Francis Guthrie

Events

1

Episodes

2

Years

1852

Every event in Historedia whose sources name Francis Guthrie, with the role they cite and all of that event’s episodes. This is not a biography, and mentions are grouped by name, so two people with the same name can share this page.

Events and episodes

1. Francis Guthrie conjectures the four color theorem at University College London

   1852

   Role: Conjecturer

   1. 11852 · unspecifiedCommunication to De Morgan

      Guthrie inquired with his brother Frederick, who then took the question to Augustus De Morgan.

   2. 223 October 1852 · unspecifiedObservation of Four Colors

      Francis Guthrie noticed that only four colors were needed to color the map of counties of England, leading to the conjecture.

Sources

1. Francis Guthrie Wikipedia, revision of 2026-08-04
2. Four color theorem Wikipedia, revision of 2026-09-20