The trammell of Archimedes is a clever device the great thinker designed to draw ellipses. (Does it?) Cf. http://en.wikipedia.org/wiki/Trammel_of_Archimedes
This is a trammell that is adjustable. What shapes can it make?
In Archimedes' device the shape has a constant distance between the two points that hold the rod. What parameters does that effect and how?
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