The basic product of early ironmaking was
'pig iron'.
Pig iron was brittle in quality due to impurities and the nature of its
molecular structure and had to be converted into ' wrought iron ' by
re-heating and beating with heavy hammers to impart the strength and
tensile qualities required for more robust use.
An improved method of achieving this was ' puddling ' - the iron was
heated in a reverberatory furnace which was normally top heated, the heat
source not being in direct contact with the metal thus reducing
contamination.
In charge of this furnace was the ' Puddler ', a highly skilled and
dangerous occupation which required physical strength, stamina and
sustained concentration.
J.J.Davies, who was born in Tredegar but
emigrated to America where he later became a prominent figure in
Government, wrote an account of his early experiences as a puddler in his
book - "The Iron Puddler", recently republished.
"So those early iron
workers learned to puddle forge iron and make it into wrought iron which
is tough and leathery and can not be broken by a blow. This process was
handed down from father to son, and in the course of time came to my
father and so to me. None of us ever went to school and learned the
chemistry of it from books. We learned the trick by doing it, standing
with our faces in the scorching heat while our hands puddled the metal in
its glaring bath.
After melting down the pig-iron as quickly as possible, which took me
thirty minutes, there was a pause in which I had time to wipe the back of
my hand on the dryest part of my clothing (if any spot was still dry) and
with my sweat cap wipe the sweat and soot out of my eyes.
For the next seven minutes I "thickened the heat up" by adding
iron oxide to the bath. This was in the form of roll scale.
The furnace continued in full blast till that was melted. The liquid
metal in the hearth is called slag. The iron oxide is put in it to make it
more basic for the chemical reaction that is to take place.
Adding the roll scale had cooled the charge, and it was thick like
hoecake batter. I now thoroughly mixed it with a rabble which is like a
long iron hoe.
For twenty-five minutes
while the boil goes on I stir it constantly with my long iron rabble. A
cook stirring gravy to keep it from scorching in the skillet is done in
two minutes and backs off blinking, sweating and choking, having finished
the hardest job of getting dinner. But my hardest job lasts not two
minutes but the better part of half an hour.
My spoon weighs twenty-five pounds, my porridge is pasty iron, and the
heat of my kitchen is so great that if my body was not hardened to it, the
ordeal would drop me in my tracks.
Little spikes of pure iron like frost spars glow white-hot and stick out
of the churning slag.
These must be stirred under at once; the long stream of flame from the
grate plays over the puddle, and the pure iron if lapped by these gases
would be oxidized and burned up.
Pasty masses of iron form at the bottom of the puddle. There they would
stick and become chilled if they were not constantly stirred.
The whole charge must be mixed and mixed as it steadily thickens so that
it will be uniform throughout.
I am like some frantic baker in the inferno kneading a batch of iron
bread for the devil's breakfast."
The charge which I have
been kneading in my furnace has now "come to nature," the
stringy sponge of pure iron is separating from the slag.
The "balling" of this sponge into three loaves is a task that
occupies from ten to fifteen minutes. The particles of iron glowing in
this spongy mass are partly welded together; they are sticky and stringy
and as the cooling continues they are rolled up into wads like popcorn
balls.
The charge, which lost part of its original weight by the draining off of
slag, now weighs five hundred fifty to six hundred pounds.
I am balling it into three parts of equal weight. If the charge is six
hundred pounds, each of my balls must weigh exactly two hundred pounds.
I have always been proud of the "batting eye" that enables an
iron puddler to shape the balls to the exact weight required.
This is a mental act,--an act of judgment. The artist and the sculptor
must have this same sense of proportion. A man of low intelligence could
never learn to do it.
We are paid by weight, and in my time, in the Sharon mill, the balls were
required to be two hundred pounds. Every pound above that went to the
company and was loss to the men.
The balls are rolled up
into three resting places, one in the fire-bridge corner, one in the
flue-bridge corner, and one in the jam, all ready for the puddler to draw
them.
My batch of biscuits is now done and I must take them out at once and
rush them to the hungry mouth of the squeezing machine.
A bride making biscuits can jerk them out of the oven all in one pan. But
my oven is larger and hotter. I have to use long-handled tongs, and each
of my biscuits weighs twice as much as I weigh.
Suppose you were a cook with a fork six feet long, and had three roasting
sheep on the grid at once to be forked off as quickly as possible. Could
you do it?
Even with a helper wouldn't you probably scorch the mutton or else burn
yourself to death with the hot grease?
That is where strength and skill must both come into play.
One at a time the balls are drawn out on to a buggy and wheeled swiftly
to the squeezer. This machine squeezes out the slag which flows down like
the glowing lava running out of a volcano. The motion of the squeezer is
like the circular motion you use in rolling a bread pill between the palms
and squeezing the water out of it.
I must get the three balls, or blooms, out of the furnace and into the
squeezer while the slag is still liquid so that it can be squeezed out of
the iron.
From cold pig-iron to finished blooms is a process that takes from an
hour and ten minutes, to an hour and forty minutes, depending on the speed
and skill of the puddler, and the kind of iron.
I was a fast one, myself. But you expected that, from the fact that I am
telling the story.
The man that tells the story always comes out a winner."