When circles don't look like circles: An optical theorem in Euclid and Pappus (Q1205984)

The author discusses Euclid's erroneous treatment of prop. 37 in the Optics (that the wheels of chariots sometimes will appear circular, sometimes pressed in). This treatment gave rise to a series of errors with Pappus in his commentary on the Optics in Book VI of the Collection (ed. Hultsch, II, 568. 13-594.26). In section I the author summarizes the propositions given by both geometers, in section II he summarizes the erroneous features of the proofs, and in section III he provides proofs of the corrected propositions. In section IV he discusses the Euclidean perspective system, and, finally, in an appendix he gives additional proofs (via modern methods).