On Sun, 12 Aug 2007 21:33:00 -0500, "David R. Birch"
wrote:

So you're saying that 2000 years ago, they built bridges that can take
the stress of many 18 wheel semi trailer trucks daily without regular
inspection and maintenance, and that there have been NO failures of
any of these bridges?

In the main yes. There are no elements in tension and the stone and
bedrock they are built on have huge resistance to compressive failure.

The choice is build cheap, fast, or properly. Choose one. Some
places still have iron bridges that have been standing for over 200
years.


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