling process with a chemical compound composed of the ingredients
herein-before last mentioned in the manner substantially as set forth, the same being
the compound used in the latter part of the process.

page_text: Third. The whole process of treating iron for the purposes aforesaid, as herein-
before fully set forth and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Ninth day of August, in the year of our Lord One
thousand eight hundred and seventy-six.
A. M. CLARKE. (LS.)