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not let the molten metal coming from the
blast-furnace cool into pig-iron, and allow the
manufacturer to go to the expense of a fresh
melting. As it flows white hot from the
blast-furnace, he receives the cast metal by a
trough, into his cupel, or refining-pot, where
he arrestsand shows evidence to prove
that in half-an-hour, and by a single process
which one man can conduct, all is done,
cheaply, easily, and rapidly, that is now done,
at considerable cost of time, labour, and
money in the manner following:

The impurities in the cast iron are got rid
of, as far as possible, by again melting it and
exposing it while molten to the action of the
air. For, these impurities are all of a kind to
unite at a high temperature with the oxygen
of which air is in part composed, and the
oxygen compounds so formed are either
volatile, or easily fusible, and unable to
combine with the metallic iron. The carbon left
in the iron of course takes the same
opportunity of uniting itself with oxygen, burns
itself off, and so diminishes its quantity. It
was proposed, therefore, that the metal again
melted should be exposed as much as possible
to contact with the air. This was done, first by
the refining, then by puddling. These two
processes occasion two separate heatings followed
by two more coolings of the metal. In the
refinery the metal fusedwith charcoal, if a
superior result, or charcoal iron, is desired
is brought into contact with air sufficiently
to burn off more of its charcoal, and to form
a second finer slag, chemically reducible to
the ingredients of flint and iron.

Then begins the puddling. The iron again
melted on the bed of a reverberatory
furnace, is vigorously stirred by hand-labour
with a long rod, in order that it may be as
much as possible touched by the air. As
the carbon is burnt off by absorption of the
oxygen, the whole mass ceasing to be fluid,
becomes dense and spongy. Then the puddler,
standing almost naked at the furnace, collects
on the end of his rod as much of the thick
iron paste as he can lift, and, swinging it
through the air, places it under a forge-
hammer, by which it is crushed and kneaded
as it cools before passing along the grooves of
the roller, within which it is finally drawn
out and compressed. The iron passed through
a broad groove, has sometimes to be again
heated before it will pass through another
that is narrower. In the course of purifying,
beating, rolling, cutting, and welding, the
best iron has to be heated six times over, at
great cost of fuel, time, and toil. By this
new process it is not to cool once, till the
manufacture is complete. There is a great
saving of fuel, and the smallest possible
expense of time and labour.

In the very brief sketch that has here
been given, the reader may have observed
the laborious nature of the puddling process,
and the somewhat clumsy method of exposing
liquid metal to the air by causing it to be
stirred up with a long pole. Mr. James
Nasmyth suggested that strong jets of steam,
forced into the liquid metal from below (care
being taken that it was in full rush before the
metal entered), would throw the whole mass
into agitation, and be an efficient substitute,
so far as stirring went, for the rod of the
puddler. Steam would do nothing more than
reduce the temperature of the metal. Nobody
has been more prompt than Mr. Nasmyth to
declare that quite another principle is
involved, and a far happier suggestion made, when
Mr. Bessemer says, Don't throw up jets of
steam, but jets of cold air. That is the whole
gist of Mr. Bessemer's suggestion. In theory
and practical result the two ideas are as wide
asunder as A from Z, but independent people,
if they happen not to reflect or to inquire,
are very likely to be of the same mind with
the English Government officials, heads of a
certain department at Woolwich, who, when
Mr. Bessemer made his suggestions known
to them some little time ago, pooh-poohed
them, and declined taking any benefits
therefrom;—the thing had been tried before,
they said, by Mr. Nasmyth. The Emperor
of the French, with quicker wit, has already
made up his mind to put the new plan to an
ample test, by introducing it into the arsenal
at Rouelle.

The whole point of Mr. Bessemer's invention
lies in the use of an air-blast, not only
to stir the iron in the pot, but to refine it.
It is no new discovery as to its principle; it
is a most happy adaptation of accepted
principles; a suggestion like almost every suggestion
that is of the highest value to the world,
marvellous clear and simple, as to which
people wonder why it has occurred to nobody
before. Possibly it may have been made by
others, as is the way also not seldom in such
cases; but it has never until now been
made so emphatically the possession of the
public as to ensure attention and acceptance,
if acceptance it deserve. It first took the
public by surprise in a paper read by the
patentee at the late meeting of the British
Association. In the paper it was explained
so distinctly, that there was universal admission
of the fact that, as to its theory, the new
plan is a sound one. It is declared, however,
by a large number of iron-masters, who are
not to be startled out of an accepted system,
that, for various technical reasons, known to
and stated by themselves, the new plan will
not work. They may be right; as we are
not without experience in this sort of prediction,
we also humbly venture to think that
they may be wrong.

Connect with the blast-furnace, says Mr.
Bessemer, a large cupola furnace lined with
fire-bricks to be the refining-pot; in the bottom
of it let there be the openings of pipes
through which blasts of air can be forced;
have a tap-hole stopped with loam, through
which the metal can be poured out at the
fitting time; and a hole halfway up, by