Tangential by Helen HiebertAfter viewing (and handling) the 1570 edition of Euclids Elements of Geometry at the Denver Public Library, Hiebert was drawn to Chapter 11, which focuses on polyhedra. Hiebert finds it interesting to imagine how Euclid constructed his ideas in the physical world, since paper was invented later. Perhaps he constructed them in papyrus or parchment (precursors to paper). Hiebert is intrigued by the many ways in which a flat sheet of paper can transform