Villarceau Circles
Another special case is the Villarceau circles, in which the intersection is a circle despite the lack of any of the obvious sorts of symmetry that would entail a circular cross-section.
Read more about this topic: Toric Section
Famous quotes containing the word circles:
“The whole force of the respectable circles to which I belonged, that respectable circle which knew as I did not the value of security won, the slender chance of replacing it if lost or abandoned, was against me ...”
—Ida M. Tarbell (1857–1944)