Detective fiction underworld and undercover surveillance, rather than brilliance of imagination or intellect. Detective fiction in the English-speaking world is considered to have begun in 1841 with the publication of Poe's "The Murders in the Rue Morgue", featuring "the first fictional detective, the eccentric and brilliant C. Auguste Dupin". When the character first appeared, the word detective did not even exist. However, the character's name, "Dupin", originated from the English word dupe or deception. Poe devised a "plot formula that's been successful ever since, give or take a few shifting variables." Poe followed with further Auguste Dupin tales: "The Mystery of Marie
Dupin cyclide "R" are a 3-dimensional vectors, and "A" and "B" are constants. Families of cyclides give rise to various cyclidic coordinate geometries. In Maxime Bôcher's 1891 dissertation, "Ueber die Reihenentwickelungen der Potentialtheorie", it was shown that the Laplace equation in three variables can be solved using separation of variables in 17 conformally distinct quadric and cyclidic coordinate geometries. Many other cyclidic geometries can be obtained by studying R-separation of variables for the Laplace equation. 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