quoted 3 lines Maybe you've heard that bridges can and have collapsed from vibrating at>Maybe you've heard that bridges can and have collapsed from vibrating at
>a certain frequency. (hence there are laws, i think, about not having
>marching bands play accross bridges!)
Why don't people read the alt.folklore.urban FAQ? Here's a selection from
it (T./F. = True/False, U. = Unknown, Fb. = Believed False):
T. Soldiers break step when marching over bridges (trivially observed).
U. Bridge falls down if soldiers don't break step when marching over.
Fb.Bridge falls down due to resonance if soldiers don't break step marching
over. Broughton suspension bridge, England, 14 April 1831, fell under
soldiers march, but prob just overloaded, not resonating. Mark Brader
F. Otherwise sound bridge falls down if soldiers don't break step marching
over. (There have been no documented instances of this)
C.
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cspot@hyperreal.com (Chris.Hilker) ...electro-spiritual in composition...