The Murders in the Rue Morgue C. Auguste Dupin and the Paris setting. Dupin reappeared in "The Purloined Letter", which Poe called "perhaps the best of my tales of ratiocination" in a letter to James Russell Lowell in July 1844. The original manuscript of "The Murders in the Rue Morgue" which was used for its first printing in "Graham's Magazine" was discarded in a wastebasket. An apprentice at the office, J. M. Johnston, retrieved it and left it with his father for safekeeping. It was left in a music book, where it survived three house fires before being bought by George William Childs. In 1891, Childs
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