That was the benefaction of the trade;
but what was the benefaction of the
government? Twenty-five pounds six
shillings was a pension granted by King George
the Fourth's warrant to Cort's daughters as
a pension. An arbitrary deduction was,
however, made—no doubt, by an economical
ministry of George the Fourth's virtuous
days—and, for the fifteen years following,—
eighteen hundred and sixteen,—the sum
actually paid out by the Exchequer was
twenty pounds. But, of this sum, a clerk in
the Exchequer put one pound a-year into his
pocket as his own fee for the trouble he took
in transmitting it. In the days of William
the Fourth it was righteously ordained that
pensions should be made without deduction;
new warrants were made out, and the clerk
no longer received a pound for paying nineteen
pounds to an inventor's daughter. She
received her nineteen pounds without any
such mean deduction. The subtracted pound
was pocketed, not by an Exchequer clerk, but
by the British nation. Two of Mr. Cort's
daughters survive, and two pounds a-year is
the national saving made at their expense by
the impartial and dignified economy of our
official system.
Now, it is a singular fact, that the awakening
of the public to a sense of the ill-usage
suffered by the founder of our iron constitution
is contemporary with the beginning of
another great advance in strength. A new
inventor has arisen in these days: seventy
years having elapsed since Cort's establishment
of the British manufacture of wrought
iron, and no improvement having been made
during this interval on either of his processes.
Valuable as they have proved, they are
both complex and troublesome, as we shall
show presently, when we explain them at
more length; an improvement was in the
natural course of things quite due, or even
over-due: and it has come during the last
month or two in the shape of a process
patented by Mr. Bessemer, the publication of
which (if it fulfil only one half of the just
expectation it has raised) will be probably to
this country the most important event of the
year 'fifty-six. Mr. Bessemer's process
supersedes the puddling furnace. One of the cupels
in which he converts cast iron into malleable
iron and steel, will produce, he declares, in a
day as much malleable iron as fifty
puddling furnaces, and that too, with but a
hundredth part of the labour. But, while
the puddling furnace may be superseded, the
grooved roller rises into fresh importance.
Before we proceed any farther, let us
endeavour to tell in a sentence or two, how the
iron manufacture is at present carried on.
The ore is first made into heaps with coal,
and burnt or roasted. Water and carbonic
acid are thus driven off, and there is left a porous
mass of impure oxide of iron, with all the
earthy matter that was not to be volatilised.
To get rid of the oxygen, which makes an
oxide of the iron, and to get rid, also, of the
earthy matter, are, of course, the two next
objects of the manufacturer. Charcoal (carbon),
burning at a white heat, has a thirst
for oxygen wholly unparalleled. It burns
the faster for the oxygen it drinks, becomes
the hotter, and increases in its thirst. Lime
added to the earthy matters in the roasted
iron unites with them at a white heat, causing
them to melt and rise in a thick scum.
Let, therefore, the roasted ore be burnt in
huge furnaces with lime and charcoal, while
the entire mass is urged to a white heat by
mighty blasts of air; and the glowing charcoal
will suck oxygen out of the iron, and
reduce this from the state of oxide to a more
surely metallic mass. The metal so reduced
will sink by its own weight below the scum
formed by the union of the earthy matter
with the lime. This is the work done in the
blast furnaces, from the bottom of which
molten iron runs, while the scum, or slag, is
drawn off from an upper opening: fresh
charcoal, lime, and roasted ore, being
continually poured in at the top, to feed the
furnace.
We have said that charcoal is used in this
process of reduction. It is used only where
it can be got in quantity sufficient, and, as it
is the parent form of carbon, where it can be
used much trouble is spared in later
processes. It is because our power of using
charcoal, is, in this country, very limited, that
we were obliged to look to Sweden and to
Russia for good working iron, before Cort
taught us how to make coke serve our turn.
But, even now for certain qualities of iron,
as for that which is made into wire, we are
obliged commonly to go to Sweden.
We use coke then, and not charcoal, in
our blast furnaces; the coke, of course,
containing mineral impurities, many defects
occur in the iron, which runs in a molten
stream out of the bottom of the furnace.
It runs along channels of sand on the floor
of the furnace-house into rough moulds,
wherein it cools down into masses of the
metal which, as it now stands, contains in
small proportions a variety of foreign
matters—silicon, sulphur, phosphorus, with
traces of aluminum, calcium, and potassium.
This is pig-iron.
The pig (or cast) iron is little fit for use.
To make it valuable in the arts, it must be
made malleable, and almost, or quite,
converted into steel. To convert pig-iron into
steel, it is requisite to get rid of as much
impurity as possible, and to reduce the quantity
of carbon it contains. A main difference
between iron and steel is, that the steel
contains less carbon.
Our narrative will be the clearer, if we
say, at once, that Mr. Bessemer proposes to
do, by a single process, what is done now by
the successive steps we are about to count.
He does not even go so far with the old
process as we have already described. He does
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