Trefoil Knot in Paper forms Pentagon/Historical Note

Historical Note on Trefoil Knot in Paper forms Pentagon

This construction first occurred in Urbano d'Aviso's Trattato della Sfera, 2nd ed. of $1682$.

It appears to have been added as an afterthought, as the rest of the work does not depend upon the construction of polygons.

This construction regularly crops up in puzzle anthologies.

Sources

• 1992: David Wells: Curious and Interesting Puzzles ... (previous) ... (next): Henry van Etten: $126$