The Sun.
London, England, 1857-11-06 00:00:00

COMPLETION OF THE BESSEMBR

DISCOVERY.

When air, either coldor heated, is forced through
a molten mass of cast iron, the temperature of the
mass is rapidly raised, not so much by the com-
bustion of its combined carbon as by the deflagra-
tion of the iron itself ; and when the carbon has
been all or nearly all dissipated, the temperature
increases to an almost inconceivable extent, so that
the mass when containing only as much carbon as
is requisite to constitute with it cast steel, and even
when deprived of this small portion of carbon, and
existing in the state of semi-malleable iron, still
retains a perfect degree of fluidity. The announce-
ment of this fact is the sum and substance of Besse-
mer's discovery. Perfectly simple in itself, it had
been before the metallurgical world, both practical
and scientific, for centuries ; but it was reserved
fa. Bessemer to develope the principle to its fullest
extent ; and, in fact, though all the world knew
that heated iron would deflagrate in the air, with
lan intense generation of heat, no man but Besse-
mer had ever dreamed that blowing cold air
through melted iron, without the aid of additional
fuel, would raise the temperature of that iron to a
I degree never before witnessed in metallurgical ope-
rations. A more brilliant and surprising discovery
was never before published to the world. Let those
who cannot appreciate a great invention, and have
neither the energy, the talent, nor the perseverance
to carry it out, condemn this invention ; the inven-
tor may rest assured that it will one day be acknow-
ledged, and ranked, not with, but above the great
discoveries of Cort and Neilson. Bessemer's pro-
cess removes the carbon and silicon from the cast
iron operated upon, and when the blast is properly
adjusted, and a sufficient mass of metal is operated
upon, the waste need not exceed 20 per cent., the
remaining 80 per cent., being a kind of semi-malle-
able iron in a perfectly fluid state. When east ir.to
blooms or ingots, and cooled, it is found that, ac-
cording to the nature of the pig-iron from which
they have been prepared, these ingots possess
either a bright, crystalline, and cold short texture ;
or they present a granulated fracture, exhibiting
the cold, tough characteristics of the semi-steel de-
scribed by the late Mr. Mushet, at page 525 of his
work on iron and steel. In either case these ingots
prove hot-short when forged, and, except at a high
welding heat, they possess but little coherence. At
the welding heat they may be rolled or drawn into
bars, and these bars may be cut and piled, and be
then again drawn into bars ; but the original cha-
racteristics of the product are very slightly, if at
all, modified by these operations. Bessemer iron
is, therefore, not commercially valuable. The in-
ventor had succeeded in expelling the carbon and
silicon from cast iron, but the sulphur and phos-
phorus remained ; and, worse than these, a portion
of oxide of iron became diffused through the mass,
and imparted to it the inveterate hot short quality
which no subsequent operations could expel. In
other words, oxide of iron may be alloyed with
purified cast iron, whilst the latter retains its
fluidity, but cannot be removed or altered after the
iron has assumed the solid state ; so that in ope-
rating upon pig iron, which contained only small
doses of sulphur and phosphorus, the only hindrance
to the complete success of Bessemer's splendid dis-
covery was the presence of the disseminated oxide
of iron, and that a new oxide, not known or recog-
nised by chemists, who indeed, as a general rule,
know little or nothing about iron and its Protean
habitudes. Bessemer failed, however, to surmount
this seemingly trifling but really formidable obstacle,
and the consequence was, that though he had made
one stupendous step in advance of the whole me-
tallurgical and scientific world, he nevertheless lost
all credit, because he was unable to take the second
step toward complete success. He was. and I sup-
pose is still, condemned as a visionary schemer,
who has advanced a fallacious idea, and has failed
to carry it out. The Bessemer discovery being
thus, at least for a time, shelved and arrested in its
progress, it seems to have occurred to an individual
of the name of Mushet that if fluid metallic manga-
nese, with or without an accompanying alloy of
iron and carbon, could be presented to the fluid Bes-
seiner iron and alloyed therewith, whilst both re-
tained their fluid condition, that a portion of the
manganese thus alloyed would, from the powerful
affinity of that metal oxygen, unite with the
oxygen of the oxide of iron disseminated through
the fluid Bessemer iron, and pass off as slag, leav-
ing the mass free from the obnoxious oxide of
iron, and removing the hot short quality of the
iron. At the same time, by restoring a portion
of carbon to the purified mass, the mixture would
become steel, free from any red shortness, and
capable of being extended into sound and mar-
ketable bars. Mushet carried his ideas into prac-
tice, and with success. I have seen bars of steel
thus produced from coke pig iron which pos-
sessed incredible toughness, and from which tin
plates were made, of a quality superior to those
manufactured from the fumenit cakearoosl iron. The
blooms passed the rolls at the usual temperature
without a flaw or crack, and perfectly free from
blemishes. These tin plates, some of which I have
seen, were rolled by Mr. Thomas Allaway, the
eminent tinplate manufacturer at Lydney, a sta-
tion on the South Wales Railway. I have seen
also rattlers' tools, such as chisels, mandril points,
and hammers, made from this steel, and all of ex-
cellent quality, whilst the steel welds and works as
wFjll as the best double shear. Mushet patented his
discovery, and it has been before the public for Ulla
year or more ; and yet not one print, literary or
scientific, has condescended to notice it. So it lies a
spark amongst dry faggots, that will one day light
up a blaze which will astonish the world when the
unfortunate inventor can no longer reap the fruits
of his life-long toil and unflinching perseverance.
a say literally " light up a blaze," for when the
fluid metal from several blast furnaces is run into
one gigantic purifying chamber, and there purified
by high pressure blast forced through the molten
iron till the mass is oonverted into a seething leke
of liquid semi-malleable metal, the spectacle thus
presented will prove to be one of the grandest
sights ever witnessed, and when the semi-malle-
able but still crude metal shall receive its proper
dose of iron, carbon, and manganese poured into
it, from a separate blast furnace, and the crude
mixture shall at once becom'a, as by magic, oast
steel of excellent quality, then will the triumph of
the inventor's process be complete. Henry Bes-
semer will then get crcdit for his despised process,
and Robert Musket
will be reme.rabei ed for his in-
vention,
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Mechanics' 1:4-agazine.