Today, I would a cabin of mud and wattles make. 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.
Years ago, I taught for a
season in Southwest England. We lived in an old
Anglo-Saxon town -- in a thatch and cob cottage.
It'd stood for 500 years. Thatch is the thick woven
straw that makes the roof. The walls are a mixture
of clay and straw called cob, or sometimes tabby.
The material varies, as well as the name. Cob, or
tabby, is a poor man's masonry. To make it, you mix
a structural material -- like straw, corn stubble,
or oyster shells -- with clay or earth. It makes a
solid building material. In one form, we daub mud
onto wattles. Wattles are twigs woven together.
Cob was probably invented by the Phoenicians. The
Carthaginians learned it from them. The Romans
learned to make cob from the Carthaginians. Later,
the Romans invented concrete. After that, we find
walls of concrete cob that still stand today. Cob
went from Rome to Spain, and into Europe and
England.
The written record of tabby and cob is confusing
because it has to be reinvented in every land. Mud,
clay, and all the filler materials occur in such
variety that the stuff defies identification. In
the early 1500s, building on Tenerife expanded
rapidly. Tabby was the best low-cost building
material. Records say that tabby workers who came
from Spain didn't know what they were doing. In
fact, it simply took a while to invent techniques
for using local materials.
So I go back to that wet winter in Devon, living in
a cob house. One night at supper, we heard a
chilling PLOP. We turned and saw a huge scar on the
wall. A square foot of clay had fallen out and
splashed over the floor. Cob, it seems, must be
patched regularly. And so it had been for 500 years
before we came.
Mud and filler composites are among the oldest and
most widely used materials on earth. We live in
boxes of concrete and glass -- wood, brick, and
steel. We forget the potential, even today, of odd
mixtures of materials. We forget mud and straw.
The poet, Yeats, dreamt
of going back to Inisfree -- to that tiny wild
island in a lake near Sligo, in Ireland. He dreamt
of creating a place to be, from mud and wattles. I
doubt he ever really tried the trick. Cob may be a
poor man's masonry, but it's not a poor craftsman's
enterprise.
Yeats is buried near Inisfree, where he dreamt
about shaping clay. When he passed back into earth,
he left this on his head stone: "Cast a cold Eye,
On Life on Death, Horseman pass by." We forget the
old walls of mud & wattles -- of tabby and cob.
Yet they are the spit and clay that've formed our
civilization.
I'm John Lienhard at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
Glick, T.F., Cob Walls revisited: The Diffusion
of Tabby Con- struction in the Western Mediterranean
World. Humana Civilitas: Sources and Studies Relating
to the Middle Ages and the Renaissance. Vol.
I. On Pre-Modern Technology and Science.
(B.S. Hall, D.C. West, eds.) Malibu: Undena
Publications, 1976.
(I am grateful to Pat Bozeman, Head of Special
Collections, UH Library, for drawing my attention
to source and making her uncatalogued copy of it
available to me.)
Yeats, W.B., The Collected Poems of W.B.
Yeats. Definitive edi- tion, with the
author's final revisions, New York: Macmillan Co.,
1956.
The complete text of the Yeats poem to which I
allude, but from which I do not quote, is:
THE LAKE ISLE OF INISFREE
I will arise and go now, and go to Inisfree,
And a small cabin build there, of clay and wattles
made:
Nine bean-rows will I have there, a hive for the
honeybee,
and live alone in the bee-loud glade.
And I shall have some peace there, for peace comes
dropping slow,
Dropping from the veils of the morning to where the
cricket sings;
There midnight's all a glimmer, and noon a purple
glow,
And evening full of the linnet's wings.
I will arise and go now, for always night and
day
I hear lake water lapping with low sounds by the
shore;
While I stand on the roadway, or on the pavements
grey,
I hear it in the deep heart's core.
William Butler Yeats
(Photo by John Lienhard)
Yeats' Isle of Inisfree
(Photo by John Lienhard)
Yeats' headstone in Sligo
The Engines of Our Ingenuity is
Copyright © 1988-1997 by John H.
Lienhard.
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