On Tue, 1 Feb 2000, Andrew Brown wrote:

> right.  i didn't mean that things that were reflectively symmetric
> were not okay, but just that that wasn't the operating principle.

I would think that rotational symmetry is not necessary at all. What I
guess would be necessary for stable operation is that, given a line at
any angle passing through the centre of the disc, the centrifugal force
exerted by the masses on either side of that line would be equal.

cjs
-- 
Curt Sampson  <cjs@cynic.net>   917 532 4208   De gustibus, aut bene aut nihil.
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