Today, we learn about something called a square set.
The University of Houston's College of Engineering
presents this series about the machines that make our
civilization run, and the people whose ingenuity
I have here a copy of
Agricola's 16th-century treatise on metallurgy,
De Re Metallica. Book V tells us how to
do underground mining, and it's pretty complete. When
you dig for ore you have to shore up the tunnels so
they won't cave in. Agricola describes the
well-developed techniques of 1550 for setting support
timbers in mines.
Three hundred years later, in 1859, silver was
discovered in Virginia City,
Nevada. Those veins were called the Comstock
Lode. It was a remarkable find; but after a year of
chasing huge veins into the hillside, the miners had
opened caverns that could no longer be shored up by
the techniques of 1550. The mines caved in with such
regularity that miners were quitting.
Finally, the trustees of one mine heard about a very
bright German mining engineer in California. His name
was Philipp Deidesheimer, and he was only 28.
Deidesheimer came to Virginia City, and after several
weeks he was no closer to a solution than anyone
else. The mines kept caving in around the pine
columns used to shore up the brittle quartz
One night at a party, Deidesheimer's host -- a
bee-keeper -- showed him his bee-hives. Deidesheimer
suddenly saw those hives with a new set of eyes.
Their cellular structure was remarkably strong and
light. Why not? he thought. Why not! He rushed from
the party to his office. Three days later he took a
completely new sort of structure down into the mines.
Do you remember building with Lincoln Logs when you
were a kid? Well, that's how he made the bracing. He
used a timber frame of interlocking cubical elements,
4 to 6 feet on a side. The excavation itself could
wander wherever it wanted to. Deidesheimer simply
filled it up with a beehive that was cubical instead
of hexagonal. He called it the square set.
Deidesheimer didn't think to patent the square set.
If he had, it would have made him rich, because the
square set was the first real leap forward in shoring
up excavations since Agricola. Today, it's the only
structure detailed in my Britannica
article on mining.
Deidesheimer did become wealthy. He went off into
various speculations and got rich several times. But
he lost his shirt just as often, and in 1906 he died
That brilliant insight in the summer of 1860 might've
been a one-time flash in the pan, but I don't think
so. When you know how to search your mind, ideas do
come. It's too bad Deidesheimer didn't stay in
engineering. That's where a person who can look at a
beehive and change the world -- should be.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
Sagan, R., One Night of Brilliant Work. American
Heritage of Invention and Technology, Summer
1987, p. 64.
Agricola, G., De Re Metallica (H.C. and
L.H. Hoover, eds.). New York: Dover Publications
This episode has been greatly revised as Episode 1901.
Typical timber square set bracing as illustrated in a
19th century magazine
The Engines of Our Ingenuity is
Copyright © 1988-1997 by John H.