Today, an old iron works hidden in the tall grass.
The University of Houston's College of Engineering
presents this series about the machines that make
our civilization run, and the people whose
ingenuity created them.
I turn into a rural New
Hampshire road. A driver on his way out says, "You
can't go in here; it's private." "I'm looking for
the old ironworks," I tell him. "Yes, that's on my
property," he answers. We chat for a bit. He sizes
me up. Then he says, "Go on up to the house. Tell
my wife I said you could go see it."
His wife takes me to a wall of underbrush and says,
"Go in and follow the bend of the river." I enter
with my arms lifted to avoid being scratched, and
plow ahead, unable to see in any direction but up.
I'm about to give up when the tall weeds part and a
structure like a decaying medieval castle magically
appears before me.
This was the first iron smelter in New Hampshire --
a forty-foot octagonal tower of unmortared stone. A
bottle-shaped hole runs its vertical length. Once
that hole was lined with firebrick. In it was
stoked a terribly hot charcoal fire, sustained by
pressurized air piped in at the bottom while
batches of charcoal and iron ore were fed in from
the top.
A Roman-style archway leads in toward the center
from four of the eight sides. Each is large enough
to be a one-car garage. They connect to a hole
where the smelted iron can run out and spread into
small pits and solidify into lumps called pigs. The
daily output of this huge smelter was
two-and-a-half tons of pig iron. That took four
tons of ore and twenty tons of charcoal.
The raw pig iron sold for two cents a pound. Iron
that was cast in its final form in a mold cost five
cents a pound. In 1838 the company turned a typical
profit of eight thousand dollars.
Iron was found in central New Hampshire in 1805.
Soon after, a group of Massachusetts investors set
up this ironworks. Housed in a large wooden
building, it was once a major feature beside the
small river. It lasted until maybe 1860. (We aren't
exactly sure, since records are so scanty.) Two
factors led to its end. One was the dependence on
charcoal. As the area around it was deforested, the
advantage of coal over wood became clear. The other
factor was Henry Bessemer's efficient new
steel-making process, invented in 1855. After that,
America rapidly moved away from small cast-iron
works like this and began making steel on a large
scale.
Now you can buy maple syrup across the street or
visit an old museum of 19th-century farm life. The
owner of the ironworks is setting up a bed and
breakfast. The air is clear and quiet. It's a nice
place indeed. But look closely and you see the
riverbank is built up from old iron tailings.
William Blake wrote these disturbing lines about
the same time this smelter was put up.
And did the Countenance Divine
Shine forth upon our clouded hills?
And was Jerusalem builded here
Among these dark Satanic mills?
Well, I suppose it did look pretty Satanic once.
Now it just seems so impossibly out-of-place amidst
all the tangled forest vegetation.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)