Gentleman detective He lives in Paris with his close friend, the anonymous narrator of the stories. Like the much later Lord Peter Wimsey (see below), Dupin is a bibliophile, and met his narrator friend while both were searching for "the same rare and very remarkable volume" in an obscure library. For hobbies, Dupin is "fond" of enigmas, conundrums, and hieroglyphics. Dupin also bears the French title "Chevalier", meaning that he is a knight in the Légion d'honneur. The classic British gentleman detective appears soon after Poe's Dupin. A gentleman amateur is the ultimate hero of "The Moonstone" (1868), a famous epistolary novel
Dupin cyclide Dupin cyclide In mathematics, a Dupin cyclide or cyclide of Dupin is any geometric inversion of a standard torus, cylinder or double cone. In particular, these latter are themselves examples of Dupin cyclides. They were discovered by (and named after) Charles Dupin in his 1803 dissertation under Gaspard Monge. The key property of a Dupin cyclide is that it is a channel surface (envelope of a one-parameter family of spheres) in two different ways. This property means that Dupin cyclides are natural objects in Lie sphere geometry. Dupin cyclides are often simply known as "cyclides", but the latter term is