The trisection that Viete gives in " A Supplement to goemetry"
Prop. IX is almost identical to the one that Archimedes gives in his
book of lemmata, and I have seen the same construction also referred
to the mathematical collection of Pappus, though I did not verify the
reference myself.
So my question is, is it possible that Viete was unaware of these
sources and thought that he had discovered this construction himself?
Otherwise why whould he be so proud of it?
By the way, I suppose the construction of the heptagon is original
to Viete, and that he has sufficient reason to be proud of that one.
Greetings from Berkeley
Robin Hartshorne