>> (Do you know what it is yet?  If you know your history of
 >> physics that should be hint enough.  ;-)

 MvV>> Ah, yes of course. Get a rope and lower the barometer to the street
 MvV>> from  above as in one of the previous solutions. But instead of
 MvV>> measuring the length of the rope, bring it into swing and
 MvV>> measure the frequency.

 > I thought the tick-tocks should have reminded one of a
 > pendulum.

Yes, it did.

 > Further down, after many blank lines to hide it, I suggested
 > using piano wire for tensile strength.

He, I didn't see that! You hid it too well. My message reader always
displays blank lines at the end of the message, so I didn't look any
further, I assumed there was no more...

 > I thought a small cross section would help with both air
 > resistance and wind induced harmonic vibrations.

Most of the solutions given so far will have accuracy problems. They work
in principle but I think an accuracy analyses will reveal that in practice
they are quit useless including the "standard" solution of using
the device as a barometric altimeter. 1 meter corresponds to less than a
tenth of mm on the barometer.

Regarding accuracy the method with the rope is the best.

Cheers, Michiel

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