C. Auguste Dupin Dostoevsky called Poe "an enormously talented writer" and favorably reviewed Poe's detective stories. The character Porfiry Petrovich in Dostoevsky's novel "Crime and Punishment" was influenced by Dupin. In the first Sherlock Holmes story, "A Study in Scarlet" (1887), Doctor Watson compares Holmes to Dupin, to which Holmes replies: "No doubt you think you are complimenting me ... In my opinion, Dupin was a very inferior fellow... He had some analytical genius, no doubt; but he was by no means such a phenomenon as Poe appears to imagine". Alluding to an episode in "The Murders in the Rue Morgue", where Dupin
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