If one were to construct an undamped mechanical system resonant at 6
seconds, such as a Lehman, inverted pendulum, rocking chair, ball rolling
in a very shallow bowl, etc., could you see it move with the naked eye when
excited with these microseisms?

If so, put it in a clear case to keep air currents off and this could make
a striking display for schools, the public, etc.

Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......


At 01:19 AM 9/16/1999 -0500, Sean-Thomas wrote:
>Microseisms from hurricane Floyd:
>
>This evening the 6-second microseisms  have peaked at about 
>6 microns peak-peak at St. Louis. This is about 15 x the 
>normal value. They should be readily seen on any seismograph
>with an operating period longer than 1 second.


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