ENVIRO CRAZE WATCH:"environment-enhanced fatigue cracking"?

I've long been fascinated with the idea that living organisms are not the only things that age. From time to time, I've collected ancient coins, and I learned that forged coins pose a serious problem for the collector, because some of the forgers (especially those in Eastern Europe) use state of the art equipment once belonging to the KGB and its various manifestations. But there's one thing that can't be forged:when coins age,the metal changes.It crystallizes in predictable ways, and experts can tell by microscopic examination whether or not a coin is in fact 2000 years old.Knowing that even tiny pieces of metal change simply because of aging,this morning I wondered about a heavily-used metal bridge built in Minneapolis in 1967, when standards were considerably more lax than they are today.Think about the number of cars that passed over that bridge for the past 40 years,the number of times it has been repaired and resurfaced with heavy equipment rattling away,the number of ferocious winters and scorching summers it's been through. I'd be fatigued. Who wouldn't be? Who can blame the poor bridge, which is, after all only as strong as the metal supports holding it together....
To read more go to:
http://www.classicalvalues.com/archives/2007/08/environmentenha.html
As in the days of Noah...