Writing | |

On the divided line from ’s Republic A proof that the middle segments are always equal, in the style of Euclid. | |

’s proof of a minimum property of the orthic triangle A visual proof, intended for non-mathematicians. | |

Errata for ’s Symmetry A guide for Weyl’s magnificent book. | |

Translation | |

Review of
– ’s Géométrie descriptive A magisterial discussion of geometry. | |

On the analog of crystallographic symmetry in the plane
– Pólya’s lively 1924 article on the classification of wallpaper groups. | |

World record surfaces: algebraic surfaces with many singularities
– A semi-popular expository article with very many pictures. |