Lake Michigan

The Möbius strip, a non-orientable two-dimensional surface with only one side when embedded in three-dimensional Euclidean space.  The Möbius configuration, formed by two mutually inscribed tetrahedra, is also named after Möbius. August Ferdinand Möbius was the first to introduce homogeneous coordinates into projective geometry. He is recognized for the introduction of the Barycentric coordinate system. Before 1853 and Schläfli’s discovery of the 4-polytopes, Mobius (with Cayley and Grassmann) was one of only three other people who had also conceived of the possibility of geometry in more than three dimensions.