Jim Sharkey schreef:
> It might seem a little trivial, but what about concrete? Without it, for
> better or worse, we wouldn't be the kinds of cities and infrastructures that
> we do. Without those, who knows what general economic system would have
> been adopted by most of the world?
>
> Oddly enough, IIRC, the inventor of concrete figured it would last about ten
> years. Turned out he was off by a factor of ten.
As far as I know concrete is another one of those nice re-inventions. I think
the Romans already used it in their constructions. The formula to make it was
forgotten and then reinvented again. What can be considered a new invention is
the reinforced concrete. Which allowes us to span distances just using the
concrete structure.
Sonja
