ABSTRACT
In a sequel to Flatland, an octagon by the name of Mr. Puncto surveys some rather large triangles and finds that each has angles that add up to slightly more than 180°! This discovery excites Mr. Puncto, and, after double checking his data, he makes the discovery pub lic. Unfortunately neither the civil authorities nor the scientific establishment shares his excitement. They suspect he is merely inventing excuses to explain some errors in his measurements, and they dismiss him from his job. The true explanation is that the Flatlanders are living not in a plane but on a sphere,
and on a sphere the angles of a triangle really do add up to more than 180°, as we shall soon see. This in cident and much more is described in the book Sphereland by Dionys Burger. I heartily recommend Sphereland to all readers of the present book (just don’t be put off by the rather dull summary of Flatland at the beginning).
